140 research outputs found
Superconductivity at 32K and anisotropy in Tl0.58Rb0.42Fe1.72Se2 crystals
Single crystals of Tl0.58Rb0.42Fe1.72Se2 are successfully grown with the
superconducting transition temperatures Tconset=32K and Tczero=31.4K. The Hall
coefficient exhibits a multi-band behavior, which is very similar to that of
all other Fe-based superconductors. We found that the susceptibility at the
normal state decreases with decreasing the temperature, indicating a strong
antiferromagnetic (AFM) spin fluctuation at the normal state, which might be
related to the superconductivity (SC). We also determined the upper critical
fields in ab-plane and along c-axis. The anisotropy of the superconductivity
determined by the ratio of Hc2ab and Hc2c is estimated to 5.0, which is larger
than that in (Ba,K)Fe2As2 and BaFe2-xCoxAs2, but smaller than that in cuprate
superconductors.Comment: 4 pages, 4 figure
Effects of the stem extracts of Schisandra glaucescens Diels on collagen-induced arthritis in Balb/c mice
Ethnopharmacological relevance
Schisandra glaucescens Diels (SGD) is used in a subclass of traditional Chinese medicine known as âTujia drugsâ. It has been long used for the treatment of rheumatoid arthritis (RA), cough with dyspnea, spontaneous sweating, night sweating, chronic diarrhea, and neurasthenia. As a woody liana growing in mountain jungles at the altitudes of 750â1800 m, it is mainly distributed in Sichuan and Hubei Provinces of China.
Aim of the study
To evaluate the antiarthritic activity of acetate (EA) and n-butanol (Bu) fractions of SGD extract on a collagen-induced arthritis mice model.
Materials and methods
Acute toxicity of EA and Bu fractions of SGD extract was evaluated by gavage on normal mice. Pharmacological investigations were conducted on arthritis male Balb/c mice. The animal model was induced by immunization with type II bovine collagen (CII) on the 1st and the 14th day of the experimental schedule. EA fraction (104, 312, 936 mg/kg), Bu fraction (156, 469, 1407 mg/kg) of SGD extract was orally administered every two days since the 15th day for 3 weeks. Progression of edema in the paws was measured using a vernier caliper every 3 days since the 10th day. At the end of the experiment, the spleen index and histological changes of the hind knee joints were investigated. Additionally, to explore the possible antirheumatic mechanisms of the EA and Bu fractions, ELISA was carried out to analyze TNF-α, IL-10, IL-6 and IL-1ÎČ in the serum.
Results
The half lethal doses of both EA and Bu fractions were much higher than the dose administered in the pharmacological investigations. Oral administration of EA fraction and Bu fraction of SGD extract significantly and does-dependently inhibited type ĐĐ collagen induced arthritis (CIA) in mice, as indicated by the effects on paws swelling and spleen index. Histopathological examinations demonstrated that SGD effectively protected the bones and cartilages of knee joints from erosion, lesion and deformation. Besides, the serum concentrations of cytokines TNF-α, IL-1ÎČ and IL-6 were significantly lower than the ones from the vehicle control group. Respectively, while cytokine IL-10 was remarkably higher compare with the vehicle control group.
Conclusions
SGD might be a safe and effective candidate for the treatment of RA, and deserves further investigation on the chemical components in both EA and Bu fractions of SGD extract
Salidroside Stimulates Mitochondrial Biogenesis and Protects against H 2
Salidroside (SAL) is an active component of Rhodiola rosea with documented antioxidative properties. The purpose of this study is to explore the mechanism of the protective effect of SAL on hydrogen peroxide- (H2O2-) induced endothelial dysfunction. Pretreatment of the human umbilical vein endothelial cells (HUVECs) with SAL significantly reduced the cytotoxicity brought by H2O2. Functional studies on the rat aortas found that SAL rescued the endothelium-dependent relaxation and reduced superoxide anion (O2â-) production induced by H2O2. Meanwhile, SAL pretreatment inhibited H2O2-induced nitric oxide (NO) production. The underlying mechanisms involve the inhibition of H2O2-induced activation of endothelial nitric oxide synthase (eNOS), adenosine monophosphate-activated protein kinase (AMPK), and Akt, as well as the redox sensitive transcription factor, NF-kappa B (NF-ÎșB). SAL also increased mitochondrial mass and upregulated the mitochondrial biogenesis factors, peroxisome proliferator-activated receptor gamma-coactivator-1alpha (PGC-1α), and mitochondrial transcription factor A (TFAM) in the endothelial cells. H2O2-induced mitochondrial dysfunction, as demonstrated by reduced mitochondrial membrane potential (ÎÏm) and ATP production, was rescued by SAL pretreatment. Taken together, these findings implicate that SAL could protect endothelium against H2O2-induced injury via promoting mitochondrial biogenesis and function, thus preventing the overactivation of oxidative stress-related downstream signaling pathways
Preparing for the Speaking Tasks of the <i>TOEFL iBT</i>Âź Test:An Investigation of the Journeys of Chinese Test Takers
Phytosterol content and the campesterol:sitosterol ratio influence cotton fiber development: role of phytosterols in cell elongation
An expanded evaluation of protein function prediction methods shows an improvement in accuracy
Background: A major bottleneck in our understanding of the molecular underpinnings of life is the assignment of function to proteins. While molecular experiments provide the most reliable annotation of proteins, their relatively low throughput and restricted purview have led to an increasing role for computational function prediction. However, assessing methods for protein function prediction and tracking progress in the field remain challenging. Results: We conducted the second critical assessment of functional annotation (CAFA), a timed challenge to assess computational methods that automatically assign protein function. We evaluated 126 methods from 56 research groups for their ability to predict biological functions using Gene Ontology and gene-disease associations using Human Phenotype Ontology on a set of 3681 proteins from 18 species. CAFA2 featured expanded analysis compared with CAFA1, with regards to data set size, variety, and assessment metrics. To review progress in the field, the analysis compared the best methods from CAFA1 to those of CAFA2. Conclusions: The top-performing methods in CAFA2 outperformed those from CAFA1. This increased accuracy can be attributed to a combination of the growing number of experimental annotations and improved methods for function prediction. The assessment also revealed that the definition of top-performing algorithms is ontology specific, that different performance metrics can be used to probe the nature of accurate predictions, and the relative diversity of predictions in the biological process and human phenotype ontologies. While there was methodological improvement between CAFA1 and CAFA2, the interpretation of results and usefulness of individual methods remain context-dependent. Keywords: Protein function prediction, Disease gene prioritizationpublishedVersio
An Expanded Evaluation of Protein Function Prediction Methods Shows an Improvement In Accuracy
Background: A major bottleneck in our understanding of the molecular underpinnings of life is the assignment of function to proteins. While molecular experiments provide the most reliable annotation of proteins, their relatively low throughput and restricted purview have led to an increasing role for computational function prediction. However, assessing methods for protein function prediction and tracking progress in the field remain challenging.
Results: We conducted the second critical assessment of functional annotation (CAFA), a timed challenge to assess computational methods that automatically assign protein function. We evaluated 126 methods from 56 research groups for their ability to predict biological functions using Gene Ontology and gene-disease associations using Human Phenotype Ontology on a set of 3681 proteins from 18 species. CAFA2 featured expanded analysis compared with CAFA1, with regards to data set size, variety, and assessment metrics. To review progress in the field, the analysis compared the best methods from CAFA1 to those of CAFA2.
Conclusions: The top-performing methods in CAFA2 outperformed those from CAFA1. This increased accuracy can be attributed to a combination of the growing number of experimental annotations and improved methods for function prediction. The assessment also revealed that the definition of top-performing algorithms is ontology specific, that different performance metrics can be used to probe the nature of accurate predictions, and the relative diversity of predictions in the biological process and human phenotype ontologies. While there was methodological improvement between CAFA1 and CAFA2, the interpretation of results and usefulness of individual methods remain context-dependent
An expanded evaluation of protein function prediction methods shows an improvement in accuracy
Background: A major bottleneck in our understanding of the molecular underpinnings of life is the assignment of function to proteins. While molecular experiments provide the most reliable annotation of proteins, their relatively low throughput and restricted purview have led to an increasing role for computational function prediction. However, assessing methods for protein function prediction and tracking progress in the field remain challenging.Results: We conducted the second critical assessment of functional annotation (CAFA), a timed challenge to assess computational methods that automatically assign protein function. We evaluated 126 methods from 56 research groups for their ability to predict biological functions using Gene Ontology and gene-disease associations using Human Phenotype Ontology on a set of 3681 proteins from 18 species. CAFA2 featured expanded analysis compared with CAFA1, with regards to data set size, variety, and assessment metrics. To review progress in the field, the analysis compared the best methods from CAFA1 to those of CAFA2.Conclusions: The top-performing methods in CAFA2 outperformed those from CAFA1. This increased accuracy can be attributed to a combination of the growing number of experimental annotations and improved methods for function prediction. The assessment also revealed that the definition of top-performing algorithms is ontology specific, that different performance metrics can be used to probe the nature of accurate predictions, and the relative diversity of predictions in the biological process and human phenotype ontologies. While there was methodological improvement between CAFA1 and CAFA2, the interpretation of results and usefulness of individual methods remain context-dependent
Persuasion Knowledge and Consumers' Attitudes towards Benefit-Based Advertising
Persuasion knowledge and its impact on advertising responses have been widely studied in the field of advertising to children. Little research attention, however, has been paid into the influence of persuasion knowledge among adult consumers. This paper examines the relationship between two key persuasion knowledge constructs, namely information intent and persuasive intent, and adult consumersâ responses to benefit-based advertising. Results showed that significant relationships exit between the informative intent and consumersâattitudes towards both functional and experiential benefit advertising, but not symbolic benefit advertising. No significant relationship, however, has been detected between the persuasive intent and consumersâ attitudes towards any benefit based advertising. The paper closes with academic and applied implications for higher education advertisers
Is Chinaâs Urbanization Quality and Ecosystem Health Developing Harmoniously? An Empirical Analysis from Jiangsu, China
The relationship between urbanization and ecology environment is a current research hotspot. Most literature to date focuses on the interaction between urbanization and a single component of the ecosystem (e.g., water, forests, and ecosystem services), while little attention has been given to the relationship between urbanization quality and ecosystem health. Accordingly, this paper used the entropy method and vigorâorganizationâresilience model to measure the urbanization quality and ecosystem health in Jiangsu Province. Based on the results, this paper analyzed the spatial-temporal pattern and evolution characteristics of the coordination degree between urbanization quality and ecosystem health in Jiangsu Province in 2000, 2005, 2010, 2015, and 2017 and then used the geographic detector and Tobit regression model to explore its internal driving forces and external influencing factors. The results show the following: 1. The changing trend of urbanization quality and ecosystem health in the Jiangsu Province share some traits; it first descends and then ascends; 2. The cities in Jiangsu Province are all between primary coordination and high-quality coordination. Central Jiangsu has the best coupling coordination degree, and Northern Jiangsu has the worst coupling coordination degree, but the overall coordination degree is on the rise; 3. The internal and external factors that drive the coordinated development of urbanization and ecosystem health differ based on periodic and regional characteristics. We need to tailor policies to ensure the sustainable development of the region
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