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Before the Jury Is out on Cinacalcet’s Cardiovascular Effects in Hemodialysis Patients: Is Troponin a Missing Link?

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Open Journal of Nephrology 2014年第1期4卷 47-53页

作者： Samra Abouchacra Ahmed Chaaban mohammad budruddin Fares Chedid Mohamad Hakim Mohamad Ahmed Nicole Gebran Farida Marzouki Muhy Eddin Hassan Faiz Al Abbacheyi Department of Medicine Tawam Hospital Abu Dhabi UAE Department of Pediatrics Tawam Hospital Abu Dhabi UAE Department of Pharmacology Tawam Hospital Abu Dhabi UAE SEHA Dialysis Services Tawam Hospital Abu Dhabi UAE

Raised levels of the cardiac biomarker, Troponin I, are frequently encountered in hemodialysis patients and appear to be prognostic indicators for cardiovascular risk. Though evidence suggests that control of secondary hyperparathyroidism may reduce cardiac endpoints, the effect of the calcimimetic agent, cinacalcet, remains controversial. This retrospective study aimed at evaluating troponin levels in hemodialysis patients with severe secondary hyper parathyroidism (SHPT) who are on cinacalcet vs controls on conventional treatment. In addition, clinical outcomes including all-cause, cardiovascular morbidity and mortality were compared among both groups. A decline in Troponin I levels was observed in the cinacalcet group, this however was not translated clinically into improved survival. In fact, all-cause and cardiac mortality was similar in the two groups. Conversely, comparison of the incidence of cardiovascular events revealed lower rates in the cinacalcet group including cardiac, cerebral and peripheral vascular complications. Given some of our study limitations, further long-term, placebo-controlled trials are necessary to definitively establish the effect of cinacalet on cardiac biomarkers and ultimately its impact on clinical outcomes.

关键词： Calcimimetics Secondary Hyperparathyroidism Parathyroid Hormone Cinacalcet Chronic Kidney Disease Cardio Vascular Disease End Stage Renal Disease Troponin I C-Reactive Protein Parathyroidectomy Acute Coronary Syndrome Peripheral Vascular Disease Atherogenesis Myocardial Infraction

Patients Returning to Dialysis after Failed Kidney Transplant: How Do They Fare? A Gulf Perspective

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Open Journal of Internal Medicine 2014年第3期4卷 82-86页

作者： Samra Abouchacra Ahmed Chaaban Abdelkarim Saleh Muna Rukhaimi Osman Furaih Naveed Haq Mohamed Osman Nicole Gebran Qutaiba Hussain Fares Chedid mohammad budruddin Suad Sajwani Department of Nephrology Dubai Hospital Dubai UAE Department of Nephrology King Faisal Specialist Hospital and Research Center Riyadh KSA Department of Nephrology Sheikh Khalifa Medical City Abu Dhabi UAE Department of Nephrology Tawam Hospital Al Ain UAE

An increasing number of failed transplant patients returning to dialysis (FTRD) have been observed with reported worse survival compared to transplant-naive dialysis (TxN) patients. This study aimed to assess outcomes of FTRD vs. matched TxN controls in a Gulf region multi-center trial of 800 HD patients. Similar mortality was seen, likely due to earlier start and better HD adequacy in FTRD. Younger age, less diabetes and living donor transplantation in majority with 27% graft nephrectomy (Nx) might also confer benefits. Subgroup analysis of Nx patients showed more hospitalizations and prior rejection episodes with lower graft survival. The deaths, however, oc-curred only in nonNx group and are likely explained by older age, longer duration on HD, more prevalence of diabetes and CAD. FTRD showed similar survival to TxN. Early intensive HD might account for the benefit. Whether Nx confers advantage is unclear because of the small sample size.

关键词： Renal Transplant Graft Nephrectomy Hemodialysis Dialysis Transplant-Naive Patients End Stage Renal Disease ESRD

Auto-tuning PVT data using multi-objective optimization: Application of NSGA-Ⅱ algorithm

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Petroleum 2024年第1期10卷 135-149页

作者： Abdolhadi Zarifi mohammad Madani mohammad Jafarzadegan Reservoir Engineering Systems Petroleum Engineering Department Main Office Building of National Iranian South Oil Company (NISOC) Combined Planning Management National Iranian Oil Company (NIOC) Reservoir Engineering Division Petroleum Engineering Department Petroleum Engineering and Development Company (PEDEC)

Reservoir simulation is known as perhaps the most widely used, accurate, and reliable method for field development in the petroleum industry. An integral part of a reliable reservoir simulation process is to consider robust and rigorous tuned EOS models. Traditionally, EOS models are tuned iteratively through arduous workflows against experimental PVT data. However, this comes with a number of drawbacks such as forcingly using weight factors, which upon alteration adversely affects the optimization *** objective of the current work is thus to introduce an auto-tune PVT matching tool using NSGA-II multi-objective optimization. In order to illustrate the robustness of the presented technique, three different PVT samples are used, including two black-oil and one gas condensate sample. We utilize PengRobinson EOS during all the manual and auto-tuning processes. Comparison of auto-tuned EOS-generated results with those of experimental and computed statistical error values for these samples clearly show that the proposed method is robust. In addition, the proposed method, contrary to the manual matching process, provides the engineer with several matched solutions, which allows them to select a match based on the engineering background to be best amenable to the problem at hand. In addition, the proposed technique is fast, and can output several solutions within less time compared to the traditional manual matching method.

关键词： Auto-tuning PVT Equation of state NSGA-II Multi-objective optimization

Experience with Post Transplant Parathyroidectomy in Gulf Region and Literature Review

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Open Journal of Nephrology 2013年第4期3卷 211-216页

作者： Samra Abouchacra Ahmed Chaaban Ammar Abdel Baki Khalid Al Mashari Saif Al Sobhi Atia Al Zahrani Qutaiba Hussain Nicole Gebran Mohamed Ahmed Imran Khan Bassam Bernieh mohammad budruddin Armed Forces Hospital Taif KSA King Faisal Specialist Hospital Research Centre (KFSHRC) Riyadh KSA Sheikh Khalifa Medical City (SKMC) Abu Dhabi UAE Tawam Hospital Al Ain UAE

Sustained elevation of parathyroid hormone (PTH) levels is not uncommon post renal transplantation. Though in the majority of patients, it gradually normalizes, on average 5% of transplanted patients require parathyroidectomy (PTX). However, PTX itself has been associated with deterioration in allograft function and even completes graft loss seen with both total and subtotal PTX as well as an increased rate of acute rejection. The aim of this study was to determine the effect of post transplant partial PTX on allograft function in our patients as well as the incidence of acute rejection. Our results show that post transplantation, subtotal PTX, was successful in achieving metabolic control while preserving graft function without an increased incidence of acute rejection. Retention of sufficient residual parathyroid tissue with partial PTX might account for favorable outcome in our study. Despite this, surgery for advanced hyperparathyroidism should optimally take place in the pre-transplant period.

关键词： Parathyroidectomy Renal Transplantation Parathyroid Hormone Hyperparathyroidism

Investigation of material composition,design,and performance of open-graded asphalt mixtures for semi-flexible pavement:A comprehensive experimental study

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第1期11卷 92-116页

作者： mohammad Taghipoor Abolfazl Hassani mohammad M.Karimi Department of Civil and Environmental Engineering Tarbiat Modares UniversityTehranIran

The primary goal of this study is the design and construction of semi-flexible pavement(SFP)mixture in accordance with the engineering and mechanical *** study involves the use of a range of gradation curves,air void contents,cellulose and synthesized fibers,and neat and modified asphalt binders to prepare the open-graded asphalt(OGA)*** analyze the characteristics of these mixtures,a variety of test,namely binder drainage,semi-circular bending(SCB),Cantabro,wheel tracking,indirect tensile strength(ITS),and permeability tests were ***,to analyze the prepared grouting material,flexural strength,compressive strength,and fluidity tests were *** the final stage,SFP was compared to HMA in terms of engineering characteristics and *** to the results,SFP was more resistant to skid,rutting,fire,and moisture damage,while HMA had a better performance in fracture tests,including SCB *** to the results of the mechanical performance tests conducted on OGA mixtures,the highest and lowest values for air void content to achieve the highest mechanical performance level were 30%-35%and 25%,***,based on the laboratory results,it was determined that the required void ratio for constructing OGA mixtures was 24%-26%based on the bitumen type and fibers amount in the ***,SFP mixture can be regarded as a viable alternative to common pavements thanks to its high resistance to rutting and moisture damage,long freezing-thawing fatigue life,and adequate fire and skid resistance.

关键词： Semi-flexible pavement mixture Open-graded asphalt mixture Engineering properties Cantabro test Hot mix asphalt

Recent Progress in Bionic Hydrogels for Articular Cartilage:Tribological and Mechanical Characteristics

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Journal of Bionic Engineering 2024年第2期21卷 653-673页

作者： mohammad Javan Almasi Dangsheng Xiong School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing210094China

Cartilage regeneration and repair are considered clinical challenges since cartilage has limited capability for *** tissue-engineered materials have the ability to repair cartilage,they have weak mechanical characteristics and cannot resist long-term *** the other hand,surgery to replace the joint is frequently done to treat significant cartilage deterioration these ***,the materials that are being used for replacement have high friction coefficients,lack shock absorption functions,and lack *** research on natural articular cartilage structure and function may lead to bionic hydrogels,which have suitable physicochemical and biological characteristics(e.g.,tribological and mechanical properties and the ability to support loadbearing capability),but need *** on their tribological and mechanical characteristics,the current review highlights the most recent advancements of bionic hydrogels used for articular cartilage,highlighting both the field's recent progress and its potential for future *** this reason,firstly,some important property improvement methods of bionic hydrogels are discussed and then,the recent findings of various research on the making of those bionic materials are provided and *** seems that by using some modifications such as product design,surface treatments,animal tests,controlling the isoelectric point of hydrogels,and computer simulation,the intended mechanical and tribological characteristics of natural articular cartilage may be attained by the bionic hydrogels.

关键词： Bionic hydrogel Articular cartilage Mechanical property Tribological property Lubrication

Ultrasensitive plasmonic sensor based on MDM waveguide containing Persian Orsi window cavities for refractive index and blood plasma sensing

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Optoelectronics Letters 2024年第7期20卷 406-411页

作者： mohammad Ghanavati mohammad Azim Karami School of Electrical Engineering Iran University of Science and TechnologyTehran 16846-13114Iran12

We developed a plasmonic refractive index(RI)with a metal-dielectric-metal(MDM)structure that utilizes two Persian Orsi windows-like separated cavities with a high figure of merit(FoM)and *** simulated and optimized Ag-air-Ag MDM sensor for surface plasmon resonance(SPR)offers high RI sensitivity(SRI)and the ability to detect blood plasma concentration(BPC).The results verified that structural parameters have an effect on SRI,full width at half maximum(FWHM),FoM,sensitivity of blood plasma(S_(p))for right and left peaks,whose values are 1345.45 nm·RIU^(−1),32 nm,42.04 RIU^(−1),0.26 and 0.19 nm·L·g^(-1),*** proposed design opens a new horizon in sensor development.

关键词： index utilize MDM

Enhanced adaptive nonlinear extended state observer for pure feedback systems with matched and mismatched disturbances

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Control Theory and Technology 2024年第2期22卷 254-268页

作者： Mahtab Delpasand mohammad Farrokhi School of Electrical Engineering Iran University of Science and TechnologyTehran16846-13114Iran Center of Excellence for Modelling and Control of Complex Systems Iran University of Science and TechnologyTehran16846-13114Iran

In this paper, an enhanced adaptive nonlinear extended state observer (EANESO) for single-input single-output pure feedback systems in the presence of external time-varying disturbances is proposed. In this paper, a nonlinear system with matched and mismatched disturbances is considered. The conventional extended state observer (ESO) can only be applied to systems that are in the form of integral chains. Moreover, this method has limitations in the face of mismatched disturbances. In the presence of time-varying disturbances, the traditional ESOs cannot estimate the disturbances accurately. To overcome this limitation, an EANESO is proposed in this paper. The main idea is to design the nonlinear ESO (NESO) to estimate the states of the system and multiple disturbances simultaneously. The observer gains are considered time-varying and adjusted with adaptation laws to improve the estimation accuracy and overcome the peaking phenomenon. Next, the proposed controller is designed based on output feedback to eliminate the effects of multiple disturbances and stabilize the closed-loop system. Subsequently, the stability analysis of the closed-loop system and convergence of the observer error are discussed. Finally, the proposed method is applied to the inverted pendulum system. The simulated results show good performance of the proposed method as compared with a recently published scheme in the related literature.

关键词： Nonlinear extended state observer Enhanced adaptive extended state observer Adaptation law Multiple-channel disturbances Inverted pendulum system Time-varying gain

The modeling non-sequential double ionization of helium atom under highintensity femtosecond laser pulses with shielding charge approximation

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Communications in Theoretical Physics 2024年第2期76卷 151-156页

作者： Marjan Zakavi mohammad Sabaeian Department of Physics Faculty of ScienceShahid Chamran University of AhvazIran Center for Research on Laser and Plasma Shahid Chamran University of AhvazIran

In this study,we successfully extracted the‘knee structure’for non-sequential double ionization(NSDI)in the helium *** achieve this,for the first time,we solved the time-dependent Schrödinger equation in three dimensions for the helium atom,utilizing the shielding charge *** findings corroborate prior observations by Wang et al[Wang and Eberly,***.105,083001(2010)],demonstrating that NSDI occurs within a narrower time window in circular polarization compared to linear *** a result,the yield of linear polarization was higher than that of circular polarization,aligning with the previously reported ***,in the case of circular polarization,the time window further narrows with increasing intensity,attributed to a decrease in the time-of-flight.

关键词： NSDI knee structure TDSE shielding charge helium 3D-TDSE