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Author(s):  
Bayi Bage

Abstract: ETABS Stand for Extended Three-Dimensional Analysis of Building systems. ETABS integrates every aspect of the engineering design process. In the present situations of construction industry, the buildings that are being constructed are gaining significance, in general those with the best possible outcomes which are referred to members like beams and columns in multi storeys R.C structures. This paper deals with the seismic analysis of regular B+G+26 story building with shear wall and G+B+10 Story building with different irregular shapes considering different shapes of shear wall at different locations has been carried out. Which can be done in ETABS taking all the considerations regarding codes and other factors into account. All the buildings were analyzed with the same method as stated in IS 1893-Part-1:2016. The effect of shear walls on lateral capacity of the building are examined because the seismic analysis of a frame depends upon the location and symmetry of shear wall. Present study shows the shear wall improves not only the lateral stiffness and strength capacity but also the displacement capacity of structure. Comparison of results been done of different models by comparing the parameters such as story drift, story displacement, story stiffness and base reaction. Therefore, as far as possible irregularities in a building must be avoided. But, if irregularities have to be introduced for any reason, they must be designed properly following the conditions of IS 13920:1993. The complex shaped buildings are now days getting popular, but they carry a risk of sustaining damages during earthquakes. Keywords ETABS Software; IS Code 1892-Part-1:2016; IS Code 13920:1993; IS Code 875-Part-1 and Part-2


Author(s):  
Feng Zhou ◽  
Yan Xu ◽  
Xiaoqing Mu ◽  
Yao Nie

In this study, a novel enzymatic approach to transform levulinic acid (LA), which can be obtained from biomass, into value-added (R)-4-aminopentanoic acid using an engineered glutamate dehydrogenase from Escherichia coli (EcGDH) was developed. Through crystal structure comparison, two residues (K116 and N348), especially residue 116, were identified to affect the substrate specificity of EcGDH. After targeted saturation mutagenesis, the mutant EcGDHK116C, which was active toward LA, was identified. Screening of the two-site combinatorial saturation mutagenesis library with EcGDHK116C as positive control, the kcat/Km of the obtained EcGDHK116Q/N348M for LA and NADPH were 42.0- and 7.9-fold higher, respectively, than that of EcGDHK116C. A molecular docking investigation was conducted to explain the catalytic activity of the mutants and stereoconfiguration of the product. Coupled with formate dehydrogenase, EcGDHK116Q/N348M was found to be able to convert 0.4 M LA by more than 97% in 11 h, generating (R)-4-aminopentanoic acid with >99% enantiomeric excess (ee). This dual-enzyme system used sustainable raw materials to synthesize (R)-4-aminopentanoic acid with high atom utilization as it utilizes cheap ammonia as the amino donor, and the inorganic carbonate is the sole by-product.


Author(s):  
Diana Hlushkova ◽  
Valeriy Bagrov

Today, one of the important problems of mechanical engineering is to increase the reliability and durability of machines. A special place in this matter is occupied by increasing the wear resistance of parts. As for diesel construction, the problem of increasing the hardness and wear resistance of piston rings is very important. Goal. The goal is study of the structure and nature of changes in the hardness of the surface layer obtained by gas-thermal combined spraying, after grinding, running-in and mileage of the diesel engine, i. e., at all stages of the production cycle. Methodology. The coating on the rings was applied by the method of two-wire metallization with independent supply of wires made of 11X18M steel and molybdenum. Metallographic analysis was used to study the structure of the obtained coating. The condition of the surface layer after coating, grinding, running-in and diesel run was studied by measuring the microhardness. Results. Metallographic analysis of the interface between steel and molybdenum coating – cast iron for many rings and different parts of one ring shows that the coating interacts closely with the substrate along the entire application profile. The structure of molybdenum particles demonstrates their fineness. This is due to the fact that the rapid crystallization under pressure contributes to the creation of a fine-grained structure. Comparison of the microhardness of molybdenum and steel wires with steel-molybdenum coating indicates a significant strengthening of molybdenum and steel particles during spraying, due to the processes of structure formation. Experimental data indicate the stability of the hardness of both molybdenum particles and steel particles, which is important for the coating in operation. Originality. Features of formation of a gas-thermal covering at a simultaneous electric arc spraying of molybdenum and 11Х18М steel on piston rings from pig-iron are established. It is shown that a layered structure is formed, which consists mainly of steel and molybdenum particles. The reasons for the wide range of properties of steel and molybdenum particles have been clarified. It is proved that the operational properties of steel-molybdenum coating are due to its antifriction properties, porosity, which provides self-lubrication of the friction surface, good adhesion to the substrate, which increases by 3–4 times compared to traditional methods. Practical value. The proposed technology of gas-thermal spraying significantly increases the service life of piston rings operating in wear conditions.


2021 ◽  
pp. 131609
Author(s):  
Yishu Yan ◽  
Panpan Ren ◽  
Qingqing Wu ◽  
Xiaoni Liu ◽  
Zhenqing Zhang ◽  
...  
Keyword(s):  

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
De-Sheng Ker ◽  
Hong Xi Sha ◽  
Mohd Anuar Jonet ◽  
Jung Shan Hwang ◽  
Chyan Leong Ng

AbstractActinoporins are a family of α-pore-forming toxins (α-PFTs) that have been identified in sea anemones. Recently, a freshwater Hydra Actinoporin-Like Toxin (HALT) gene family was found in Hydra magnipapillata. Unlike sea anemone actinoporins that use sphingomyelin as their main recognition target, the HALTs proteins may recognise alternative lipid molecules as their target. To unveil the structural insights into lipid preference of HALTs protein as compared to sea anemone actinoporins, we have determined the first crystal structure of actinoporin-like toxin, HALT-1 at 1.43 Å resolution with an acetylated lysine residue K76. Despite the overall structure of HALT-1 sharing a high structural similarity to sea anemone actinoporins, the atomic resolution structure revealed several unique structural features of HALT-1 that may influence the lipid preference and oligomerisation interface. The HALT-1 contains a RAG motif in place of the highly conserved RGD motif found in sea anemone actinoporins. The RAG motif contributed to a sharper β9-β10 turn, which may sway its oligomerisation interface in comparison to sea anemone actinoporins. In the lipid-binding region, the HALT-1 contains a shorter α2 helix and a longer α2-β9 loop due to deletion and subsequently an insertion of five amino acid residues in comparison to the sea anemone actinoporins. Structure comparison and molecular docking analysis further revealed that the HALT-1 lipid-binding site may favour sphingolipids with sulfate or phosphate head group more than the sphingomyelin. The structure of HALT-1 reported here provides a new insight for a better understanding of the evolution and lipid recognition mechanism of actinoporin.


PLoS ONE ◽  
2021 ◽  
Vol 16 (10) ◽  
pp. e0245822
Author(s):  
Gunjan Katyal ◽  
Brad Ebanks ◽  
Magnus Lucassen ◽  
Chiara Papetti ◽  
Lisa Chakrabarti

Mitochondrial changes such as tight coupling of the mitochondria have facilitated sustained oxygen and respiratory activity in haemoglobin-less icefish of the Channichthyidae family. We aimed to characterise features in the sequence and structure of the proteins directly involved in proton transport, which have potential physiological implications. ATP synthase subunit a (ATP6) and subunit 8 (ATP8) are proteins that function as part of the F0 component (proton pump) of the F0F1complex. Both proteins are encoded by the mitochondrial genome and involved in oxidative phosphorylation. To explore mitochondrial sequence variation for ATP6 and ATP8 we analysed sequences from C. gunnari and C. rastrospinosus and compared them with their closely related red-blooded species and eight other vertebrate species. Our comparison of the amino acid sequence of these proteins reveals important differences that could underlie aspects of the unique physiology of the icefish. In this study we find that changes in the sequence of subunit a of the icefish C. gunnari at position 35 where there is a hydrophobic alanine which is not seen in the other notothenioids we analysed. An amino acid change of this type is significant since it may have a structural impact. The biology of the haemoglobin-less icefish is necessarily unique and any insights about these animals will help to generate a better overall understanding of important physiological pathways.


2021 ◽  
Author(s):  
Liam M. Longo ◽  
Rachel Kolodny ◽  
Shawn E. McGlynn

AbstractAs sequence and structure comparison algorithms gain sensitivity, the intrinsic interconnectedness of the protein universe has become increasingly apparent. Despite this general trend, β-trefoils have emerged as an uncommon counterexample: They are an isolated protein lineage for which few, if any, sequence or structure associations to other lineages have been identified. If β-trefoils are, in fact, remote islands in sequence-structure space, it implies that the oligomerizing peptide that founded the β-trefoil lineage itself arose de novo. To better understand β-trefoil evolution, and to probe the limits of fragment sharing across the protein universe, we identified both ‘β-trefoil bridging themes’ (evolutionarily-related sequence segments) and ‘β-trefoil-like motifs’ (structure motifs with a hallmark feature of the β-trefoil architecture) in multiple, ostensibly unrelated, protein lineages. The success of the present approach stems, in part, from considering β-trefoil sequence segments or structure motifs rather than the β-trefoil architecture as a whole, as has been done previously. The newly uncovered inter-lineage connections presented here suggest a novel hypothesis about the origins of the β-trefoil fold itself – namely, that it is a derived fold formed by ‘budding’ from an Immunoglobulin-like β-sandwich protein. These results demonstrate how the emergence of a folded domain from a peptide need not be a signature of antiquity and underpin an emerging truth: few protein lineages escape nature’s sewing table.


2021 ◽  
Vol 23 (Supplement_2) ◽  
pp. ii36-ii37
Author(s):  
A M Kopylov ◽  
N Samoylenkova ◽  
A Bizayeva ◽  
A Arutyunyan ◽  
V Tashlitsky ◽  
...  

Abstract BACKGROUND G-quadruplex oligonucleotides (GQs) exhibit specific anti-survival activity in human cancer cell lines; they can selectively inhibit the viability/proliferation. The most studied, AS1411, had been in clinical trials. This anti-proliferative ability of GQs could be translated into glioma, which currently has poor prognosis and low-efficiency therapeutic treatments for glioblastoma multiform (GBM). Set of GQs have been designed, synthesized, and tested: they have different amount of Q-quartets, they have dimers of different GQ modules: either covalent dimers or non-covalent ones; all of them could be coined as ‘twins’. MATERIAL AND METHODS Folding of synthetic DNA oligonucleotides into GQs and thermal stability have been studied by circular dichroism, melting with unfolding-folding regimes, oligomerization was followed by original SE-HPLC. Conventional human cell lines U87 and fibroblasts from human embryo (HEF) were provided from the collection of the Centre of Neurosurgery (Moscow, Russia). GBM primary cell cultures N1, G11, Sus/fP2, G22, G23, and G01 were developed in Burdenko National Medical Research Centre of Neurosurgery (NMRCN) from the surgery samples of patients (PCC_SSP). All samples had WT IDH1. This study was approved by the Ethics Committee of Burdenko NMRCN, Russian Academy of Medical Sciences (№_12/2020, 15.12.2020). All subjects gave written informed consent in accordance with the guidelines of Declaration of Helsinki. Cell viability was tested by conventional MTT-test. RESULTS Novel bi-modular GQ, bi-(AID-1-T), twin of three-quartet AID-1-T, was designed by covalent conjugation of two AID-1-Ts via three thymidine link, TTT; and linking did not interfere with its GQ structure. Comparison of bi-(AID-1-T) with mono-modular AID-1-T, mono-modular two-quartet HD1, bi-modular bi-HD1, and two-quartet AS1411, was made. Among five GQs, bi-(AID-1-T) had the highest anti-survival activity for U87, while not affecting the control, HEF. GQs, for the first time, were tested on several PCC_SSP. Sensitivity of PCC_SSP toward GQs varied, with apparent IC50 of less than 1 μM for bi-(AID-1-T) toward the most sensitive G11 (glioma, Grade III). CONCLUSION GQs as anti-proliferative crypto-aptamers with moderate activity due to restricted functioning of apparent GQ-binding proteins could be applied toward real glioma PCC_SSP. Variety of effects reflects glioma inter-tumor heterogeneity.Research was funded by Ministry of Education and Science of Russia, grant number № 075-15-2020-809 (13.1902.21.0030) and by Russian Foundation for Basic Research, grants number №18-29-01047


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