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Micronsized spherical CL-20/RDX composites with uniform size were prepared by an electrospray method. After preparation, the morphology, crystal structure, thermal decomposition property, explosion performance and mechanical sensitivity were characterized. Different structures existed in the CL-20/RDX composites with different molar ratios. The CR11e composites had the lowest apparent activation energy and the lowest critical temperature of thermal explosion. The explosion pressure and mechanical sensitivity of CL-20/RDX composites were lower than that of raw CL-20 and decreased with increasing RDX content. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to explore the clinical benefits of establishing an enteral nutrition (EN) pathway via percutaneous transhepatic cholangiography drainage (PTCD) catheterization in patients with late-stage malignant obstructive jaundice (MOJ).Methods: We selected 30 patients diagnosed as having late-stage MOJ with malnutrition. A dual-lumen biliary-enteral nutrition tube was placed via PTCD along with a biliary stent implantation. Postoperative EN was provided, and we observed the time taken for tube placement, its success rate, complications, and therapeutic efficacy.Results: Tube placement was successful in all 30 patients with an average procedural time of 5.7 ± 1.4 min with no tube placement complications. Compared to preoperative measures, there was a significant improvement in postoperative jaundice reduction and nutritional indicators one month after the procedure (p < 0.05). Post-placement complications included tube perileakage in 5 cases, entero-biliary reflux in 4 cases, tube blockage in 6 cases, tube displacement in 4 cases, accidental tube removal in 3 cases, and tube replacement due to degradation in 8 cases, with tube retention time ranging from 42 to 314 days, averaging 124.7 ± 37.5 days. All patients achieved the parameters for effective home-based enteral nutrition with a noticeable improvement in their quality of life.Conclusion: In this study, we found that the technique of establishing an EN pathway via PTCD catheterization was minimally invasive, safe, and effective; the tube was easy to maintain; and patient compliance was high. It is, thus, suitable for long-term tube retention in patients with late-stage MOJ. [ABSTRACT FROM AUTHOR]

Inflammatory bowel disease (IBD) is a group of chronic intestinal inflammatory diseases with unknown etiology. Gap junctions composed of connexins (Cxs) have been recently validated as an important factor in the development of IBD. Under IBD-induced inflammatory response in the gut, gap junctions connect multiple signaling pathways involved in the interaction between inflammatory cells with other intestinal cells, which altogether mediate the development of IBD. This paper is a narrative review aiming to comprehensively elucidate the biological function of connexins, especially the ubiquitously and predominantly expressed Cx43, in the pathogenesis of IBD. [ABSTRACT FROM AUTHOR]

This study explores the current state-of-the-art in the detoxification and valorization of solid residues from municipal solid waste incineration (MSWI), especially fly ash, using plasma vitrification. The principles and advances in hazardous material elimination, resource recovery, and system integration using plasma vitrification for MSWI fly ash are identified. The global production and the characteristics of MSWI fly ash are first reviewed. Then, the features and principles of plasma technologies used for MSWI fly ash treatment from the thermodynamic and physical aspects are provided. The mechanisms of detoxification of MSWI fly ash from the perspectives of dioxins destruction and metal separation by plasma vitrification are also discussed. Moreover, the recovery methods of valuable elements for vitrified slag are introduced. Finally, the improvement pathways of plasma vitrification processes from the domains of engineering performance, environmental impact, and economic viability are suggested. [ABSTRACT FROM AUTHOR]

Soil microbes are an abundant source of enzymes with unique properties that may be useful for industrial applications. As most wild-type strains show low chlorogenic acid esterase expression and activity, and most microbes cannot be cultured in the laboratory, a metagenomic approach provides methods of identifying new enzymes. In this study, a gene encoding a chlorogenic acid esterase, named Tan410, was isolated from a soil metagenomic library and overexpressed in Escherichia coli BL21 (DE3). The recombinant enzyme, with a predicted molecular weight of 54.88 kDa, was purified to homogeneity. The Km and Vmax values for Tan410 were 1.26 mM and 0.33 mM min–1, respectively, with chlorogenic acid as the substrate. Its optimum temperature and pH for reaction were 30 °C and 7.5, respectively. The enzyme exhibited moderate thermostability and broad pH stability (3.0–10.0). Tan410 was also able to hydrolyse ethyl ferulate, methyl caffeate, propyl gallate, ethyl gallate, methyl vanillate, methyl benzoate, ethyl benzoate, methyl 2,5-dihydroxybenzoate, and methyl 3,5-dihydroxybenzoate, and it released caffeic and ferulic acids from agricultural byproducts (destarched wheat bran and coffee pulp). Tan140 has potential for industrial application in biomass valorization. [ABSTRACT FROM AUTHOR]

β-Thalassemia (β-thal) is one of the most common monogenic recessive inherited diseases worldwide. The mutation spectrum of β-thal has been increasingly broadened by various genetic testing methods. The discovery and identification of novel and rare pathogenic thalassemia variants enable better disease prevention, especially in high prevalence regions. In this study, a Chinese thalassemia family with an unclear etiology was recruited to the Thalassemia Screening Program. Blood samples collected from them were primarily screened by hematology analysis and clinical routine genetic screening. Subsequently, targeted next-generation sequencing (NGS) and Sanger sequencing were performed to find and identify a novel deletion variant. The deletion, discovered by targeted NGS, was validated through real-time quantitative polymerase chain reaction (qPCR). First, a large novel β-thal deletion (3488 bp) related to a high Hb F level, NC_000011.9: g.5245533_5249020del (Chongqing deletion) (GRCh37/hg19), was found and identified in the proband and her mother. The deletion removed the entire β-globin gene and led to absent β-globin (β0). We then validated this large novel deletion in the proband and her mother by qPCR. We first discovered and identified a large novel β-thal deletion related to elevated Hb F level, it helps broaden the spectrum of pathogenic mutants that may cause β-thal intermedia (β-TI) or β-thal major (β-TM), paving the way for effective thalassemia screening. Next-generation sequencing has the potential of finding rare and novel thalassemia mutants. [ABSTRACT FROM AUTHOR]

Currently, integrated navigation systems with the inertial navigation system (INS)/geomagnetic navigation system (GNS) have been widely used in underwater navigation of autonomous underwater vehicle (AUV). Restricting AUV to navigate in the geomagnetic suitability areas (GSA) as far as possible can effectively improve the accuracy of integrated navigation systems. In order to improve the classification accuracy of GSA, a new optimal classification method based on principal component analysis (PCA) and improved back propagation (BP) neural network is proposed. PCA is used to extract the independent characteristic parameters containing the main components. Then, considering similarity coefficient, the initial weights and thresholds of BP neural network is optimized by improved adaptive genetic algorithm (IAGA). Finally, the correspondence between the geomagnetic characteristic parameters and matching performance is established based on PCA and improved adaptive genetic algorithm and back propagation (IAGA-BP) neural network for the automatic recognition of GSA. Simulated experiments based on PCA and IAGA-BP neural network shows high classification accuracy and reliability in the GSA selection. The method could provide important support for AUV path planning, which is an effective guarantee for AUV high precision and long voyage autonomous navigation. [ABSTRACT FROM AUTHOR]

Early experiments have shown the promises of alloying with Mg + Ag (or Mg + Zn) on the performance of Al–Li alloys. To better understand the interaction between solutes and second phases in Al–Li alloys, Mg, Ag and Zn segregation to Al/δ′ interface as well as their substitution in δ′ bulk were investigated at the atomic level using first principles modelling and calculations. Energetics results and local charge analyses revealed that Mg, Ag and Zn can segregate to Al/δ′ interface by different preference, but have no significant influence on the interface adhesion. Ag and Zn can also dissolve into δ′ bulk, and enhance the local metallic bonding with nearest-neighboring Al atoms. Based on these results, a multi-fold benefit mechanism was suggested for the combined alloying with Mg + Ag (or Mg + Zn) in Al–Li alloys. [ABSTRACT FROM AUTHOR]

The production of high-modulus and high-strength polymer nanofibers using centrifugal or rotary jet spinning (RJS) was explored. Co-polyimide nanofibers based on 3,3′,4,4′-biphenyl-tetracarboxylic dianhydride (BPDA)/p-phenylenediamine (PDA)/4,4′-oxydianiline (ODA) (BPO) were successfully spun by RJS from a polyamic acid precursor solution before conversion into highly oriented and chain extended BPO co-polyimide fibers via an imidization step. Fourier transform infrared (FTIR) characterization was used to evaluate the chemical conversion of the fibers. Nanocomposite laminates based on co-polyimide nonwoven fiber mats in epoxy were manufactured for mechanical testing. Analysis using the generalized rule of mixtures resulted in a back-calculated fiber modulus and strength of around 50 and 2 GPa, approaching that of high-performance fibers like Kevlar® 29, and equaling those of co-polyimide fibers obtained via electrospinning, making them the strongest centrifugal spun fibers ever reported. [ABSTRACT FROM AUTHOR]

Experimental study of explosion prevention has been performed in the oil tank filled with suppression material. The kerosene in the pool is used as the fuel to ignite the gasoline and diesel oil tank to investigate the impact of suppression material on the degree of the deflagration. The pictorial information and temperature data are recorded by the high-speed camera and infrared imaging device, respectively. The maximum temperature of the fire in the tank within the filling material has apparently declined. The temperature of diesel oil liquid is greater than the diesel oil vapor. On the contrary, the temperature of gasoline vapor will keep arising and surpass the gasoline liquid. In the presence of suppression material, the average rate of temperature rise of the gasoline and diesel oil liquid is about 0.12 and 0.15 K/s, respectively. Damage of heat radiation effects to the human body from different combustion models has been compared with the effect of suppression material. [ABSTRACT FROM AUTHOR]

Pleistocene cave deposits usually provide ideal materials for the study of mammals. Karst caves in Chongzuo, Guangxi Zhuang Autonomous Region of south China are famous for numerous studies on their abundant mammalian fossils and most importantly, Homo sapiens. Unfortunately, the environmental backgrounds, e.g. vegetation and climate, that governed these faunas, are usually lacking because there is no appropriate proxy. In this work, we analysed the palynological assemblages from seven well-dated karst caves in Chongzuo. The ages of these seven caves (2.0–0.11 Ma) cover almost the entire Pleistocene. Though the number of pollen and spores is comparatively low, as expected, we managed to reconstruct the principle vegetation types. The results show that the individual vegetations were mainly warm temperate to subtropical evergreen and deciduous broad-leaved mixed forests. The present study provides important background environmental information on the Pleistocene faunas and Homo sapiens in Guangxi, south China. [ABSTRACT FROM AUTHOR]

Unmanned Aerial Vehicles (UAVs) are the most popular way to collect ground data today, thanks to their low cost and matchless convenience. However, UAVs are prone to unstable flight poses because they are so light in weight, which has resulted in a new challenge for UAV image stitching. In this paper, we propose a robust approach to stitch UAV images captured from approximately planar scenes without pose parameters assistance. The key idea of the proposed framework lies in an effective projection plane selection strategy, which is capable of resisting the perspective distortion from existing pose-perturbed images. To select a reasonable reference image as the projection plane, we first divide all the images into two groups (stable group and unstable group) according to their registration error under the affine model. Then, a specifically designed approach is used to define a weighted topological graph, which guarantees that the reference image is selected from the stable group while maintaining a global minimum accumulated registration error. Based on our cost topological graph, each unstable group image is locally attached to a stable group image via a homography. Finally, alignment parameters of all the stable group images are solved using affine model, after which global optimization is performed on the model of both groups. Comparing our results to those of the conventional approaches indicates that our proposed approach produced superior results in several challenging experiments involving both qualitative and quantitative evaluation. [ABSTRACT FROM AUTHOR]

Diffusion tensor imaging (DTI) measures the displacement of water molecules across tissue components and thus provides information on the microstructure of brain white matter. This study examined the effect of Tai Chi and the relation of Tai Chi experiences and skills with brain white matter. Fractional anisotropy (FA) was obtained from the DTI magnetic resonance images of two group participants, namely, the long-term Tai Chi practitioners and sedentary counterparts. Whole-brain voxel-based analysis showed that the Tai Chi group had higher FA in the splenium of corpus callosum (p = 0.015) than the control group. Rank correlation analysis revealed that in the Tai Chi group, the FA value of the splenium of corpus callosum was moderately related with exercise duration (r = 0.45, p = 0.045) but highly related with skill level (r = 0.699, p = 0.001). Long-term Tai Chi practice could benefit to the brain white matter, and these impacts were correlated with exercise duration and skill level. [ABSTRACT FROM AUTHOR]

With the aim to develop a predictive model to quantify shelf-life of yogurt, two yogurt samples were stored at various temperatures (5-35°C) and targeted for sensory assessment and evaluated using physicochemical, microbiological and sensory analysis. An increase in acidity and reduction in three parameters were observed with storage time, but the changes exhibited were relatively small at 5°C compared with the variation at higher temperatures. Our study developed a dynamic prediction model to determine the shelf-life of yogurt. Because of relatively small influence on shelf-life, microbiological data were excluded; thus, shelf-life of this product was established only based on remaining parameters. The results showed that shelf-life prediction was 15.5 and 18.5 days for sample 1 and 2 at 5°C, respectively. The prediction had a minute difference with the marked shelf-life which recognized Arrhenius model as an effective tool to predetermine the shelf-life and to improve the quality management of yogurt product. [ABSTRACT FROM AUTHOR]

Classification of 3D point cloud in urban scenes has been widely applied in the fields of automatic driving, map updating, and change detection. To develop the accurate and effective method for the classification remains a challenge. We propose a three-stage framework to classify 3D point clouds acquired in the urban road environment. First, an efficient segmentation approach is applied to generate segments as the entity to be classified. This is achieved by using the pairwise linkage (P-Linkage) algorithm for the initial point cloud segmentation, followed by two-step post-processing approach to improve the segmentation results. Second, a set of novel features is extracted from each segment and its performance is evaluated using four classifiers: Support Vector Machine, Random Forests, Naïve Bayesian, and Extreme Learning Machine. Third, the contextual constraints among objects are used to refine the classification via graph cuts. The results showed that the initial classification can obtain a high average precision of 80.8−92.9% and a good average recall rate of 77.5−79.1%. After refinement via graph cuts, the precision and recall rate increase by approximately 0.3% and 3.1%, respectively. Our framework is effective for classifying 3D urban point clouds acquired by a mobile laser scanning (MLS) system in the road environment. [ABSTRACT FROM AUTHOR]

China initiated a new round of science curriculum reform in 2017. Using the tripartite curriculum framework (including policy, programmatic, and classroom curriculum), we introduce and analyse China’s policy curriculum and programmatic curriculum for science in primary school and senior high school, and describe the potential problems hindering the translation of these curricula into the classroom curriculum. We first identify the multiple aims of different stakeholders in science education, some of which influence the science policy curriculum. Then, we present the major changes in how the programmatic curriculum meets the policy curriculum. However, due to extracurricular factors, the current science curriculum reform may not unfold as expected. We end with a discussion of the three major characteristics of the revision process of science curriculum standards in China, some of which might inform the global community of science education. [ABSTRACT FROM AUTHOR]

Lead was applied as an internal standard for the determination of Hg isotopic ratios. Cold vapor generation (CV) coupled with sector field-inductively coupled plasma-mass spectrometry (CV-SF-ICP-MS) was used for determination of Hg. It was effective to avoid interferences of Pb from samples while improving the sensitivity of Hg isotopic analysis by an approximate factor of 45 times higher than the aerosol mode. CV-SF-ICP-MS system was constructed and operational parameters were optimized. Research showed that the long stability of the system was limited by SF-ICP-MS and had no relationship with CV under the optimized conditions. The optimized precision of Hg isotopic ratio analysis was approximately 0.1% during 4 h. Five models were applied for the mass bias correction and the Baxter model obtained the smallest relative difference, 0.52‰. The results showed that the mean value of NIST SRM 3133 Hg isotopic ratios obtained by Pb internal standard was nearly identical with the value for Tl. The same performance was also obtained in two environmental reference materials. The results show that Pb may be used as the internal standard for determination of Hg isotopic ratio instead of Tl. [ABSTRACT FROM AUTHOR]

This paper presents an optimal seamline detection method for orthoimage mosaicking. To ensure that the detected optimal seamlines avoid crossing many obvious objects, we first design a simple but effective criterion in the gradient domain in lieu of the traditionally used intensity domain to measure the visibility of the seam. Thereafter, we fuse this new criterion into the graph cuts energy minimisation framework to globally find the last optimal seamlines. Instead of finding the optimal solutions of seamlines in overlap regions via graph cuts among the entire set of pixels, we first find them among superpixels created from input images and then refine them in the pixel level, which greatly improves the efficiency of the global graph cuts energy optimisation because the number of elements in graph cuts dramatically decreases. Experimental results on orthoimages show that our proposed method is capable of finding high-quality seamlines for orthoimage mosaicking, and outperforms state-of-the-art algorithms and software. [ABSTRACT FROM AUTHOR]

This article was an attempt to prepare energetic materials based on 1, 3, 5-trinitro-1, 3, 5-triazinane (RDX) using the electrospray method to expand its scope of application. After preparation, the morphologies and crystal structures of the samples were characterized, and thermal decomposition properties as well as mechanical sensitivities were also investigated. The sizes of the composite particles were found to be in the range of 2-4 μm. Compared with raw RDX, the crystal structures of the RDX/F2604 composites were unchanged. The activation energy of the composites was decreased with the increase of the F2604 mass ratio, and 10 wt% F2604 composites had the lowest activation energy. In the mechanical sensitivity aspect, the impact sensitivity and friction sensitivity of the RDX/F2604 composites were lower than those of raw RDX. 10 wt% F2604 composites had the highest H50 (65.9 cm) and the lowest friction sensitivity (76%). [ABSTRACT FROM AUTHOR]

This paper presents a revised learning progression for the energy concept and initial findings on diverse progressions among subgroups of sample students. The revised learning progression describes how students progress towards an understanding of the energy concept along two progress variables identified from previous studies – key ideas about energy and levels of conceptual development. To assess students understanding with respect to the revised learning progression, we created a specific instrument, the Energy Concept Progression Assessment (ECPA) based on previous work on assessing students’ understanding of energy. After iteratively refining the instrument in two pilot studies, the ECPA was administered to a total of 4550 students (Grades 8–12) from schools in two districts in a major city in Mainland China. Rasch analysis was used to examine the validity of the revised learning progression and explore factors explaining different progressions. Our results confirm the validity of the four conceptual development levels. In addition, we found that although following a similar progression pattern, students’ progression rate was significantly influenced by environmental factors such as school type. In the discussion of our findings, we address the non-linear and complex nature of students’ progression in understanding energy. We conclude with illuminating our research's implication for curriculum design and energy teaching. [ABSTRACT FROM PUBLISHER]

Rock extracts and oil samples has been detected high abundance of 18α(H)-neohopane fromYanchang Formation in Ordos Basin. The results showed that the black mudstone was deposited in anoxic condition of semi-deep or deep lacustrine facie has low abundance of 18α(H)-neohopane in Chang 7 member. The dark mudstones with high abundance of 18α(H)-neohopane in Chang 9 member that they were deposited in suboxic condition of shallow lacustrine facies. The origin of high concentration of 18α(H)-neohopane have relationship with the sedimentary environment and organic matter type. The geochemical significance of 18α(H)-neohopane can effectively solve the oil-source correlation of the research area. [ABSTRACT FROM PUBLISHER]

Two rare types of 4,6-dimethyl-3,4-dihydrochromen-2-one derivatives, named cralactones A and B (1and2), were isolated from the culture broth ofCraterellus odoratus. The structures of the new ones were established on the basis of extensive spectroscopic analysis, and it was found that the new compounds did not show pancreatic lipase inhibitory activity. Compounds1and2are the first examples of 4,6-dimethyl-3,4-dihydrochromen-2-one. [ABSTRACT FROM PUBLISHER]

This paper investigates the impact of manually operated solar shades on indoor thermal comfort. A developed stochastic model for manual solar shades was modelled in Building Controls Virtual Test Bed, which was coupled with EnergyPlus for co-simulation. Movable solar shades were compared with two unshaded windows (clear double-pane and low-e double-pane). Two objective indices (room base temperature and transmitted solar radiation) and one subjective index (modified predicted mean vote (PMV) index (PMVrad) that considers solar radiation on the human body) were used to evaluate the indoor thermal performance. Results show that external solar shades achieve the best performance in terms of all three indices, especially for PMVrad, hours of comfortable conditions are higher than unshaded windows by 20.6–37.3%. Despite achieving relatively high performance, solar shades are operated infrequently and for about 30% of work time they are not adjusted appropriately, leading to a decrease in indoor thermal comfort. [ABSTRACT FROM PUBLISHER]

This study examined the effects of regular Tai Chi (TC) exercise on the kinaesthesia of the knee and ankle joints of older women. A total of 43 women aged 55–68 years participated in this study. In a 24-week study period, the TC group (n = 22) underwent an organized TC exercise, whereas the control group (n = 21) maintained a sedentary lifestyle. Customized instruments were used to measure the threshold for the detection of the passive motion of the knee and ankle joints. After 24 weeks, the TC group showed a significantly smaller threshold for the detection of passive motion of knee extension (31.4%, p = 0.009), knee flexion (27.0%, p = 0.044), and ankle dorsal flexion (28.9%, p = 0.014) than the control group. Other comparisons showed no significant differences. The 24-week TC exercise benefited the lower-limb kinaesthesia of the knee joint flexion and extension and ankle dorsal flexion. [ABSTRACT FROM AUTHOR]

Unsatisfactory efficacy of clinical cure for long-term delayed injuries and other disadvantages such as the low regeneration rate and speed of axotomized neurons and the questionable reinnervation ability of atrophic target organ lead to inaction to the long-term delayed injuries. Here we attempted to use autologous nerve to bridge a long-term delayed 10-mm defect in SD rats based on some previous positive messages of basic and clinical research. In this study, for experimental groups, the rat sciatic nerve had been transected leaving a 10-mm defect, which was maintained for 3 or 6 months before implantation with the autologous graft. The non-grafted animals served as negative control. Measuring with electrophysiological and histological techniques, we find: (1) A number of long-term axotomized neurons survived and sustained certain degree of axonal regenerative capacity; (2) A few denervated Schwann cells survived and retained their ability to provide trophic support and myelinate axons in at least 6 months; (3) the chronically denervated muscle can partially be reinnervated by regenerated axons. But the quantity and the quality of the regenerated nerve fibers and the reinnervated muscle fibers were all poor. Thus these observations provide new positive morphological proof of nerve regeneration after long-term defects and further studies will be needed to increase the survival rate and the regenerative speed of long-term chronic axotomized neurons, enhance the support provided by denervated distal stumps and protect the target muscle. [ABSTRACT FROM AUTHOR]

This study examined the effects of 24 weeks of Tai Chi Quan on the postural control of elderly women. A total of 43 women aged 55–68 years participated in the study. A Tai Chi group (n = 22) underwent an organized Tai Chi exercise, whereas the control group (n = 21) maintained a habitual, no-regular-exercise lifestyle. A Good Balance tester (Metitur, Finland) was used to measure the time, paths and velocity of the center of pressure (COP) of subjects during stance while shifting COP to targeted positions shown on a monitor. After 24 weeks, the Tai Chi group showed significantly shorter total (18.6%,p= 0.005), mediolateral (21.9%,p= 0.002) and anteroposterior (18.3%,p= 0.002) COP sway paths than the control group. The results indicate that 24 weeks of the Tai Chi exercise improved the efficiency of postural control for elderly women. [ABSTRACT FROM PUBLISHER]

In this study, porous 316L deposits were processed by flame spraying under different spray conditions aimed at controlling deposit microstructure. Scanning electron microscopy (SEM) was used to characterize the microstructure of the deposits and deposit porosity was estimated from its cross section by image analysis. Results showed that porosity of 316L deposits ranged from 20 to 55% with change in spray particle melting degrees, resulting from alteration of spray parameters. To understand the deposition mechanism, the velocity of spray particles was quantitatively measured before impact and the morphology of isolated particles deposited was characterized by SEM and three-dimensional (3D) laser microscopy to estimate the melting degree of spray particles. The relationships between melting degree, spray conditions, and deposit porosity were established. The examination showed that porous steel deposits with 3D through-deposit pore-nets were fabricated through interbonding of solid cores of semimolten spray particles. It was found that the welding of particles by the molten fraction of semimolten spray particles forms large bonding necks between deposited particles, which improved the compression strength of the porous deposits over that fabricated by other conventional processes. [ABSTRACT FROM AUTHOR]

This article studies theory and inference of an observation-driven model for time series of counts. It is assumed that the observations follow a Poisson distribution conditioned on an accompanying intensity process, which is equipped with a two-regime structure according to the magnitude of the lagged observations. Generalized from the Poisson autoregression, it allows more flexible, and even negative correlation, in the observations, which cannot be produced by the single-regime model. Classical Markov chain theory and Lyapunov’s method are used to derive the conditions under which the process has a unique invariant probability measure and to show a strong law of large numbers of the intensity process. Moreover, the asymptotic theory of the maximum likelihood estimates of the parameters is established. A simulation study and a real-data application are considered, where the model is applied to the number of major earthquakes in the world. Supplementary materials for this article are available online. [ABSTRACT FROM AUTHOR]

For a multivariate linear model, Wilk's likelihood ratio test (LRT) constitutes one of the cornerstone tools. However, the computation of its quantiles under the null or the alternative hypothesis requires complex analytic approximations, and more importantly, these distributional approximations are feasible only for moderate dimension of the dependent variable, sayp≤20. On the other hand, assuming that the data dimensionpas well as the numberqof regression variables are fixed while the sample sizengrows, several asymptotic approximations are proposed in the literature for Wilk'sΛincluding the widely used chi-square approximation. In this paper, we consider necessary modifications to Wilk's test in a high-dimensional context, specifically assuming a high data dimensionpand a large sample sizen. Based on recent random matrix theory, the correction we propose to Wilk's test is asymptotically Gaussian under the null hypothesis and simulations demonstrate that the corrected LRT has very satisfactory size and power, surely in the largepand largencontext, but also for moderately large data dimensions such asp=30 orp=50. As a byproduct, we give a reason explaining why the standard chi-square approximation fails for high-dimensional data. We also introduce a new procedure for the classical multiple sample significance test in multivariate analysis of variance which is valid for high-dimensional data. [ABSTRACT FROM AUTHOR]

A body of evidence has suggested that tissue-engineered nerve grafts hold promise for the surgical repair of spinal cord injuries. In this study, a novel nerve graft was prepared to be implantated into a 5 mm gap which was caused by a complete transection of the rat spinal cord. The graft was featured by incorporation of neurotrophin-3 into a chitosan-based tube scaffold with a spinal cord-mimicking, partition-type architecture, which was prepared based on the morphometric insights of normal spinal cord anatomy. A set of behavioral, functional, and histological examinations were carried out to evaluate the repair. Results from Basso, Beattie, and Bresnahan tests, motor evoked potential measurements, anterograde tracing, and histological analyses suggested that the combined application of chitosan as the scaffold biomaterial, a spinal cord-mimicking partition-type as the scaffold archi tecture, and neurotrophin-3 (NT-3) as the bioactive component might probably create synergetic promotion on spinal cord regeneration. This composite nerve graft yielded significantly better results in axonal regeneration and function restoration as compared to its scaffold alone or other types of hollow tube scaffold alone. [ABSTRACT FROM AUTHOR]

For the sake of producing a giant magnetic moment in small manganese clusters, we have performed a density function theory calculation on MnNPd (N= 1–5) clusters. The results demonstrate that the doped -Pd atoms do not alter the basic framework, but significantly improve the average binding energy of host Mn clusters. The interaction among Mn atoms for MnNPd becomes weaker in comparison with corresponding MnNclusters which plays an important role in the appearance of giant magnetic moments of the system. Mn4Pd is the most promising in terms of gaining substantial binding energy as well as achieving larger ferromagnetic alignment (20μB). [ABSTRACT FROM AUTHOR]

Field survey of the entomopathogenic fungusBeauveria bassianain association with the red turpentine beetle,Dendroctonus valens, was undertaken in three pine plantations in Northern China. In total, 88 strains ofB. bassiana sensu latowere isolated from the soil, bark, beetle frass, living adult and cadaver samples and soil was proved to be an important inoculum reservoir for fungal entomopathogens. Of these, 77 isolates were included for genetic diversity analysis by PCR for inter-simple sequence repeats (ISSR). Genetic diversity and population structure analysis of the isolates from three sites and five niches demonstrated high genetic diversity and heterogeneity between and/or within populations. Wright's statistics revealed a high gene flow rate (4.529) among the three populations, especially among the soil-derived isolate subpopulations. Low variation was mainly caused (94.8%) by variation among different substrates, suggesting the importance of microhabitat substrates on genetic diversity ofB. bassiana. Phylogenetic variation was not associated with geographic distance. [ABSTRACT FROM AUTHOR]

A novel composite gel composed of carboxymethyl-chitosan (CM-chit) and bentonite (H-bent) was used as the carrier for encapsulating atrazine and imidacloprid to control their release in water and retard their leaching in soil. Strong interactions between CM-chit and H-bent in the composite were confirmed by FT-IR, and good dispersion of pesticides in the carrier was observed by SEM. According to the results of release experiments in water, the CM-chit/H-bent composite carrier showed double advantages of both encapsulation by the polymer and sorption by the bentonite. The time taken for 50 % of active ingredients to be released, t 50, was prolonged to 572 h for atrazine and 24 h for imidacloprid, respectively. The difference between the two pesticides on release behavior was related to their hydrophobicity and water solubility. Leaching experiments through a soil layer showed that this novel carrier reduced the amount of pesticides available for leaching, and would be useful for diminishing the environmental pollution of pesticides. [ABSTRACT FROM AUTHOR]

Two solvent-induced complexes, [CoL2(CH3OH)2] (1) and [CoL2(CH3CH2OH)2] (2), have been synthesized by the reaction of an oxime-type ligand (HL, 4-[(Ethoxyimino)(phenyl)methyl]-5-methyl-2-phenyl-1H-pyrazol-3(2H)-one) with cobalt(II) acetate tetrahydrate in different solvents. X-ray crystallographic analyses have indicated that complexes 1 and 2 have a similar structure, consisting of one CoII atom, two L− units, and two coordinated methanol or ethanol molecules. Interestingly, two CoII atoms in the structures of complexes 1 and 2 are all six-coordinated, approaching a staved octahedral geometry, but complexes 1 and 2 are grown up in methanol/chloroform and ethanol, respectively. Right because of this, solvent effect cause to the difference of the crystal structures: complex 1 forms an infinite supramolecular chain by intermolecular hydrogen bonds, while complex 2 exhibits three-dimensional supramolecular networks through intermolecular hydrogen bonds and C-H···π interactions. [ABSTRACT FROM AUTHOR]

Objective. Postoperative fatigue syndrome (POFS) is a general and main complication after surgery. However, there is no stable and standardized animal model for POFS. The aim of the present study was to establish a rodent model of POFS by small intestinal resection, with POFS evaluated by acknowledged physical and behavioral methods. Material and Methods. Forty-two Sprague-Dawley rats were randomly divided into four groups according to the length of a 'middle' small intestinal resection: 0% (sham group; i.e., laparotomy alone), 10%, 40% and 70% groups, with corresponding lengths of small intestinal resections. Following surgery, the general state of health was evaluated. Tail suspension test, open field test and Morris water maze test were used to evaluate the degree of POFS. Serum albumin, transferrin, prealbumin and fibronectin were measured to assess the nutritional status, and superoxide dismutase (SOD) and malondialdehyde (MDA) were also measured. Results. As compared with the other three groups, the 70% small intestinal resection group showed the worst general state of health, decreased strength of the tail suspension test and decreased score of Morris water maze test ( p < 0.05) after operation. All rats in whom the small intestinal resection was done demonstrated a certain degree of malnutrition and behavior of depression, and the 70% resection group had the lowest levels of transferrin, prealbumin and fibronectin as compared with the other groups ( p < 0.05), as well as decreased SOD and increased MDA in serum ( p < 0.05). Conclusions. Resection of 70% of the small intestine resulted in typical characteristics of POFS. As this procedure is simple, stable and easily reproducible, it may serve as a model for research on POFS. [ABSTRACT FROM AUTHOR]

Mn-doped scandium clusters have been systematically investigated using the density-functional approach. It was found that, starting from N = 6, the growth patterns of the ground-state structures of MnSc N clusters are dominated by octahedral structures with the Mn atom occupying the center of the host framework. The calculated results show that doping with Mn contributes to improving the stability of the scandium framework. The octahedral structure with the Mn atom occupying the center from N ≥ 6 has a relatively larger HOMO–LUMO gap compared with small-sized MnSc N clusters. Also, the largest oscillation of the energy gap occurs at N = 5 and 6. Moreover, the local peaks of N = 3, 5 and 8 of the energy gap are in agreement with the second-order energy differences. The encapsulated Mn atom, coupled with the antiferromagnetic alignment with N ≥ 6, reduces the magnetism of the host Sc N clusters in most cases. This is different from Mn doped into B n , Ge n , and Bi n clusters. The MnSc6 cluster not only has the smallest energy gap (about 0.01 eV), but also the largest magnetic moment of 5 µB of all of the MnSc N clusters. [ABSTRACT FROM AUTHOR]

Objective. Our aim was to investigate the effect of soy isoflavone (SI) on liver fibrosis in a thioacetamide (TAA)-induced rat model. Materials and methods. Twenty-eight rats were assigned to four groups: sham group, fibrosis group, low-dose treatment group (LDg) and high-dose treatment group (HDg). SI (90 or 270 mg/kg) was administered daily during the model development by TAA. Standard liver tests, platelet derived growth factor-BB (PDGF-BB) and tissue inhibitor of metalloproteinase-1 (TIMP-1) were measured. The expression of collagen, αα-smooth muscle actin (αα-SMA) and transforming growth factor-ββ1 (TGF-ββ1) in liver tissue was determined. Electron microscopy was used to perform ultrastructural analysis of the livers. Results. Hepatic fibrosis was induced by 8 weeks of TAA administration. However, following the administration of SI, collagen staining significantly declined as compared with the fibrosis group ( p < 0.01). Less collagen fibers around the hepatic stellate cells (HSCs) were observed in HDg as compared to the fibrosis group and LDg. There was no significant difference in standard liver tests between the fibrosis group and the two treatment groups. The levels of PDGF-BB and TIMP-1 in the two SI-treated groups were significantly lower than in the fibrosis group ( p < 0.01). The expression of αα-SMA and TGF-ββ1 in HDg was less than that in the fibrosis group and LDg ( p < 0.01). Conclusion. Administration of a high dose of SI resulted in an obvious inhibitory effect on liver fibrosis induced by TAA in rats. One hypothesis is that the effect may be related to the inhibition of HSC activation and proliferation. [ABSTRACT FROM AUTHOR]

A new Co(II) cluster, {[CoL(DMF)]2(OAc)2Co}·2DMF (H2L = 4,4'-dichloro-2,2'-[(1,3-propylene)dioxybis (nitrilomethylidyne)]diphenol), has been synthesized and characterized by elemental analysis, IR spectrum, UV-Vis spectrum, and X-ray diffraction method. The results indicate that the Co(II) cluster consists of three Co(II) ions, two tetradentate (μ-L)2- units, two coordinated μ-acetate ions, two coordinated DMF, and two crystallizing DMF molecules. All the hexa-coordinated Co(II) ions of the Co(II) cluster have a slightly distorted octahedral geometry. The crystal packing of the Co(II) cluster shows that a notable feature of this structure resides in the formation of a novel 2D supramolecular structure through intermolecular C-H···O interaction and weak intramolecular C-H···(Ph) interaction along the b-axes. [ABSTRACT FROM AUTHOR]

The characteristics of a highly sensitive terahertz wave detector based on lithium niobate have been investigated using a steady-state theory. The contributions of the low-frequency modes to the dielectric constant of lithium niobate are considered. The intrinsic factors of the LN detector limit its high frequency response to about 4 THz. Temperature dependence of the detector from room temperature to 250°C was also studied. The main factors associated with the temperature variations of the sensitivity of the detector are thermal expansion, the nonlinear coefficient and the refractive index of the crystal. The nonlinear coefficient dominates the temperature dependence of the sensitivity of the detector, while the impact of the refractive indices of the near-infrared lights on the temperature variation of the sensitivity of the detector is negligible. This study provides a useful guide and a theoretical basis for the further improvement of the detection systems. [ABSTRACT FROM AUTHOR]

[image omitted]Five novel nonenolides, phomolides D-H (1-5), and phomonol (6), phomotone (7) and phomopene (8), plus previously know compounds 4-formyl-7-methoxyl-6-methyl-phthalide (9), dihydrogladiolic acid methyl lactal (10), cytochalasin H (11) and cytochalasin J (12) were isolated from the endophytic fungal strain Phomopsis sp. A123. This strain was isolated from leaves of the mangrove species, Kandelia candel, collected in the Fugong Mangrove Conservation Area, Fujian, China. The chemical structures were elucidated by spectroscopic analyses, including 1D- and 2D-NMR, and on the basis of HR-Q-TOF mass spectrometry. Antibacterial assays with the novel compounds 1-8 were carried out; they had no effect on the growth of the tested bacteria or yeasts. [ABSTRACT FROM AUTHOR]

Two new complexes, [Cu(L1)2] (1) and [Cu(L2)2(H2O)]·CH3OH (2), have been synthesized via the complexation of copper(II) acetate monohydrate with two mono-oxime chelating ligands (HL1: 4-[(Methoxyimino)(phenyl)methyl]-5-methyl-2-phenyl-1H- pyrazol-3(2H)-one and HL2: 4-[(Ethoxyimino)(phenyl)methyl]-5-methyl-2-phenyl-1H-pyrazol-3(2H)-one), respectively. X-ray crystal structure determination of the two complexes show that complex 1 consists of one copper(II) ion, two bidentate (L1)- units, and the copper atom of complex 1 has a square planar geometry distorted tetrahedrally with four-coordination, while complex 2 consists of one copper(II) ion, two bidentate (L2)- units, one coordinated H2O, and one crystallizing methanol molecule, as expected from the analytical data. And the copper atom of complex 2 has a slightly distorted tetragonal pyramid geometry with five-coordination. Complex 2 is a self-assembling infinite chain supramolecular structure formed by intermolecular hydrogen bonds. Meanwhile, the photophysical properties of the resulted complexes have also been discussed. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the feasibility of using tissue-engineered nerve grafts for delayed repair of peripheral nerve defects. A 1-month delayed, 10-mm long sciatic nerve defect was created for rats, which were divided into three grafted groups and a non-grafted group. For bridging the nerve defects, the rats in three grafted groups were subjected to surgical repair with tissue-engineered nerve grafts made of a chitosan/polyglycolic acid (PGA) conduit filled with neural stem cells (NSCs), chitosan/PGA conduits, and autologous nerve grafts, respectively. At 3 months after nerve grafting, the data from electrophysiology, retrograde tracing and histological investigation revealed that the better outcomes in sciatic nerve regeneration and target muscle re-innervation were achieved in three grafted groups as compared to those in non-grafted group without major differences between three grafted groups. Our results suggest that grafting of chitosan/PGA conduits might be a promising technique for repairing peripheral nerve injuries after a 1-month delay, while introduction of NSCs seem to show no significant additional benefits to regenerative outcomes. [ABSTRACT FROM AUTHOR]

In this study, we evaluated the effect of the application by two agrochemicals, methamidophos (O,S-dimethyl phosphoroamidothioate) and urea, on microbial diversity in soil, using the combined approaches of soil microbial biomass analysis and community level physiological profiles (CLPPs). The results showed that both a low and a high level of methamidophos application (CS2 and CS3) and urea application (CS4) significantly decreased microbial biomass C (C mic ) by 41–83% compared with the control (CS1). The soil organic C (C org ) values of CS3 and CS4 were significantly higher and lower by 24% and 14%, respectively, than that of CS1. Similarly to C mic , the values of C mic /C org of the three applied soils which decreased were lower by 31–84% than that of CS1. In contrast, the respiration activity of the three applied soils were significantly higher than the control. Agrochemical application also significantly increased the soil total of N and P (N tol and P tol ) and decreased the C org /N tol and C org /P tol values. The CLPPs results showed that the AWCD (average well color development) of the three applied soils were significantly higher than that of CS1 during the incubation period. Substrate richness, Shannon and Simpson indices of microbial communities under chemical stresses, increased significantly. In addition, the CFU (colony-forming unit) numbers of methamidophos metabolized bacteria in CS2 and CS3 also increased significantly by 86.1% and 188.9% compared with that of CS1. The combined results suggest that agrochemicals reduce microbial biomass and enhance functional diversities of soil microbial communities; meanwhile, some species of bacteria may be enriched in soils under methamidophos stress. [ABSTRACT FROM AUTHOR]