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Li2MoO3 (LMO) is a promising stabilization block for constructing high performance lithium-rich layered oxides. However, its poor electronic conductivity, surface instability in air, and capacity degradation are drawbacks for the application. To solve these issues, non-equivalent Nb5+ dopants were introduced into the LMO lattice. Density functional theory (DFT) calculations combined with experimental characterizations have confirmed that Nb5+ doping not only enhances the Mo–O bonds of LMO but also reduces its band gap and further suppresses the oxidation of surface Mo4+, leading to a much-improved lattice and surface stabilities. Therefore, the electrochemical performances of LMNO are improved obviously. The initial discharge capacities of LMO, LMNO-0.01, LMNO-0.02, and LMNO-0.03 are 232.6, 234.7, 251.6, and 246.3 mAh·g−1, respectively. LMNO-0.02 exhibits the best performance, and its specific capacities at the 1st and 100th cycles reach 144.13 and 72.06 mA g−1 under a 3C charging rate and a 5C discharging rate. Our results have demonstrated that non-equivalent cationic doping is an effective strategy to modulate the bonding characteristics of LMO and therefore to improve its electrochemical performance.

To investigate the prevalence of anxiety and depressive symptoms and the associated risk factors among first-line medical staff in Wuhan during the coronavirus disease 2019 (COVID-19) epidemic. From March 5 to 15, 2020, the Hamilton Anxiety Scale and Hamilton Depression scale were used to investigate the anxiety and depression status of medical staff in Wuhan Cabin Hospital (a Hospital). Two hundred seventy-six questionnaires were received from 96 doctors and 180 nurses, including 79 males and 197 females. During the COVID-19 epidemic, the prevalence rate of anxiety and depression was 27.9% and 18.1%, respectively, among 276 front-line medical staff in Wuhan. The prevalence rate of anxiety and depression among doctors was 19.8% and 11.5%, respectively, and the prevalence rate of anxiety and depression among nurses was 32.2% and 21.7%, respectively. Females recorded higher total scores for anxiety and depression than males, and nurses recorded higher scores for anxiety and depression than doctors. During the COVID-19 epidemic, some first-line medical staff experienced mental health problems such as depression and anxiety. Nurses were more prone to anxiety and depression than doctors. Effective strategies toward to improving the mental health should be provided to first-line medical staff, especially female medical staff and nurses.

OBJECTIVE: To study the role of vascular endothelial growth factor-A (VEGF-A) in pulmonary vascular remodeling in neonatal rats with hypoxic pulmonary hypertension (HPH) by regulating survivin (SVV). METHODS: A total of 96 neonatal rats were randomly divided into three groups: HPH+VEGF-A group, HPH group, and control group. Each group was further randomly divided into 3-, 7-, 10-, and 14-day subgroups (n=8 in each subgroup). The neonatal rats in the HPH+VEGF-A and HPH groups were intratracheally transfected with adenoviral vectors with or without VEGF-A gene respectively. Those in the control group were given intratracheal injection of normal saline and were then fed under normoxic conditions. The direct measurement method was used to measure mean right ventricular systolic pressure (RVSP). Hematoxylin-eosin staining was used to observe the morphological changes of pulmonary vessels under a light microscope and calculate the percentage of media wall thickness (MT%) and the percentage of media wall cross-sectional area (MA%) in the pulmonary arterioles. Immunohistochemistry was used to measure the expression levels of VEGF-A and SVV in lung tissue. RESULTS: The HPH group had a significantly higher mean RVSP than the control and HPH+VEGF-A groups at each time point (P < 0.05). Pulmonary vascular remodeling occurred in the HPH group on day 7 of hypoxia, while it occurred in the HPH+VEGF-A group on day 10 of hypoxia. On day 7 of hypoxia, the HPH group had significantly higher MT% and MA% than the control and HPH+VEGF-A groups (P < 0.05). On days 10 and 14 of hypoxia, the HPH and HPH+VEGF-A groups had significantly higher MT% and MA% than the control group (P < 0.05). The HPH and HPH+VEGF-A groups had significantly higher expression of VEGF-A than the control group at each time point (P < 0.05). On days 3 and 7 of hypoxia, the HPH+VEGF-A group had significantly higher expression of VEGF-A than the HPH group (P < 0.05). On day 14 of hypoxia, the HPH group had significantly higher expression of SVV than the control group (P < 0.05). The HPH+VEGF-A group had significantly higher expression of SVV than the control group at each time point (P < 0.05). On days 3 and 7 of hypoxia, the HPH+VEGF-A group had significantly higher expression of SVV than the HPH group (P < 0.05). CONCLUSIONS: Prophylactic intratracheal administration of exogenous VEGF-A in neonatal rats with HPH can inhibit pulmonary vascular remodeling and reduce pulmonary arterial pressure by upregulating the expression of SVV in the early stage of hypoxia. This provides a basis for the interventional treatment of pulmonary vascular remodeling in neonatal HPH.

To investigate the anxiety and depression of patients with the coronavirus disease 2019 (COVID-19) who participated in Baduanjin exercise. From February 20, 2020 to March 7, 2020, the Hospital Anxiety and Depression scale (HAD) were used to investigate the anxiety and depression levels of patients with COVID-19 who participated in Baduanjin exercise. Ninety one questionnaires were received, including 40 males and 51 females. Stepwise regression analysis was used to analyze the effects of related factors on anxiety and depression levels. In Square cabin hospital, 91% of patients participated in Baduanjin exercise had no obvious anxiety and 82% had no obvious depression. The scores of anxiety and depression of female patients were significantly higher than that of male patients. Bachelor degree or above with low scores for anxiety and depression. The frequency of Baduanjin exercise was negatively correlated with anxiety and depression score. The development of Baduanjin exercise has a certain positive influence on the COVID-19 patients in the Square cabin hospital, which is conducive to alleviate anxiety and depression symptoms of the patients.

Aim This study aimed to determine whether serum ferritin (SF) is an independent risk factor of the incidence of chronic kidney disease (CKD) and rapid renal function decline (RFD) in male Tibetan patients with type 2 diabetes mellitus (T2DM). Methods We performed a retrospective cohort study that included 191 male Tibetan patients with T2DM without CKD. Patients were divided into three groups according to the level of SF. The following outcomes were measured: cumulative incidence of chronic kidney disease [i.e. estimated glomerular filtration rate (eGFR)

User activity fluctuations reflect the performance of online society. We investigate the statistical properties of 1-min user activity time series of simultaneously online users inhabited in 95 independent virtual worlds. The number of online users exhibits clear intraday and weekly patterns due to human's circadian rhythms and week cycles. Statistical analysis shows that the distribution of absolute activity fluctuations has a power-law tail for 44 virtual worlds with an average tail exponent close to 2.15. The partition function approach unveils that the absolute activity fluctuations possess multifractal features for all the 95 virtual worlds. For the sample of 44 virtual worlds with power-law tailed distributions of the absolute activity fluctuations, the width of singularity $\Delta\alpha$ is negatively correlated with the maximum activity ($p$-value=0.070) and the time to the maximum activity ($p$-value=0.010). The negative correlations are not observed for neither the other 51 virtual worlds nor the whole sample of the 95 virtual worlds. In addition, numerical experiments indicate that both temporal structure and large fluctuations have influence on the multifractal spectrum. We also find that the temporal structure has stronger impact on the singularity width than large fluctuations., Comment: 9 pages including 8 figures

This study was conducted to determine the differences and changes in trends of physiological metabolism in the process of adaptation to saline environments and artificial domestication among the subgenus Soja. Glycine max, Glycine gracilis and Glycine soja were used as the experimental material. The determination of mineral contents during different growth periods and the photosynthetic pigments, gas exchange parameters and soluble carbohydrate contents in the initial bloom stage were investigated. The results showed that, NO3, H2PO4, Cu, Zn and B contents and the photosynthetic pigments, gas exchange parameters and photosynthetic product were significantly higher in salt-tolerant wild soybean than in common wild soybean. NO3, H2PO4, SO4, K, Mg, Fe, Cu, Mo and Mn contents were significantly lower in cultivated soybean than in common wild soybean; and Ca and B were significantly higher. The photosynthetic pigments, gas exchange parameters and photosynthetic product at the initial bloom stage in cultivated soybean were significant higher than in common wild soybean and semi-wild soybean. The correlations of H2PO4, SO4, K, Mg, Mo and Mn with photosynthetic characteristic parameters significantly differed among members of Soja. Our study confirmed that mineral contents and photosynthetic characteristics among Soja had evolved towards the different environments and human requirements during long-term natural selection and artificial domestication. These findings will contribute to understanding the evolutionary trend of soybean. © 2016 Friends Science Publishers

The thermodynamic stabilities, surface morphologies, and electronic structures of the LiTi2O4 compound were investigated by the first-principles methods. The formation enthalpies and lattice constants of LixTi2O4 decrease at first and then increase again. This phenomenon is related to the balance between Li O attractions and Li Li repulsions. Population analysis revealed that pure ionic and strong covalent bonds are formed respectively between lithium and oxygen and between titanium and oxygen in LiTi2O4 material. These interactions are very crucial for the thermodynamic stability of the compounds. The surface stability was considered as functions of the chemical potentials, and five terminations, (100)-Ti2O4, (110)-Ti2O4, (210)-Ti2O4, (111)-LiTiO4, and (310)-Ti2O8ones, are dominant in the stability diagram. Our calculation showed that a particle morphology with mono (110) facet can be obtained at Ti- and/or O-moderate conditions, and this morphology will be very helpful for improving the rate performance of the material via reduction of the lithium diffusion distance. Furthermore, partially filled electronic states at the Fermi energy were confirmed for bulk LiTi2O4 and some of the surfaces, and they are responsible for the excellent electronic conductivity of the material. Further calculations showed that the work functions are sensitive to the stoichiometry of the surfaces.

With the development of Internet of Things technology, cloud computing technology, big data technology, and artificial intelligence technology, the application of these new technologies to rural life can help rural elderly care at home. The home care system for the elderly in rural areas is based on artificial intelligence technology and uses the Internet of things technology to collect real-time environmental parameters at home and to optimize the living environment. It uses intelligent image recognition technology to judge the behavior of the elderly and interlopers and gives effective early warning and alarm. It uses wearable devices to measure the health of the elderly in real-time. It uses the man-machine dialogue program to solve the life needs of the elderly to improve the well-being of the elderly life. It integrates big data and cloud computing technology to process the collected information.

Chemokines and their receptors play an important role in the pathogenesis of acute and chronic diabetic nephropathy (DN). However, their expression pattern and function in glomerular podocytes have not been investigated as of yet. In the present study, we investigated whether CXCR3 could protect podocytes from high glucose-induced apoptosis and inflammatory cytokine production and explored the possible mechanism. Cell viability, cell cycle and apoptosis were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry, respectively. The level of intracellular reactive oxygen species (ROS) and mitochondrial membrane potential (∆Ψm) was measured using a dichlorofluorescein diacetate (DCFH-DA) ortetrechloro-tetraethylbenzimidazol carbocyanine iodide (JC-1) fluorescent probe, respectively. Quantitative real-time PCR was used to determine the gene expression of CXCR3. Western blots were carried out for the related protein expression in podocytes, including CXCR3, Nephrin, Podocin, Bcl-2, Bax, and Caspase-3. Firstly, we found that CXCR3 expression was significantly up-regulated and cell viability was decreased in high glucose (HG)-treated mouse podocytes in a dose-dependent manner. Secondly, knockdown of CXCR3 in mouse podocytes significantly suppressed HG-induced viability decrease, cell cycle arrest, ROS generation and ∆Ψm reduction. Moreover, knockdown of CXCR3 reduced the podocytes injury in cell apoptosis and inflammation through increasing the expression of Nephrin, Podocin and Bcl-2, and decreasing the expression of Bax and Caspase-3. In conclusion, CXCR3 knockdown protected podocytes from HG-induced apoptosis and inflammation in vitro, suggesting that inhibition of CXCR3 may have a therapeutic potential in DN treatment.

Hypoxia-inducible factor (HIF)-1α is associated with hypoxia-induced pulmonary hypertension (HPH) in adults. In the present study, the expression levels of HIF-1α, endothelin (ET)-1 and adrenomedullin (ADM) were analyzed during HPH in neonates. In total, 96 newborn rats were subjected to hypoxia or normoxia for 3, 5, 7, 10, 14 or 21 days (n=8 per subgroup). HIF-1α, ET-1 and ADM expression levels were measured by quantitative polymerase chain reaction. In addition, the intima-media thickness/external diameter ratio (MT%) and medial wall cross-sectional area/vessel total cross-sectional area ratio (MA%) were calculated to evaluate pulmonary vascular remodeling. The mean pulmonary arterial pressure (mPAP) increased with exposure to hypoxia. Furthermore, the expression levels of HIF-1α, ET-1 and ADM in the lungs were shown to increase after three and five days of hypoxia, while the MT% and MA% increased after seven days of hypoxia, as compared with the controls (P

Similar to charitable giving in real world, donation behaviors play an important role in the complex interactions among individuals in virtual worlds. However, it is not clear if the donation process is random or not. We investigate this problem using detailed data from parallel virtual worlds adhered to a massively multiplayer online role-playing game. We find that the inter-donation durations follow power-law-tailed distributions distributed with an average tail exponent close to 1.91, have strong long-range correlations, and possess multifractal features. These findings indicate that the donation process is non-Poissonian, which has potential worth in modeling the complicated individuals behaviors in virtual worlds., Comment: 16 pages including 5 figures

The transfer of football players is an important part in football games. Most studies on the transfer of football players focus on the transfer system and transfer fees but not on the transfer behavior itself. Based on the 470,792 transfer records from 1990 to 2016 among 23,605 football clubs in 206 countries and regions, we construct a directed footballer transfer network (FTN), where the nodes are the football clubs and the links correspond to the footballer transfers. A systemic analysis is conduced on the topological properties of the FTN. We find that the in-degrees, out-degrees, in-strengths and out-strengths of nodes follow bimodal distributions (a power law with exponential decay), while the distribution of link weights has a power-law tail. We further figure out the correlations between node degrees, node strengths and link weights. We also investigate the general characteristics of different measures of network centrality. Our network analysis of the global footballer transfer market sheds new lights into the investigation of the characteristics of transfer activities., 7 pages, 6 figures

OBJECTIVE: To investigate the protective effect of heat shock protein 70 (HSP70) against hypoxic pulmonary hypertension (HPH) in neonatal rats. METHODS: A total of 128 neonatal rats were randomly divided into blank control group, HPH model group, empty virus group, and HSP70 group, with 32 rats in each group. Before the establishment of an HPH model, the rats in the blank control group and HPH model group were given caudal vein injection of 5 μL sterile saline, those in the empty virus group were given caudal vein injection of 5 μL Ad-GFP (1 010 PFU/mL), and those in the HSP70 group were given caudal vein injection of 5 μL Ad-HSP70 (1 010 PFU/mL). HPH model was prepared in the HPH model, empty virus, and HSP70 groups after transfection. At 3, 7, 10, and 14 days after model establishment, a multi-channel physiological recorder was used to record mean pulmonary arterial pressure (mPAP), optical and electron microscopes were used to observe the structure and remodeling parameters of pulmonary vessels, and Western blot was used to measure the protein expression of HSP70, hypoxia-inducible factor-1α (HIF-1α), endothelin-1 (ET-1), and inducible nitric oxide synthase (iNOS) in lung tissues. RESULTS: At 3, 7, 10, and 14 days after model establishment, the HPH model group and the empty virus group had a significantly higher mPAP than the blank control group ( P 0.05), but had significantly higher MA% and MT% than the blank control group ( P 0.05). CONCLUSIONS: In neonatal rats with HPH, HSP70 transfection can increase the expression of HSP70 in lung tissues, downregulate the expression of HIF-1α, ET-1, and iNOS, alleviate pulmonary vascular remodeling, and reduce pulmonary artery pressure; therefore, it may become a new strategy for the treatment of HPH in neonates.

Modern technologies not only provide a variety of communication modes, e.g., texting, cellphone conversation, and online instant messaging, but they also provide detailed electronic traces of these communications between individuals. These electronic traces indicate that the interactions occur in temporal bursts. Here, we study the inter-call durations of the 100,000 most-active cellphone users of a Chinese mobile phone operator. We confirm that the inter-call durations follow a power-law distribution with an exponential cutoff at the population level but find differences when focusing on individual users. We apply statistical tests at the individual level and find that the inter-call durations follow a power-law distribution for only 3460 individuals (3.46%). The inter-call durations for the majority (73.34%) follow a Weibull distribution. We quantify individual users using three measures: out-degree, percentage of outgoing calls, and communication diversity. We find that the cellphone users with a power-law duration distribution fall into three anomalous clusters: robot-based callers, telecom frauds, and telephone sales. This information is of interest to both academics and practitioners, mobile telecom operator in particular. In contrast, the individual users with a Weibull duration distribution form the fourth cluster of ordinary cellphone users. We also discover more information about the calling patterns of these four clusters, e.g., the probability that a user will call the $c_r$-th most contact and the probability distribution of burst sizes. Our findings may enable a more detailed analysis of the huge body of data contained in the logs of massive users., Comment: 7 pages and 8 figues

In China the video open courses along with the resource sharing courses constitute the open online courses. Evaluation of the open online course invariably is from education sector, calls "top-down" evaluation. In order to perfect the evaluation of the open online course, the paper describes a kind of "bottom-up” evaluation index system, evaluation is from learner. By using Delphi method, indexes and weights in system are established. Furthermore, the evaluation platform is developed according "bottom-up” open online course evaluation index system. Results of this research can help the open online course with obtaining more comprehensive evaluation.

Rationale: Epidural hematomas can develop following intrathecal puncture, spinal vascular malformation, or spontaneous hemorrhage. Prompt recognition of symptoms and referral to neurosurgical services are crucial for recovery. We report a rare case of delayed removal of an epidural hematoma that resulted in good patient outcomes. Patient concerns: A 69-year-old woman weighing 58 kg presented with back pain that had persisted for 12 years. Her medical history was notable for hypertension. Cervical computed tomography angiography indicated a giant abdominal aortic aneurysm measuring 11.58 × 17.34 × 13.00 cm in her abdominal cavity. Stent graft implantation was scheduled by the interventional therapy group to treat her abdominal aortic aneurysm under single-dose spinal anesthesia. Postoperatively, the patient complained of numbness and swelling of her lower extremities, with progressive paralysis developing in both legs accompanied with sensory disturbances. Diagnoses: Delayed magnetic resonance imaging detected an epidural hematoma. Interventions: Eighty hours after the onset of sensorimotor symptoms, lumbar decompression and removal of the hematoma were performed via laminectomy under general anesthesia. Outcomes: The patient was discharged 2 months after the operation with a 3/5 score on the Muscle Strength Grading System. Lessons: Laminectomy may be effective in achieving a good prognosis despite a considerable delay in diagnosis.

On the basis of a transform lemma, an asymptotic expansion of the bilinear finite element is derived over graded meshes for the Steklov eigenvalue problem, such that the Richardson extrapolation can be applied to increase the accuracy of the approximation, from which the approximation of O(h 3.5) is obtained. In addition, by means of the Rayleigh quotient acceleration technique and an interpolation postprocessing method, the superconvergence of the bilinear finite element is presented over graded meshes for the Steklov eigenvalue problem, and the approximation of O(h 3) is gained. Finally, numerical experiments are provided to demonstrate the theoretical results.

In this paper, we study the superconvergence of the frictionless Signorini problem. When approximated by bilinear finite elements, by virtue of the information on the contact zone, we can derive a superconvergence rate of O(h32) under a proper regularity assumption. Finally, a numerical test is given to verify our result.

Much empirical evidence shows that individuals usually exhibit significant homophily in social networks. We demonstrate, however, skill complementarity enhances heterophily in the formation of collaboration networks, where people prefer to forge social ties with people who have professions different from their own. We construct a model to quantify the heterophily by assuming that individuals choose collaborators to maximize utility. Using a huge database of online societies, we find evidence of heterophily in collaboration networks. The results of model calibration confirm the presence of heterophily. Both empirical analysis and model calibration show that the heterophilous feature is persistent along the evolution of online societies. Furthermore, the degree of skill complementarity is positively correlated with their production output. Our work sheds new light on the scientific research utility of virtual worlds for studying human behaviors in complex socioeconomic systems.

Clarification of the metabolic mechanisms underlying salt stress responses in plants will allow further optimization of crop breeding and cultivation to obtain high yields in saline-alkali land. Here, we characterized 68 differential metabolites of cultivated soybean (Glycine max) and wild soybean (Glycine soja) under neutral-salt and alkali-salt stresses using gas chromatography-mass spectrometry (GC-MS)-based metabolomics, to reveal the physiological and molecular differences in salt tolerance. According to comparisons of growth parameters under the two kinds of salt stresses, the level of inhibition in wild soybean was lower than in cultivated soybean, especially under alkali-salt stress. Moreover, wild soybean contained significantly higher amounts of phenylalanine, asparagine, citraconic acid, citramalic acid, citric acid and α-ketoglutaric acid under neutral-salt stress, and higher amounts of palmitic acid, lignoceric acid, glucose, citric acid and α-ketoglutaric acid under alkali-salt stress, than cultivated soybean. Further investigations demonstrated that the ability of wild soybean to salt tolerance was mainly based on the synthesis of organic and amino acids, and the more active tricarboxylic acid cycle under neutral-salt stress. In addition, the metabolite profiling analysis suggested that the energy generation from β-oxidation, glycolysis and the citric acid cycle plays important roles under alkali-salt stress. Our results extend the understanding of mechanisms involved in wild soybean salt tolerance and provide an important reference for increasing yields and developing salt-tolerant soybean cultivars.

The electronic structures and spectroscopic properties of the three tridentate cyclometalated Pt(II) complexes Pt(N/\N/\C)C(triple bond)CPh (N/\N/\CH = 6-phenyl-2,2'-bipyridine) (1), Pt(N/\N/\S)C(triple bond)CPh (N/\N/\SH = 6-thienyl-2,2'-bipyridine) (2), and Pt(N/\N/\O)C(triple bond)CPh (N/\N/\OH = 6-furyl-2,2'-bipyridine) (3) were investigated theoretically using the density functional theory (DFT) method. The geometric structures of the complexes in the ground and excited states were explored at the B3LYP and UB3LYP levels, respectively. The absorption and emission spectra of the complexes in CH2Cl2 and CH3CN solutions were calculated by time-dependent density functional theory (TD-DFT) with the PCM solvent model. The calculated energies of the lowest singlet state and lowest triplet state in the three complexes are in good agreement with the results of experimental absorption and luminescence studies. All of the lowest-lying transitions were categorized as LLCT combined with MLCT transitions. The 623-nm emission of 1 from the 3A' --1A' transition was assigned as 3LLCT and 3MLCT transitions, whereas the 657- and 681-nm emissions of 2 and 3, respectively, were attributed to 3ILCT perturbed by 3MLCT transitions. NLO response calculations revealed that the nonzero values of the static first hyperpolarizability (beta0) for 1-3 are greatly enhanced through the introduction of the metal Pt(II) into the cyclometalated ligands, an effect that is determined by MLCT and LLCT transitions.

People in modern societies form different social networks through numerous means of communication. These communication networks reflect different aspects of human's societal structure. The billing records of calls among mobile phone users enable us to construct a directed calling network (DCN) and its Bonferroni network (SVDCN) in which the preferential communications are statistically validated. Here we perform a comparative investigation of the cliques of the original DCN and its SVDCN constructed from the calling records of more than nine million individuals in Shanghai over a period of 110 days. We find that the statistical properties of the cliques of the two calling networks are qualitatively similar and the clique members in the DCN and the SVDCN exhibit idiosyncratic behaviors quantitatively. Members in large cliques are found to be spatially close to each other. Based on the clique degree profile of each mobile phone user, the most active users in the two calling networks can be classified in to several groups. The users in different groups are found to have different calling behaviors. Our study unveils interesting communication behaviors among mobile phone users that are densely connected to each other., 18 pages, 10 figures

Latent Dirichlet Allocation (LDA), has been recently used to automatically generate text corpora topics, and applied to sentences extraction based multi-document summarization algorithms. However, not all the estimated topics are of equal importance or correspond to genuine themes of the domain. Some of the topics can be a collection of irrelevant or background words, or represent insignificant themes. This paper proposed a topic-sensitive algorithm for multi-document summarization. Our approach is distinguished from existing approaches in that we use LDA model to identify and distinguish significance topic which is used in sentence weight calculation. Moreover, beside topic characteristics, this approach also considered some statistics characteristics, such as term frequency, sentence position, sentence length, etc. This approach not only highlights the advantages of statistics characteristics, but also cooperated with LDA topic model. The experiments showed that the proposed algorithm achieved better performance compared the other state-of-the-art algorithms on DUC2002 corpus.

Mobile phone calling is one of the most widely used communication methods in modern society. The records of calls among mobile phone users provide us a valuable proxy for the understanding of human communication patterns embedded in social networks. Mobile phone users call each other forming a directed calling network. If only reciprocal calls are considered, we obtain an undirected mutual calling network. The preferential communication behavior between two connected users can be statistically tested and it results in two Bonferroni networks with statistically validated edges. We perform a comparative analysis of the statistical properties of these four networks, which are constructed from the calling records of more than nine million individuals in Shanghai over a period of 110 days. We find that these networks share many common structural properties and also exhibit idiosyncratic features when compared with previously studied large mobile calling networks. The empirical findings provide us an intriguing picture of a representative large social network that might shed new lights on the modelling of large social networks.

In friendship networks, individuals have different numbers of friends, and the closeness or intimacy between an individual and her friends is heterogeneous. Using a statistical filtering method to identify relationships about who depends on whom, we construct dependence networks (which are directed) from weighted friendship networks of avatars in more than two hundred virtual societies of a massively multiplayer online role-playing game (MMORPG). We investigate the evolution of triadic motifs in dependence networks. Several metrics show that the virtual societies evolved through a transient stage in the first two to three weeks and reached a relatively stable stage. We find that the unidirectional loop motif (${\rm{M}}_9$) is underrepresented and does not appear, open motifs are also underrepresented, while other close motifs are overrepresented. We also find that, for most motifs, the overall level difference of the three avatars in the same motif is significantly lower than average, whereas the sum of ranks is only slightly larger than average. Our findings show that avatars' social status plays an important role in the formation of triadic motifs., Comment: 8 Latex pages + 5 figures

Traders adopt different trading strategies to maximize their returns in financial markets. These trading strategies not only results in specific topological structures in trading networks, which connect the traders with the pairwise buy-sell relationships, but also have potential impacts on market dynamics. Here, we present a detailed analysis on how the market behaviors are correlated with the structures of traders in trading networks based on audit trail data for the Baosteel stock and its warrant at the transaction level from 22 August 2005 to 23 August 2006. In our investigation, we divide each trade day into 48 time windows with a length of five minutes, construct a trading network within each window, and obtain a time series of over 1,100 trading networks. We find that there are strongly simultaneous correlations between the topological metrics (including network centralization, assortative index, and average path length) of trading networks that characterize the patterns of order execution and the financial variables (including return, volatility, intertrade duration, and trading volume) for the stock and its warrant. Our analysis may shed new lights on how the microscopic interactions between elements within complex system affect the system's performance., 3 tables and 5 pages

Concrete can be damaged under the effects of carbonation and the freeze-thaw cycle, which is a common cause of premature failure for concrete structures. In this study, range analysis was performed for compressive strength results after carbonation and freeze-thaw cycles for 90 days. A carbonation test, freeze-thaw test, and the alternating cycle of carbonation and freeze-thaws were performed to measure the relative dynamic elastic modulus and flexural strength of concrete samples. The results showed that specimens subjected to thawing first, then carbonation suffered the greatest impairment to strength due to expansion and osmotic pressures caused by water motion after thawing; this caused some of the original closed pores to link together, which loosened the internal organization and increased total porosity. The dynamic elastic modulus loss and weight loss of carbonized specimens were smaller than those of uncarbonized specimens within a reasonable range of carbonation. The flexural strength carbonation declined as the water-binder ratio or fly ash content increased.

Humans are heterogenous and the behaviors of individuals could be different from that at the population level. We conduct an in-depth study of the temporal patterns of cellphone conversation activities of 73'339 anonymous cellphone users with the same truncated Weibull distribution of inter-call durations. We find that the individual call events exhibit a pattern of bursts, in which high activity periods are alternated with low activity periods. Surprisingly, the number of events in high activity periods are found to conform to a power-law distribution at the population level, but follow an exponential distribution at the individual level, which is a hallmark of absence of memory in individual call activities. Such exponential distribution is also observed for the number of events in low activity periods. Together with the exponential distributions of inter-call durations within bursts and of the intervals between consecutive bursts, we demonstrate that the individual call activities are driven by two independent Poisson processes, which can be combined within a minimal model in terms of a two-state first-order Markov chain giving very good agreement with the empirical distributions using the parameters estimated from real data for about half of the individuals in our sample. By measuring directly the distributions of call rates across the population, which exhibit power-law tails, we explain the difference with previous population level studies, purporting the existence of power-law distributions, via the "Superposition of Distributions" mechanism: The superposition of many exponential distributions of activities with a power-law distribution of their characteristic scales leads to a power-law distribution of the activities at the population level., 16 pages, 7 figures

Retroviral gene transfer into human myeloid precursor cells allows introduction of marker genes as well as genes conferring resistance to chemotherapeutic drugs. We transduced a human mutant dihydrofolate reductase (DHFR) cDNA into CD34 antigen-positive peripheral blood cells from patients with breast or ovarian cancer obtained after treatment with chemotherapy and granulocyte colony-stimulating factor (G-CSF). This mutant DHFR has been shown to confer resistance to methotrexate (MTX) in murine bone marrow. We established a transduction protocol that permitted ex vivo expansion and selection of transduced early progenitor cells. The number of progenitor cells from transduced CD34- positive cells increased 50-fold after cytokine prestimulation with interleukin-1 (IL-1), c-kit ligand (KL; stem cell factor), and IL-3 and 2 weeks in liquid culture. Transduced colony-forming unit-granulocyte- macrophage (CFU-GM), assayed directly after the transduction procedure, were protected completely against 2 x 10(-8) mol/L MTX, a concentration that significantly reduced the CFU-GM detected in the control population. Gene transfer of the mutant DHFR led to a twofold selective advantage for a pre-CFU population after exposure to MTX in liquid culture (P < .001). Polybrene, in contrast with protamine, significantly inhibited the expansion of progenitors. The presence of proviral DNA was monitored by polymerase chain reaction (PCR) and was detected in greater than 80% of CFU-GM and ex vivo expanded pre-CFU. We have demonstrated that human hematopoietic precursor cells can be expanded extensively after retroviral gene transfer. The same population of early progenitors can be selected ex vivo with low-dose MTX. As long-term expression of transduced genes in human hematopoietic cells remains a problem in vivo, these results may have implications for future clinical trials, especially for the introduction of nonselectable genes.

Loss of carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) expression is an adverse prognostic factor in hepatocellular carcinoma (HCC). The purpose of this study was to investigate the expression of CEACAM1 and its effect on relapse-free survival (RFS) following liver transplantation (LT) for HCC.Expression of CEACAM1 was immunohistochemically detected in HCC specimens from 48 patients. The relationship between CEACAM1 expression and clinicopathologic variables, as well as tumor recurrence, was further analyzed.Of the 48 HCC specimens, membranous CEACAM1 expression was detected in 25 specimens and cytoplasmic CEACAM1 expression was detected in 19 specimens. Four specimens had loss of CEACAM1 expression. Loss of membranous CEACAM1 expression was significantly associated with tumor size, tumor number, and serum α-fetoprotein levels (all P0.05). Patients with loss of membranous CEACAM1 had significantly poorer RFS than patients with membranous expression, determined via Kaplan-Meier analysis (P = 0.027). Multivariate analysis revealed that loss of membranous CEACAM1 expression might be an independent prognostic factor of RFS for HCC patients after liver transplantation (P = 0.037).Loss of membranous CEACAM1 expression in HCC was closely associated with aggressive tumor biology and might be a relapsing biomarker of HCC treated with LT.

Bariatric surgery offers successful resolution of type 2 diabetes mellitus (T2DM). However, recurrence of T2DM has been observed in a number of patients with initial resolution after bariatric surgery. This study aimed to induce reversal of the improvement of diabetes in T2DM rats after duodenal-jejunal bypass (DJB), and identify the effects of weight changes and gut hormones that might be involved.DJB surgery was performed in two T2DM rat models (n=20 for each group): non-obese Goto-Kakizaki (GK) rats, and moderately-obese T2DM rats induced by a combination of a high-fat diet (HFD) and low-dose streptozotocin (HS rats). The controls were sham-operated and non-treated rats. All rats were then randomly divided into HFD- and low-fat diet (LFD)-fed groups. Glucose tolerance, insulin tolerance, glucose-stimulated insulin, glucagon-like peptide-1 (GLP-1) and peptide YY (PYY) secretion, food intake and body weight were measured and compared with controls.DJB surgery resulted in a significant improvement in glucose tolerance in both GK and HS rats fed with either HFD or LFD. In contrast to LFD-fed rats, improved glucose tolerance was impaired in GK and HS rats fed with an HFD, accompanied by re-impairment of insulin tolerance and failure in enhancement of insulin secretion. There was no significant difference in food intake and body weight between DJB-operated and control rats, and between HFD- and LFD-fed rats. Glucose-stimulated GLP-1 and PYY levels were significantly increased after DJB surgery; however, they were not significantly different between HFD- and LFD-fed rats.An HFD reverses the improvement in glucose tolerance induced by DJB surgery in T2DM rats, primarily ascribing to the re-impairment of insulin sensitivity, but does not change body weight, GLP-1 and PYY levels.

Chinese hamster ovary (CHO) DHFR − cells were converted into the DHFR + phenotype when they were transfected with a mammalian expression vector carrying human dihydrofolate reductase-encoding cDNAs ( DHFR ) containing a Ser 31 or a Ser 34 mutation. Furthermore, transfection of these mutants into wild-type CHO cells resulted in resistance to high levels of methotrexate (MTX), indicating that these human variants can act as dominant selectable markers. Southern blot analysis and polymerase chain reaction amplifications confirmed that the transfected plasmids were integrated into the CHO DNA. Gene copy number analysis revealed that both the Ser 31 and the Ser 34 mutants are amplifiable when grown in increasing concentrations of MTX. Retrovirus-mediated gene transfer of the Ser 31 mutant into mouse marrow progenitor cells also resulted in MTX-resistant CFU-GM (colony-forming unit-granulocyte macrophage) cells.

In the title compound, C14H17N2O4P·CH3OH, the planes of the pyridinium-2-ylamino and 2-hydroxyphenyl groups form a dihedral angle of 75.6 (1)°, with the pyridinium NH group and the 2-hydroxyphenyl OH group pointing in opposite directions. Three intramolecular hydrogen bonds are observed. Two phosphonate and two methanol molecules are connected by O—H...O hydrogen bonds as a centrosymmetric dimeric cluster, and interact further with other dimeric clusters via N—H...O, O—H...O and C—H...O hydrogen bonds and C—H...π interactions, resulting in a sheet structure.

Summary The enzyme 5.1O-methenyltetrahydrofolate synthetase catalyzes the key enzymatic reaction in the pathway by which 5-formyl tetrahydrofolate (leucovorin) enters the folate coenzyme pool. The distribution of this enzyme in different organs and tumor cell lines was studied. This enzyme has a wide distribution among organs and tumor cell lines with highest levels of activity in liver and kidney. Tumor cell lines also contain significant levels of this enzyme activity. Thus, leucovorin can be converted to active folate coenzyme forms in organs and tumor cells, and does not require conversion in liver alone. The implications of these findings for leucovorin usage as "rescue" after methotrexate treatment or to augment fluoropyrimidine cytotoxicity are discussed.