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Find video protocols related to scientific articles indexed in Pubmed.
Glycogen synthase kinase-3: a key kinase in retinal neuron apoptosis in early diabetic retinopathy.
Chin. Med. J.
PUBLISHED: 10-02-2014
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Diabetes-related pathogenic factors can cause retinal ganglion cell (RGC) apoptosis, but the specific mechanism is not very clear. The aim of this study is to investigate the correlation between glycogen synthase kinase-3 (GSK-3) activation and retinal neuron apoptosis.
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Spatially confined assembly of nanoparticles.
Acc. Chem. Res.
PUBLISHED: 09-22-2014
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Conspectus The ability to assemble NPs into ordered structures that are expected to yield collective physical or chemical properties has afforded new and exciting opportunities in the field of nanotechnology. Among the various configurations of nanoparticle assemblies, two-dimensional (2D) NP patterns and one-dimensional (1D) NP arrays on surfaces are regarded as the ideal assembly configurations for many technological devices, for example, solar cells, magnetic memory, switching devices, and sensing devices, due to their unique transport phenomena and the cooperative properties of NPs in assemblies. To realize the potential applications of NP assemblies, especially in nanodevice-related applications, certain key issues must still be resolved, for example, ordering and alignment, manipulating and positioning in nanodevices, and multicomponent or hierarchical structures of NP assemblies for device integration. Additionally, the assembly of NPs with high precision and high levels of integration and uniformity for devices with scaled-down dimensions has become a key and challenging issue. Two-dimensional NP patterns and 1D NP arrays are obtained using traditional lithography techniques (top-down strategies) or interfacial assembly techniques (bottom-up strategies). However, a formidable challenge that persists is the controllable assembly of NPs in desired locations over large areas with high precision and high levels of integration. The difficulty of this assembly is due to the low efficiency of small features over large areas in lithography techniques or the inevitable structural defects that occur during the assembly process. The combination of self-assembly strategies with existing nanofabrication techniques could potentially provide effective and distinctive solutions for fabricating NPs with precise position control and high resolution. Furthermore, the synergistic combination of spatially mediated interactions between nanoparticles and prestructures on surfaces may play an increasingly important role in the controllable assembly of NPs. In this Account, we summarize our approaches and progress in fabricating spatially confined assemblies of NPs that allow for the positioning of NPs with high resolution and considerable throughput. The spatially selective assembly of NPs at the desired location can be achieved by various mechanisms, such as, a controlled dewetting process, electrostatically mediated assembly of particles, and confined deposition and growth of NPs. Three nanofabrication techniques used to produce prepatterns on a substrate are summarized: the Langmuir-Blodgett (LB) patterning technique, e-beam lithography (EBL), and nanoimprint lithography (NPL). The particle density, particle size, or interparticle distance in NP assemblies strongly depends on the geometric parameters of the template structure due to spatial confinement. In addition, with smart design template structures, multiplexed NPs can be assembled into a defined structure, thus demonstrating the structural and functional complexity required for highly integrated and multifunction applications.
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Effect of in-office bleaching agents on the color changes of stained ceromers and direct composite resins.
Acta Odontol. Scand.
PUBLISHED: 09-08-2014
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Abstract Purpose. To evaluate the effect of two in-office bleaching agents on the color changes of two ceromers (Ceramage and Adoro SR) and one direct composite resin (Gradia Direct Anterior) after staining by tea and coffee. Materials and methods. Twenty-four disk-shaped specimens were fabricated for each resin material and randomly divided into three groups (n = 8). The specimens were immersed in tea, coffee or deionized water, respectively, for 7 days. Each group was then equally divided into two sub-groups (n = 4), which were subjected to two in-office bleaching agents (BEYOND and Opalescence Boost), respectively. The color of the specimens was measured by a spectrophotometer at baseline, after staining and after bleaching. The color differences (?E values) between baseline and after treatments were calculated. Results. Statistical analysis indicated that the staining solution had significant influence on the color change of resin composites tested (p < 0.001). The discolorations of resin composites were perceptible after immersing in tea or coffee solutions (?E>2.0). There was no statistically significant difference between BEYOND and Opalescence Boost in stains removal from discolored resins (p = 0.550). The color changes in ?E value between baseline and after bleaching were less than 2.0 for all resin composite groups. Conclusions. Tea solution produces severe discoloration of three resin composites tested. The two in-office bleaching agents can effectively remove the stains from two ceromers and one direct composite resin tested in this study.
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Unravelling the Correlation between the Aspect Ratio of Nanotubular Structures and Their Electrochemical Performance To Achieve High-Rate and Long-Life Lithium-Ion Batteries.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 08-28-2014
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The fundamental understanding of the relationship between the nanostructure of an electrode and its electrochemical performance is crucial for achieving high-performance lithium-ion batteries (LIBs). In this work, the relationship between the nanotubular aspect ratio and electrochemical performance of LIBs is elucidated for the first time. The stirring hydrothermal method was used to control the aspect ratio of viscous titanate nanotubes, which were used to fabricate additive-free TiO2 -based electrode materials. We found that the battery performance at high charging/discharging rates is dramatically boosted when the aspect ratio is increased, due to the optimization of electronic/ionic transport properties within the electrode materials. The proof-of-concept LIBs comprising nanotubes with an aspect ratio of 265 can retain more than 86?% of their initial capacity over 6000 cycles at a high rate of 30?C. Such devices with supercapacitor-like rate performance and battery-like capacity herald a new paradigm for energy storage systems.
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A novel material of cross-linked styrylpyridinium salt intercalated montmorillonite for drug delivery.
Nanoscale Res Lett
PUBLISHED: 08-03-2014
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A facile synthesis of a styrylpyridinium salt (SbQ)/montmorillonite (MMT) via cationic exchange interactions between styrylpyridinium species (specifically SbQ) and MMT platelets is reported in this work. The SbQ-MMT solutions were irradiated under ultraviolet (UV) light for a specific time to obtain the cross-linked SbQ-MMT materials. Scanning electron microscopy and atomic force microscopy analyses revealed the structures and morphologies of MMT and modified MMT. X-ray diffraction and transmission electron microscope analyses indicated that the basal spacing increased from 1.24 to 1.53 nm compared with the pristine MMT, which proved that SbQ had interacted with MMT. Thermal gravimetric analysis curves showed that the amount of SbQ in the MMT interlayers was 35.71 meq/100 g. Fourier transform infrared spectroscopy also confirmed the intercalation of SbQ species into MMT interlayers, and UV spectroscopy was used to follow up the cross-linking of SbQ-MMT. This novel material has potential applications in drug delivery, and it can also be used as an additive to improve the mechanical properties of polymers.
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Geographical and seasonal patterns of geosmin and 2-methylisoborneol in environmental water in jiangsu province of china.
J Anal Methods Chem
PUBLISHED: 07-31-2014
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This study was conducted to obtain the basic data of two common odorants-geosmin and 2-methylisoborneol (GSM and 2-MIB)-in environmental water. More specifically, the headspace solid-phase microextraction coupled to gas chromatography mass spectrometry (HS-SPME/GC-MS) was applied to determine the levels of GSM and 2-MIB in water samples, and the samples were collected depending on water sources, conventional treatment processes, and seasons. The significant difference was shown for the 2-MIB levels of source water (P < 0.05), the concentrations of GSM and 2-MIB decreased significantly as treatment process of tap water moved forward (P < 0.0001), and the significant differences for the levels of GSM and 2-MIB were observed among three sampling periods (P < 0.01). The levels of GSM and 2-MIB in all water samples were lower than 10?ng?L(-1), the odor threshold concentration (OTC), and the conventional treatment process plays a significant role in removing odorants in tap water.
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Computational analysis of microbubble flows in bifurcating airways: role of gravity, inertia, and surface tension.
J Biomech Eng
PUBLISHED: 07-30-2014
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Although mechanical ventilation is a life-saving therapy for patients with severe lung disorders, the microbubble flows generated during ventilation generate hydrodynamic stresses, including pressure and shear stress gradients, which damage the pulmonary epithelium. In this study, we used computational fluid dynamics to investigate how gravity, inertia, and surface tension influence both microbubble flow patterns in bifurcating airways and the magnitude/distribution of hydrodynamic stresses on the airway wall. Direct interface tracking and finite element techniques were used to simulate bubble propagation in a two-dimensional (2D) liquid-filled bifurcating airway. Computational solutions of the full incompressible Navier-Stokes equation were used to investigate how inertia, gravity, and surface tension forces as characterized by the Reynolds (Re), Bond (Bo), and Capillary (Ca) numbers influence pressure and shear stress gradients at the airway wall. Gravity had a significant impact on flow patterns and hydrodynamic stress magnitudes where Bo?>?1 led to dramatic changes in bubble shape and increased pressure and shear stress gradients in the upper daughter airway. Interestingly, increased pressure gradients near the bifurcation point (i.e., carina) were only elevated during asymmetric bubble splitting. Although changes in pressure gradient magnitudes were generally more sensitive to Ca, under large Re conditions, both Re and Ca significantly altered the pressure gradient magnitude. We conclude that inertia, gravity, and surface tension can all have a significant impact on microbubble flow patterns and hydrodynamic stresses in bifurcating airways.
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Angiogenin: a potential serum marker of infantile hemangioma revealed by cDNA microarray analysis.
Plast. Reconstr. Surg.
PUBLISHED: 07-29-2014
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Hemangiomas are characterized by rapid growth but slow regression. Prognosis and treatment urgently require the identification of serum markers to determine the proliferative potential of hemangiomas.
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Plasticity of mesenchymal stem cells in immunomodulation: pathological and therapeutic implications.
Nat. Immunol.
PUBLISHED: 07-01-2014
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Mesenchymal stem cells (MSCs) are multipotent stromal cells that exist in many tissues and are capable of differentiating into several different cell types. Exogenously administered MSCs migrate to damaged tissue sites, where they participate in tissue repair. Their communication with the inflammatory microenvironment is an essential part of this process. In recent years, much has been learned about the cellular and molecular mechanisms of the interaction between MSCs and various participants in inflammation. Depending on their type and intensity, inflammatory stimuli confer on MSCs the ability to suppress the immune response in some cases or to enhance it in others. Here we review the current findings on the immunoregulatory plasticity of MSCs in disease pathogenesis and therapy.
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MicroRNA-216a inhibits pancreatic cancer by directly targeting Janus kinase 2.
Oncol. Rep.
PUBLISHED: 06-12-2014
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MicroRNA (miR)-216a expression is significantly downregulated in human pancreatic cancer, however, the underlying mechanism remains unknown. In the present study, we aimed to identify and characterize the direct target gene and potential function of miR-216a in pancreatic cancer cells. Bioinformatics analysis and dual-luciferase reporter gene assay showed that Janus kinase 2 (JAK2) was a direct target gene of miR-216a. Quantitative polymerase chain reaction and western blot analysis demonstrated that miR-216a decreased the mRNA and protein levels of JAK2 in pancreatic cancer cells. Phosphorylation of the signal transducer and activator of transcription 3 (STAT3) was also downregulated by miR-216a, whereas the anti-miR-216a treatment had an opposite effect. Treatment of pancreatic cancer cells with miR-216a significantly inhibited cell growth and promoted cell apoptosis. In addition, the downstream genes of JAK2/STAT3, survivin and X-linked inhibitor of apoptosis protein, which are anti?apoptotic genes, were also decreased by miR-216a. Moreover, miR-216a overexpression markedly inhibited the JAK2/STAT3 signaling pathway and xenograft tumor growth in vivo. Compared with miR-216a treatment, anti-miR-216a treatment exhibited opposite effects throughout the entire experiment, confirming the inhibitory effect of miR-216a on pancreatic cancer by regulating the JAK2/STAT3 signaling pathway. The results provided evidence that miR-216a targeting JAK2 negatively regulated the development of pancreatic cancer cells and may be used to develop a miRNA-based therapeutic strategy against pancreatic cancer.
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Orthogonally engineering matrix topography and rigidity to regulate multicellular morphology.
Adv. Mater. Weinheim
PUBLISHED: 06-04-2014
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Programmable polymer substrates, which mimic the variable extracellular matrices in living systems, are used to regulate multicellular morphology, via orthogonally modulating the matrix topography and elasticity. The multicellular morphology is dependent on the competition between cell-matrix adhesion and cell-cell adhesion. Decreasing the cell-matrix adhesion provokes cytoskeleton reorganization, inhibits lamellipodial crawling, and thus enhances the leakiness of multicellular morphology.
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Formation and characterization of light-responsive TEMPO-oxidized konjac glucomannan microspheres.
Biomacromolecules
PUBLISHED: 05-28-2014
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A light-responsive delivery system has been developed. It consists of gelly microspheres made of TEMPO-oxidized Konjac glucomannan (OKGM) polymers where the carboxyl (COO(-)) groups are cross-linked via ferric ions (Fe(3+)) and in which functional ingredients may be incorporated. By irradiation with (simulated) sunlight, the microspheres degrade, thereby releasing the encapsulated component(s). The degree of oxidation (DO) of the OKGM polymers could be well-controlled between 15 and 80%, as confirmed by proton titrations and FT-IR spectroscopy. OKGM of DO 80% was selected to prepare the microspheres because the high COO(-) content leads to a high density of cross-links, yielding a strong gel. The electrokinetic potential of the OKGM particles increases with increasing pH and decreasing salt concentration. Mössbauer and FT-IR spectroscopy revealed that the cross-links are formed through two modes of COO(-)-Fe(3+) coordination, that is, 68.4% by bridging and 31.6% by unidentate binding. Thus, the unique properties of the OKGM microspheres make them potentially applicable as light-controlled biocompatible delivery systems.
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Quantitative assessment of the diagnostic role of MUC1 in pancreatic ductal adenocarcinoma.
Tumour Biol.
PUBLISHED: 05-13-2014
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Pancreatic ductal adenocarcinoma has the worst prognosis of any gastrointestinal cancer, with the mortality approaching the incidence. Early detection is crucial for improving patient prognosis. We therefore performed a meta-analysis to assess the diagnostic performance of MUC1 for pancreatic ductal adenocarcinoma (PDAC). A comprehensive search was performed to retrieve relevant studies on detecting immunohistochemical expression of MUC1 in the diagnosis of PDAC. Data on accuracy of included studies were extracted for further heterogeneity exploring, statistical pooling, and SROC (summary receiver operating characteristics) analyzing using the Meta-DiSc 1.4 and STATA 12.0 software. Seventeen studies were se1ected with 1,363 patients involved. The heterogeneity (except for threshold effect) was found in these studies. The pooled sensitivity and specificity were 0.83 (95 % confidence interval (CI), 0.81-0.86) and 0.63 (95 % CI, 0.59-0.66), respectively. The pooled positive likelihood ratio (PLR) and negative likelihood ratio (NLR) were 3.02 (95 % CI, 1.95-4.70) and 0.21 (95 % CI, 0.13-0.32), respectively. The pooled diagnostic odds ratio (DOR) was 20.44 (95 % CI, 9.53-43.85). The area under of SROC curve was 0.8879 and the Q index was 0.8185. This meta-analysis indicates that MUC1 assay plays an important role in the diagnosis of PDAC.
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Mechanical force-driven growth of elongated bending TiO2 -based nanotubular materials for ultrafast rechargeable lithium ion batteries.
Adv. Mater. Weinheim
PUBLISHED: 05-04-2014
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A stirring hydrothermal process that enables the formation of elongated bending TiO2 -based nanotubes is presented. By making use of its bending nature, the elongated TiO2 (B) nanotubular crosslinked-network anode electrode can cycle over 10 000 times in half cells while retaining a relatively high capacity (114 mA h g(-1)) at an ultra-high rate of 25 C (8.4 A g(-1)).
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Novel action and mechanism of auranofin in inhibition of vascular endothelial growth factor receptor-3-dependent lymphangiogenesis.
Anticancer Agents Med Chem
PUBLISHED: 05-03-2014
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Auranofin is a gold compound initially developed for the treatment of rheumatoid arthritis. Recent data suggest that auranofin has promise in the treatment of other inflammatory and proliferative diseases. However, the mechanisms of action of auranofin have not been well defined. In the present study, we identify vascular endothelial growth factor receptor-3 (VEGFR3), an endothelial cell (EC) surface receptor essential for angiogiogenesis and lymphangiogenesis, as a novel target of auranofin. In both primary EC and EC cell lines, auranofin induces downregulation of VEGFR3 in a dose-dependent manner. Auranofin at high doses (?1 µM) decreases cellular survival protein thioredoxin reductase (TrxR2), TrxR2-dependent Trx2 and transcription factor NF-?B whereas increases stress signaling p38MAPK, leading to EC apoptosis. However, auranofin at low doses (?0.5 µM) specifically induces downregulation of VEGFR3 and VEGFR3-mediated EC proliferation and migration, two critical steps required for in vivo lymphangiogenesis. Mechanistically, we show that auranofin-induced VEGFR3 downregulation is blocked by antioxidant N-acetyl-L-cysteine (NAC) and lysosome inhibitor chloroquine, but is promoted by proteasomal inhibitor MG132. These results suggest that auranofin induces VEGFR3 degradation through a lysosome-dependent pathway. Auranofin may be a potent therapeutic agent for the treatment of lymphangiogenesis-dependent diseases such as lymphedema and cancer metastasis.
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Microstructured graphene arrays for highly sensitive flexible tactile sensors.
Small
PUBLISHED: 05-02-2014
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A highly sensitive tactile sensor is devised by applying microstructured graphene arrays as sensitive layers. The combination of graphene and anisotropic microstructures endows this sensor with an ultra-high sensitivity of -5.53 kPa(-1) , an ultra-fast response time of only 0.2 ms, as well as good reliability, rendering it promising for the application of tactile sensing in artificial skin and human-machine interface.
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Eye-centered visual receptive fields in the ventral intraparietal area.
J. Neurophysiol.
PUBLISHED: 04-30-2014
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The ventral intraparietal area (VIP) processes multisensory visual, vestibular, tactile, and auditory signals in diverse reference frames. We recently reported that visual heading signals in VIP are represented in an approximately eye-centered reference frame when measured using large-field optic flow stimuli. No VIP neuron was found to have head-centered visual heading tuning, and only a small proportion of cells had reference frames that were intermediate between eye- and head-centered. In contrast, previous studies using moving bar stimuli have reported that visual receptive fields (RFs) in VIP are head-centered for a substantial proportion of neurons. To examine whether these differences in previous findings might be due to the neuronal property examined (heading tuning vs. RF measurements) or the type of visual stimulus used (full-field optic flow vs. a single moving bar), we have quantitatively mapped visual RFs of VIP neurons using a large-field, multipatch, random-dot motion stimulus. By varying eye position relative to the head, we tested whether visual RFs in VIP are represented in head- or eye-centered reference frames. We found that the vast majority of VIP neurons have eye-centered RFs with only a single neuron classified as head-centered and a small minority classified as intermediate between eye- and head-centered. Our findings suggest that the spatial reference frames of visual responses in VIP may depend on the visual stimulation conditions used to measure RFs and might also be influenced by how attention is allocated during stimulus presentation.
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Quantitative assessment of the diagnostic role of human telomerase activity from pancreatic juice in pancreatic cancer.
Tumour Biol.
PUBLISHED: 04-23-2014
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Many studies have shown that human telomerase activity could play potential role as a diagnostic biomarker of pancreatic cancer (PaC). The aim of this meta-analysis is to summarize the clinical value of human telomerase activity in the diagnosis of PaC. Eligible studies from PubMed, Embase, the Cochrane Library, Web of Science, Ovid, Sci Verse, Science Direct, Scopus, BioMed Central, Biosis previews, Chinese Biomedical Literature Database (CBM), Chinese National Knowledge Infrastructure (CNKI), Technology of Chongqing (VIP), and Wan Fang databases were searched concerning the diagnostic value of human telomerase activity in PaC without language restriction. The quality of each study was scored with the Quality Assessment of Diagnostic Accuracy Studies (QUADAS). Sensitivity, specificity, positive and negative likelihood ratios (PLR and NLR, respectively), and diagnostic odds ratio (DOR) for human telomerase activity in the diagnosis of PaC were pooled. Summary receiver operating characteristic (SROC) curve analysis and the area under the curve (AUC) were used to estimate the overall test performance. Evidence of heterogeneity was evaluated using the Chi-square and I (2) test. Meta-Disc 1.4 and Stata 12.0 software were used to analyze the data. Nine studies with a total 186 PaC patients and 132 control individuals were included in this meta-analysis. All of the included studies are of high quality (QUADAS score ?10). The summary estimate was 0.83 (95 % confidence interval (CI), 95 % CI?=?0.77-0.88) for sensitivity and 0.72 (95 % CI?=?0.64-0.79) for specificity. The positive likelihood (PLR), negative likelihood (NLR), and diagnostic odds (DOR) ratios were 3 (95 % CI?=?1.67-5.41), 0.25 (95 % CI?=?0.13-0.46), and 3 (95 % CI?=?4.91-43.23), respectively. The area under the summary ROC curve (AUC) and Q* index for the diagnosis of PaC were 0.88 and 0.81, respectively. Our study demonstrates that telomerase could be a useful tumor marker for PaC diagnosis. Although more studies are needed to highlight the theoretical strengths, these results will provide theoretical basis for bringing telomerase activity detection into PaC screening plan.
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Cartilage status in knees with recurrent patellar instability using magnetic resonance imaging T2 relaxation time value.
Knee Surg Sports Traumatol Arthrosc
PUBLISHED: 04-22-2014
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The purpose of the study was to analyse the patellar status in patients with recurrent patellar instability and in healthy controls using magnetic resonance imaging (MRI).
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Deposition of luminescent Y2O3:Eu3+ on ferromagnetic mesoporous CoFe2O4@mSiO2 nanocomposites.
Phys Chem Chem Phys
PUBLISHED: 04-18-2014
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Luminescent Y2O3:Eu(3+) particles have been deposited on the surface of ferromagnetic mesoporous CoFe2O4@mSiO2 nanoparticles by a co-precipitation method, obtaining multifunctional CoFe2O4@mSiO2@Y2O3:Eu(3+) nanocomposites. XRD, SEM, TEM, EDX, XPS, N2-adsorption-desorption, FT-IR, VSM and PL were used to characterized the samples. The results reveal that the nanocomposites display typical mesoporous characteristics with high surface areas (BET), large pore volumes and core-shell structures. The composites show ferromagnetic properties and red luminescence from the (5)D0-(7)F2 transition at 610 nm. The size and the magnetic and luminescence properties of the composites could be tuned by systematically varying the experimental parameters, such as the annealing temperature, the mass ratio of CoFe2O4@mSiO2 to Y2O3:Eu(3+), and the volume of TEOS. A possible quenching mechanism of the luminescent Y2O3:Eu(3+) by the ferromagnetic CoFe2O4 is proposed. The high BET and large pore volume may give the composite potential application in controlled drug release.
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A new algorithm for calculating optimal viewing angles in coronary angiography based on 4-D cardiac computed tomography.
J Xray Sci Technol
PUBLISHED: 04-05-2014
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Coronary stenosis is the main cause of the coronary heart disease (CHD). However, coronary arteriography (CAG), which is considered as the 'gold standard' of determining the location and severity of CHD, hardly acquires a satisfactory image for some lesions by traditional viewing angles.
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Nanostructured graphene composite papers for highly flexible and foldable supercapacitors.
Adv. Mater. Weinheim
PUBLISHED: 04-03-2014
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Reduced graphene oxide (rGO) and polyaniline (PANI) assemble onto the surface of cellulose fibers (CFs) and into the pores of CF paper, to form a hierarchical nanostructured PANI-rGO/CF composite paper. Based on these composite papers, flexible and foldable all-solid-state supercapacitors are achieved.
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Sparse CT reconstruction based on multi-direction anisotropic total variation (MDATV).
Biomed Eng Online
PUBLISHED: 03-31-2014
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The sparse CT (Computed Tomography), inspired by compressed sensing, means to introduce a prior information of image sparsity into CT reconstruction to reduce the input projections so as to reduce the potential threat of incremental X-ray dose to patients' health. Recently, many remarkable works were concentrated on the sparse CT reconstruction from sparse (limited-angle or few-view style) projections. In this paper we would like to incorporate more prior information into the sparse CT reconstruction for improvement of performance. It is known decades ago that the given projection directions can provide information about the directions of edges in the restored CT image. ATV (Anisotropic Total Variation), a TV (Total Variation) norm based regularization, could use the prior information of image sparsity and edge direction simultaneously. But ATV can only represent the edge information in few directions and lose much prior information of image edges in other directions.
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Do Residents Receive the Same OR Guidance as Surgeons Report? Difference Between Residents' and Surgeons' Perceptions of OR Guidance.
J Surg Educ
PUBLISHED: 03-26-2014
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Operating room (OR) guidance is important for surgical residents' performance and, ultimately, for the development of independence and autonomy. This study explores the differences in surgical residents' and attending surgeons' perceptions of OR guidance in prerecorded surgical cases.
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Optoelectronics of organic nanofibers formed by co-assembly of porphyrin and perylenediimide.
Small
PUBLISHED: 03-24-2014
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Organic nanofibers are formed by simple ionic co-assembly of positively charged porphyrin (electron donor) and negatively charged perylenediimide (electron acceptor) derivatives in aqueous solution. Two kinds of electron transfer routes between electron donor and electron acceptor under light excitation in nanofibers are confirmed by DFT calculations and experimental data.
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The Measured Effect of Delay in Completing Operative Performance Ratings on Clarity and Detail of Ratings Assigned.
J Surg Educ
PUBLISHED: 03-13-2014
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Operative performance ratings (OPRs) need adequate clarity and detail to support self-directed learning and valid progress decisions. This study was designed to determine (1) the elapsed time between observing operative performances and completing performance ratings under field conditions and (2) the effect of increased elapsed time on rating clarity and detail.
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Optical reading of contaminants in aqueous media based on gold nanoparticles.
Small
PUBLISHED: 02-27-2014
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With increasing trends of global population growth, urbanization, pollution over-exploitation, and climate change, the safe water supply has become a global issue and is threatening our society in terms of sustainable development. Therefore, there is a growing need for a water-monitoring platform with the capability of rapidness, specificity, low-cost, and robustness. This review summarizes the recent developments in the design and application of gold nanoparticles (AuNPs) based optical assays to detect contaminants in aqueous media with a high performance. First, a brief discussion on the correlation between the optical reading strategy and the optical properties of AuNPs is presented. Then, we summarize the principle behind AuNP-based optical assays to detect different contaminants, such as toxic metal ion, anion, and pesticides, according to different optical reading strategies: colorimetry, scattering, and fluorescence. Finally, the comparison of these assays and the outlook of AuNP-based optical detection are discussed.
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Deferoxamine promotes MDA-MB-231 cell migration and invasion through increased ROS-dependent HIF-1? accumulation.
Cell. Physiol. Biochem.
PUBLISHED: 02-24-2014
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Deferoxamine (DFO), an iron chelator, has been reported to induce hypoxia-inducible factor-1? (HIF-1?) expression. HIF-1? plays a critical role in promoting tumor metastasis. However, the molecular mechanisms underlying induction of HIF-1? in breast cancer cells remain unknown. Our aim was to ascertain whether DFO enhanced cancer metastasis in MDA-MB-231 cells.
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The effects of prenatal exposure to low-level cadmium, lead and selenium on birth outcomes.
Chemosphere
PUBLISHED: 02-21-2014
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To evaluate the current maternal and fetal exposure to cadmium (Cd), lead (Pb) and selenium (Se), and their potential effect on newborn birth outcomes, a cross-sectional study involving an assessment of the levels of these three metals in maternal blood, urine and umbilical cord blood was conducted in 209 pregnant women living in Eastern China. The maternal blood, urine and cord blood samples were collected and measured with inductively coupled plasma mass spectrometry (ICP-MS). The maternal blood concentrations of Cd, Pb and Se (the geometric means (GMs) were 0.48, 39.50 and 143.53 ?g L(-1)) were significantly higher than and correlated with those in the cord blood (GM: 0.09, 31.62 and 124.61 ?g L(-1)). In the urine samples, the GMs for Cd, Pb and Se were 0.13, 0.48, and 4.78 ?g L(-1), respectively. Passive smoking was found to positively correlate with urine Cd (r=0.16) and negatively correlate with urine Se (r=-0.29). The maternal blood Se level was negatively associated with the cord Cd levels (r=-0.41). The blood Cd concentration in the mother could significantly affect the newborn birth weight (r=-0.22), but it was not correlated with birth height. We identified cord Se as a new factor which significantly correlated with birth weight. In conclusion, maternal Cd, Pb, Se exposure correlated with their umbilical cord concentration, and maternal Cd exposure might affect the newborn birth weight. Increasing the Se intake might reduce the cord blood Cd concentration and promote the fetal growth.
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Programmable photo-electrochemical hydrogen evolution based on multi-segmented CdS-Au nanorod arrays.
Adv. Mater. Weinheim
PUBLISHED: 01-23-2014
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Programmable photocatalysts for hydrogen evolution have been fabricated based on multi-segmented CdS-Au nanorod arrays, which exhibited high-efficiency and programmability in hydrogen evolution as the photoanodes in the photoelectrochemical cell. Multiple different components each possess unique physical and chemical properties that provide these cascade nanostructures with multiformity, programmability, and adaptability. These advantages allow these nanostructures as promising candidates for high efficient harvesting and conversion of solar energy.
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A synergistic capture strategy for enhanced detection and elimination of bacteria.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 01-23-2014
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Despite the advanced detection and sterilization techniques available today, the sensitive diagnosis and complete elimination of bacterial infections remain a significant challenge. A strategy is reported for efficient bacterial capture (ca. 90%) based on the synergistic effect of the nanotopography and surface chemistry of the substrate on bacterial attachment and adhesion. The outstanding bacterial-capture capability of the functionalized nanostructured substrate enables rapid and highly sensitive bacterial detection down to trace concentrations of pathogenic bacteria (10?colony-forming units mL(-1)). In addition, this synergistic biocapture substrate can be used for efficient bacterial elimination and shows great potential for clinical antibacterial applications.
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Mesenchymal stem cells use IDO to regulate immunity in tumor microenvironment.
Cancer Res.
PUBLISHED: 01-22-2014
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Mesenchymal stem cells (MSC) are present in most, if not all, tissues and are believed to contribute to tissue regeneration and the tissue immune microenvironment. Murine MSCs exert immunosuppressive effects through production of inducible nitric oxide synthase (iNOS), whereas human MSCs use indoleamine 2,3-dioxygenase (IDO). Thus, studies of MSC-mediated immunomodulation in mice may not be informative in the setting of human disease, although this critical difference has been mainly ignored. To address this issue, we established a novel humanized system to model human MSCs, using murine iNOS(-/-) MSCs that constitutively or inducibly express an ectopic human IDO gene. In this system, inducible IDO expression is driven by a mouse iNOS promoter that can be activated by inflammatory cytokine stimulation in a similar fashion as the human IDO promoter. These IDO-expressing humanized MSCs (MSC-IDO) were capable of suppressing T-lymphocyte proliferation in vitro. In melanoma and lymphoma tumor models, MSC-IDO promoted tumor growth in vivo, an effect that was reversed by the IDO inhibitor 1-methyl-tryptophan. We found that MSC-IDO dramatically reduced both tumor-infiltrating CD8(+) T cells and B cells. Our findings offer an important new line of evidence that interventional targeting of IDO activity could be used to restore tumor immunity in humans, by relieving IDO-mediated immune suppression of MSCs in the tumor microenvironment as well as in tumor cells themselves.
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An adaptive 6-DOF tracking method by hybrid sensing for ultrasonic endoscopes.
Sensors (Basel)
PUBLISHED: 01-17-2014
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In this paper, a novel hybrid sensing method for tracking an ultrasonic endoscope within the gastrointestinal (GI) track is presented, and the prototype of the tracking system is also developed. We implement 6-DOF localization by sensing integration and information fusion. On the hardware level, a tri-axis gyroscope and accelerometer, and a magnetic angular rate and gravity (MARG) sensor array are attached at the end of endoscopes, and three symmetric cylindrical coils are placed around patients' abdomens. On the algorithm level, an adaptive fast quaternion convergence (AFQC) algorithm is introduced to determine the orientation by fusing inertial/magnetic measurements, in which the effects of magnetic disturbance and acceleration are estimated to gain an adaptive convergence output. A simplified electro-magnetic tracking (SEMT) algorithm for dimensional position is also implemented, which can easily integrate the AFQC's results and magnetic measurements. Subsequently, the average position error is under 0.3 cm by reasonable setting, and the average orientation error is 1° without noise. If magnetic disturbance or acceleration exists, the average orientation error can be controlled to less than 3.5°.
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Structural diversity of bulky graphene materials.
Small
PUBLISHED: 01-17-2014
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The unique two-dimensional (2D) structure and chemical properties of graphene and its derivatives make it a distinctive nanoscale building block for constructing novel bulky architectures with different dimensions, such as 1D fibers, 2D films and 3D architectures. These bulky graphene materials, depending on the manner in which graphene sheets are assembled, show a variety of fascinating features that cannot be achieved from individual graphene sheet or conventional materials. Thus, over the past several years, considerable effort has been expended in fabricating various structures of bulky graphene materials and developing their corresponding applications. Here, we present a broad and comprehensive overview of the recent developments in expanding the structural diversity of bulky graphene materials and their applications in energy storage and conversion, composites, environmental remediation, etc. Finally, prospects and further developments in this exciting field of bulky graphene materials are also suggested.
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Porous graphene materials for water remediation.
Small
PUBLISHED: 01-16-2014
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Water remediation has been a critical issue over the past decades due to the expansion of wastewater discharge to the environment. Currently, a variety of functional materials have been successfully prepared for water remediation applications. Among them, graphene is an attractive candidate due to its high specific surface area, tunable surface behavior, and high strength. This Concept paper summarizes the design strategy of porous graphene materials and their applications in water remediation, such as the cleanup of oil, removal of heavy metal ions, and elimination of water soluble organic contaminants. The progress made so far will guide further development in structure design strategy of porous materials based on graphene and exploration of such materials in environmental remediation.
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Quantitative assessment of the association between L769L and S836S polymorphisms at RET gene and medullary thyroid carcinoma risk.
Tumour Biol.
PUBLISHED: 01-12-2014
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RET single nucleotide polymorphisms (SNPs) have been implicated in the pathogenesis and progression of medullary thyroid carcinoma (MTC). Epidemiologic studies have evaluated the association between RET L769L and S836S polymorphisms and predisposition to MTC. However, the results were inconclusive. A literature search was performed using the PubMed database for relevant studies published through October 31, 2013. A total of 13 eligible studies were selected for this meta-analysis, including 1,117 cases and 1,916 controls for L769L and 1,230 cases and 2,246 controls for S836S. The carrier frequency of the variant alleles was 26.3 % in patients with MTC and 24.6 % in controls for L769L polymorphism, and 6.6 % in patients with MTC and 5.0 % in controls for S836S polymorphism. In our pooled analysis of all these studies, the results of our meta-analysis suggested that the RET L769L variant was not significantly associated with an elevated MTC risk (odds ratio (OR) 1.06, 95 % confidence interval (CI) 0.94-1.19). And there was no evidence for the association between the S836S variant and MTC risk (OR 1.20, 95 % CI 0.97-1.49). Moreover, no significant differences were found when considering patients or controls heterozygous or homozygous for RET L769L and S836S polymorphisms. In conclusion, this meta-analysis suggests that RET L769L and S836S polymorphisms may not be associated with MTC development.
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AIP1 mediates vascular endothelial cell growth factor receptor-3-dependent angiogenic and lymphangiogenic responses.
Arterioscler. Thromb. Vasc. Biol.
PUBLISHED: 01-09-2014
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To investigate the novel function of ASK1-interacting protein-1 (AIP1) in vascular endothelial cell growth factor receptor (VEGFR)-3 signaling, and VEGFR-3-dependent angiogenesis and lymphangiogenesis.
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Orthogonally modulated molecular transport junctions for resettable electronic logic gates.
Nat Commun
PUBLISHED: 01-08-2014
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Individual molecules have been demonstrated to exhibit promising applications as functional components in the fabrication of computing nanocircuits. Based on their advantage in chemical tailorability, many molecular devices with advanced electronic functions have been developed, which can be further modulated by the introduction of external stimuli. Here, orthogonally modulated molecular transport junctions are achieved via chemically fabricated nanogaps functionalized with dithienylethene units bearing organometallic ruthenium fragments. The addressable and stepwise control of molecular isomerization can be repeatedly and reversibly completed with a judicious use of the orthogonal optical and electrochemical stimuli to reach the controllable switching of conductivity between two distinct states. These photo-/electro-cooperative nanodevices can be applied as resettable electronic logic gates for Boolean computing, such as a two-input OR and a three-input AND-OR. The proof-of-concept of such logic gates demonstrates the possibility to develop multifunctional molecular devices by rational chemical design.
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Pyrethroid and their metabolite, 3-phenoxybenzoic acid showed similar (anti)estrogenic activity in human and rat estrogen receptor ?-mediated reporter gene assays.
Environ. Toxicol. Pharmacol.
PUBLISHED: 01-07-2014
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Pyrethroids are commonly used as pesticides which are suspected as endocrine disruptors in many studies; however, still we do not know their effects on different species. To compare their effects on human estrogen receptor (hER?) and rat estrogen receptor (rER?), we developed a hER? and rER? mediated luciferase reporter assay to investigate the (anti)estrogenic activities of three frequently used pyrethroids (fenvalerate, cypermethrin, permethrin) and their metabolite 3-phenoxybenzoic acid (3-PBA). All three pyrethroids significantly induced expression of the luciferase, while none of them were antagonistic to 1 nM E? mediated induction. Interestingly, 3-PBA, showed antagonist activity by decreasing the effect of 1 nM E? to 55.12% in hER? assay and to 45.12% in rER? assay. Our results firstly demonstrated that pyrethroids and 3-PBA showed similar response in the hER? and rER? mediated reporter gene assay, which indicated that data derived from reporter gene assay or other receptor mediated assay systems with rat ER system might be used to predict to estrogenic or anti-estrogenic effects to human systems.
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Agreement of try-in pastes and the corresponding luting composites on the final color of ceramic veneers.
J Prosthodont
PUBLISHED: 01-06-2014
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The aims of this study were to evaluate the influence of luting composites on the final color of ceramic veneers and to investigate the color matching of try-in pastes to the corresponding luting composites.
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Analysis of Five Earthy-Musty Odorants in Environmental Water by HS-SPME/GC-MS.
Int J Anal Chem
PUBLISHED: 01-02-2014
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The pressing issue of earthy and musty odor compounds in natural waters, which can affect the organoleptic properties of drinking water, makes it a public health concern. A simple and sensitive method for simultaneous analysis of five odorants in environmental water was developed by headspace solid-phase microextraction (HS-SPME) coupled to chromatography-mass spectrometry (GC-MS), including geosmin (GSM) and 2-methylisoborneol (2-MIB), as well as dimethyl trisulfide (DMTS), ? -cyclocitral, and ? -ionone. Based on the simple modification of original magnetic stirrer purchased from CORNING (USA), the five target compounds can be separated within 23?min, and the calibration curves show good linearity with a correlation coefficient above 0.999 (levels?=?5). The limits of detection (LOD) are all below 1.3?ng?L(-1), and the relative standard deviation (%RSD) is between 4.4% and 9.9% (n = 7) and recoveries of the analytes from water samples are between 86.2% and 112.3%. In addition, the storage time experiment indicated that the concentrations did not change significantly for GSM and 2-MIB if they were stored in canonical environment. In conclusion, the method in this study could be applied for monitoring these five odorants in natural waters.
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A simple method suitable to study de novo root organogenesis.
Front Plant Sci
PUBLISHED: 01-01-2014
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De novo root organogenesis is the process in which adventitious roots regenerate from detached or wounded plant tissues or organs. In tissue culture, appropriate types and concentrations of plant hormones in the medium are critical for inducing adventitious roots. However, in natural conditions, regeneration from detached organs is likely to rely on endogenous hormones. To investigate the actions of endogenous hormones and the molecular mechanisms guiding de novo root organogenesis, we developed a simple method to imitate natural conditions for adventitious root formation by culturing Arabidopsis thaliana leaf explants on B5 medium without additive hormones. Here we show that the ability of the leaf explants to regenerate roots depends on the age of the leaf and on certain nutrients in the medium. Based on these observations, we provide examples of how this method can be used in different situations, and how it can be optimized. This simple method could be used to investigate the effects of various physiological and molecular changes on the regeneration of adventitious roots. It is also useful for tracing cell lineage during the regeneration process by differential interference contrast observation of ?-glucuronidase staining, and by live imaging of proteins labeled with fluorescent tags.
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A catechol biosensor based on electrospun carbon nanofibers.
Beilstein J Nanotechnol
PUBLISHED: 01-01-2014
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Carbon nanofibers (CNFs) were prepared by combining electrospinning with a high-temperature carbonization technique. And a polyphenol biosensor was fabricated by blending the obtained CNFs with laccase and Nafion. Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR) and field emission scanning electron microscope (FE-SEM) were, respectively, employed to investigate the structures and morphologies of the CNFs and of the mixtures. Cyclic voltammetry and chronoamperometry were employed to study the electrocatalysis of the catechol biosensor. The results indicated that the sensitivity of the biosensor was 41 µA·mM(-1), the detection limit was 0.63 µM, the linear range was 1-1310 µM and the response time was within 2 seconds, which excelled most other laccase-based biosensor reported. Furthermore, the biosensor showed good repeatability, reproducibility, stability and tolerance to interferences. This novel biosensor also demonstrated its promising application in detecting catechol in real water samples.
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Nanoparticles Strengthen Intracellular Tension and Retard Cellular Migration.
Nano Lett.
PUBLISHED: 12-18-2013
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Nanoparticles can have profound effects on cell biology. Here, we show that after TiO2, SiO2, and hydroxyapatite nanoparticles treatment, TR146 epithelial cell sheet displayed slower migration. Cells after exposure to the nanoparticles showed increased cell contractility with significantly impaired wound healing capability however without any apparent cytotoxicity. We showed the mechanism is through nanoparticle-mediated massive disruption of the intracellular microtubule assembly, thereby triggering a positive feedback that promoted stronger substrate adhesions thus leading to limited cell motility.
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Eye-centered representation of optic flow tuning in the ventral intraparietal area.
J. Neurosci.
PUBLISHED: 11-22-2013
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Reference frames are important for understanding sensory processing in the cortex. Previous work showed that vestibular heading signals in the ventral intraparietal area (VIP) are represented in body-centered coordinates. In contrast, vestibular heading tuning in the medial superior temporal area (MSTd) is approximately head centered. We considered the hypothesis that visual heading signals (from optic flow) in VIP might also be transformed into a body-centered representation, unlike visual heading tuning in MSTd, which is approximately eye centered. We distinguished among eye-centered, head-centered, and body-centered spatial reference frames by systematically varying both eye and head positions while rhesus monkeys viewed optic flow stimuli depicting various headings. We found that heading tuning of VIP neurons based on optic flow generally shifted with eye position, indicating an eye-centered spatial reference frame. This is similar to the representation of visual heading signals in MSTd, but contrasts sharply with the body-centered representation of vestibular heading signals in VIP. These findings demonstrate a clear dissociation between the spatial reference frames of visual and vestibular signals in VIP, and emphasize that frames of reference for neurons in parietal cortex can depend on the type of sensory stimulation.
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Bio-inspired antireflective hetero-nanojunctions with enhanced photoactivity.
Nanoscale
PUBLISHED: 10-29-2013
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A bio-inspired antireflective hetero-nanojunction structure has been fabricated by the hydrothermal growth of ZnO nanorods on silicon micro-pyramids. It has been shown that this structure suppresses light reflection more effectively resulting in a high photocurrent response and good charge separation simultaneously. The strategy provides a means to enhance solar energy conversion.
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Heterogeneous visible light photocatalysis for selective organic transformations.
Chem Soc Rev
PUBLISHED: 10-25-2013
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The future development of chemistry entails environmentally friendly and energy sustainable alternatives for organic transformations. Visible light photocatalysis can address these challenges, as reflected by recent intensive scientific endeavours to this end. This review covers state-of-the-art accomplishments in visible-light-induced selective organic transformations by heterogeneous photocatalysis. The discussion comprises three sections based on the photocatalyst type: metal oxides such as TiO2, Nb2O5 and ZnO; plasmonic photocatalysts like nanostructured Au, Ag or Cu supported on metal oxides; and polymeric graphitic carbon nitride. Finally, recent strides in bridging the gap between photocatalysis and other areas of catalysis will be highlighted with the aim of overcoming the existing limitations of photocatalysis by developing more creative synthetic methodologies.
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Influence of methylenetetrahydrofolate reductase C677T polymorphism on the risk of lung cancer and the clinical response to platinum-based chemotherapy for advanced non-small cell lung cancer: an updated meta-analysis.
Yonsei Med. J.
PUBLISHED: 10-22-2013
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Methylenetetrahydrofolate reductase (MTHFR) has been implicated in lung cancer risk and response to platinum-based chemotherapy in advanced non-small cell lung cancer (NSCLC). However, the results are controversial. We performed meta-analysis to investigate the effect of MTHFR C677T polymorphism on lung cancer risk and response to platinum-based chemotherapy in advanced NSCLC.
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In situ assembly of monodisperse, multifunctional silica microspheres embedded with magnetic and fluorescent nanoparticles and their application in adsorption of methylene blue.
Phys Chem Chem Phys
PUBLISHED: 10-02-2013
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Many efforts have been devoted towards the fabrication of multifunctional (mesoporous, magnetic and fluorescent) nanocomposites due to their growing applications as adsorbents, catalysts, and biomedical application, etc. Novel, flower-structured multifunctional Fe3O4/YVO4:Eu(3+)@SiO2 microspheres were successfully synthesized through a simple self-assembled process. The as-obtained products were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), N2 adsorption-desorption, photoluminescence (PL) spectroscopy and using a vibrating sample magnetometer (VSM). The results reveal that the novel composites exhibit typical mesoporous structure, narrow size distribution, good monodispersity, excellent luminescent properties and superparamagnetic features. The effects of magnetic field on the luminescent intensity of multifunctional composites have been discussed in our manuscript. Furthermore, the adsorption experiments indicate that the resulting multifunctional composites are powerful adsorbents for the removal of methylene blue from water with a maximum adsorption efficiency of 98%. It is envisioned that multifunctional composites with high surface area are of particular interest for adsorption of pollutants, separation, and water purification.
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The role of vascular epithelial growth factor receptor-tyrosine kinase inhibitors in the treatment of advanced breast cancer: a meta-analysis of 12 randomized controlled trials.
Curr Med Res Opin
PUBLISHED: 09-23-2013
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Abstract Aim: To perform a systematic review and meta-analysis of randomized controlled trials to determine the efficacy and toxicity of approved vascular epithelial growth factor receptor-tyrosine kinase inhibitors (VEGFR-TKIs) in advanced breast cancer. Methods: A comprehensive literature search for studies published up to August 2013 was performed. The endpoints were overall survival (OS), progression-free survival (PFS), overall response rate (ORR) and grade 3 or 4 adverse event (AEs). The pooled hazard ratio (HR) or relative risk (RR), and 95% confidence intervals (CI) were calculated employing fixed- or random-effects models depending on the heterogeneity of the included trials. Results: Twelve randomized controlled trials involved 3256 patients were ultimately identified. The intention to treatment (ITT) analysis demonstrated that VEGFR-TKI therapy significantly improved ORR (RR 1.14, 95% CI: 1.03-1.28, p?=?0.016), but it did not translate into benefits in PFS (HR 0.99, 95% CI: 0.81-1.22, p?=?0.93) and OS (HR 1.11, 95% CI 0.99-1.24, p?=?0.084) when compared to non-VEGFR-TKI therapy. Additionally, a higher incidence of grade 3 or 4 anemia, neutropenia, thrombocytopenia, diarrhea, hand-foot syndrome and fatigue was observed in VEGFR-TKI-based therapy. Conclusions: The VEGFR-TKI-based therapy offered a significant improvement in ORR in patients with advanced breast cancer but did not benefit PFS and OS. With present available data from randomized clinical trials, we were still unable to clearly set the role of VEGFR-TKIs in the treatment of metastatic breast cancer (MBC).
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Acoustic radiation force impulse (ARFI) imaging of preliminary mucosa associated lymphoid tissue (MALT) lymphoma in the breast: a case report.
Quant Imaging Med Surg
PUBLISHED: 09-15-2013
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Primary lymphoma is a rare neoplasm in the breast accounting for between 0.04% and 0.5% of all malignant mammary tumors. The majority of cases lack typical features of breast malignancy or lymphoma, and likely to be misdiagnosed during daily clinical practice. In this report we describe a case of primary breast lymphoma assessed with acoustic radiation force impulse (ARFI) technology.
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Diverse spatial reference frames of vestibular signals in parietal cortex.
Neuron
PUBLISHED: 08-25-2013
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Reference frames are important for understanding how sensory cues from different modalities are coordinated to guide behavior, and the parietal cortex is critical to these functions. We compare reference frames of vestibular self-motion signals in the ventral intraparietal area (VIP), parietoinsular vestibular cortex (PIVC), and dorsal medial superior temporal area (MSTd). Vestibular heading tuning in VIP is invariant to changes in both eye and head positions, indicating a body (or world)-centered reference frame. Vestibular signals in PIVC have reference frames that are intermediate between head and body centered. In contrast, MSTd neurons show reference frames between head and eye centered but not body centered. Eye and head position gain fields were strongest in MSTd and weakest in PIVC. Our findings reveal distinct spatial reference frames for representing vestibular signals and pose new challenges for understanding the respective roles of these areas in potentially diverse vestibular functions.
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Two-dimensional heterospectral correlation analysis of the redox-induced conformational transition in cytochrome c using surface-enhanced Raman and infrared absorption spectroscopies on a two-layer gold surface.
J Phys Chem B
PUBLISHED: 08-12-2013
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The heme protein cytochrome c adsorbed to a two-layer gold surface modified with a self-assembled monolayer of 2-mercaptoethanol was analyzed using a two-dimensional (2D) heterospectral correlation analysis that combined surface-enhanced infrared absorption spectroscopy (SEIRAS) and surface-enhanced Raman spectroscopy (SERS). Stepwise increasing electric potentials were applied to alter the redox state of the protein and to induce conformational changes within the protein backbone. We demonstrate herein that 2D heterospectral correlation analysis is a particularly suitable and useful technique for the study of heme-containing proteins as the two spectroscopies address different portions of the protein. Thus, by correlating SERS and SEIRAS data in a 2D plot, we can obtain a deeper understanding of the conformational changes occurring at the redox center and in the supporting protein backbone during the electron transfer process. The correlation analyses are complemented by molecular dynamics calculations to explore the intramolecular interactions.
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Clean unzipping by steam etching to synthesize graphene nanoribbons.
Nanotechnology
PUBLISHED: 07-18-2013
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A simple, clean method of steam etching carbon nanotubes is reported for the synthesis of graphene nanoribbons. The chemical mechanism of carbon nanotube unzipping is also discussed. As an anode catalyst, as-prepared graphene nanoribbons combined with Pt exhibit quite a high catalytic activity for ethanol electro-oxidation in fuel cells.
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Synergistic Modulation of Surface Interaction to Assemble Metal Nanoparticles into Two-Dimensional Arrays with Tunable Plasmonic Properties.
Small
PUBLISHED: 07-11-2013
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A simple strategy based on the synergistic modulation of inter-particle and substrate-particle interaction is applied for the large-scale fabrication of two-dimensional (2D) Au and Ag nanoparticle arrays. The surface charge of the substrate is used to redistribute the double layer electric charges on the particles and to modulate the inter-particle distance within the 2D nanoparticle arrays on the substrate. The resultant arrays, with a wide range of inter-particle distances, display tunable plasmonic properties. It can be foreseen that such 2D nanoparticle arrays possess potential applications as multiplexed colorimetric sensors, integrated devices and antennas. Herein, it is demonstrated that these arrays can be employed as wavelength-selective substrates for multiplexed acquisition of surface-enhanced Raman scattering (SERS) spectra. This simple one step process provides an attractive and low cost strategy to produce high quality and large area 2D ordered arrays with tunable properties.
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The role of intestinal mucosa injury induced by intra-abdominal hypertension in the development of abdominal compartment syndrome and multiple organ dysfunction syndrome.
Crit Care
PUBLISHED: 07-02-2013
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Abdominal distension is common in critical illness. There is a growing recognition that intra-abdominal hypertension (IAH) may complicate non-surgical critical illness as well as after abdominal surgery. However, the pathophysiological basis of the injury to the intestinal mucosal barrier and its influence on the onset of abdominal compartment syndrome (ACS) and multi-organ dysfunction syndrome (MODS) remain unclear. We measured intestinal microcirculatory blood flow (MBF) during periods of raised intra-abdominal pressure (IAP) and examined how this influenced intestinal permeability, systemic endotoxin release, and histopathological changes.
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Graphene Carrier for Magneto-Controllable Bioelectrocatalysis.
Small
PUBLISHED: 06-30-2013
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A magnetically driven fuel-free graphene carrier loaded with redox-active cargo-ferrocene as an electron mediator is fabricated for magneto-controllable bioelectrocatalysis. The activation and deactivation of redox-active cargos redox activity by magnetically driven positioning of the graphene carrier with loaded ferrocene near and away from the conductive support can be employed for magneto-switchable bioelectrocatalyzed oxidation of glucose by glucose oxidase between active and inactive electrocatalytic states, respectively.
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Orthogonal Design Study on Factors Affecting the Determination of Common Odors in Water Samples by Headspace Solid-Phase Microextraction Coupled to GC/MS.
J Anal Methods Chem
PUBLISHED: 05-30-2013
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Geosmin and 2-MIB are responsible for the majority of earthy and musty events related to the drinking water. These two odorants have extremely low odor threshold concentrations at ng?L(-1) level in the water, so a simple and sensitive method for the analysis of such trace levels was developed by headspace solid-phase microextraction coupled to gas chromatography/mass spectrometry. In this study, the orthogonal experiment design L32 (4(9)) was applied to arrange and optimize experimental conditions. The optimum was the following: temperatures of extraction and desorption, 65°C and 260°C, respectively; times of extraction and desorption, 30?min and 5?min, respectively; ionic strength, 25% (w/v); rotate-speed, 600?rpm; solution pH, 5.0. Under the optimized conditions, limits of detection (S/N = 3) were 0.04 and 0.13?ng?L(-1) for geosmin and 2-MIB, respectively. Calculated calibration curves gave high levels of linearity with a correlation coefficient value of 0.9999 for them. Finally, the proposed method was applied to water samples, which were previously analyzed and confirmed to be free of target analytes. Besides, the proposal method was applied to test environmental water samples. The RSDs were 2.75%~3.80% and 4.35%~7.6% for geosmin and 2-MIB, respectively, and the recoveries were 91%~107% and 91%~104% for geosmin and 2-MIB, respectively.
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Continuous growth and improved PL property of ZnO nanoarrays with assistance of polyethylenimine.
Nanoscale
PUBLISHED: 05-28-2013
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Recent studies show that polyethylenimine (PEI) benefits the hydrothermal growth of ZnO nanorod arrays due to its effect on chelating Zn(2+) ions and selectively absorbing on the crystal facets. In the present work, PEI is found to play more complex roles during the growth. The observation on the solution color and the UV-VIS and FTIR spectra demonstrate a Mannich reaction between HCHO and -NH2 groups of PEI during the hydrothermal procedure. -N=CH2 groups produced by the Mannich reaction contribute to the color change. The HMT decomposition is the controlling step for the whole growth and the decomposition rate depends on the hydrothermal temperature and the PEI addition amount. Increasing the PEI amount elevates the hydrothermal temperature to 130 °C and as a result the crystal quality is improved. A stepping heating process is designed to grow ultralong ZnO nanorod arrays by optimizing the solution composition. The rod length reaches to about 13 ?m by one growth circle. The mechanisms associated with PEI addition provide a novel route for synthesizing metal oxide nanomaterials, particularly those requiring the higher hydrothermal temperature.
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Effects and Safety of Allogenic Mesenchymal Stem Cells Intravenous Infusion in Active Ankylosing Spondylitis Patients Who Failed NSAIDs: A 20 Week Clinical Trial.
Cell Transplant
PUBLISHED: 05-22-2013
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Objective: To evaluate the feasibility, safety, and efficacy of intravenous infusion of allogenic mesenchymal stem cells (MSCs) in ankylosing spondylitis (AS) patients who are refractory to or could not tolerate the side effects of nonsteroidal anti-inflammatory drugs (NSAIDs). Method: AS patients enrolled in this study received 4 intravenous infusions (IVI) of MSCs on days 0,7,14, and 21. The percentage of ASAS20 responders (the primary endpoint) at the 4th week and the mean ASAS20 response duration (the secondary endpoint) were used to assess treatment response to MSC infusion and duration of the therapeutic effects. Ankylosing Spondylitis Disease Activity Score Containing C-reactive Protein (ASDAS-CRP) and other pre-established evaluation indices were also adopted to evaluate the clinical effects. Magnetic resonance imaging (MRI) was performed to detect changes of bone marrow edema in the spine. The safety of this treatment was also evaluated. Results: Thirty-one patients were included, and the percentage of ASAS20 responders reached 77.4% at the 4th week and the mean ASAS20 response duration was 7.1 weeks. The mean ASDAS-CRP score decreased from 3.6±0.6 to 2.4±0.5 at the 4th week, and then increased to 3.2±0.8 at the 20th week. The average total inflammation extent (TIE) detected by MRI decreased from 533,482.5 at baseline to 480,692.3 at the 4th week (p>0.05) and 400,547.2 at the 20th week (p<0.05). No adverse effects were noted. Conclusion: Intravenous infusion of MSCs is a feasible, safe, and promising treatment for patients with AS.
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All arthroscopic release of the glenohumeral joint for severe frozen shoulder: initial glenohumeral visualization through trans-cuff portal.
Arch Orthop Trauma Surg
PUBLISHED: 05-17-2013
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In recent two decades, a novel minimally invasive technique for resistant frozen shoulder, arthroscopic glenohumeral release, has been popularly practiced. However, by far one key point, although being well recognized, has not been tackled at all during the procedure-that is how to safely and smoothly insert the arthroscope into contracted and restricted glenohumeral joint when MUA cannot be performed or work, especially the severe stiff shoulder.
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The impact of the condenser on cytogenetic image quality in digital microscope system.
Anal Cell Pathol (Amst)
PUBLISHED: 05-17-2013
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Optimizing operational parameters of the digital microscope system is an important technique to acquire high quality cytogenetic images and facilitate the process of karyotyping so that the efficiency and accuracy of diagnosis can be improved.
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Experimental investigation of interactions between the temperature field and biofouling in a synthetic treated sewage stream.
Biofouling
PUBLISHED: 05-13-2013
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Biofouling causes significant losses in efficiency in heat exchangers recovering waste heat from treated sewage. The influence of the temperature field on biofouling was investigated using a flat plate heat exchanger which simulated the channels in a plate and frame unit. The test surface was a 316 stainless steel plate, and a solution of Bacillus sp. and Aeromonas sp. was used as a model process liquid. The test cell was operated under co-current, counter-current, and constant wall temperature configurations, which gave different temperature distributions. Biofouling was monitored via changes in heat transfer and biofilm thickness. The effect of uniform temperature on biofouling formation was similar to the effect of uniform temperature on planktonic growth of the organisms. Further results showed that the temperature field, and particularly the wall temperature, influenced the rate of biofouling strongly. The importance of wall temperature suggests that fouling could be mitigated by using different configurations in summer and winter.
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[Complications and treatment for button battery in the nose].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 05-09-2013
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To investigate the injury of button battery to nose and discuss its management.
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Purification and Identification of 72 kDa and 15 kDa Allergens from Broussonetia papyrifera Pollen.
Iran J Allergy Asthma Immunol
PUBLISHED: 05-06-2013
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"Broussonetia papyrifera" (Chinese mulberry) pollen is an important source of allergens in regions surrounding Shanghai, China. To identify and purify major allergens from "B. papyrifera" pollen that reacted with serum antibodies from sensitized patients, "B. papyrifera" pollen was defatted, dried, and extracted proteins were separated using SP cationic exchange or Q anionic exchange columns.Serum samples from 29 allergic patients and 4 healthy controls were collected. Allergens in eluted fractions were identified by Western blot and enzyme-linked immunosorbent assays (ELISA) using serum samples. An inhibitory assay was used to verify allergen-specific antiserum specificity.Serum IgE of 2 patients reacted with a 15 kDa protein band. The protein was eluted with 0.1M NaCl from a SP cationic exchange column. Serum samples from the same patients positively reacted with ELISA plate coated with partially purified 15 kDa protein. Serum IgE of 11 patients reacted with a 72 kDa protein band. The protein was eluted with 0.3M NaCl from a Q anionic exchange column. Serum samples from five patients positively reacted with ELISA coated with partially purified 72 kDa protein.Our preliminary purifications identified two proteins of 72 kDa and 15 kDa as allergens derived from "B. papyrifera" pollen, which reacted with allergic patients serum IgE. 
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Sericin for resistance switching device with multilevel nonvolatile memory.
Adv. Mater. Weinheim
PUBLISHED: 05-02-2013
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Resistance switching characteristics of natural sericin protein film is demonstrated for nonvolatile memory application for the first time. Excellent memory characteristics with a resistance OFF/ON ratio larger than 10(6) have been obtained and a multilevel memory based on sericin has been achieved. The environmentally friendly high performance biomaterial based memory devices may hold a place in the future of electronic device development.
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Evaluations of auto-focusing methods under a microscopic imaging modality for metaphase chromosome image analysis.
Anal Cell Pathol (Amst)
PUBLISHED: 05-01-2013
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Auto-focusing is an important operation in high throughput imaging scanning. Although many auto-focusing methods have been developed and tested for a variety of imaging modalities, few investigations have been performed on the selection of an optimal auto-focusing method that is suitable for the pathological metaphase chromosome analysis under a high resolution scanning microscopic system.
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Clinical operation of high throughput digital microscope system: The impact of the condenser on cytogenetic image quality.
Anal Cell Pathol (Amst)
PUBLISHED: 04-13-2013
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BACKGROUND: Optimizing operational parameters of the digital microscope system is an important technique to acquire high quality cytogenetic images and facilitate the process of karyotyping so that the efficiency and accuracy of diagnosis can be improved. OBJECTIVE: This study investigated the impact of condenser on cytogenetic image quality and system working performance using a prototype digital microscope image scanning system. METHODS: Both theoretical analysis and experimental validations through objectively evaluating a resolution test chart and subjectively observing large numbers of specimen were conducted. RESULTS: The results show that the optimal image quality and large depth of field (DOF) are simultaneously obtained when the numerical aperture of condenser is set as 60%~70% of the corresponding objective. Under this condition, more analyzable chromosomes and diagnostic information are obtained. As a result, the system shows higher working stability and less restriction for the implementation of algorithms such as autofocusing especially when the system is designed to achieve high throughput continuous image scanning. CONCLUSIONS: Although the above quantitative results were obtained using a specific prototype system under the experimental conditions reported in this paper, the presented evaluation methodologies can provide valuable guidelines for optimizing operational parameters in cytogenetic imaging using the high throughput continuous scanning microscopes in clinical practice.
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Nanofluidics for giant power harvesting.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 04-02-2013
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Nanochannels for power generation: The confinement of fluid motion in a single boron nitride nanotube can provide an efficient means of power harvesting owing to the osmotically driven streaming current under a salt concentration difference (see picture). Devices based on this principle may open a new avenue in the exploration for new sources of renewable energy.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.