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B cells activated by antigen in T cell–dependent immune responses can become short-lived plasma cells, which remain in the spleen, or germinal center–derived memory or plasma cells, which show evidence of affinity maturation and, in the case of plasma cells, migrate to the bone marrow. We show that this cell fate decision can be governed by the cytokine environment engendered by activated dendritic cells (DCs). DCs from mice lacking the Fc receptor γ chain exhibited an activated phenotype in vitro. They secreted more of the proinflammatory cytokine IL-12, which led to the preferential generation of short-lived splenic plasma cells, with ensuing low affinity antibodies and a diminished recall response. Understanding the factors that regulate antigen-activated B cell differentiation and memory cell formation has implications for both antibody-mediated autoimmune disease and protective antibody responses.

Large quantities of β-SiC/SiOx coaxial nanocables have been synthesized with the presence of nickel catalyst by chemical vapor reaction using a mixture of milled Si and SiO2 powders and CH4 as the raw materials in a graphite reaction cell at relatively low temperature. Their microstructures were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersed X-ray (EDX) and X-ray diffraction (XRD). The synthesized β-SiC/SiOx coaxial nanocables possess a β-SiC crystal core with a uniform diameter of 10–60 nm and an amorphous silicon oxide wrapping layer with tens of nanometers in thickness, and their lengths are up to several tens of micrometers. The vapor–liquid–solid (VLS) mechanism was proposed to elucidate the growth process of β-SiC/SiOx coaxial nanocables.

Ecological shelter zones reconstruction is an ecosystem restoration and conservation project aimed to the ecological safety of nations, regions and basins. Reconstruction of ecological shelter zones of the upper reaches of the Yangtze River became one of the most important tasks of Western Development strategy. This article, taking Zhaotong as an example, studies the functional regionalization of ecological shelter zones. The study supplies a case for functional regionalization of small and medium regions whose main tasks are environment reservation. With the guidance of theories of functional regionalization, and based on the analysis of Zhaotong’s natural, ecological and socioeconomic factors, the paper suggests five principles for factors selection. These principles include: (1) reversing order evaluation; (2) selecting main factors; (3) keeping the integrality of administrative regions of towns; and (4) making the products acceptable by local government. To analyze spatial status of selected factors, LUCC data in 2002, 1:50,000 relief maps and town-unit socioeconomic statistical data in 2004 are used. RS and GIS tools are also applied to melt traditional and modern geographical methods. This would be useful to functional regionalization research in mountainous areas. As a conclusion, the leading functional regions of ecological conservation or economic development are suggested, respectively. Zhaotong city is divided into two-level functional regions. The first-level includes three leading functional regions and they will lead developing direction of sub-regions. The second-level includes eight sub-regions, which are policy implemented regions, and will supply guidance to Zhaotong’s ecological shelter zones reconstruction.

Many late intrusive granites with strongly peraluminous composition and fine-grained texture occur as stocks or apophysis in the Dadongshan main intrusive granite located in NW Guangdong Province. This paper reports the results of a petrogenetic study of some characteristic minerals (zircon, muscovite and andalusite) from the Zhutishi granite, one of the late intrusive granites in the Dadongshan granite. It is observed that the typological pattern of zircon population in the Zhutishi granite differs significantly from that in the Dadongshan granite, and that muscovite and andalusite, only found in the Zhutishi granite, are of magmatic origin. Therefore, this paper considers that the Zhutishi granite was unlike to be produced through crystal fractionation from the Dadongshan granitic magma as reported by previous authors, but is related closely to the formation of the Dadongshan granite. The hydrothermal fluid, produced by differentiation of the Dadongshan granitic magma at deep magmatic chamber, would penetrate into the source rock of the Zhutishi granite, and make it enriched in H 2 O and Al 2 O 3 ; and the decompression after the ascent of the Dadongshan granitic magma in extension regime promotes partial melting of the source rock of the Zhutishi granite, and produces the strongly peraluminous granitic magma. The model proposed in this paper seems to be more reasonable to explain the spacio-temporal relationship between the late intrusive granites with strongly peraluminous feature and the main intrusive granite with metaluminous feature

It is clear that the development of an autoimmune disease usually depends on both a genetic predisposition and an environmental trigger. In this study, we demonstrate that BALB/c mice develop a lupus-like serology following immunization with a peptide mimetope of DNA, while DBA/2 mice do not. We further demonstrate that the critical difference resides within the B cell compartment and that the naive B cell repertoire of DBA/2 mice has fewer B cells specific for the DNA mimetope. Differences in the strength of B cell receptor signaling exist between these two strains and may be responsible for the difference in disease susceptibility. BALB/c mice possess more autoreactive cells in the native repertoire; they display a weaker response to Ag and exhibit less Ag-induced apoptosis of B cells. DBA/2 mice, in contrast, display a stronger B cell receptor signal and more stringent central tolerance. This correlates with resistance to lupus induction. Thus, the degree to which autoreactive B cells have been eliminated from the naive B cell repertoire is genetically regulated and may determine whether a nonspontaneously autoimmune host will develop autoimmunity following exposure to Ag.

The difficulty in characterizing antigen-specific B cells that arise in the native B cell repertoire has been a formidable obstacle to understanding both protective and pathogenic antibody responses. We have developed a tetramer-based technique for identifying antigen-specific B cells. Biotin-labeled antigen is made tetrameric by interaction with streptavidin. The enhanced avidity of this antigenic compound for the B cell membrane permits the visualization, characterization and isolation of antigen-specific B cells.

Simulation is widely used to estimate losses due to default and other credit events in financial portfolios. The accurate measurement of credit risk can be modeled as a rare event simulation problem. While Monte Carlo simulation is time-consuming for rare events, importance sampling techniques can effectively reduce the simulation time, thus improving simulation efficiency. This chapter proposes a new importance sampling method to estimate rare event probability in simulation models. The optimal importance sampling distributions are derived in terms of expectation in the normal copula model developed in finance. In the normal copula model, dependency is introduced through a set of common factors of multiple obligors. The intriguing dependence between defaults of multiple obligors imposes hurdles in simulation. The simulated results demonstrate the effectiveness of the proposed approach to solving the portfolio credit risk problem.

Transgenic mice expressing anti-DNA antibodies have been extensively studied as a model for understanding B cell regulation in systemic lupus erythematosus (SLE). BALB/c mice transgenic for the R4A-gamma2b heavy chain of an anti-double-stranded DNA (dsDNA) antibody produce two populations of high-affinity anti-dsDNA B cells, one deleted, and the other anergized. We generated double-transgenic BALB / c mice expressing both the R4A-gamma2b heavy chain and the anti-apoptotic bcl-2 gene in the B cell compartment to study whether bcl-2 overexpression differentially affected anergic and deleted B cells. The double-transgenic mice (R4A/bcl-2) express elevated serum titers of both high- and low-affinity anti-dsDNA antibodies and display rescue of autoreactive B cells that are normally either deleted or anergized. Despite the presence of anti-dsDNA antibodies in their serum, R4A/bcl-2-transgenic mice do not develop nephritis, demonstrating that overexpression of bcl-2 is not by itself sufficient to allow disease progression. This phenotype resembles that of some SLE patients who have high titers of anti-DNA antibodies without nephritis.

A new organogelator, benzyl (4-methyl-1-oxo-1-(2-hexadecanoylhydrazinyl)pentan-2-yl)carbamate (designated as Cbz-Leu-HdHz), was designed and synthesized, which could self-assemble in many organic solvents and form the thermally reversible physical supramolecular organogels. The gel-sol phase transition temperatures (TGS) were determined as a function of gelator concentration and the corresponding enthalpies (ΔHg) were extracted. SEM, FT-IR and XRD were used for the investigations of the morphology and formation mechanism of organogels in the presence of the Cbz-Leu-HdHz. Based on the XRD data and molecular modeling, it was possible to propose packing modes for the formation of organogelator aggregates.

Genetic, epigenetic, and environmental factors influence the development of alcohol dependence (AD). Recent studies have shown that DNA methylation markers in peripheral blood may serve as risk markers for AD. Yet a genome-wide epigenomic approach investigating the role of DNA methylation in AD has yet to be performed. We conducted a population-based, case-control study of genome-wide DNA methylation to determine if alterations in gene-specific methylation were associated with AD in a Chinese population. Using the Illumina Infinium Human Methylation27 BeadChip, we assessed gene-specific methylation in over 27 000 CpG sites from DNA isolated from lymphocytes in 63 male AD in-patients and 65 male healthy controls. Using a multi-factorial statistical model, we observed differential methylation between cases and controls at multiple CpG sites with the majority of the methylated CpG sites being hypomethylated. Analyses with the online gene set analysis toolkit WebGestalt revealed that the genes of interest were enriched in multiple biological processes involved in AD development. Gene Ontology function annotation showed that stress, immune response and signal transduction were highly associated with AD. Further analysis by the Kyoto Encyclopedia of Genes and Genomes revealed associations with multiple pathways involved in metabolism through cytochrome P450, cytokine-cytokine receptor interaction and calcium signaling. Associations with canonical pathways previously shown to be involved in AD were also observed, such as dehydrogenases 1A (ADH1A), ADH7, aldehyde dehydrogenases 3B2 (ALDH3B2) and cytochrome P450 2A13. We present evidence that alterations in DNA methylation may be associated with AD, which is consistent with epigenetic theory.

By explore the role of serum soluble Fas (sFas) in occurrence and progression of delayed encephalopathy after acute carbon monoxide poisoning (DEACMP).Enzyme-linked immunosorbent assay (ELISA) was used to detect serum sFas levels in 40 patients with DEACMP in acute stage and convalescent stage, with 36 healthy elderly subjects as the control group.Serum sFas levels of the patients with DEACMP in both the acute and convalescent stages showed no significant difference from those in the control group (P=0.737 and 0.137, respectively), nor was any significant difference found between the patients in acute and exacerbation stages (P=0.059).Serum sFas is not involved in the occurrence and progression of DEACMP.

Objective To examine the prevalence and correlates of diabetes in a large sample of Chinese patients with schizophrenia on long-term clozapine treatment, because this population previously has received little systematic study. Methods Two hundred and six inpatients meeting Diagnostic and Statistical Manual of Mental Disorders, 4th Edition schizophrenia criteria were recruited in a cross-sectional naturalistic study, and compared with 615 healthy control subjects matched for age, sex, education, and body mass index (BMI). The patient's psychopathology was assessed using the Positive and Negative Syndrome Scale (PANSS). Diagnoses of diabetes were established through review of medical records and fasting blood glucose testing, or an oral glucose tolerance test. Results Diabetes mellitus was more common in patients than in the normal controls (22.3% vs 6.2%) (odds ratio = 4.37, confidence interval (CI) 2.76–6.92, p

Tire forming line converts from single production to combination production gradually, from the traditional serial intermittent working pattern to paralleling continuous working pattern. Combine the relevant equipment needed in the process of the tire forming line, and then the molded parts will pass the working places in accordance with certain crafting routes and rhythm sequentially, which will realize the aim of consecutive and repeated production. The designing method should start with the composition and forming pattern. The main pattern can take the form of mobile locating and carry out the forming operation alternately. The programming should reflect the flexibility and use the idea of structured programming, which can make the structure of the programming showed clearly. The generalization and standardization of some programs can make them easy to modify and simplify their regulations. Intelligent robots can replace human beings' operations in some processes. The new methods can improve production efficiency, lower process loss, and decrease production cost.

This paper considers the problem of Vehicle Routing Problem with stochastic demands and simultaneous delivery and pickup. An effective algorithm based on cross-entropy is designed to solve the model. The cross-entropy method is a new generic approach to combinatorial and multi-extremal optimization and rare event simulation. Numerical experiments have been conducted and the results indicate that the method can effectively solve this problem.

To examine the prevalence and correlates of diabetes in a large sample of Chinese patients with schizophrenia on long-term clozapine treatment, because this population previously has received little systematic study.Two hundred and six inpatients meeting Diagnostic and Statistical Manual of Mental Disorders, 4th Edition schizophrenia criteria were recruited in a cross-sectional naturalistic study, and compared with 615 healthy control subjects matched for age, sex, education, and body mass index (BMI). The patient's psychopathology was assessed using the Positive and Negative Syndrome Scale (PANSS). Diagnoses of diabetes were established through review of medical records and fasting blood glucose testing, or an oral glucose tolerance test.Diabetes mellitus was more common in patients than in the normal controls (22.3% vs 6.2%) (odds ratio = 4.37, confidence interval (CI) 2.76-6.92, p0.001). The prevalence of diabetes increased with age across five age-groups as compared with normal controls (X(2) = 18.0, df = 4, p = 0.001). The PANSS total score and sub-scores showed no differences between the diabetic and non-diabetic groups. Logistic regression in the patients revealed significant associations between diabetes and a family history of diabetes (p0.001), age (p0.01), and BMI (p0.05).Long-term clozapine treatment was associated with an increased and clinically important risk of diabetes mellitus in Chinese chronic schizophrenic patients, which is consistent with previous reports in Western populations.

The present situation of paperless examination system is introduced, this paper aims at the character of poor commonality for most of paperless examination system, a paperless examination system based on WEB has been designed, the management mode and examination mode of this system will be separated by the network frame of B/S. The design of database system uses the universal management mode of the database of curriculum and the database of examination information to realize its commonality. The adaptive learning technology of difficulty coefficient of examination questions is presented in order to making the system have high efficiency of assembling test paper in this paper. What's more, different display orders of examination questions for those neighboring students through a new algorithm already are realized, this measure can prevent examination cheats effectively, and fairness of each examination can be guaranteed. At the same time, this system have also resolved these problems such as that replacing machine and the second login because of other reasons and so on, these will ensure the security of examination. The technologies of automatic paper rating technology and automatic outputting report of examination results to Excel sheet etc. are used in order to realize functional requirements of the examination system such as automation, security and high efficiency of this system.

To establish models of different susceptibility of heroin-induced conditioned place preference (CPP) in rats and investigate the relation between novel environmental response and heroin-dependent susceptibility.After an open-field test, 70 male Sprague-Dawley rats were classified into 2 groups according to the numerical value of heroin-induced CPP, each accounting for 30%. The correlation between open-field test and CPP was analyzed.CPP value was much higher than pre-test scores in the rats after exposure to heroin (P0.01). Compared with the low-CPP group, the high-CPP group had much higher scores in open-field test (P0.01). The deviation of resident time at natural preference side tested and pre-tested had positive correlation with open-field test (P0.05).Heroin-induced CPP model of different susceptibilities could be successfully established by chronic heroin exposure. The novel environmental response is a reliable predictor for its vulnerability to develop heroin dependence.

Receptor editing or secondary Ig gene rearrangement occurs in immature, autoreactive B cells to maintain self-tolerance. Here we show that nonspontaneously autoimmune mice immunized with a peptide mimetope of DNA develop peptide- and DNA-reactive antibodies. Antigen-specific B cells display a follicular B cell phenotype. As these cells move into the memory compartment, many express RAG protein and acquire expression of both κ and λ light chains. Thus, this study provides evidence for receptor editing occurring in a mature, antigen-activated B cell population. Because the receptor editing observed here occurred in an autoreactive response to antigen, it may function to maintain peripheral tolerance.

Northwest China includes six provincial districts of Inner Mongolia Autonomous Region, Shaanxi Province, Gansu Province, Qinghai Province, Ningxia Autonomous Region and Xinjiang Autonomous Region. This region is located in the alpine frigid region, and region and the loess plateau, therefore, its eco-environment is frail and economy is under-developed. Based on climate data, land use data, and socio-economic statistic data, this article analyzed the data of precipitation, air temperature, humidity, population, GDP, industrial structure, land use changes, designed water-heat condition, and integrated human activity pressure. By utilizing ArcGIS 8, we divided the eco-economic region into three-level categories according to the environment condition and human activities in county scale in Northwest China, and analyzed the basic characteristics and main eco-economic problems of each eco-economic region.

The style of water use was restricted in a large extent by the fragile eco-environment in Ningxia and Inner Mongolia Autonomous along the Yellow River. Applying the runoff data and the field survey data, we analyze the main contradictions between water use and environment in this area. And by overlaying the meteorological data with the statistic data of soci-economy, we regionalize the ecologically geographical zones. We also analyzed the main style of water use based on the ecologically geographical zones. In conclusion, it is strongly proposed that harmonious relationships in water-man and water-environment systems have to be established to realize sustainable water supply in this area.

Primary works of data collection and analysis were presented to examine farming productivity in the Yellow River basin, a semiarid region in Northwest China. Descriptive statistics, correlation analysis and a proposed productivity model based on land use types were used to characterize the data and to evaluate the impact of resources and technologies, especially water resources. A database in grid system was established for a coupled hydroeconomic model for examining the relationships between the farming productivity and water sustainability. Results showed that the farming productivity had increased by one and one half to three folds in the past two decades, which was heavily dependent on irrigation. Fertilizer had high correlation with farming productivity and could fairly well explain the variations of farming productivity in most districts. Meanwhile, water resources were seriously depleted basin-wide due to the overuse. Therefore, effective management of water resource in agricultural production is critical for water sustainability in the region.

Immunization against phosphorylcholine (PC) linked to a protein protects mice against Streptococcus pneumoniae when used parenterally, and against Salmonella typhimurium when used orally after entrapment in D,L-Lactide-co-Glycolide microspheres. Here, we immunized BALB/c mice intranasally with a serotype 3 S. pneumoniae strain. Immunization was followed by a rise in anti-PC IgA and IgG titers in serum and in pulmonary secretions, but not by any rise in anti ds-DNA antibody nor any glomerular Ig deposition. The survival rates were 91 and 76% in the two groups of mice, respectively. These rates were significantly higher than those in control mice immunized intranasally either with Thyr loaded in microspheres (0%), blank microspheres (22%), free Thyr (17%), and saline (18%). This demonstrates that the mucosal route is effective for vaccination against S. pneumoniae pneumonia with PC linked to a protein carrier. It constitutes another important step forward in the development of the concept that PC can be used as a mucosal immunogen for protection against the different diseases caused by PC-bearing bacteria.

This randomized, double-blind study compared the efficacy and safety of blonanserin and risperidone to treat Chinese schizophrenia patients aged ≥18 and