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Deep learning (DL) based knowledge tracing (KT) models have challenges for uninterpretable prediction and parameter representation in educational applications, though they achieved remarkable outcomes in predicting the exercise performance of students. This paper proposes a novel knowledge tracing model of high precision and interpretability (named XKT) for questions with multiple knowledge concepts based on cognitive learning theories and multidimensional item response theory (MIRT). The XKT consists of three differentiable network components: multi-feature embedding, cognition processing network, and MIRT-based neural predictor, which aim to provide an explainable prediction of student exercise performance. Specifically, in XKT, multi-feature embedding learns the rich semantic representation (e.g., knowledge distribution information) to enhance knowledge tracing using a cognition processing network. The cognition processing network performs selective perception, ability memory processing, and long-term knowledge memory processing to ensure the explainable factor representation for the MIRT-based neural predictor. Lastly, the MIRT-based neural predictor employs psychometric parameters to interpret student exercise predictions better. Extensive experiments on four real-world datasets show that XKT outperforms existing KT methods in predicting future learner responses. Moreover, ablation studies further show that XKT offers good interpretability of student performance predictions with multiple knowledge concepts, indicating excellent potential in real-world educational applications.

Three-dimensional point cloud classification is fundamental but still challenging in 3-D vision. Existing graph-based deep learning methods fail to learn both low-level extrinsic and high-level intrinsic features together. These two levels of features are critical to improving classification accuracy. To this end, we propose a dual-graph attention convolution network (DGACN). The idea of DGACN is to use two types of graph attention convolution operations with a feedback graph feature fusion mechanism. Specifically, we exploit graph geometric attention convolution to capture low-level extrinsic features in 3-D space. Furthermore, we apply graph embedding attention convolution to learn multiscale low-level extrinsic and high-level intrinsic fused graph features together. Moreover, the points belonging to different parts in real-world 3-D point cloud objects are distinguished, which results in more robust performance for 3-D point cloud classification tasks than other competitive methods, in practice. Our extensive experimental results show that the proposed network achieves state-of-the-art performance on both the synthetic ModelNet40 and real-world ScanObjectNN datasets.

Multilabel classification (MLC) refers to associating each instance with multiple labels simultaneously. MLC has gained much importance due to its ability to better reflect the complexity of the real world classification problems. Fuzzy system (FS) has excellent nonlinear modeling capability and strong interpretability, which makes it a promising model for complex MLC problems. However, it is widely known that FS suffers from the “curse of dimensionality.” Here, an adaptive membership function (MF) along with its generalized version is proposed to address high-dimensional problems. These MFs can effectively overcome “numeric underflow” in FS while preserving interpretability as much as possible. On this basis, a novel fuzzy rule based MLC framework called multilabel high-dimensional Takagi–Sugeno–Kang fuzzy system (ML-HDTSK FS) is proposed. This model can handle data with over ten thousand dimensionality. In addition, ML-HDTSK FS uses a decomposed label correlation learning strategy to efficiently capture both high and low levels of relationship between labels, and adopts a group $L_{21}$ penalty to realize the learning of label-specific features. Combining these two new multilabel learning strategies and the novel adaptive MF, ML-HDTSK FS becomes a more powerful tool for various MLC problems. The effectiveness of ML-HDTSK FS is demonstrated on seventeen benchmark multilabel datasets, and its performance is compared with eleven MLC algorithms. The experimental results confirm the validity of the proposed ML-HDTSK FS, and demonstrate the superiority of it in dealing with MLC problems, especially for high dimensional ones.

Graphical Abstract

A major limitation of fuzzy or neuro-fuzzy systems is their failure to deal with high-dimensional datasets. This happens primarily due to the use of T-norm, particularly, product or minimum (or a softer version of it). Thus, there are hardly any work dealing with datasets having features more than hundred or so. Here, we propose a neuro-fuzzy framework that can handle datasets with even more than 7000 features! In this context, we propose an adaptive softmin (Ada-softmin) which effectively overcomes the drawbacks of “numeric underflow” and “fake minimum” that arise for existing fuzzy systems while dealing with high-dimensional problems. We call it an adaptive Takagi–Sugeno–Kang (AdaTSK) fuzzy system. We then equip the AdaTSK system to perform feature selection and rule extraction in an integrated manner. In this context, a novel gate function is introduced and embedded only in the consequent parts, which can determine the useful features and rules, in two successive phases of learning. Unlike conventional fuzzy rule bases, we design an enhanced fuzzy rule base, which maintains adequate rules but does not grow the number of rules exponentially with features that typically happens for fuzzy neural networks. The integrated feature selection and rule extraction AdaTSK (FSRE-AdaTSK) system consists of three sequential phases: 1) feature selection; 2) rule extraction; and 3) fine tuning. The effectiveness of the FSRE-AdaTSK is demonstrated on 19 datasets of which five are in more than 2000 dimension including two with more than 7000 features. This may be the first attempt to develop fuzzy rule-based classifiers that can directly deal with more than 7000 features without requiring separate selection of features or any other dimensionality reduction method.

Nevertheless, simply restricting access to work may not stop employees from experiencing distress if workloads are high and/or if workplaces still expect fast responses as proof that employees are working. Therefore, if an organization's norms value long work hours and availability at all times, disconnection policy should be incorporated into a much broader program of organizational change toward sustainable work.4 While the policy is intended to change organizations' work culture, it may not be able to do so without substantial cultural and mindset shifts. At the national level, governments have proposed legislation on the right to disconnect, which allows workers to avoid responding to work-related communications after work hours. When workers perceive that their organization values work-life integration - such as bringing work home - they are less able to detach from work even when they would prefer to. [Extracted from the article]

We reported earlier that β-cell-specific overexpression of glutathione peroxidase (GPx)-1 significantly ameliorated hyperglycemia in diabetic db/db mice and prevented glucotoxicity-induced deterioration of β-cell mass and function. We have now ascertained whether early treatment of Zucker diabetic fatty (ZDF) rats with ebselen, an oral GPx mimetic, will prevent β-cell deterioration. No other antihyperglycemic treatment was given. Ebselen ameliorated fasting hyperglycemia, sustained nonfasting insulin levels, lowered nonfasting glucose levels, and lowered [HbA.sub.1c] levels with no effects on body weight. Ebselen doubled β-cell mass, prevented apoptosis, prevented expression of oxidative stress markers, and enhanced intranuclear localization of pancreatic and duodenal homeobox (Pdx)-1 and v-maf musculoaponeurotic fibrosarcoma oncogene family, protein A (MafA), two critical insulin transcription factors. Minimal β-cell replication was observed in both groups. These findings indicate that prevention of oxidative stress is the mechanism whereby ebselen prevents apoptosis and preserves intranuclear Pdx-1 and MafA, which, in turn, is a likely explanation for the beneficial effects of ebselen on β-cell mass and function. Since ebselen is an oral antioxidant currently used in clinical trials, it is a novel therapeutic candidate to ameliorate fasting hyperglycemia and further deterioration of β-cell mass and function in humans undergoing the onset of type 2 diabetes., Exposure of β-cells to supraphysiologic glucose levels causes loss of insulin gene transcription factors, insulin mRNA, and glucose-induced insulin secretion (1-3). These adverse changes can be partially ameliorated by antioxidants [...]

The various factors that lead to managerEs occupational stress in private, as well as state-owned enterprises in the PeopleEs Republic of China are discussed. The private enterprisesE managers are shown to exhibit higher levels of occupational stress, as compared to the managers in the state-owned enterprises.

In this paper, we first define a measure of statistical sensitivity of a zero-order Takagi–Sugeno (TS) fuzzy neural network (FNN) with respect to perturbation of weights and parameters of the system. Then we derive measures of sensitivity of the system with respect to additive and multiplicative noises to the consequent parameters. For this we consider a multiple-input multiple-output (MIMO) FNN. The derivation can be easily extended to sensitivity with respect to other parameters as well. These measures of sensitivity are then used as regularizers to the loss function while training the system. Finally, to validate the sensitivity-based learning method, another definition of statistical sensitivity measure, based on absolute output error, is proposed, and its corresponding expression for additive/multiplicative perturbations of the consequent parameters is derived as well. Using simulation results on one classification problem and two regression problems, the effectiveness of the sensitivity measures is demonstrated. [ABSTRACT FROM AUTHOR]

Background: We systematically characterized an allergic dimer impurity in cefmenoxime hydrochloride raw material by UV, IR, HR-MS, 1D, and 2D NMR for the first time. Methods: The dimer stock solution of cefmenoxime hydrochloride was obtained by the degradation method. The target dimer impurity in the stock solution was separated by preparative RP-HPLC and purified by the freeze-drying method. By comparing the dimer to cefmenoxime hydrochloride, the functional groups corresponding to the characteristic peaks of UV and IR spectra were identified, and the molecular formula and mass fragmentation pattern were determined using HR-MS. Results: Then, based on the full assignment of 1 H and 13 C NMR signals， the dimerized position was confirmed and its absolute configuration was identified by 1D and 2D NMR. Conclusion: This study provided a structural basis for the allergic study of dimer impurities in cephalosporin drugs.

Objective: To systematically characterize the impurity profile in Daptomycin raw material by 2 Dimensional LC/MSn. Methods: The target impurity was separated by first Dimensional HPLC and enriched by a 500μl loop, then desalted using the on-line second Dimensional HPLC and analyzed by MS detector in positive mode. Their structures were characterized based on the degradation mechanism and mass fragmentation regularity of the cyclic lipopeptide, as well as the molecular thermodynamic calculation. Results: A total of 12 impurities were characterized in the raw material, including 6 degradation products; 8 impurities are reported for the first time. The mass fragmentation regularities of 2 β-isomers of Asp residue were summarized. Conclusion: The structures of impurities in Daptomycin raw material, especially for β-isomer impurities, could be rapidly identified by on-line 2 Dimensional LC/MSn method together with the molecular thermodynamic calculation.

The versatility and flexibility of organic photoelectric materials endow organic photovoltaic cells fine function modulation and huge commercial potential. In this work, a new noncovalent fused-ring small molecule acceptor (SMA) BID-4F has been synthesized for high-efficient organic solar cells (OSCs). BID-4F consists of a diflurobenzothiadiazole (DFBT) core, ladder-like indacenodithiophene (IDT) spacers, and dicyanoindanone electron-withdrawing end groups, which are supposed to be conformationally interlocked by noncovalent interactions, leading to good molecular planarity. In addition, compact solid state stacking was revealed by UV–vis–NIR absorption spectrum. The optimized PM6:BID-4F based device delivers an eminent power conversion efficiency (PCE) of 12.30% with a high open-circuit voltage (Voc) of 0.92 V and a high fill factor (FF) of 74.3%. Most importantly, the PCE and FF are among one of the highest values reported for the OSCs based on the unfused-ring SMAs. Overall, our work demonstrates that the unfused ring central framework with high molecular planarity through noncovalent interactions provides a good strategy to construct highly efficient SMAs.

Objective Probiotics may be efficacious in preventing ventilator-associated pneumonia (VAP). The aim of this network meta-analysis (NMA) was to clarify the efficacy of different types of probiotics for preventing VAP.Methods This systematic review and NMA was conducted according to the updated preferred reporting items for systematic review and meta-analysis. A systematic literature search of public databases from inception to 17 June 2018 was performed.Results NMA showed that “Bifidobacterium longum+ Lactobacillus bulgaricus+ Streptococcus thermophiles” was more efficacious than “Ergyphilus” in preventing VAP (odds ratio: 0.15, 95% confidence interval: 0.03–0.94). According to pairwise meta-analysis, “B. longum+ L. bulgaricus+ S. thermophiles” and “Lactobacillus rhamnosus” were superior to placebo in preventing VAP. Treatment rank based on surface under the cumulative ranking curves revealed that the most efficacious treatment for preventing VAP was “B. longum+ L. bulgaricus+ S. thermophiles” (66%). In terms of reducing hospital mortality and ICU mortality, the most efficacious treatment was Synbiotic 2000FORTE (34% and 46%, respectively).Conclusions Based on efficacy ranking, “B. longum+ L. bulgaricus+ S. thermophiles” should be the first choice for prevention of VAP, while Synbiotic 2000FORTE has the potential to reduce in-hospital mortality and ICU mortality.

Legacy organic contaminants, such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), and several currently used organic contaminants, such as novel brominated retardants (NBFRs), organophosphate flame retardants (OPFRs), and Dechlorane Plus (DPs), were measured in the segmented hair and hand wipes of e-waste dismantling workers and in the dust from their workplace in an e-waste recycling site in South China to assess the accumulation and sources of organic contaminants in the hair shaft. The median concentrations of DPs, PBDEs, NBFRs, PCBs and OPFRs in hair samples were 23.5, 154, 156, 349, and 371 ng/g, respectively. A linear increase in organic contaminant concentrations was found along the hair shaft, with significant differences among each segment, while the age-related patterns were similar among the 7 hair segments. A linear relationship was found between the accumulation rates and the log KOW,indicating that the accumulation rates of organic contaminants along the hair shaft decreased with increasing log KOWvalues. Enantiomer fraction (EF) values of PCB-132 in distal segments were close to those in dust and air, while EFs in proximal segments were close to those in serum. The contributions of PCBs from external sources to hair increased with the distance from the scalp of hair segments, from 67.8% in 0–3 cm segments to 95.9% in 18–21 cm segments.

ABSTRACTBacillus Calmette-Guerin (BCG) is a potent agent for the prevention of tuberculosis. Current studies have regarded BCG as an immunomodulator. However, there is little information on whether it can be used to inhibit airway inflammation and airway remodeling caused by asthma. Therefore, in this study, we investigate the role of epithelial–mesenchymal transition (EMT) in airway inflammation and airway remodeling as well as the possible therapeutic mechanism of BCG for the treatment of asthma. Wistar rats were sensitized and challenged by ovalbumin for 2 weeks or 8 weeks. BCG was subcutaneously administered daily before every ovalbumin challenge to determine its therapeutic effects. The 2 weeks model group showed extensive eosinophilia, chronic inflammatory responses, bronchial wall thickening, airway epithelium damage, increased levels of transforming growth factor β 1 (TGF-β1) in both bronchoalveolar lavage fluid and sera, decreased expression of epithelial marker E-cadherin, and increased expressions of mesenchymal markers α-smooth muscle actin (α-SMA) and Fibronectin (Fn). Except for inflammatory responses, all responses were more significant in the 8 weeks model group which displayed characteristics of airway remodeling including subepithelial fibrosis, smooth muscle hypertrophy, and goblet cell hyperplasia. When compared with the model groups, BCG administration inhibited airway inflammation and airway remodeling, decreased TGF-β1levels, upregulated expression of E-cadherin, and downregulated expression of α-SMA and Fn. The present study suggests for the first time that increased secretion of TGF- β1induced by asthmatic chronic inflammation may result in EMT, which is one of the most important mechanisms of airway inflammation and airway remodeling seen with asthma. BCG alleviates airway inflammation and airway remodeling by preventing TGF-β1induced EMT, therefore BCG may be a new therapy for treating asthma.

Straw return is a promising strategy for managing soil organic carbon (SOC) and improving yield stability. However, the optimal straw return strategy for sustainable crop production in the wheat (Triticum aestivumL.)-cotton (Gossypium hirsutumL.) cropping system remains uncertain. The objective of this study was to quantify the long-term (10 years) impact of C input on SOC sequestration, soil aggregation and crop yields in a wheat–cotton cropping system in the Yangtze River Valley. Five treatments were arranged with a single-factor randomized design as follows: no straw return (Control), return of wheat straw only (Wt), return of cotton straw only (Ct), return of 50% wheat and 50% cotton straw (Wh-Ch) and return of 100% wheat and 100% cotton straw (Wt-Ct). In comparison to the Control, the SOC content increased by 8.4 to 20.2% under straw return. A significant linear positive correlation between SOC sequestration and C input (1.42-7.19 Mg ha−1yr−1) (P<0.05) was detected. The percentages of aggregates of sizes >2 and 1–2 mm at the 0–20 cm soil depth were also significantly elevated under straw return, with the greatest increase of the aggregate stability in the Wt-Ct treatment (28.1%). The average wheat yields increased by 12.4–36.0% and cotton yields increased by 29.4–73.7%, and significantly linear positive correlations were also detected between C input and the yields of wheat and cotton. The average sustainable yield index (SYI) reached a maximum value of 0.69 when the C input was 7.08 Mg ha−1yr−1, which was close to the maximum value (SYI of 0.69, C input of 7.19 Mg ha−1yr-1) in the Wt-Ct treatment. Overall, the return of both wheat and cotton straw was the best strategy for improving SOC sequestration, soil aggregation, yields and their sustainability in the wheat-cotton rotation system.

Weihe River Watershed above Linjiacun Section is taken as the research objective in this paper and NH3-N is chosen as the water quality parameter. According to the discharge characteristics of point source pollutions and non-point source pollutions, a new method to estimate pollution loads-characteristic section load method is suggested and point source pollution and non-point source pollution loads of Weihe River Watershed above Linjiacun Section are calculated in the rainy, normal and dry season in the year 2007. The results show that the monthly point source pollution loads of Weihe River Watershed above Linjiacun Section are discharged stably, the monthly non-point source pollution loads of Weihe River Watershed above Linjiacun Section change greatly, the non-point source pollution load proportions of total pollution load of NH3-N are gradually decreased in the rainy, normal and wet periods.

Superscalar pipelining is to improve instruction-level parallelism and advanced technology, and is widely used in the computer's central processor and graphic accelerator. In this paper, we made use of advantage of CPLD devicesinherent flexibility, usability, predictability and so on, to achieve superscalar pipelining, designed and constructed a processor model superscalar pipeline machine based on RISC instruction set. Using EDA technology with top-down design methods, and gave the processor model hardware verification and performance test results, and had explored the use of EDA technology processor design ideas and methods.

Cashew classification technology is tested by the method of orthogonal test in this paper, and it found the main factors, the trend and the optimum operating parameters of cashew classification by observing three factors of the sieve length, drum speed and the number of turns which influenced mixed-level rate and classification efficiency. We did regression analysis of test data by using SPSS software, and got the universal formula of cashews samples grading for cashews samples. The paper provided theoretical basis for the structural design and optimization of the operating parameters of the cashew grading machine.

The objective of this study was to establish and optimize high-performance thin-layer chromatography (HPTLC) analysis of gatifloxacin and related substances by the method of design of experiment (DOE). First, preliminary screening of 22 solvents was performed using uniform design (UD) to establish the developing solvent proposed to be optimized. The optimal proportions of components in the developing solvent were established by using central composite design (CCD) to establish and validate HPTLC analysis of gatifloxacin and related substances. Using DOE, it was found that the optimal proportions (by volume) of components in the developing solvent in the HPTLC analytical method were methanol-1,2-dichloroethane-concentrated ammonia solution-acetonitrile (2.8:7.2:0.5:0.5, v/v). Methodological validation showed that the established HPTLC method could separate gatifloxacin and 8 related substances with similar structures effectively. In particular, impurity pairs with the greatest separation difficulty (due to their similar polarities and dipole moments), e.g., impurity #3 (8-fluorogatifloxacin) and impurity #8 (gatifloxacin 2-methylpiperazine), impurity #3, and substance #9 (gatifloxacin), could also be separated effectively. The HPTLC method was simple, accurate, reliable, and suitable for rapid qualitative analysis of gatifloxacin and related substances in routine tests. Additionally, the analytical results presented here may provide useful supplemental information on the current reversed phase high-performance liquid chromatography (RP-HPLC) method, especially in terms of the mechanism of normal-phase separation.

Column switching LC/MS methods were developed for rapid identification of impurities in cefdinir. Based on the mechanism by which cephalosporins are degraded, stress tests were designed and performed. It was found that eight main impurities were degradation products and five impurities originated from the synthesis process. Cefdinir bulk material was eluted as gradient on a C18 column, with 0.25 tetramethyl ammonium hydroxide solution (pH5.5)-acetonitrilemethanol as mobile phase. According to the retention time of different impurities, the target impurities were separated and enriched in another chromatographic column using column switching technology. Then the target impurity was desalted using an elution of 0.5 formic acid solution. Mass analysis was performed by elution with a mobile phase consisting of 1.0 formic acid-acetonitrile (3:7). The structures of ten related impurities were characterized on the bases of MS/MS data, general mass fragmentation pathway of cefdinir, and UV spectra. This study provides the material basis for the related substances of cefdinir in the Chinese Pharmacopeia 2010 edition. It also provides an effective means for the rapid identification of impurities in chromatographic systems containing non-volatile salt.

This paper presents a fabricating process and microstructural features of TiB2+TiC duplex particulates reinforced surface composite with carbon steel matrix. The effect of ferrous-titanium addition on microstructures is investigated and analyzed. The results showed that the surface compound layer do not exhibit at lower addition, but appear at higher addition. With increasing ferrous-titanium addition, the concentration and size of the synthesized particles at the surface compound layer are decreased, but the tendency of uniform distribution increased.

Na+ doped sample Li0.95Na0.05FePO4 was prepared through solid state method. Structure characterization shows Na+ is successfully introduced into the LiFePO4 matrix. Scanning electron microscopy shows the particle size mainly ranges in 1-3 um. X-ray diffraction Rietveld refinement demonstrates lattice distortion with an increased cell volume. As one cathode material, it has a discharge capacity of 150 mAh/g at 0.1 C rate. The material exhibits a capacity of 109 and 107 mAh/g at 5 and 7.5 C respectively. When cycled at 1 and 5 C, the material retains 84% (after 1000 cycles) and 86% (after 350 cycles) of the initial discharge capacity respectively indicating excellent structure stability and cycling performance. Na+ doping enhances the electrochemical activity especially the cycle performance effectively.

The taxonomy of Nyssa(Nyssaceae) in China is confused and uncertain due to differing views about how many species should be recognized, and a scarcity of good morphological differential characters. In the present study, we examined 52 morphological characters from up to fifty accessions each of six of the seven species recognized in the Flora of China: N. yunnanensis, N. javanica, N. sinensis, N. shangszeensis, N. shweliensisand N. wenshanensis.Based on both principal coordinate analysis and UPGMA cluster analysis, N. yunnanensisand N. javanicawere both morphologically distinct. However, accessions of N. sinensis, N. shangszeensis, N. shweliensisand N. wenshanensiswere intermixed in both analyses and could not be discriminated from each other. Sequence data from nuclear ITS and the chloroplast regions trnH-psbA, rps16r-f, trnL-rps32F, trnS-Gand trnL-Fwere used to further analyze the Nyssaspecies listed above, together with N. aquaticaand N. sylvaticafrom North America. All analyses of the DNA data using maximum parsimony, maximum likelihood and Bayesian methods strongly supported the monophyly of Nyssa.Within Nyssa, N. yunnanensisand N. javanicawere resolved as sister species, which were genetically distinct. The other four Chinese taxa were barely differentiated by molecular data, with only N. shangszeensisand N. wenshanensisweakly supported as monophyletic. Hence, based on morphological and molecular data, we recommend that N. shangszeensis, N. shweliensisand N. wenshanensisbe reduced to synonyms of N. sinensis,and only N. sinensis, N. yunnanensisand N. javanicabe recognized for Flora of China.The American N. aquaticaand N. sylvaticawere sister species in the cpDNA but not in the ITS analyses, indicating possible reticulate evolution.

A novel approach to modify polymeric pigment dispersants with polysiloxanes was developed based on the sequential atom transfer radical polymerization (ATRP) of styrene (St) and tert-butyl acrylate (tBA), using multifunctional α-bromoisobutyryl-containing poly (dimethylsiloxane) (PDMS-Brm) as the macroinitiators and CuBr/N,N,N,N,N- pentamethyldiethylenetriamine (PMDETA) as the catalyst system. The PDMS-Brm macroinitiators were obtained from the sequential hydrosilylation of commercially available methyl polysiloxanes containing SiH groups with allyl alcohol and then α-bromoisobutyryl bromide. And then, a series of well-defined comb-like graft copolymers with a PDMS backbone and several polystyrene-block-poly (tert-butyl acrylate) (PS-b-PtBA) side-chains were synthesized via ATRP. After hydrolyzing the tert-butyl groups, the comb-like copolymers may serve as multifunctional dispersing agents in the pigment printing.

A quantitative analysis method based on near infrared (NIR) spectroscopy was developed for determining the azithromycin content and its degradation product impurity (decladinosylazithromycin) in azithromycin for injection. Two quantitative models were obtained by evaluating 18 laboratory samples and 44 commercial samples formulated as hydrochlorate, phosphate, lactate and citrate salts. The samples had an azithromcyin content ranging from 74.2% to 91.0% (w/w) and decladinosylazithromycin ranging from 0.1% to 7.7% (w/w). The root mean square error of cross-validation for the azithromycin model and decladinosylazithromycin model were 1.54% and 0.49%, respectively. The estimated limit of detection and limit of quantification for the decladinosylazithromycin calibration were about 1.2% and 4.1% (w/w), respectively. In addition, the quantitative models were validated in terms of specificity, linearity, accuracy, repeatability and intermediate precision, according to the International Conference on Harmonisation guidelines, by evaluating the characteristics of the NIR spectra. The results showed that the models were satisfactory. Our results demonstrated that a universal quantitative model based on NIR diffuse reflectance spectroscopy could be used as a quick and reliable method for quality control of low-dose impurities in pharmaceutical drugs.

800x600 Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";} Web Services Composition (WSC)-based applications are widely using in the heterogeneous environment, which has inevitably led to the need for reliable methods for the WSC paradigm. This paper presents a formal definition of Web services composition, and then analyzes task dependency rules of dataflow and behavior in Web services composition net system, finally, we introduce execution semantic of Web services composition net.

Web Services Composition (WSC)-based applications are widely using in the heterogeneous environment, which has inevitably led to the need for reliable methods for the WSC paradigm Firstly this paper presents formal description of Web service and then proposes a novel WSC compensation method based on paired net which can dynamically construct agile compensation business process according to original business process and implements it. Secondly, we introduce a formal definition of execution logs, which ensures the reliability and consistency of composition execution. Finally, Composition-based application of trip reservation process shows that it is feasible.

The semantic web brings a new opportunity for efficient information organization and search. To meet the special requirements of the educational field, this paper proposes an intelligent search engine enabled by educational semantic support service, where three kinds of searches are integrated into Educational Information Intelligent Search (EIIS) framework, and web-based resources and local e-resources are both identically semantically processed. During the design, the EIISReasoning and its relevant rule sets are constructed to automatically reason semantic concepts to diverse levels by a semantic factor and a response time factor. Furthermore, the EIISRanking algorithm applies two-level ranking by a factor of semantic similarity, and the same relevance is differentiated in terms of the educational field’s needs. The experiments show that the EIIS engine with semantic services has a better precision rate and improved ranking performance.

Abstract: Classical congenital adrenal hyperplasia (CAH) is characterized by the defects in cortisol and aldosterone secretion, and accompanied with adrenal hyperandrogenism. It is likely that the impaired adrenocortical function and intermittent treatment-related hypercortisolism may predispose patients to the development of metabolic syndrome in adulthood. Our aim was to assess the impact of hyperandrogenism on metabolic profiles in CAH women without glucocorticosteroid treatment. We evaluated the clinical characteristics and metabolic profiles in 30 untreated Chinese female adults with simple virilizing congenital adrenal hyperplasia (SV–CAH). Mutation analysis was performed by sequencing the entire 21-hydroxylase gene (CYP21A2). As compared with the controls, CAH patients had higher BMI (BMI, 21.5 ± 2.1 vs. 20.0 ± 1.8 kg/m2, P < 0.05), higher 2 h post-load plasma glucose levels (6. 35 ± 1.74 vs. 5. 35 ± 1.17 mmol/l, P < 0.05), higher serum triglycerides (TG) (1.12 ± 0.64 vs. 0.63 ± 0.15 mmol/l, P < 0.01), and lower high-density lipoprotein cholesterol (HDL-c) (1.30 ± 0.39 vs. 1.67 ± 0.29 mmol/l, P < 0.01). Moreover, CAH patients had higher fasting insulin and homeostasis model assessment of insulin resistance (HOMA-IR) (1.81 ± 0.99 vs. 1.24 ± 0.50, P < 0.05), while ΔIns30/ΔGlu30 showed no statistically significant difference in two groups. In addition, a marked reduction of serum adiponectin levels were observed in CAH patients (7.0 ± 3.3 vs. 13.2 ± 4.8 μg/ml, P < 0.001), however, serum CRP levels were not different between patients and the controls. Further regression analysis showed that higher serum testosterone concentrations were associated with metabolic disorder indexes and reduction of serum adiponectin. Our study demonstrates that untreated CAH patients are prone to have metabolic disorders in association with elevated serum testosterone levels and reduced insulin insensitivity.

Calcium channel blockers alter glucose homeostasis, but sufficient data regarding this effect in healthy animals have not been provided. We test the effect of nicardipine on cell function in healthy rats.

Abstract The comparative pollination biology of a population of Primula beesiana, a population of P. bulleyana, and an overlapping population of these two species in Yulong Shan, Yunnan Province, China, was studied in 2004 and 2005. The results indicate that both P. beesianaand P. bulleyanaare typical heterostylous and obligate outcrossing species; the main pollinators of the two species were bees and butterflies. At the sites of all three populations, the main pollinating visitors of the two species showed preference for one of the two species, resulting in the ethological isolation of the two species by the pollinators. This ethological isolation contributes to the reproductive isolation of the two species, which supports the hypothesis that P. beesianaand P. bulleyanaare two distinct species. The reproductive isolation of the two species (ethological isolation) is probably an important mechanism in maintaining species boundaries in the genus and has contributed to the species diversification of Primulain the area. In addition, gene exchanges between P. beesianaand P. bulleyanahas occurred to some extent in the overlapping population, but whether natural hybridization has contributed to species diversification in Primularemains to be determined.

Abstract The levels and partitioning of genetic diversity and inbreeding depression were investigated in Tupistra pingbianensis, a narrow endemic of southeast Yunnan, China, characterized by a naturally fragmented distribution due to extreme specialization on a rare habitat type. Here genetic diversity and patterns of genetic variation within and among 11 populations were analyzed using amplified fragment length polymorphism markers with 97 individuals across its whole geographical range. High levels of genetic variation were revealed both at the species level (P99= 96.012%; Ht= 0.302) and at the population level (P99= 51.41%; Hs= 0.224). Strong genetic differentiation among populations was also detected (FST= 0.2961; ?II= 0.281), which corresponded to results reported for typical animal-pollinated, mixed selfing, and outcrossing plant species. This result was consistent with mating patterns detected by our pollination experiments. The indirect estimate of gene flow based on ?IIwas low (Nm= 0.64). Special habitat and its life history traits might play an important role in shaping the genetic diversity and the genetic structure of this species. A pollination experiment also failed to detect significant inbreeding depression upon F1fruit set, seed weight, and germinate rate fitness-traits. As a naturally rare species, T. pingbianensisis not seriously genetically impoverished and likely to have adapted to tolerating a high level of inbreeding early in its history, we propose this species need only periodic monitoring to ensure their continued persistence, but not intervention to remain viable.

Parkinson's disease (PD) is a common neurodegenerative disease characterized by the selective loss of dopaminergic (DA) neurons in the midbrain. Various types of stem cells that have potential to differentiate into DA neurons are being investigated as cellular therapies for PD. Stem cells also secrete growth factors and therefore also may have therapeutic effects in promoting the health of diseased DA neurons in the PD brain. To address this possibility in an experimental model of PD, bone marrow-derived neuroprogenitor-like cells were generated from bone marrow procured from healthy human adult volunteers and their potential to elicit recovery of damaged DA axons was studied in a partial lesion rat model of PD. Following collection of bone marrow, mesenchymal stem cells (MSC) were isolated and then genetically modified to create SB623 cells by transient transfection with the intracellular domain of the Notch1 gene (NICD), a modification that upregulates expression of certain neuroprogenitor markers. Ten deposits of 0.5 μl of SB623 cell suspension adjusted from 6,000 to 21,000 cells/μl in PBS or PBS alone were stereotaxically placed in the striatum 1 week after the nigrostriatal projection had been partially lesioned in adult F344 rats by injection of 6-hydroxydopamine (6-OHDA) into the striatum. At 3 weeks, a small number of grafted SB623 cells survived in the lesioned striatum as visualized by expression of the human specific nuclear matrix protein (hNuMA). In rats that received SB623 cells, but not in control rats, dense tyrosine hydroxylase immunoreactive (TH-ir) fibers were observed around the grafts. These fibers appeared to be rejuvenated host DA axons because no TH-ir in soma of surviving SB623 cells or coexpression of TH and hNuMA-ir were observed. In addition, dense serotonin immunoreactive (5-HT-ir) fibers were observed around grafted SB623 cells and these fibers also appeared to be of the host origin. Also, in some SB623 grafted rats that were sacrificed within 2 h of dl-amphetamine injection, hot spots of c-Fos-positive nuclei that coincided with rejuvenated dense TH fibers around the grafted SB623 cells were observed, suggesting increased availability of DA in these locations. Our observations suggest that NICD-transfected MSC hold potential as a readily available autologous or allogenic cellular therapy for ameliorating the degeneration of DA and 5-HT neurons in PD patients.

Omphalogramma soulieiFranch. is an endangered perennial herb only distributed in alpine areas of SW China. ISSR markers were applied to determine the genetic variation and genetic structure of 60 individuals of three populations of O. soulieiin NW Yunnan, China. The genetic diversity at the species level is low with P=42.5% (percentage of polymorphic bands) and Hsp=0.1762 (total genetic diversity). However, a high level of genetic differentiation among populations was detected based on different measures (Nei's genetic diversity analysis: Gst=0.6038; AMOVA analysis: Fst=0.6797). Low level of genetic diversity within populations and significant genetic differentiation among populations might be due to the mixed mating system in which xenogamy predominated and autogamy played an assistant role in O. souliei.The genetic drift due to small population size and limited current gene flow also resulted in significant genetic differentiation. The assessment of genetic variation and differentiation of the endangered species provides important information for conservation on a genetic basis. Conservation strategies for this rare endemic species are proposed.

Pharmaceutical counterfeiting is becoming a significant issue in the healthcare community as well as for the pharmaceutical industry worldwide. A rapid screening technique such as near infrared (NIR) spectroscopy could aid in the search for and identification of counterfeit drugs. In the present paper, five generic vitamin tablets with different active ingredient content, produced by different manufacturers, were used as examples to test NIR spectroscopy for screening counterfeit products. The results showed that qualitative and quantitative NIR models of the generic drugs can be constructed, despite differences in formulation and physical properties of the tablets from the different manufacturers. In the case of the vitamin tablets, there is a high correlation between the spectra and the active ingredient content of the drug formulations. The differences in the active ingredients are significant enough to discriminate the tablets. Combining qualitative analysis with quantitative analysis further increases the effectiveness of NIR analysis. NIR spectroscopy offers an excellent opportunity for use as a screening technique to detect counterfeit samples.

Abstract Weedy rice refers to populations of usually annual Oryza species that diminish farmer income through reduction of grain yield and lowered commodity value at harvest. The genetic diversity and population genetic structure of weedy rice in Liaoning Province were studied by RAPD and SSR markers. The results indicate that the level of genetic diversity of Liaoning weedy rice is very low, with polymorphic loci being only 3.70% (RAPDs) and 47.62% (SSRs). On the other hand, high genetic differentiation was found among populations, in particular between two regions (Shenyang and Dandong), with Fst values of 0.746 (RAPDs) and 0.656 (SSRs), suggesting that more than two thirds of the genetic variation resides among regions. Combined with our investigations of cultural traditions, the low level of genetic diversity in Liaoning Province is attributed to its narrow genetic background enhanced by exchanges of cultivar seeds, whereas the high genetic differentiation between the two regions is most likely the result of different founding parents and gene flow from local rice varieties to weedy rice. The rice cultivars in the two regions are all local varieties and are different genetically. A comparison of the two marker systems demonstrates that SSR is more informative and powerful in terms of the assessment of genetic variability, although both RAPD and SSR provide useful genetic information on weedy rice.

The title Schiff base ligand, H2L, and its complex [CuL] have been prepared and characterized by elemental analysis and i.r. spectroscopy. The electrochemical properties of the single crystal [CuL]·0.5C2H4Cl2have been investigated by cyclic voltammetry (c.v.). Upon scanning at negative and positive potentials, two reduction and two oxidation waves were observed at E1/20= −0.47 and −0.77 V and E1/20= 1.10 and 1.39 V, respectively. Two Kcomvalues for the reduction and oxidation process are 1.2×105and 8.0×104, respectively, and indicate that the deprotonated ligand, L, has the ability to stabilize the mixed valent states of both CuIICuIand CuIICuIII. The crystal structure has been solved by X-ray diffraction, with a final R= 0.0653. Wound around a copper atom, the effectively tetradentate chain ligand, L, coordinates only viaits two imino and two phenolate groups at both ends of the chain. The geometry, D2dsymmetry, is best described as trans'N2O2' square-planar with slight tetrahedral distortion. The reason, why the mononuclear [CuL] unit can display two c.v. waves in each process, has been explained on the basis of configuration interchange between mono- and dinuclear units in c.v. electrolyte solution.

There are two peaks observed in the third-harmonic generation (THG) of polyacetylene. The first peak at 0.6 eV is a three-photon resonance enhancement due to the first one-photon excited state 11Bu. What's the nature of the second peak at 0.9 eV? Within an interacting-electron model, we investigated the excitonic states in conjugated polymers. Our calculation suggests that the second peak is a three-photon resonance enhancement due to the edge of the continuum excitation band.

The present study was undertaken to determinethe effect of tetramethylpyrazine administeredintraperitoneally on gastric lesions, gastric acidsecretion, gastric barrier mucus secretion, and gastriccontraction in reserpine-treated rats. The results of thisstudy demonstrated that tetramethylpyrazine at doses of0.5, 1, 10, and 20 mg/kg significantly inhibited theformation of gastric lesions induced by reserpine, with suppressive rates of 57.5%, 64.0%, 94.1%,and 96.0%, respectively. Tetramethylpyrazine (1 and 20mg/kg) significantly prompted the secretion of gastricbarrier mucus but had no effect on the secretion of gastric acid. Our findings also showed thattetramethylpyrazine (1 and 20 mg/kg) significantlysuppressed the frequency of gastric contractions, buthad no effect on the amplitude of gastric contraction. These results indicate that the protection oftetramethylpyrazine results, in part, from promotinggastric barrier mucus secretion and suppressing thefrequency of gastric contraction, but not fromsuppressing the secretion of gastric acid and the amplitudeof gastric contraction.

For one-dimensional conductors with half-filled band, the lattice vibration spectra, both acoustic and optical branches, are obtained analytically in the dimerized state. It is shown that, there exist not only a gap in Brillouin zone boundary, but also a gap between the optical and acoustic phonon branches when the electron-lattice coupling constant is Larger than . Then, the frequency of the Staggered mode around solitons can be described analytically for any coupling constant .

The exact static configuration of the soliton in polyacetylene is determined through the self-consistent iterations and the localized modes around the soliton are numerically calculated. They are compared with the results that the static configuration of the soliton is assumed to be the kink u0tanh(n/l). The comparison shows that the self-consistent configuration improves the Goldstone mode by getting the positive-definite vibrational matrix, whereas the other localized modes change their frequencies only less than 0.03%. It confirms that the five localized modes around the soliton do exist in polyacetylene.

MED20 is a non-essential subunit of the transcriptional coactivator Mediator complex, but its physiological function remains largely unknown. Here, we identify MED20 as a substrate of the anti-obesity CRL4-WDTC1 E3 ubiquitin ligase complex through affinity purification and candidate screening. Overexpression of WDTC1 leads to degradation of MED20, whereas depletion of WDTC1 or CUL4A/B causes accumulation of MED20. Depleting MED20 inhibits adipogenesis, and a non-degradable MED20 mutant restores adipogenesis in WDTC1-overexpressing cells. Furthermore, knockout of Med20in preadipocytes abolishes development of brown adipose tissues. Removing one allele of Med20in preadipocytes protects mice from diet-induced obesity and reverses weight gain in Cul4a-or Cul4b-depleted mice. Chromatin immunoprecipitation sequencing (ChIP-seq) analysis reveals that MED20 organizes the early adipogenic complex by bridging C/EBPβ and RNA polymerase II to promote transcription of the central adipogenic factor, PPARγ. Our findings have thus uncovered a critical role of MED20 in promoting adipogenesis, development of adipose tissue and diet-induced obesity.

Obesity has become a global pandemic. Identification of key factors in adipogenesis helps to tackle obesity and related metabolic diseases. Here, we show that DDB1 binds the histone reader BRWD3 to promote adipogenesis and diet-induced obesity. Although typically recognized as a component of the CUL4-RING E3 ubiquitin ligase complex, DDB1 stimulates adipogenesis independently of CUL4. A DDB1 mutant that does not bind CUL4A or CUL4B fully restores adipogenesis in DDB1-deficient cells. Ddb1+/−mice show delayed postnatal development of white adipose tissues and are protected from diet-induced obesity. Mechanistically, by interacting with BRWD3, DDB1 is recruited to acetylated histones in the proximal promoters of ELK1 downstream immediate early response genes and facilitates the release of paused RNA polymerase II, thereby activating the transcriptional cascade in adipogenesis. Our findings have uncovered a CUL4-independent function of DDB1 in promoting the transcriptional cascade of adipogenesis, development of adipose tissues, and onset of obesity.

The authors report the first ion implanted planar optical waveguide in the nonlinear and multifunctional crystal NdxY1-xAl3(BO3)4 (NYAB). The refractive index profiles are characterised for both no and ne. The index changes show that a typical barrier waveguide is formed in the implanted NYAB crystal and comparisons of the refractive index profiles before and after annealing are given. The damage in the crystal surface that was caused by the implantation of MeV He ions was investigated by using an RBS/channelling technique and there was some decrease in the damage of the surface of the crystal after annealing. The loss of the waveguide was measured before and after annealing.

of amphotericin B (5) (I)

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