Buckling behavior of straight slot tubesunder oblique loading – A comparative study

Hollow tubes are the most important or crucial parts of the rapidly growing automobile and construction industry. The tube is subjected to pure buckling. In theanalysis, one end is fixed and the force is applied to theother end and by application of different angles of inclinations ranging from 0˚ to 20˚ with different thicknessof the range of 0.5 to 2.0. Linear buckling code was used forfinding the critical buckling load. This research paper is about the effects of buckling under oblique loading. It is the process in which the tube is subjected to compressive oblique loading and the tube fails by the first increase in crossectional area and then bulging on any of the sides but in the case, oblique loading in hollow tube shell bulges internally or inside the perimeter of the tube

Behavior of thin-walled tubes with combined cross-sectional geometries under oblique loading

Hollow tubes are the most important part of any structure because of their load-bearing capacity, lightweight and inexpensive manufacturing cost. One of the methods for improving the performance under quasi-static loading is to vary the cross-sectional shapes. In the real case, structures are seldom subjected to pure axial or pure bending rather they are subjected to a combination of two load cases i.e. oblique loading. In this paper, the circular cross-section was combined with four different polygonal cross-sections namely tetragon, hexagon, octagon and decagon and a total of 13 geometries were obtained. The buckling behavior of each tube was investigated numerically at various angles of inclination. Each tube was modeled in SOLIDWORKS and then was analyzed in ANSYS. Linear buckling code was used for finding the critical load at various angles ranging from 0° to 14°. The overall result was then compared and it was found that the proposed geometry can be a good alternative over conventional circular tubes in terms of load-bearing capacity at angular load

TUNNEL GEOLOGY AS SEEN BY GEOLOGISTS: MANHATTAN, NEW YORK CITY

Current exploratory boring operations in and around Manhattan, New York City are providing geologists and geotechnical engineers with a plethora of new and interesting geological information, which has not been previously reported. The rocks encountered, mostly medium to high-grade metamorphic rocks, with both mafic and felsic intrusives, are highly variable in competency and mechanical durability. One of the most frequently encountered rock types is a garnetiferous-muscovite-biotite schist which grades into schistose gneiss and displays a wide variety of structural, compositional, and textural attributes. Metamorphic minerals showing the variable degree of metamorphism include graphite, talc, garnet, kyanite, tourmaline, emory, and occasionally sillimanite. The presence of magnetite-rich zones within the muscovite-garnet schist suggests a mechanism for the concentration of iron during metamorphism. Concentrations of garnet both in the schist and intrusive pegmatite is perhaps indicative of anatectic melting of the protolith. Marble is the dominant rock type east of CAMERON\u27S LINE and it varies from pure white calcitic to dolomitic coarsely crystalline marble, to siliceous calcitic to dolomitic marble. In places, highly pyrite-rich zones, perhaps suggesting hydrothermal alteration of the parent rock due to subsequent mineral-rich fluid flow, are observed. The timing of the sulfide-rich fluid-flow through the original bedrock is yet to be determined. Partial dissolution of marble at various depths has resulted in void (cave) formation and has posed a threat to the boring operations. Rocks of lower abundance include amphibolite, granodiorite, quartzite, serpentinite, and aplite. The overall structural fabric is controlled by the Taconic and Acadian Orogenic events and manifested in the development of characteristic foliation, joint patterns, intrusives, and the degree of metamorphism of the protoliths

Soil Salinity Assessing and Mapping Using Several Statistical and Distribution Techniques in Arid and Semi-Arid Ecosystems, Egypt

Oasis lands in Egypt are commonly described as salty soils; therefore, waterlogging and higher soil salinity are major obstacles to sustainable agricultural development. This study aims to map and assess soil salinization at El-Farafra Oasis in the Egypt Western Desert based on salinity indices, Imaging Spectroscopy (IS), and statistical techniques. The regression model was developed to test the relationship between the electrical conductivity (ECe) of 70 surface soil samples and seven salinity indices (SI 1, SI 2, SI 5, SI 6, SI 7, SI 8, and SI 9) to produce soil salinity maps depending on Landsat-8 (OLI) images. The investigations of soil salinization and salinity indices were validated in a studied area based on 30 soil samples; the obtained results represented that all salinity indices have shown satisfactory correlations between ECe values for each soil sample site and salinity indices, except for the SI 5 index that present non-significant correlations with R2 value of 0.2688. The SI 8 index shows a higher negative significant correlation with ECe and an R2 value of 0.6356. There is a significant positive correlation at the (p < 0.01) level between SI 9 and ECe (r = 0.514), a non-significant correlation at the (p < 0.05) level between soil ECe and SI 1 index (r = 0.495), and the best-verified salinity index was for SI 7 that has a low estimated RMSE error of 8.58. Finally, the highest standard error (R2) was represented as ECe (dS m−1) with an R2 of 0.881, and the lowest one was SI 9 with an R2 of 0.428, according to Tukey’s test analysis. Therefore, observing and investigating soil salinity are essential requirements for appropriate natural resource management plans in the future

The accumulation of assembly intermediates of the mitochondrial complex I matrix arm is reduced by limiting glucose uptake in a neuronal-like model of MELAS syndrome

Ketogenic diet (KD) which combined carbohydrate restriction and the addition of ketone bodies has emerged as an alternative metabolic intervention used as an anticonvulsant therapy or to treat different types of neurological or mitochondrial disorders including MELAS syndrome. MELAS syndrome is a severe mitochondrial disease mainly due to the m.3243A > G mitochondrial DNA mutation. The broad success of KD is due to multiple beneficial mechanisms with distinct effects of very low carbohydrates and ketones. To evaluate the metabolic part of carbohydrate restriction, transmitochondrial neuronal-like cybrid cells carrying the m.3243A > G mutation, shown to be associated with a severe complex I deficiency was exposed during 3 weeks to glucose restriction. Mitochondrial enzyme defects were combined with an accumulation of complex I (CI) matrix intermediates in the untreated mutant cells, leading to a drastic reduction in CI driven respiration. The severe reduction of CI was also paralleled in post-mortem brain tissue of a MELAS patient carrying high mutant load. Importantly, lowering significantly glucose concentration in cell culture improved CI assembly with a significant reduction of matrix assembly intermediates and respiration capacities were restored in a sequential manner. In addition, OXPHOS protein expression and mitochondrial DNA copy number were significantly increased in mutant cells exposed to glucose restriction. The accumulation of CI matrix intermediates appeared as a hallmark of MELAS pathophysiology highlighting a critical pathophysiological mechanism involving CI disassembly, which can be alleviated by lowering glucose fuelling and the induction of mitochondrial biogenesis, emphasizing the usefulness of metabolic interventions in MELAS syndrome

Corporate Social Responsibility and Islamic Financial Institutions (IFIs): Management Perceptions from IFIs in Bahrain

Islamic finance is gaining greater attention in the finance industry, and this paper analyses how Islamic financial institutions (IFIs) are responding to the welfare needs of society. Using interview data with managers and content analysis of the disclosures, this study attempts to understand management perceptions of corporate social responsibility (CSR) in IFIs. A thorough understanding of CSR by managers, as evident in the interviews, has not been translated fully into practice. The partial use of IFIs’ potential role in social welfare would add further challenges in the era of financialisation

Istodobno spektrofotometrijsko određivanje losartan kalija, amlodipin besilata i hidroklorotiazida u farmaceutskim pripravcima kemometrijskom metodom

In the present work, four different spectrophotometric methods for simultaneous estimation of losartan potassium, amlodipine besilate and hydrochlorothiazide in raw materials and in formulations are described. Overlapped data was quantitatively resolved by using chemometric methods, classical least squares (CLS), multiple linear regression (MLR), principal component regression (PCR) and partial least squares (PLS). Calibrations were constructed using the absorption data matrix corresponding to the concentration data matrix, with measurements in the range of 230.5350.4 nm (∆λ = 0.1 nm) in their zero order spectra. The linearity range was found to be 840, 15 and 315 μg ml1 for losartan potassium, amlodipine besilate and hydrochlorothiazide, respectively. The validity of the proposed methods was successfully assessed for analyses of drugs in the various prepared physical mixtures and in tablet formulations.U radu su opisane četiri spektrofotometrijske metode za istodobno određivanje losartan kalija, amlodipin besilata i hidroklorotiazida u sirovinama i farmaceutskim pripravcima. Podaci koji su se preklapali kvantitativno su razlučeni kemometrijskim metodama, klasičnom metodom najmanjih kvadrata (CLS), multiplom linearnom regresijom (MLR), regresijom glavnih komponenata (PCR) te metodom parcijalnih najmanjih kvadrata (PLS). Kalibracije su provedene koristeći podatke o ovisnosti apsorpcije o koncentracijama, mjereći spektre nultog reda u rasponu 230,5350,4 nm (∆λ = 0,1 nm). Linearnost za losartan kalij bila je 840, za amlodipin besilat 15, a za hidroklorotiazid 315 μg ml1. Valjanost predloženih metoda uspješno je potvrđena analizom navedenih lijekova u različitim pripremljenim smjesama i tabletama

Tracking habitus across a transnational professional field

The sociology of the professions has shied away from cross-national comparative work. Yet research in different professional jurisdictions emphasizes the transnational nature of professional fields. Further work is therefore needed that explores the extent to which transnational professional fields are characterized by unity or heterogeneity. To that end, this article presents the results of a qualitative interrogation of the habitus of partners in ‘Big 4’ professional service firms across, primarily, five countries (Bangladesh, Canada, France, Spain and the UK). Marked differences are observed between the partner habitus in Bangladesh and the other countries studied in terms of entrepreneurial and public service dispositions. In turn, these findings highlight the methodological relevance of habitus for both the sociology of the professions and comparative capitalism literatures: for the former, habitus aids in mapping the dynamics of transnational professional fields; for the latter, habitus can elucidate the informal norms and conventions of national business systems

Pancreatic Tumor Microenvironmental Acidosis and Hypoxia Transform Gold Nanorods Into Cell-Penetrant Particles for Potent Radiosensitization

Coating nanoparticles with stealth epilayers increases circulation time by evading opsonization, macrophage phagocytosis, and reticuloendothelial sequestration. However, this also reduces internalization by cancer cells upon reaching the tumor. We designed gold nanorods (GNRs) with an epilayer that retains stealth properties in circulation but transforms spontaneously in the acidotic tumor microenvironment to a cell-penetrating particle. We used a customized stoichiometric ratio of l-glutamic acid and l-lysine within an amphiphilic polymer of poly(l-glutamic acid-co-l-lysine), or P(Glu-co-Lys), to effect this transformation in acidotic environments. P(Glu-co-Lys)-GNRs were internalized by cancer cells to facilitate potent in vitro radiosensitization. When administered intravenously in mice, they accumulate in the periphery and core of tumors without any signs of serum biochemical or hematological alterations, normal organ histopathological abnormalities, or overt deterioration in animal health. Furthermore, P(Glu-co-Lys)-GNRs penetrated the tumor microenvironment to accumulate in the hypoxic cores of tumors to potently radiosensitize heterotopic and orthotopic pancreatic cancers in vivo

A new estimate of carbon for Bangladesh forest ecosystems with their spatial distribution and REDD+ implications

In tropical developing countries, reducing emissions from deforestation and forest degradation (REDD+) is becoming an important mechanism for conserving forests and protecting biodiversity. A key prerequisite for any successful REDD+ project, however, is obtaining baseline estimates of carbon in forest ecosystems. Using available published data, we provide here a new and more reliable estimate of carbon in Bangladesh forest ecosystems, along with their geo-spatial distribution. Our study reveals great variability in carbon density in different forests and higher carbon stock in the mangrove ecosystems, followed by in hill forests and in inland Sal (Shorea robusta) forests in the country. Due to its coverage, degraded nature, and diverse stakeholder engagement, the hill forests of Bangladesh can be used to obtain maximum REDD+ benefits. Further research on carbon and biodiversity in under-represented forest ecosystems using a commonly accepted protocol is essential for the establishment of successful REDD+ projects and for the protection of the country’s degraded forests and for addressing declining levels of biodiversity