4,047 research outputs found
Enhanced Orbital Degeneracy in Momentum Space for LaOFeAs
The Fermi surfaces (FS) of LaOFeAs (in =0 plane) consist of two
hole-type circles around point, which do not touch each other, and two
electron-type co-centered ellipses around M point, which are degenerate along
the M-X line. By first-principles calculations, here we show that additional
degeneracy exists for the two electron-type FS, and the crucial role of
F-doping and pressure is to enhance this orbital degeneracy. It is suggested
that the inter-orbital fluctuation is the key point to understand the
unconventional superconductivity in these materials.Comment: 4 pages, 5 figure
User Interests Modeling Based on Multi-source Personal Information Fusion and Semantic Reasoning
Abstract. User interests are usually distributed in different systems on the Web. Traditional user interest modeling methods are not designed for integrating and analyzing interests from multiple sources, hence, they are not very effective for obtaining comparatively complete description of user interests in the distributed environment. In addition, previous studies concentrate on the text level analysis of user interests, while semantic relationships among interests are not fully investigated. This might cause incomplete and incorrect understanding of the discovered interests, especially when interests are from multiple sources. In this paper, we propose an approach of user interest modeling based on multi-source personal information fusion and semantic reasoning. We give different fusion strategies for interest data from multiple sources. Further more, we investigate the semantic relationship between users' explicit interests and implicit interests by reasoning through concept granularity. Semantic relatedness among interests are also briefly illustrated for information fusion. Illustrative examples based on multiple sources on the Web (e.g. microblog system Twitter, social network sites Facebook and LinkedIn, personal homepage, etc.) show that proposed approach is potentially effective
Rotective effect of Fengliao-Changweikang extracts, a traditional Chinese herbal medicine formula,on mucosa in rat with chronic gastritis
Background: Fengliao-Changwei-Kang(FCK), the Chinese patent drug, is a famous traditional Chinese herbal medicine formula. It has a significant effect on the clinic treatment of gastrointestinal diseases including gastritis, enteritis and diarrhea for many years. However, there is few research on the protective effects of FCK on the gastric mucosa of chronic gastritis (CG) model rat. Objective: The present study aimed to explore the effects of FCK extract on mucosa in rats with Chronic Gastritis.Materials and Methods: 50 SD mice were randomly divided into 5 groups with 10 in each group(five per sex). The groups are respectively control group, model group, low, middle and high FCK extracts (FCK I, II and III) group. The CG rat model was induced by synthetic methods. FCK I, II and III group were administrated with FCK extracts at 2.16g• kg, 4.32g• kg, 8.94g• kg once per day for 21 consecutive days, and the control group and model group were administrated the same volume of distilled water at 10mL/kg once per day. 16 hours after the last administration, the rats were anesthetized and their blood and stomach were drawn from vena cava and abdominal cavity. The serum levels of EGF was measured by enzyme linked immunosorbent assay(ELISA) method, the expression of growth factor receptor (EGFR) in gastric mucosa was detected by immunohistochemical method, and the mRNA expressions of NF-κB p65 was detected in-situ hybridization.Results: The inflammation grades and the expressions of NF-κB p65 mRNA in gastric mucosa of the model group were markedly higher than those of the control group (P<0.05). The inflammation grades of gastric mucosa and the expressions of NF-κB p65 mRNA in gastric mucosa the FCK extract group are significantly lower than those of the model group, and the FCK extract group at 8.64g/kg could greatly increase the serum levels of EGF and the expressions of EGFR in gastric mucosa. High EGF level was found in FCK extract group at 4.32g/kg, but low in FCK extract groups at 2.16g/kg. There were no marked differences among the rats from control group, model group and FCK extract group on ratio of Ll/L2 (P>0.05).Conclusions: FCK extract could alleviate mucosal inflammation by down regulating the expressions of NF-κB p65 mRNA and promote tissue repair by up regulating EGFR expression in gastric mucosa cell.Keywords: chronic gastritis; fengliao-changwei-kang extract; epidermal growth factor receptor; nuclear factor kappa B
Simple approach to highly oriented ZnO nanowire arrays: large-scale growth, photoluminescence and photocatalytic properties
Risk factors on healthcare-associated infections among tuberculosis hospitalized patients in China from 2001 to 2020: A systematic review and meta-analysis
Background: China has been still suffering from high burden attributable to tuberculosis (TB) and healthcare-associated infections (HAIs). TB patients are at high risk to get HAIs. Evidence-based guidelines or regulations to constrain the rising HAIs among TB hospitalized patients are needed in China. The aim of this systematic review and meta-analysis is to investigate the risk factors associated with HAIs among TB hospitalized patients in Chinese hospitals. Methods: Medline, EMBASE and Chinese Journals Online databases were searched. The search was limited to studies published from January 1st 2001 to December 31st 2020. Meta-analyses of ORs of the risk factors between patients with HAIs and patients without HAIs among TB hospitalized patients were estimated. Heterogeneity among studies was assessed based on the τ ^ 2 and I2 statistics to select the meta-analysis model. Review Manager 5.3 was employed and P < 0.05 was considered as statistical significance. Results: 851 records were filtered from the databases, of which 11 studies were included in the quantitative meta-analysis. A total of 11,922TB patients were included in the systematic review and meta-analysis, of which 1133 were diagnosed as having HAIs. Age older than 60 years (OR: 2.89 [2.01–4.15]), complications (OR: 3.28 [2.10–5.13]), diabetes mellitus (OR: 1.63 [1.22–2.19]), invasive procedure (OR: 3.80 [2.25–6.42]), longer than 15 hospitalization days (OR: 2.09 [1.64–2.64]), secondary tuberculosis (OR: 2.25 [1.48–3.42]), smoking (OR: 1.40[1.02–1.93]), underlying disease (OR: 2.66 [1.53–4.62]), and use of antibiotics (OR: 2.77 [2.35–3.27]) were the main risk factors associated with HAIs among TB hospitalized patients with a statistical significance (P < 0.05). Conclusions: Age older than 60 years, presence of complications, presence of diabetes mellitus, invasive procedure, longer than 15 hospitalization days, secondary tuberculosis, smoking, presence of underlying disease, and use of antibiotics were the main risk factors which had a negative impact on HAIs among TB hospitalized patients in Chinese hospitals. These findings provided evidence for policy makers and hospital managers to make effective infection prevention and control measures to constrain the rising HAIs. It is also required that more cost-effective infection prevention and control measures should be widely applied in routinely medical treatment and clinical management to reduce the occurrence of HAIs among TB hospitalized patients
Experimental and numerical studies of six small-scale continuous concrete slabs subjected to travelling fires
Graphene-Based Nanostructures in Electrocatalytic Oxygen Reduction
Application of graphene-type materials in electrocatalysis is a topic of
growing scientific and technological interest. A tremendous amount of research
has been carried out in the field of oxygen electroreduction, particularly with
respect to potential applications in the fuel cell research also with use of
graphene-type catalytic components. This work addresses fundamental aspects and
potential applications of graphene structures in the oxygen reduction
electrocatalysis. Special attention will be paid to creation of catalytically
active sites by using non-metallic heteroatoms as dopants, formation of
hierarchical nanostructured electrocatalysts, their long-term stability, and
application as supports for dispersed metals (activating interactions)
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