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71.
Tariq Alkhalifah 《Communications In Computational Physics》2020,28(1):276-296
Recorded seismic data are sensitive to the Earth's elastic properties, and
thus, they carry information of such properties in their waveforms. The sensitivity
of such waveforms to the properties is nonlinear causing all kinds of difficulties to the
inversion of such properties. Inverting directly for the components forming the wave
equation, which includes the wave equation operator (or its perturbation), and the
wavefield, as independent parameters enhances the convexity of the inverse problem.
The optimization in this case is provided by an objective function that maximizes the
data fitting and the wave equation fidelity, simultaneously. To enhance the practicality and efficiency of the optimization, I recast the velocity perturbations as secondary
sources in a modified source function, and invert for the wavefield and the modified
source function, as independent parameters. The optimization in this case corresponds
to a linear problem. The inverted functions can be used directly to extract the velocity
perturbation. Unlike gradient methods, this optimization problem is free of the Born
approximation limitations in the update, including single scattering and cross talk that
may arise for example in the case of multi sources. These specific features are shown
for a simple synthetic example, as well as the Marmousi model. 相似文献
72.
Ann Sofie Olesen Graham J. Belsham Thomas Bruun Rasmussen Louise Lohse Ren Bdker Tariq Halasa Anette Boklund Anette Btner 《Transboundary and Emerging Diseases》2020,67(4):1472-1484
Following its introduction into Georgia in 2007, African swine fever virus (ASFV) has become widespread on the European continent and in Asia. In many cases, the exact route of introduction into domestic pig herds cannot be determined, but most introductions are attributed to indirect virus transmission. In this review, we describe knowledge gained about different matrices that may allow introduction of the virus into pig herds. These matrices include uncooked pig meat, processed pig‐derived products, feed, matrices contaminated with the virus and blood‐feeding invertebrates. Knowledge gaps still exist, and both field studies and laboratory research are needed to enhance understanding of the risks for ASFV introductions, especially via virus‐contaminated materials, including bedding and feed, and via blood‐feeding, flying insects. Knowledge obtained from such studies can be applied to epidemiological risk assessments for the different transmission routes. Such assessments can be utilized to help predict the most effective biosecurity and control strategies. 相似文献
73.
74.
Waleed Hassan AlMalki Imran Shahid Abeer Yousaf Mehdi Muhammad Hassan Hafeez 《Indian journal of pharmacology》2014,46(3):251-256
Angiogenesis is a physiological process which describes the development of new blood vessels from the existing vessels. It is a common and the most important process in the formation and development of blood vessels, so it is supportive in the healing of wounds and granulation of tissues. The different assays for the evaluation of angiogenesis have been described with distinct advantages and some limitations. In order to develop angiogenic and antiangiogenic techniques, continuous efforts have been resulted to give animal models for more quantitative analysis of angiogenesis. Most of the studies on angiogenic inducers and inhibitors rely on various models, both in vitro, in vivo and in ova, as indicators of efficacy. The angiogenesis assays are very much helpful to test efficacy of both pro- and anti- angiogenic agents. The development of non-invasive procedures for quantification of angiogenesis will facilitate this process significantly. The main objective of this review article is to focus on the novel and existing methods of angiogenesis and their quantification techniques. These findings will be helpful to establish the most convenient methods for the detection, quantification of angiogenesis and to develop a novel, well tolerated and cost effective anti-angiogenic treatment in the near future.KEY WORDS: Angiogenesis, angiogenesis assays, quantification techniques 相似文献
75.
Jai Kumar Roha Saeed Memon Izza Shahid Tehlil Rizwan Maryam Zaman Ritesh G. Menezes Sarwan Kumar Tariq Jamal Siddiqi Muhammad Shariq Usman 《Digestive and liver disease》2021,53(1):44-51
BackgroundThe efficacy of antidiabetic agents for the treatment of non-alcoholic fatty liver disease (NAFLD) remains unclear.AimTo conduct a meta-analysis to study the efficacy of pioglitazone and three novel anti-diabetic agents: glucagon-like peptide-1 (GLP-1) agonists, sodium-glucose co-transporter-2 (SGLT2) inhibitors, and dipeptidyl-peptidase-4 (DPP4) inhibitors in treating NAFLD.MethodsOnline databases were searched in May 2020 for randomized clinical trials. Results from random-effects meta-analysis are presented as weighted mean differences (WMDs) or standard mean differences (SMDs) and corresponding 95% confidence intervals (CIs).ResultsTwenty-six studies (n=946 NAFLD patients) were included. Reductions in ALT were seen with all four drugs: pioglitazone (MD -38.41, p<0.001), SGLT2 inhibitors (MD -16.17, p<0.001), GLP-1 agonists (MD -27.98, p=0.04) and DPP-4 inhibitors (MD -7.41, p<0.001). Pioglitazone (SMD -1.01; p<0.001) and GLP-1 agonists (SMD -2.53, p=0.03) also demonstrated significant improvements in liver steatosis. SGLT2 inhibitors (SMD -4.64, p=0.06) and DPP-4 (SMD -2.49, p=0.06) inhibitors trended towards reduced steatosis; however, these results were non-significant.ConclusionPioglitazone demonstrates significant improvements in transaminases and liver histology in both diabetic and non-diabetic NAFLD patients. Early evidence from diabetic NAFLD patients suggests that novel antidiabetics may lead to improvements in liver enzymes and hepatic steatosis, and this should encourage further research into possible utility of these drugs in treating NAFLD. 相似文献
76.
Low cost adsorbents such as P. australis have received considerable interest owing to their low cost and easy availability. The aim of the present study was the evaluation of the removal of chemical oxygen demand (COD), biological oxygen demand (BOD), total suspended and dissolved solids (TSS and TDS) using dried P. australis in influent wastewater to a wastewater treatment plant. The results of the COD and BOD concentration reduction with P. australis at optimum operating conditions were determined for maximum reduction and adsorption isotherms. The maximum reduction of COD, BOD, TSS and TDS concentrations under the optimum operating conditions was 92.27%, 93.89%, 94.38% and 91.61%, respectively. The results demonstrate that the new dried biosorbent is able to adsorb all the aforementioned contamination. It achieved an adsorption capacity for COD of 72.5 mg g−1 and an adsorption capacity for BOD of 43.93 mg g−1. The results were well fitted by the pseudo-second order model with R2 = 0.984.Low cost adsorbents such as P. australis have received considerable interest owing to their low cost, large amount of functional groups and easy availability. 相似文献
77.
Mohamed H. Zeitoun Ali A. Abdel-Rahim Mahmoud M. Hasanin Abeer S. El Hadidi Wafaa A. Shahin 《Diabetes & Metabolic Syndrome: Clinical Research & Reviews》2021,15(3):711-718
BackgroundHyperglycemia in acute coronary syndrome (ACS) is linked to raised morbidity and mortality. Insulin administration using insulin infusion protocols (IIP) is the preferred strategy to control hyperglycemia in critically ill patients. To date, no specific IIP has been identified as the most efficient for achieving glycemic control.Aimto compare glycemic achievements (safety) (primary objective), and coronary and other clinical outcomes (efficacy) (secondary objective) by hyperglycemia management in Cardiac Care Unit (CCU) using computerized Atlanta Protocol (Group (I)) versus paper-based Joint British Diabetes Societies (JBDS) For Inpatient Care Protocol (Group (II)).Patients and methodsThe study was done on 100 ACS patients admitted to Alexandria Main University hospital CCU with RBG >180 mg/dL. They were randomized into the 2 groups in a 1:1 ratio. CBG was measured hourly for 72 hours and was managed by IV insulin infusion.ResultsGroup (I) showed statistically significant less mean time for target BG achievement (3.52 ± 1.53hours), lower incidence of Level 1 hypoglycemia (2%) than Group (II) (4.76 ± 2.33 hours, 22%, p = 0.013, 0.002 respectively) and statistically significant less mean number of episodes above the glycemic target after its achievement than Group (II) (p < 0.001). Regarding Level 2 hypoglycemia the difference was not significant statistically.ConclusionBoth protocols successfully maintained target BG level with low incidence of clinically significant hypoglycemia, however, the computerized Atlanta protocol achieved better glycemic outcomes. We recommend the use of the computerized Atlanta protocol in CCU rather than JBDS for Inpatient Care Protocol whenever this is feasible. 相似文献
78.
Ahmed Abeer Ahmed Qaed McKay Tracey Jill Morton 《Proceedings of the National Academy of Sciences, India. Section B.》2019,89(2):441-447
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Ligninolytic bacteria are considered a major source of ligninolytic enzymes, which are widely used in a... 相似文献
79.
80.
Peretz Resnitzky Estela Matutes Michael Hedges Ricardo Morilla Vasantha Brito-Babapulle Tariq Khokhar & Daniel Catovsky 《British journal of haematology》1966,94(2):352-361
We conducted an ultrastructural study in 22 cases of B-lymphoproliferative disorders in leukaemic phase bearing the t(11;14) translocation. The features of peripheral blood leukaemic cells in nine cases of mantle cell lymphoma (MCL) were compared to those diagnosed as B-prolymphocytic leukaemia (B-PLL) (five cases), splenic lymphoma with villous lymphocytes (SLVL) (four cases), lymphoplasmocytic lymphoma (LPL) (one case), chronic lymphocytic leukaemia with >10% prolymphocytes (CLL/PL) (one case) and unclassified B-non Hodgkin's lymphoma (B-NHL) (two cases). The ultrastructural characteristics were also compared to those present in B-NHL without t(11;14), including cases of follicular centre lymphoma (FCL). This study shows that MCL has distinct ultrastructural features including a cleaved or indented nucleus with an even heterochromatin distribution, an absent or inconspicuous nucleolus, low N/C ratio, abundant mitochondria, a well developed Golgi zone, profiles of endoplasmic reticulum and centrioles. This pattern clearly differs from that found in FCL cells. The nuclear pattern of MCL cells also differed from the cells in the other disorders with t(11;14), but shared an organelle-rich cytoplasm, and features which were not apparent in cases without t(11;14). The cytoplasmic changes observed in cells bearing t(11;14) suggest increased cellular activity which may relate to the chromosome translocation and the resulting over-expression of bcl-1. 相似文献