Effect of cryogenic treatment on drill tool for enhancing metal cutting operation of aluminium alloy IS737.Gr19000

Drilling is the hole making process on the component face with the aid of a twisted drillbit. Normal drill bits easily wear out through penetration of drill bit into the workpiece material due to force generated in the drilling operation. So this work tries to investigate the machining parameters with cryogenically treated drill bits on various responses. Cryogenic treatment is one of the thermal engineering processes, which is used to cool the material from the temperature of −150 °C to −273 °C. This research work utilizes cryogenically treated drill tools for investigating the drilling performance on aluminium alloy (IS737.Gr19000) workpiece material. The independent variables and dependent variables are studied in this experimental analysis are spindle speed, feed rate and machining time, entry and exit burr dimensions, thrust force, torque, Ovality, surface roughness, respectively. The theoretical investigation is also carried out with statistical analysis. The response surface methodology with Box Behnken design the 17 experimental runs with 9 different treated drill tools are carried out. The cryogenically treated drill bit gave good results on burr dimensions, Ovality, surface roughness on drilled hole quality. The tool wear performance was also studied with drill tool geometry measurements with the tool makers microscope. The cryogenically treated drill bits gave the best results than the normal drill bit

The Shallow-Water Crinoid Fauna of Lakshadweep Atolls, North-Western Indian Ocean

A biodiversity survey carried out from 2016 to 2018 by the Department of Science and Technology in the Lakshadweep Atolls, India, recorded six species of shallow-water feather stars new to the archipelago (Comanthus wahlbergii, Comaster schlegelii, Himerometra robustipinna, Dichrometra palmata, Stephanometra indica, and Phanogenia typica). Himerometra sol A.H. Clark, 1912, previously known only from the Maldive Islands, is synonymized under Himerometra robustipinna (Carpenter, 1881). This study brings the total number of shallow-water crinoids recorded from Lakshadweep to ten species. Of the four species collected previously from the archipelago, only Comatella nigra was found in this survey. Of those not collected, Comatella stelligera and Oligometra serripinna are widespread in the Indo-western Pacific region, whereas Heterometra compta is known only from Lakshadweep, and its validity remains uncertain. The known shallow-water crinoid fauna of the archipelago is substantially less diverse than that of the adjacent and environmentally similar Maldive Islands, emphasizing the need for additional research in this island group, in particular, to determine whether the differences are actual or not, and whether they are based on natural conditions versus anthropogenic impacts

Experimental Investigation on Performance of an Arc Transverse Injection in a Supersonic Combustor Flow

The design of a supersonic combustor ramjet engine has gained significant attention for futuristic air-breathing engines. Achieving efficient fuel mixing and complete combustion within a short period poses a substantial challenge. This study has directed efforts towards improving mixing and minimizing total pressure losses across the supersonic combustor to enhance performance. Experiments were conducted to investigate the influence of fuel injection geometry in the supersonic combustor with an entry Mach number of 2. Two different fuel orifice geometries, inclined at 45°, were considered. The investigation covered four different momentum flux ratios: 0.8, 1.0, 1.2, and 1.4 respectively. Various measurements were conducted to observe flow phenomena inside the supersonic combustion, including wall static pressure measurement, Schlieren visualization, exit Mach number and total pressure loss measurement. Without injection cases exhibited weaker compression and expansion inside the combustor. During injection, the rise in wall pressure indicated that the bow shock formed in front of the arc injection was slightly weaker than that of the circular injection. The impinging bow shock on the opposite wall also exhibited higher strength, resulting in a static pressure rise. As a result, the lower total pressure ratio across the shock indicates a higher momentum exchange between the main flow and the orifice. Therefore, arc injection has proven more effective in exchanging momentum inside the supersonic combustor. Consequently, the Mach number at the exit of the combustor was higher for the arc injection

A Combination of Sulindac and Antimicrobial Eradication of H. pylori Prevents Progression of Gastric Cancer in Hypergastrinemic INS-GAS Mice

Author Manuscript: 2010 October 15Helicobacter pylori infection causes severe dysplasia manifested as gastrointestinal intraepithelial neoplasia (GIN) after 28 weeks post–H. pylori infection (WPI) in cancer-prone, hypergastrinemic male INS-GAS mice. We examined the efficacy of the nonsteroidal anti-inflammatory drug sulindac (400 ppm in drinking water) alone, the CCK2/gastrin receptor antagonist YM022 (45 mg/kg/wk) alone, and sulindac or YM022 combined with H. pylori eradication therapy to prevent H. pylori–associated gastric cancer in male INS-GAS mice. Treatments started at 22 WPI, and mice were euthanized at 28 WPI. In uninfected mice, all treatments significantly delayed development of spontaneous GIN (P < 0.05). In H. pylori–infected mice, sulindac alone or YM022 alone had no protective effect on H. pylori–associated GIN. Importantly, sulindac exacerbated the severity of H. pylori–associated gastritis despite decreased gastric prostaglandin E2 levels. However, sulindac combined with H. pylori antimicrobial eradication reduced the incidence of GIN (P < 0.05), whereas YM022 combined with antimicrobial eradication did not reduce GIN. In infected mice, sulindac or YM022 treatment did not alter gastric expression of the proinflammatory cytokines Ifn-γ and Tnf-α and mucosal cell proliferation. Sulindac or YM022 combined with antimicrobial eradication down-regulated mRNA levels of Ifn-γ and Tnf-α and mucosal cell proliferation (P < 0.05). We conclude that sulindac enhances H. pylori gastritis and may promote inflammation-mediated gastric carcinogenesis. The combination of sulindac and antimicrobial H. pylori eradication was beneficial for reducing proinflammatory cytokine mRNA in the stomach and preventing progression from severe dysplasia to gastric cancer in H. pylori–infected INS-GAS mice. [Cancer Res 2009;69(20):8166–74]National Institutes of Health (U.S.) (Grant R01AI37750)National Institutes of Health (U.S.) (Grant P01CA26731)National Institutes of Health (U.S.) (Grant P30ES02109)National Institutes of Health (U.S.) (Grant R01CA093405-07A1

CCK2R identifies and regulates gastric antral stem cell states and carcinogenesis

Objective Progastrin is the incompletely cleaved precursor of gastrin that is secreted by G-cells in the gastric antrum. Both gastrin and progastrin bind to the CCK2 receptor (Cckbr or CCK2R) expressed on a subset of gastric epithelial cells. Little is known about how gastrin peptides and CCK2R regulate gastric stem cells and carcinogenesis. Interconversion among progenitors in the intestine is documented, but the mechanisms by which this occurs are poorly defined. Design We generated CCK2R-CreERT mice and performed inducible lineage tracing experiments. CCK2R+ antral cells and Lgr5+ antral stem cells were cultured in a three-dimensional in vitro system. We crossed progastrin-overexpressing mice with Lgr5-GFP-CreERT mice and examined the role of progastrin and CCK2R in Lgr5+ stem cells during MNU-induced carcinogenesis. Results Through lineage tracing experiments, we found that CCK2R defines antral stem cells at position +4, which overlapped with an Lgr5neg or low cell population but was distinct from typical antral Lgr5high stem cells. Treatment with progastrin interconverts Lgr5neg or low CCK2R+ cells into Lgr5high cells, increases CCK2R+ cell numbers and promotes gland fission and carcinogenesis in response to the chemical carcinogen MNU. Pharmacological inhibition or genetic ablation of CCK2R attenuated progastrin-dependent stem cell expansion and carcinogenesis. Conclusions CCK2R labels +4 antral stem cells that can be activated and expanded by progastrin, thus identifying one hormonal trigger for gastric stem cell interconversion and a potential target for gastric cancer chemoprevention and therapy

Role and promise of health policy and systems research in integrating rehabilitation into the health systems

Despite recognized need and reasonable demand, health systems and rehabilitation communities keep working in silos, independently with minimal recognition to the issues of those who require rehabilitation services. Consolidated effort by health systems and rehabilitation parties, recognizing the value, power and promise of each other, is a need of the hour to address this growing issue of public health importance. In this paper, the importance and the need for integration of rehabilitation into health system is emphasized. The efforts being made to integrate rehabilitation into health systems and the potential challenges in integration of these efforts were discussed. Finally, the strategies and benefits of integrating rehabilitation in health systems worldwide is proposed. Health policy and systems research (HPSR) brings a number of assets that may assist in addressing the obstacles discussed above to universal coverage of rehabilitation. It seeks to understand and improve how societies organize themselves to achieve collective health goals; considers links between health systems and social determinants of health; and how different actors interact in policy and implementation processes. This multidisciplinary lens is essential for evidence and learning that might overcome the obstacles to the provision of rehabilitation services, including integration into health systems. Health systems around the world can no longer afford to ignore rehabilitation needs of their populations and the World Health Assembly (WHA) resolution marked a global call to this effect. Therefore, national governments and global health community must invest in setting a priority research agenda and promote the integration of rehabilitation into health systems. The context-specific, need-based and policy-relevant knowledge about this must be made available globally, especially in low- and middle-income countries. This could help integrate and implement rehabilitation in health systems of countries worldwide and also help achieve the targets of Rehabilitation 2030, universal health coverage and Sustainable Development Goals

Denervation suppresses gastric tumorigenesis

The nervous system plays an important role in the regulation of epithelial homeostasis and has also been postulated to play a role in tumorigenesis. We provide evidence that proper innervation is critical at all stages of gastric tumorigenesis. In three separate mouse models of gastric cancer, surgical or pharmacological denervation of the stomach (bilateral or unilateral truncal vagotomy, or local injection of botulinum toxin type A) markedly reduced tumor incidence and progression, but only in the denervated portion of the stomach. Vagotomy or botulinum toxin type A treatment also enhanced the therapeutic effects of systemic chemotherapy and prolonged survival. Denervation-induced suppression of tumorigenesis was associated with inhibition of Wnt signaling and suppression of stem cell expansion. In gastric organoid cultures, neurons stimulated growth in a Wnt-mediated fashion through cholinergic signaling. Furthermore, pharmacological inhibition or genetic knockout of the muscarinic acetylcholine M[subscript 3] receptor suppressed gastric tumorigenesis. In gastric cancer patients, tumor stage correlated with neural density and activated Wnt signaling, whereas vagotomy reduced the risk of gastric cancer. Together, our findings suggest that vagal innervation contributes to gastric tumorigenesis via M[subscript 3] receptor–mediated Wnt signaling in the stem cells, and that denervation might represent a feasible strategy for the control of gastric cancer

Galaxy and Mass Assembly (GAMA): tracing galaxy environment using the marked correlation function

Context. Galaxies are biased tracers of the underlying network of dark matter. The strength of this bias depends on various galaxy properties, as well as on redshift. One of the methods used to study these dependences of the bias are measurements of galaxy clustering. Such studies are made using galaxy samples from various catalogues – frequently bearing their own problems related to sample selection methods. It is therefore crucial to understand how sample choice influences the clustering measurements, and which galaxy property is the most direct tracer of the galaxy environment. Aims. We investigate how different galaxy properties – luminosities in u, g,r, J, K-bands, stellar mass, star formation rate and specific star formation rate trace the environment in the local universe. We also study the effect of survey flux limits on galaxy clustering measurements. Methods. We measure the two-point correlation function (2pCF) and marked correlation functions (MCFs) using the aforementioned properties as marks. We use nearly stellar-mass-complete galaxy sample in the redshift range 0.1 < z < 0.16 from the Galaxy And Mass Assembly (GAMA) survey with a flux limit of r < 19.8. Further, we impose a brighter flux limit of r < 17.8 to our sample and repeat the measurements to study how this affects galaxy clustering analysis. We compare our results to measurements from the Sloan Digital Sky Survey (SDSS) with flux limits of r < 17.8 and r < 16.8. Results. We show that the stellar mass is the most direct tracer of galaxy environment, the K-band luminosity being a good substitute, although such a proxy sample misses close pairs of evolved, red galaxies. We also show that the u-band luminosity can be a proxy of star formation rate in the context of galaxy clustering. We observe an effect of the survey flux limit on clustering studies – samples with a higher flux limit (smaller magnitude) miss some information about close pairs of starburst galaxies