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Cysteinyl-tRNA synthetase (CysRS) catalyzes the aminoacylation reaction of cysteine to its cognate tRNA

RAD51D (RAD51L3) is a member of the RAD51 gene family which plays important roles in maintaining genomic stability and preventing DNA damage. This study is aimed to investigate the associations between RAD51D polymorphisms and the hereditary susceptibility of hepatocellular carcinoma (HCC). In this study we conducted a hospital–based case‐control study including 805 cases (HCC patients) and 846 controls (nontumor patients) in Guangxi, China. A total of two Single–nucleotide polymorphisms (SNPs) rs12947947 and rs28363292 of RAD51D were selected and genotyped. Although we did not find two SNPs individually that had any significant main effect on risk of HCC, We found that the combined genotypes with 1‐2 risk genotypes were associated with significantly increased overall risk of HCC (OR = 1.462, 95% CI = 1.050‐2.036). According to the results of further stratification analysis, GT/GG genotype of rs28363292 increased HCC risk in zhuang people (OR = 3.913, 95% CI = 1.873‐8.175) and nonhepatitis B virus (HBV) infection population (OR = 1.774, 95% CI = 1.060‐2.969), the combined 1‐2 risk genotypes increased the risk of HCC in zhuang people (OR = 2.817, 95% CI = 1.532‐5.182) and non‐HBV infected population (OR = 1.567, 95% CI = 1.042‐2.358). Our results suggest that rs12947947 and rs28363292 polymorphisms may jointly contribute to the risk of HCC. Further large studies and functional studies are required to validate our findings.

The nature of the relationship between a property's selling price and its marketing time in the housing market remains an open question to date, despite almost 40 years of inquiry and hundreds of regressions conducted on various data sources. This study attempts to settle the long-standing open question by examining the issue from a new perspective. We demonstrate that the true price–TOM relationship should be nonlinear and characterized by an inverted U-shaped curve wherein the selling price increases with TOM up to a certain threshold, reflective of a positive exposure effect and decreases thereafter to reflect a negative stigma effect. This relationship is borne out in an empirical analysis using a large sample of home sales from the Hampton Roads, Virginia metropolitan area during an extended period of time. We then formulate hypotheses about the benefit of search by home sellers, which are subsequently confirmed by the empirical findings.

Micellar electrokinetic chromatography fingerprinting combined with quantification was successfully developed and applied to monitor the quality consistency of Weibizhi tablets, which is a classical compound preparation used to treat gastric ulcers. A background electrolyte composed of 57 mmol/L sodium borate, 21 mmol/L sodium dodecylsulfate and 100 mmol/L sodium hydroxide was used to separate compounds. To optimize capillary electrophoresis conditions, multivariate statistical analyses were applied. First, the most important factors influencing sample electrophoretic behavior were identified as background electrolyte concentrations. Then, a Box-Benhnken design response surface strategy using resolution index RF as an integrated response was set up to correlate factors with response. RF reflects the effective signal amount, resolution, and signal homogenization in an electropherogram, thus, it was regarded as an excellent indicator. In fingerprint assessments, simple quantified ratio fingerprint method was established for comprehensive quality discrimination of traditional Chinese medicines/herbal medicines from qualitative and quantitative perspectives, by which the quality of 27 samples from the same manufacturer were well differentiated. In addition, the fingerprint-efficacy relationship between fingerprints and antioxidant activities was established using partial least squares regression, which provided important medicinal efficacy information for quality control. The present study offered an efficient means for monitoring Weibizhi tablet quality consistency.

Problem The retarded development of fetal thymus in intrauterine growth restriction (IUGR) from maternal undernutrition during late pregnancy destroys the tridimensional structure and modifies the development of fetal T lymphocytes. The mechanisms, however, remain unclear. The objective of this study was to investigate the effect of IUGR during late pregnancy on the development of the ovine fetal thymus and the T-lymphocyte subpopulation. Method of study Eighteen time-mated ewes with singleton fetuses were allocated to three groups at day 90 of pregnancy: restricted group 1 (RG1, 0.18 MJ ME/BW0.75/day, n = 6), restricted group 2 (RG2, 0.33 MJ ME/BW0.75/day, n = 6) and a control group (CG, ad libitum, 0.67 MJ ME/BW0.75/day, n = 6). Fetuses were recovered at slaughter on day 140. Results Fetuses in RG1 exhibited decreased (P

This article studies the effect of immigrant status on mortgage delinquency. Due to their different social and economic background, immigrant households may not integrate well into the host society, and therefore are more likely to be delinquent on mortgages than otherwise identical native-born households. We test this hypothesis by comparing the mortgage delinquency rate between immigrant and native-born households in the 2009 PSID (Panel Study of Income Dynamics) data, in which all the immigrant households have been in the United States for more than 10 years. We find that, after controlling for observables, those relatively recent immigrants who have been in the United States for 10 to 20 years have a higher mortgage delinquency rate than native-born, while immigrants who have resided in the United States for more than 20 years are no different from native-borns. In addition, there is no evidence that the second generation of immigrants is more likely to be delinquent than the third-or-higher generations. Our results are robust to potential sample-selection bias and functional misspecifications.

A capillary electrophoresis fingerprint was constructed for Sanhuang tablet, a Chinese traditional patent medicine, that was commonly used in clinical practice, where the isosceles trapezoid method was first applied for the optimization of background electrolyte solution, and the resolution index was performed to assess the experimental conditions; furthermore, a novel linear quantitative fingerprint method was established for accurate qualitative and quantitative discrimination of the test samples from diverse commercial brands. The fingerprint analysis coupled with quantitative determination of two components was employed to elucidate that the quality consistency of the products was relatively good within one manufactory, but poor among different companies for the 30 batches of samples. In addition, the fingerprint–efficacy relationship between chemical components and antioxidant activity in vitro was investigated using partial least squares analysis, and the calibration and prediction of the antioxidant activity of the selected samples via fingerprint data were presented with the desired results. This work illustrates that the proposed fingerprint analysis based on linear quantitative fingerprint method can be applied for the quality evaluation of traditional Chinese medicine and herbal preparations as part of their quality control, and the constructed mathematical model is particularly suitable for depicting the fingerprint–efficacy relationship.

AimTo understand: (1) how temperature, precipitation and stand age control the above-ground biomass carbon density (BCDa) of mature forests and its macroecology patterns across latitudes; (2) the age threshold for old-growth forests at a global scale. LocationGlobal forests. MethodsWe compiled a database (897 sites) of mature forests between 80 and 1200 years old. The site data include latitude, longitude, mean annual temperature, mean annual precipitation, forest type, stand age, BCDa, living biomass (above- and below-ground biomass) carbon density and total (living plus dead) biomass carbon density. Based on the site data, we performed regression analyses to show how BCDa changes with climate and forest stand age. ResultsAt a global scale, the highest BCDa of mature forests occurred mainly in the mid-latitude regions where mean annual temperatures were 8-10 degrees C and mean annual precipitation was between 1000 and 2500mm. The average BCDa of forests in the stand age class of 450-500 years was higher than those in the other stand age classes. For forests between 80 and 450 years old, which form the majority of mature forests, carbon accumulation was faster in dead biomass than in living biomass. Main conclusionsThe highest BCDa of mature forests is located in mid-latitude regions with cool temperatures and moderate precipitation. The age threshold for old-growth forests at a global scale should be 450-500 years, which is much older than the previously documented age of 100-200 years. This older age threshold for old-growth forests is probably one of the primary reasons why recent works have concluded that old-growth forests are still carbon sinks.

Investment in thinly traded private assets involves liquidity risk. Existing literature provides limited guidance as it mainly focuses on publicly traded security assets such as stocks and bonds. This paper develops an analytical tool for quantifying liquidity risk of private assets. Using commercial real estate as a model asset and under reasonable assumptions, we find that the magnitude of liquidity risk is too large to be ignored, especially in down markets when liquidity risk is a great concern.

An indirect competitive enzyme-linked immunosorbent assay with chemiluminescent (CL-ELISA) detection for okadaic acid (OA) in mussel muscle was developed. A hybridoma cell line secreting monoclonal antibody against OA was established after immunization of BALB/c mice with artificially synthesized OA-bovine serum albumin as antigen. Luminol solution was used as the substrate for horseradish peroxidase. The detection limit was 0.175 ng/g. The range of average fortified recovery was 91.8–102.6% when OA was spiked in mussel muscle at levels of 50, 160 and 800 µg/kg. The standard curve for OA showed good linearity over the concentration range of 0.08125–20 ng/mL. The cross-reactivity with dinophysistoxin1 and saxitoxin was 51.82 and 0%, respectively. In a residue study, the results obtained by CL-ELISA correlated well within those obtained using the commercial ABRAXIS kit (ABRAXIS, Warminster, PA). The developed method is therefore suitable for detecting the residues of OA in shellfish. PRACTICAL APPLICATIONS Diarrhetic shellfish poisoning is a gastrointestinal syndrome that occurs in humans following the consumption of bivalve mollusks contaminated with OA with the main symptoms of diarrhea, nausea, vomiting and abdominal pain. OA widely exists at marine products and it is very important to develop a technique to monitor this toxin. In this study, a sensitive competitive indirect enzyme-linked immunosorbent assay with chemiluminescence for determination of OA in mussel soft tissues was investigated. Chemiluminescent ELISA (CL-ELISA) is a good alternative method for screening samples. This technique has the potential to improve the sensitivity of the immunoassays by at least two to three orders of magnitude compared with conventional colorimetric detection.

Rangeland degradation is a significant problem in the Qinghai-Tibetan Plateau, China. Restoration of the degraded rangelands through reseeding is being undermined by poor seedling growth under adverse soil moisture and nutrition conditions. Accordingly, seeds of Italian ryegrass (Lolium multiflorum) and Chinese milk vetch (Astragalus sinicus) were coated with a mixture of hygroscopic and plant-derived polysaccharide gums and alga powder (Phaeocystis sp. necolon-1), and inoculated with spores of microorganisms (Aspergillus sp. and Streptomyces sp.), serving as coating mixture decomposers, in order to improve rhizosphere moisture and nutrition. In a growth chamber simulating spring climate on the Plateau, seedling emergence of the coated seeds was 60-80 and 48-82%, respectively, for the two plant species in comparison to 38 and 24% for the uncoated seeds, which was due to moisture being supplied by the coat. In the outdoor pots with soil texture and moisture conditions similar to those of the degraded rangelands on the Plateau, dry weight of the plants from the coated seeds was 109-184 and 118-156 mg plant⁻¹ for the respective plant species, while that of the plants from uncoated seeds was 18-20 and 10-11 mg plant⁻¹. The number of Rhizobium sp. nodules on Chinese milk vetch plants from the coated seeds was 21-25 plant⁻¹ while 0-2 in plants from uncoated seeds. Enhancement of plant growth was caused by increased activity of soil microbes. Plant growth on the soil after sampling plants from the coated seeds was also enhanced, indicating sustainability of improvement of soil conditions. Thus seed coating with hygroscopic nutrient-source materials and inoculation with microorganism spores as slow decomposers of the coating materials is a promising method for restoring degraded rangelands.

The transport properties of fluid argon in rnicropores. i.e. diffusivity and viscosity. were studied by molecular dynamics simulations. The effects of pore width, temperature and density on diffusivity and viscosity were analyzed in micropores with pore widths from 0.8 to 4.0 run. The results show that the diffusivity in micropores is much lower than the bulk diffusivity, and it decreases as the pore width decreases; but the viscosity in micropores is significantly larger than the bulk one, and it increases sharply in narrow micropores. The diffusivity in channel parallel direction is obviously larger than that in channel perpendicular direction. The temperature and density are important factors that obviously affect diffusivity and viscosity in micropores.

This article develops a theoretical framework and formulates a unified risk metric that integrates both real estate price risk and uncertainty of time on market (TOM). We demonstrate that real estate sellers with different degrees of financial distress face not only different marketing period risks, but also receive different return distributions upon successful sales. The major findings of this article can be summarized as follows. First, we show that real estate return and risk, which account for both price and TOM risk, are investor specific, varying over investors with different financial circumstances and holding periods. Second, the traditional valuation of real estate return and risk, which is based solely on the return distribution of a successful sale without considering the uncertainty of TOM and the investor's financial circumstances, underestimates real estate risk and exaggerates real estate return. Third, our empirical applications in both residential and commercial real estate markets show that the Sharpe ratio estimated by the traditional approach is seriously overstated—to the largest extent for investors with high financial distress. In addition, we find that, given the typical 5- to 7-year holding period for real estate, the Sharpe ratios estimated by integrating both price and TOM risk are much in line with the performance of financial assets. These findings can help to explain the apparent “risk-premium puzzle” in real estate.

A new X-shaped π-conjugated monomer comprising of fluorene units and anthracene units was synthesized, and it was used to fabricate the new X-shaped π-conjugated polymers and investigate the properties of the new polymers. Using different molar ratios between such monomer and a fluorene monomer gave three polymers that showed higher absolute PL quantum yields than the linear polyfluorene (PF) in the solid state. After thermal annealing at 200 °C for 4 h, the linear PF showed an additional bathochromic emission at about 550 nm, whereas such red-shifted emission was fully eliminated for the X-shaped polymers. The electroluminescent devices based on the X-shaped polymers with a configuration of ITO/PEDOT:PSS/polymer/LiF/Ca/Al displayed blue emission with low turn-on voltage and high brightness.

Background Continuously renewing epithelia are maintained by stem cells that slowly proliferate and remain in the tissues for life. It has been known for decades that mouse epithelial stem cells can be selected by adherence to specific integrins. Methods The adherence of cashmere goat epidermal cells to collagen type IV for 10 min was used to obtain enriched epidermal stem cells. The characteristics of the rapidly adherent epidermal cells were determined. Results The rapidly adherent epidermal cells exhibited the stem cell characteristics of immaturity, were quiescent, showed a high colony formation efficiency, and expressed candidate surface markers for epidermal stem cells (keratin 15, keratin 19, p63, CD34, and β1-integrin). Conclusions The rapidly adherent epidermal cells represented the epidermal stem cell population.

Four new soluble polymers containing a 2,7-carbazole unit and a 2,1,3-benzothiadiazole unit in the main chain were synthesized by Suzuki polycondensation. Variation of the substituent groups (R) at 5-position of 2,1,3-benzothiadiazole unit resulted in different color emission of the copolymers. Thus, when R was CH3 (or H), the polymer showed yellow–green (or red) emission; whereas the polymers showed the emission from green to yellow–green, when R was CH2(CH2)5CH3 or CH2OCH(CH3)2. To investigate the nature of the color change, a Gaussian 03 program was used for estimation of the dihedral angles between a 5-R-2,1,3-benzothiadiazole unit and a 2,7-carbazole unit. The results showed that the different substituents at 5-position of 2,1,3-benzothiadiazole brought about different the dihedral angles, which gave the different conjugation levels to the polymers. Hence, the tunablity of emission color may be attributed to the different conjugation levels between 2,7-carbazole units and 5-R-2,1,3-benzothiadiazole units induced by simply changing substituent groups at 5-position of benzothiadiazole unit. Electrochemically, the copolymers exhibited a higher oxidation potential as well as the reversible reduction behavior bearing from 2,1,3-benzothiadiazole unit. To investigate the electroluminescent properties of the polymers, the nonoptimized devices were fabricated and the results showed that the electroluminescent emission wavelength was basically similar to that of the photoluminescent. All polymers showed good thermal stability with 5 wt % loss temperature of more than 296 °C. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1376–1387, 2008

Differential in-gel electrophoresis (DIGE) experiments allow three protein samples to be run per gel. The three samples are labeled with the spectrally resolvable fluorescent dyes, Cy2, Cy3, and Cy5, respectively. Here, we show that protein-specific dye effects exist, and we present a linear mixed model for analysis of DIGE data which takes dye effects into account. A Java implementation of the model, called DIGEanalyzer, is freely available at http://bioinfo.thep.lu.se/digeanalyzer.html. Three DIGE experiments from our laboratory, with 173, 64, and 24 gels, respectively, were used to quantify and verify the dye effects. DeCyder 5.0 and 6.5 were used for spot detection and matching. The fractions of proteins with a statistically significant (0.001 level) dye effect were 19, 34, and 23%, respectively. The fractions of proteins with a dye effect above 1.4-fold change were 1, 4, and 6%, respectively. The median magnitude of the dye effect was 1.07-fold change for Cy5 versus Cy3 and 1.16-fold change for Cy3 versus Cy2. The maximal dye effect was a seven-fold change. The dye effects of spots corresponding to the same protein tend to be similar within each of the three experiments, and to a smaller degree across experiments.

Starch was crosslinked with poly(vinyl alcohol) (PVA) by boric acid. A suitable plasticizer and defoamer were added to obtain the brei. A film from the starch and PVA (SP film) was prepared by casting. The effects of various factors, such as the crosslinking temperature, the PVA content, and the amounts of glycerol and boric acid, on the tensile strength and breaking elongation were studied. The results showed that the SP film prepared by boric acid crosslinking had excellent mechanical properties. The film-forming properties, transmittance, and water resistance of the SP film were also investigated. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1394–1397, 2005

Peptides with an exposed arginine-glycine-aspartate (Arg-Gly-Asp, RGD) sequence targeting the integrin αV β3 play an important role in targeted anticancer drug delivery. The interaction of multiple RGD-containing peptides and two αV β3 molecules was studied via MD simulation. Results revealed that not all six RGD-containing peptides interact with αV β3 and interaction strengths differed among the peptides. The specific identification sites included the guanidine group of the ARG residue in the RGD peptide and the carboxyl group of the ASP residue in integrin αV β3 . Therefore, formation of a salt bridge between ARGRGD and the ASP residue was the main mechanism of interaction. H-bonds also played an important role in the observed interaction. The interaction between RGD-containing peptides and αV β3 was influenced by two factors: the relative orientation and distance between these groups. The RGD cluster, which could markedly increase the number of absorbed RGD monomers and enhance the cellular uptake of nano-medicines, was observed in this system.

The metallate, PPN+Cr(CO)4NO−, was used for the 1,3-debrominative reductive cyclization of the (±) and meso isomers of dimethyl 2,4-dibromoglutarate and dimethyl 2,4-dibromo-2,4-dimethylglutarate. In both (±) isomers, the reaction is stereospecific in giving the trans cyclopropane product. In the meso case, the reaction is unselective in the first case, but distinctly favors the cis cyclopropane isomer in the second set of compounds. This (±) and meso pair thus represent the first example of near stereospecificity in the debrominations of both 1,3-dibromo diastereomers. Using an enantiomerically enriched dimethyl 2,4-dibromoglutarate, and determining the absolute stereochemistry of the cyclopropane product, it was found that a strict double inversion mechanism is involved in the (±) debromination reaction and presumably also in the near-stereospecific meso case reported above.

A range of α-oxo ketene dithioacetals 1 reacted with Vilsmeier reagent (POCl 3 /DMF) to afford α-chlorovinyl ketene dithioacetals 2. With the treatment of NaOH in ethanol or methanol, the compounds 2 were transformed into the corresponding α-ethynyl ketene dithioacetals 3 in moderate to high yields.