186 research outputs found

    Multiple superconducting gap and anisotropic spin fluctuations in iron arsenides: Comparison with nickel analog

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    We present extensive 75As NMR and NQR data on the superconducting arsenides PrFeAs0.89F0.11 (Tc=45 K), LaFeAsO0.92F0.08 (Tc=27 K), LiFeAs (Tc = 17 K) and Ba0.72K0.28Fe2As2 (Tc = 31.5 K) single crystal, and compare with the nickel analog LaNiAsO0.9F0.1 (Tc=4.0 K) . In contrast to LaNiAsO0.9F0.1 where the superconducting gap is shown to be isotropic, the spin lattice relaxation rate 1/T1 in the Fe-arsenides decreases below Tc with no coherence peak and shows a step-wise variation at low temperatures. The Knight shift decreases below Tc and shows a step-wise T variation as well. These results indicate spinsinglet superconductivity with multiple gaps in the Fe-arsenides. The Fe antiferromagnetic spin fluctuations are anisotropic and weaker compared to underdoped copper-oxides or cobalt-oxide superconductors, while there is no significant electron correlations in LaNiAsO0.9F0.1. We will discuss the implications of these results and highlight the importance of the Fermi surface topology.Comment: 6 pages, 11 figure

    Identification of optimum scopes of environmental factors for snails using spatial analysis techniques in Dongting Lake Region, China

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    BACKGROUND: Owing to the harmfulness and seriousness of Schistosomiasis japonica in China, the control and prevention of S. japonica transmission are imperative. As the unique intermediate host of this disease, Oncomelania hupensis plays an important role in the transmission. It has been reported that the snail population in Qiangliang Lake district, Dongting Lake Region has been naturally declining and is slowly becoming extinct. Considering the changes of environmental factors that may cause this phenomenon, we try to explore the relationship between circumstance elements and snails, and then search for the possible optimum scopes of environmental factors for snails. METHODS: Moisture content of soil, pH, temperature of soil and elevation were collected by corresponding apparatus in the study sites. The LISA statistic and GWR model were used to analyze the association between factors and mean snail density, and the values in high-high clustered areas and low-low clustered areas were extracted to find out the possible optimum ranges of these elements for snails. RESULTS: A total of 8,589 snail specimens were collected from 397 sampling sites in the study field. Besides the mean snail density, three environmental factors including water content, pH and temperature had high spatial autocorrelation. The spatial clustering suggested that the possible optimum scopes of moisture content, pH, temperature of the soil and elevation were 58.70 to 68.93%, 6.80 to 7.80, 22.73 to 24.23°C and 23.50 to 25.97 m, respectively. Moreover, the GWR model showed that the possible optimum ranges of these four factors were 36.58 to 61.08%, 6.541 to 6.89, 24.30 to 25.70°C and 23.50 to 29.44 m, respectively. CONCLUSION: The results indicated the association between snails and environmental factors was not linear but U-shaped. Considering the results of two analysis methods, the possible optimum scopes of moisture content, pH, temperature of the soil and elevation were 58.70% to 68.93%, 6.6 to 7.0, 22.73°C to 24.23°C, and 23.5 m to 26.0 m, respectively. The findings in this research will help in making an effective strategy to control snails and provide a method to analyze other factors

    Impurity-induced in-gap state and Tc in sign-reversing s-wave superconductors: analysis of iron oxypnictide superconductors

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    The sign-reversing fully gapped superconducting state, which is expected to be realized in oxypnictide superconductors, can be prominently affected by nonmagnetic impurities due to the interband scattering of Cooper pairs. We study this problem based on the isotropic two-band BCS model: In oxypnictide superconductors, the interband impurity scattering II' is not equal to the intraband one II. In the Born scattering regime, the reduction in Tc is sizable and the impurity-induced density of states (DOS) is prominent if III\sim I', due to the interband scattering. Although impurity-induced DOS can yield a power-law temperature dependence in 1/T11/T_1, a sizable suppression in Tc is inevitably accompanied. In the unitary scattering regime, in contrast, impurity effect is very small for both Tc and DOS except at I=II=I'. By comparing theory and experiments, we expect that the degree of anisotropy in the s±s_\pm-wave gap function strongly depends on compounds.Comment: 16 pages, 5 figures, to be published in New. J. Phy

    Expression of the phosphorylated MEK5 protein is associated with TNM staging of colorectal cancer

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    <p>Abstract</p> <p>Background</p> <p>Activation of MEK5 in many cancers is associated with carcinogenesis through aberrant cell proliferation. In this study, we determined the level of phosphorylated MEK5 (pMEK5) expression in human colorectal cancer (CRC) tissues and correlated it with clinicopathologic data.</p> <p>Methods</p> <p>pMEK5 expression was examined by immunohistochemistry in a tissue microarray (TMA) containing 335 clinicopathologic characterized CRC cases and 80 cases of nontumor colorectal tissues. pMEK5 expression of 19 cases of primary CRC lesions and paired with normal mucosa was examined by Western blotting. The relationship between pMEK5 expression in CRC and clinicopathologic parameters, and the association of pMEK5 expression with CRC survival were analyzed respectively.</p> <p>Results</p> <p>pMEK5 expression was significantly higher in CRC tissues (185 out of 335, 55.2%) than in normal tissues (6 out of 80, 7.5%; <it>P </it>< 0.001). Western blotting demonstrated that pMEK5 expression was upregulated in 12 of 19 CRC tissues (62.1%) compared to the corresponding adjacent nontumor colorectal tissues. Overexpression of pMEK5 in CRC tissues was significantly correlated to the depth of invasion (<it>P </it>= 0.001), lymph node metastasis (<it>P </it>< 0.001), distant metastasis (<it>P </it>< 0.001) and high preoperative CEA level (<it>P </it>< 0.001). Consistently, the pMEK5 level in CRC tissues was increased following stage progression of the disease (<it>P </it>< 0.001). Analysis of the survival curves showed a significantly worse 5-year disease-free (<it>P </it>= 0.002) and 5-year overall survival rate (<it>P </it>< 0.001) for patients whose tumors overexpressed pMEK5. However, in multivariate analysis, pMEK5 was not an independent prognostic factor for CRC (DFS: <it>P </it>= 0.139; OS: <it>P </it>= 0.071).</p> <p>Conclusions</p> <p>pMEK5 expression is correlated with the staging of CRC and its expression might be helpful to the TNM staging system of CRC.</p

    Ethical leadership as antecedent of job satisfaction, affective organizational commitment and intention to stay among volunteers of non-profit organizations

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    The aim of this paper is to investigate among a group of non-profit organizations: (a) the effect of ethical leadership (EL) on volunteers\u2019 satisfaction, affective organizational commitment and intention to stay in the same organization; (b) the role played by job satisfaction as a mediator in the relationship between EL and volunteers\u2019 intentions to stay in the same organization, as well as between EL and affective commitment. An anonymous questionnaire was individually administered to 198 Italian volunteers of different non-profit organizations. The questionnaire contained the Ethical Leadership Scale, the Volunteers Satisfaction Index, the Affective organization Scale, as well as questions regarding the participants\u2019 age, sex, type of work, level of education, length of their volunteer works, intention to volunteer in the following months in the same organization. The construct as well the effects of EL on volunteers is approached in light of the Social Exchange Theory and the Social Learning Theory. Structural equation models were used to test hypothesized relationships. The results confirm the role of mediation of volunteer satisfaction in the relationships between the variables studied. In particular, EL was found to be positively associated both with volunteers\u2019 intention of staying and with their affective commitment. In the first case this relationship is fully explained by the mediation of the volunteers\u2019 satisfaction, while the latter is explained by both direct and indirect factors. To the authors\u2019 knowledge, this the first attempt to understand the role played by EL on volunteers\u2019 behavior and, more in general, in the management of non-profit organizations. Findings are relevant both for practitioners and managers of non-profit organization, since they suggest the relevance of the perception of EL by volunteers, as well as for scholars, since they further deepen the knowledge on EL and its effects on the followers. Limits of the study: the questionnaire was administered only among a group of non-statistical sample of volunteers. Furthermore, the study reached only volunteers from Italian non-profit organization

    The IPIN 2019 Indoor Localisation Competition—Description and Results

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    IPIN 2019 Competition, sixth in a series of IPIN competitions, was held at the CNR Research Area of Pisa (IT), integrated into the program of the IPIN 2019 Conference. It included two on-site real-time Tracks and three off-site Tracks. The four Tracks presented in this paper were set in the same environment, made of two buildings close together for a total usable area of 1000 m 2 outdoors and and 6000 m 2 indoors over three floors, with a total path length exceeding 500 m. IPIN competitions, based on the EvAAL framework, have aimed at comparing the accuracy performance of personal positioning systems in fair and realistic conditions: past editions of the competition were carried in big conference settings, university campuses and a shopping mall. Positioning accuracy is computed while the person carrying the system under test walks at normal walking speed, uses lifts and goes up and down stairs or briefly stops at given points. Results presented here are a showcase of state-of-the-art systems tested side by side in real-world settings as part of the on-site real-time competition Tracks. Results for off-site Tracks allow a detailed and reproducible comparison of the most recent positioning and tracking algorithms in the same environment as the on-site Tracks

    Mesenchymal stem/stromal cells as a delivery platform in cell and gene therapies

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    Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease

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    Background: Experimental and clinical data suggest that reducing inflammation without affecting lipid levels may reduce the risk of cardiovascular disease. Yet, the inflammatory hypothesis of atherothrombosis has remained unproved. Methods: We conducted a randomized, double-blind trial of canakinumab, a therapeutic monoclonal antibody targeting interleukin-1β, involving 10,061 patients with previous myocardial infarction and a high-sensitivity C-reactive protein level of 2 mg or more per liter. The trial compared three doses of canakinumab (50 mg, 150 mg, and 300 mg, administered subcutaneously every 3 months) with placebo. The primary efficacy end point was nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death. RESULTS: At 48 months, the median reduction from baseline in the high-sensitivity C-reactive protein level was 26 percentage points greater in the group that received the 50-mg dose of canakinumab, 37 percentage points greater in the 150-mg group, and 41 percentage points greater in the 300-mg group than in the placebo group. Canakinumab did not reduce lipid levels from baseline. At a median follow-up of 3.7 years, the incidence rate for the primary end point was 4.50 events per 100 person-years in the placebo group, 4.11 events per 100 person-years in the 50-mg group, 3.86 events per 100 person-years in the 150-mg group, and 3.90 events per 100 person-years in the 300-mg group. The hazard ratios as compared with placebo were as follows: in the 50-mg group, 0.93 (95% confidence interval [CI], 0.80 to 1.07; P = 0.30); in the 150-mg group, 0.85 (95% CI, 0.74 to 0.98; P = 0.021); and in the 300-mg group, 0.86 (95% CI, 0.75 to 0.99; P = 0.031). The 150-mg dose, but not the other doses, met the prespecified multiplicity-adjusted threshold for statistical significance for the primary end point and the secondary end point that additionally included hospitalization for unstable angina that led to urgent revascularization (hazard ratio vs. placebo, 0.83; 95% CI, 0.73 to 0.95; P = 0.005). Canakinumab was associated with a higher incidence of fatal infection than was placebo. There was no significant difference in all-cause mortality (hazard ratio for all canakinumab doses vs. placebo, 0.94; 95% CI, 0.83 to 1.06; P = 0.31). Conclusions: Antiinflammatory therapy targeting the interleukin-1β innate immunity pathway with canakinumab at a dose of 150 mg every 3 months led to a significantly lower rate of recurrent cardiovascular events than placebo, independent of lipid-level lowering. (Funded by Novartis; CANTOS ClinicalTrials.gov number, NCT01327846.

    Pure and multi metal oxide nanoparticles: synthesis, antibacterial and cytotoxic properties

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