Numerical Study for the Behavior of Stainless-Steel Sigma Columns Under Axial Compression Load

This study investigated numerically the behavior of slender austenitic stainless-steel grade EN 1.4420 columns under compression loads. The column has a single lipped Sigma cross section. The finite element model was developed using ABAQUS software, then it was validated by comparing its results against outcomes from a previous experimental study. A parametric study conducted on pin-ended Sigma columns explores the effect of various factors on ultimate strength and failure modes, such as thickness (t) and flange width (B). Results indicate that as the thickness of the column increases, so does its ultimate load capacity. Thicker columns tend to fail due to global buckling. The ultimate capacity increases as the flange width (B) increases from 60 mm to 75 mm, remains constant as the flange width (B) increases from 75 mm to 100 mm, and starts to decrease when the flange width (B) exceeds 100 mm. Comparing carbon steel and austenitic stainless steel Sigma columns, the latter shows a 34% increase in bearing capacity

Experimental Shear Behavior of Fiber Reinforced Composite Corrugated Plate Girders at Intermediate Supports

Bridges with corrugated steel webs have been extensivelyconstructed in different countries. A trapezoidally corrugatedsteel plate is composed of a series of longitudinal andinclined subpanels. For a steel corrugated web girder, it isassumed that the web carries merely shear forces due to theaccordion effect [1,2]. The web in such a girder was found tocarry insignificant longitudinal stresses from the primaryflexure. Consequently, the bending moment is nearly carriedby its flanges. Thus, it is worth pointing out that the shearstrength can be determined without consideration ofmoment-shear interaction. But it was found that problem inan area where intermediate supports that shear forces arecompletely carried by web, and found that the value of theshear resistance, which is a concrete slab by almost beneglected. In recent years has been the study of differenttypes of materials to increase the efficiency of concrete andincrease the shear forces at the intermediate supports. Thusin this research, the effect of adding fiber to the concrete incomposite corrugated plate girders at intermediate supportswas investigated

Mejora de la producción de lípidos de un prometedor hongo oleaginoso Aspergillus sp. cepa EM2018 para la formación de biodiesel: optimización de las condiciones de cultivo e identificación

Oleaginous fungi have recently gained increasing attention among different microorganisms due to their ability for lipid production for the preparation of biofuel. In the present study, a locally isolated fungus E45, identified genetically as Aspergillus sp. strain EM2018, was found to produce 25.2% of the total lipids content of its dry cell weight (DCW). Optimization of culture conditions was performed and lipid accumula­tion increased by about 2.4 fold (from 25.2% to 60.1% of DCW) when the fungus was grown for seven days in the potato dextrose (50 g/L) liquid medium at pH 5.0, incubation temperature at 30 ºC and inoculum size of 2 × 106 spore/mL. Supplementation of the medium with yeast extract and NaNO3 at a concentration of 0.05% as organic and inorganic nitrogen sources, respectively, increased lipid production (53.3% lipid/dry biomass). Gas chromatography analysis of fungal lipids revealed the presence of saturated (mainly palmitic acid C16:0 (33%) and lignoceric acid C24:0 (15%)) and unsaturated fatty acids in different proportions (mainly linoleic acid C18:2 (24.4%), oleica cid C18:1 (14%) and arachidonic C20:4 (7.4%). These findings suggest this new oleaginous fungus as a promising feedstock for various industrial applications and for the preparation of biodiesel.Los hongos oleagino­sos recientemente están ganando una creciente atención entre diferentes microorganismos debido a sus capaci­dades de producción de lípidos para la preparación de biocombustibles. En el presente estudio, se descubrió que un hongo E45 aislado localmente, identificado genéticamente como la cepa Aspergillus sp. EM2018, produce un 25,2% de lípidos totales de su peso de células secas (DCW). Se realizó la optimización de las condiciones de cultivo y la acumulación de lípidos se incrementó aproximadamente 2,4 veces (del 25,2% al 60,1% de DCW) cuando el hongo creció durante siete días en un medio líquido de dextrosa de papa (50 g/L) a pH 5.0, 30 °C de temperatura de incubación y 2 × 106 esporas/ml de tamaño de inóculo. La suplementación del medio con extracto de leva­dura y NaNO3 a una concentración de 0,05% como fuentes de nitrógeno orgánico e inorgánico, respectivamente, aumentó aún más la producción de lípidos (53,3% de lípidos/biomasa seca). El análisis mediante cromatografía de gases de los lípidos fúngicos reveló la presencia de ácidos grasos saturados (principalmente palmítico C16:0 (33%) y lignocérico C24:0 (15%)) y ácidos grasos insaturados en diferentes proporciones (principalmente linoleico C18:2 (24.4%), oleico C18:1 (14%) y araquidónico C20:4 (7,4%). Estos hallazgos sugieren que este nuevo hongo oleaginoso es una materia prima prometedora para diversas aplicaciones industriales y preparación de biodiésel

Is rejection a diffuse or localized process in small-bowel transplantation?

Utilization of endoscopy to both visualize and selectively biopsy an intestinal allograft has become the standard for early recognition and treatment of intestinal allograft rejection. Despite the widespread acceptance of the need for selective mucosal biopsies, it has not been shown that the histological features of intestinal allograft rejection are either localized or occur as part of a more diffuse phenomenon within a tubular allograft. To resolve these issues, 88 ileoscopies were performed in 12 small-bowel allograft recipients and mucosal biopsy samples were obtained at 5, 10, and 15 cm, respectively, from the ileal stoma. Each mucosal biopsy was labeled, processed, and evaluated individually for the presence and severity of any evidence for allograft rejection. The data obtained suggest that intestinal allograft rejection is a diffuse process, and biopsies obtained randomly from an ileal graft are likely to demonstrate evidence of allograft rejection when such is present. © 1994 Springer-Verlag New York Inc

Polyphenolic constituents and antimicrobial activity of Rhapis excels (Arecaceae, Coryphoideae).

The chromatographic fractionation of Rhapis excelsa f.,Arecaceae, leaves extract, a plant known aslady palm, resulted in the isolation of four flavonoids: Apigenin-8-C-glucoside (vitexin), Apigenin-6,8-Di-C-βglucopyranoside (vicenin-2), Luteolin-6-C-glucoside (isoorientin) and Luteolin-8-C-glucoside (orientin). Thestructural elucidations of these compounds were performed by means of the comparison of their spectral data(UV systematic identification and 1NMR) with those ones of the literature. Ethyl acetate and butanol fractionsshowed remarkable antioxidant activity (86.2 and 75.6 respectively), when investigated for their DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity. The major polyphenols were identified, as benzoic acid,ferulic acid with others by means of RP-HPLC, they were quantified in methanolic crude extract. Also, theantibacterial activity of the extract was assessed against Staphylococcus aureusstrains, including methicillinresistant S. aureus (MRSA). The extracts had no antimicrobial activity alone but they revealed ability topotentiate the antibacterial activity of ciprofloxacin, tetracycline and oxacillin

Farnesol attenuates cadmium-induced kidney injury by mitigating oxidative stress, inflammation and necroptosis and upregulating cytoglobin and PPARγ in rats

Heavy metals are environmental pollutants that can harm animals and humans even at low concentrations. Cadmium (Cd) is known for its serious health effects on different organs and its toxicity is associated with oxidative stress (OS) and inflammation. Farnesol (FAR), a sesquiterpene alcohol found in many vegetables and fruits, possesses promising anti-inflammatory and antioxidant activities. This study evaluated the effect of FAR on Cd-induced kidney injury, pinpointing its effect of the redox status, inflammation, fibrosis and necroptosis. Rats in this study received FAR for 14 days and Cd on day 7. Elevated serum creatinine, urea and uric acid, and several kidney histopathological alterations were observed in Cd-administered rats. Cd increased MDA, decreased antioxidants, downregulated PPARγ and upregulated NF-κB p65, IL-6, TNF-α, and IL-1β. Necroptosis mediators (RIP1, RIP3, MLKL, and caspase-8) and α-SMA were upregulated, and collagen deposition was increased in Cd-administered rats. FAR ameliorated kidney injury markers and tissue damage, attenuated OS, suppressed NF-κB and inflammatory mediators, and enhanced antioxidants. In addition, FAR suppressed RIP1, RIP3, MLKL, caspase-8, and α-SMA, and enhanced kidney cytoglobin and PPARγ. In conclusion, FAR protects against Cd nephrotoxicity by suppressing OS, inflammatory response and necroptosis, effects associated with enhanced antioxidants, cytoglobin, and PPARγ

Protease activity of some mesophilic streptomycetes isolated from Egyptian habitats

Different streptomycetes (317 isolates) were obtained from several sources and areas in Egypt and were screened for proteolytic activity. Thirty nine of them produced proteases and were subjected to identification. Streptomyces anulatus formed the most abundant portion of the isolates. This species deserves special attention because it is a good candidate for biotechnological applications

An update on advances in magnetic resonance imaging of multiple system atrophy

In this review, we describe how different neuroimaging tools have been used to identify novel MSA biomarkers, highlighting their advantages and limitations. First, we describe the main structural MRI changes frequently associated with MSA including the 'hot cross-bun' and 'putaminal rim' signs as well as putaminal, pontine, and middle cerebellar peduncle (MCP) atrophy. We discuss the sensitivity and specificity of different supra- and infratentorial changes in differentiating MSA from other disorders, highlighting those that can improve diagnostic accuracy, including the MCP width and MCP/superior cerebellar peduncle (SCP) ratio on T1-weighted imaging, raised putaminal diffusivity on diffusion-weighted imaging, and increased T2* signal in the putamen, striatum, and substantia nigra on susceptibility-weighted imaging. Second, we focus on recent advances in structural and functional MRI techniques including diffusion tensor imaging (DTI), resting-state functional MRI (fMRI), and arterial spin labelling (ASL) imaging. Finally, we discuss new approaches for MSA research such as multimodal neuroimaging strategies and how such markers may be applied in clinical trials to provide crucial data for accurately selecting patients and to act as secondary outcome measures