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Halesia (Styracaceae) has been considered to comprise three species, two from the eastern United States (H. carolina, H. diptera), and one from China (H. macgregorii). In a prior phylogenetic study of the Styracaceae, analysis of morphological data yielded a clade comprising the three species whereas molecular data (nuclear ITS and plastid rbcL and trnL-trnF) yielded a placement of H. macgregorii as sister to Rehderodendron, with the two North American species of Halesia placed outside of this clade. We further investigated the phylogenetic placement of H. macgregorii relative to other genera in the family with an expanded molecular data set. The results corroborate prior analyses placing H. macgregorii with Rehderodendron rather than with the North American species of Halesia. On this basis, combined with an assessment of morphological character variation among H. macgregorii, the other (North American) species of Halesia, and Rehderodendron, we erect Perkinsiodendron as a new genus in the Styracaceae to accommodate H. macgregorii and form the new combination P. macgregorii. We also provide a lectotype for the species. This change has implications for biogeographical analyses based on generic circumscriptions. [ABSTRACT FROM AUTHOR]

In the present work, for the first time, we report the growth of hierarchical assemblies of Si3N4 nanostructures via catalyst-assisted pyrolysis of a polymeric precursor on the Si substrates. The synthesized products were characterized by using field emission scanning electron microscopy, X-ray diffraction, and transmission electron microscopy. It is found that the size of the catalytic droplet plays a critical role on the formation of hierarchical assemblies of Si3N4 nanostructures rather than common single nanowire. A mechanism based on the Vapor-Liquid-Solid (VLS) process was proposed for the assembly of hierarchical Si3N4 nanostructures. [ABSTRACT FROM AUTHOR]

Grown nucleated particles > 50 nm in diameter are an important source of cloud condensation nuclei (CCN) and when the size is > 100 nm, they can also have direct influence on the climate. In this study, the nucleation and growth of new particles in the atmosphere in Hong Kong were investigated during dry season (monthly averaged RH < 75%). The maximum size of grown nucleated particles was generally less than 40 nm during new particle burst and growth events. The exception, accounting for ∼ 20% of all burst and growth events, was those induced by strong photochemical reactions, in which subsequent particle shrinkage occurred. Temporal particle and gas concentration variability and meteorological conditions support the occurrence of particle shrinkage. The shrinkage rate calculated (∼ 8 nm h-1) was close to the growth rate. The observation of particle shrinkage sheds new light on particle transformation dynamics and it would add to the understanding of particle behavior in the atmosphere. [ABSTRACT FROM AUTHOR]

The article presents information on Akebia, which is considered a potential new fruit crop in China. The Akebia Decne is a member of the Lardizabalaceae family of flowering plants, which consists of about nine genera and 50 species. Vegetative and floral characteristics of Akebia species are also discussed, including their compound leaves comprising of three to five leaflets. Also described are traits of the fruit of Akebia, with special emphasis on size, weight, shape and color.

• Polymorphic simple sequence repeat (SSR) markers were used to investigate the impact of habitat fragmentation on the population structure and gene flow of Changiostyrax dolichocarpa, a critically endangered tree in central China. • Intrapopulation genetic diversity, population structure and gene flow in the five extant populations of this species were analysed by eight SSR markers. • Intrapopulation genetic diversity results suggest that C. dolichocarpa remnants maintained a relatively high degree of genetic diversity despite severe fragmentation. Low genetic differentiation among populations was found based on Wright's FST andamova analysis. Both the FST-based estimate and private allele method revealed high historical gene flow among the remnant populations. Recent immigrants, detected by assignment tests, tend to decrease from the grandparent generation to the current generation. • The potentially highly restricted current gene flow among fragments may render the fragmented populations of C. dolichocarpa at a higher risk of local extinction several generations after fragmentation. Both in situ and ex situ conservation management for the remnant populations of C. dolichocarpa are therefore urgently needed to rescue remaining genetic diversity. [ABSTRACT FROM AUTHOR]

Twenty-four polymorphic microsatellite loci were isolated and characterized from an AAG-enriched genomic library of Sinojackia xylocarpa. The average allele number of these microsatellites was 3.3 per locus, ranging from two to seven. The observed and expected heterozygosities at population level were 0.10–0.83 and 0.10–1.00, respectively. In addition, successful cross-species amplification of this set of microsatellites in three other species of Sinojackia and a closely related taxon, Changiostyrax dolichocarpa, suggested that this set of microsatellite markers should provide a useful tool for genetic and conservation studies of Sinojackia species and other closely related taxa in the Styracaceae. [ABSTRACT FROM AUTHOR]

This paper presents a technique to study air pollution by combining high spatial resolution data obtained by a mobile platform and those measured by conventional stationary stations. Conventional stations provide time-series point data but cannot yield information that is distant from the sites. This can be complemented or supplemented by mobile measurements in the vicinity of the conventional sites. Together, the combined dataset yields a clearer and more precise picture of the dispersion and the transformation of pollutants in the atmosphere in a fixed time frame. Several experiments were conducted in the years 2002-2003 to track the impact of power plant plumes on ground receptors in the immediate vicinity (within a radius of 30 km) of the plants, using a combined mobile and stationary dataset. The mobile data allowed the identification of emissions from coal-fired and gas- fired power plants. Coal-fired power plants were the major source of sulfur dioxide (SO2), whereas nitrogen oxides (NOx) emitted from the gas-fired power plant played an important role in the formation of ozone (O3) at ground level. The mobile data showed that two particle size distribution regimes were detected: one had a dominant accumulation mode at 0.40-0.65 µm and the other at 0.65-1 µm. The existence of particles characterized by their mode at 0.65-1 µm and formed by in-cloud processes suggests that vehicular emissions were not the important source. Other local sources, such as power plants (elevated emission), were the likely sources, because Hong Kong does not have much manufacturing industry. [ABSTRACT FROM AUTHOR]

Although sampling artifacts of acidity, ammonium, nitrate, and chloride in airborne particulate pollutants can be reduced by the use of denuders to absorb interfering gases, artifacts due to interparticle interactions still remain. In this study, the contribution of individual artifact reactions to particle evaporation and the effects of aerosol composition on the extents of sampling artifacts in PM[SUB2.5] were investigated. Samples were collected using a Harvard honeycomb denuder/filter-pack system at an urban site and a rural site in Hong Kong. The results show that the formation of artifacts can be categorized into two regimes: ammonium rich (AR) samples with a molar ratio [NH[SUB4][SUP+]]/[SO[SUB4][SUP2-]] greater than 1.5 and ammonium poor (AP) samples with a molar ratio [NH[SUB4][SUP+]]/[SO[SUB4][SUP2-] less than or equal to 1.5. The urban samples were all AR samples, and they were characterized by high nitrate and low in situ free acid concentrations. In contrast, the rural samples were all AP samples and they were characterized by low nitrate and high in situ free acid concentrations. We have developed a methodology to estimate the contribution of each artifact reaction to the sampling loss of nitrate, chloride, ammonium, and acidity. In the AR samples, the evaporation of HNO[SUB3] and HCl and concomitant evaporation of NH[SUB3] were the principal reactions in determining the extent of the sampling loss of nitrate and chloride. In the AP samples, the evaporation of HNO[SUB3] and HCl alone was the principal reaction instead, especially at high sampling loss. The in situ free acid concentration, a function of aerosol composition and ambient conditions, is a more useful parameter than strong acidity in understanding the sampling loss of acidity, nitrate, and chloride from the collected particles. [ABSTRACT FROM AUTHOR]

The PM2.5 concentrations and the size distributions of dicarboxylic acids in Hong Kong were studied. Eleven sets of daily PM2.5 samples were obtained at a downtown sampling site during the period of 5-16 December 2000 using an R&P speciation PM2.5 sampler. About 6-12% of the total oxalic acid was found in the gas phase in some samples. A good correlation between succinate and sulfate (R² = 0.88) and a moderate correlation between oxalate and sulfate (R² = 0.74) were found. Sampling artifacts of oxalate, malonate and succinate were found to be negligible. A total of 18 sets of 48-96 h size distribution data on dicarboxylic acids, sulfate, nitrate and sodium at an urban site and a rural site from June 2000 to May 2001 were obtained using a Micro-Orifice Uniform Deposit Impactor. Data from both sites show similar size distribution characteristics of the dicarboxylic acids. The condensation mode of oxalate was usually observed at 0.177-0.32 µm. The location of the peak of the droplet mode of oxalate was associated with that of sulfate. When the peak of sulfate in the droplet mode appeared at 0.32-0.54 µm, the peak of oxalate sometimes appeared at 0.32-0).54gm and sometimes shifted to 0.54-1.0 µm. When the peak of sulfate in the droplet mode appeared at 0.54-1.0 µm, the peak of oxalate sometimes appeared at 0.54-1.0 µm and sometimes shifted to 1.0-1.8 µm. Oxalate, succinate and sulfate found in the droplet mode were attributed to in-cloud formation. The slight shift of the oxalate peak from 0.32-0.54 to 0.54-1.0 µm or from 0.54-1.0 to 1.0-1.8 µm was ascribed to minor oxalate evaporation after incloud formation. The maximum peak of malonate sometimes appeared in the droplet mode and sometimes appeared at 3.1-6.2 µm. The formation of malonate is associated to the reactions between sea salt and malonic acid. . [ABSTRACT FROM AUTHOR]

Focuses on the use of generalized logistic model of individual tree mortality for trembling aspen, white spruce and lodgepole pine. Determination on the survival probability of an individual tree; Stand characteristics of trees; Estimation of species-specific site productivity index.

Performs an experimental study of the sampling artifact of chloride (Cl) depletion from collected sea salt aerosols. Possibility of Cl depletion as a result of particle-particle interactions in sampling; Size dependence of Cl depletion; Factors affecting depletion rate.

Spermatogonial stem cells (SSCs) are essential for continuous spermatogenesis and male fertility. The underlying mechanisms of alternative splicing (AS) in mouse SSCs are still largely unclear. We demonstrated that SRSF1 is essential for gene expression and splicing in mouse SSCs. Crosslinking immunoprecipitation and sequencing data revealed that spermatogonia-related genes (e.g. Plzf, Id4, Setdb1, Stra8, Tial1/Tiar, Bcas2, Ddx5, Srsf10, Uhrf1, and Bud31) were bound by SRSF1 in the mouse testes. Specific deletion of Srsf1 in mouse germ cells impairs homing of precursor SSCs leading to male infertility. Whole-mount staining data showed the absence of germ cells in the testes of adult conditional knockout (cKO) mice, which indicates Sertoli cell-only syndrome in cKO mice. The expression of spermatogonia-related genes (e.g. Gfra1, Pou5f1, Plzf, Dnd1, Stra8, and Taf4b) was significantly reduced in the testes of cKO mice. Moreover, multiomics analysis suggests that SRSF1 may affect survival of spermatogonia by directly binding and regulating Tial1/Tiar expression through AS. In addition, immunoprecipitation mass spectrometry and co-immunoprecipitation data showed that SRSF1 interacts with RNA splicing-related proteins (e.g. SART1, RBM15, and SRSF10). Collectively, our data reveal the critical role of SRSF1 in spermatogonia survival, which may provide a framework to elucidate the molecular mechanisms of the posttranscriptional network underlying homing of precursor SSCs. [ABSTRACT FROM AUTHOR]

In this article the authors discuss aspects of the report "Atmospheric Particulate Matter Pollution During the 2008 Beijing Olympics" within the issue. They are critical of the quartz filter-based gravimetric method used by researchers to measure mass concentrations of particulate matter (PM) and suggest that its use was inappropriate. The authors reference a method for the determination of PM in the atmosphere which they feel should have been used by the researchers.

Background and Aims The genus Sinojackia consists of eight species, all endemic to China. All species of Sinojackia are endangered or threatened owing to poor recruitment within populations. Information on molecular phylogenetics is critical for developing successful conservation strategies for this genus. Methods Combined DNA sequence data from the nuclear ribosomal internal transcribed spacer regions and plastid psbA–trnH intergenic spacer and microsatellite data were used to infer a phylogeny of the genus. Key Results Parsimony analysis of the combined sequence data and multivariate analysis based on fruit characters indicated that Sinojackia dolichocarpa is monophyletic and genetically well separated from the other Sinojackia species, thus supporting its rank at the generic level as Changiostyrax. Phylogenetic relationships within Sinojackia sensu stricto are unresolved from the combined sequence data. A UPGMA dendrogram based on seven microsatellite loci of 96 individual plants yielded a first-diverging cluster of all individuals of S. microcarpa. The remaining species form another cluster without any definitive patterns corresponding to current species circumscriptions, suggesting either extensive hybridization or incipient speciation. Conclusions The results suggest that there are too many species recognized within Sinojackia sensu stricto, but this must be further assessed with comprehensive morphological and taxonomic revisionary work. The implications of the phylogenetic data for conservation are discussed. [ABSTRACT FROM AUTHOR]

This study explores the application of wavelet decomposition as a means to distinguish between local and regional sources of ultrafine particles (UFP). Particle number concentrations were measured at a central site, two downtown sites, and four residential sites located across Toronto, Canada. Using a wavelet decomposition algorithm, particle concentration time series were separated into two signals: high frequency local-to-neighbourhood scale sources and low frequency urban-to-regional scale sources and processes. At the field sites, local-neighbourhood sources contributed between 13 and 32% of the total particle concentration. The urban-regional signal at each field site exhibited stronger correlation and greater homogeneity with respect to the central site than the original concentration time series. In contrast, the high frequency local-neighbourhood source signals exhibited limited correlation and high heterogeneity with respect to the central site. Traffic volume within a 2.5 km buffer explained 87% of the variability in the local-neighbourhood level signal observed between field sites while no significant association with traffic was found for the original particle number concentration data. This study has demonstrated that wavelet decomposition can be a useful tool for estimating exposure to UFP from local-neighbourhood and urban-regional scale sources and processes. [ABSTRACT FROM AUTHOR]

Psilopeganum sinense is a perennial herb endemic to Three-Gorges Reservoir Area (TGRA) in China. Genetic diversity of this endangered species was assessed by using 11 nuclear microsatellites and three chloroplast microsatellite (cpSSR) markers. A total of 8 haplotypes were identified in a survey of 212 individuals sampled from nine populations encompassing most of the natural range of the species. A low level of genetic diversity was detected: HE = 0.301 for SSR and HE = 0.28 for cpSSR. Populations were highly differentiated from one another: an AMOVA analysis that showed that 56.3% and 68.2% genetic variation resided between populations based on SSR and cpSSR analysis, respectively, and FST and FSTc (0.467 for SSR and 0.644 for cpSSR, respectively) were high. Significant differences were found between estimates of haplotypic differentiation calculated by using unordered alleles (GSTc = 0.857) and ordered alleles (NSTc = 0.728), which indicated the existence of phylogeographical structure in P. sinense. The indirect ratio of pollen flow/seed flow derived from estimates of haplotypic and nuclear DNA differentiation indicated that gene flow via pollen is less efficient than via seed. Two distinct evolutionary lineages (evolutionary significant units, ESUs) were recognized for P. sinense on the basis of both the PCoA and NCA analysis. Sampling strategies for conserving this endangered plant were discussed. [ABSTRACT FROM AUTHOR]

China has adopted nuclear power generation as one of the strategic energy sources to resolve the dilemma between its ever-growing energy demand and the associated environmental issues. To achieve the latter, a systematic assessment of the state of the ecosystem near nuclear power plants and its restoration via ongoing recovery actions would be highly desirable and much needed. Current assessment methods are mostly based on the individual components of the ecosystem and the methods are therefore not integrated. In this paper, we report a set of system-based assessment indices to study the restoration of Daya Bay in Guangdong, China where a nuclear power plant has been in operation for 15 years. The results show that decades of intensive exploitation by the various coastal activities have pushed Daya Bay's ecosystem away from its baseline and its structure and functions are impaired; ecosystem restoration does not make up for the weakening of the ecological carrying capacity due to anthropogenic sea-use, nonetheless, the potential for recovery still exists. The case study suggests that the system-based indices can provide integrated information for ecosystem restoration assessment and management. [ABSTRACT FROM AUTHOR]

Nine polymorphic microsatellite loci were isolated and characterized from an AC-enriched genomic library of Disanthus cercidifolius var. longipes. Microsatellite polymorphism was investigated using 24 individuals from one natural population. The observed number of alleles per locus ranged from two to four. Observed and expected heterozygosities ranged from 0.17 to 0.92 and from 0.16 to 0.72, respectively. These polymorphic microsatellite loci provide useful tools for the ongoing population genetic studies of D. cercidifolius var. longipes. [ABSTRACT FROM AUTHOR]

Twenty-nine primer pairs flanking microsatellite repeats were designed from an AC-enriched genomic library of Psilopeganum sinense and tested using 24 individuals derived from a natural population. A total of 11 microsatellite loci were found polymorphic. The number of alleles per locus varied from two to eight, with an average value of 3.7. The ranges of observed and expected heterozygosities were 0.000–0.750 and 0.365–0.800, respectively. These microsatellite loci have been directly applied to the ongoing conservation genetic studies of P. sinense. [ABSTRACT FROM AUTHOR]

Arsenic is a toxic pollutant commonly found in the environment. Most of the previous studies on arsenic pollution have primarily focused on arsenic contamination in groundwater. In this study, we examine the impact on human health from atmospheric arsenic on the global scale. We first develop an improved global atmospheric arsenic emission inventory and connect it to a global model (Goddard Earth Observing System [GEOS]-Chem). Model evaluation using observational data from a variety of sources shows the model successfully reproduces the spatial distribution of atmospheric arsenic around the world. We found that for 2005, the highest airborne arsenic concentrations were found over Chile and eastern China, with mean values of 8.34 and 5.63 ng/m², respectively. By 2015, the average atmospheric arsenic concentration in India (4.57 ng/m²) surpassed that in eastern China (4.38 ng/m²) due to the fast increase in coal burning in India. Our calculation shows that China has the largest population affected by cancer risk due to atmospheric arsenic inhalation in 2005, which is again surpassed by India in 2015. Based on potential exceedance of health-based limits, we find that the combined effect by including both atmospheric and groundwater arsenic may significantly enhance the risks, due to carcinogenic and noncarcinogenic effects. Therefore, this study clearly implies the necessity in accounting for both atmospheric and groundwater arsenic in future management. [ABSTRACT FROM AUTHOR]

Water soluble inorganic ions such as ammonium, nitrate, and sulfate are major components of fine aerosols in the atmosphere and are widely used in the estimation of aerosol acidity. However, different experimental practices and instrumentation may lead to uncertainties in ion concentrations. Here, an inter-comparison experiment was conducted in 10 different laboratories (labs) to investigate the consistency of inorganic ion concentrations and resultant aerosol acidity estimates using the same set of aerosol filter samples. The results mostly exhibited good agreement for major ions Cl-, SO42-, NO3-, NH4+ and K+. However, F-, Mg2+ and Ca2+ were observed with more variations across the different labs. The Aerosol Chemical Speciation Monitor (ACSM) data of non-refractory SO42-, NO3-, NH4+ generally correlated very well with the filter analysis based data in our study, but the absolute concentrations differ by up to 42 %. Cl- from the two methods are correlated but the concentration differ by more than 3 times. The analyses of certified reference materials (CRMs) generally showed good recovery of all ions in all the labs, the majority of which ranged between 90 % and 110 %. Better agreements were found for Cl-, SO42-, NO3-, NH4+ and K+ across the labs after their concentrations were corrected with CRM recoveries; the coefficient of variation (CV) of Cl-, SO42-, NO3-, NH4+ and K+ decreased 1.7 %, 3.4 %, 3.4 %, 1.2 % and 2.6 %, respectively, after CRM correction. We found that the ratio of anion to cation equivalent concentrations (AE/CE) is not a good indicator for aerosol acidity estimates, as the results in different labs did not agree well with each other. Ion balance (anions - cations) calculated from SO42-, NO3- and NH4+ gave more consistent results, because of their relatively large concentrations and good agreement among different labs. In situ aerosol pH calculated from the ISORROPIA-II thermodynamic equilibrium model with measured ion and ammonia concentrations showed a similar trend and good agreement across the 10 labs. Our results indicate that although there are important uncertainties in aerosol ion concentration measurements, the estimated aerosol pH from the ISORROPIA-II model is more consistent. [ABSTRACT FROM AUTHOR]

Objective: Glioblastoma (GBM) is the most common primary malignant brain tumor regulated by numerous genes, with poor survival outcomes and unsatisfactory response to therapy. Therefore, a robust, multi-gene signature-derived model is required to predict the prognosis and treatment response in GBM. Methods: Gene expression data of GBM from TCGA and GEO datasets were used to identify differentially expressed genes (DEGs) through DESeq2 or LIMMA methods. The DEGs were then overlapped and used for survival analysis by univariate and multivariate COX regression. Based on the gene signature of multiple survival-associated DEGs, a risk score model was established, and its prognostic and predictive role was estimated through Kaplan-Meier analysis and log-rank test. Gene set enrichment analysis (GSEA) was conducted to explore high-risk score-associated pathways. Western blot was used for protein detection. Results: Four survival-associated DEGs of GBM were identified: OSMR, HOXC10, SCARA3, and SLC39A10. The four-gene signature-derived risk score was higher in GBM than in normal brain tissues. GBM patients with a high-risk score had poor survival outcomes. The high-risk group treated with temozolomide chemotherapy or radiotherapy survived for a shorter duration than the low-risk group. GSEA showed that the high-risk score was enriched with pathways such as vasculature development and cell adhesion. Western blot confirmed that the proteins of these four genes were differentially expressed in GBM cells. Conclusions: The four-gene signature-derived risk score functions well in predicting the prognosis and treatment response in GBM and will be useful for guiding therapeutic strategies for GBM patients. [ABSTRACT FROM AUTHOR]

Commensal bacteria are critical for physiological functions in the gut, and dysbiosis in the gut may cause diseases. In this article, we report that mice deficient in cathelin-related antimicrobial peptide (CRAMP) were defective in the development of colon mucosa and highly sensitive to dextran sulfate sodium (DSS)-elicited colitis, as well as azoxymethane-mediated carcinogenesis. Pretreatment of CRAMP-/- mice with antibiotics markedly reduced the severity of DSS-induced colitis, suggesting CRAMP as a limiting factor on dysbiosis in the colon. This was supported by observations that wild-type (WT) mice cohoused with CRAMP-/- mice became highly sensitive to DSS-induced colitis, and the composition of fecal microbiota was skewed by CRAMP deficiency. In particular, several bacterial species that are typically found in oral microbiota, such as Mogibacterium neglectum, Desulfovibrio piger, and Desulfomicrobium orale, were increased in feces of CRAMP-/- mice and were transferred to WT mice during cohousing. When littermates of CRAMP+/- parents were examined, the composition of the fecal microbiota of WT pups and heterozygous parents was similar. In contrast, although the difference in fecal microbiota between CRAMP-/- and WT pups was small early on after weaning and single mouse housing, there was an increasing divergence with prolonged single housing. These results indicate that CRAMP is critical in maintaining colon microbiota balance and supports mucosal homeostasis, antiinflammatory responses, and protection from carcinogenesis. [ABSTRACT FROM AUTHOR]

To assess the relative contributions of traffic emission and other potential sources to high levels of atmospheric ammonia (NH3) in urban areas in the wintertime, atmospheric NH3 and related pollutants were measured at an urban site, ~300 m from a major traffic road, in northern China in November and December 2015. Hourly average NH3 varied from 0.3 to 10.8 ppb with an average of 2.4 ppb during the campaign. Contrary to the common perspective in literature, traffic emission was demonstrated to be a negligible contributor to atmospheric NH3. Atmospheric NH3 correlated well with ambient water vapor during many time periods lasting from tens of hours to several days, implying NH3 released from water evaporation is an important source. Emissions from local green space inside the urban areas were identified to significantly contribute to the observed atmospheric NH3 during ~60% of the sampling times. Evaporation of predeposited NHx through wet precipitation combined with emissions from local green space likely caused the spikes of atmospheric NH3 mostly occurring 1-4 h after morning rush hours or after and during slight shower events. There are still ~30% of the data samples with appreciable NH3 level for which major contributors are yet to be identified. [ABSTRACT FROM AUTHOR]

Background and Aims: The phylogeography of plant species in sub-tropical China remains largely unclear. This study used Tapiscia sinensis, an endemic and endangered tree species widely but disjunctly distributed in sub-tropical China, as a model to reveal the patterns of genetic diversity and phylogeographical history of Tertiary relict plant species in this region. The implications of the results are discussed in relation to its conservation management. Methods: Samples were taken from 24 populations covering the natural geographical distribution of T. sinensis. Genetic structure was investigated by analysis of molecular variance (AMOVA) and spatial analysis of molecular variance (SAMOVA). Phylogenetic relationships among haplotypes were constructed with maximum parsimony and haplotype network Methods. Historical population expansion events were tested with pairwise mismatch distribution analysis and neutrality tests. Species potential range was deduced by ecological niche modelling (ENM). Key Results: A low level of genetic diversity was detected at the population level. A high level of genetic differentiation and a significant phylogeographical structure were revealed. The mean divergence time of the haplotypes was approx. 1·33 million years ago. Recent range expansion in this species is suggested by a star-like haplotype network and by the results from the mismatch distribution analysis and neutrality tests. Conclusions: Climatic oscillations during the Pleistocene have had pronounced effects on the extant distribution of Tapiscia relative to the Last Glacial Maximum (LGM). Spatial patterns of molecular variation and ENM suggest that T. sinensis may have retreated in south-western and central China and colonized eastern China prior to the LGM. Multiple montane refugia for T. sinense existing during the LGM are inferred in central and western China. The populations adjacent to or within these refugia of T. sinense should be given high priority in the development of conservation policies and management strategies for this endangered species. [ABSTRACT FROM AUTHOR]

To determine the influence of red yeast rice on production performance, egg quality and serum traits of laying hens, 288 laying hens (40-week-old) were randomly assigned into four groups with 6 replications of 12 birds each. Hens were provided with diets containing 0, 0.5, 1 and 5 g/kg red yeast rice for 8- weeks. Results showed that dietary supplementation of red yeast rice had no effect (P>0.05) on laying performance over the entire feeding period. Albumen height (quadratic, cubic, P<0.05) and Haugh units (quadratic, P<0.05) were increased with gradient addition of red yeast rice. Moreover, albumen height and Haugh units were higher (P<0.05) in 1 and 5 g/kg red yeast rice groups, with an exception of albumen height in 1 g/kg group at day 28. Yolk cholesterol content was lower (P<0.05) in 5 g/kg red yeast rice-supplemented group at day 56. There were decreased (P<0.05) contents of serum cholesterol and triglyceride, but higher (P<0.05) concentration of serum calcium in the 1 and 5 g/kg red yeast rice-treated hens compared with the control group. Serum level of very-low-density lipoprotein was also reduced (P<0.05) in 5 g/kg red yeast rice-treated hens. The results suggest that red yeast rice could lower serum and egg yolk cholesterol levels and improve the egg quality in laying hens. [ABSTRACT FROM AUTHOR]

Particles larger than 50-100 nm in diameter have been considered to be effective cloud condensation nuclei (CCN) under typical atmospheric conditions. We studied the growth of newly formed particles (NPO) in the atmosphere and the conditions for these particles to grow beyond 50 nm at a suburban coastal site in Hong Kong. Altogether, 17 new particle formation events each lasting over 1 h were observed in 17 days during 8 Mar-28 Apr and 1 Nov-30 Dec 2011. In 12 events, single-stage growth of NPO was observed in daytime when the median mobility diameter of NPO (Dp) increased up to ∼40 nm but did not increase further. In three events, two-stage particle growth to 61-97 nm was observed at nighttime. The second stage growth was preceded by a first-stage growth in daytime when the Dp reached 43 ± 4 nm. In all these 15 events, organics and sulfuric acid were major contributors to the first-stage growth in daytime. Ammonium nitrate unlikely contributed to the growth in daytime, but it was correlated with the second-stage growth of ∼40 nm NPO to CCN sizes at nighttime. The remaining two events apparently showed second-stage growth in late afternoon but were confirmed to be due to mixing of NPO with pre-existing particles. We conclude that daytime NPO growth cannot reach CCN sizes at our site, but nighttime NPO growth driven by organics and NH4NO3 can. [ABSTRACT FROM AUTHOR]

The oxidation of SO2 is commonly regarded as a major driver for new particle formation (NPF) in the atmosphere. In this study, we explored the connection between measured mixing ratio of SO2 and observed long-term (duration > 3 hr) and short-term (duration < 1.5 hr) NPF events at a semi-urban site in Toronto. Apparent NPF rates (J30) showed a moderate correlation with the concentration of sulfuric acid ([H2SO4]) calculated from the measured mixing ratio of SO2 in long-term NPF events and some short-term NPF events (Category I) (R² = 0.66). The exponent in the fitting line of J30 ~ [H2SO4]n in these events was 1.6. It was also found that SO2 mixing ratios varied a lot during long-term NPF events, leading to a significant variation of new particle counts. In the SO2-unexplained short-term NPF events (Category II), analysis showed that new particles were formed aloft and then mixed down to the ground level. Further calculation results showed that sulfuric acid oxidized from SO2 probably made a negligible contribution to the growth of > 10 nm new particles. [ABSTRACT FROM AUTHOR]

Marine aerosols over the East China Seas are heavily polluted by continental sources. During the Chinese Comprehensive Ocean Experiment in November 2012, size and mass spectra of individual atmospheric particles in the size range from 0.2 to 2.0 μm were measured on board by a single particle aerosol mass spectrometer (SPAMS). The average hourly particle number (PN) was around 4560 ± 3240 in the South Yellow Sea (SYS), 2900 ± 3970 in the North Yellow Sea (NYS), and 1700 ± 2220 in the Bohai Sea (BS). PN in NYS and BS varied greatly over 3 orders of magnitude, while that in SYS varied slightly. The size distributions were fitted with two log-normal modes. Accumulation mode dominated in NYS and BS, especially during episodic periods. Coarse mode particles played an important role in SYS. Particles were classified using an adaptive resonance theory based neural network algorithm (ART-2a). Six particle types were identified with secondary-containing, aged sea-salt, soot-like, biomass burning, fresh sea-salt, and lead-containing particles accounting for 32%, 21%, 18%, 16%, 4%, and 3% of total PN, respectively. Aerosols in BS were relatively enriched in particles from anthropogenic sources compared to SYS, probably due to emissions from more developed upwind regions and indicating stronger influence of continental outflow on marine environment. Variation of source types depended mainly on origins of transported air masses. This study examined rapid changes in PN, size distribution and source types of fine particles in marine atmospheres. It also demonstrated the effectiveness of high-time-resolution source apportionment by ART-2a. [ABSTRACT FROM AUTHOR]

Chemoattractant receptors are a family of seven transmembrane G protein coupled receptors (GPCRs) initially found to mediate the chemotaxis and activation of immune cells. During the past decades, the functions of these GPCRs have been discovered to not only regulate leukocyte trafficking and promote immune responses, but also play important roles in homeostasis, development, angiogenesis, and tumor progression. Accumulating evidence indicates that chemoattractant GPCRs and their ligands promote the progression of malignant tumors based on their capacity to orchestrate the infiltration of the tumor microenvironment by immune cells, endothelial cells, fibroblasts, and mesenchymal cells. This facilitates the interaction of tumor cells with host cells, tumor cells with tumor cells, and host cells with host cells to provide a basis for the expansion of established tumors and development of distant metastasis. In addition, many malignant tumors of the nonhematopoietic origin express multiple chemoattractant GPCRs that increase the invasiveness and metastasis of tumor cells. Therefore, GPCRs and their ligands constitute targets for the development of novel antitumor therapeutics. [ABSTRACT FROM AUTHOR]

An aerosol time-of-flight mass spectrometer (ATOFMS) was used to detect trimethylamine (TMA) in 0.52-1.9 μm particles at urban and rural sites in Southern Ontario during the summer and winter of 2007. During the summer, TMA-containing particles were observed exclusively during high relative humidity or fog events at both the urban and rural sites. In the wintertime, greater concentrations of TMA-containing particles were linked to cloud processing of aerosol in air masses originating from over agricultural and livestock areas. A laboratory study revealed that, at high relative humidity (∼100%), gas phase TMA at concentrations ranging from 2 to 20000 ppt partitions preferentially to acidic particles present in the ambient air. On the basis of the field and laboratory studies, it appears that gas phase TMA present in ambient air partitions onto pre-existing particles preferentially during periods of acidic cloud/fog processing, leading to the presence of TMA-containing particles in the 0.52-1.9 μm size range. [ABSTRACT FROM AUTHOR]

Twenty-six microsatellites were isolated and characterized from an AAG-enriched genomic library of Vallisneria spinulosa, a dominant submerged macrophyte in the middle-lower reaches of the Yangtze River. Microsatellite polymorphism was evaluated in a random population and 11 microsatellite loci were found polymorphic with 2–18 alleles per locus and observed heterozygosity ranging from 0.281 to 1.000. These polymorphic markers were expected to be valuable for population genetic and demographic analyses of V. spinulosa. [ABSTRACT FROM AUTHOR]