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Two-Stent Strategy for Bifurcation Lesions in Percutaneous Transluminal Coronary Angioplasty: Real-World Evidence

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World Journal of Cardiovascular Diseases 2024年第3期14卷 140-156页

作者： Dilip Kumar Amit Malviya Animesh Mishra Rabin Chakraborty Sanjeev S. Mukherjee Soumya Patra Arindam Pande Rana Rathor roy Debopriyo Mondal Ashesh Halder Sumit Shanker Medica Superspecialty Hospital 127 Eastern Metropolitan Bypass Nitai Nagar Mukundapur Kolkata West Bengal India North Eastern Indira Gandhi Regional Institute of Health & Medical Sciences (NEIGRIHMS) Mawdiangdiang Shillong Meghalaya India

Background: Bifurcation lesions pose a high risk for adverse events after percutaneous coronary intervention (PCI). Evidence supporting the benefits of the two-stent strategy (2SS) for treating coronary bifurcation lesions in India is limited. This study aimed to evaluate the clinical outcomes of various 2SSs for percutaneous transluminal coronary angioplasty for bifurcation lesions in India. Materials and Methods: This retrospective, observational, multicentric, real-world study included 64 patients over 8 years. Data on demographics, medical history, PCI procedures, and outcomes were recorded. Descriptive statistics were computed using the SPSS software. Results: Patients (n = 64) had an average age of 65.3 ± 11.1 years, with 78.1% males. Acute coronary syndrome was reported in 18.8%, chronic stable angina in 40.6%, and unstable angina in 34.4% of participants. Two-vessel disease was observed in 98.4% of patients, and 99.4% had true bifurcation lesions. The commonly involved vessels were the left anterior descending artery (50%), left circumflex coronary artery (34.4%), and first diagonal artery (43.8%). Mean percent diameter stenosis was 87.2% ± 10.1%. The mean number of stents used was 2.00 ± 0.34. The 2SS techniques included the T and small protrusion (TAP) (39.1%), double kissing (DK) crush (18.8%), and the culotte techniques (14.1%). Procedural and angiographic success rate was 92.18%. Major adverse cardiovascular events at 1-year follow-up occurred in 7.8% of cases. Conclusion: The 2SS for bifurcation lesions showed favorable in-hospital and follow-up outcomes. Findings can serve as a resource for bifurcation angioplasty in India. Larger real-world studies with robust methodology are needed to validate these results.

关键词： Bifurcation Stenting Coronary Bifurcation Lesions Percutaneous

A Review on Thermophysical Properties and Nusselt Number Behavior of Al2O3 Nanofluids in Heat Exchangers

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Journal of Thermal Science 2021年第2期30卷 418-431页

作者： ISSA roy Jean College of Engineering West Texas A&M UniversityCanyonTexas 79016USA

During the last several years,the increase in cooling power requirements for heat exchangers have led to an escalation in heat transfer studies being performed on the use of nanofluids as heat transfer ***,limited effort has been attempted to relate and interpret these findings or the anomalies associated with *** paper compiles test data from several studies conducted on different types of heat *** this review,a concentrated effort is spent to clarify the ambiguities regarding the effect of nanoparticle size on the nanofluid thermal conductivity and Nusselt *** show that the nanofluid thermal conductivity is not influenced by the nanoparticle size,but by the clustering of the particles *** less compact the structure of the nanoparticle clustering is,the greater the enhancement in the nanofluid thermal conductivity *** were also compiled to interpret the relation between the nanofluid flow pattern,nanoparticles volume fraction in the base fluid,and the convective heat *** results from the majority of the heat exchanger studies show an increase in the heat transfer coefficient with the increase in nanoparticle volume ***,studies conducted on plate heat exchanges display some *** the majority of the heat exchanger studies with the exception of few,the decrease in the nanoparticle size is shown to result in an enhancement of the bulk fluid Nusselt *** test data also reveal that the effectiveness of the alumina nanoparticles is dependent on the flow *** increase in the nanoparticles concentration is shown to result in an increase in the nanofluid heat transfer enhancement as the fluid is transitioning from laminar to turbulent *** general,the smaller the nanoparticle size is,the greater the enhancement in the fluid Nusselt number is.

关键词： heat exchanger Nusselt number alumina nanofluid

A synchronous duty-cycled reservation based MAC protocol for underwater wireless sensor networks

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Digital Communications and Networks 2021年第3期7卷 385-398页

作者： Alak roy Nityananda Sarma Department of Information Technology Tripura UniversityWest TripuraIndia Department of Computer Science and Engineering Tezpur UniversityAssamIndia

To design an energy-efficient Medium Access Control(MAC)protocol for the Underwater Wireless Sensor Networks(UWSNs)is an urgent research issue since depleted batteries cannot be recharged or replaced in the underwater ***,the underwater acoustic channels are affected by hindrances such as long propagation delay and limited bandwidth,which appear in the design of the MAC protocol for the *** available MAC protocols for the terrestrial wireless sensor networks exhibit low performance in energy efficiency,throughput and reliability in the UWSNs,and cannot be used in the UWSNs directly because of their unique *** paper proposes a synchronous duty-cycled reservation-based MAC protocol named Ordered Contention MAC(OCMAC)*** basic mechanism of this protocol is to schedule data transmission by transmitters through the scheduling of Ready To Send(RTS)*** protocol eliminates the possible collision during data transmission and improves communication *** paper analyzes the performance in energy efficiency,throughput and reliability of the protocol by modeling the queuing behavior of OCMAC with a Markov Chain ***,the analytical model is validated through a simulation *** analysis results demonstrated that while providing good throughput and reliability,OCMAC can achieve energy saving.

关键词： Underwater wireless sensor networks MAC protocol Energy efficiency Throughput Reliability Acoustic communication OCMAC

Time evolution of the matter content of the expanding universe in the framework of Brans-Dicke gravity

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Research in Astronomy and Astrophysics 2019年第4期19卷 137-150页

作者： Sudipto roy Department of Physics St.Xavier's College30 Mother Teresa Sarani (Park Street)

A cosmological model has been constructed in the framework of Brans-Dicke(BD) gravity,based on an inter-conversion between matter and dark energy, for a spatially flat universe in the era of pressureless dust. To account for the non-conservation of the matter content, a function of time f(t) has been arbitrarily put into the expression for the density of matter(ρa^3= f(t)ρ_0 a_0~3). By definition, f(t) is proportional to the matter content of the universe. Using suitable ansatzes for the scale factor and scalar field, the functional form of f(t) has been determined from the BD field equations. The scale factor has been so chosen that it would cause a signature flip in the deceleration parameter with time. The function f(t) decreases monotonically with time, indicating a transformation of matter into dark energy. The time dependence of the proportions of matter and dark energy in the universe has been determined. The effect of non-conservation of the matter content upon various cosmological parameters has been explored in the present study. Two models of matter-energy interaction have been proposed and f(t) has been expressed as a function of their interaction term. The dark energy equation-of-state(EoS) parameter has been expressed and analyzed in terms of f(t).

关键词： cosmology:cosmological parameters dark energy Brans-Dicke theory

Hybrid optimization algorithm for modeling and management of micro grid connected system

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Frontiers in Energy 2014年第3期8卷 305-314页

作者： Kallol roy Kamal Krishna MANDAL Faculty of Electrical Engineering University Institute of Technology University of Burdwan Burdwan 713104 India

In this paper, a hybrid optimization algorithm is proposed for modeling and managing the micro grid （MG） system. The management of distributed energy sources with MG is a multi-objective problem which consists of wind turbine （WT）, photovoltaic （PV） array, fuel cell （FC）, micro turbine （MT） and diesel generator （DG）. Because, perfect economic model of energy source of the MG units are needed to describe the operating cost of the output power generated, the objective of the hybrid model is to minimize the fuel cost of the MG sources such as FC, MT and DG. The problem formulation takes into consideration the optimal configuration of the MG at a minimum fuel cost, operation and maintenance costs as well as emissions reduction. Here, the hybrid algorithm is obtained as artificial bee colony （ABC） algorithm, which is used in two stages. The first stage of the ABC gets the optimal MG configuration at a minimum fuel cost for the required load demand. From the minimized fuel cost functions, the operation and maintenance cost as well as the emission is reduced using the second stage of the ABC. The proposed method is implemented in the Maflab/ Simulink platform and its effectiveness is analyzed by comparing with existing techniques. The comparison demonstrates the superiority of the proposed approach and confirms its potential to solve the problem.

关键词： micro grid (MG) multi-objective function,artificial bee colony (ABC) fuel cost operation andmaintenance cost

Adaptive Execution of Jobs in Computational Grid Environment

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Journal of Computer Science & Technology 2009年第5期24卷 925-938页

作者： Sarbani roy Nandini Mukherjee Department of Computer Science and Engineering Jadavpur University

In a computational grid, jobs must adapt to the dynamically changing heterogeneous environment with an objective of maintaining the quality of service. In order to enable adaptive execution of multiple jobs running concurrently in a computational grid, we propose an integrated performance-based resource management framework that is supported by a multi-agent system （MAS）. The multi-agent system initially allocates the jobs onto different resource providers based on a resource selection algorithm. Later, during runtime, if performance of any job degrades or quality of service cannot be maintained for some reason （resource failure or overloading）, the multi-agent system assists the job to adapt to the system. This paper focuses on a part of our framework in which adaptive execution facility is supported. Adaptive execution facility is availed by reallocation and local tuning of jobs. Mobile, as well as static agents are employed for this purpose. The paper provides a summary of the design and implementation and demonstrates the efficiency of the framework by conducting experiments on a local grid test bed.

关键词： grid environment multi-agent system adaptive execution Jini mobile agent

Heat Transfer Optimization for Air-Mist Cooling between a Stack of Parallel Plates

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Journal of Thermal Science 2010年第3期19卷 253-260页

作者： roy J.Issa Mechanical Engineering Division Department of Engineering and Computer Science West Texas A&M University CanyonTexas 79016USA

A theoretical model is developed to predict the upper limit heat transfer between a stack of parallel plates subject to multiphase cooling by air-mist *** model predicts the optimal separation distance between the plates based on the development of the boundary layers for small and large separation distances,and for dilute mist *** results show the optimal separation distance to be strongly dependent on the liquid-to-air mass flow rate loading ratio,and reach a limit for a critical *** these dilute spray conditions,complete evaporation of the droplets takes *** results also show the optimal separation distance decreases with the increase in the mist flow *** proposed theoretical model shall lead to a better understanding of the design of fins spacing in heat exchangers where multiphase spray cooling is used.

关键词： Air-mist Multiphase Heat transfer Liquid-to-air loading

Seismic demand of plan-asymmetric structures:a revisit

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Earthquake Engineering and Engineering Vibration 2013年第1期12卷 99-117页

作者： Rana roy Suvonkar Chakroborty Department of Aerospace Engineering & Applied Mechanics Bengal Engineering and Science UniversityShibpurIndia SMS India Pvt.Ltd. SMS GroupIndia

In view of the recognition of the importance of the interdependent behavior of strength and stiffness of walltype structural elements,the seismic demand of plan-asymmetric systems is *** strength distribution strategies,i.e.,＇Center of Strength-Center of Mass（CV-CM） coinciding＇ and ＇Balanced Center of Strength-Center of Resistance（CVCR）＇ are *** charts for the seismic demand of classical uni-directionally and bi-directionally asymmetric systems are developed in a simple unified format.A conceptual framework is also outlined to conveniently apply the design *** are included to explain the use of the current recommendations in practical *** study also highlights the relative performance of ＇CV-CM coinciding＇ and ＇Balanced CV-CR＇ criteria.

关键词： asymmetry seismic strength dependent stiffness design chart

Targeting BPOZ-2 in Lewy body disease

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Neural Regeneration Research 2016年第6期11卷 910-911页

作者： Avik roy Department of Neurological Sciences Rush University Medical Center

Formation of Lewy body inclusions（LBs）in the substantia nigra（SN）is a very well-characterized pathological hallmark of Parkinson’s disease（PD）.LBs are aggregates of many biologically inactive proteins including structural elements,alpha-synuclein（asyn）-binding proteins,synphilin-1-binding proteins,and components of the ubiquitin-proteasome system.

关键词： Targeting substantia proteasome nigra ubiquitin biologically inactive mitochondria dopamine parkin