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Analysis of the dielectric properties of R410A Gas as an alternative to SF_(6)for high-voltage applications

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High Voltage 2019年第1期4卷 41-48页

作者： Bakhtiar Khan Jawad Saleem Faisal Khan Gul Faraz rizwan ahmad Naveed Ur Rehman Zahoor ahmad Department of Electrical Engineering COMSATS University IslamabadAbbottabad CamusPakistan

Electric power industry is extensively using gas-insulated systems for the transmission and distribution of electrical *** high-voltage technology,the gas insulation is dominated by Sulphur-hexafluoride(SF_(6))since the early *** is a greenhouse gas and has long atmospheric *** paper proposes comparatively more environmental friendly R410 gas as an alternative to SF_(6)for high-voltage *** validate the performance and theoretical concepts,it has been analysed *** gases air and carbon dioxide were mixed with the base gas R410A to reduce the liquification temperature and global warming *** strength of R410A was tested for DC as well as AC voltage,results were compared with that of SF_(6)and other alternatives available in literature,and the results were *** self-recoverability test of R410A was performed and the synergistic effect of the mixed gases was ***,this work has discovered that R410A is the suitable alternative to SF_(6)for high-voltage applications.

关键词： R410A gases high

A low complexity online controller using fuzzy logic in energy harvesting WSNs

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Science China(Information Sciences) 2019年第4期62卷 167-176页

作者： Talha AZFAR Waqas AHMED Abdul HASEEB rizwan ahmad Sufi Tabassum GUL Fu-Chun ZHENG Department of Electrical Engineering Pakistan Institute of Engineering and Applied Sciences (PIEAS) School of Electrical Engineering and Computer Science National University of Sciences and Technology (NUST) School of Electronic and Information Engineering Harbin Institute of Technology

In this paper, we present a fuzzy logic based scheme for a two hop energy harvesting(EH)wireless sensor network(WSN). Incorporating data and energy causality constraints, discrete transmission rates, finite energy and data buffers, a fuzzy model is developed which uses network throughput, battery level and channel gain as inputs. The fuzzy scheme is then compared with optimum, modified optimum, and Markov decision process(MDP) schemes in terms of computational complexity, throughput, battery level and data buffer capacity. The throughput results show that the fuzzy online scheme preforms closely to the compared schemes and avoids battery depletion even when the number of discrete transmission rates are increased.

关键词： wireless sensor networks energy harvesting cooperative communications fuzzy logic

Persistent port-site sinus in a patient after laparoscopic cholecystectomy:watch out for gallbladder tuberculosis

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Hepatobiliary & Pancreatic Diseases International 2011年第3期10卷 328-329页

作者： Tariq Mansoor Syed Amjad Ali Rizvi rizwan ahmad Khan Department of Surgery Jawaharlal Nehru Medical College HospitalAligarh Muslim University

BACKGROUND:The gallbladder is rarely affected by mycobacterium *** diagnosis of gallbladder tuberculosis is often not suspected prior to surgery or ***:A young female patient underwent laparoscopic cholecystectomy but presented with a persistently discharging sinus from the port ***:The gallbladder biopsy revealed granulomas typical of chronic granulomatous *** condition of the patient was improved by antitubercular ***:Presentation of gallbladder tuberculosis as a persistent discharging sinus at the port site in a patient who has undergone a laparoscopic cholecystectomy is extremely *** diagnosis was reached by histopathology *** rarity of the presentation prompted us to report the case.

关键词： port-site sinus laparoscopic cholecystectomy gallbladder tuberculosis

Anti-infective, cytotoxic and antioxidant activity of Ziziphus oxyphylla and Cedrela serrata

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Asian Pacific Journal of Tropical Biomedicine 2016年第8期6卷 671-676页

作者： rizwan ahmad Niyaz ahmad Atta Abbas Naqvi Paul Cos Louis Maes Sandra Apers Nina Hermans Luc Pieters Natural Products and Alternative Medicine College of Clinical Pharmacy University of Dammam Department of Pharmaceutics College of Clinical Pharmacy University of Dammam Department of Pharmacy Practice College of Clinical Pharmacy University of Dammam Faculty of Pharmaceutical Biomedical and Veterinary Sciences Laboratory of Microbiology Parasitology and Hygiene (LMPH) University of Antwerp Faculty of Pharmaceutical Biomedical and Veterinary Sciences Natural Products & Food–Research and Analysis (NatuRA)University of Antwerp

Objective: To search for the most active antimicrobial and antioxidant sub-fractions related to traditional use of Ziziphus oxyphylla(Z. oxyphylla) and Cedrela serrata(C. serrata) in Pakistan against infectious and liver ***: Factions of different polarity were tested in vitro for their antiprotozoal,antimalarial, antibacterial and antifungal activity against different pathogens. Cytotoxicity on MRC-5 cell lines(human lung fibroblasts) as well as, in vitro radical scavenging activity was evaluated using the 1, 1-diphenyl-2-picrylhydrazyl radical ***: The highest antiprotozoal activity was observed for the CHCl3 fractions of Z. oxyphylla roots and leaves, and C. serrata bark. The CHCl3 and Et OAc fractions of Z. oxyphylla roots, the CHCl3 fraction of Z. oxyphylla leaves, the Et OAc and the residual Me OH: H2 O fraction of C. serrata bark showed antibacterial activity against Staphylococcus aureus. The same residual Me OH: H2 O fraction of C. serrata bark was active against Candida albicans. The highest antioxidant activity was observed for the more hydrophilic Et OAc fractions of Z. oxyphylla leaves, C. serrata bark and leaves, and the residual Me OH: H2 O fraction of C. serrata ***: This study supports at least in part the traditional uses of these plants for antimicrobial purposes and against liver diseases.

关键词： Antifungal Antibacterial Antiprotozoal Cytotoxicity Antioxidant Ziziphus oxyphylla Cedrela serrata Rhamnaceae Meliaceae Pakistan

Mucosal healing and inflammatory bowel disease:Therapeutic implications and new targets

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World Journal of Gastroenterology 2023年第7期29卷 1157-1172页

作者： Megan Lynn Otte Raju Lama Tamang Julia Papapanagiotou rizwan ahmad Punita Dhawan Amar B Singh Department of Pathology and Microbiology University of Nebraska Medical CenterOmahaNE 68198United States Department of Biochemistry and Molecular Biology University of Nebraska Medical CenterOmahaNE 68198United States

Mucosal healing(MH)is vital in maintaining homeostasis within the gut and protecting against injury and *** factors and signaling pathways contribute in a dynamic and coordinated manner to maintain intestinal homeostasis and mucosal regeneration/***,when intestinal homeostasis becomes chronically disturbed and an inflammatory immune response is constitutively active due to impairment of the intestinal epithelial barrier autoimmune disease results,particularly inflammatory bowel disease(IBD).Many proteins and signaling pathways become dysregulated or impaired during these pathological conditions,with the mechanisms of regulation just beginning to be ***,there remains a relative lack of broadly effective therapeutics that can restore MH due to the complexity of both the disease and healing processes,so tissue damage in the gastrointestinal tract of patients,even those in clinical remission,*** increased understanding of the molecular mechanisms of IBD and MH,tissue damage from autoimmune disease may in the future be ameliorated by developing therapeutics that enhance the body’s own healing *** this review,we introduce the concept of mucosal healing and its relevance in IBD as well as discuss the mechanisms of IBD and potential strategies for altering these processes and inducing MH.

关键词： Inflammation Injury/repair Mucosal healing Mucosal barrier Therapeutics Colitis

Dual autoimmune diseases:Rheumatoid arthritis with systemic lupus erythematosus and Type 1 diabetes mellitus with multiple sclerosis

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Rheumatology & Autoimmunity 2022年第3期2卷 120-128页

作者： rizwan ahmad Haseeb Ahsan College of Medicine Imam Abdulrahman bin Faisal UniversityDammamSaudi Arabia Department of Biochemistry Faculty of DentistryJamia Millia Islamia(A Central University)New DelhiIndia

Autoantibodies and inflammation are the hallmarks of autoimmune diseases(ADs).Organ-specific and nonorgan-specific ADs are divided according to whether the autoimmune reaction is directed against a specific tissue(e.g.,thyroid in Hashimoto's thyroiditis)or widely expressed antigens(e.g.,cell nuclei in systemic lupus erythematosus[SLE]).SLE is distinguished by the presence of circulating autoantibodies and immune complex deposition,both of which can induce inflammatory damage to many *** arthritis(RA),sometimes called inflammatory arthritis,is a systemic AD that affects the joints and causes *** sclerosis(MS)is a central nervous system inflammatory disease with various neurological and autoimmune *** have been reported between RA and SLE as well as between Type 1 diabetes mellitus and *** of shared genes and biological processes could aid in the discovery of possible treatment targets in these dual *** review article explores the molecular nature and familial inheritance of dual ADs.

关键词： autoantibodies autoimmune diseases autoimmunity multiple sclerosis rheumatoid arthritis rhupus systemic lupus erythematosus Type 1 diabetes mellitus

Oxidative Cascade Prognosis, Antioxidants &Selected Trace Elements in COVID-19

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Open Journal of Applied Sciences 2020年第11期10卷 688-700页

作者： rizwan ahmad Ansari Karimah Mohammed Rabiu Department of Biochemistry Yobe State University Damaturu Nigeria Department of Biological Sciences Yobe State University Damaturu Nigeria

COVID-19 pandemic has now become a challenging global public health concern, having higher risk of developing fatal respiratory disease due to severe inflammatory responses associated with the virus-mediated oxidative stress. The respiratory system is most preferred target organ for this novel virus as the lung is well oxygenated and having large surface area available to the virus for exposure and successively augmenting the health complications. Oxidative stress (OS) is an important factor causing metabolic and physiological alteration and various disease augmentations within the body. Respiratory viral infection has general consociation with cytokine production, inflammation, cell death and other pathophysiological processes which may be the result of perturbed redox balance. Apart from this, the presence of conditions likes aging, diabetes and hypertension and chronic obstructive pulmonary diseases (COPD) are the risk factor for making severity of such infection outcome. It has been well established that an overproduction of reactive oxygen species (ROS) and antioxidant mechanisms deprivation are vital step for viral replica production and consequent release of pro-inflammatory cytokines is also an important factor of the innate immune responses to the pathogens that may result into acute lung damage. Additionally, ROS can damage various vital biological molecules and inactivation of essential enzymes. Oxidative stress is an important factor causing metabolic and other pathophysiological alterations, such as protein oxidations and various associated diseases. Therefore, in this paper, the significant adverse impact of virus on host

关键词： COVID-19 COPD ROS Oxidative Stress Cytokines Inflammation

Fabrication of Underwater Superoleophobic Membranes for Oil/Water Separation

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Fabrication of Underwater Superoleophobic Membranes for Oil/...

作者： rizwan ahmad 西北师范大学

学位级别：硕士

环境问题是当前人类所面临的巨大挑战。雾霾、污水、固体废弃物以及排放物污染严重地威胁着自然环境和人类健康。其中每一个问题都是人类社会本身发展中所出现的副产物,而解决这些问题也需要科技工作者付出巨大的努力。由原油泄漏、航... 详细信息

环境问题是当前人类所面临的巨大挑战。雾霾、污水、固体废弃物以及排放物污染严重地威胁着自然环境和人类健康。其中每一个问题都是人类社会本身发展中所出现的副产物,而解决这些问题也需要科技工作者付出巨大的努力。由原油泄漏、航海中的油泄露以及污水排放引起的含油污水对于环境造成的污染尤其很大。研究表明,在世界上每年有32亿吨的油分别通过含油废水、化学工业、冶金工业、烟囱、生活废水、机械制造和食品工业等渠道排放到水中,致使油直接接触水而形成污染。在本论文中,我们用三种不同方法制备网膜进行油水分离的测试。它们分别是涂有二氧化钛的滤纸膜、用烟蒂聚合物通过静电纺丝制备的油下超疏水以及水下超疏油网膜和涂有松塔粉末生物质材料的滤纸膜。本论文首先介绍涂有二氧化钛的滤纸膜,该滤膜具有超亲水性和水下超疏油的性质,并且能够有效分离油水混合物。这种滤膜之所以分开油水混合物,是由其超疏水性能决定的,分离过程由重力驱动。在制备滤膜的过程中,我们将二氧化钛纳米颗粒和海藻酸钠的混合物在真空设备下抽滤沉积形成膜层。该滤膜对油水混合物的分离效率都大于99.0%,并且体现出了很好的循环性。与此同时,它还能分开水包油的乳液。这种滤膜将会在大规模的油水分离中体现出良好的应用前景。在油水混合物的分离中,良好的分离效率和持续的渗透力对其尤为重要。而我们在不进行任何化学修饰的情况下,用烟蒂聚合物和二氧化硅粉末的混合物通过静电纺丝法制成了油下超疏水/水下超疏油的不锈钢网膜,并且首次将其运用到油水分离之中。静电纺丝法是一种低成本、可持续的以及可升级制造的新技术,它可以进一步被运用于自然或人工合成的聚合物、含碳聚合物和金属氧化物的混合溶液纺造,以形成微纳米纤维。这种静电纺丝膜对多种油水混合物的分离效率皆高达99%以上。在第三个实验中,我们将松塔粉末的生物质材料和水性聚氨酯通过真空设备沉积在滤纸上形成超亲水/水下超疏油的滤膜。这种喷涂有生物质材料的滤膜具有很好亲水性和水下超疏油性能。在油水分离过程中,水能够流过滤膜而油被截留在上面。这种方法是生态友好、低成本、无毒以及节约时间的一种新方法,油水分离过程中由重力提供驱动力并且分离效率可高达99%。

关键词：水下超疏油油水分离接触角喷涂网膜

Antenatal Sonographic Diagnosis of A Case of Alobar Holoprosencephaly: A Case Report

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International Journal of Clinical Medicine 2012年第5期3卷 431-432页

作者： rizwan ahmad Khan Manjari Thapa Shagufta Wahab Deptt. of Radiodiagnosis JNMCH Aligarh India Deptt. of Radiodiagnosis JNMCH AMUAligarh India Division of Pediatric Sugery Deptt of Surgery JNMCH AMUAligarh

Holoprosencephaly is a rare congenital brain malformation resulting from failure of diverticulation and cleavage of primitive prosencephalon which occurs at 4 - 8th week of gestation and is usually associated with multiple midline facial anomalies. Herein we report an antenatal case of such patient. Patient was evaluated and because of the magnitude of the problem induction was done which led to a still born baby.

关键词： Holoprosencephaly Alobar Antenatal Detection Developing Countries Prognosis