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41.
This paper reports an investigation into new connection types and their behaviors determined using full-scale experiments. T-shaped connections were created using the IPE standard profile. The aim of this study was to analyze the influence of T connections based on the IPE standard profile, height of beam to height of T-stub joint (H) of T-stub joints, and lengths (X) of T-stub joints on the behavior of steel connections, in order to provide the necessary data for improving Eurocode 3 and enable efficient use of residue IPE standard profiles and back to the consumption cycle. While the moment resistance values increased with an increase in H from Hmin to Hmax in model groups with X of 126 mm, and the energy dissipation increased with an increase in H from Hmin to Hmax and also with an increase in the lengths (X) of T-stub joints from 54 to 126 mm. 相似文献
42.
Sucasas Victor Mantas Georgios Althunibat Saud Ortega José-Fernán Martínez 《Mobile Networks and Applications》2020,25(1):151-152
Mobile Networks and Applications - 相似文献
43.
44.
Dr. Camila M. Crnkovic Dr. Jana Braesel Dr. Aleksej Krunic Prof. Dr. Alessandra S. Eustáquio Prof. Dr. Jimmy Orjala 《Chembiochem : a European journal of chemical biology》2020,21(6):845-852
Cyanobactins are a large family of cyanobacterial ribosomally synthesized and post-translationally modified peptides (RiPPs) often associated with biological activities, such as cytotoxicity, antiviral, and antimalarial activities. They are traditionally described as cyclic molecules containing heterocyclized amino acids. However, this definition has been recently challenged by the discovery of short, linear cyanobactins containing three to five amino acids as well as cyanobactins containing no heterocyclized residues. Herein we report the discovery of scytodecamide ( 1 ) from the freshwater cyanobacterium Scytonema sp. UIC 10036. Structural elucidation based on mass spectrometry, 1D and 2D NMR spectroscopy, and Marfey's method revealed 1 to be a linear decapeptide with an N-terminal N-methylation and a C-terminal amidation. The genome of Scytonema sp. UIC 10036 was sequenced, and bioinformatic analysis revealed a cyanobactin-like biosynthetic gene cluster consistent with the structure of 1 . The discovery of 1 as a novel linear peptide containing an N-terminal N-methylation and a C-terminal amidation expands the chemical and genetic diversity of the cyanobactin family of compounds. 相似文献
45.
Maria Jos Rodríguez Francisca Herrera Wendy Donoso Ivn Castillo Roxana Orrego Daniel R. Gonzlez Jessica Zúiga-Hernndez 《International journal of molecular sciences》2020,21(22)
Liver fibrosis is a complex process associated to most types of chronic liver disease, which is characterized by a disturbance of hepatic tissue architecture and the excessive accumulation of extracellular matrix. Resolvin E1 (RvE1) is a representative member of the eicosapentaenoic omega-3 lipid derivatives, and is a drug candidate of the growing family of endogenous resolvins. Considering the aforementioned, the main objective of this study was to analyze the hepatoprotective effect of RvE1 in a rat model of liver fibrosis. Male Sprague-Dawley rats received diethylnitrosamine (DEN, 70 mg/mg body weight intraperitoneally (i.p)) as an inductor of liver fibrosis once weekly and RvE1(100 ng/body weight i.p) twice weekly for four weeks. RvE1 suppressed the alterations induced by DEN, normalizing the levels of alanine aminotransferase (ALT), albumin, and lactate dehydrogenase (LDH), and ameliorated DEN injury by decreasing the architecture distortion, inflammatory infiltration, necrotic areas, and microsteatosis. RvE1 also limited DEN-induced proliferation through a decrease in Ki67-positive cells and cyclin D1 protein expression, which is related to an increase of the levels of cleaved caspase-3. Interestingly, we found that RvE1 promotes higher nuclear translocation of nuclear factor κB (NF-κB)p65 than DEN. RvE1 also increased the levels of nuclear the nuclear factor erythroid 2–related factor 2 (Nrf2), but with no antioxidant effect, measured as an increase in glutathione disulfide (GSSG) and a decrease in the ratio of glutathione (GSH)/GSSG. Taken together, these results suggest that RvE1 modulates the fibrogenesis, steatosis, and cell proliferation in a model of DEN induced fibrosis. 相似文献
46.
In solution, amphoteric compounds exist in anionic, uncharged, zwitterionic and cationic forms. The importance of zwitterionic drugs is currently under-represented in the literature. Herein, the acid-base parameters, lipophilicity and solubility of such compounds are discussed to deepen the molecular-level understanding of their pharmacokinetic and pharmacodynamic behaviour. Our recent studies show there are many drug molecules, including thyroid hormones and 5-hydroxytryptophan, the precursor of the neurotransmitter serotonin, for which the contribution of the zwitterionic microspecies to the overall lipophilicity exceeds that of the uncharged one, which is of higher individual lipophilicity, but occurs in much lower concentration. The second part of the minireview highlights the most important zwitterionic compounds in therapy, grouped into therapeutic classes. The importance of the charge of the molecules is emphasized in their binding to the target molecules. 相似文献
47.
Minds and Machines - In the last 20 years the Turing test has been left further behind by new developments in artificial intelligence. At the same time, however, these developments have revived... 相似文献
48.
Concentration of Gamma‐Linolenic and Stearidonic Acids as Free Fatty Acids and Ethyl Esters from Viper's Bugloss Seed Oil by Urea Complexation 下载免费PDF全文
49.
J. A. Dávila-Pintle E. Reynoso-Lara Y. E. Bravo-García 《Journal of Materials Science: Materials in Electronics》2018,29(18):15358-15362
Samples were grown on glass substrates of CdS doped with different levels of indium via the chemical bath technique. The samples obtained were optically characterized to determine their band-gap. A capacitor of parallel plates is constructed with the CdS samples placed between the plates; afterward, light with energy above the band-gap is used to generate carriers in the CdS to modify its dielectric properties and therefore the capacitance. The sample that causes greater current through the capacitor is used to form part of the tank circuit of a bandpass filter because this tank circuit determines the frequency of resonance or passage of the filter, thus forming a bandpass filter whose resonance frequency depends on the intensity of light that impinges on the CdS sample. Finally, the frequency responses of the filter when the sample is not illuminated compared to that when it is illuminated are studied to demonstrate a filter whose resonance frequency can be effectively controlled by light via the use of indium-doped CdS. 相似文献
50.
Federico Martín Bergero Francesco Casella Ernesto Kofman Joaquín Fernández 《Building Simulation》2018,11(2):405-418
Models describing energy consumption, heating, and cooling of buildings usually impose difficulties to the numerical integration algorithms used to simulate them. Stiffness and the presence of frequent discontinuities are among the main causes of those difficulties, that become critical when the models grow in size. Quantized State Systems (QSS) methods are a family of numerical integration algorithms that can efficiently handle discontinuities and stiffness in large models. For this reason, they are promising candidates for overcoming the mentioned problems. Based on this observation, this article studies the performance of QSS methods in some systems that are relevant to the field of building simulation. The study includes a performance comparison of different QSS algorithms against state-of-the-art classic numerical solvers, showing that the former can be more than one order of magnitude faster. 相似文献