2,023 research outputs found

    Influence of lead Inorganic Compounds on Combustion Rate of Double Base Rocket Propellants

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    The influence of lead nitrate, red lead, lead chromate, lead floride and lead carbonate on the combustion behaviour of double base propellants in the pressure range-35-140kg/cm /sup 2/ was studied. While all these compounds increased burning rates in lower pressure range (35-60 kg/cm/sup 2/) and higher pressure range (120-140 kg/cm/sup 2/), only lead chromate and lead fluoride were effective in the intermediate pressure range of 60-105 kg/cm/sup 2/. None of these compounds were effective as platonizer, except lead fluoride, which lowered n value to 0.34 in the lower pressure range. Addition of carbon black along with lead compounds raised burning rates further and reduced n values significantly in the higher pressure regins. A probable mechanism on the role of lead compounds studied has been suggested based on burning rate and DTA results

    A Review of the Influence of Initial State Shear (K\u3csub\u3eα\u3c/sub\u3e) and Confining Stress (K\u3csub\u3eσ\u3c/sub\u3e) On Failure Mechanisms and Earthquake Liquefaction of Soils

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    Geotechnical engineering profession has continued to use the in situ measurement based empirical procedure to perform soil liquefaction analysis. This method was initially developed based on past earthquake performance of level ground sites. For sloping ground and larger depths or confining stress, the method requires appropriate corrections such as Kα for initial static shear and Kσ for confining stress. The recommended correction factors in the current state of practice have been presented by NCEER (National Center for Earthquake Engineering and Research). These recommendations, however, do not distinguish between the distinct shear behavior of soils on the opposite sides of the critical state line. These factors can significantly influence the results and alter the final conclusion and outcome of an analysis. This paper reviews the existing soil liquefaction research data focusing on these factors based on the critical state soil mechanics framework. It is shown that the undrained response of soils with stable yielding during both monotonic and cyclic loading can be correlated with the distance of the initial state from the critical state line. Kα and Kσ are shown to correlate well with this distance. Constant cyclic resistance ratio lines are found to lie parallel to lines of constant initial state. Furthermore, Kσ variation is found to be material specific

    Fishable concentrations of fishes and crustaceans in the offshore and deep sea areas of the Indian Exclusive Economic Zone based on observations made onboard FORV Sagar Sampada

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    Bottom trawling data of FORV Sagar Sampada pertaining to a total of 350 fishing hauls with a duration of 330 effective trawling hours for depths beyond 40 m was utilized in the present study. Abundance of selected fishery resources such as threadfin bream, bull's eye, drift fish, lizard fish, ribbon fish, cat fish, barracudas, mackerel, deep sea prawns and deep sea lobster in the offshore and deep sea waters of the Indian EEZ in space and time is indicated

    A systematic review of cost-effectiveness studies comparing conventional, biological and surgical interventions for inflammatory bowel disease.

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    Inflammatory bowel disease (IBD) is a chronic disease placing a large health and economic burden on health systems worldwide. The treatment landscape is complex with multiple strategies to induce and maintain remission while avoiding long-term complications. The extent to which rising treatment costs, due to expensive biologic agents, are offset by improved outcomes and fewer hospitalisations and surgeries needs to be evaluated. This systematic review aimed to assess the cost-effectiveness of treatment strategies for IBD. A systematic literature search was performed in March 2017 to identify economic evaluations of pharmacological and surgical interventions, for adults diagnosed with Crohn's disease (CD) or ulcerative colitis (UC). Costs and incremental cost-effectiveness ratios (ICERs) were adjusted to reflect 2015 purchasing power parity (PPP). Risk of bias assessments and a narrative synthesis of individual study findings are presented. Forty-nine articles were included; 24 on CD and 25 on UC. Infliximab and adalimumab induction and maintenance treatments were cost-effective compared to standard care in patients with moderate or severe CD; however, in patients with conventional-drug refractory CD, fistulising CD and for maintenance of surgically-induced remission ICERs were above acceptable cost-effectiveness thresholds. In mild UC, induction of remission using high dose mesalazine was dominant compared to standard dose. In UC refractory to conventional treatments, infliximab and adalimumab induction and maintenance treatment were not cost-effective compared to standard care; however, ICERs for treatment with vedolizumab and surgery were favourable. We found that, in general, while biologic agents helped improve outcomes, they incurred high costs and therefore were not cost-effective, particularly for use as maintenance therapy. The cost-effectiveness of biologic agents may improve as market prices fall and with the introduction of biosimilars. Future research should identify optimal treatment strategies reflecting routine clinical practice, incorporate indirect costs and evaluate lifetime costs and benefits

    Retrospective CT/MRI Texture Analysis of Rapidly Progressive Hepatocellular Carcinoma

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    Rapidly progressive hepatocellular carcinoma (RPHCC) is a subset of hepatocellular carcinoma that demonstrates accelerated growth, and the radiographic features of RPHCC versus non-RPHCC have not been determined. The purpose of this retrospective study was to use baseline radiologic features and texture analysis for the accurate detection of RPHCC and subsequent improvement of clinical outcomes. We conducted a qualitative visual analysis and texture analysis, which selectively extracted and enhanced imaging features of different sizes and intensity variation including mean gray-level intensity (mean), standard deviation (SD), entropy, mean of the positive pixels (MPP), skewness, and kurtosis at each spatial scaling factor (SSF) value of RPHCC and non-RPHCC tumors in a computed tomography (CT) cohort of n = 11 RPHCC and n = 11 non-RPHCC and a magnetic resonance imaging (MRI) cohort of n = 13 RPHCC and n = 10 non-RPHCC. There was a statistically significant difference across visual CT irregular margins p = 0.030 and CT texture features in SSF between RPHCC and non-RPHCC for SSF-6, coarse-texture scale, mean p = 0.023, SD p = 0.053, MPP p = 0.023. A composite score of mean SSF-6 binarized + SD SSF-6 binarized + MPP SSF-6 binarized + irregular margins was significantly different between RPHCC and non-RPHCC (p = 0.001). A composite score ≥3 identified RPHCC with a sensitivity of 81.8% and specificity of 81.8% (AUC = 0.884, p = 0.002). CT coarse-texture-scale features in combination with visually detected irregular margins were able to statistically differentiate between RPHCC and non-RPHCC. By developing an image-based, non-invasive diagnostic criterion, we created a composite score that can identify RPHCC patients at their early stages when they are still eligible for transplantation, improving the clinical course of patient care

    Abnormal hermaphroditic skipjack, Katsuwonus pelamis (Linnaeus, 1758) from Agatti coast, Lakshadweep, India

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    A hermaphroditic specimen of skipjack tuna, Katsuwonus pelamis of forklength (FL) – 56 cm and total weight (TW) – 3.20 kg was caught by pole and line on 21st November 2005 from the Agatti coast, Lakshadweep. Histological studies revealed that both the ovarian and testicular portions had developed a complete series of gametogenic cell lines

    Long-term persistence of cellular hyporesponsiveness to filarial antigens after clearance microfilaraemia

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    The persistence of parasite-specific cellular hyporesponsiveness after clearance of blood microfilariae (mf) was studied in 18 individuals who had been treated with a single dose of ivermectin, diethylcarbamazine, or a combination 2-3 years previously and who had initially cleared their parasitemia. At recruitment into the present study, 50% were again mf+ and 50% remained mf-. There were no significant differences between the mf+ and mf- groups in the amount of interferon- g (IFN- g) produced by peripheral blood mononuclear cells in response to adult or microfilarial antigens, although IFN- g production in response to purified protein derivative was greater in the mf+ group (geometric mean [gm] = 3,791 pg/ml; P = 0.02) than in the mf- group (gm = 600 pg/ml). These data suggest that although microfilaremic individuals may temporarily regain the ability to produce IFN- g to parasite antigens post-treatment, they subsequently revert to a state of hyporesponsiveness to mf-containing antigens that appears to be independent of the recurrence of microfilaremia and the response to nonparasite antigens

    Physiological profile of undifferentiated bovine blastocyst-derived trophoblasts.

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    Made available in DSpace on 2019-12-30T18:09:36Z (GMT). No. of bitstreams: 1 BiolOpenLGustavoSiqPhysiologicalbio037937.full.pdf: 3976442 bytes, checksum: 59f47a5f3c977902a68f8d5bf4d04569 (MD5) Previous issue date: 2019bitstream/item/207915/1/BiolOpen-LGustavoSiq-Physiological-bio037937.full.pd
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