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Nonparaxial propagation of elliptical Gaussian vortex beams in uniaxial crystal orthogonal to the optical axis.
J Opt Soc Am A Opt Image Sci Vis
PUBLISHED: 11-18-2014
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Analytical expressions for the three components of nonparaxial propagation of a polarized elliptical Gaussian vortex beam in uniaxial crystal orthogonal to the optical axis are derived. Intensity and phase distributions of the three components of a polarized elliptical Gaussian vortex beam propagating in a uniaxial crystal orthogonal to the optical axis are illustrated by numerical examples. The influences of the initial beam's parameters and the parameters of the uniaxial crystal on the evolution of the beam's intensity and phase distributions in the uniaxial crystal are examined in detail. Results show that the statistical properties of an elliptical Gaussian vortex beam nonparaxially propagating in uniaxial crystal orthogonal to the optical axis are closely determined by the initial beam's parameters and the parameters of the crystal. The beam waist width ?0 not only affects the size of the beam profile in uniaxial crystal but also determines the nonparaxial effect of an elliptical Gaussian vortex beam. The profile of an elliptical Gaussian vortex beam in the uniaxial crystal becomes twisted and tilted, whether the elliptical factor ? is greater or smaller than unity. The beam profile is tilted to the left in positive crystal. In contrast, it is inclined to the right in negative crystal. The results indicate that uniaxial crystal provides a convenient method to modulate the intensity and phase distributions of an elliptical Gaussian vortex beam, which is beneficial to optical manipulation of microscopic particles and nonlinear optics involving a specific beam profile and phase.
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NiCl2-Down-Regulated Antioxidant Enzyme mRNA Expression Causes Oxidative Damage in the Broiler(')s Kidney.
Biol Trace Elem Res
PUBLISHED: 09-05-2014
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The kidney serves as a major organ of nickel (Ni) excretion and is a target organ for acute Ni toxicity due to Ni accumulation. There are no studies on the Ni or Ni compound-regulated antioxidant enzyme mRNA expression in animals and human beings at present. This study was conducted to investigate the pathway of nickel chloride (NiCl2)-caused renal oxidative damage by the methods of biochemistry, quantitative real-time polymerase chain reaction, and enzyme-linked immunosorbent assay. Two hundred and eighty one-day-old broilers were randomly divided into four groups and fed on a control diet and three experimental diets supplemented with 300, 600, and 900 mg/kg of NiCl2 for 42 days. Dietary NiCl2 elevated the malondialdehyde (MDA), nitric oxide (NO), 8-hydroxy-2'-deoxyguanosine (8-OHdG) contents, and reduced the ability to inhibit hydroxy radical in the NiCl2-treated groups. Also, the renal inducible nitric oxide synthase (iNOS) activity and mRNA expression levels were increased. The total antioxidant (T-AOC) and activities of antioxidant enzymes including copper zinc superoxide dismutase (CuZn-SOD), manganese superoxide dismutase (Mn-SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GR), and glutathione-s-transferase (GST) were decreased, and the glutathione (GSH) contents as well were decreased in the kidney. Concurrently, the renal CuZn-SOD, Mn-SOD, CAT, GSH-Px, GST, and GR mRNA expression levels were decreased. The above-mentioned results showed that dietary NiCl2 in excess of 300 mg/kg caused renal oxidative damage by reducing mRNA expression levels and activities of antioxidant enzymes, and then enhancing free radicals generation, lipid peroxidation, and DNA oxidation.
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Toxicological effects of dietary nickel chloride on intestinal microbiota.
Ecotoxicol. Environ. Saf.
PUBLISHED: 08-28-2014
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This study was designed to evaluate the toxicological effect of dietary nickel chloride (NiCl2) on the counts of intestinal bacteria and diversity of microorganisms in broilers. Plate counting and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) assays were used. A total of 240 one-day-old avian broilers chicks were divided into four equal groups and kept on corn-soybean basal diet along with supplementation of 0, 300, 600 and 900 mg/kg NiCl2 for 42 days. Samples were taken at 21 and 42 days of age during the experiment. The bacterial count results showed that dietary NiCl2 in the range of 300 to 900 mg/kg decreased the counts of Bifidobacterium spp. and Lactobacillus, increased Escherichia coli (E. coli) and Enterococcus spp. in the ileum and cecum. PCR-DGGE analysis showed that bacterial band numbers, profile similarity, and the Shannon index of the ileum and cecum were all decreased in the 300, 600, and 900 mg/kg groups at 21 and 42 days of age. In conclusion, dietary NiCl2 affected the amount and diversity of intestinal microbiota in the ileum and cecum of broilers. This finding implies that NiCl2 has toxicological effect on the intestinal ecosystem and, possibly functions.
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Low enhancement on multiphase contrast-enhanced CT images: an independent predictor of the presence of high tumor grade of clear cell renal cell carcinoma.
AJR Am J Roentgenol
PUBLISHED: 08-23-2014
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The purpose of this study was to assess the relation between tumor enhancement on multiphase contrast-enhanced CT images and Fuhrman grade of clear cell renal cell carcinoma.
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Inhibition of c-Myc overcomes cytotoxic drug resistance in acute myeloid leukemia cells by promoting differentiation.
PLoS ONE
PUBLISHED: 08-15-2014
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Nowadays, drug resistance still represents a major obstacle to successful acute myeloid leukemia (AML) treatment and the underlying mechanism is not fully elucidated. Here, we found that high expression of c-Myc was one of the cytogenetic characteristics in the drug-resistant leukemic cells. c-Myc over-expression in leukemic cells induced resistance to chemotherapeutic drugs, enhanced colony formation capacity and inhibited cell differentiation induced by all-trans retinoic acid (ATRA). Meanwhile, inhibition of c-Myc by shRNA or specific c-Myc inhibitor 10058-F4 rescued the sensitivity to cytotoxic drugs, restrained the colony formation ability and promoted differentiation. RT-PCR and western blotting analysis showed that down-regulation of C/EBP? contributed to the poor differentiation state of leukemic cells induced by c-Myc over-expression. Importantly, over-expression of C/EBP? could reverse c-Myc induced drug resistance. In primary AML cells, the c-Myc expression was negatively correlated with C/EBP?. 10058-F4, displayed anti-proliferative activity and increased cellular differentiation with up-regulation of C/EBP? in primary AML cells. Thus, our study indicated that c-Myc could be a novel target to overcome drug resistance, providing a new approach in AML therapy.
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Effects of nickel chloride on the erythrocytes and erythrocyte immune adherence function in broilers.
Biol Trace Elem Res
PUBLISHED: 08-10-2014
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This study was conducted to investigate the immune adherence function of erythrocytes and erythrocyte induced by dietary nickel chloride (NiCl2) in broilers fed on a control diet and three experimental diets supplemented with 300, 600, and 900 mg/kg NiCl2 for 42 days. Blood samples were collected from five broilers in each group at 14, 28, and 42 days of age. Changes of erythrocyte parameters showed that total erythrocyte count (TEC), hemoglobin (Hb) contents, and packed cell volume (PCV) were significantly lower (p?
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[Gambogenic acid induces mitochondria-dependent apoptosis in human gastric carcinoma cell line].
Zhong Yao Cai
PUBLISHED: 08-06-2014
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To study the effects of Gambogenic acid (GNA) on the growth of human gastric carcinoma cell line MGC-803 and its underlying mechanisms.
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Electrophysiological differences between Hirayama disease, amyotrophic lateral sclerosis and cervical spondylotic amyotrophy.
BMC Musculoskelet Disord
PUBLISHED: 07-07-2014
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Hirayama disease (HD), amyotrophic lateral sclerosis (ALS) or cervical spondylotic amyotrophy (CSA) may result in atrophy of intrinsic hand and forearm muscles. The incidence of HD is low, and it is rarely encountered in the clinical setting. Consequently, HD is often misdiagnosed as ALS or CSA. It is important to differentiate these diseases because HD is caused by a benign focal lesion that is limited to the upper limbs.
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MDRL lncRNA regulates the processing of miR-484 primary transcript by targeting miR-361.
PLoS Genet.
PUBLISHED: 07-01-2014
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Long noncoding RNAs (lncRNAs) are emerging as new players in gene regulation, but whether lncRNAs operate in the processing of miRNA primary transcript is unclear. Also, whether lncRNAs are involved in the regulation of the mitochondrial network remains to be elucidated. Here, we report that a long noncoding RNA, named mitochondrial dynamic related lncRNA (MDRL), affects the processing of miR-484 primary transcript in nucleus and regulates the mitochondrial network by targeting miR-361 and miR-484. The results showed that miR-361 that predominantly located in nucleus can directly bind to primary transcript of miR-484 (pri-miR-484) and prevent its processing by Drosha into pre-miR-484. miR-361 is able to regulate mitochondrial fission and apoptosis by regulating miR-484 levels. In exploring the underlying molecular mechanism by which miR-361 is regulated, we identified MDRL and demonstrated that it could directly bind to miR-361 and downregulate its expression levels, which promotes the processing of pri-miR-484. MDRL inhibits mitochondrial fission and apoptosis by downregulating miR-361, which in turn relieves inhibition of miR-484 processing by miR-361. Our present study reveals a novel regulating model of mitochondrial fission program which is composed of MDRL, miR-361 and miR-484. Our work not only expands the function of the lncRNA pathway in gene regulation but also establishes a new mechanism for controlling miRNA expression.
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[Research progresses of pharmacokinetics of polysaccharides].
Yao Xue Xue Bao
PUBLISHED: 07-01-2014
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Pharmacokinetic analysis has attracted more and more attentions in the research field of bioactive natural product. However, there is limited study on the pharmacokinetics of polysaccharides. This paper focused on the research progresses of pharmacokinetics of polysaccharide, summarized the applications of chromatography, isotope labeling method, spectrophotometry, fluorospectrophotometry and biological assay in the analysis of polysaccharide pharmacokinetics, elucidated the behaviors of absorption, distribution, degradation and excretion of polysaccharide in experimental animals, and revealed the effects of physicochemical characteristic, administration dose and route on the pharmacokinetic properties of polysaccharide, which could be served as a reference for the related works.
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Hierarchical Zn/Ni-MOF-2 Nanosheet-Assembled Hollow Nanocubes for Multicomponent Catalytic Reactions.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 06-23-2014
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Metal-organic frameworks (MOFs) are potentially useful molecular materials that can exhibit structure flexibilities induced by some external stimuli. Such structure transformations can furnish MOFs with improved properties. The shape-controlled growth of MOFs combined with crystal-structure transformation is rarely achieved. Herein, we demonstrate the synthesis of hierarchical Zn/Ni-MOF-2 nanosheet-assembled hollow nanocubes (NAHNs) by a facile surfactant-free solvothermal approach. The unique nanostructures undergo crystal-structure transformation from Zn/Ni-MOF-5 nanocubes to Zn/Ni-MOF-2 nanosheets, which is analogous to the dissolution and recrystallization of inorganic nanocrystals. The present synthetic strategy to fabricate isostructural MOFs with hierarchical, hollow, and bimetallic nanostructures is expected to expand the diversity and range of potential applications of MOFs.
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Selenium addition alters mercury uptake, bioavailability in the rhizosphere and root anatomy of rice (Oryza sativa).
Ann. Bot.
PUBLISHED: 06-19-2014
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Mercury (Hg) is an extremely toxic pollutant, especially in the form of methylmercury (MeHg), whereas selenium (Se) is an essential trace element in the human diet. This study aimed to ascertain whether addition of Se can produce rice with enriched Se and lowered Hg content when growing in Hg-contaminated paddy fields and, if so, to determine the possible mechanisms behind these effects.
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Highly Flexible Sub-1 nm Tungsten Oxide Nanobelts as Efficient Desulfurization Catalysts.
Small
PUBLISHED: 05-09-2014
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Ultrathin tungsten oxide nanobelts are successfully synthesized via a facile solvothermal method. Sub-1 nm thickness and hydrophobic surface property endow the nanobelts with flexibility, viscosity, gelation, and good catalytic performance in oxidative desulfurization.
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Expression of each cistron in the gal operon can be regulated by transcription termination and generation of a galk-specific mRNA, mK2.
J. Bacteriol.
PUBLISHED: 05-02-2014
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The gal operon of Escherichia coli has 4 cistrons, galE, galT, galK, and galM. In our previous report (H. J. Lee, H. J. Jeon, S. C. Ji, S. H. Yun, H. M. Lim, J. Mol. Biol. 378: 318-327, 2008), we identified 6 different mRNA species, mE1, mE2, mT1, mK1, mK2, and mM1, in the gal operon and mapped these mRNAs. The mRNA map suggests a gradient of gene expression known as natural polarity. In this study, we investigated how the mRNAs are generated to understand the cause of natural polarity. Results indicated that mE1, mT1, mK1, and mM1, whose 3' ends are located at the end of each cistron, are generated by transcription termination. Since each transcription termination is operating with a certain frequency and those 4 mRNAs have 5' ends at the transcription initiation site(s), these transcription terminations are the basic cause of natural polarity. Transcription terminations at galE-galT and galT-galK junctions, making mE1 and mT1, are Rho dependent. However, the terminations to make mK1 and mM1 are partially Rho dependent. The 5' ends of mK2 are generated by an endonucleolytic cleavage of a pre-mK2 by RNase P, and the 3' ends are generated by Rho termination 260 nucleotides before the end of the operon. The 5' portion of pre-mK2 is likely to become mE2. These results also suggested that galK expression could be regulated through mK2 production independent from natural polarity.
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[Effect of chaperone-mediated autophagy in MPP(+) -induced SH-SY5Y cells and interventional effect of puerarin].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 04-24-2014
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To study the protective effect of puerarin on MPP(+) -induced SH-SY5Y cells by chaperone-mediated autophagy (CMA).
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PiRNAs link epigenetic modifications to reprogramming.
Histol. Histopathol.
PUBLISHED: 04-23-2014
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Cell reprogramming is a process involved in changing epigenetic landscapes, including histone modification, DNA methylation, and expression of non-coding RNAs; and reprogramming finally leads to changes in gene expression profile and cell fate. A great challenge to this field is to overcome epigenetic suppression exerted by highly differentiated cells of those key regions that are critical for establishment and maintenance of final cell types or induced pluripotent stem cells (iPSCs). As a new class of small non-coding RNAs, piwi-interacting RNAs (piRNAs) have been shown to play important roles in transposon silencing, transcriptional/post-transcriptional regulation, and epigenetic modifications. In this review, we discuss recent advances in which piRNAs were proposed or shown to be barriers to reprogramming suppression through epigenetic silencing, and it may be necessary to overcome this piRNA-derived barrier to achieve final cellular status during reprogramming. Therefore, gaining deeper insights into the mechanism(s) by which piRNAs mediate epigenetic regulation of gene expression, genome stability and chromatin status may offer a new avenue for efficient reprogramming of somatic cells toward a pluripotent state.
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Engineering nanointerfaces for nanocatalysis.
Chem Soc Rev
PUBLISHED: 04-19-2014
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The interface, referred to as the boundary between two phases, has been demonstrated to play a critical role in catalysis. Fundamental understanding of interfacial phenomena occurring in catalysis will favor the rational design of high-performance catalysts. With the thriving of nanoscience, the nanointerface has also received tremendous attention in nanocatalysis. In this review, we focus on the recent advances in the delicate design and the fine control of various complex nanomaterials with well-defined interfaces based on progress in nano-synthetic methodologies, including metal-metal oxide, metal-metal, metal-non-oxide and metal in confined spaces. Then the challenging issues in the synthetic control of a nanointerface, based on the authors' experiences, are discussed. Finally, the prospects and outlooks for engineering nanointerfaces for nanocatalysis towards renewable energy are presented.
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Magnetic resonance neurography in analysis of operative safety of transforaminal lumbar interbody fusion in Chinese subjects.
Orthop Surg
PUBLISHED: 04-08-2014
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To measure relevant anatomical variables of lumbosacral nerve root and adjacent structures by magnetic resonance neurography (MRN) and analyze operative safety of transforaminal lumbar interbody fusion (TLIF) in Chinese subjects.
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Correction: Determining the degradation efficiency and mechanisms of ethyl violet using HPLC-PDA-ESI-MS and GC-MS.
Chem Cent J
PUBLISHED: 04-07-2014
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This is a correction to the following paper: Determining the degradation efficiency and mechanisms of ethyl violet using HPLC-PDA-ESI-MS and GC-MS, Wen-Hsin Chung, Chung-Shin Lu, Wan-Yu Lin, Jian-Xun Wang, Chia-Wei Wu, Chiing-Chang Chen, Chemistry Central Journal 2012, 6:63 (30 June 2012).
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Nonparaxial propagation of Lorentz-Gauss beams in uniaxial crystal orthogonal to the optical axis.
J Opt Soc Am A Opt Image Sci Vis
PUBLISHED: 04-04-2014
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Analytical expressions for the three components of nonparaxial propagation of a polarized Lorentz-Gauss beam in uniaxial crystal orthogonal to the optical axis are derived and used to investigate its propagation properties in uniaxial crystal. The influences of the initial beam parameters and the parameters of the uniaxial crystal on the evolution of the beam-intensity distribution in the uniaxial crystal are examined in detail. Results show that the statistical properties of a nonparaxial Lorentz-Gauss beam in a uniaxial crystal orthogonal to the optical axis are closely determined by the initial beam's parameters and the parameters of the crystal: the beam waist sizes-w(0), w(0x), and w(0y)-not only affect the size and shape of the beam profile in uniaxial crystal but also determine the nonparaxial effect of a Lorentz-Gauss beam; the beam profile of a Lorentz-Gauss beam in uniaxial crystal is elongated in the x or y direction, which is determined by the ratio of the extraordinary refractive index to the ordinary refractive index; with increasing deviation of the ratio from unity, the extension of the beam profile augments. The results indicate that uniaxial crystal provides an effective and convenient method for modulating the Lorentz-Gauss beams. Our results may be valuable in some fields, such as optical trapping and nonlinear optics, where a light beam with a special profile and polarization is required.
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Effect of dietary nickel chloride on splenic immune function in broilers.
Biol Trace Elem Res
PUBLISHED: 03-20-2014
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This study was designed to evaluate the effects of dietary nickel chloride (NiCl2) on the splenic immunity in broilers by observing changes of cytokine mRNA expression and protein levels, immunoglobulin (IgA, IgG, and IgM) contents, and IgA+ B cell and T-cell numbers using the methods of qRT-PCR, flow cytometry (FCM), and ELISA. A total of 240 1-day-old avian broilers were equally allocated into four groups and fed on a corn-soybean basal diet as the control diet or the same diet supplemented with 300, 600, and 900 mg/kg NiCl2 for 42 days. The mRNA expression and protein levels of IL-2, IL-6, IL-10, IL-12, TNF-?/LITAF, IFN-?, and IgA, IgG, and IgM contents were significantly decreased (p<0.05 or p<0.01) in the 300-, 600-, and 900-mg/kg NiCl2 groups when compared with those of the control group, which was consistent with the reduction of T-cell subset percentages and IgA+ B cell numbers in the 300-, 600-, and 900-mg/kg NiCl2 groups. The abovementioned results showed that dietary NiCl2 in excess of 300 mg/kg caused damage on splenocytes and splenic immune function. The results of the present study provided new experimental evidences for further study on the effect mechanism of NiCl2 on splenic immunity.
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IRF4 is a key thermogenic transcriptional partner of PGC-1?.
Cell
PUBLISHED: 03-14-2014
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Brown fat can reduce obesity through the dissipation of calories as heat. Control of thermogenic gene expression occurs via the induction of various coactivators, most notably PGC-1?. In contrast, the transcription factor partner(s) of these cofactors are poorly described. Here, we identify interferon regulatory factor 4 (IRF4) as a dominant transcriptional effector of thermogenesis. IRF4 is induced by cold and cAMP in adipocytes and is sufficient to promote increased thermogenic gene expression, energy expenditure, and cold tolerance. Conversely, knockout of IRF4 in UCP1(+) cells causes reduced thermogenic gene expression and energy expenditure, obesity, and cold intolerance. IRF4 also induces the expression of PGC-1? and PRDM16 and interacts with PGC-1?, driving Ucp1 expression. Finally, cold, ?-agonists, or forced expression of PGC-1? are unable to cause thermogenic gene expression in the absence of IRF4. These studies establish IRF4 as a transcriptional driver of a program of thermogenic gene expression and energy expenditure.
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Finding motifs in DNA sequences using low-dispersion sequences.
J. Comput. Biol.
PUBLISHED: 03-05-2014
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Motif finding problems, abstracted as the planted (l, d)-motif finding problem, are a major task in molecular biology--finding functioning units and genes. In 2002, the random projection algorithm was introduced to solve the challenging (15, 4)-motif finding problem by using randomly chosen templates. Two years later, a so-called uniform projection algorithm was developed to improve the random projection algorithm by means of low-dispersion sequences generated by coverings. In this article, we introduce an improved projection algorithm called the low-dispersion projection algorithm, which uses low-dispersion sequences generated by developed almost difference families. Compared with the random projection algorithm, the low-dispersion projection algorithm can solve the (l, d)-motif finding problem with fewer templates without decreasing the success rate.
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Toxicological effects of nickel chloride on the cytokine mRNA expression and protein levels in intestinal mucosal immunity of broilers.
Environ. Toxicol.
PUBLISHED: 03-01-2014
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The purpose of this study was to examine the toxicological effects of nickel chloride (NiCl2 ; 300, 600, and 900 mg kg(-1) diet) on the cytokine mRNA expression and protein levels in the intestinal mucosa and cecal tonsil, and on the ileac and cecal tonsil T cells in broilers by the methods of qRT-PCR, flow cytometry and ELISA for 42 days. Results showed that the IL-2, IL-6, IL-10, IL-17, IFN-?, and TNF-? (LITAF) cytokine mRNA expression and protein levels were lower (P?
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Downregulation of TLR4 and 7 mRNA expression levels in broiler's spleen caused by diets supplemented with nickel chloride.
Biol Trace Elem Res
PUBLISHED: 02-28-2014
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Toll-like receptors (TLRs) are important immune receptors in discriminating self from nonself and in initiating the innate and adaptive immune response. TLR4 and TLR7 have been proven to be highly expressed in chicken's spleen. Thus, this study was to evaluate the TLR4 and TLR7 messenger RNA (mRNA) expression levels in the spleen of broilers fed diets supplemented with nickel chloride (NiCl2) using the methods of quantitative real-time PCR (qRT-PCR). Two hundred forty-one-day-old avian broilers were equally divided into 4 groups and fed on a corn-soybean basal diet as control diet or the same basal diet supplemented with 300, 600, and 900 mg/kg of NiCl2 for 42 days. Results showed that TLR4 and TLR7 mRNA expression levels in the spleen were lower (P?
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Mitochondrial dysfunction in obesity-associated nonalcoholic fatty liver disease: the protective effects of pomegranate with its active component punicalagin.
Antioxid. Redox Signal.
PUBLISHED: 02-18-2014
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Punicalagin (PU) is one of the major ellagitannins found in the pomegranate (Punica granatum), which is a popular fruit with several health benefits. So far, no studies have evaluated the effects of PU on nonalcoholic fatty liver disease (NAFLD). Our work aims at studying the effect of PU-enriched pomegranate extract (PE) on high fat diet (HFD)-induced NAFLD.
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A 1D/2D helical CdS/ZnIn2 S4 nano-heterostructure.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 01-29-2014
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Multidimensional nano-heterostructures (NHSs) that have unique dimensionality-dependent integrative and synergic effects are intriguing but still underdeveloped. Here, we report the first helical 1D/2D epitaxial NHS between CdS and ZnIn2S4. Experimental and theoretical studies reveal that the mismatches in lattice and dangling bonds between 1D and 2D units govern the growth procedure. The resulting well-defined interface induces the delocalized interface states, thus facilitate the charge transfer and enhance the performance in the photoelectrochemical cells. We foresee that the mechanistic insights gained and the electronic structures revealed would inspire the design of more complex 1D/2D NHSs with outstanding functionalities.
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Whole-genome sequencing of Berkshire (European native pig) provides insights into its origin and domestication.
Sci Rep
PUBLISHED: 01-23-2014
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Domesticated organisms have experienced strong selective pressures directed at genes or genomic regions controlling traits of biological, agricultural or medical importance. The genome of native and domesticated pigs provide a unique opportunity for tracing the history of domestication and identifying signatures of artificial selection. Here we used whole-genome sequencing to explore the genetic relationships among the European native pig Berkshire and breeds that are distributed worldwide, and to identify genomic footprints left by selection during the domestication of Berkshire. Numerous nonsynonymous SNPs-containing genes fall into olfactory-related categories, which are part of a rapidly evolving superfamily in the mammalian genome. Phylogenetic analyses revealed a deep phylogenetic split between European and Asian pigs rather than between domestic and wild pigs. Admixture analysis exhibited higher portion of Chinese genetic material for the Berkshire pigs, which is consistent with the historical record regarding its origin. Selective sweep analyses revealed strong signatures of selection affecting genomic regions that harbor genes underlying economic traits such as disease resistance, pork yield, fertility, tameness and body length. These discoveries confirmed the history of origin of Berkshire pig by genome-wide analysis and illustrate how domestication has shaped the patterns of genetic variation.
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Growing rice aerobically markedly decreases mercury accumulation by reducing both Hg bioavailability and the production of MeHg.
Environ. Sci. Technol.
PUBLISHED: 01-17-2014
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Rice consumption represents a major route of mercury (Hg) and methylmercury (MeHg) exposure for those living in certain areas of inland China. In this study we investigated the effects of water management on bioavailable Hg, MeHg, and sulfate-reducing bacteria (SRB, abundance and community composition) in rhizosphere soil, and total Hg (THg) and MeHg in rice plants grown under glasshouse and paddy field conditions. Aerobic conditions greatly decreased the amount of THg and MeHg taken up by rice plants and affected their distribution in different plant tissues. There were positive correlations between bioavailable Hg and THg in brown rice and roots and between numbers of SRB and MeHg in brown rice, roots, and rhizosphere soil. Furthermore, the community composition of SRB was dramatically influenced by the water management regimes. Our results demonstrate that the greatly reduced bioavailability of Hg and production of MeHg are due to decreased SRB numbers and proportion of Hg methylators in the rhizosphere under aerobic conditions. These are the main reasons for the reduced Hg and MeHg accumulation in aerobically grown rice. Water management is indicated as an effective measure that can be used to reduce Hg and MeHg uptake by rice plants from Hg-contaminated paddy fields.
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MiR-22 suppresses the proliferation and invasion of gastric cancer cells by inhibiting CD151.
Biochem. Biophys. Res. Commun.
PUBLISHED: 01-16-2014
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Gastric cancer (GC) is the second common cause of cancer-related death worldwide. microRNAs (miRNAs) play important roles in the carcinogenesis of GC. Here, we found that miR-22 was significantly decreased in GC tissue samples and cell lines. Ectopic overexpression of miR-22 remarkably suppressed cell proliferation and colony formation of GC cells. Moreover, overexpression of miR-22 significantly suppressed migration and invasion of GC cells. CD151 was found to be a target of miR-22. Furthermore, overexpression of CD151 significantly attenuated the tumor suppressive effect of miR-22. Taken together, miR-22 might suppress GC cells growth and motility partially by inhibiting CD151.
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Superparamagnetic iron oxide nanoparticles exacerbate the risks of reactive oxygen species-mediated external stresses.
Arch. Toxicol.
PUBLISHED: 01-12-2014
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Superparamagnetic iron oxide nanoparticles (IONPs) have been widely applied in numerous biomedical fields. The evaluation of the toxicity of IONPs to the environment and human beings is indispensable to guide their applications. IONPs are usually considered to have good biocompatibility; however, some literatures have reported the toxicity of IONPs in vitro and in vivo. The controversy surrounding the biocompatibility of IONPs prompted us to carefully consider the biological effects of IONPs, especially under stress conditions. However, the potential risks of IONPs under stress conditions have not yet been evaluated in depth. Acrolein is widespread in the environment and modulates stress-induced gene activation and cell death in many organs and tissues. In this study, we assessed the sensitivity of H9c2 cardiomyocyte cells embedded with IONPs to acrolein and investigated the possible molecular mechanisms involved in this sensitivity. IONPs, which alone exhibited no toxicity, sensitized the H9c2 cardiomyocytes to acrolein-induced dysfunction. The IONP/acrolein treatment induced a loss of viability, membrane disruption, reactive oxygen species (ROS) generation, Erk activation, mitochondrial and lysosomal dysfunction, and necrosis in H9c2 cells. Treatment with an ROS generation inhibitor (diphenyleneiodonium) or an iron chelator (deferoxamine) prevented the IONP/acrolein-induced loss of viability, suggesting that ROS and IONP degradation facilitated the toxicity of the IONP/acrolein treatment in H9c2 cells. Our data suggest that cells embedded in IONPs are more vulnerable to oxidative stress, which confirms the hypothesis that nanoparticles can sensitize cells to the adverse effects of external stimulation. The present work provides a new perspective from which to evaluate the interactions between nanoparticles and cells.
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Unusual enrichment and assembly of TiO2 nanocrystals at water/hydrophobic interfaces in a pure inorganic phase.
Langmuir
PUBLISHED: 01-09-2014
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We report an unusual enrichment and assembly of TiO2 nanocrystals at water/hydrophobic interfaces through oxidative hydrolysis of TiCl3 in water. The assembly is a spontaneous process that involves on-water inorganic reaction and assembly in the absence of any organic phases. In this process, TiO2 nanoparticles are preferentially produced at water/hydrophobic interfaces. When the surface tension of the aqueous phase is above a critical value, ca. 25-35 mN m(-1), these TiO2 nanocrystals can spontaneously accumulate at water/air interfaces to produce macroscopic sized sheets and tubes.
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Double stranded RNA-dependent protein kinase promotes the tumorigenic phenotype in HepG2 hepatocellular carcinoma cells by activating STAT3.
Oncol Lett
PUBLISHED: 01-02-2014
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Previously known as a first-response protein upon viral infection and other stress signals, double-stranded RNA-dependent protein kinase (PKR, also termed EIF2AK2) has been found to be differentially expressed in multiple types of tumor, including hepatocellular carcinoma, suggesting that PKR may be involved in tumor initiation and development. However, whether and how PKR promotes or suppresses the development of hepatocellular carcinoma remains controversial. In the present study, PKR expression was investigated using qPCR and western blot analysis, which revealed that PKR expression was upregulated in liver tumor tissues, when compared to that of adjacent normal tissues, which were obtained from four primary liver cancer patients. Furthermore, in vitro cellular assays revealed that PKR exerts a key role in maintaining the proliferation and migration of HepG2 human hepatocellular carcinoma cells. Mouse models with xenograft transplantations also confirmed a tumorigenic role of PKR in HepG2 cells. Furthermore, a transcription factor, signal transducer and activator of transcription 3 (STAT3), was revealed to mediate the tumor-promoting function of PKR in HepG2 cells, as shown by in vitro cellular proliferation and migration assays. In conclusion, the results suggested a tumorigenic role of PKR in liver cancer and a detailed mechanism involving an oncogenic transcription factor, STAT3, is described. Therefore, PKR may present a potential novel therapeutic target for the treatment of liver cancer.
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Carvacrol alleviates ischemia reperfusion injury by regulating the PI3K-Akt pathway in rats.
PLoS ONE
PUBLISHED: 01-01-2014
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Liver ischemia reperfusion (I/R) injury is a common pathophysiological process in many clinical settings. Carvacrol, a food additive commonly used in essential oils, has displayed antimicrobials, antitumor and antidepressant-like activities. In the present study, we investigated the protective effects of carvacrol on I/R injury in the Wistar rat livers and an in vitro hypoxia/restoration (H/R) model.
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Van der Waals density functional study of the structural and electronic properties of La-doped phenanthrene.
J Chem Phys
PUBLISHED: 12-03-2013
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By the first principle calculations based on the van der Waals density functional theory, we study the crystal structures and electronic properties of La-doped phenanthrene. Two stable atomic geometries of La1phenanthrene are obtained by relaxation of atomic positions from various initial structures. The structure-I is a metal with two energy bands crossing the Fermi level, while the structure-II displays a semiconducting state with an energy gap of 0.15 eV, which has an energy gain of 0.42 eV per unit cell compared to the structure-I. The most striking feature of La1phenanthrene is that La 5d electrons make a significant contribution to the total density of state around the Fermi level, which is distinct from potassium doped phenanthrene and picene. Our findings provide an important foundation for the understanding of superconductivity in La-doped phenanthrene.
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Ultrathin pt-cu nanosheets and nanocones.
J. Am. Chem. Soc.
PUBLISHED: 12-02-2013
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In this work, we have successfully synthesized free-standing ultrathin Pt-Cu alloy nanosheets of 4-6 atom thickness with tunable lateral size from 10 to 50 nm. The nanosheets with diameters >20 nm can be converted into nanocones in a controllable way. These nanosheets and nanocones exhibit excellent electrocatalytic activities for the oxidation of ethanol in comparison to commercial Pt black and Pt/C catalysts.
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Laser direct patterning of indium tin oxide for defining a channel of thin film transistor.
J Nanosci Nanotechnol
PUBLISHED: 11-20-2013
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In this work, using a Q-switched diode-pumped neodymium-doped yttrium vanadate (Nd:YVO4, lambda = 1064 nm) laser, a direct patterning of indium tin oxide (ITO) channel was realized on glass substrates and the results were compared and analyzed in terms of the effect of repetition rate, scanning speed on etching characteristics. The results showed that the laser conditions of 40 kHz repetition rate with a scanning speed of 500 mm/s were appropriate for the channeling of ITO electrodes. The length of laser-patterned channel was maintained at about 55 microm. However, residual spikes (about 50 nm in height) of ITO were found to be formed at the edges of the laser ablated area and a few ITO residues remained on the glass substrate after laser scanning. By dipping the laser-ablated ITO film in ITO diluted etchant (ITO etchant/DI water: 1/10) at 50 degrees C for 3 min, the spikes and residual ITO were effectively removed. At last, using the laser direct patterning, a bottom-source-drain indium gallium zinc oxide thin film transistor (IGZO-TFT) was fabricated. It is successfully demonstrated that the laser direct patterning can be utilized instead of photolithography to simplify the fabrication process of TFT channel, resulting in the increase of productivity and reduction of cost.
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Nd:YVO4 laser direct ablation of indium tin oxide films deposited on glass and polyethylene terephthalate substrates.
J Nanosci Nanotechnol
PUBLISHED: 11-12-2013
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A Q-switched diode-pumped neodymium-doped yttrium vanadate (Nd:YVO4, lambda = 1064 nm) laser was applied to obtain the indium tin oxide (ITO) patterns on flexible polyethylene terephthalate (PET) substrate by a direct etching method. After the ITO films were deposited on a soda-lime glass and PET substrate, laser ablations were carried out on the ITO films for various conditions and the laser ablated results on the ITO films were investigated and analyzed considering the effects of substrates on the laser etching. The laser ablated widths on ITO deposited on glass were found to be much narrower than those on ITO deposited on PET substrate, especially, at a higher scanning speed of laser beam such as 1000 mm/s and 2000 mm/s. As the thermal conductivity of glass substrate is about 7.5 times higher than that of PET, more thermal energy would be spread and transferred to lateral direction in the ITO film in case of PET substrate.
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A Shape-Preserving Preprocessing for Human Pulse Signals Based on Adaptive Parameter Determination.
IEEE Trans Biomed Circuits Syst
PUBLISHED: 10-23-2013
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The use of the human pulse signal for medical diagnosis is a mainstay in the practice of traditional Chinese medicine. Computer processing of this signal may be used to automate diagnostic procedures and to reveal sources of information in the waveform that have been used by both eastern and western physicians for more than two millennia. A new method for preprocessing of the human pulse signal significantly improves feature extraction and classification of the waveform. Baseline distortion is first removed using the dual-tree complex wavelet transform (DT-CWT) and cubic spline interpolation, then a novel filtering method removes the residual background noise. Filtering is implemented in two stages. In the initial pass, a majority of the noise is eliminated by an adaptive mean filter whose sliding window duration is selected automatically based on a chain code and the DT-CWT. In the second pass, residual high frequency noise is removed using the DT-CWT with a new threshold determination. Experimental results demonstrate effective removal of background disturbances with excellent preservation of pulse peak information essential for proper parametric representation and classification of the waveform.
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Well-Defined Metal-Organic Framework Hollow Nanocages.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 10-02-2013
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Metal-organic frameworks (MOFs) have demonstrated great potentials in a variety of important applications. To enhance the inherent properties and endow materials with multifunctionality, the rational design and synthesis of MOFs with nanoscale porosity and hollow feature is highly desired and remains a great challenge. In this work, the formation of a series of well-defined MOF (MOF-5, Fe(II) -MOF-5, Fe(III) -MOF-5) hollow nanocages by a facile solvothermal method, without any additional supporting template is reported. A surface-energy-driven mechanism may be responsible for the formation of hollow nanocages. The addition of pre-synthesized poly(vinylpyrrolidone)- (PVP) capped noble-metal nanoparticles into the synthetic system of MOF hollow nanocages yields the yolk-shell noble metal@MOF nanostructures. The present strategy to fabricate hollow and yolk-shell nanostructures is expected to open up exciting opportunities for developing a novel class of inorganic-organic hybrid functional nanomaterials.
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Effects of lutein and lycopene on carotid intima-media thickness in Chinese subjects with subclinical atherosclerosis: a randomised, double-blind, placebo-controlled trial.
Br. J. Nutr.
PUBLISHED: 09-19-2013
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The aim of the present study was to evaluate the effects of lutein and lycopene supplementation on carotid artery intima-media thickness (CAIMT) in subjects with subclinical atherosclerosis. A total of 144 subjects aged 45-68 years were recruited from local communities. All the subjects were randomly assigned to receive 20 mg lutein/d (n 48), 20 mg lutein/d+20 mg lycopene/d (n 48) or placebo (n 48) for 12 months. CAIMT was measured using Doppler ultrasonography at baseline and after 12 months, and serum lutein and lycopene concentrations were determined using HPLC. Serum lutein concentrations increased significantly from 0·34 to 1·96 ?mol/l in the lutein group (P< 0·001) and from 0·35 to 1·66 ?mol/l in the combination group (P< 0·001). Similarly, serum lycopene concentrations increased significantly from 0·18 to 0·71 ?mol/l in the combination group at month 12 (P< 0·001), whereas no significant change was observed in the placebo group. The mean values of CAIMT decreased significantly by 0·035 mm (P= 0·042) and 0·073 mm (P< 0·001) in the lutein and combination groups at month 12, respectively. The change in CAIMT was inversely associated with the increase in serum lutein concentrations (P< 0·05) in both the active treatment groups and with that in serum lycopene concentrations (? = - 0·342, P= 0·031) in the combination group. Lutein and lycopene supplementation significantly increased the serum concentrations of lutein and lycopene with a decrease in CAIMT being associated with both concentrations. In addition, the combination of lutein and lycopene supplementation was more effective than lutein alone for protection against the development of CAIMT in Chinese subjects with subclinical atherosclerosis, and further studies are needed to confirm whether synergistic effects of lutein and lycopene exist.
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Inhibition of mTOR pathway sensitizes acute myeloid leukemia cells to aurora inhibitors by suppression of glycolytic metabolism.
Mol. Cancer Res.
PUBLISHED: 09-05-2013
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Aurora kinases are overexpressed in large numbers of tumors and considered as potential therapeutic targets. In this study, we found that the Aurora kinases inhibitors MK-0457 (MK) and ZM447439 (ZM) induced polyploidization in acute myeloid leukemia (AML) cell lines. The level of glycolytic metabolism was significantly increased in the polyploidy cells, which were sensitive to glycolysis inhibitor 2-deoxy-D-glucose (2DG), suggesting that polyploidy cells might be eliminated by metabolism deprivation. Indeed, inhibition of mTOR pathway by mTOR inhibitors (rapamycin and PP242) or 2DG promoted not only apoptosis but also autophagy in the polyploidy cells induced by Aurora inhibitors. Mechanically, PP242 or2DGdecreased the level of glucose uptake and lactate production in polyploidy cells as well as the expression of p62/SQSTM1. Moreover, knockdown of p62/SQSTM1 sensitized cells to the Aurora inhibitor whereas overexpression of p62/SQSTM1 reduced drug efficacy. Thus, our results revealed that inhibition of mTOR pathway decreased the glycolytic metabolism of the polyploidy cells, and increased the efficacy of Aurora kinases inhibitors, providing a novel approach of combination treatment in AML.
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Biomimetic Multifunctional Nanochannels Based on the Asymmetric Wettability of Heterogeneous Nanowire Membranes.
Adv. Mater. Weinheim
PUBLISHED: 08-25-2013
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A charged heterogeneous nanowire membrane with asymmetric wettability serves as a biomimetic passive channel when the bilayer is hydrophilic; It also functions as pH valve based on the hydrophobic CaWO4 layer (contact angle of 145.3?±0.3?) and hydrophilic MnO2 layer. Moreover, a reversible ionic rectification is realized in the above-mentioned semi-hydrophobic and hydrophilic state with strong acid environment or in the complete hydrophobic stage with a moderate discrepancy (CA of CaWO4 and MnO2 layer are 141.3?±0.3? and 157.6?±2.0?, respectively) in near neuter condition.
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Replantation of a circumferentially degloved ring finger by venous arterializations.
Indian J Orthop
PUBLISHED: 08-21-2013
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Treatment of ring degloving injuries of the finger is one of the most demanding problems in hand surgery. Replantation has been advocated as the best solution if the vessels belonging to the degloved skin are not irreversibly destroyed. We present a case involving a ring finger with circumferentially avulsed skin. Debridement under microscopy showed that the peeled skin did not retain any arteries, but did have various superficial veins of good caliber. The neurovascular bundles of the finger remained in situ and did not appear to be disrupted. The degloved finger survived uneventfully by venous arterialization, retaining excellent function and appearance.
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Three-Dimensional Assembly of Single-Layered MoS2.
Adv. Mater. Weinheim
PUBLISHED: 08-15-2013
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Assembly of single layers: Three-dimensional assembly of single-layered MoS2 is achieved on a large scale via a solution method. The as-prepared tubular architectures have tunable size and mesopores in the shell, which are desirable for applications. As a example, they exhibit excellent lithium storage properties and are highly active for hydrodesulfurization of thiophene resulting from their structural advantages.
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Layered pnictide-oxide Na2Ti2Pn2O (Pn=As, Sb): a candidate for spin density waves.
J Phys Condens Matter
PUBLISHED: 08-08-2013
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From first-principles calculations, we have studied the electronic and magnetic structures of compound Na2Ti2Pn2O (Pn=As or Sb), whose crystal structure is a bridge between or a combination of those of high-Tc superconducting cuprates and iron pnictides. We find that in the ground state Na2Ti2As2O is a novel blocked checkerboard antiferromagnetic semiconductor with a small band gap of about 0.15 eV. In contrast, Na2Ti2Sb2O is a bi-collinear antiferromagnetic semimetal, with a small moment of about 0.5 ?(B) around each Ti atom. We show that there is a strong Fermi surface nesting in Na2Ti2Pn2O, and we verify that the blocked checkerboard and bi-collinear antiferromagnetic states both are the spin density waves induced by the Fermi surface nesting. A tetramer structural distortion is found in company with the formation of a blocked checkerboard antiferromagnetic order, in good agreement with the experimentally observed commensurate structural distortion but with space group symmetry retained after the anomaly happens.
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Hierarchical MnO2/SnO2 heterostructures for a novel free-standing ternary thermite membrane.
Inorg Chem
PUBLISHED: 08-01-2013
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We report the synthesis of a novel hierarchical MnO2/SnO2 heterostructures via a hydrothermal method. Secondary SnO2 nanostructure grows epitaxially on the surface of MnO2 backbones without any surfactant, which relies on the minimization of surface energy and interfacial lattice mismatch. Detailed investigations reveal that the cover density and morphology of the SnO2 nanostructure can be tailored by changing the experimental parameter. Moreover, we demonstrate a bottom-up method to produce energetic nanocomposites by assembling nanoaluminum (n-Al) and MnO2/SnO2 hierarchical nanostructures into a free-standing MnO2/SnO2/n-Al ternary thermite membrane. This assembled approach can significantly reduce diffusion distances and increase their intimacy between the components. Different thermite mixtures were investigated to evaluate the corresponding activation energies using DSC techniques. The energy performance of the ternary thermite membrane can be manipulated through different components of the MnO2/SnO2 heterostructures. Overall, our work may open a new route for new energetic materials.
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Sintering-resistant Ni-based reforming catalysts obtained via the nanoconfinement effect.
Chem. Commun. (Camb.)
PUBLISHED: 07-24-2013
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This communication describes the design and synthesis of anti-sintering and -coke nickel phyllosilicate (PS) nanotubes (Ni/PSn) for hydrogen production via reforming reactions. The introduction of nickel particles in PS nanotubes could effectively maintain the Ni size and increase the resistance of metal particles for carbon deposition.
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Inorganic nanostructures with sizes down to 1 nm: a macromolecule analogue.
J. Am. Chem. Soc.
PUBLISHED: 07-23-2013
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Ultrathin nanostructures exhibit many interesting properties which are absent or less-pronounced in traditional nanomaterials of larger sizes. In this work, we report the synthesis of ultrathin nanowires and nanoribbons of rare earth hydroxides and demonstrate some new phenomena caused by their atomic-level lateral size (1 nm), including ligand-induced gelation, self-assembly framework, and conformational diversity. These features are typically, although not exclusively, found in polymer solutions. The properties of the inorganic backbone and the emerging polymeric characteristics combined prove to be very promising in the design of new hybrid materials.
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A pre-microRNA-149 (miR-149) genetic variation affects miR-149 maturation and its ability to regulate the Puma protein in apoptosis.
J. Biol. Chem.
PUBLISHED: 07-19-2013
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MicroRNAs (miRNAs) are small, single-stranded, noncoding RNAs that function as negative regulators of gene expression. They are transcribed from endogenous DNA and form hairpin structures (termed as pre-miRNAs) that are processed to form mature miRNAs. It remains largely unknown as to the molecular consequences of the natural genetic variation in pre-miRNAs. Here, we report that an A?G polymorphism (rs71428439) is located in Homo sapiens miR-149 stem-loop region. This polymorphism results in a change in the structure of the miR-149 precursor. Our results showed that the genotype distribution of this polymorphism in myocardial infarction cases was significantly different from that in the control subjects. We examined the biological significance of this polymorphism on the production of mature miR-149, and we observed that the G-allelic miR-149 precursor displayed a lower production of mature miR-149 compared with the A-allelic one. Further investigations disclosed that miR-149 could withstand mitochondrial fission and apoptosis through targeting the pro-apoptotic factor p53-up-regulated modulator of apoptosis (Puma). Enforced expression of miR-149 promoted cell survival, whereas knockdown of miR-149 rendered cells to be sensitive to apoptotic stimulation. Intriguingly, the A to G variation led pre-miR-149 to elicit an attenuated effect on the inhibition of mitochondrial fission and apoptosis. Finally, this polymorphism exerts its influence on cardiac function in the mouse model of myocardial infarction. These data suggest that this polymorphism in the miR-149 precursor may result in important phenotypic traits of myocardial infarction. Our findings warrant further investigations on the relationship between miR-149 polymorphism and myocardial infarction.
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Semi-transparent a-IGZO thin-film transistors with polymeric gate dielectric.
J Nanosci Nanotechnol
PUBLISHED: 07-19-2013
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We report the fabrication of semi-transparent a-IGZO-based thin-film transistors (TFTs) with crosslinked poly-4-vinylphenol (PVP) gate dielectric layers on PET substrate and thermally-evaporated Al/Ag/Al source and drain (S&D) electrodes, which showed a transmittance of 64% at a 500-nm wavelength and sheet resistance of 16.8 omega/square. The semi-transparent a-IGZO TFTs with a PVP layer exhibited decent saturation mobilities (maximum approximately 5.8 cm2Ns) and on/off current ratios of approximately 10(6).
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Identification and characterization of granule bound starch synthase I (GBSSI) gene of tartary buckwheat (Fagopyrum tataricum Gaertn.).
Gene
PUBLISHED: 07-16-2013
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Tartary buckwheat (Fagopyrum tataricum Gaertn.) is increasingly considered as an important functional food material because of its rich nutraceutical compounds. Reserve starch is the major component of tartary buckwheat seed. However, the gene sequences and the molecular mechanism of tartary buckwheat starch synthesis are unknown so far. In this study, the complete genomic sequence and full-size cDNA coding tartary buckwheat granule-bound starch synthase I (FtGBSSI), which is responsible for amylose synthesis, were isolated and analyzed. The genomic sequence of the FtGBSSI contained 3947 nucleotides and was composed of 14 exons and 13 introns. The cDNA coding sequence of FtGBSSI shared 63.3%-75.1% identities with those of dicots and 56.6%-57.5% identities with monocots (Poaceae). In deduced amino acid sequence of FtGBSSI, eight motifs conserved among plant starch synthases were identified. A cleavage at the site IVC?G of FtGBSSI protein produces the chloroplast transit sequence of 78 amino acids and the mature protein of 527 amino acids. The FtGBSSI mature protein showed an identity of 73.4%-77.8% with dicot plants, and 67.6%-70.4% with monocot plants (Poaceae). The mature protein was composed of 20 ?-helixes and 16 ?-strands, and folds into two main domains, N- and C-terminal domains. The critical residues which are involved in ADP and sugar binding were predicted. These results will be useful to modulate starch composition of buckwheat kernels with the aim to produce novel improved varieties in future breeding programs.
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Positive homotropic allosteric binding of silver(I) ions in multidentate azacalixpyridine macrocycles: effect on the formation and stabilization of silver nanoparticles.
Chem. Commun. (Camb.)
PUBLISHED: 07-09-2013
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We report herein the occurrence of a positive homotropic allosteric binding effect of two macrocyclic azacalixpyridines. This effect was firstly found to be crucial in the formation and stabilization of ultra-small silver nanoparticles.
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Interferon regulatory factor 4 regulates obesity-induced inflammation through regulation of adipose tissue macrophage polarization.
Diabetes
PUBLISHED: 07-08-2013
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Interferon regulatory factors (IRFs) play functionally diverse roles in the transcriptional regulation of the immune system. We have previously shown that several IRFs are regulators of adipogenesis and that IRF4 is a critical transcriptional regulator of adipocyte lipid handling. However, the functional role of IRF4 in adipose tissue macrophages (ATMs) remains unclear, despite high expression there. Here we show that IRF4 expression is regulated in primary macrophages and in ATMs of high-fat diet-induced obese mice. Irf4(-/-) macrophages produce higher levels of proinflammatory cytokines, including interleukin-1? and tumor necrosis factor-?, in response to fatty acids. In coculture experiments, IRF4 deletion in macrophages leads to reduced insulin signaling and glucose uptake in 3T3-L1 adipocytes. To determine the macrophage-specific function of IRF4 in the context of obesity, we generated myeloid cell-specific IRF4 knockout mice, which develop significant insulin resistance on a high-fat diet, despite no difference in adiposity. This phenotype is associated with increased expression of inflammatory genes and decreased insulin signaling in adipose tissue, skeletal muscle, and liver. Furthermore, Irf4(-/-) ATMs express markers suggestive of enhanced M1 polarization. These findings indicate that IRF4 is a negative regulator of inflammation in diet-induced obesity, in part through regulation of macrophage polarization.
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Maintenance chemotherapy for ovarian cancer.
Cochrane Database Syst Rev
PUBLISHED: 07-02-2013
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Epithelial ovarian cancer accounts for about 90% of all cases of ovarian cancer. Debulking surgery and six courses of platinum-based chemotherapy results in complete clinical remission (CCR) in up to 75% of cases. However, 75% of the responders will relapse within a median time of 18 to 28 months and only 20% to 40% of women will survive beyond five years. It has been suggested that maintenance chemotherapy could assist in prolonging remission. To date, there has not been a systematic review on the impact of maintenance chemotherapy for epithelial ovarian cancer.
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[Clinical and genetic study of Wilsons disease in affected twins and siblings].
Zhonghua Yi Xue Yi Chuan Xue Za Zhi
PUBLISHED: 06-08-2013
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To study the clinical and genetic characteristics of twins and siblings affected with Wilsons disease (WD).
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The mERG1a channel modulates skeletal muscle MuRF1, but not MAFbx, expression.
Muscle Nerve
PUBLISHED: 05-28-2013
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Introduction: We investigated the mechanism by which the MERG1a K(+) channel increases ubiquitin proteasome proteolysis (UPP). Methods: Hindlimb suspension and electro-transfer of Merg1a cDNA into mouse gastrocnemius muscles induced atrophy. Results: Atrophic gastrocnemius muscles of hindlimb-suspended mice express Merg1a, Murf1, and Mafbx genes. Electrotransfer of Merg1a significantly decreases muscle fiber size (12.6%) and increases UPP E3 ligase Murf1 mRNA (2.1-fold) and protein (23.7%), but does not affect Mafbx E3 ligase expression. Neither Merg1a-induced decreased fiber size nor Merg1a-induced increased Murf1 expression is curtailed significantly by coexpression of inactive HR-Foxo3a, a gene encoding a transcription factor known to induce Mafbx expression. Conclusions: The MERG1a K(+) channel significantly increases expression of Murf1, but not Mafbx. We explored this expression pattern by expressing inactive Foxo3a and showing that it is not involved in MERG1a-mediated expression of Murf1. These findings suggest that MERG1a may not modulate Murf1 expression through the AKT/FOXO pathway. Muscle Nerve, 2013.
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Controlled arrays of self-assembled peptide nanostructures in solution and at interface.
Langmuir
PUBLISHED: 05-24-2013
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Controlling the formation of large and homogeneous arrays of bionanostructures through the self-assembly approach is still a great challenge. Here, we report the spontaneous formation of highly ordered arrays based on aligned peptide nanostructures in a solution as well as at an interface by self-assembly. By controlling the time and temperature of self-assembly in the solution, parallel fibrous alignments and more sophisticated two-dimensional "knitted" fibrous arrays could be formed from aligned rod-like fibers. During the formation of such arrays, the "disorder-to-order" transitions are controlled by the temperature-responsible motile short hydrophobic tails of the gemini-like amphiphilic peptides (GAPs) with asymmetric molecular conformation. In addition, the resulting long-range-ordered "knitted" fibrous arrays are able to direct mineralization of calcium phosphate to form organic-inorganic composite materials. In this study, the self-assembly behavior of these peptide building blocks at an interface was also studied. Highly ordered spatial arrays with vertically or horizontally aligned nanostructures such as nanofibers, microfibers, and microtubes could be formed through interfacial assembly. The regular structures and their alignments on the interface are controlled by the alkyl chain length of building blocks and the hydrophilicity/hydrophobicity property of the interface.
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Self-adjustable crystalline inorganic nanocoils.
J. Am. Chem. Soc.
PUBLISHED: 04-25-2013
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Biomacromolecules such as proteins, although extremely complex in microstructure, can crystallize into macro-sized crystals after self-adjusting their shapes, based on which the structure of biology is built. Inorganic nanowires/nanoribbons with a similar one-dimensional topology but much simpler structures can hardly be as flexible as macromolecules when constructing superlattice structures because of their inherent rigidity. Here we report the synthesis of crystalline indium sulfide nanoribbon-based nanocoils that are formed by spontaneous self-coiling of ultrathin nanoribbons. The nanostructures are flexible and appear as relatively random coils because of their ultrathin ribbon structures (~0.9 nm in thickness) with high aspect ratios. Moreover, the nanocoils can self-adjust their shapes and assemble into two-dimensional superlattices and three-dimensional supercrystals in solution. The ultrathin nanocoils are expected to bring new insights into the use of flexible nanocrystals as building blocks for constructing superstructures.
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Ultrathin nanostructures: smaller size with new phenomena.
Chem Soc Rev
PUBLISHED: 04-17-2013
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Ultrathin nanostructures possess the very essential features of nanomaterials, including quantum-confinement effects and unconventional reactivities, which are determined by the significant structure variations from the bulk material. More and more isolated reports on ultrathin nanostructures and various new phenomena have appeared in recent years but a comprehensive review on their typical features and future development has not followed. Here we aim to present a well-organized review which comments on the most important characteristics of non-carbon ultrathin nanostructures, in an attemp to reveal the underlying relationship between their reactivity, stability and transformation law, and their structures.
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Formamide: an efficient solvent to synthesize water-soluble and sub-ten-nanometer nanocrystals.
Nanoscale
PUBLISHED: 04-17-2013
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Nanocrystals have drawn lots of attention in many fields. The main-stream synthetic routes usually produced hydrophobic nanocrystals (NCs). Organometallic precursors and long-alkyl-chain ligands are adopted and for further use surface modification to render them water-soluble is needed. A direct protocol to synthesize water-soluble NCs in an environmental-friendly and convenient way is still quite deficient, especially for sub-10 nm NCs. We report here a formamide solvent-system to prepare high-quality metal, metal alloy, metal sulfide, metal selenide and ternary sulfide NCs in the sub-10 nm region, with simple inorganic metal salts as precursors. The as-obtained NCs exhibit monodisperse size and can be dispersed in aqueous solution for further applications.
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Fine tuning of the structure of Pt-Cu alloy nanocrystals by glycine-mediated sequential reduction kinetics.
Small
PUBLISHED: 04-15-2013
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Uniform Pt-Cu alloy nanocrystals in the shape of dendrite, yolk-cage, and box structures are prepared via a facile wet-chemical reduction route in which glycine is demonstrated to alter the reduction kinetics of metal cations, critical to the morphology of the obtained product. These alloy nanocrystals exhibit superior specific activity and stability in the electro-oxidation of methanol.
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Polyoxometalate-based supramolecular gel.
Sci Rep
PUBLISHED: 04-05-2013
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Self-assemblyings of surfactant-encapsulated Wells-Dawson polyoxometalates (SEPs) nanobuilding blocks in butanone and esters yielded supramolecular gels showing thermo and photo responsive properties. The gels can be further polymerized if unsaturated esters were used and subsequently electrospinned into nanowires and non-woven mats. The as-prepared non-woven mats have a Youngs modulus as high as 542.55 MPa. It is believed that this supramolecular gel is a good platform for polyoxometalates processing.
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One-pot fabrication of single-crystalline octahedral Pt-Cu nanoframes and their enhanced electrocatalytic activity.
Nanoscale
PUBLISHED: 04-03-2013
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Octahedral Pt-Cu nanoframes have been synthesized by a one-pot aqueous method. Due to the unique structure and possible synergetic effect of Pt and Cu components, these octahedral Pt-Cu nanoframes exhibited significantly enhanced catalytic activity toward the electro-oxidation of formic acid in comparison with commercial Pt black and Pt/C catalysts.
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Dynamic changes in radial oxygen loss and iron plaque formation and their effects on Cd and As accumulation in rice (Oryza sativa L.).
Environ Geochem Health
PUBLISHED: 03-26-2013
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Temporal variations and correlations between radial oxygen loss (ROL), iron (Fe) plaque formation, cadmium (Cd) and arsenic (As) accumulation were investigated in two rice cultivars at four different growth stages based upon soil pot and deoxygenated solution experiments. The results showed that there were significant differences in ROL (1.1-16 ?mol O(2) plant(-1) h(-1)), Fe plaque formation (4,097-36,056 mg kg(-1)), Cd and As in root tissues (Cd 77-162 mg kg(-1); As 49-199 mg kg(-1)) and Fe plaque (Cd 0.4-24 mg kg(-1); As 185-1,396 mg kg(-1)) between these growth stages. ROL and Fe plaque increased dramatically from tillering to ear emergence stages and then were much reduced at the grain-filling stage. Furthermore, significantly positive correlations were detected between ROL and concentrations of Fe, Cd and As in Fe plaque. Our study indicates that increased Fe plaque forms on rice roots at the ear emergence stage due to the increased ROL. This stage could therefore be an important period to limit the transfer and distribution of Cd and As in rice plants when growing in soils contaminated with these toxic elements.
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Uncommon deformation mechanisms during fatigue-crack propagation in nanocrystalline alloys.
Phys. Rev. Lett.
PUBLISHED: 03-25-2013
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The irreversible damage at cracks during the fatigue of crystalline solids is well known. Here we report on in situ high-energy x-ray evidence of reversible fatigue behavior in a nanocrystalline NiFe alloy both in the plastic zone and around the crack tip. In the plastic zone, the deformation is fully recoverable as the crack propagates, and the plastic deformation invokes reversible interactions of dislocation and twinning in the nanograins. But around the crack tip lies a regime with reversible grain lattice reorientation promoted by a change of local stress state. These observations suggest unprecedented fatigue deformation mechanisms in nanostructured systems that are not addressed theoretically.
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One-pot, template-free synthesis of Pd-Pt single-crystalline hollow cubes with enhanced catalytic activity.
Chem Asian J
PUBLISHED: 03-16-2013
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Hollow structures have attracted ever-growing interest owing to their various excellent properties. However, a facile strategy for their fabrication is still desired. Herein, Pd-Pt alloy with three different morphologies, that is, cubes, hollow cubes, and truncated octahedrons, is synthesized by using a one-pot, template-free method. The mechanism and dynamics of this system is also studied in detail. In particular, the hollow cubic structure represents enhanced catalytic activity in both coupling reactions and in the electrochemical oxidation of formic acid.
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Nanowire membrane-based nanothermite: towards processable and tunable interfacial diffusion for solid state reactions.
Sci Rep
PUBLISHED: 03-08-2013
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Interfacial diffusion is of great importance in determining the performance of solid-state reactions. For nanometer sized particles, some solid-state reactions can be triggered accidently by mechanical stress owing to their large surface-to-volume ratio compared with the bulk ones. Therefore, a great challenge is the control of interfacial diffusion for solid state reactions, especially for energetic materials. Here we demonstrate, through the example of nanowire-based thermite membrane, that the thermite solid-state reaction can be easily tuned via the introduction of low-surface-energy coating layer. Moreover, this silicon-coated thermite membrane exhibit controlled wetting behavior ranging from superhydrophilic to superhydrophobic and, simultaneously, to significantly reduce the friction sensitivity of thermite membrane. This effect enables to increase interfacial resistance by increasing the amount of coating material. Indeed, our results described here make it possible to tune the solid-state reactions through the manipulation of interfacial diffusion between the reactants.
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Human papillomavirus seroprevalence among men entering military service and seroincidence after ten years of service.
MSMR
PUBLISHED: 03-07-2013
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Vaccination against human papillomavirus (HPV) is recommended to prevent cervical cancer among women. Vaccinating men against human papillomavirus (HPV) can prevent penile, anal, and oral cancers, anogenital warts, and the transmission of HPV to their sexual partners. This study characterized HPV acquisition among male military members by evaluating both seroprevalence at entry into service and seroincidence of HPV infection after ten years of service. At entry, 29 of 200 (14.5%) male service members were positive for HPV serotypes 6, 11, 16, or 18. Of 199 initially seronegative for at least one of the four HPV serotypes, 68 (34.2%) seroconverted to one or more serotypes at ten years; more than one-third of these were seropositive for oncogenic HPV serotypes. This estimate of HPV seroprevalence among male military accessions is higher than that reported among U.S. civilian males. Vaccination to prevent genital warts and cancers resulting from HPV infection may decrease health care system burdens. Further analyses are warranted to understand the potential costs and benefits of a policy to vaccinate male service members.
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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.