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Find video protocols related to scientific articles indexed in Pubmed.
[A population-based epidemiological survey of neonatal respiratory failure in Huai'an City of Jiangsu Province, in 2010.]
Zhongguo Dang Dai Er Ke Za Zhi
PUBLISHED: 11-20-2014
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To investigate the prevalence, clinical characteristics, treatment, and prognosis of neonatal respiratory failure (NRF) in Huai'an, Jiangsu Province, China, in 2010.
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Defects in a new class of sulfate/anion transporter link sulfur acclimation responses to intracellular glutathione levels and cell cycle control.
Plant Physiol.
PUBLISHED: 11-02-2014
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We previously identified a mutation, smt15-1, that partially suppresses the cell cycle defects caused by loss of the retinoblastoma tumor suppressor related protein (RBR) encoded by the MAT3 gene in Chlamydomonas reinhardtii. smt15-1 single mutants were also found to have a cell cycle defect leading to a small-cell phenotype. SMT15 belongs to a previously uncharacterized sub-family of putative membrane localized sulfate/anion transporters that contain a Sulfate_transp domain and are found in a widely distributed subset of eukaryotes and bacteria. Although we observed that smt15-1 has a defect in acclimation to sulfur-limited growth conditions, sac mutants that are more severely defective for acclimation to sulfur limitation do not have cell cycle defects and cannot suppress mat3. Moreover, we found that smt15-1, but not sac mutants, over-accumulates glutathione. In wild-type cells glutathione fluctuated during the cell cycle with highest levels in mid-G1 phase and lower levels during S and M phases, while in smt15-1 glutathione levels remained elevated during S and M. In addition to increased total glutathione levels, smt15-1 cells had increased GSH/GSSH redox ratio throughout the cell cycle. These data suggest a role for SMT15 in maintaining glutathione homeostasis that impacts the cell cycle and sulfur acclimation responses.
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Statistical strategies for microRNAseq batch effect reduction.
Transl Cancer Res
PUBLISHED: 09-27-2014
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RNAseq technology is replacing microarray technology as the tool of choice for gene expression profiling. While providing much richer data than microarray, analysis of RNAseq data has been much more challenging. Among the many difficulties of RNAseq analysis, correctly adjusting for batch effect is a pivotal one for large-scale RNAseq based studies. The batch effect of RNAseq data is most obvious in microRNA (miRNA) sequencing studies. Using real miRNA sequencing (miRNAseq) data, we evaluated several batch removal techniques and discussed their effectiveness. We illustrate that by adjusting for batch effect, more reliable differentially expressed genes can be identified. Our study on batch effect in miRNAseq data can serve as a guideline for future miRNAseq studies that might contain batch effect.
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A 10-year experience with hepatic trauma in a Chinese level one trauma center.
Saudi Med J
PUBLISHED: 09-18-2014
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To analyze strategies of operative management (OM) and non-operative management (NOM), mortality, and morbidity of hepatic trauma patients.
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Variants in Complement Factor H and Complement Factor H-Related Protein Genes, CFHR3 and CFHR1, Affect Complement Activation in IgA Nephropathy.
J. Am. Soc. Nephrol.
PUBLISHED: 09-11-2014
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Complement activation is common in patients with IgA nephropathy (IgAN) and associated with disease severity. Our recent genome-wide association study of IgAN identified susceptibility loci on 1q23 containing the complement regulatory protein-encoding genes CFH and CFHR1-5, with rs6677604 in CFH as the top single-nucleotide polymorphism and CFHR3-1 deletion (CFHR3-1?) as the top signal for copy number variation. In this study, to explore the clinical effects of variation in CFH, CFHR3, and CFHR1 on IgAN susceptibility and progression, we enrolled two populations. Group 1 included 1178 subjects with IgAN and available genome-wide association study data. Group 2 included 365 subjects with IgAN and available clinical follow-up data. In group 1, rs6677604 was associated with mesangial C3 deposition by genotype-phenotype correlation analysis. In group 2, we detected a linkage between the rs6677604-A allele and CFHR3-1? and found that the rs6677604-A allele was associated with higher serum levels of CFH and lower levels of the complement activation split product C3a. Furthermore, CFH levels were positively associated with circulating C3 levels and negatively associated with mesangial C3 deposition. Moreover, serum levels of the pathogenic galactose-deficient glycoform of IgA1 were also associated with the degree of mesangial C3 deposition in patients with IgAN. Our findings suggest that genetic variants in CFH, CFHR3, and CFHR1 affect complement activation and thereby, predispose patients to develop IgAN.
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Unusual high oxygen reduction performance in all-carbon electrocatalysts.
Sci Rep
PUBLISHED: 09-05-2014
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Carbon-based electrocatalysts are more durable and cost-effective than noble materials for the oxygen reduction reaction (ORR), which is an important process in energy conversion technologies. Heteroatoms are considered responsible for the excellent ORR performance in many carbon-based electrocatalysts. But whether an all-carbon electrocatalyst can effectively reduce oxygen is unknown. We subtly engineered the interfaces between planar graphene sheets and curved carbon nanotubes (G-CNT) and gained a remarkable activity/selectivity for ORR (larger current, and n = 3.86, ~93% hydroxide + ~7% peroxide). This performance is close to that of Pt; and the durability is much better than Pt. We further demonstrate the application of this G-CNT hybrid as an all-carbon cathode catalyst for lithium oxygen batteries.We speculate that the high ORR activity of this G-CNT hybrid stems from the localized charge separation at the interface of the graphene and carbon nanotube, which results from the tunneling electron transfer due to the Fermi level mismatch on the planar and curved sp(2) surfaces. Our result represents a conceptual breakthrough and pioneers the new avenues towards practical all-carbon electrocatalysis.
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Plasmonic nanoparticle-film calipers for rapid and ultrasensitive dimensional and refractometric detection.
Analyst
PUBLISHED: 08-14-2014
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In this study, we develop an ultrasensitive nanoparticle (NP)-film caliper that functions with high resolution (angstrom scale) in response to both the dimensions and refractive index of the spacer sandwiched between the NPs and the film. The anisotropy of the plasmonic gap mode in the NP-film caliper can be characterized readily using spectroscopic ellipsometry (SE) without the need for further optical modeling. To the best of our knowledge, this paper is the first to report the use of SE to study the plasmonic gap modes in NP-film calipers and to demonstrate that SE is a robust and convenient method for analyzing NP-film calipers. The high sensitivity of this system originates from the plasmonic gap mode in the NP-film caliper, induced by electromagnetic coupling between the NPs and the film. The refractometric sensitivity of this NP-film caliper reaches up to 314 nm per RIU, which is superior to those of other NP-based sensors. The NP-film caliper also provides high dimensional resolution, down to the angstrom scale. In this study, the shift in wavelength in response to the change in gap spacing is approximately 9 nm Å(-1). Taking advantage of the ultrasensitivity of this NP-film caliper, we develop a platform for discriminating among thiol-containing amino acids.
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Continuous dopaminergic stimulation (CDS)-based treatment in Parkinson's disease patients with motor complications: a systematic review and meta-analysis.
Sci Rep
PUBLISHED: 08-12-2014
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A systematic review of the literature was conducted to identify randomized trials involving continuous dopaminergic stimulation (CDS) in PD patients with motor complications. Difference between n groups was assessed by partitioning heterogeneity and using the ?2 distribution with n-1 degrees of freedom, where n equals the number of groups. We looked for publication bias using funnel plotting, Egger's test and Begg's test. Twenty Randomized Controlled Trials (RCTs) were included. The results showed that CDS could evidently improve the Unified Parkinson's Disease Rating Scale (UPDRS) Part II (p < 0.0001), part III (P < 0.00001) and UPDRS total score (p < 0.00001). There was also a statistical discrepancy in off time reduction (p < 0.00001) and prolongation of on time (p < 0.00001) by the CDS therapy compared with control groups. Meanwhile, the results of this study showed obvious side effects in the CDS therapy compared with the placebo, especially at the expense of increased dyskinesia (23.4% vs 11.7%). The present study showed that CDS was beneficial in the treatment of PD patients with motor complications. But the incidence of the side events is more common than placebo.
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Lipid-Lowering Effects of Curcumin in Patients with Metabolic Syndrome: A Randomized, Double-Blind, Placebo-Controlled Trial.
Phytother Res
PUBLISHED: 08-06-2014
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Human studies of curcumin extract on lipid-lowering effect have not been completely investigated and have had controversy results. This study tested the effect of daily curcumin extract for 12?weeks on weight, glucose, and lipid profiles in patients with metabolic syndrome. Sixty-five patients were randomized into two groups; 33 patients taking curcumin extract capsule (630?mg thrice daily) and 32 patients taking a placebo capsule thrice daily for 12?weeks. At 12?weeks after the curcumin extract consumption, the level of high-density lipoprotein cholesterol (HDL-C) significantly increased from 40.96?±?8.59 to 43.76?±?2.79?mg/dL (p?
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Gender difference in the association of hyperuricemia with hypertension in a middle-aged Chinese population.
Blood Press.
PUBLISHED: 06-06-2014
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Abstract In this study, we report the relationship between hyperuricemia and hypertension in a middle-aged Chinese population, emphasizing the difference of gender. The cross-sectional study was conducted among 1776 adults aged 45-60 years, who participated in the Hefei Nutrition and Health Study (2012). Hyperuricemia was defined as serum uric acid (SUA)> 420 ?mol/l for men, and > 360 ?mol/l for women. Hypertension was defined as systolic blood pressure (SBP) ? 140 mmHg or diastolic blood pressure (DBP) ? 90 mmHg. Anthropometric measurements and biochemical data were collected using standardized procedures. Multivariate logistic regression analysis was performed to determine the relationship between hyperuricemia and hypertension with adjustment of potential confounding factors. Body mass index (BMI), waist circumference (WC), SBP, DBP, fasting glucose, SUA and the prevalence of hyperuricemia and hypertension were significantly higher in male than in female (p < 0.001). Females had significantly higher levels of triglycerides (TG) and high-density lipoprotein (HDL)-cholesterol (5.23 ± 0.87 vs 5.12 ± 1.01, p < 0.05, 1.50 ± 0.37 vs 1.28 ± 0.41, respectively.) than males. Simple correlation analysis showed that SUA was positively associated with WC and TG. In addition, after adjusting for potential confounders, hyperuricemia was associated with increased risk of hypertension in both males and females, with odds ratios (95% CI) of 1.680 (1.110-2.543) and 1.065 (1.012-1.118), respectively.
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D-amino acids inhibit initial bacterial adhesion: Thermodynamic evidence.
Biotechnol. Bioeng.
PUBLISHED: 05-25-2014
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Bacterial biofilms are structured communities of cells enclosed in a self-produced hydrated polymeric matrix that can adhere to inert or living surfaces. D-amino acids were previously identified as self-produced compounds that mediate biofilm disassembly by causing the release of the protein component of the polymeric matrix. However, whether exogenous D-amino acids could inhibit initial bacterial adhesion is still unknown. Here, the effect of the exogenous amino acid D-tyrosine on initial bacterial adhesion was determined by combined use of chemical analysis, force spectroscopic measurement, and theoretical predictions. The surface thermodynamic theory demonstrated that the total interaction energy increased with more D-tyrosine, and the contribution of Lewis acid-base interactions relative to the change in the total interaction energy was much greater than the overall nonspecific interactions. Finally, atomic force microscopy (AFM) analysis implied that the hydrogen bond numbers and adhesion forces decreased with the increase in D-tyrosine concentrations. D-tyrosine contributed to the repulsive nature of the cell and ultimately led to the inhibition of bacterial adhesion. This study provides a new way to regulate biofilm formation by manipulating the contents of D-amino acids in natural or engineered systems. Biotechnol. Bioeng. © 2014 Wiley Periodicals, Inc.
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Using multiplexed assays of oncogenic drivers in lung cancers to select targeted drugs.
JAMA
PUBLISHED: 05-22-2014
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Targeting oncogenic drivers (genomic alterations critical to cancer development and maintenance) has transformed the care of patients with lung adenocarcinomas. The Lung Cancer Mutation Consortium was formed to perform multiplexed assays testing adenocarcinomas of the lung for drivers in 10 genes to enable clinicians to select targeted treatments and enroll patients into clinical trials.
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Development and preliminary testing of an instrument to measure healthiness of lifestyle among breast cancer survivors.
Int J Nurs Pract
PUBLISHED: 05-21-2014
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Monitoring lifestyle to maintain health is an important issue for breast cancer survivors. No multidimensional instrument has previously been available specifically for assessing overall healthiness of lifestyle among breast cancer survivors. This study aims (i) to establish the Healthy Lifestyle Instrument for Breast Cancer Survivors (HLI-BCS) and (ii) to examine the reliability and validity of the established scale. A quantitative cross-sectional design was used. This project was conducted in four phases. In phase I, using the Health-Promoting Lifestyle Profile as the core concept, we created 50 preliminary measurement items. In phase II, we invited 10 breast cancer survivors and five professional experts to conduct a content validity assessment. In phases III and IV, a total of 220 breast cancer survivors were enrolled to assess the construct validity and the internal consistency and reliability. The final HLI-BCS contains 20 items across five domains: dietary habits, environment and physiology, health responsibility and stress management, social and interpersonal relations and spiritual growth. Through the information presented in the HLI-BCS, breast cancer survivors can assess their lifestyles on multiple dimensions and subsequently adjust their lifestyles to enhance their recovery and quality of life.
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Quantitative Imaging of Preamyloid Oligomers, a Novel Structural Abnormality, in Human Atrial Samples.
J. Histochem. Cytochem.
PUBLISHED: 04-30-2014
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Abnormalities in atrial myocardium increase the likelihood of arrhythmias, including atrial fibrillation (AF). The deposition of misfolded protein, or amyloidosis, plays an important role in the pathophysiology of many diseases, including human cardiomyopathies. We have shown that genes implicated in amyloidosis are activated in a cellular model of AF, with the development of preamyloid oligomers (PAOs). PAOs are intermediates in the formation of amyloid fibrils, and they are now recognized to be the cytotoxic species during amyloidosis. To investigate the presence of PAOs in human atrium, we developed a microscopic imaging-based protocol to enable robust and reproducible quantitative analysis of PAO burden in atrial samples harvested at the time of elective cardiac surgery. Using PAO- and myocardial-specific antibodies, we found that PAO distribution was typically heterogeneous within a myocardial sample. Rigorous imaging and analysis protocols were developed to quantify the relative area of myocardium containing PAOs, termed the Green/Red ratio (G/R), for a given sample. Using these methods, reproducible G/R values were obtained when different sections of a sample were independently processed, imaged, and analyzed by different investigators. This robust technique will enable studies to investigate the role of this novel structural abnormality in the pathophysiology of and arrhythmia generation in human atrial tissue.
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[The influence of sublingual immunotherapy on Th2 type immunoreaction in patients with allergic rhinitis].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 04-18-2014
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To explore the influence of sublingual immunotherapy on Th2 type immunoreaction in patients with allergic rhinitis within 12 months' treatment.
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Dietary patterns are associated with body mass index and bone mineral density in Chinese freshmen.
J Am Coll Nutr
PUBLISHED: 04-15-2014
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Our objective was to examine associations between dietary patterns and body mass index (BMI) and bone mineral density (BMD) in Chinese freshmen.
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Cumulative effects of variants identified by genome-wide association studies in IgA nephropathy.
Sci Rep
PUBLISHED: 04-11-2014
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The effect of genetic markers associated with IgA nephropathy on risk of disease in sub-phenotype and progression is uncertain. Data from 2096 Chinese patients were used to create both un-weighted (uw) and weighted (w) genetic risk score (GRS). The association between GRS with disease susceptibility and clinical parameters were assessed. All nine selected single nucleotide polymorphisms (SNPs) were associated with susceptibility to IgAN. uwGRS and wGRS showed a similar fit in disease associations. With every 1-unit increase in the uwGRS, the disease risk increased by approximately 20%; whereas every one standard deviation increase in the wGRS, disease risk increased by approximately 40% ~ 60%. Association between rs3803800 and serum IgA was replicated, and risk groups in GRSs were associated with increased IgA/IgA1 levels. uwGRS9 ? 16 was an independent predictor for end stage renal disease (ESRD) in IgAN, with a relative risk of 2.52 (p = 6.68 × 10(-3)). In conclusion, we observed that GRSs comprising nine SNPs identified in a GWAS of IgAN were strongly associated with susceptibility to IgAN. The high risk GRS9 group had a high risk of ESRD in follow-up.
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The association between the LRRK2 G2385R variant and the risk of Parkinson's disease: a meta-analysis based on 23 case-control studies.
Neurol. Sci.
PUBLISHED: 04-07-2014
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Clinical diagnosis of Parkinson's disease (PD) is essential but misdiagnosis of PD-like diseases is quite common. LRRK2 G2385R variants have been extensively examined for the association to the risk of Parkinson's disease. However, results from different studies are inconsistent. The purpose of this meta-analysis was to assess the association between the LRRK2 G2385R variants and the risk of PD. A systematic literature search was performed for 6 databases up to January of 2014 to identify case-control studies involving LRRK2 G2385R variants and the risk of PD. A total of 12,915 cases and 12,451 controls in 23 case-control studies were included in this meta-analysis. The results indicated that the variant A allele carriers (GA + AA) increased risk of PD when compared with the homozygote GG (GA + AA vs. GG: OR = 2.4, 95 % CI = 1.97 to 2.92, P < 0.00001). In the subgroup analysis by ethnicity, increased risks were identified among Chinese (OR = 2.69, 95 % CI = 2.1-3.45, P < 0.00001) as well as in non-Chinese (OR = 2.17, 95 % CI 1.75-2.69, P < 0.00001). In the subgroup analysis by age of onset, significant associations were found in both later-onset PD (LOPD) and early-onset PD (EOPD) cases. And there was no significant difference of the allele frequency between patients with LOPD and EOPD (OR = 1.18, 95 % CI = 0.77-1.80, P = 0.45). Our results suggest that the LRRK2 G2385R variants contribute to the susceptibility of PD especially in Chinese PD. Meanwhile, it is possible that age is not the risk factor to facilitate G2385R gene mutation.
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A putative novel protein, DEPDC1B, is overexpressed in oral cancer patients, and enhanced anchorage-independent growth in oral cancer cells that is mediated by Rac1 and ERK.
J. Biomed. Sci.
PUBLISHED: 03-26-2014
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The DEP domain is a globular domain containing approximately 90 amino acids, which was first discovered in 3 proteins: Drosophila disheveled, Caenorhabditis elegans EGL-10, and mammalian Pleckstrin; hence the term, DEP. DEPDC1B is categorized as a potential Rho GTPase-activating protein. The function of the DEP domain in signal transduction pathways is not fully understood. The DEPDC1B protein exhibits the characteristic features of a signaling protein, and contains 2 conserved domains (DEP and RhoGAP) that are involved in Rho GTPase signaling. Small GTPases, such as Rac, CDC42, and Rho, regulate a multitude of cell events, including cell motility, growth, differentiation, cytoskeletal reorganization and cell cycle progression.
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Involvement of TG-interacting factor in microglial activation during experimental traumatic brain injury.
J. Neurochem.
PUBLISHED: 03-10-2014
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Traumatic brain injury (TBI) is a complex injury involving several physiological alterations, potentially leading to neurological impairment. Previous mouse studies using high-density oligonucleotide array analysis have confirmed the upregulation of transforming growth-interacting factor (TGIF) mRNA in TBI. TGIF is a transcriptional corepressor of transforming growth factor beta (TGF-?) signaling which plays a protective role in TBI. However, the functional roles of TGIF in TBI are not well understood. In this study, we used confocal microscopy after immunofluorescence staining to demonstrate the increase of TGIF levels in the activated microglia of the pericontusional cortex of rats with TBI. Intracerebral knockdown of TGIF in the pericontusional cortex significantly downregulated TGIF expression, attenuated microglial activation, reduced the volume of damaged brain tissue, and facilitated recovery of limb motor function. Collectively, our results indicate that TGIF is involved in TBI-induced microglial activation, resulting in secondary brain injury and motor dysfunction. This study investigated the roles of transforming growth-interacting factor (TGIF) in a traumatic brain injury (TBI)-rat model. We demonstrated the increase of TGIF levels in the activated microglia of the pericontusional cortex of rats with TBI. Intracerebral knockdown of TGIF in the pericontusional cortex of the TBI rats significantly attenuated micoglial activation, reduced the volume of damaged brain tissue, and facilitated recovery of limb motor function. We suggest that inhibition of TGIF might provide a promising therapeutic strategy for TBI.
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Sample size determination for paired right-censored data based on the difference of Kaplan-Meier estimates.
Comput Stat Data Anal
PUBLISHED: 02-26-2014
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Sample size determination is essential to planning clinical trials. Jung (2008) established a sample size calculation formula for paired right-censored data based on the logrank test, which has been well-studied for comparing independent survival outcomes. An alternative to rank-based methods for independent right-censored data, advocated by Pepe and Fleming (1989), tests for differences between integrated weighted Kaplan-Meier estimates and is more sensitive to the magnitude of difference in survival times between groups. In this paper, we employ the concept of the Pepe-Fleming method to determine an adequate sample size by calculating differences between Kaplan-Meier estimators considering pair-wise correlation. We specify a positive stable frailty model for the joint distribution of paired survival times. We evaluate the performance of the proposed method by simulation studies and investigate the impacts of the accrual times, follow-up times, loss to follow-up rate, and sensitivity of power under misspecification of the model. The results show that ignoring the pair-wise correlation results in overestimating the required sample size. Furthermore, the proposed method is applied to two real-world studies, and the R code for sample size calculation is made available to users.
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Effects of Kaixin Jieyu Decoction () on behavior, monoamine neurotransmitter levels, and serotonin receptor subtype expression in the brain of a rat depression model.
Chin J Integr Med
PUBLISHED: 02-24-2014
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To determine the mechanisms underlying the anti-depressant effects of Kaixin Jieyu Decoction (, KJD) by investigating the effects of KJD on behavior, monoamine neurotransmitter levels, and serotonin (5-HT) receptor subtype expression in the brain in a rat model of depression.
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The UPF1 RNA surveillance gene is commonly mutated in pancreatic adenosquamous carcinoma.
Nat. Med.
PUBLISHED: 02-21-2014
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Pancreatic adenosquamous carcinoma (ASC) is an enigmatic and aggressive tumor that has a worse prognosis and higher metastatic potential than its adenocarcinoma counterpart. Here we report that ASC tumors frequently harbor somatically acquired mutations in the UPF1 gene, which encodes the core component of the nonsense-mediated RNA decay (NMD) pathway. These tumor-specific mutations alter UPF1 RNA splicing and perturb NMD, leading to upregulated levels of NMD substrate mRNAs. UPF1 mutations are, to our knowledge, the first known unique molecular signatures of pancreatic ASC.
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Epstein-Barr virus BALF3 has nuclease activity and mediates mature virion production during the lytic cycle.
J. Virol.
PUBLISHED: 02-19-2014
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Epstein-Barr virus (EBV) lytic replication involves complex processes, including DNA synthesis, DNA cleavage and packaging, and virion egress. These processes require many different lytic gene products, but the mechanisms of their actions remain unclear, especially for DNA cleavage and packaging. According to sequence homology analysis, EBV BALF3, encoded by the third leftward open reading frame of the BamHI-A fragment in the viral genome, is a homologue of herpes simplex virus type 1 UL28. This gene product is believed to possess the properties of a terminase, such as nucleolytic activity on newly synthesized viral DNA and translocation of unit length viral genomes into procapsids. In order to characterize EBV BALF3, the protein was produced by and purified from recombinant baculoviruses and examined in an enzymatic reaction in vitro, which determined that EBV BALF3 acts as an endonuclease and its activity is modulated by Mg(2+), Mn(2+), and ATP. Moreover, in EBV-positive epithelial cells, BALF3 was expressed and transported from the cytoplasm into the nucleus following induction of the lytic cycle, and gene silencing of BALF3 caused a reduction of DNA packaging and virion release. Interestingly, suppression of BALF3 expression also decreased the efficiency of DNA synthesis. On the basis of these results, we suggest that EBV BALF3 is involved simultaneously in DNA synthesis and packaging and is required for the production of mature virions.
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[The development of psychiatric and mental health nursing in Taiwan].
Hu Li Za Zhi
PUBLISHED: 02-13-2014
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Psychiatric mental health is critical to ensuring the health and wellbeing of individuals, families, and communities. While psychiatric mental health work continues to become increasingly complex and challenging, the demand for psychiatric nurses with evidence-based skills continues to grow. Psychiatric mental health nurses (PMHNs) are the primary providers of professional psychiatric mental health care services. PMFNs emphasize humanistic values and focus on servicing patient and family needs. In Taiwan, the Psychiatric Mental Health Nursing Association constructs the competence-credentialing model for psychiatric mental health nursing that underpins the values, attitudes, and beliefs of PMHNs and ensures that the mental health nursing practice promotes public health and wellbeing. In addition, this association promotes advanced psychiatric nursing education, research, and practice, influences the national health agenda, and discusses and disseminates information on psychiatric mental health care issues in order to influence the direction, nature, and quality of psychiatric and mental health care.
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Osteogenesis and angiogenesis properties of dental pulp cell on novel injectable tricalcium phosphate cement by silica doped.
Mater Sci Eng C Mater Biol Appl
PUBLISHED: 02-05-2014
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?-Tricalcium phosphate (?-TCP) is an osteoconductive material in clinical. In this study, we have doped silica (Si) into ?-TCP and enhanced its bioactive and osteostimulative properties. To check its effectiveness, a series of Si-doped with different ratios were prepared to make new bioactive and biodegradable biocomposites for bone repair. Formation of the diametral tensile strength, ions released and weight loss of cements was considered after immersion. In addition, we also examined the behavior of human dental pulp cells (hDPCs) cultured on Si-doped ?-TCP cements. The results showed that setting time and injectability of the Si-doped ?-TCP cements were decreased as the Si content was increased. At the end of the immersion point, weight losses of 30.1%, 36.9%, 48.1%, and 55.3% were observed for the cement doping 0%, 10%, 20%, and 30% Si into ?-TCP cements, respectively. In vitro cell experiments show that the Si-rich cements promote human dental pulp cell (hDPC) proliferation and differentiation. However, when the Si-doped in the cement is more than 20%, the amount of cells and osteogenesis protein of hDPCs was stimulated by Si released from Si-doped ?-TCP cements. The degradation of ?-TCP and osteogenesis of Si gives a strong reason to believe that these Si-doped ?-TCP cements may prove to be promising bone repair materials.
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Birth weight and subsequent risk of asthma: a systematic review and meta-analysis.
Heart Lung Circ
PUBLISHED: 01-22-2014
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Previous studies suggest that birth weight is related to later risk of asthma. However, few meta-analyses have investigated these associations. Therefore, we performed a meta-analysis with different classifications to further validate the relationship between birth weight and asthma.
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Effect of nicotine on L-dopa-induced dyskinesia in animal models of Parkinson's disease: a systematic review and meta-analysis.
Neurol. Sci.
PUBLISHED: 01-22-2014
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L-dopa-induced dyskinesias (LIDs) are abnormal involuntary movements (AIM) that develop with long-term L-dopa therapy for Parkinson's disease (PD). In this study, we used these tools to describe the efficacy of nicotine reduced LID in animal models of PD. Studies were identified by electronic searching of six online databases up to September of 2013 to identify preclinical trials involving nicotine for LID in animal model. Data were extracted for AIM compared with LID animals. Pre-specified subgroup analysis was carried out according to method of model, gender, anesthetic used, and species. Combined standardized mean difference (SMD) estimates and 95 % confidence intervals (CIs) were calculated using a random-effects model. Eleven studies involving 181 animals which described the effect of nicotine on LID were included in the meta-analysis. Nicotine was efficacious in reducing total AIM compared with control group (SMD -3.77, 95 % CI -5.30 to -2.23, P < 0.00001). Meanwhile, four studies showed certain effects of nicotine for improving the axial AIM (SMD -2.21, 95 % CI -4.17 to -0.24, P = 0.03); oral AIM and forelimb AIM were obvious improved in six studies in the nicotine group (SMD -3.00, 95 % CI -4.55 to -1.44, P = 0.0002; SMD -2.52, 95 % CI -3.52 to -1.53, P < 0.00001, respectively). We conclude that nicotine appears to have efficacy in animal models of LID. Large randomized clinical trials testing the effect of nicotine in PD patients with LID are warranted.
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Liquid crystalline epoxy nanocomposite material for dental application.
J. Formos. Med. Assoc.
PUBLISHED: 01-20-2014
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Novel liquid crystalline epoxy nanocomposites, which exhibit reduced polymerization shrinkage and effectively bond to tooth structures, can be applied in esthetic dentistry, including core and post systems, direct and indirect restorations, and dental brackets. The purposes of this study were to investigate the properties of liquid crystalline epoxy nanocomposites including biocompatibility, microhardness, and frictional forces of bracket-like blocks with different filler contents for further clinical applications.
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Spontaneous spinal epidural hemorrhage from intense piano playing.
Am J Emerg Med
PUBLISHED: 01-15-2014
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Spontaneous spinal epidural hematoma (SSEH) is a rare but real neurosurgical emergency. It is caused by atraumatic rupture of the vertebral epidural vein that results in nerve root or spinal cord compression. Most cases of SSEH have a multifactorial etiology, including congenital and acquired coagulopathies; platelet dysfunction; vascular malformation; tumors; uncontrolled hypertension; pregnancy; and, very rarely, activities requiring Valsalva. Herein we reported the case of a young pianist who was attacked by SSEH during piano practice. Playing the piano is a joyful, relaxing entertainment; however, this musical activity can be a highly demanding physical and mental exercise for pianists. Emotional and expressive performance, especially in professional performing, has been reported to result in significant increase of sympathetic and decrease of parasympathetic activities and thus influence the cardiorespiratory variables. The increased biomechanical stress from fluctuating hemodynamics was thought to trigger the rupture of her spinal arteriovenous malformation.
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Mitoflash frequency in early adulthood predicts lifespan in Caenorhabditis elegans.
Nature
PUBLISHED: 01-09-2014
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It has been theorized for decades that mitochondria act as the biological clock of ageing, but the evidence is incomplete. Here we show a strong coupling between mitochondrial function and ageing by in vivo visualization of the mitochondrial flash (mitoflash), a frequency-coded optical readout reflecting free-radical production and energy metabolism at the single-mitochondrion level. Mitoflash activity in Caenorhabditis elegans pharyngeal muscles peaked on adult day 3 during active reproduction and on day 9 when animals started to die off. A plethora of genetic mutations and environmental factors inversely modified the lifespan and the day-3 mitoflash frequency. Even within an isogenic population, the day-3 mitoflash frequency was negatively correlated with the lifespan of individual animals. Furthermore, enhanced activity of the glyoxylate cycle contributed to the decreased day-3 mitoflash frequency and the longevity of daf-2 mutant animals. These results demonstrate that the day-3 mitoflash frequency is a powerful predictor of C.?elegans lifespan across genetic, environmental and stochastic factors. They also support the notion that the rate of ageing, although adjustable in later life, has been set to a considerable degree before reproduction ceases.
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Solution self-assembly and phase transformations of form II crystals in nanoconfined poly(3-hexyl thiophene) based rod-coil block copolymers.
Nanoscale
PUBLISHED: 01-02-2014
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Solution processing of ?-conjugated polymers constitutes a major low-cost manufacturing method for the fabrication of many new organic optoelectronic devices. The solution self-assembly kinetics of ?-conjugated rod-coil block copolymers of symmetric poly(3-hexyl thiophene)-b-poly(2-vinyl pyridine) (P3HT-P2VP) during drying and the phase transformations of the subsequently dried samples were studied by using a combination of TEM, SAXS, WAXS and DSC measurements. During solution drying in chlorobenzene, a good solvent for the copolymer, P3HT-P2VP first formed nanoseed aggregates followed by the directional growth of nanofibrils driven by the formation of prevailing form II P3HT crystals within its nanofibril core confined by the surrounding domain of P2VP blocks. This result was in sharp contrast when a similar molecular weight P3HT homopolymer was solution self-assembled in chlorobenzene, nearly free from confinement, in which case the resulting nanofibrils consisted of a mixture of majority form I and form II crystals. Solvent-cast films of P3HT-P2VP nanofibrils with form II crystals were heat-/cold-treated and showed solid-state phase transformations from form II crystals to form I crystals, both within nanofibrils with annealing, indicating the metastability of the form II crystals with temperature. A disordered state followed with increasing temperatures which, when cooled, induced the formation of a thermodynamically stable lamellar phase with only form I P3HT crystals. Correspondingly, the study provides new strategies for controlling polymorphs and nanostructures of ?-conjugated block copolymers for future applications using solution processing and subsequent heat treatment.
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Elevated soluble VEGF receptor sFlt-1 correlates with endothelial injury in IgA nephropathy.
PLoS ONE
PUBLISHED: 01-01-2014
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Endothelial injury, which may present clinically as hypertension, proteinuria and increased von Willebrand Factor (vWF) level, is a common manifestation in IgA nephropathy (IgAN). However, causal factors for endothelial injury in IgAN are not completely understood. An imbalance of vascular endothelial growth factor/Soluble fms-like tyrosine kinase-1 (VEGF/sFlt-1) has been observed in many diseases with endothelial dysfunction, including pre-eclampsia and diabetic retinopathy, but whether it contributes to endothelial injury in IgAN requires further exploration.
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Nuclear translocation and regulation of intranuclear distribution of cytoplasmic poly(A)-binding protein are distinct processes mediated by two Epstein Barr virus proteins.
PLoS ONE
PUBLISHED: 01-01-2014
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Many viruses target cytoplasmic polyA binding protein (PABPC) to effect widespread inhibition of host gene expression, a process termed viral host-shutoff (vhs). During lytic replication of Epstein Barr Virus (EBV) we observed that PABPC was efficiently translocated from the cytoplasm to the nucleus. Translocated PABPC was diffusely distributed but was excluded from viral replication compartments. Vhs during EBV infection is regulated by the viral alkaline nuclease, BGLF5. Transfection of BGLF5 alone into BGLF5-KO cells or uninfected 293 cells promoted translocation of PAPBC that was distributed in clumps in the nucleus. ZEBRA, a viral bZIP protein, performs essential functions in the lytic program of EBV, including activation or repression of downstream viral genes. ZEBRA is also an essential replication protein that binds to viral oriLyt and interacts with other viral replication proteins. We report that ZEBRA also functions as a regulator of vhs. ZEBRA translocated PABPC to the nucleus, controlled the intranuclear distribution of PABPC, and caused global shutoff of host gene expression. Transfection of ZEBRA alone into 293 cells caused nuclear translocation of PABPC in the majority of cells in which ZEBRA was expressed. Co-transfection of ZEBRA with BGLF5 into BGLF5-KO cells or uninfected 293 cells rescued the diffuse intranuclear pattern of PABPC seen during lytic replication. ZEBRA mutants defective for DNA-binding were capable of regulating the intranuclear distribution of PABPC, and caused PABPC to co-localize with ZEBRA. One ZEBRA mutant, Z(S186E), was deficient in translocation yet was capable of altering the intranuclear distribution of PABPC. Therefore ZEBRA-mediated nuclear translocation of PABPC and regulation of intranuclear PABPC distribution are distinct events. Using a click chemistry-based assay for new protein synthesis, we show that ZEBRA and BGLF5 each function as viral host shutoff factors.
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Twenty-year trends in major cardiovascular risk factors in hospitalized patients with acute myocardial infarction in Beijing.
Chin. Med. J.
PUBLISHED: 11-19-2013
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Hypertension, diabetes mellitus, hypercholesterolaemia and current smoking are the strongest modifiable cardiovascular risk factors for acute myocardial infarction (AMI). We examined their changing trends over the last 20 years.
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Dietary patterns and stomach cancer: a meta-analysis.
Nutr Cancer
PUBLISHED: 10-29-2013
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Investigation of the relationship between dietary patterns and some chronic diseases becomes appealing in nutrition epidemiology. Many studies reported potential associations between different dietary patterns and the risk of stomach cancer, however, a consistent perspective hasnt been established to date. Herein, we carried this meta-analysis to identify the associations between different dietary patterns and the risk of stomach cancer. A total of 23 studies met the inclusion criteria and were included in this meta-analysis. A decreased risk of stomach cancer was shown for the highest compared with the lowest category of a "healthy" dietary pattern [odds ratio (OR) = 0.69; confidence interval (CI): 0.53, 0.89; P = 0.005). There were evidence of the increased risk of stomach cancer in the highest compared with the lowest categories of Western-style pattern (OR = 1.59; CI: 1.25, 2.04; P = 0.0002) and alcohol-drinking pattern (OR = 1.37; CI: 1.11, 1.70; P = 0.004). The results of this meta-analysis indicate that healthy dietary pattern may decrease the risk of stomach cancer, whereas Western-style and alcohol-drinking dietary patterns may increase the risk of stomach cancer.
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Molecular characterization and phylogenetic analysis of three odorant binding protein gene transcripts in Dendrolimus species (Lepidoptera: Lasiocampidae).
Insect Sci.
PUBLISHED: 10-10-2013
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Pine caterpillar moths, Dendrolimus spp. (Lepidoptera: Lasiocampidae), are serious economic pest of pines. Previously, phylogenetic analyses of Dendrolimus using different methods yielded inconsistent results. The chemosensory systems of insects may play fundamental roles in promoting speciation. Odorant-binding proteins (OBPs) participate in the first step of odor detection. Studying the evolution of OBPs in closely related species may help us to identify their role in speciation. We identified three OBPs - one pheromone-binding protein and two general odorant-binding proteins - from male antennae of four Dendrolimus species, D. superans (Butler), D. punctatus (Walker), D. kikuchii Matsumura, and D. houi Lajonquiere, the olfactory recognition systems of which had not been previously investigated. We analyzed their molecular characteristics and compared their sequences to those of OBPs in D. tabulaeformis Tsai et Liu. Ka/Ks ratio analyses among the five Dendrolimus species indicate that PBP1 genes experienced more evolutionary pressure than the GOBPs. Phylogenetic relationships of PBP1 and GOBP1 both indicated that D. houi was the basal species, then branched D. kikuchii, while D. tabulaeformis, D. punctatus, and D. superans evolved more recently. These relationships are consistent with the changes in sex pheromone components of these five species. Dendrolimus tabulaeformis and D. punctatus are closely related sister species. However, the distances among GOBP2 sequences in the five Dendrolimus were very short, and the relationships of D. houi and D. kikuchii could not be resolved. Integrating our results with those of previous studies, we hypothesized that D. kikuchii, D. punctatus and D. superans evolved from the basal ancestor because of sex pheromone mutations and environmental pressure.
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Sample size calculation for differential expression analysis of RNA-seq data under Poisson distribution.
Int J Comput Biol Drug Des
PUBLISHED: 09-30-2013
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Sample size determination is an important issue in the experimental design of biomedical research. Because of the complexity of RNA-seq experiments, however, the field currently lacks a sample size method widely applicable to differential expression studies utilising RNA-seq technology. In this report, we propose several methods for sample size calculation for single-gene differential expression analysis of RNA-seq data under Poisson distribution. These methods are then extended to multiple genes, with consideration for addressing the multiple testing problem by controlling false discovery rate. Moreover, most of the proposed methods allow for closed-form sample size formulas with specification of the desired minimum fold change and minimum average read count, and thus are not computationally intensive. Simulation studies to evaluate the performance of the proposed sample size formulas are presented; the results indicate that our methods work well, with achievement of desired power. Finally, our sample size calculation methods are applied to three real RNA-seq data sets.
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Conjugated polymer/nanoparticles nanocomposites for high efficient and real-time volatile organic compounds sensors.
Anal. Chem.
PUBLISHED: 09-12-2013
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The present work demonstrates a high efficient and low cost volatile organic compounds (VOCs) sensor. Nowadays, VOCs, which are typically toxic, explosive, flammable, and an environmental hazard, are extensively used in R&D laboratories and industrial productions. Real-time and accurately monitoring the presence of harmful VOC during the usage, storage, or transport of VOCs is extremely important which protects humans and the environment from exposure in case of an accident and leakage of VOCs. The present work utilizes conducting polymer/nanoparticles blends to sense various VOCs by detecting the variation of optical properties. The novel sensor features high sensitivity, high accuracy, quick response, and very low cost. Furthermore, it is easy to fabricate into a sensing chip and can be equipped anywhere such as a laboratory or a factory where the VOCs are either used or produced and on each joint between transporting pipes or each switch of VOC storage tanks. Real-time sensing is achievable on the basis of the instant response to VOC concentrations of explosive limits. Therefore, an alarm can be delivered within a few minutes for in time remedies. This research starts from investigating fundamental properties, processing adjustments, and a performance test and finally extends to real device fabrication that practically performs the sensing capability. The demonstrated results significantly advance the current sensor technology and are promising in commercial validity in the near future for human and environmental safety concerns against hazardous VOCs.
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Influences of d-tyrosine on the stability of activated sludge flocs.
Bioresour. Technol.
PUBLISHED: 08-29-2013
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The sludge floc stability is essential for the solid/liquid separation in biological wastewater treatment. In this study, the effect of an exogenous d-tyrosine on the shear stability and surface characteristics of activated sludge flocs was investigated. Sludge flocs were found to be less stable in the addition of d-tyrosine. d-Tyrosine inhibited the production of extracellular polymeric substances (EPS) especially for the proteins. A high correlation coefficient was observed between the composition of EPS fraction and d-tyrosine content. In addition, the hydrophobicity of sludge flocs was reduced and the zeta potential was more negative with the content of d-tyrosine increased. A linear relationship between the extracellular polymeric substances and surface characteristics for sludge flocs indicated that the inhibited EPS production may be responsible for the instability of sludge upon the addition of d-tyrosine.
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A poly(3-hexylthiophene) block copolymer with macroscopically aligned hierarchical nanostructure induced by mechanical rubbing.
Chem. Commun. (Camb.)
PUBLISHED: 08-28-2013
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A highly ordered, uniformly aligned nanostructure with good crystallinity was first achieved on a P3HT block copolymer possessing a low weight fraction (19.4 wt%) of a flexible polyisoprene segment via a mechanical rubbing process without the use of solution based fabrication and thermal annealing. The attachment of the short polyisoprene segment to P3HT would significantly promote the main chain mobility to allow the orientation control of P3HT and of the self-assembled nanostructure by rubbing.
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Factors related with the ability to maintain wakefulness in the daytime after fast and forward rotating shifts.
Kaohsiung J. Med. Sci.
PUBLISHED: 08-12-2013
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The aim of this study was to explore changes in cognitive function, sleep propensity, and sleep-related hormones (growth hormone, cortisol, prolactin, and thyrotropin) and to investigate the factors related to the ability to maintain wakefulness in the daytime after one block of fast forward rotating shift work (2 days, 2 evenings, and 2 nights). Twenty female nurses (mean age: 26.0 ± 2.0 years; range: 22-30 years) were recruited from an acute psychiatric ward. The nurses completed the Maintenance of Wakefulness Test (MWT), State Anxiety Inventory (SAI), Stanford Sleepiness Scale (SSS), Digit Symbol Substitution Test, Symbol Searching Test, Taiwan University Attention Test, Wisconsin Card Sorting Test (WCST), and Multiple Sleep Latency Test (MSLT) four times throughout the day at 2-hour intervals, and their hormone levels were measured at the same time. There was no time of day effect on sleep propensity as measured by the MWT or MSLT despite an increase in self-reported sleepiness. Anxiety state and neuropsychological tasks, including executive function, attention, and perceptual and motor abilities were not affected during the daytime sleep restriction period. The number of omissions and perceptual and motor abilities showed a practice effect. The thyrotropin levels were significantly elevated, and cortisol levels significantly decreased during the daytime sleep restriction period. There were no significant changes in growth hormone or prolactin throughout the daytime period. Age was negatively associated with the mean sleep latency (MSL) of the MWT and positively associated with the MSL of the MSLT. The perseverative errors in WCST and SSS scores were negatively associated with the MSL of the MWT. SAI scores and thyrotropin levels were positively associated with the MSL of the MWT. In conclusion, there was no change in sleep propensity in the daytime after one block of rotating shift work. An attempt to preserve daytime alertness was also related to maintaining neuropsychological performance. Maintaining this ability was related to thyrotropin and age, and this cognition required a high attentive load.
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The effectiveness of an accessibility-enhanced multimedia informational educational programme in reducing anxiety and increasing satisfaction of patients undergoing cardiac catheterisation.
J Clin Nurs
PUBLISHED: 08-04-2013
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To evaluate the effectiveness of an accessibility-enhanced multimedia informational educational programme in reducing anxiety and increasing satisfaction with the information and materials received by patients undergoing cardiac catheterisation.
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Mechanism and control of the structural evolution of a polymer solar cell from a bulk heterojunction to a thermally unstable hierarchical structure.
Nanoscale
PUBLISHED: 07-12-2013
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We simultaneously employed grazing incidence small-angle and wide-angle X-ray scattering (GISAXS and GIWAXS) techniques to quantitatively study the structural evolution and kinetic behavior of poly(3-hexylthiophene) (P3HT) crystallization, [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) aggregation and amorphous P3HT/PCBM domains from a bulk heterojunction (BHJ) to a thermally unstable structure. The independent phase separation regimes on the nanoscale (?10 nm), mesoscale (?100 nm) and macroscale (??m) are revealed for the first time. Bis-PCBM molecules as inhibitors incorporated into the P3HT/PCBM blend films were adopted as a case study of a control strategy for improving the thermal stability of P3HT/PCBM solar cell. The detailed information on the formation, growth, transformation and mutual interaction between different phases during the hierarchical structural evolution of P3HT/PCBM:xbis-PCBM (x = 8-100%) blend films are presented herein. This systematic study proposes the mechanisms of thermal instability for a polymer/fullerene-based solar cell. We demonstrate a new fundamental concept that the structural evolution and thermal stability of mesoscale amorphous P3HT/PCBM domains during heating are the origin of controlling thermal instability rather than those of nanoscale thermally-stable BHJ structures. It leads to a low-cost and easy-fabrication control strategy for effectively tailoring the hierarchical morphology against thermal instability from molecular to macro scales. The optimum treatment achieving high thermal stability, control of mesoscale domains, can be effectively designed. It is independent of the original BHJ nanostructure design of a polymer/fullerene-based solar cell with high performance. It advances the general knowledge on the thermal instability directly arising from the nanoscale structure.
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Marginal regression approach for additive hazards models with clustered current status data.
Stat Med
PUBLISHED: 06-17-2013
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Current status data arise naturally from tumorigenicity experiments, epidemiology studies, biomedicine, econometrics and demographic and sociology studies. Moreover, clustered current status data may occur with animals from the same litter in tumorigenicity experiments or with subjects from the same family in epidemiology studies. Because the only information extracted from current status data is whether the survival times are before or after the monitoring or censoring times, the nonparametric maximum likelihood estimator of survival function converges at a rate of n(1?3) to a complicated limiting distribution. Hence, semiparametric regression models such as the additive hazards model have been extended for independent current status data to derive the test statistics, whose distributions converge at a rate of n(1?2) , for testing the regression parameters. However, a straightforward application of these statistical methods to clustered current status data is not appropriate because intracluster correlation needs to be taken into account. Therefore, this paper proposes two estimating functions for estimating the parameters in the additive hazards model for clustered current status data. The comparative results from simulation studies are presented, and the application of the proposed estimating functions to one real data set is illustrated. Copyright © 2013 John Wiley & Sons, Ltd.
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Nitrous oxide and methane emissions from optimized and alternative cereal cropping systems on the North China Plain: A two-year field study.
Sci. Total Environ.
PUBLISHED: 06-16-2013
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The impacts of different crop rotation systems with their corresponding management practices on grain yield, greenhouse gas emissions, and fertilizer nitrogen (N) and irrigation water use efficiencies are not well documented. This holds especially for the North China Plain which provides the staple food for hundreds of millions of people and where groundwater resources are polluted with nitrate and depleted through irrigation. Here, we report on fertilizer N and irrigation water use, grain yields, and nitrous oxide (N2O) and methane (CH4) emissions of conventional and optimized winter wheat-summer maize double-cropping systems, and of three alternative cropping systems, namely a winter wheat-summer maize (or soybean)-spring maize system, with three harvests in two years; and a single spring maize system with one crop per year. The results of this two-year study show that the optimized double-cropping system led to a significant increase in grain yields and a significant decrease in fertilizer N use and net greenhouse gas intensity, but the net greenhouse gas N2O emissions plus CH4 uptake and the use of irrigation water did not decrease relative to the conventional system. Compared to the conventional system the net greenhouse gas emissions, net greenhouse gas intensity and use of fertilizer N and irrigation water decreased in the three alternative cropping systems, but at the cost of grain yields except in the winter wheat-summer maize-spring maize system. Net uptake of CH4 by the soil was little affected by cropping system. Average N2O emission factors were only 0.17% for winter wheat and 0.53% for maize. In conclusion, the winter wheat-summer maize-spring maize system has considerable potential to decrease water and N use and decrease N2O emissions while maintaining high grain yields and sustainable use of groundwater.
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Identification of patients with nasopharyngeal carcinoma by serum protein profiling using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry.
Int. J. Clin. Oncol.
PUBLISHED: 06-14-2013
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As diagnosis of nasopharyngeal carcinoma at an early disease stage is important, we attempted to distinguish between patients with nasopharyngeal carcinoma and noncancer controls by using serum protein profiles.
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Sample size calculation based on exact test for assessing differential expression analysis in RNA-seq data.
BMC Bioinformatics
PUBLISHED: 06-03-2013
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Sample size calculation is an important issue in the experimental design of biomedical research. For RNA-seq experiments, the sample size calculation method based on the Poisson model has been proposed; however, when there are biological replicates, RNA-seq data could exhibit variation significantly greater than the mean (i.e. over-dispersion). The Poisson model cannot appropriately model the over-dispersion, and in such cases, the negative binomial model has been used as a natural extension of the Poisson model. Because the field currently lacks a sample size calculation method based on the negative binomial model for assessing differential expression analysis of RNA-seq data, we propose a method to calculate the sample size.
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Characterization of the interactions between tetracycline antibiotics and microbial extracellular polymeric substances with spectroscopic approaches.
Environ Sci Pollut Res Int
PUBLISHED: 06-03-2013
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The antibiotics have attracted global attentions for their impact on aquatic ecosystem. The knowledge about the fate of antibiotics encountering extracellular polymeric substances (EPS) is, however, limited. In this study, we investigated the interacting mechanisms of tetracycline (TC) to EPS extracted from aerobic activated sludge. The contributions of the main components of EPS, extracellular proteins, and polysaccharides were evaluated using bovine serum albumin and alginate sodium, respectively. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and nuclear magnetic resonance indicated that hydroxyl, carboxyl, and amino groups were the domain chemical groups involved in the interaction between TC and EPS, and the binding of TC onto EPS changed the structure of these chemical groups, thus causing shifts in their UV-visible absorption spectra. In addition, we found that extracellular proteins, rather than polysaccharides, were the major active contents involved in the interaction. Three-dimensional excitation-emission matrix fluorescence spectroscopy showed that the fluorophores in EPS were clearly quenched by TC and the static quenching process was observed, implying the complex formation of TC and EPS. Furthermore, thermodynamic analysis indicated that the binding of TC with EPS is spontaneous and dominated by electrostatic forces.
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[Differentially expressed protelns in serum among different Chinese medical syndrome types of primary liver cancer in the perloperatlve period of interventional treatment].
Zhongguo Zhong Xi Yi Jie He Za Zhi
PUBLISHED: 05-30-2013
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To explore different expressions of serum proteins among different Chinese medical syndrome types of primary liver cancer (PLC) in the perioperative period of interventional treatment, and to explore its significance.
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[Progress in application of microbeam X-ray fluorescence spectroscopy in forensic science].
Fa Yi Xue Za Zhi
PUBLISHED: 05-08-2013
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Microbeam X-ray fluorescence (micro-XRF) spectrometry has been raised as an analytical technique of microbeam during the recent years. With its advantages of high sensitivity, small sample requirement, high testing accuracy and non-destruction, the technique is widely utilized in forensic science. This review bases on recent researches at home and abroad, describes its applications including identification of gunshot residue, visualization of fingerprints, discrimination of drug source, production process, and other material evidences of analysis in crime scene. Thanks to the advances in technology, intelligent and portable micro-XRF equipment has appeared to be applied. It is believed that it may be more popular and frequent in administration of forensic science in the near future.
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Genome-wide annotation, expression profiling, and protein interaction studies of the core cell-cycle genes in Phalaenopsis aphrodite.
Plant Mol. Biol.
PUBLISHED: 04-23-2013
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Orchidaceae is one of the most abundant and diverse families in the plant kingdom and its unique developmental patterns have drawn the attention of many evolutionary biologists. Particular areas of interest have included the co-evolution of pollinators and distinct floral structures, and symbiotic relationships with mycorrhizal flora. However, comprehensive studies to decipher the molecular basis of growth and development in orchids remain scarce. Cell proliferation governed by cell-cycle regulation is fundamental to growth and development of the plant body. We took advantage of recently released transcriptome information to systematically isolate and annotate the core cell-cycle regulators in the moth orchid Phalaenopsis aphrodite. Our data verified that Phalaenopsis cyclin-dependent kinase A (CDKA) is an evolutionarily conserved CDK. Expression profiling studies suggested that core cell-cycle genes functioning during the G1/S, S, and G2/M stages were preferentially enriched in the meristematic tissues that have high proliferation activity. In addition, subcellular localization and pairwise interaction analyses of various combinations of CDKs and cyclins, and of E2 promoter-binding factors and dimerization partners confirmed interactions of the functional units. Furthermore, our data showed that expression of the core cell-cycle genes was coordinately regulated during pollination-induced reproductive development. The data obtained establish a fundamental framework for study of the cell-cycle machinery in Phalaenopsis orchids.
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Omniphobic low moisture permeation transparent polyacrylate/silica nanocomposite.
ACS Appl Mater Interfaces
PUBLISHED: 04-11-2013
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We report the development of low moisture permeation and transparent dense polyacrylate/silica nanocomposite material that can exhibit both superhydrophobic and oleophobic (omniphobic) properties. The material was prepared by a three-step process. The first step involved the preparation of UV polymerizable solventless hybrid resin and the fabrication of nanocomposite. The hybrid resin consisted of a mixture of acrylate monomer, initiator, and acrylate-modified different size silica nanoparticles. The second step was to roughen the surface of the nanocomposite with unique nanotexture by oxygen plasma. In the third step, we applied a low surface tension fluoro monolayer on the treated surface. The nanocomposite exhibits desired superhydrophobicity and oleophobicity with a water contact angle of 158.2° and n-1-octadecene contact angle of 128.5°, respectively; low moisture permeation of 1.44 g·mm/m(2)·day; and good transparency (greater than 82% at 450-800 nm for ~60 ?m film). The material has potential applications in optoelectronic encapsulation, self-cleaning coating, etc.
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Identification of targetable FGFR gene fusions in diverse cancers.
Cancer Discov
PUBLISHED: 04-04-2013
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Through a prospective clinical sequencing program for advanced cancers, four index cases were identified which harbor gene rearrangements of FGFR2, including patients with cholangiocarcinoma, breast cancer, and prostate cancer. After extending our assessment of FGFR rearrangements across multiple tumor cohorts, we identified additional FGFR fusions with intact kinase domains in lung squamous cell cancer, bladder cancer, thyroid cancer, oral cancer, glioblastoma, and head and neck squamous cell cancer. All FGFR fusion partners tested exhibit oligomerization capability, suggesting a shared mode of kinase activation. Overexpression of FGFR fusion proteins induced cell proliferation. Two bladder cancer cell lines that harbor FGFR3 fusion proteins exhibited enhanced susceptibility to pharmacologic inhibition in vitro and in vivo. Because of the combinatorial possibilities of FGFR family fusion to a variety of oligomerization partners, clinical sequencing efforts, which incorporate transcriptome analysis for gene fusions, are poised to identify rare, targetable FGFR fusions across diverse cancer types.
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Induction chemotherapy followed by concurrent chemoradiotherapy versus concurrent chemoradiotherapy with or without adjuvant chemotherapy for locoregionally advanced nasopharyngeal carcinoma: meta-analysis of 1,096 patients from 11 randomized controlled t
Asian Pac. J. Cancer Prev.
PUBLISHED: 03-29-2013
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To evaluate the efficacy and toxicity of induction chemotherapy followed by concurrent chemoradiotherapy (the treatment group) versus concurrent chemoradiotherapy with or without adjuvant chemotherapy (the control group) for locoregionally advanced nasopharyngeal carcinoma.
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Poly(ADP-ribose) polymerase-1 regulates the mechanism of irradiation-induced CNE-2 human nasopharyngeal carcinoma cell autophagy and inhibition of autophagy contributes to the radiation sensitization of CNE-2 cells.
Oncol. Rep.
PUBLISHED: 03-19-2013
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The aim of the present study was to investigate the role of autophagy in response to ionizing radiation (IR) in CNE-2 human nasopharyngeal carcinoma cells and to demonstrate the function of poly(ADP-ribose) polymerase-1 (PARP-1) in the regulation of IR-induced autophagy. Microtubule-associated protein 1 light chain 3 (LC3) and poly(ADP-ribose) (PAR) were assessed using western blotting. Ultrastructural analysis was performed using transmission electron microscopy (TEM). The percentage of apoptotic cells was assessed by flow cytometry. The MTT method was used to detect cell viability of CNE-2 cells at different time points after IR. Clonogenic survival assays were used to evaluate the radiosensitivity of nasopharyngeal carcinoma cells treated with IR and IR combined with autophagy inhibitor (chloroquine phosphate), with autophagy inducer (rapamycin) or with PARP-1 inhibitor 3-amino benzamide (3AB). IR induced a massive accumulation of autophagosomes detected by TEM and intensified the conversion of cytosolic LC3-I to LC3-II. PARP-1 activation was accompanied by strong upregulation of PAR and LC3-II expression in CNE-2 cells. Compared with radiation alone, chloroquine phosphate (CDP) or 3AB combined with IR significantly decreased cell viability, as well as the autophagic ratio and LC3-II protein levels. Inhibition of autophagy increased radiation-induced apoptosis; rapamycin (RAPA) significantly decreased cell viability as well, but RAPA increased the autophagic ratio and LC3-II protein levels; induction of autophagy increased radiation-induced apoptosis. To conclude, PARP-1 regulates IR-induced autophagy, and PARP-1 inhibitor contributes to the radiation sensitization of CNE-2 cells. Blockade of autophagy with CDP enhanced the cytotoxicity of radiotherapy in CNE-2 cells. This suggests that inhibition of autophagy or PARP-1 may be used as an adjuvant therapy to treat nasopharyngeal carcinoma.
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Synergistic analgesic effects between neuronostatin and morphine at the supraspinal level.
Peptides
PUBLISHED: 03-10-2013
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Neuronostatin, a 13-amino acid peptide, is encoded in the somatostatin pro-hormone. I.c.v. administration of neuronostatin produces a significant antinociceptive effect in the mouse tail-flick test, which is mediated by endogenous opioid receptor. However, the direct functional interaction between morphine and neuronostatin has not been characterized. In the present study, effect of neuronostatin on morphine analgesia was investigated in the tail-flick test. Our findings showed that i.c.v. administration of neuronostatin (0.3nmol/mouse i.c.v.) significantly enhanced the antinociceptive effect of morphine (2.5, 5 or 10?g/kg) at the supraspinal level. Results of antagonism experiments suggested that the synergistic analgesia induced by morphine and neuronostatin was mediated by ?- and ?-opioid receptors not ?-opioid receptor. In conclusion, there may be a cascade amplification phenomenon when morphine and neuronostatin were co-administered in acute pain model. The above results provide evidence for the potential use of neuronostatin in combination with morphine to control pain and addiction.
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Nurses working on fast rotating shifts overestimate cognitive function and the capacity of maintaining wakefulness during the daytime after a rotating shift.
Sleep Med.
PUBLISHED: 02-28-2013
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The objective of our study was to explore changes in cognitive functions, sleep propensity, and sleep-related hormones (growth hormone [GH], cortisol, prolactin [PRL], thyrotropin [TSH]) in the daytime of nurses working on fast rotating shifts.
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Silencing glucose-regulated protein 78 induced renal cell carcinoma cell line G1 cell-cycle arrest and resistance to conventional chemotherapy.
Urol. Oncol.
PUBLISHED: 02-18-2013
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Glucose-regulated protein 78 (Grp78) is an endoplasmic reticulum chaperone; it maintains endoplasmic reticulum homeostasis and modulates unfolded protein response. The protein is overexpressed in various cancer types, including renal cell carcinoma (RCC). Increased Grp78 expression in patients with RCC is correlated with more aggressive tumors and poorer prognoses. This study investigated the role of Grp78 in regulating tumorigenesis and evaluated the potential of Grp78-targeted therapy for RCC.
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Early assessment of breast cancer response to neoadjuvant chemotherapy by semi-quantitative analysis of high-temporal resolution DCE-MRI: preliminary results.
Magn Reson Imaging
PUBLISHED: 02-12-2013
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To evaluate whether semi-quantitative analysis of high temporal resolution dynamic contrast-enhanced MRI (DCE-MRI) acquired early in treatment can predict the response of locally advanced breast cancer (LABC) to neoadjuvant chemotherapy (NAC).
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Resting-state brain activity in major depressive disorder patients and their siblings.
J Affect Disord
PUBLISHED: 02-07-2013
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Major depressive disorder (MDD) is a highly heritable psychiatric disease, and the existing literature is not robust enough to allow us to evaluate whether MDD-associated biomarkers are state-independent heritable endophenotypes or state markers related to depression per se.
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Association between single nucleotide polymorphisms of the transforming growth factor-?1 gene and overall survival in unresectable locally advanced non-small-cell lung cancer patients treated with radio(chemo)therapy in a Chinese population.
Med. Oncol.
PUBLISHED: 02-06-2013
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The outcome is variable for unresectable locally advanced non-small-cell lung cancer (ULANSCLC) patients treated with radio(chemo)therapy. The aim of this study is to investigate whether single-nucleotide polymorphisms (SNPs) in the transforming growth factor-beta1 (TGF-?1) gene are associated with overall survival (OS) in ULANSCLC patients treated with definitive radio(chemo)therapy. A total of 109 patients who had available blood samples and complete clinical and follow-up information were enrolled. DNA from blood was genotyped for two SNPs: TGF-?1 C-509T and T+869C. Kaplan-Meier survival analysis, log-rank test, and Coxs proportional hazard model were used to evaluate associations between genotypes and OS. Log-rank test showed that TGF-?1 C-509T significantly correlated with OS (pooled P = 0.017). Both univariate and multivariate analyses showed that TGF-?1 C-509T CC genotype was significantly associated with better OS than CT or TT genotypes. These results indicate that TGF-?1 C-509T CC genotype is significantly associated with better OS in ULANSCLC patients treated with radio(chemo)therapy as a potential independent survival predictor.
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Molecular structure effect of pyridine-based surface ligand on the performance of P3HT:TiO? hybrid solar cell.
ACS Appl Mater Interfaces
PUBLISHED: 01-29-2013
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Colloid TiO(2) nanorods are used for solution-processable poly(3-hexyl thiophene): TiO(2) hybrid solar cell. The nanorods were covered by insulating ligand of oleic acid (OA) after sol-gel synthesis. Three more conducting pyridine type ligands: pyridine, 2,6-lutidine (Lut) and 4-tert-butylpyridine (tBP) were investigated respectively to replace OA. The power conversion efficiency (PCE) of the solar cell was increased because the electronic mobility of pyridine-type ligand-modified TiO(2) is higher than that of TiO(2)-OA. The enhancement of PCE is in the descending order of Lut > pyridine > tBP because of the effective replacement of OA by Lut. The PCE of solar cell can be further enhanced by ligand exchange of pyridine type ligand with conjugating molecule of 2-cyano-3-(5-(7-(thiophen-2-yl)-benzothiadiazol-4-yl) thiophen-2-yl) acrylic acid (W4) on TiO(2) nanorods because W4 has aligned bandgap with P3HT and TiO(2) to facilitate charge separation and transport. The electronic mobility of two-stage ligand exchanged TiO(2) is improved furthermore except Lut, because it adheres well and difficult to be replaced by W4. The amount of W4 on TiO(2)-tBP is 3 times more than that of TiO(2)-Lut (0.20 mol % vs. 0.06 mol %). Thus, the increased extent of PCE of solar cell is in the decreasing order of tBP > pyridine > Lut. The TiO(2)-tBP-W4 device has the best performance with 1.4 and 2.6 times more than TiO(2)-pyridine-W4 and TiO(2)-Lut-W4 devices, respectively. The pKa of the pyridine derivatives plays the major role to determine the ease of ligand exchange on TiO(2) which is the key factor mandating the PCE of P3HT:TiO(2) hybrid solar cell. The results of this study provide new insights of the significance of acid-base reaction on the TiO(2) surface for TiO(2)-based solar cells. The obtained knowledge can be extended to other hybrid solar cell systems.
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Greenhouse gas emissions from a wheat-maize double cropping system with different nitrogen fertilization regimes.
Environ. Pollut.
PUBLISHED: 01-21-2013
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Here, we report on a two-years field experiment aimed at the quantification of the emissions of nitrous oxide (N2O) and methane (CH4) from the dominant wheat-maize double cropping system in North China Plain. The experiment had 6 different fertilization strategies, including a control treatment, recommended fertilization, with and without straw and manure applications, and nitrification inhibitor and slow release urea. Application of N fertilizer slightly decreased CH4 uptake by soil. Direct N2O emissions derived from recommended urea application was 0.39% of the annual urea-N input. Both straw and manure had relatively low N2O emissions factors. Slow release urea had a relatively high emission factor. Addition of nitrification inhibitor reduced N2O emission by 55%. We conclude that use of nitrification inhibitors is a promising strategy for N2O mitigation for the intensive wheat-maize double cropping systems.
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Microvascular decompression for classic trigeminal neuralgia: determination of minimum clinically important difference in pain improvement for patient reported outcomes.
Neurosurgery
PUBLISHED: 01-19-2013
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Outcomes studies use patient-reported outcome (PRO) measurements to assess treatment effectiveness, but can lack direct clinical meaning. Minimum clinically important difference (MCID) calculation provides a point estimate of the critical threshold needed to achieve clinically relevant treatment effectiveness. MCID remains uninvestigated for microvascular decompression (MVD), a common surgical procedure for trigeminal neuralgia.
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Pulmonary hypertension risk in patients with hemoglobin h disease: low incidence and absence of correlation with splenectomy.
Acta Haematol.
PUBLISHED: 01-14-2013
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Pulmonary hypertension (PHT) is a common complication for patients with ? thalassemia intermediate (TI), especially splenectomized patients. However, the frequency and risk factors of PHT in patients with hemoglobin H (HbH) disease is unknown. The purpose of this study was to identify the prevalence of PHT risk manifested as tricuspid regurgitant jet velocity (TRV) ?2.5 m/s in patients with HbH disease and its correlation with splenectomy. One hundred and ninety-eight patients with HbH disease who visited the 303rd Hospital of the Peoples Liberation Army (Nanning, China) were investigated. Thirteen subjects (6.5%) were diagnosed as having a risk of PHT. Regression analyses showed that the prevalence of PHT risk was correlated only with age (r = 0.195, p = 0.006) and not with splenectomy. The risk of PHT in patients older than 35 years was 5.7 times (range 1.8-18.6) greater than that for patients younger than 35 years. For splenectomized patients compared to those with HbH disease, patients with TI had a higher frequency of PHT risk, higher nucleated red blood cell counts (46.03 ± 41.11 × 10(9)/l vs. 0.18 ± 1.19 × 10(9)/l, p < 0.001) and a higher platelet counts (837.6 ± 178.9 × 10(9)/l vs. 506.7 ± 146.2 × 10(9)/l, p < 0.001). PHT risk is low in patients with HbH disease and does not correlate with splenectomy. Patients older than 35 years should be monitored regularly.
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Sleep Quality among Female Hospital Staff Nurses.
Sleep Disord
PUBLISHED: 01-13-2013
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Purpose. To investigate sleep quality of hospital staff nurses, both by subjective questionnaire and objective measures. Methods. Female staff nurses at a regional teaching hospital in Northern Taiwan were recruited. The Chinese version of the pittsburgh sleep quality index (C-PSQI) was used to assess subjective sleep quality, and an electrocardiogram-based cardiopulmonary coupling (CPC) technique was used to analyze objective sleep stability. Work stress was assessed using questionnaire on medical workers stress. Results. A total of 156 staff nurses completed the study. Among the staff nurses, 75.8% (117) had a PSQI score of ?5 and 39.8% had an inadequate stable sleep ratio on subjective measures. Nurses with a high school or lower educational degree had a much higher risk of sleep disturbance when compared to nurses with a college or higher level degree. Conclusions. Both subjective and objective measures demonstrated that poor sleep quality is a common health problem among hospital staff nurses. More studies are warranted on this important issue to discover possible factors and therefore to develop a systemic strategy to cope with the problem.
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Acupressure improves sleep quality of psychogeriatric inpatients.
Nurs Res
PUBLISHED: 01-11-2013
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Acupressure, a noninvasive form of acupuncture, may be used as a low-cost and noninvasive means of improving sleep quality. Although it has been evaluated to improve self-reported sleep quality, it has not been assessed with regard to effectiveness in improving perceived and objective measures of sleep quality outcomes.
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Band gap engineering via controlling donor-acceptor compositions in conjugated copolymers.
J Phys Chem B
PUBLISHED: 01-02-2013
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Varying composition of ?-donor/acceptor moieties has been considered as an effective strategy for fine-tuning of the electronic properties of D-A conjugated copolymers. In this study, the change of optoelectronic properties with the change of donor/acceptor ratios is investigated on the basis of first-principles density functional calculations. Copolymers containing moieties of similar ?-electron donating and/or accepting capabilities, e.g., thiophene (T)-methoxythiophene (OT), exhibit a linear dependence of electronic properties (especially, HOMO/LUMO, band gap, and bandwidth) on the D/A content. In contrast, for strong D/A contrast systems, e.g., thiophene (T)-thienopyrazine (TP), the electronic properties vary nonlinearly with D/A compositions. However, when the block size of one parent monomer in a strong D/A contrast system is fixed, the variation of electronic properties shows a remarkable linear correlation against D/A compositions. We found that the deviation of electronic properties from a linear composition dependence is dominated by the strength of orbital interactions between D and A. Weak orbital interactions between D and A moieties tend to lead to a nonlinear composition dependence. Our results provide useful insights for band gap tuning through the adjustment of D/A compositions in D-A conjugated copolymers.
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