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Considering that the current low-stress cropping method for large-diameter metal bar has the disadvantages of large cutting force and drastic change of loading force, a new low-stress cropping method is proposed based on the co-induced crack initiation by rotating-bending and slotting. Based on the strength theory and fatigue damage theory, the dynamic bending cutting model is established, proving that the prestressed bending action reduces the slotted cutting and cracking forces. The formula of main cutting force during slotting considering rotation speed under the prestressed action is obtained by establishing simulation model combined with the experimental platform of the prestressed rotating-bending cutting and cracking process. Three types of initiation crack are proposed, and the reasonable process parameters for effective connection of slotting and ideal crack initiation type are obtained. The experimental results of 45 steel bar show that the cutting force is reduced to only 75.79% of the traditional cutting slotting, and the crack initiation force is reduced to only 1.88% of the traditional shearing force. Similarly, the test results of Q235 steel, 6061 aluminum alloy, and 304 austenitic stainless steel also show that the cutting force of prestressed slotting is reduced and the slotting and cracking connection can be realized, which can meet the requirements of low-stress slotting and cracking of the bar with large diameter. Investigation of co-induced crack initiation process by prestressed slotting and rotating-bending in low-stress cropping [ABSTRACT FROM AUTHOR]

Faults in train mechanical parts pose a significant safety hazard to railway transportation. Although some image detection methods have replaced manual fault detection of train mechanical parts, the detection effect on small mechanical parts under low illumination conditions is not ideal. To improve the accuracy and efficiency of the detection of train faults under different environments, we propose a multi-mode aggregation feature enhanced network (MAFENet) based on a single-stage detector (SSD). This network uses the idea of a two-step adjustment structure from coarse to fine and uses the K-means algorithm to design anchors. The receptive field enhancement module (RFEM) is designed to obtain the fusion features of different receptive fields. The attention-guided detail feature enhancement module (ADEM) is designed to complement the detailed features of deep-level feature maps. Meanwhile, the complete intersection over union (CIoU) loss is used to obtain more accurate bounding boxes. The experimental results on the train mechanical parts fault (TMPF) dataset showed that the detection performance of MAFENet is better than those of other SSD models. MAFENet with an input size of 320 × 320 pixels can achieve a mean average precision (mAP) of 0.9787 and a detection speed of 33 frames per second (FPS), which indicates that it can realize real-time detection, has good robustness to images under different environmental conditions, and can be used to improve the efficiency of the detection of faulty train parts. [ABSTRACT FROM AUTHOR]

Plasma membrane Ca2+-ATPases (PMCAs) are key regulators of global Ca2+ homeostasis and local intracellular Ca2+ dynamics. Recently, Neuroplastin (NPTN) and basigin were identified as previously unrecognized obligatory subunits of PMCAs that dramatically increase the efficiency of PMCA-mediated Ca2+ clearance. Here, we report the cryo-EM structure of human PMCA1 (hPMCA1) in complex with NPTN at a resolution of 4.1 Å for the overall structure and 3.9 Å for the transmembrane domain. The single transmembrane helix of NPTN interacts with the TM8-9-linker and TM10 of hPMCA1. The subunits are required for the hPMCA1 functional activity. The NPTN-bound hPMCA1 closely resembles the E1-Mg2+ structure of endo(sarco)plasmic reticulum Ca2+ ATPase and the Ca2+ site is exposed through a large open cytoplasmic pathway. This structure provides insight into how the subunits bind to the PMCAs and serves as an important basis for understanding the functional mechanisms of this essential calcium pump family. [ABSTRACT FROM AUTHOR]

PKD2L1, also termed TRPP3 from the TRPP subfamily (polycystic TRP channels), is involved in the sour sensation and other pH-dependent processes. PKD2L1 is believed to be a non-selective cation channel that can be regulated by voltage, protons, and calcium. Despite its considerable importance, the molecular mechanisms underlying PKD2L1 regulations are largely unknown. Here, we determine the PKD2L1 atomic structure at 3.38 Å resolution by cryo-electron microscopy, whereby side chains of nearly all residues are assigned. Unlike its ortholog PKD2, the pore helix (PH) and transmembrane segment 6 (S6) of PKD2L1, which are involved in upper and lower-gate opening, adopt an open conformation. Structural comparisons of PKD2L1 with a PKD2-based homologous model indicate that the pore domain dilation is coupled to conformational changes of voltage-sensing domains (VSDs) via a series of π–π interactions, suggesting a potential PKD2L1 gating mechanism. [ABSTRACT FROM AUTHOR]

Fault diagnosis is critical in PHM (Prognostics and Health Management) of machine tools due to its great significance in such efforts as prolonging lifespan, improving production efficiency, and reducing production costs. For machine tool manufacturers, a general fault diagnosis method and a software framework are needed to construct fault diagnosis systems for various machine tools and fault types, or the same type of machine tools under various life cycles, working conditions, and operating environments. A configurable method for fault diagnosis knowledge of machine tools (CMFDK-MT) is thus proposed in this paper. Firstly, an ontology-based fault diagnosis method for machine tools and an improved process of fault diagnosis with knowledge bases are introduced. Based on these, a framework of a knowledge-based configurable fault diagnosis platform for machine tools (KCFDP-MT) is designed. KCFDP-MT supports explicit knowledge representation with formal semantics, efficient knowledge utilization, and efficient integration of various fault diagnosis methods and technologies. Then, the configuration approaches for fault diagnosis activities, namely fault detection, identification, diagnosis, and solving, are studied respectively. The configuration and implementation methods of the KCFDP-MT framework are also presented. Finally, a prototype system is constructed for a CNC hobbing machine tool. Two cases of rolling bearing and gear based on signal processing are carried out to verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

The intersection workspace of multi-finger hands means the overlapping workspace in 3D Euclidean space where several fingertips can reach together, and is very valuable for grasp space planning, motion control and mechanical design for multi-finger hands. But, the intersection workspaces usually have sophisticated forms, which are really hard for robotic experts to image them. We present a general approach to visualize and analyze the intersection workspace of multi-finger hands. We firstly deduce the displacement equation of the fingertip, then generate 3D workspace of the fingertip and lastly obtain the intersection workspace of the multi-finger hands. This approach can visualize intersection workspaces with integrated forms and contours, and analyze the volume of the intersection workspaces. The vivid form and volume analysis of intersection workspaces are useful for robotic experts to accurately and intuitionally understand the fingertip motion ranges, plan the motion routes of fingers and avoid the motion collision among fingers. [ABSTRACT FROM AUTHOR]

The oncogenic mechanisms of overnutrition, a confirmed independent cancer risk factor, remain poorly understood. Herein, we report that enoyl-CoA hydratase-1 (ECHS1), the enzyme involved in the oxidation of fatty acids (FAs) and branched-chain amino acids (BCAAs), senses nutrients and promotes mTOR activation and apoptotic resistance. Nutrients-promoted acetylation of lys101 of ECHS1 impedes ECHS1 activity by impairing enoyl-CoA binding, promoting ECHS1 degradation and blocking its mitochondrial translocation through inducing ubiquitination. As a result, nutrients induce the accumulation of BCAAs and FAs that activate mTOR signaling and stimulate apoptosis, respectively. The latter was overcome by selection of BCL-2 overexpressing cells under overnutrition conditions. The oncogenic effects of nutrients were reversed by SIRT3, which deacetylates lys101 acetylation. Severely decreased ECHS1, accumulation of BCAAs and FAs, activation of mTOR and overexpression of BCL-2 were observed in cancer tissues from metabolic organs. Our results identified ECHS1, a nutrients-sensing protein that transforms nutrient signals into oncogenic signals. [ABSTRACT FROM AUTHOR]

Purpose: We aimed to determine cut-offs between mild, moderate and severe myelopathy on the modified Japanese Orthopedic Association (mJOA) score.Methods: Between December 2005 and January 2011, 757 patients with clinically diagnosed DCM were enrolled in the prospective AOSpine North America (n = 278) or International (n = 479) study at 26 sites. Functional status and quality of life were evaluated at baseline using a variety of outcome measures. Using the Nurick score as an anchor, receiver operating curve (ROC) analysis was conducted to determine cut-offs between mild, moderate and severe disease. The validity of the identified cut-offs was evaluated by examining whether patients in different severity groups differed in terms of impairment, disability, quality of life and number of signs and symptoms.Results: A mJOA of 14 was determined to be the cut-off between mild and moderate myelopathy and a mJOA of 11 was the cut-off score between moderate and severe disease. Patients in the severe myelopathy group (n = 254) had significantly reduced quality of life and functional status and a greater number of signs and symptoms compared to patients classified as mild (n = 190) or moderate (n = 296).Conclusions: Mild myelopathy can be defined as mJOA from 15 to 17, moderate as mJOA from 12 to 14 and severe as mJOA from 0 to 11. These categories should be adopted worldwide to standardize clinical assessment of DCM. [ABSTRACT FROM AUTHOR]

Landscape index had a relationship with the ecological risk of land-use, as one of the important indicators to measure the ecological risk of land-use. The traditional ecological risk assessment of land-use did not consider the influence of the particle scale on landscape indices of landscape. In order to improve the science of ecological risk assessment for land-use, and to provide a scientific basis for land-use management decisions, in this paper, the National Nature Reserve of Shengjin Lake in Anhui province was chosen, the remote sensing TM images from 1986, 2002, to 2011 were selected, and GIS technology and measures were used to analyze, besides, Fragstats software was selected to get a different scale of landscape indices. The assessment model for land-use ecological risk was established, and land-use ecological risk in 2015 and which was predicted through multiple linear regression and principal component analysis in 2020. The results showed that the evaluation for land-use ecological risk was influenced by landscape scale. The land-use ecological risk in the study area had increased-decreased-increased. It was predicted that the land-use ecological risk in the study area would reach 2.32 in 2015 and 2.72 in 2020. Ecological risk was gradually gathering at the National Nature Reserve of Shengjin Lake in Anhui province. [ABSTRACT FROM AUTHOR]

The structural, electronic, dielectric and optical properties of tetragonal LaSrAlO4 are studied in detail using density functional theory calculations. The energy band structures and density of states are predicted by generalized gradient approximation (GGA) and local density approximation (LDA) respectively. The fundamental band gaps of LaSrAlO4 are all indirect by GGA (2.860 eV) and LDA (2.863 eV) calculations. The complex dielectric function was calculated. There are two peaks in the real part ε1(ω) and three peaks in the imaginary part ε2(ω). The optical spectra are assigned to the interband transition from O valence to La and Sr conduction bands in the low energy region. In addition, the electron energy-loss spectrum, optical conductivity, reflectivity spectrum, and refractive index, are given to support the potential applications formicrowave dielectric ceramics. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is among the most aggressive primary brain tumors, with a median survival rate of 12-15 months. MicroRNAs have been implicated in GBM development as oncogenes or tumor suppressors. In this study, we demonstrated that miR-519a expression was frequently downregulated in GBM specimens and cell lines, and that low-levels miR-519a expression significantly correlated with poor outcomes associated with GBM. Analysis of The Cancer Genome Atlas also demonstrated that low miR-519a expression can predict poor clinical outcomes in classical and proneural GBM subtypes. Functionally, re-expression of miR-519a effectively reduced GBM cell proliferation, migration, and invasion. Mechanistically, we confirmed that the signal transducer and activator of transcription 3 (STAT3) 3′-UTR was a putative target of miR-519a, and that re-expression of STAT3 abrogated miR-519a function in GBM cells. Furthermore, we found that STAT3 expression negatively correlated with that of miR-519a in human GBM tissues. These results elucidated the prognostic value and tumor-suppressor role of miR-519a in GBM and further suggested it as a potential therapeutic target for GBM treatment. [ABSTRACT FROM AUTHOR]

Background: Various anterior lumbar surgical approaches, including the minimally invasive approach, have greatly improved in recent years. Vascular complications resulting from ALIF are frequently reported. Little information is available about the safety of large blood vessel stretch. We evaluated the right side stretch limit (RSSL) of the abdominal aorta (AAA) and the inferior vena cava (IVC) without blood flow occlusion and investigated stretch‑induced histological injury and thrombosis in the iliac and femoral arteries and veins and the stretched vessels. Materials and Methods: The RSSL of blood vessels in five adult goats was measured by counting the number of 0.5‑cm‑thick wood slabs that were inserted between the right lumbar edge and the stretch hook. Twenty seven adult goats were divided into three groups to investigate histological injury and thrombosis under a stretch to 0.5 cm (group I) 1.5 cm (group II) for 2 h, or no stretch (group III). Blood vessel samples from groups I and II were analyzed on postsurgical days 1, 3, and 7. Thrombogenesis was examined in the iliac and femoral arteries and veins. Results: The RSSL of large blood vessels in front of L4/5 was 1.5 cm from the right lumbar edge. All goats survived surgery without complications. No injury or thrombosis in the large blood vessels in front of the lumbar vertebrae and in the iliac or femoral arteries and veins was observed. Under light microscopy, group I showed slight swelling of endothelial cells in the AAA and no histological injury of the IVC. The AAA of group II showed endothelial cell damage, unclear organelles, and incomplete cell connections by electron microscopy. Conclusions: The AAA and IVC in a goat model can be stretched by ≤0.5 cm, with no thrombosis in the AAA, IVC, iliac or femoral arteries and veins. [ABSTRACT FROM AUTHOR]

Background: Isoascorbic acid is a stereoisomer of L-ascorbic acid, and widely used as a food antioxidant. However, its highly hydrophilic behavior prevents its application in cosmetics or fats and oils-based foods. To overcome this problem, D-isoascorbyl palmitate was synthesized in the present study for improving the isoascorbic acid's oil solubility with an immobilized lipase in organic media. The structural information of synthesized product was clarified using LC-ESI-MS, FT-IR, 1H and 13C NMR analysis, and process parameters for high yield of D-isoascorbyl palmitate were optimized by using One-factor-at-a-time experiments and response surface methodology (RSM). Results: The synthesized product had the purity of 95% and its structural characteristics were confirmed as isoascorbyl palmitate by LC-ESI-MS, FT-IR, 1H, and 13C NMR analysis. Results from "one-factor-at-a-time" experiments indicated that the enzyme load, reaction temperature and D-isoascorbic-to-palmitic acid molar ratio had a significant effect on the D-isoascorbyl palmitate conversion rate. 95.32% of conversion rate was obtained by using response surface methodology (RSM) under the the optimized condition: enzyme load of 20% (w/w), reaction temperature of 53°C and D- isoascorbic-to-palmitic acid molar ratio of 1:4 when the reaction parameters were set as: acetone 20 mL, 40 g/L of molecular sieves content, 200 rpm speed for 24-h reaction time. Conclusion: The findings of this study can become a reference for developing industrial processes for the preparation of isoascorbic acid ester, which might be used in food additives, cosmetic formulations and for the synthesis of other isoascorbic acid derivatives. [ABSTRACT FROM AUTHOR]

Background D-isoascorbic acid is a food antioxidant additive and used in accordance with Good Manufacturing Practice (GMP). High solubility in water (about 150 g/L at 25°C) reduces its effectiveness in stabilizing fats and oils. Our research group had successfully synthesized Disoascorbyl palmitate using immobilized lipase Novozym 435 as a biocatalyst. Low production efficiency of D-isoascorbyl palmitate is still a problem for industrial production due to the long reaction time of over 24 h. In the present work, ultrasonic treatment was applied for accelerating the reaction process. The operation parameters were optimized to obtain the maximum D-isoascorbyl palmitate conversion rate by using a 5-level-4-factor Central Composite Design (CCD) and Response Surface Methdology (RSM). The reaction apparent kinetic parameters under the ultrasound treatment and mechanical shaking conditions were also determined and compared. Results Results showed that ultrasound treatment decreased the reaction time by over 50%. Disoascorbyl palmitate yielded to 94.32 ± 0.17% and the productivity reached to 8.67 g L-1 h-1 under the optimized conditions as: 9% of enzyme load (w/w), 61°C of reaction temperature, 1:5 of D- isoascorbic-to-palmitic acid molar ratio, and 137 W of the ultrasound power. The immobilized lipase Novozym 435 could be reused for 7 times with 65% of the remained Disoascorbyl palmitate conversion rate. The reaction kinetics showed that the maximum apparent reaction rate ( max v ) of the ultrasound-assisted reaction was 2.85 times higher than that of the mechanical shaking, which proved that ultrasound treatment significantly enhanced the reaction efficiency. Conclusion A systematic study on ultrasound-assisted enzymatic esterification for D-isoascorbyl palmitate production is reported. The results show a promising perspective of the ultrasound technique to reduce the reaction time and improve the production efficiency. The commercial D-isoascorbyl palmitate synthesis will be potentially realized due to this ultrasound-promoted esters synthesis method. [ABSTRACT FROM AUTHOR]

Carvedilol is one of the most effective beta blockers for preventing ventricular tachyarrhythmias in heart failure, but the mechanisms underlying its favorable antiarrhythmic benefits remain unclear. Spontaneous Ca2+ waves, also called store overload-induced Ca2+ release (SOICR), evoke ventricular tachyarrhythmias in individuals with heart failure. Here we show that carvedilol is the only beta blocker tested that effectively suppresses SOICR by directly reducing the open duration of the cardiac ryanodine receptor (RyR2). This unique anti-SOICR activity of carvedilol, combined with its beta-blocking activity, probably contributes to its favorable antiarrhythmic effect. To enable optimal titration of carvedilol's actions as a beta blocker and as a suppressor of SOICR separately, we developed a new SOICR-inhibiting, minimally beta-blocking carvedilol analog, VK-II-86. VK-II-86 prevented stress-induced ventricular tachyarrhythmias in RyR2-mutant mice and did so more effectively when combined with either of the selective beta blockers metoprolol or bisoprolol. Combining SOICR inhibition with optimal beta blockade has the potential to provide antiarrhythmic therapy that can be tailored to individual patients. [ABSTRACT FROM AUTHOR]

Tidal flow and fine-sediment transport at the South Channel-North Passage of the partially-mixed Changjiang River estuary were studied using a two-dimensional horizontal (2DH) numerical model. This 2DH model was achieved by depth-integrating the momentum and convection-diffusion equations. The Alternating Direction Implicit scheme was used to solve the governing equations. The iterative method was adopted for the calculation of convection and diffusion terms of momentum equation. Comparisons between calculated and measured results (tidal elevations and depth-averaged velocities) have shown reasonable agreement. Horizontal distributions of tidal current velocity and suspended sediment concentration were qualitatively consistent with observations. Those modeled results were analyzed to elucidate the mechanisms for the formation of the turbidity maximum and intratidal variations in fine-sediment transport processes. [ABSTRACT FROM AUTHOR]

This paper proposes a multilevel placer targeted at hierarchical FPGA (Field Programmable Gate Array) devices. The placer is based on multilevel optimization method which combines the multilevel bottom-up clustering process and top-down placement process into a V-cycle. It provides superior wirelength results over a known heuristic high-quality placement tool on a set of large circuits, when restricted to a short run time. For example, it can generate a placement result for a circuit with 5000 4-LUTs (4-Input Look Up Tables) in 70 seconds, almost 30% decrease of wirelength compared with than the heuristic implementation that takes over 500 seconds. We have verified our algorithm yields good quality-time tradeoff results as a low-temperature simulated annealing refinement process can only improve the result by an average of 1.11% at the cost of over 25-fold runtime. [ABSTRACT FROM AUTHOR]

Lgr5 is a member of the G protein receptor super-family and was shown recently to be a stem cell marker for cells with intestinal differentiation. Its over-expression has been demonstrated in hepatocellular, basal cell carcinoma, and ovarian cancers but the underlying mechanisms are poorly understood. The aim of this study was to investigate if Lgr5 over-expression was correlated with human colorectal carcinogenesis and its potential correlation with β-catenin. The study was carried out on a tissue microarray that consisted of 102 colorectal carcinomas (CRC; M:F = 55:47), 18 colon adenoma, and 12 colon normal mucosa cases. Immunostains were performed with the standard EnVision method with primary antibodies against Lgr5, β-catenin, and p53 antigens. Immunoreactivity of neoplastic cells to each antibody was double-blindly semi-quantified by two pathologists and the data were analyzed with the Chi-square and Spearman rank correlation tests. Subsequently, expression of Lgr5 in tissue sections of tumor centre and invasive margins of 21 cases of CRC certified to be immunoreactive of Lgr5 in TMA were evaluated and possible differences of Lgr5 expression between them were analyzed. Lgr5 immunoreactivity was observed only in single cells in the base of normal colon mucosal crypts but high in 28% (five out of 18) adenomas, and significantly higher in 54% (55/102, p = 0.016) CRC cases. In normal mucosa, adenoma, and CRC, β-catenin expression was seen in 25% (three out of 12), 27% (five out of 18), and 81% (83/102) cases, respectively, in contrast to 0, 0, and 40% (41/102) for p53 expression, respectively. In CRC, Lgr5 expression was more intense in women than men ( p < 0.0001), and positively correlated with β-catenin expression ( p < 0.001), but not with patients’ ages, tumor sizes, nodal status, TNM stages, and p53 expression. Different expression of Lgr5 between tumor centre and invasive margins was not found ( p > 0.05). The results suggest that up-regulation of Lgr5 expression, especially in female patients, may play an important role in colorectal carcinogenesis, probably through the WNT/β-catenin pathway, but not involve the progression of the CRC. [ABSTRACT FROM AUTHOR]

Impaired local cellular immunity is one of the mechanisms responsible for condyloma acuminatum (CA) recurrence. The activation of dendritic cells (DCs) is important in vaccine development. We investigated the effect of different toll like receptor (TLR) agonists including LPS (TLR4 agonist), polyinosinic acid-polycytidylic acid (PIC, TLR3 agonist), CpG oligonucleotide (TLR9 agonist), and imiquimod (TLR7 agonist) on human monocyte-derived dendritic cells (mdDCs) loading of human papillomavirus (HPV) type 11 E7 epitope. As a result, we found that mdDCs loading HLA-A*0201-restricted HPV 11 E7 CTL epitope peptide could respond to the TLR agonists, especially LPS and PIC. This was characterized by an enhanced expression of CD40, CD80, CD86, CD83 and HLA-DR, and a high level of IL-12 production. TLR agonists, especially PIC, enhanced the ability of E7-loaded mdDCs to induce IFN-γ-secretion CD4+ naïve T cells. Moreover, E7-loaded mdDCs exposed to TLR agonists augmented autologous T cell responses including effector cytokines production and specific cytotoxic T lymphocyte (CTL) responses. In addition, the inhibitory effect of IL-10 on mdDCs maturation could be partially restored by LPS, PIC or imiquimod. Taken together, these results demonstrate that TLR agonists promoted the maturation of E7-loaded mdDCs and their ability to induce T help type 1 polarization and augment E7-specific T cell responses. These data also indicated that TLR3/4 agonists might be effective adjuvants of mdDC-based vaccines against CA. [ABSTRACT FROM AUTHOR]

The chaotic dynamics of the transport equation for the L-mode to H-mode near the plasma in a tokamak is studied in detail with the Melnikov method. The transport equations represent a system with external and parametric excitation. The critical curves separating the chaotic regions and nonchaotic regions are presented for the system with periodically external excitation and linear parametric excitation, or cubic parametric excitation, respectively. The results obtained here show that there exist uncontrollable regions in which chaos always take place via heteroclinic bifurcation for the system with linear or cubic parametric excitation. Especially, there exists a controllable frequency, excited at which chaos does not occur via homoclinic bifurcation no matter how large the excitation amplitude is for the system with cubic parametric excitation. Some complicated dynamical behaviors are obtained for this class of systems. [ABSTRACT FROM AUTHOR]

Nickel accumulated in midugt of Spodoptera litura Fabricius could induce the express on of metallothionein, one of the most important detoxification proteins in organisms. In the present study, the effects of dietary nickel on the activities of detoxification enzymes, such as carboxyles erase (CarE) and glutathione S-transferase (GST) in the midgut of S. litura larvae have been studied o get an understanding of the detoxification mechanisms of S. litura larvae to excessive nickel. Results showed that CarE activities in the midgut of the 5th instar larvae decreased at lower levels of nickel (⩽5 mg/kg), while increased with increasing nickel doses at higher levels of nickel (⩾10 mg/kg) exp sure in successive 3 generations. CarE activities of the 6th instar larvae were also characterized as inhibited at low levels of nickel exposure, and improved at higher levels in the 1st generation. CarE activities of 6th instar larvae in the 2nd and 3rd generations were all lower than that in control. However, ST activities in the midgut of the 5th and 6th instar larvae all increased with increasing nickel doses (1-20 mg/kg) in diets. [ABSTRACT FROM AUTHOR]

Microphthalmia is a clinically and genetically heterogeneous disorder of eye development. The genetic basis of nonsyndromic microphthalmia is not yet fully understood. Previous studies indicated that disease pedigrees from different genetic backgrounds could be attributed to completely different gene loci. To investigate the etiology in a large autosomal-dominant inherited simple microphthalmia (nanophthalmia) pedigree, which is the first genetically analyzed Chinese microphthalmia pedigree, we performed a whole-genome scan using 382 micro-satellite DNA markers after the exclusion of reported candidates associated with microphthalmia. Strong evidence indicated that microphthalmia in this family was mapped to an unreported new locus on chromosome 2q. A significantly positive two-point LOD score was obtained with a maximum 3.290 at a recombination fraction of 0.00 for marker D2S2265. Subsequent haplotype analysis and recombination data further confined the disease-causing gene to a 15-cM interval between D2S1890 and D2S347 on 2q11-14. Our results further underlined the degree of heterogeneity in microphthalmia from Chinese background and localized a novel gene which regulates eye embryogenesis. [ABSTRACT FROM AUTHOR]

Abstract  A new gridless router to improve the yield of IC layout is presented. The improvement of yield is achieved by reducing the critical areas where the circuit failures are likely to happen. This gridless area router benefits from a novel cost function to compute critical areas during routing process, and heuristically lays the patterns on the chip area where it is less possible to induce critical area. The router also takes other objectives into consideration, such as routing completion rate and nets length. It takes advantage of gridless routing to gain more flexibility and a higher completion rate. The experimental results show that critical areas are effectively decreased by 21% on average while maintaining the routing completion rate over 99%. [ABSTRACT FROM AUTHOR]

Abstract Content-based image retrieval is an important research topic in computer vision. We present a new method that combines region of interest (ROI) detection and relevance feedback. The ROI based approach is more accurate in describing the image content than using global features, and the relevance feedback makes the system to be adaptive to subjective human perception. The feedback information is utilized to discover the subjective ROI perception of a particular user, and it is further employed to recompute the features associated with ROIs with the updated personalized ROI preference. A fast computation technique is proposed to avoid repeating the ROI detection for images in the database. It directly estimates the features of the ROIs, which makes the query process fast and efficient. For illustration of the overall approach, we use the color saliency and wavelet feature saliency to determine the ROIs. Normalized projections are selected to represent the shape features associated with the ROIs. Experimental results show that the proposed system has better performance than the global features based approaches and region based techniques without feedback. [ABSTRACT FROM AUTHOR]

The Sanjiang Plain is a vast area of alluvial floodplains and low hills in northeast Heilongjiang Province. It is the largest tract of wetlands in China and East Asia outside of Siberia. 28 wetland nature reserves exist on the Sanjiang Plain, and three of them have been listed as wetlands of international importance to water bird conservation by the Ramsar Convention Bureau. The wetlands of Sanjiang Plain are noteworthy for its rich biodiversity, but they continue to decline in area and deteriorate in quality currently. The main threats or constrains, immediate cause, root cause and required response are analyzed in this paper, and the four aspects opinion such as improvement of watershed management, enhancement of protection and restoration of habitats and biodiversity, alternative livelihoods of rural residents living in and near natural wetland reserve, and reinforcement of capacity building of natural reserves are brought forward as the effective measures for the Sanjiang Plain wetland protection. [ABSTRACT FROM AUTHOR]

Crosstalk noise is one of the emerging issues in deep sub-micrometer technology which causes many undesired effects on the circuit performance. In this paper, a Crosstalk-Aware Routing Resource Assignment (CARRA) algorithm is proposed, which integrates the routing layers and tracks to address the crosstalk noise issue during the track/layer assignment stage. The CARRA problem is formulated as a weighted bipartite matching problem and solved using the linear assignment algorithm. The crosstalk risks between nets are represented by an undirected graph and the maximum number of the concurrent crosstalk risking nets is computed as the max clique of the graph. Then the nets in each max clique are assigned to disadjacent tracks. Thus the crosstalk noise can be avoided based on the clique concept. The algorithm is tested on IBM benchmarks and the experimental results show that it can improve the final routing layout a lot with little loss of the completion rate. [ABSTRACT FROM AUTHOR]

The protective effect of carvedilol on abnormality of L-type calcium current induced by oxygen free radical in single guinea pig ventricular myocytes was studied. Whole-cell patch clamp technique was used to study the effect of H2O2 (0.5 mmol/L) on L-type calcium current in single guinea pig ventricular myocytes and the action of pretreatment with carvedilol (0.5 μmol/L). 0.5 μmol/L carvedilol had no significant effect on I Ca.L and its channel dynamics. In the presence of 0.5 mmol/L H2O2, peak current of I Ca.L was reduced significantly ( P<0.001), the I-V curve of I Ca.L was shifted upward, steady-state activation curve and steady-state deactivation curve of I Ca.L were shifted left and recovery time of I Ca.L was delayed significantly ( P<0.001). 0.5 μmol/L carvedilol significantly alleviated the inhibitory effect of H2O2 on I Ca.L as compared with that in H2O2. It was concluded that carvedilol could alleviate the abnormality of L-type calcium current induced by oxygen free radical in cardiomyocytes. It shows partly the possible mechanism of the special availability of carvedilol in chronig heart failure. [ABSTRACT FROM AUTHOR]

To elucidate the mechanism of arrhythmia in healed myocardial infarction (HMI), the changes of action potential duration (APD), transient outward potassium current (1ω), delayed rectifier potassium current (Ik) and inward rectifier potassium current (Iki) of left ventricular myocytes in non-infarcted zone of HMI were investigated. Rabbits were randomly assigned into two groups: HMI group, in which animals were subjected to thoracotomy and ligation of the circumflex coronary and sham-operated group, in which rabbits underwent thoracotomy but no conorary ligation. 3 months after the operation, the whole myocyte patch clamp technique was used to record APD, Ito Ik, and Iki of ventricular myocytes in non-infarcted zone. Our results showed that the membrane capacitance was larger in HMI group than in sham-operated group. Action potential duration was significantly lengthened in HMI group and early afterdepolarization (EAD) appeared in HMI group. The densities of Ito, Kk, tail, and Kki were reduced significantly in HMI group, from 6. 72±0.42 pA/pF, 1.54±0.13 pA/pF and 25.6±2.6 pA/pF in sham-operated group to 4.03±0.33 pA/pF, 1.14±0.11 pA/pF and 17.6±2.3 pA/pF, respectively. It is concluded that the reduced densities of Ito, Ik.tail and Iki in ventricular myocytes of non-infarcted zone in HMI were responsible for the prolongation of APD and the presentation of EAD which played important roles in the development of malignant arrhythmia in HMI. [ABSTRACT FROM AUTHOR]

Examines the stimulatory effect of splicing factors on transcriptional elongation. Interaction between spliceosomal U small nuclear ribonucleoprotein and human transcription elongation factor; Components of the transcription elongation complex; Factor to couple transcription and splicing.

Examines the functions of the human positive transcription elongation factor. Activation of P-TEFb transcription by phosphorylating ribonucleic acid polymerase II; Formation of processive elongation complexes; Presentation of data explaining the stimulatory effects of Human Immuno-deficiency Virus-1 transcription.

Since the 1950s, modern international cities have sprung up around the world and have become centers of world political and economic affairs. In the 1990s, major objectives of establishing international cities were put forward by more than forty central cities such as Beijing, Shanghai, and Guangzhou. The main theme of the 21 st century development of central cities in China will be urban modernization, internationalization, and topicalization. This study was conducted with the intention of researching the regional development strategy for the Changjiang River Delta (CRD) conurbation, with focus on the strategic development and positioning of Hangzhou, the central city of Zhejiang Province. Results from international urban studies in China and abroad were incorporated into this article from the theoretical viewpoints of urban science, regional economics and tourism economics. The findings of this study could provide some important implications for future research and practice. [ABSTRACT FROM AUTHOR]

Competition is the common ecological phenomenon that exists in a stand after canopy closure. The effect of competition on DBH, height, crown diameter and crown area of individual amur linden trees was examined. We used two plots data, from amur linden ( Tilia amurensis) plantation, 14 years old, in Liaoning province, to analyze the correlations among DBH, total height, crown diameer and crown area, and used the size-ratio of competiting tree DBHs to subject tree DBH to calculate distance-dependent competition index. The results show that DBH has the largest variation comparing with standard deviations and coeficeints. DBH and crown factors have higher correlations. Competition index is an important factor in tree growth. The best fitting models are exponent, for Cl vs height and Cl vs crown factors, and power, for Cl vs DBH. The more closed correlation model is Cl vs DBH (R2=0.7028), which performed 16.32%–18.86% better than other models. These reflect that DBH is an important indicator to display stand competition for amur linden. [ABSTRACT FROM AUTHOR]

The current difference between male and female rabbit ventricular myocytes was investigated for elucidating the mechanism of longer QT interval and higher incidence of drug-associated torsade de pointes in female rabbits than in male rabbits. Whole cell patch clamp technique was used to record APD, I to, I k, tail, I k1 and I Ca,L of myocytes from left ventricular apex. There was no difference in the membrane capacitance between male and female rabbit myocytes. APD90 was longer in female rabbits (560.4±26.5 ms, n=15) than in male ones (489.0±20.7 ms, n=14), P<0.05. In female rabbit myocytes, I K, tail, I to, I Ca, L were 0.71±0.05 pA/pF ( n=17), 8.28±1.03 pA/pF ( n=18), 24.5±3.6 pA/pF ( n=12) and 9.0±2.3 pA/pF ( n=15) respectively. In male rabbit myocytes, they were 0.84±0.07 pA/pF ( n=18), 8.60±1.20 pA/pF ( n=18), 25.9 ±4.5 pA/pF ( n=14) and 9.3±2.6 pA/pF ( n=16) respectively. I K, tail in female rabbits was significantly lower than that of male rabbits ( P<0.05), but there was no difference in I to, I Ki and I Ca, I between male rabbits and female rabbits ( P>0.05). The lower I K, tail of female rabbit myocytes may contribute to the longer repolarization and the higher incidence of drug-associated torsade de pointes. [ABSTRACT FROM AUTHOR]