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Cerebrospinal fluid-contacting neurons (CSF-cNs) act crucial role in chemosensory and mechanosensory function in spinal cord. Recently, CSF-cNs were found to be an immature neuron and may be involved in spinal cord injury recovery. But how to culture it and explore its function in vitro are not reported in previous research. Here, we first reported culture and identification of CSF-cNs in vitro. We first established a protocol for in vitro culture of CSF-cNs from the cervical spinal cord of mice within 24 h after birth. Polycystic kidney disease 2-like 1 (PKD2L1)+ cells were isolated by fluorescence-activated cell sorting and expressed the neuron marker β-tubulin III and CSF-cNs marker GABA. Intriguingly, PKD2L1+ cells formed neurosphere and expressed neural stem cell markers Nestin, Sox2 and GFAP. Thus, our research provided culture and isolation of CSF-cNs and this facilitate the investigation the CSF-cNs function in vitro. [ABSTRACT FROM AUTHOR]

We use ultrafast optical spectroscopy to study the nonequilibrium quasiparticle relaxation dynamics of the iron-based superconductor KCa2Fe4As4F2 with Tc = 33.5 K. Our results reveal a possible pseudogap (ΔPG = (2.4 ± 0.1) meV) below T* ≈ 50 K but prior to the opening of a superconducting gap (ΔSC(0) ≈ (4.3 ± 0.1) meV). Measurements under high pump fluence reveal two distinct, coherent phonon oscillations with 1.95 and 5.51 THz frequencies, respectively. The high-frequency A1g(2) mode corresponds to the c-axis polarized vibrations of FeAs planes with a nominal electron-phonon coupling constant λ A 1 g (2) = 0.194 ± 0.02 . Our findings suggest that the pseudogap is likely a precursor of superconductivity, and the electron-phonon coupling may play an essential role in the superconducting pairing in KCa2Fe4As4F2. [ABSTRACT FROM AUTHOR]

Limb-girdle muscular dystrophy (LGMD) is a group of clinically and genetically heterogeneous neuromuscular disorders. LGMD-R7, which is caused by telethonin gene (TCAP) mutations, is one of the rarest forms of LGMD, and only a small number of LGMD-R7 cases have been described and mostly include patients from Brazil. A total of two LGMD-R7 patients were enrolled at a Chinese neuromuscular center. Demographic and clinical data were collected. Laboratory investigations and electromyography were performed. Routine and immunohistochemistry staining of muscle specimens was performed, and a next-generation sequencing panel array for genes associated with hereditary neuromuscular disorders was used for analysis. The patients exhibited predominant muscle weakness. Electromyography revealed myopathic changes. The muscle biopsy showed myopathic features, such as increased fiber size variation, muscle fiber atrophy and regeneration, slight hyperplasia of the connective tissue, and disarray of the myofibrillar network. Two patients were confirmed to have mutations in the open reading frame of TCAP by next-generation sequencing. One patient had compound heterozygous mutations, and the other patient harbored a novel homozygous mutation. Western blotting analysis of the skeletal muscle lysate confirmed the absence of telethonin in the patients. We described two LGMD-R7 patients presenting a classical LGMD phenotype and a novel homozygous TCAP mutation. Our research expands the spectrum of LGMD-R7 due to TCAP mutations based on patients from a Chinese neuromuscular center. [ABSTRACT FROM AUTHOR]

Purpose: With advancements in medical imaging, more renal tumors are detected early, but it remains a challenge for radiologists to accurately distinguish subtypes of renal parenchymal tumors. We aimed to establish a novel deep convolutional neural network (CNN) model and investigate its effect on identifying subtypes of renal parenchymal tumors in T2-weighted fat saturation sequence magnetic resonance (MR) images. Methods: This retrospective study included 199 patients with pathologically confirmed renal parenchymal tumors, including 77, 46, 34, and 42 patients with clear cell renal cell carcinoma (ccRCC), chromophobe renal cell carcinoma (chRCC), angiomyolipoma (AML), and papillary renal cell carcinoma (pRCC), respectively. All enrolled patients underwent kidney MR scans with the field strength of 1.5 Tesla (T) or 3.0 T before surgery. We selected T2-weighted fat saturation sequence images of all patients and built a deep learning model to determine the type of renal tumors. Receiver operating characteristic (ROC) curve was depicted to estimate the performance of the CNN model; the accuracy, precision, sensitivity, specificity, F1-score, and area under the curve (AUC) were calculated. One-way analysis of variance and χ2 tests of independent samples were used to analyze the variables. Results: The experimental results demonstrated that the model had a 60.4% overall accuracy, a 61.7% average accuracy, and a macro-average AUC of 0.82. The AUCs for ccRCC, chRCC, AML, and pRCC were 0.94, 0.78, 0.80, and 0.76, respectively. Conclusion: Deep CNN model based on T2-weighted fat saturation sequence MR images was useful to classify the subtypes of renal parenchymal tumors with a relatively high diagnostic accuracy. [ABSTRACT FROM AUTHOR]

Novel CoFe2O4/MIL-100(Fe) (CFO/MIL-100(Fe)) core/shell nanofibers were prepared by successive ionic layer adsorption and reaction (SILAR) assembly of MIL-100(Fe) on electrospun CoFe2O4 nanofibers. The MIL-100(Fe) shells were constructed on the dispersed CoFe2O4 fiber surface with high uniformity, homogeneous thickness and high stability. Due to the inherent porosity of MIL-100(Fe), a higher specific surface area of 225.77 m2/g is achieved for the CFO/MIL-100(Fe)-10 sample. The formed CFO/MIL-100(Fe) catalysts exhibit high catalytic activity towards degradation of rhodamine B (RhB) under visible light irradiation. The photocatalytic activity remains above 77 % within 60 min illumination after four cycles. Due to the simple synthetic method, highly uniform structure, strong magnetic recoverable, as well as good photocatalytic performance, the obtained CFO/MIL-100(Fe) core/shell nanofibers could be promising photocatalysts for practical application. [ABSTRACT FROM AUTHOR]

Objective: To investigate specific muscle pathologies of different kinds of myositis-specific autoantibodies (MSAs) in idiopathic inflammatory myopathy (IIM) patients. Methods: One hundred eleven Chinese patients from Xiangya Hospital, Central South University diagnosed with IIMs according to European Neuromuscular Centre (ENMC) criteria were included. Clinical manifestation, myositis-specific autoantibodies, and histologic findings were evaluated to explore the pattern of necrosis, regeneration, and perifascicular atrophy, inflammatory cells in IIM patients with different MSAs. Results: Anti-SRP group has the lowest muscle strength scores, the highest creatine kinase levels, the most severe degree of necrosis and regeneration (1.90[0.80–3.95], 1.00[0.30–1.71]), and the lowest positive rate of MHC-I staining (35.71%). The anti-MDA5 group demonstrates the mildest pathological changes, with the fewest necrotic and regenerated muscle fibers (0.00[0.00–0.50], 0.00[0.00–0.00]), and the fewest inflammatory cell infiltration, and the highest muscle strength scores. The anti-NXP2 group has the most frequent inflammatory infiltrates, especially CD4+ T cells (31.14[15.00–39.00]). The patients with anti-NXP2 and the anti-TIF1γ antibodies show higher frequency of punched-out fibers (1.50[0.00–3.70], 0.00[0.00–1.00]) and perifascicular atrophy (71.43%, 55.56%). As for anti-synthetase antibodies (ASAs), the anti-Jo-1 group shows the most frequent rate of perifascicular necrosis (60%), while other ASA groups do not show perifascicular necrosis. Conclusions: Of the MSAs, the anti-SRP antibody leads to the most severe muscle involvement, while the anti-MAD5 antibody the mildest. The anti-NXP2 and anti-TIF1γ groups have the most typical "DM" pathology. Key Points • Anti-SRP group shows severe muscle pathology while anti-MDA5 group shows the mildest. • Anti-NXP2 group has the most frequent inflammatory infiltrates. Pouch-out fibers and perifascicular atrophy are more prevalent in anti-NXP2 and anti-TIF1γ groups. • Anti-Jo-1 group is often accompanied by perifascicular necrosis, while other anti-synthetase antibody groups are not. [ABSTRACT FROM AUTHOR]

A design problem with deficient information is generally described as wicked or ill-defined. The information insufficiency leaves designers with loose settings, free environments, and a lack of strict boundaries, which provides them with more opportunities to facilitate innovation. Therefore, to capture the opportunity behind the uncertainty of a design problem, this study models an innovative design as a composite solving process, where the problem is clarified and resolved from fuzziness to satisfying solutions by interplay among design problems, knowledge, and solutions. Additionally, a triple-helix structured model for the innovative product design process is proposed based on the co-evolution of the problem, solution, and knowledge spaces, to provide designers with a distinct design strategy and method for innovative design. The three spaces interact and co-evolve through iterative mappings, including problem structuring, knowledge expansion, and solution generation. The mappings carry the information processing and decision-making activities of the design, and create the path to satisfying solutions. Finally, a case study of a reactor coolant flow distribution device is presented to demonstrate the practicability of this model and the method for innovative product design. [ABSTRACT FROM AUTHOR]

Herein, novel fibrous Bi4Ti3O12/Bi2S3/MoS2 is constructed by a simple one-step methodology for photocatalytic degradation of RhB dyes. Bi4Ti3O12/Bi2S3/MoS2 hybrid fibers were facilely prepared by direct hydrothermal growth of MoS2 nanosheets on electrospun Bi4Ti3O12 nanofiber surface, during which rod-like Bi2S3 was formed by in-situ ion exchange reaction between BTO and S source. The MoS2 nanosheets with several-layer thickness uniformly are coated both on the BTO and Bi2S3 surface. Remarkable enhancement of visible light absorption and photo-generated charge separation in Bi4Ti3O12/Bi2S3/MoS2 are achieved compared with the bare BTO nanofibers. By changing the weight ratio of Mo/S and the precursor dosage of MoS2, the optimized BM-150/250 sample presents 2.3 and 4.1 times higher of the photodegradation efficiency and apparent reaction rate constant, respectively, than that of pure BTO fibers after 120-min irradiation under visible light. The system pays an efficient pathway to establish ternary composite fibers providing high photocatalytic activity for other electrospun Bi-contained nanofibers. [ABSTRACT FROM AUTHOR]

The melon fly, Zeugodacus cucurbitae (Coquillett), is an important destructive pest worldwide. Functional studies of the genes associated with development and reproduction during different life stages are limited in Z. cucurbitae. There have yet to be comprehensive transcriptomic resources for genetic and functional genomic studies to identify the molecular mechanisms related to its development and reproduction. In this study, we comprehensively sequenced the transcriptomes of four different developmental stages: egg, larva, pupa, and adults. Using the Illumina RNA-Seq technology, we constructed 52 libraries from 13 stages with four biological replicates in each and generated 435.61 Gb clean reads. We comprehensively characterized the transcriptomes with high-coverage mapping to the reference genome. A total of 13,760 genes were mapped to the reference genome, and another 4481 genes were characterized as new genes. Finally, 14,931 genes (81.85%) were functionally annotated against six annotation databases. This study provides the first comprehensive transcriptome data of all developmental stages of Z. cucurbitae, and will serve as a valuable resource for future genetic and functional studies. Measurement(s) RNA • sequence_assembly • sequence feature annotation • gene expression Technology Type(s) RNA sequencing • sequence assembly process • sequence annotation • Expectation-Maximization(EM) algorithm Factor Type(s) biological replicate • developmental stage • sex Sample Characteristic - Organism Zeugodacus cucurbitae Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.11698254 [ABSTRACT FROM AUTHOR]

Grain growth in porous ceramics is a complex process due to the variety of interactions between pores and grains. In this study, the pore deformation and grain boundary migration during porous ceramic sintering are simulated by the phase-field method, and the variety of diffusions during sintering is considered. Pores of different shapes and sizes are induced into the simulations to investigate the grain boundary migration and pore deformations during grain growth. Simulation results indicate that the porous microstructure is determined by the contacting mode between pore surface and grain boundaries, which is in good agreement with experimental observations. The efficiency of the grain boundary migration is analyzed via calculating the forces applied on the interfaces between grains and pores, and the mechanism of the pore deformation during grain boundary migration is discussed. Therefore, controlling the grain-pore microstructure by adjusting the synthesis process is essential to reach the desired mechanical and physical properties of sintered materials. [ABSTRACT FROM AUTHOR]

Replicative senescence of vascular smooth muscle cells (VSMCs) contributes to aging as well as age-related cardiovascular diseases. Rapamycin can delay the onset of aging-related diseases via inhibition of the mammalian target of rapamycin (mTOR), but its role in vascular aging remains elusive. This study investigated the involvement of mTOR signaling in replicative senescence of VSMCs. Replicative senescence was induced by the extended passages of human VSMCs. Aging-related cell morphology was observed. The aging-related proteins and enzyme activity, and oxidative stress were measured. Significant increase in SA-β-gal activity and protein expression, p53 and p16 protein expression, proliferation index (PI), malondialdehyde (MDA) concentration, superoxide dismutase (SOD) and glutathione peroxidase (GPX) activity, and significant decrease in telomerase activity was observed in aging VSMCs compared to young cells. Significant activation of PI3K/Akt/mTOR signaling was observed in aging cells but not young cells. Pretreatment of VSMCs with PI3K inhibitor blocked while PI3K activator increased the changes of the above replicative senescence-related parameters in VSMCs. Rapamycin and silencing of mTOR expression inhibited replicative senescence in VSMCs through decreasing the level of p-mTOR Ser, p-mTOR Thr, and S6K1 phosphorylation. This study for the first time demonstrated that the PI3K/Akt/mTOR/S6K1 signal pathway plays an important role in regulating replicative senescence of human VSMCs. [ABSTRACT FROM AUTHOR]

The West Development Program, initiated in 2000 by the central government of China, has attracted huge investments in the arid and semiarid regions of northwest China. As a consequence of this development, environmental pollution and ecological degradation have been widely reported. The Silk Road economic belt proposed by China promotes further economic development in the regions, but rational planning and regular monitoring are essential to minimize any additional negative impacts of the anthropogenic activities. This article reports an investigation on the distribution, enrichment and sources of trace metals in the topsoil in and around the Ningxia Hengli Steel Wire Plant (HSWP) situated along the Silk Road economic belt. The concentrations of Cd, Pb, Cr, Cu, Zn, Ni, Mn, V and Co in the surface soils of the study area vary, respectively, in the following ranges: 0.083-18.600, 21.9-2681.0, 58.0-100.0, 14.6-169.9, 59.0-4207.3, 19.3-40.8, 411-711, 55.2-76.6 and 7.46-25.21 mg/kg. The concentrations of Cd, Pb, Cr, Cu, Zn and Co are significantly higher than their local background values. Pollution levels of these trace metals in the surface soils were assessed using contamination index (Cif), geo-accumulation index (Igeo), modified contamination degree (mCd) and pollution load index. The potential ecological risks caused by the metal pollution were assessed by means of potential ecological risk factor (Eif) and potential ecological risk index. The Spearman correlation and cluster analysis were applied to determine the contamination sources. The HSWP zone, associated with very high potential ecological risk caused by Pb and Cd, is more seriously contaminated by trace metals than the residential zone. This study indicates that Cd, Pb, Cu, Zn and Co mainly originate from industrial pollution, whereas Cr, Mn, Ni and V result from both industrial activities and natural processes. [ABSTRACT FROM AUTHOR]

Objective: Human umbilical cord mesenchymal stem cells (hUCMSCs) have renoprotective effects but the influence of the microenvironment on characteristics of hUCMSCs has not been well studied. Here, we investigate the effects of injury conditions on properties of hUCMSCs. Results: hUCMSCs were treated in vitro under conditions mimicking the injury microenvironment of acute kidney injury. Cells stimulated with factor-treated medium proliferated slowly at first but quickly afterwards their morphology subsequently changed from spindle to stellate shape. Increased number of cells with strong expression of thymine-1 (Thy-1) or α-smooth muscle actin (α-SMA) was detected at 1 or 2 weeks after stimulation. Hepatocyte growth factor (HGF) level markedly increased after culture for 6 h under hypoxia condition. The expressions of HGF and insulin growth factor-1 (IGF-1) were significantly up-regulated from 0.22 ± 0.03 to 0.9 ± 0.02 and 0.07 ± 0.03 to 0.19 ± 0.01 in H/R-treated hUCMSCs respectively. Co-culture with injured renal tubular epithelial cells significantly promoted the expression of HGF (1.19 ± 0.21) and IGF-1 (0.24 ± 0.03) in hUCMSCs. Conclusion: The characteristics of hUCMSCs change in response to inured conditions, which may enhance the efficacy of stem cell therapy and provide novel strategies in maximizing biological and functional properties of hUCMSCs [ABSTRACT FROM AUTHOR]

A mortality rate higher than 90 % was observed in a larva-rearing facility for Pacific cod, Gadus macrocephalus, in China. Larvae showing clinical signs of infection were collected. Initial suspicion of nervous necrosis virus (NNV) infection was confirmed by sequencing, absolute quantification real-time PCR (A-qPCR), and electron microscopy. The nucleotide sequence of RNA2 was 1,375 bases long (GenBank no. KM576685), coding for a single ORF corresponding to the capsid protein from residues 21 to 1034. Phylogenetic analysis of the capsid protein sequence showed that PCNNV belongs to the barfin flounder NNV (BFNVV) genotype. An amino acid sequence alignment revealed 39 differences between the cold- and warm-resistant viral groups, suggesting that PCNNV evolved under temperature selection. The 3-D structure of the predicted capsid protein was modeled to identify potential epitopes, and the gene was expressed in Escherichia coli, yielding a protein with a molecular mass of 55 kDa. During PCNNV outbreaks, the viral copy number was found to reach 10 per ng of total RNA, which could be considered the lethal copy number of NNV in cod. The gonads, eggs, fertilized eggs and asymptomatic cod fry were all positive for PCNNV, indicating viral vertical transmission as the main source of the viral load. The amount of virus in the apparent healthy fry or survivors seemed to decrease gradually with development. These results might lead to efficient diagnostic methods to help farmers select NNV-free broodfish for cod breeding. [ABSTRACT FROM AUTHOR]

The gene encoding the fibrinolytic enzyme (PPFE-I) from Paenibacillus polymyxa EJS-3 was cloned and sequenced (Genbank No. KC176802). The 1773 bp gene encoded 590 amino acids and had low homology with other known fibrinolytic enzymes. PPFE-I was soluble and expressed in E. coli BL21 to enhance the activity. The recombinant enzyme (rPPFE-I) was purified to homogeneity, and enzymatic properties were characterized. The optimal temperature and pH for rPPFE-I were 37°C and 7.5, respectively. Observed activities of rPPFE-I were highest in the presence of Zn2+, Mg2+, and Fe2+ and the lowest in the presence of Ca2+ and Cu2+. The rPPFE-I activity was strongly inhibited by PMSF. The α-chain was affected by the rPPFE-I cleavage speed of fibrinogen, followed by the b and γ chains. The inhibitory effects of rPPFE-I against ADP-induced human platelet aggregation were dosedependent with an IC50 value of 1.54 μM. [ABSTRACT FROM AUTHOR]

Sensitivity analysis is becoming increasingly widespread in many fields of engineering and sciences and has become a necessary step to verify the feasibility and reliability of a model or a method. The sensitivity of the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method in water quality assessment mainly includes sensitivity to the parameter weights and sensitivity to the index input data. In the present study, the sensitivity of TOPSIS to the parameter weights was discussed in detail. The present study assumed the original parameter weights to be equal to each other, and then each weight was changed separately to see how the assessment results would be affected. Fourteen schemes were designed to investigate the sensitivity to the variation of each weight. The variation ranges that keep the assessment results unchangeable were also derived theoretically. The results show that the final assessment results will change when the weights increase or decrease by ±20 to ±50 %. The feedback of different samples to the variation of a given weight is different, and the feedback of a given sample to the variation of different weights is also different. The final assessment results can keep relatively stable when a given weight is disturbed as long as the initial variation ratios meet one of the eight derived requirements. [ABSTRACT FROM AUTHOR]

This is the second part of the study on sensitivity analysis of the technique for order preference by similarity to ideal solution (TOPSIS)method inwater quality assessment. In the present study, the sensitivity of the TOPSIS method to the index input data was investigated. The sensitivity was first theoretically analyzed under two major assumptions. One assumption was that one index or more of the samples were perturbed with the same ratio while other indices kept unchanged. The other one was that all indices of a given sample were changed simultaneously with the same ratio, while the indices of other samples were unchanged. Furthermore, a case study under assumption 2 was also carried out in this paper. When the same indices of different water samples are changed simultaneously with the same variation ratio, the final water quality assessment results will not be influenced at all. When the input data of all indices of a given sample are perturbed with the same variation ratio, the assessment values of all samples will be influenced theoretically. However, the case study shows that only the perturbed sample is sensitive to the variation, and a simple linear equation representing the relation between the closeness coefficient (CC) values of the perturbed sample and variation ratios can be derived under the assumption 2. This linear equation can be used for determining the sample orders under various variation ratios. [ABSTRACT FROM AUTHOR]

Cancer stem cells (CSCs) have the characteristics of self-renewal, unlimited proliferation, and initiating new tumors. However, the origin of CSCs is still controversial. F6, a tumor cell line transformed from human fetal mesenchymal stem cells, was established in our previous study. Whether CSCs exist in this mutated cell line remains unclear. In the present study, we isolated CSCs from F6 cells based on CD133 expression using flow cytometry and investigated the biological characteristics of CD133+ F6 cells (F6-CD133+). We observed that the F6-CD133+ cells grew faster and had a higher capacity of colony formation than the F6-CD133− cells and parental F6 cells in vitro. In addition, F6-CD133+ cells had a higher tumorigenic ability than F6-CD133− cells in vivo since 1,000 F6-CD133+ cells were able to form tumors in nude mice. Cell viability assay revealed that F6-CD133+ cells were more sensitive to cisplatin while less to 5-fluorouracil. Furthermore, gene expression profile analysis showed that there were 673 differentially expressed genes between F6-CD133+ and F6-CD133− cells, many of which were involved in key cell signaling pathways. Taken together, our findings confirm that F6 cells contain a population of CSCs that contribute to its heterogeneity and tumorigenic potential, indicating that transformed stem cells could be the source of CSCs, and targeting this population may lead to more effective tumor treatments. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs) are candidates for cell therapy of kidney diseases. However, the application of MSC derived from human umbilical cord (UC-MSC) in treating acute renal failure (ARF) has not been reported. UC-MSCs, 106, were transplantated via the left carotid artery into ARF rats which was established by clamping bilateral pedicles for 60 min and reperfusing. Serum creatinine and urea nitrogen decreased 4.8 times and 3.6 times as well as caspase-3 and IL-1β decreased 5.8 times and 9 times compared to control groups, respectively. The percent of proliferative cell nuclear antigen (PCNA)-positive cells (53% ± 7.5%) was higher than that in the control groups (17% ± 4.5%). In addition, the transplanted UC-MSCs could reside in local injury sites, leading to the relief of hyperemia and inflammation, but no obvious transdifferentiation into renal-like cells. The results lay the foundation for further study on the potential application of UC-MSC in human disease. [ABSTRACT FROM AUTHOR]

Objective The objective of this study was to investigate the efficacy of mesenchymal stem cell (MSC) in the treatment of arthritis. Methods Mesenchymal stem cells were injected intravenously into mice with collagen-induced arthritis (CIA). Arthritic indexes were evaluated, and the levels of the proand anti-inflammatory cytokines interleukin-10 (IL-10), gamma interferon (IFN-γ)-inducible protein 10 (IP-10), chemokine (C-X-C motif) receptor 3 (CXCR3), interleukin-17A (IL-17A), and tumor necrosis factor α (TNF-α) in serum or splenic cells were determined using real-time RT-PCR, Western blotting, and enzyme-linked immunosorbent assay (ELISA). The proliferation of dendritic cell line D2SC cells was determined using ³H-TdR incorporation assay. Results Upon injection of MSCs, overall arthritis symptoms were significantly improved in the CIA mouse models as indicated by the paw edema. Consistent with this observation, serum levels of pro-inflammatory cytokine TNF-α and inflammatory cell infiltration decreased significantly 12 days after MSC injection, while the expression of anti-inflammatory cytokines IL-10, IP-10, and CXCR3 was increased in splenocytes. In addition, we provided evidence that MSCs may directly promote the proliferation of D2SC cells and the expression of IP-10 in D2SC cells in vitro. Conclusion Mesenchymal stem cells significantly enhance the efficacy of collagen-induced arthritis treatment, likely through the modulation of the expression of various cytokines. [ABSTRACT FROM AUTHOR]

Abstract  Collaborative social annotation systems allow users to record and share their original keywords or tag attachments to Web resources such as Web pages, photos, or videos. These annotations are a method for organizing and labeling information. They have the potential to help users navigate the Web and locate the needed resources. However, since annotations are posted by users under no central control, there exist problems such as spam and synonymous annotations. To efficiently use annotation information to facilitate knowledge discovery from the Web, it is advantageous if we organize social annotations from semantic perspective and embed them into algorithms for knowledge discovery. This inspires the Web page recommendation with annotations, in which users and Web pages are clustered so that semantically similar items can be related. In this paper we propose four graphic models which cluster users, Web pages and annotations and recommend Web pages for given users by assigning items to the right cluster first. The algorithms are then compared to the classical collaborative filtering recommendation method on a real-world data set. Our result indicates that the graphic models provide better recommendation performance and are robust to fit for the real applications. [ABSTRACT FROM AUTHOR]

Abstract  Excessive proliferation of vascular smooth cells (VSMCs) plays a critical role in the pathogenesis of diverse vascular disorders, and inhibition of VSMCs proliferation has been proved to be beneficial to these diseases. In this study, we investigated the antiproliferative effect of B-type natriuretic peptide (BNP), a natriuretic peptide with potent antioxidant capacity, on rat aortic VSMCs, and the possible mechanisms involved. The results indicate that BNP potently inhibited AngiotensinII (AngII)-induced VSMCs proliferation, as evaluated by [3H]-thymidine incorporation assay. Consistently, BNP significantly decreased AngII-induced intracellular reactive oxygen species (ROS) and NAD(P)H oxidase activity. 8-Br-cGMP, a cGMP analog, mimicked these effects. To confirm its mechanism, siRNA of natriuretic peptide receptor-A(NRPA) strategy technology was used to block cGMP production in VSMCs, and siNPRA attenuated the inhibitory effects of BNP in VSMCs. Taken together, these results indicate that BNP was capable of inhibiting VSMCs proliferation by NPRA/cGMP pathway, which might be associated with the suppression of ROS production. These results might be related, at least partly, to the anti-oxidant property of BNP. [ABSTRACT FROM AUTHOR]

A combined study of mineral O and Rb–Sr isotopes was carried out for a number of Mesozoic granitoids in China in order to compare the degree of O isotope equilibrium between coexisting minerals, with the validity of mineral Rb–Sr isochrons for granitoids. A scrutiny of both O isotope geothermometry and Rb–Sr internal isochron dating for corresponding minerals indicates that equilibrium O isotope fractionation between Rb–Sr isochron minerals corresponds to geologically meaningful isochron ages if the variation in 87Rb/86Sr ratio is big enough to provide reasonably small uncertainties in age. Significant deviation of the Rb–Sr isochron age from the actual age appears to depend on the difference in Sr isotopic composition between an external fluid and the igneous minerals. As a result, O isotope disequilibrium is often caused by interaction between the rock and the external fluid that results in mineral alteration. Post-magmatic alteration can cause isotope exchange between the minerals and an internally buffered fluid that is isotopically identical to the host rock. The O isotope composition of coexisting minerals in studied samples changed principally due to a decrease in temperature. Both Rb and Sr concentrations and the Sr isotope ratios of isochron minerals also changed due to the mixing of different Sr reservoirs. Nevertheless, the isochron age can remain unchanged if the mixing took place along the isochron chord between the internal fluid and the minerals from that newly altered minerals formed. This provides an insight into the effect of internal and external fluids on the validity of mineral Rb–Sr chronometry. In addition, an alternative approach is proposed to construct the cooling curve by a combined use of O isotope temperature and mineral isotope age for the granitoids of interest. Comparing with the traditional method using the empirical closure temperature for Rb–Sr chronometry, the proposed approach utilizes fewer variables with smaller uncertainties than the traditional way. [ABSTRACT FROM AUTHOR]