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The mutual optical intensity (MOI) model is a partially coherent radiation propagation tool that can sequentially simulate beamline optics and provide beam intensity, local degree of coherence and phase distribution at any location along a beamline. This paper extends the MOI model to non-ideal two-dimensional (2D) optical systems, such as ellipsoidal and toroidal mirrors with 2D figure errors. Simulation results show that one can tune the trade-off between calculation efficiency and accuracy by varying the number of wavefront elements. The focal spot size of an ellipsoidal mirror calculated with 100 × 100 elements gives less than 0.4% deviation from that with 250 × 250 elements, and the computation speed is nearly two orders of magnitude faster. Effects of figure errors on 2D focusing are also demonstrated for a non-ideal ellipsoidal mirror and by comparing the toroidal and ellipsoidal mirrors. Finally, the MOI model is benchmarked against the multi-electron Synchrotron Radiation Workshop (SRW) code showing the model's high accuracy. [ABSTRACT FROM AUTHOR]

Combining wave optics propagation and geometric ray tracing, the mutual optical intensity (MOI) model is extended to quantitatively simulate the propagation of partially coherent light through a kinoform lens at high speed. The MOI model can provide both a high accuracy and a high efficiency simulation. The intensity and coherence degree distributions at the focal plane are calculated using the MOI model. It is beneficial to improve the focusing capability of the kinoform lens by reducing the coherence or increasing the number of lens steps. In addition, increasing the number of steps is also beneficial to increase the photon flux and reduce the depth of focus. [ABSTRACT FROM AUTHOR]

Combining geometric ray tracing and wave optics propagation, a new simulation model named LWF is established to calculate the full coherent X-ray propagation through a kinoform lens. The LWF model is used to analyze the X-ray propagation through long and short kinoform lenses and calculate the intensity distribution at the focal plane. When the aperture is large, the focal spot for the long kinoform lens is smaller than that for the short kinoform lens. Due to the use of the geometric ray-tracing method to calculate the beam propagation inside the kinoform lens, the LWF model takes a low number of transversal wavefront segments, i.e. a short time, to achieve high accuracy. The simulation times for the one-dimensional and two-dimensional LWF models are 0.025 s and 5.3 s, respectively, with a calculation error of less than 0.5%. The high efficiency and high accuracy make the LWF model a strong tool in designing kinoform lenses. [ABSTRACT FROM AUTHOR]

It has been found that fibroblast growth factor receptor (FGF-FGFR) signaling can regulate the expression of adipocyte differentiation genes. FGF9 is one of the members of FGFs that mainly binds receptors FGFR2 and FGFR3. FGF9 is highly expressed in the adipose tissue of humans and mice, but there are few reports on the role of FGF9 in goat intramuscular adipocyte differentiation. Therefore, this study explored the effect of FGF9 on adipocyte differentiation through cell culture, interference, and overexpression. The expression of receptors FGFR1-FGFR4 in adipocyte differentiation and their effects on differentiation were detected to screen receptor gene of FGF9. Finally, the interaction between FGF9 and the receptor was tested by cotransfection. Our results showed that FGF9 interacts with FGFR2 to inhibit goat intramuscular adipocyte differentiation by regulating peroxisome proliferatoractivated receptor gamma (PPARγ) and preadipocyte factor 1 (Pref1), which is a data support for subsequent pathway research. [ABSTRACT FROM AUTHOR]

Previous research reported that KLF3 plays different roles in the regulation of adipose deposition across species. However, the exact function of KLF3 in goat subcutaneous adipocyte remains unknown. Here, the goat KLF3 gene was firstly cloned and showed that the mRNA sequence of the goat KLF3 gene was 1,264 bp (GenBank accession number: KU041753.1) and its coding sequence was 1,037 bp, encoding 345 amino acids with three classic zinc finger domains of KLFs family at its C-terminus. The alignment of the amino acid sequence of KLF3 among various species demonstrated that goat had the highest homology to that of sheep, presenting 99.4% similarity, while the homology similarity to that of mice presented only 93.62% in contrast. Furthermore, KLF3 had highest mRNA level in fat tissue and lowest level in the heart in comparison. Additionally, the mRNA level of KLF3 gradually tended to increase during adipogenesis. Interestingly, overexpression of KLF3 increased lipid accumulation. In line with this, the gain-of-function of KLF3 dramatically elevated the mRNA levels of TG synthetic genes and adipogenic maker genes (p < .01). Moreover, overexpression of KLF3 upregulated all the potential target genes, except for C/EBPa. These results suggested that KLF3 is a positive regulator for subcutaneous adipocyte differentiation in goats. [ABSTRACT FROM AUTHOR]

Indoor navigation networks serve as the foundation for indoor pedestrian navigation services. However, current graph-based topological network models cannot easily represent complex indoor structures in a manner consistent with user behaviour and cognitive patterns, and thus cannot support fine-grained indoor navigation analysis services. To enhance the rationality of the model, we considered the influences of morphological and functional characteristics of indoor spaces on pedestrian movement and proposed a method for classifying navigation spaces. This method, based on convex space segmentation, defines morphological and functional characteristic functions, classifying indoor navigation spaces as either corridors or open spaces, which suitable for representing as median axis models or visual graphs, respectively. These categories supported the creation of topological network models for route planning analysis. Indoor map experiments confirmed the effectiveness of our method in identifying various types of corridors and open spaces, that addressing the limitations of width-based parameters, even in complex indoor settings. [ABSTRACT FROM AUTHOR]

Alkynones represent one class of interesting building block which are frequently founded in a variety of biologically active compounds.[1] They have been emerged as key intermediates in the synthesis of various natural products and heterocycles.[2] Therefore, a considerable interest has been attracted and numerous strategies have been explored for the synthesis of alkynones. The traditional methods mainly rely on the reactions of acid chlorides with terminal alkynes.>[3–4] However, some drawbacks remain existing, including high reaction temperature, unstable acid chlorides, and poor functional group tolerance. [ABSTRACT FROM AUTHOR]

Blood-brain barrier (BBB) disruption plays a critical role in brain injury induced by cerebral ischemia, and preserving BBB integrity during ischemia could alleviate cerebral injury. We examined the role of miR-130a in ischemic BBB disruption by using models of rat middle cerebral artery occlusion and cell oxygen-glucose deprivation. We found that ischemia significantly increased microRNA-130a (miR-130a) level and that miR-130a was predominantly from brain microvascular endothelial cells. Antagomir-130a, an antagonist of miR-130a, could attenuate brain edema, lower BBB permeability, reduce infarct volume, and improve neurologic function. MiR-130a overexpression induced by miR-130a mimic increased monolayer permeability, and intercellular inhibition of miR-130a by a miR-130a inhibitor suppressed oxygen-glucose deprivation-induced increase in monolayer permeability. Moreover, dual luciferase reporter system showed that Homeobox A5 was the direct target of miR-130a. MiR-130a, by inhibiting Homeobox A5 expression, could down-regulate occludin, thereby increasing BBB permeability. Our results suggested that miR-130a might be implicated in ischemia-induced BBB dysfunction and serve as a target for the treatment of ischemic stroke. [ABSTRACT FROM AUTHOR]

This Letter proposes a read-decoupled (RD) and average 8T1R non-volatile static RAM(SRAM), RD-8T1R. It uses only one memristor to achieve 2× store energy reduction and higher restore yield compared with other two memristors based non-volatile SRAMs. In addition, this structure can offer two alternative SRAM modes unlike previously known non-volatile SRAMs, i.e. a high speed and a stable mode. Compared with existing technologies, the simulation results in TSMC-65 nm show that the proposed scheme provides a remarkable restore yield. There are ~154% improvement in the read static noise margin (@typical–typical (@TT) corner and stable mode) and ~23% improvement in the read delay (@TT corner and high speed mode) compared with the previous 6T/7T/8 T non-volatile SRAMs. [ABSTRACT FROM AUTHOR]

Three-phase NaCl-H2O fluid inclusions featuring halite dissolution temperature ( Tm) higher than vapor bubble disappearance temperature ( Th) are commonly observed in porphyry copper/molybdenum deposits, skarn-type deposits and other magmatic - hydrothermal ore deposits. Based on | ΔV1| (the absolute value of volume variation of NaCl-H2O solution in a heating or cooling process of inclusions)= | ΔVs| (the absolute value of volume variation of the halite crystal in a heating or cooling process of inclusions) and on the principle of conservation of the mass of NaCl and H2O, we systematically calculated the densities of NaCl-H2O solutions in the solid-liquid two-phase field for temperatures ( Th) from 0.1°C to 800°C and salinities from 26.3 wt% to 99.2wt%. Consequently for the first time we obtained the upper limit of the density of NaCl-H2O solutions in the solid-liquid two-phase field for Th< Tm inclusions with variant salinities. The results indicate that for inclusions of the Th< Tm type with the same Th, the higher the Tm or salinity is, the higher the density of the NaCl-saturated solution will be. If a group of fluid inclusions were homogeneously trapped, they must have the same Th value and the same Tm or salinity value. This may be used to distinguish homogeneous, inhomogeneous, and multiple entrapments of fluid inclusions. [ABSTRACT FROM AUTHOR]

Complete neighbourhood preserving embedding (CNPE) is a recently proposed approach to overcome the drawbacks of neighbourhood preserving embedding (NPE) which is difficult to directly apply to face recognition because of computational complexity. However, there are still disadvantages for CNPE: (i) CNPE is time-consuming when N is large, here N is the sample size; (ii) the solutions of CNPE may suffer from the degenerate eigenvalue problem, that is, several eigenvectors with the same maximal eigenvalue, which make them not optimal in terms of the discriminant ability. In this study, the authors proposed a new approach, namely improved complete neighbourhood preserving (ICNPE), to address the drawbacks of CNPE. ICNPE is more efficient than CNPE and can overcome the degenerate eigenvalue problem of CNPE. Experiments on the Olivetti & Oracle Research Laboratory (ORL), Yale, PIE (pose, illumination and expression) and Alex Martinez and Robert Benavente (AR) face databases show the effectiveness of the proposed ICNPE. [ABSTRACT FROM AUTHOR]

Objective: The aims of this study were to confirm whether traditional Chinese medicine ginsenoside Rb1 (Rb1), ginsenoside Rg1 (Rg1), polygonum multiflorum (PM), ginkgo extract (GE) and lycium barbarum polysaccharide (LBP) can attenuate G1 growth arrest of HaCaT cells and dermal fibroblasts induced by 10 subcytotoxic ultraviolet B (UVB) exposures, and to explore the possible mechanism in terms of the expression of cell-cycle regulatory proteins p16, p21 and p53. Methods: Ten subcytotoxic exposures to UVB induced G1 growth arrest of HaCaT cells and dermal fibroblasts. Cell-cycle analysis was performed using flow cytometry, and mRNA levels of p16, p21 and p53 were detected by a reverse transcription-polymerase chain reaction (RTPCR), and protein levels were detected using Western blot analysis. Results: Five types of traditional Chinese medicine attenuated UVB-induced G1 growth arrest. The mRNA and protein levels of p16, p21 and p53 in HaCaT cells and dermal fibroblasts increased after UVB irradiation, but pretreatment with five types of traditional Chinese medicine decreased the expression of p16, p21 and p53. Conclusions: These results indicated that five types of traditional Chinese medicine can attenuate G1 growth arrest of HaCaT cells and dermal fibroblasts induced by UVB exposures, which was caused by down-regulating the expression of cell-cycle regulatory proteins p16, p21 and p53. [ABSTRACT FROM AUTHOR]

Cuttings of Populus kangdingensis C. Wang et Tung and Populus cathayana Rehder were examined during a single growing season in a greenhouse for comparative analysis of their physiological and proteomic responses to drought stress. The said species originate from high and low altitudes, respectively, of the eastern Himalaya. Results revealed that the adaptive responses to drought stress vary between the two poplar species. As a consequence of drought stress, the stem height increment and leaf number increment are more significantly inhibited in P. cathayana compared with P. kangdingensis. On the other hand, in response to drought stress, more significant cellular damages such as reduction in leaf relative water content and CO2 assimilation rate, increments in the contents of malondialdehyde and hydrogen peroxide and downregulation or degradation of proteins related to photosynthesis occur in P. cathayana compared with P. kangdingensis. On the other hand, P. kangdingensis can cope better with the negative impact on the entire regulatory network. This includes more efficient increases in content of solute sugar, soluble protein and free proline and activities of antioxidant enzymes, as well as specific expressions of certain proteins related to protein processing, redox homeostasis and sugar metabolism. Morphological consequences as well as physiological and proteomic responses to drought stress between species revealed that P. kangdingensis originating from a high altitude manifest stronger drought adaptation than did P. cathayana originating from a low altitude. Functions of various proteins identified by proteomic experiment are related with physiological phenomena. Physiological and proteomic responses to drought stress in poplar may work cooperatively to establish a new cellular homeostasis, allowing poplar to develop a certain level of drought tolerance. [ABSTRACT FROM AUTHOR]

Although effects of forest management on amphibians are relatively well studied, few studies have examined how these practices affect egg deposition by adults, which can impact population recruitment. We quantified the effects of 4 canopy tree-retention treatments on amphibian oviposition patterns in clusters of 60-L aquatic mesocosms located in each treatment. We also related aquatic and terrestrial biophysical parameters in treatment plots to oviposition patterns. Cope's gray treefrogs (Hyla chrysoscelis) deposited more egg masses in clear-cut and 25-50% tree-retention treatments than in controls. In contrast, mountain chorus frogs (Pseudacris brachyphona) deposited more egg masses in unharvested control and 75% retention treatments than in clear-cut or 25-50% retention treatments. Spotted salamanders (Ambystoma maculatum) only deposited eggs in 75% retention treatments and controls. The number of egg masses deposited by mountain chorus frogs was positively related to canopy cover and negatively related to water temperature, pH, and dissolved oxygen, whereas we noted the opposite relationships for Cope's gray treefrogs. We did not detect a relationship between the number of egg masses deposited by any species and the distance of mesocosms to either the nearest mature closed-canopy forest or to the nearest natural amphibian breeding pool. The impacts of the silvicultural treatments we studied were species-specific and depended on the amount of trees removed. In areas where protection of spotted salamander and mountain chorus frog breeding habitat is a priority, we recommend harvests retain at least 75% of the canopy. Our results also suggest that retention of 25-50% of canopy trees surrounding amphibian breeding pools has little conservation benefit. [ABSTRACT FROM AUTHOR]

Myricaria species in China occur mostly in the major high-altitude mountain areas in and around the Qinghai-Tibetan Plateau. The one major exception to this is M. laxiflora which is restricted to the Three Gorges mountain region. In this study, we investigate species-level phylogeographical patterns of Myricaria species in western China and the origin of M. laxiflora. The results show that most chloroplast haplotypes are species-specific, except for one haplotype which is shared by three widespread species. Higher haplotype diversity within the Qinghai-Tibetan Plateau region supports the hypothesis that the Himalayas are the centre of origin for Myricaria. The phylogeny of Myricaria was geographically structured, and an estimated Bayesian chronology suggested the main divergence events occurred during the Late Pliocene and Early Pleistocene (~1.46–2.30 million years ago). The overall phylogeographical pattern was characterized by vicariance events and regional demographical expansion, reflecting a major influence of geological and climatic events on the evolution of Myricaria species. Our data suggest that M. laxiflora has an ancient origin, but has experienced recent population expansion through the Three Gorges Valley. The origin of M. laxiflora was estimated to be during the Early Pleistocene but its demographical expansion was more recent at about 0.015 million years ago. This highlights the unique phylogeographical history of the Three Gorges mountain region, and the deep imprint of the watercourse connections of the Yangtze River Valley on the phylogeographical structure of the species in this region. [ABSTRACT FROM AUTHOR]

Heterologous biosynthesis offers a new way to capture the medicinal properties presented by complex natural products. In this study, production of 6-deoxyerythronolide B (6dEB), the polyketide precursor to the antibiotic erythromycin, was used to probe the heterologous pathways needed for Escherichia coli-derived biosynthesis. More specifically, the heterologous proteins responsible for 6dEB production were varied by adjusting their respective gene dosage levels. In this way, heterologous components required for posttranslational modification, 6dEB biosynthesis, and substrate provision were adjusted in expression levels to observe the relative effect each has on final heterologous biosynthesis. The results indicate that both the biosynthetic and substrate provision heterologous proteins impact 6dEB formation to a greater extent when compared with posttranslational modification and suggest these components for future protein and metabolic engineering. [ABSTRACT FROM AUTHOR]

The inverted repeats present in a genome play dual roles. They can induce genomic instability and, on the other hand, regulate gene expression. In the present study, we report the distribution and sequence features of recombinogenic long inverted repeats (LIRs) that are capable of forming stable stem-loops or palindromes within the human genome. A total of 2551 LIRs were identified, and 37% of them were located in long introns (largely > 10 kb) of genes. Their distribution appears to be random in introns and is not restrictive, even for regions near intron–exon boundaries. Almost half of them comprise TG/CA-rich repeats, inversely arranged Alu repeats and MADE1 mariners. The remaining LIRs are mostly unique in their sequence features. Comparative studies of human, chimpanzee, rhesus monkey and mouse orthologous genes reveal that human genes have more recombinogenic LIRs than other orthologs, and over 80% are human-specific. The human genes associated with the human-specific LIRs are involved in the pathways of cell communication, development and the nervous system, as based on significantly over-represented Gene Ontology terms. The functional pathways related to the development and functions of the nervous system are not enriched in chimpanzee and mouse orthologs. The findings of the present study provide insight into the role of intronic LIRs in gene regulation and primate speciation. [ABSTRACT FROM AUTHOR]

Mitochondrial dysfunction is implicated in the pathogenesis of diabetic cardiomyopathy, a common complication of diabetes. Adenosine nucleotide translocase (ANT) translocates ADP/ATP across the inner mitochondrial membrane. Our study aimed to test the hypothesis that overexpression of ANT1 in cardiomyocytes has cardioprotective effects in diabetic cardiomyopathy induced by streptozotocin (STZ). Mice specifically overexpressing murine ANT1 in the heart were generated using α-myosin heavy chain promoter. Expression of ANT1 mRNA and protein in hearts was characterized by real-time polymerase chain reaction and Western blot analysis. Five- to 6-month-old male transgenic mice and their age-matched wild-type littermates were subjected to type 1 diabetes induced by STZ. Six weeks later, haemodynamic measurement was performed to assess cardiac function. Ventricular mRNA expression of atrial natriuretic peptide, a molecular marker of heart failure, was characterized by RNase-protection assay. Both ANT1 mRNA and ANT1 protein were specifically overexpressed in the heart of transgenic mice. Heart weight was decreased and cardiac function was dramatically impaired in wild-type mice 6 weeks after induction of diabetes, but ANT1 overexpression prevented these significant changes. The mRNA expression level of atrial natriuretic peptide confirmed the haemodynamic findings, being upregulated in wild-type mice receiving STZ, but showing no statistical differences in ANT1 transgenic mice. Cardiomyocyte-restricted overexpression of ANT1 prevents the development of diabetic cardiomyopathy; therefore, accelerated ADP/ATP exchange could be a new promising target to treat diabetic cardiomyopathy. [ABSTRACT FROM AUTHOR]

Background and Aims: Development of an accurate and less cumbersome noninvasive method to detect current Helicobacter pylori infection is essential in clinic. The aim of this study was to evaluate the performance of the CIM test, also known as the Assure® H. pylori Rapid Test (Genelabs Diagnostics Pty. Ltd., Singapore), for the diagnosis of current H. pylori infection before and after eradication therapy in Chinese population. Methods: A total of 452 eligible people were recruited for this study in Jiangsu Province, China. Each individual underwent a 13C urea breath test (13C-UBT). For the evaluation of CIM test after eradication, 115 H. pylori-positive outpatients were treated with 1-week triple therapy. One month after the end of therapy, the patients underwent 13C-UBT again, and the CIM-test was performed 1, 3, and 6 months after the end of therapy. Its performance (sensitivity, specificity, positive and negative predictive values, and accuracy) were determined using the 13C-UBT as a gold standard for H.  pylori diagnosis. Results: H. pylori was detected in 221 (65.6%) of the 337 people by 13C-UBT. The sensitivity, specificity, positive and negative predictive values, and accuracy of the CIM test were 93.2%, 90.5%, 94.9%, 87.5%, and 92.3%, respectively, using 13C-UBT as a gold standard. One month after eradication therapy, the sensitivity, specificity of CIM test were only 50% and 66.7%, 66.7% and 84.6% 3-month after eradication therapy and the sensitivity, specificity increased to 85.7% and 96.9%, respectively, when CIM test was used 6 months after the end of anti- H. pylori therapy. Conclusions: The CIM test is a simple, rapid, accurate, cheap, and near-people test. It may be satisfactory for detecting H. pylori infection in cases without eradication therapy, but it could not differentiate the past or current infection correctly within 6 months after anti- H. pylori therapy. [ABSTRACT FROM AUTHOR]

The hydrated title compound, C8H12O7·H2O, was isolated from the Chinese yam Dioscorea opposita Thunb. An intramolecular OH⋯O hydrogen bond occurs in the organic molecule. In the crystal structure, the molecules are linked by intermolecular OH⋯O hydrogen bonds, thereby forming chains propagating in [010]. [ABSTRACT FROM AUTHOR]

We simulated a shelterwood forest regeneration treatment by reducing basal area, and monitored the response of an avian community in oak-hickory forest on the southern Cumberland Plateau, northern Alabama, USA. We used five treatments: control (no removal), clear-cut (100% removal), and 25, 50, and 75% removal of basal area. Territory mapping was used to quantify bird community between mid-April and July of both 2002 and 2003. Microclimate variables were recorded at each plot. The residual basal area and canopy cover showed three distinct conditions after treatment: closed canopy, open forest, and clear-cut. The microclimate varied among treatments: air temperature was highest in clear-cut plots and lowest in control plots, whereas soil moisture had the opposite pattern. A total of 71 bird species were detected, with 36 of them defending territories. Territory density, species richness, and Shannon diversity index differed among the treatments; the relationship between these bird community indices and the level of basal area removal was quadratic, lowest in the clear-cut plots and highest in the intermediate levels. Although species richness was similar among the control, 25, 50, and 75% removal treatments, species composition varied. The richness difference among treatments became smaller in the second year post-treatment (2003) with an increase in bird density and richness occurring in the clear-cut plots. [ABSTRACT FROM AUTHOR]

Serine:glyoxylate aminotransferase (SGAT) is a key enzyme of photorespiration. Changes in SGAT transcript levels and in enzyme activity following shifts from light to dark or dark to light and after cultivation in media supplemented with 6-benzyladenine (6-BA), a synthetic cytokinin, were analysed in the green alga Chlamydomonas reinhardtii. Cells grown in darkness had higher transcript levels than those grown in the light and transcript levels decreased upon transfer of cultures from dark to light; in contrast, they increased upon shift from light to dark. However, higher enzyme activities were detected in light-grown vs. dark-grown cells, which could be correlated with an elevated photorespiratory activity of the light-grown cultures. Application of the synthetic cytokinin into the medium promoted both the accumulation of SGAT mRNA and enhanced SGAT enzyme activity. Under these conditions an accelerated multiplication of cells as well as higher final cell densities were observed. However, the synthetic cytokinin did not affect chlorophyll content, which is different from cytokinin effects observed in higher plants. The presence of cytokinin-like activities in C. reinhardtii was confirmed using high-performance liquid chromatography. One of these activities was identified by mass-spectroscopy to be zeatin riboside. [ABSTRACT FROM AUTHOR]

1. Nanobiotechnologies have recently attracted significant attention from chemists, biologists, engineers and pharmaceutical scientists. In particular, they have been widely applied to improve drug, protein/peptide and gene delivery. 2. This review presents recent advances in the field of drug, protein/peptide and gene delivery using natural and synthetic polymer nanoparticles and explains how polymeric nanoparticles are specifically designed to suit the needs for targeted delivery of small molecular drugs, proteins/peptides and genes. In addition, some of the challenges and prospects for these technologies are discussed. [ABSTRACT FROM AUTHOR]

The effects of cyhalothrin on the transient outward potassium current in central neurons of Helicoverpa armigera were studied by using the patch clamp techniques. The results showed that before using cyhalothrin (10−5 mmol/L), activation potential was approximately -40 mV, after application of the drug, the activation potential shifted roughly 10 mV to the negative potential direction, so channels can be activated more easily. Before and after cyhalothrin application, the change of current amplitude was insignificant. The value of V1/2 and k of activation curves did not change significantly, however, the V1/2 of the inactivation curves changed significantly. Inactivation curves significantly shifted to a negative direction, so that inactivation of the channels was hastened. It is indicated that there may exit a primary way in which cyhalothrin provides neurotoxicity to the nervous system through the regulation of activation potentials and inactivation state of IA channels. [ABSTRACT FROM AUTHOR]

Myricaria laxiflora is restricted to the riverbanks of the Yangtze River valley and will be completely lost owing to the construction of the Three Gorges Dam. Genetic diversity and structure of nine natural and one ex situ populations were investigated using amplified fragment length polymorphisms (AFLPs). A moderate level of gene diversity was found in natural populations, while the ex situ population had the highest. The F statistics calculated by different approaches consistently revealed a high genetic differentiation among natural populations, contributing >45% of the total gene diversity. The Bayesian-based analysis differentiated nine independent populations in accordance with the sites sampled. Estimates of gene flow by FST and coalescent-based simulation analysis indicated a restricted recurrent gene exchange among populations (Nm = 0.290–0.401), whereas genetic distance-based clustering and coalescent-based assignment analyses revealed significant genetic isolation among populations. The migration pattern in M. laxiflora is best explained by a classical metapopulation model, but with a unique unidirectional direction underlined by hydrochoric force that drove dispersal of seeds and propagules from upstream toward downstream populations. Previous efforts in preserving genomic integrity in ex situ conservation were evaluated, and the results provide valuable information to formulate conservation guidelines for successfully reintroducing M. laxiflora to the wild. [ABSTRACT FROM AUTHOR]

• Distyly is a sexual polymorphism in which plant populations contain two floral morphs differing in morphology and physiology. The dimorphism serves to promote animal-mediated cross-pollination between the floral morphs. Clonal propagation can interfere with the functioning of distyly by compromising intermorph pollinations, resulting in reduced fertility.• Here, we investigate the relations between clonal growth and sexual reproduction in the aquatic macrophyteNymphoides peltata(Menyanthaceae). Surveys of morph representation in 30 populations from five regions of China revealed that most populations exhibited strongly biased morph ratios and 30% contained a single floral morph.• Experimental pollinations indicate thatN. peltatapossesses a strong dimorphic incompatibility system preventing self and intramorph fertilizations. An experiment involving the manipulation of morph ratios in an experimental population and an investigation in a natural population with strong morph substructure both provided evidence that compatible pollen dilution limits fertility.• Despite constraints on the functioning of distyly inN. peltatawe found no evidence for evolutionary changes to the heterostylous syndrome, as reported inNymphoides, including populations ofN. peltatain other parts of its geographical range.New Phytologist(2004)doi: 10.1111/j.1469-8137.2004.01234.x© New Phytologist(2004) [ABSTRACT FROM AUTHOR]

This article studies currency substitution in a model where domestic money suffers from lack of confidence. When agents' confidence is exogenous and constant, there is a unique but unstable dual-money steady state. However, when agents' confidence is updated endogenously, the dynamics of currency substitution are driven by agents' evolving beliefs, and the economy always con verges to an equilibrium where both monies circulate. Therefore, the economy under endogenous beliefs exhibits both persistence in currency substitution and tenacity of domestic money. Furthermore, in general, there are multiple steady states, which can be Pareto ranked by the degree of currency substitution. [ABSTRACT FROM AUTHOR]

A dynamic model for geared multi-body system containing gear, bar and shaft is proposed and a new gear element is particularly developed based on a specific finite element theory. The gear element can take into account time-variant meshing stiffness, the gear errors, and the couplings between the torsional and the lateral vibrations of gears. The accuracy and reliability of the gear element are confirmed by comparing the simulated with the experimental results of rotational vibration accelerations. A gear–bar mechanism composing one sun gear, one planetary gear and two bars is simulated dynamically. The influences of non-uniform gear speed, time-variant meshing stiffness and bar stiffness on the dynamic behaviours are investigated. Copyright © 2002 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The complex permittivity of a number of liquid dielectrics has been measured with the use of the in-waveguide technique at the X and Ku band. The TRL calibration procedure is applied for the calibration of the waveguide system. The measured results of permittivity of distilled water agree well with those published in the literature. The measured permittivity for other liquids such as ethyl alcohol, propyl alcohol, benzene, chlorobenzene, menthanol, and cyclothexane are also shown, and the properties of these liquids are discussed. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 240–243, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10427 [ABSTRACT FROM AUTHOR]

A surface-based integral-equation formulation for coupled electromagnetic and circuit simulation is presented. The approach is sufficiently general to model arbitrarily shaped structures and high-frequency skin effects. The formulation is implemented in both an equivalent circuit form for spice compatibility, and in a more general form as a coupled-matrix system outside spice. The overall approach can be interpreted as either a modified surface-only partial element equivalent circuit approach, or as a circuit-coupled version of the surface-based method of moments. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 103–106, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10386 [ABSTRACT FROM AUTHOR]

Retroviral integrase, an essential enzyme for replication of human immunodeficiency virus type-1 (HIV-1) and other retroviruses, contains three structurally distinct domains, an N-terminal domain, the catalytic core and a C-terminal domain. To elucidate their spatial arrangement, we have solved the structure of a fragment of HIV-1 integrase comprising the N-terminal and catalytic core domains. This structure reveals a dimer interface between the N-terminal domains different from that observed for the isolated domain. It also complements the previously determined structure of the C-terminal two domains of HIV-1 integrase; superposition of the conserved catalytic core of the two structures results in a plausible full-length integrase dimer. Furthermore, an integrase tetramer formed by crystal lattice contacts bears structural resemblance to a related bacterial transposase, Tn5, and exhibits positively charged channels suitable for DNA binding. [ABSTRACT FROM AUTHOR]

Nitrogen (N) is an essential nutrient for plant growth, and most plants absorb it as nitrate. AtNRG2 has been reported to play an important role in nitrate regulation. In this study, we investigated the functions of AtNRG2 family members of Arabidopsis thaliana and maize in nitrate signalling and metabolism. Our results showed that both AtNRG2.10 and AtNRG2.15 regulated nitrate signalling and metabolism. Overexpression of AtNRG2.11 (AtNRG2) could promote plant growth and improve nitrogen use efficiency (NUE). In addition, the maize genome harbors 23 ZmNRG2 members. We detected the expression of these genes treated with nitrate and the expression of four genes was strongly induced with ZmNRG2.7 having the highest levels. Overexpression of ZmNRG2.7 in the atnrg2 mutant could restore the defects of atnrg2, suggesting that ZmNRG2.7 is involved in nitrate signalling and metabolism. Moreover, the overexpression lines of ZmNRG2.7 showed increased biomass and NUE. These findings demonstrate that at least a part of NRG2 family genes in Arabidopsis and maize regulate nitrate signalling and provide a molecular basis for improving the NUE of crops. [ABSTRACT FROM AUTHOR]

Six polymorphic microsatellite markers were isolated and characterized using an enriched library technique in the large yellow croaker (Pseudosciaena crocea Richardson, 1864), a commercially important marine fish in China. They showed PIC (polymorphism information content) ranging from 0.064 to 0.885 (average of 0.580) and allele numbers ranging from two to 13 (average of 7.5), which were useful for the studies on population genetics and selective breeding of the large yellow croaker. [ABSTRACT FROM AUTHOR]

The title compound, [Co(C12H8N2)(H2O)4]2(C10H2O8), consists of discrete tetra­aqua­(1,10-phenanthroline)cobalt(II) cations and 1,2,4,5-benzene­tetra­carboxyl­ate anions. The CoII atom is octa­hedrally coordinated by two N atoms of the 1,10-phenanthroline ligand and four O atoms of water mol­ecules. The anion lies on an inversion centre. A two-dimensional hydrogen-bonding network is formed by O atoms of benzene­tetra­carboxyl­ate and the coordinated water mol­ecules. [ABSTRACT FROM AUTHOR]

The finite-element method (FEM) is applied to analyze a thin substrate antenna with shorting posts. The resonant frequency of this kind of antenna is studied and compared with other numerical result and experimental data. [ABSTRACT FROM AUTHOR]

Dyadic Green's functions for a dielectric half-space, based on “Formulation C,” are computed by a fast algorithm using the discrete complex image method with a two-level approximation. The results show very good agreement with those calculated by direct numerical integration. It is expected to be used for the analysis of radiation and scattering from targets buried underground. © 2000 John Wiley & Sons, Inc. Microwave Opt Technol Lett 25: 287–289, 2000. [ABSTRACT FROM AUTHOR]

Hepatoblastoma, a common extracranial malignant solid tumor in childhood, is often detected at an advanced stage and is difficult to treat surgically. Despite the availability of multiple comprehensive treatments that can be combined with surgery, hepatoblastoma treatment outcomes remain poor. Surgery is the main treatment strategy for hepatoblastoma, but it faces many challenges, including tumor attachment to surrounding tissues, tumor wrapping or invading of vital organs and tissues, the presence of giant or multiple tumors, distant metastasis, the formation of a tumor thrombus, and significant surgical trauma. In this review, we discuss recent research advances and propose potential strategies for overcoming these challenges. Such strategies may improve the rate of hepatoblastoma resection and local control in children, as well as reduce complications and trauma. [ABSTRACT FROM AUTHOR]

A 3‐layered composite plate is innovatively fabricated via composite rolling of 1.6 wt% B stainless steel surrounded by two layers of boron‐free steels. The tensile properties of composite and non‐composite plates are comparatively tested and analyzed. Besides, the microstructure evolution of the investigated plates is characterized in detail. It is found that the composite specimens exhibit higher tensile elongation comparing with that of non‐composite specimens. Specifically, the engineering strain of the 1050 °C × 30 min solution‐treated specimens reaches to 12.5 ± 0.8% which is 2.5–3.0 times as high as that of non‐composite specimens. In addition, the as‐cast lamellar borides break into bar‐shaped structures in hot rolled plates, however, their morphology and distribution hardly change after solution treatment. Besides, the transition regions between the core and clad layers are formed and characterized by medium‐sized recrystallized grains and fine borides in the solution‐treated composite specimens. The enhancement mechanism of tensile elongation is mainly analyzed in term of the geometrical restriction of necking in the composite plate during tensile deformation. This paper provides a promising method to effectively enhance the tensile fracture elongation for these metallic materials with poor plasticity like high borated stainless steels. [ABSTRACT FROM AUTHOR]

A novel synthetic protocol for the direct oxidation of alkanes, including cyclic and linear ones, to give ketones and alcohols using hydrogen peroxide as terminal oxidant under ambient conditions is presented. The active catalyst for this challenging transformation is conveniently generated by combination of simple Fe salts with N‐methyl bis(picolylamine) (Me‐bpa). Utilizing picolinic acid as additive leads to improved yields of ketones and alcohols (32‐57 %). The reaction can be conveniently scaled up to multi‐g scale. [ABSTRACT FROM AUTHOR]

The novel protein elicitor GP1pro is the protein component of glycoprotein GP‐1 isolated and identified from Streptomyces kanasensis ZX01. GP1pro induces the production of reactive oxygen species (ROS) and a hypersensitive response (HR), along with the accumulation of resistance‐related genes and secondary metabolites. It ultimately regulates plant defence responses. Further analysis revealed that GP1pro interacts with the PIP2‐family aquaporin protein NbPIP2;4 on the plant plasma membrane (PM) in Nicotiana benthamiana. PM localization is necessary for inducing GP1pro resistance. These results demonstrate that NbPIP2;4 acts as a H2O2 transporter to positively regulate plant immunity and ROS accumulation. In summary, this study elucidates a conserved and novel pathway caused by GP1pro to initiate host cellular defences by targeting the plant aquaporin protein NbPIP2;4 and transporting apoplast‐to‐cytoplast H2O2 to regulate plant immunity. Summary Statement: We found a protein elicitor from actinomycetes that interacts with the tobacco aquaporin NbPIP2;4 to regulate plant immunity and enhance tobacco disease resistance. This provides a basis for the development of protein elicitors for green plant protection strategies. [ABSTRACT FROM AUTHOR]

Breast cancer is the most common malignant tumor and the leading cause of cancer-related deaths in women worldwide. Effective means of predicting the prognosis of breast cancer are very helpful in guiding treatment and improving patients' survival. Features extracted by radiomics reflect the genetic and molecular characteristics of a tumor and are related to its biological behavior and the patient's prognosis. Thus, radiomics provides a new approach to noninvasive assessment of breast cancer prognosis. Ultrasound is one of the commonest clinical means of examining breast cancer. In recent years, some results of research into ultrasound radiomics for diagnosing breast cancer, predicting lymph node status, treatment response, recurrence and survival times, and other aspects, have been published. In this article, we review the current research status and technical challenges of ultrasound radiomics for predicting breast cancer prognosis. We aim to provide a reference for radiomics researchers, promote the development of ultrasound radiomics, and advance its clinical application. [ABSTRACT FROM AUTHOR]

This Letter proposes an extended disturbance observer (EDO) based adaptive robust control method for motion control of DC motors. An adaptive part for structured uncertainties, an EDO for unstructured uncertainties and a feedback robust law for global robustness are designed in this method. The theoretical analysis guarantees a prescribed tracking performance under various uncertainties and comparative numerical simulation shows the excellent high-precision performance of proposed method on DC motor motion control. [ABSTRACT FROM AUTHOR]

The article discusses the geodynamic setting and metallogenesis of the Early Paleozoic orogenic gold deposits in the North Altyn. Topics include formation of the orogenic gold deposits during compressional to transpressional deformation process, hydrothermal alteration including pyritization, silification, and seritization, and the association between orogenic ores formation and the peak period of continental accretion rate.

A case study of 6-year-old girl is presented who was hospitalized for a persistent cough for 1 month and haemoptysis for 2 days. Topics include examines before admission, the patient presented with 40 ml of haemoptysis, four times per day and the medical history and physical examination findings of the patient were unremarkable.

In this study, a novel two-step model predictive control (MPC) for Hammerstein systems subject to norm-bounded disturbance is addressed. In the first step, the intermediate control law for the linear part of the system is posed as the solution to the unconstrained MPC problem that minimises a quadratic cost function over a given finite time, for which the solution is determined by a novel Riccati iterative equation. In the second step, the actual control move is obtained by solving non-linear algebraic equation group and desaturation. The quadratic boundedness technique is used to specify the stability for closed-loop system with norm-bounded disturbance, and the sufficient conditions for quadratic convergent of the system state are presented. Simulation results demonstrate the effectiveness of the proposed approach to this class of systems. [ABSTRACT FROM AUTHOR]

Kernelised correlation filter (KCF)-based trackers have recently attracted considerable attention due to their exciting accuracy and efficiency. Numerous improvements have been made later for coping with scales variation or partial occlusion etc. However, when there is an abrupt motion between the consecutive image frames, these trackers would face failure. To alleviate the problem, the authors present an extended cuckoo search (CS)-based KCF tracker (called ECSKCF). At first, the extended CS algorithm is constructed by the Simplex method (SM). CS has obvious capability in global search while the SM has exceptional advantage in local search. Based on ECS method, motion prediction is transformed to globally search for optimal position intending to enhance the quality of base image. Then, combined ECS with Gaussian distribution, a hybrid motion model is introduced to KCF framework, which has the capability of capturing abrupt motion. Finally, a unified framework is designed to track smooth or abrupt motion simultaneously. Extensive experimental results in both quantitative and qualitative measures demonstrate the effectiveness of the authors' proposed method for abrupt motion tracking. [ABSTRACT FROM AUTHOR]

A robust method to detect foreground regions in video sequences is presented. For each pixel, the time series of pixel intensity is represented as symbol sequences that are trained and modelled using the Markov model to obtain the anomaly detection threshold. The foreground extraction is performed by comparing the anomaly transition probability of each pixel and its detection threshold. The experimental results demonstrate that the proposed method outperforms the traditional methods. [ABSTRACT FROM AUTHOR]

The article discusses the intermolecular structure of Bis(4-nitrobenzoato)bis(trimethylsilylmethyl)tin(IV). The geometry at the six-coordinate Sn atom is distorted octahedral with an approximately planar equatorial belt made up of the four O atoms of two carboxylate groups and the axial positions occupied by two trimethylsilylmethyl groups. The biological activity of diorganotin compounds depends mainly on the alkyl groups and the ligands The structure of the compound is analogous to that of bis(4 -methoxylbenzo ato)phenyl- (trimethylsilylmethyl)tin(IV). The carboxylate groups act as asymmetric chelating groups.

Experimental results of the complex permittivity and permeability of carbonyl iron powders are presented. It is found that the complex permeability of these samples is quite similar due to the high content of iron while the complex permittivity of the samples is significantly different for various contents of the samples. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 458–459, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20335 [ABSTRACT FROM AUTHOR]

A corrugated horn antenna is modeled using the three-dimensional FDTD method. The computed E-plane radiation pattern shows a good agreement with those measured and calculated using the MoM published in the literature. The H-plane radiation pattern and the cross-polarization patterns for both E- and H-plane are also obtained since the corrugated horn is calculated by a three dimensional model. The radiation characteristics for various frequencies have also been analyzed. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 83–84, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10379 [ABSTRACT FROM AUTHOR]