Machining and Tribological Characterisation of Uncoated and Coated Carbide Inserts while Turning Tungsten Heavy Alloy

Tungsten heavy alloys are high density alloys containing 80 to 98 wt.% tungsten and the balance is a matrix made of relatively low melting elements such as copper, nickel and iron. These alloys are used as radiation shields, CG adjusters and also in armour piercing ammunition. Machining these alloys to close tolerances and finish leads to excessive tool wear, surface damage and hence proves to be a challenging task. This study focuses on turning operation carried out under dry and wet cutting conditions using three different commercially available cemented carbide inserts. Three different feed rates have been used at a constant depth of cut and cutting speed. The best possible cemented carbide tooling solution for machining tungsten heavy alloys has been determined based on the surface finish obtained, chip geometry, cutting forces, and machining temperature. The observations made during machining are correlated to the tribological behavior of the inserts and the alloy with the help of pin-on disc tests. Coated cemented carbide inserts provide surface roughness values lower than 1 µm under finish turning conditions. On the other hand, PVD coated inserts give consistently better results over different feed rates and are found to experience lower tool wear for the specific cutting conditions. Analytical tool wear model suggests better tool life for the PVD coated insert

Investigating sources and sinks of N2O expression from freshwater microbial communities in urban watershed sediments

Wastewater treatment plants (WWTPs) serve as point-source inputs for a variety of nutrients often dominated by nitrogenous compounds as a result of anthropogenic influence. These effluents can impact biogeochemical cycles in freshwater estuaries, influencing microbial communities in both the water and sediment compartments. To assess the impact of point source nutrients, a transect of sediment and pore water samples were collected from 4 locations in the Little River Sub-watershed including locations above and below the Little River Pollution Control Plant (LRPCP). Variation in chemistry and microbial community/gene expression revealed significant influences of the effluent discharge on the adjacent sediments. Phosphorus and sulfur showed high concentrations within plume sediments compared to the reference sediments while nitrate concentrations were low. Increased abundance of denitrifiers Dechloromonas, Dok59 and Thermomonas correlating with increased expression of nitrous-oxide reductase suggests a conversion of N2O to N2 within the LRPCP effluent sediments. This study provides valuable insight into the gene regulation of microbes involved in N metabolism (denitrification, nitrification, and nitrite reduction to ammonia) within the sediment compartment influenced by wastewater effluent. © 2017 Elsevier Lt

Extracellular matrix-modulated expression of human cell surface glycoproteins A42 and J143. Intrinsic and extrinsic signals determine antigenic phenotype.

Extracellular matrix (ECM)' plays an important regulatory role in cellular growth, migration, and differentiation (1-4). Pathologic processes such as tumor cell invasion and metastasis are also determined by cellular interactions with ECM (5, 6). Biochemical studies have identified collagens, fibronectin, laminin, proteoglycans, and several other proteins as major ECM components (1-3), and have shown that ECM composition varies between different normal and tumor tissues. The complexity and heterogeneity of ECM composition have hampered the molecular analysis of ECM-cell interactions . However, a range of phenotypic changes has been described for cultured cells after transfer from plastic surfaces to substrates coated with native ECM (7, 8) or with purified ECM components; ECM-induced phenotypic changes include enhanced substrate adhesiveness, cell spreading and migration, changes in cell morphology and proliferative activity, and expression of differentiated cellular functions (I-4). Some of these effects, e.g., increased substrate adhesion, may result directly from the binding of specialized cell surface structures to ECM molecules. Others are likely mediated by an active cellular response triggered by the interaction of ECM with cell surface receptors. Thus, ECM-derived signals (9) may activate a cascade of molecular changes within the cell and on the cell surface that account for the pleiotropic effects observed with ECM

Disturbing Times: Medieval Pasts, Reimagined Futures

From Kehinde Wiley to W.E.B. Du Bois, from Nubia to Cuba, Willie Doherty’s terror in ancient landscapes to the violence of institutional Neo-Gothic, Reagan’s AIDS policies to Beowulf fanfiction, this richly diverse volume brings together art historians and literature scholars to articulate a more inclusive, intersectional medieval studies. It will be of interest to students working on the diaspora and migration, white settler colonialism and pogroms, Indigenous studies and decolonial methodology, slavery, genocide, and culturecide. The authors confront the often disturbing legacies of medieval studies and its current failures to own up to those, and also analyze fascist, nationalist, colonialist, anti-Semitic, and other ideologies to which the medieval has been and is yoked, collectively formulating concrete ethical choices and aims for future research and teaching. In the face of rising global fascism and related ideological mobilizations, contemporary and past, and of cultural heritage and history as weapons of symbolic and physical oppression, this volume’s chapters on Byzantium, Medieval Nubia, Old English, Hebrew, Old French, Occitan, and American and European medievalisms examine how educational institutions, museums, universities, and individuals are shaped by ethics and various ideologies in research, collecting, and teaching

A 3-Mb High-Resolution BAC/PAC Contig of 12q22 Encompassing the 830-kb Consensus Minimal Deletion in Male Germ Cell Tumors

Cytogenetic and molecular genetic analyses have shown that the 12q22 region is recurrently deleted in male germ cell tumors (GCTs), suggesting that this site may harbor a tumor suppressor gene (TSG). Previous loss of heterozygosity (LOH) analyses identified a consensus minimal deleted region between the markers D12S377 and D12S296, and a YAC clone contig covering the region was generated. Here, we describe a high-resolution sequence-ready physical map of this contig covering a 3-Mb region. The map comprised of 52 cosmids, 49 PACs, and 168 BACs that were anchored to the previous YAC contig; 99 polymorphic, nonpolymorphic, EST, and gene-based markers are now placed on this map in a unique order. Of these, 61 markers were isolated in the present study, including one that was polymorphic. In addition, we have narrowed the minimal deletion to ∼830 kb between D12S1716 (proximal) and P382A8-AG (distal) by LOH analysis of 108 normal-tumor DNAs from GCT patients using 21 polymorphic STSs. These physical and deletion maps should prove useful for identification of the candidate TSG in GCTs, provide framework to generate complete DNA sequence, and ultimately generate a gene map of this segment of the chromosome 12

Effect of COD: SO42- Ratio, HRT and Linoleic Acid Concentration on Mesophilic Sulfate Reduction: Reactor Performance and Microbial Population Dynamics

Biological sulfate (SO42-) reduction was examined in anaerobic sequential batch reactors (ASBRs) operated under different hydraulic retention times (HRTs) ranging from 12 to 36 h and COD (Chemical Oxygen Demand)/SO42- ratios of 2.4, 1.6 and 0.8. Competition between SO42- reducing bacteria (SRBs), methane producing archaea (MPAs) and homoacetogens (HACs) was examined in controls and cultures treated with linoleic acid (LA). The ASBR performance was influenced by the COD/SO42- ratio in control cultures with a SO42- reduction of 87% at a COD/SO42- ratio of 0.8. At a 12 h HRT, in both control and LA treated cultures, greater than 75% SO42- removal was observed under all the conditions examined. In control reactors operating at a 36 h HRT, high levels of MPAs belonging to Methanobacteriales and Methanosarcinales were detected; however, in comparison, under low COD/SO42- ratio and with decreasing HRT conditions, a relative increase in SRBs belonging to Desulfovibrio and Desulfatibacillum was observed. Adding 0.5 gL(-1) LA suppressed Methanobacteriales, while increasing the LA concentration to 1 gL(-1) completely suppressed MPAs with a relative increase in SRBs. HACs belonging to Bacteroidetes were observed in the control and in cultures operated at 12 h HRT with a COD/SO42- ratio of 1.6 and fed 0.5 gL(-1) LA; however, with all other LA levels (0.5 and 1.0 gL(-1)) and HRTs (12, 24 and 36 h), HACs were not detected

Variations in lung fissures and lobes morphology in population of Andhra Pradesh of South India (a cadaveric study)

Knowledge of the position of lung fissures is necessary for the appreciation of lobar anatomy and thus locating the bronchopulmonary segments. The study aimed to investigate the patterns of fissures and lobes of the lungs and their variations in Andhra Pradesh, India and to find their clinical implications and compare them with the previous studies. Methods: The patterns of lobes, fissures, and hilar anatomy of lungs and its variations of 47 lungs by dissection method of embalmed cadavers was performed in the Department of Anatomy, Narayana Medical College (Nellore, India). The specimens were macroscopically observed for gross morphology of fissures and lobes. Results. The study showed oblique fissure in 33 % (grade 1), 26 % (grade 2), 24 % (grade 3) and 14 % (grade 4) of right lungs and 27 % (grade 1), 31 % (grade 2), 12 % (grade 3) and 12 % (grade 4) of left lungs. The incomplete horizontal fissure was seen in 38 % of right-sided lungs (grade 1). 19 % of right lungs and 10 % of left lungs had accessory lung fissures. Conclusions. Awareness of the variations in the lobes and fissures of the lungs is important for radiologists while interpreting magnetic resonance imaging and computed tomography scans. Also, we believe that the data from the present study certainly adds an important reference in the medical literature to thoracic surgeons in performing pneumonectomy and segmental resection

Anatomical deviations in the position of vermiform appendix: the cadaveric study

Vermiform appendix is the only organ in the body that has no constant anatomical position. It is so named because of its worm like appearance. Most common surgical cause of abdominal pain is appendicitis; its diagnosis is affected by anatomical variations of the vermiform appendix, because this is the most variable abdominal organ in terms of position and organ relations. Aim of the study was to examine anatomical features and different positions of the vermiform appendix in human cadavers. Material and methods. This study was carried on 45 human cadavers irrespective of sex and age from the Department of Anatomy at Andhra Pradesh over a period of 12 months. Results. Mean length of appendix was found to be 3.98 ± 1.27 cm. Mean outer girth was 2.17 ± 0.26 cm. Mean distance of vermiform appendix from ileocaecal junction was found to be 2.11 ± 0.43 cm. Commonest position was retrocaecal (44 %), followed by pelvic (21 %), postileal (9 %), subcaecal (13 %) and midinguinal (10 %). Conclusions. Variations in position of vermiform appendix will help the surgeons to make a diagnosis of appendicitis and aware about appendiceal rupture

The role of competencies in shaping the leadership style of female entrepreneurs: the case of North West of England, Yorkshire, and North Wales

This study investigates linkages between personal competencies and leadership style among female small and micro business owners. Although prior research suggests that leadership style is shaped according to a leader's traits and abilities, few empirical studies corroborate this, particularly among female owners. Using survey data from the North West of England, Yorkshire, and North Wales, we reveal that transformational leadership style is the most dominant style adopted, and it is linked to perceived human and personal competencies as well as entrepreneurial competencies