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Artificial neural network based modeling of liquid membranes for separation of dysprosium

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Journal of Rare Earths 2023年第3期41卷 440-445,I0005页

作者： Jawad Iqbal arjun Tyagi Manish Jain Department of Applied Chemistry Delhi Technological UniversityDelhi110042India

In recent years,the liquid membrane process has been widely investigated to remove rare earth ***,transport modeling of this process requires the accurate values of several parameters,which are difficult to ***,the accurate simulation of this process is a challenging *** this study,the artificial neural network(ANN)based approach is used to model the liquid membrane process for removing *** results from a previous study were used to train the ***,the number of neurons in the hidden layer was *** minimum mean squared error between experimental results and model predictions is found with ten *** predictions were successfully validated with experimental results with correlation factor(R)of 0.9987,which confirms the authenticity of the trained *** ANN was then used to study the effects of different operating parameters on transport *** higher volume ratio of membrane solution to feed solution(3-4)with 50-60 min of operation,higher feed pH(5),HCl concentration in stripping solution of 2 mol/l,and moderate concentration of carrier species(0.5 mol/l)with 0.5×10^(-4) mol/l dysprosium initial concentration are found to be optimum values of operating conditions for maximizing the transport rate.

关键词： Rareearth metal separation Artificial neural network Dysprosium separation liquid membranes

Evaluation of phenolic composition, antioxidant, anti-inflammatory and anticancer activities of Polygonatum verticillatum(l.)

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Journal of Integrative Medicine 2018年第4期16卷 273-282页

作者： SANDeep Kumar Singh arjun Patra Institute of Pharmacy Guru Ghasidas University

Objective： Polygonaturn verticillatum （l） All. （Ruscaceae）, one of the Ashtawarga plants, is widely used for treatment of various ailments. The present study was undertaken to determine the phenolic composition, antioxidant, anti-inflammatory and anticancer activities of several extracts （petroleum ether, dichloro- methane, chloroform, ethanol, and aqueous） from the rhizomes of the plant. Methods： Coarsely powdered dry rhizome was successively extracted with different solvents of increas- ing polarity （petroleum ether, dichloromethane, chloroform, ethanol and water）. The phenolic composi- tions, in terms of total phenolic content （TPC）, total flavonoid content （TFC） and total condensed tannin content （JTC）, were evaluated with the Folin-Ciocalteu assay, aluminum chloride colorimetric assay and vanillin spectrophotometric assay, respectively. Total antioxidant capacity, 1,1-diphenyl-2- picrylhydrazyl and 2,2＇-azino-his（3-ethylbenzothiazoline-6-sulfonic acid） assays were used to assess the antioxidant potential of each extract. A protein denaturation model and 3-（4,5-dimethylthiazol-2- yl）-2,5-diphenyltetrazolium bromide assay were used to evaluate in vitro anti-inflammatory and anti- cancer activities, respectively. Gas chromatography-mass spectrometry （GC/MS） analysis was carried out to demonstrate various phytoconstituents in each extract. Correlation studies were also performed between phenolic composition （TPC, TFC and TFC） and different biological activities. Results： Ethanol extract showed maximum TPC （0.126 mg/g, gallic acid equivalent in dry sample）, TFC （0.094 mg/g, rutin equivalent in dry sample） and TTC （29.32 mg/g, catechin equivalent in dry sample）, as well as antioxidant and anti-inflammatory properties. Chloroform extract exhibited the strongest cyto- toxicity against the human breast cancer cell line, MCF-7. GC/MS analysis revealed the presence of 90 different phytoconstituents among the extracts. Antioxidant and anti-inflammatory activities had a pos

关键词： Polygonatum verticillatum Gas chromatography-mass spectrometry Phenolic profile MCF-7 cells

Innovative approaches to genome editing in avian species

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Journal of Animal Science and Biotechnology 2018年第2期9卷 278-284页

作者： Caitlin A.Cooper Timothy J.Doran arjun Challagulla Mark l.V.Tizard Kristie A.Jenkins CSIRO Health and Biosecurity Australian Animal Health Laboratory

The tools available for genome engineering have significantly improved over the last 5 years, allowing scientist to make precise edits to the genome. Along with the development of these new genome editing tools has come advancements in technologies used to deliver them. In mammals genome engineering tools are typically delivered into in vitro fertilized single cell embryos which are subsequently cultured and then implanted into a recipient *** avian species this is not possible, so other methods have been developed for genome engineering in birds. The most common involves in vitro culturing of primordial germ cells(PGCs), which are cells that migrate through the embryonic circulatory system to the developing gonad and colonize the gonad, eventually differentiating into the gonadocytes which produce either sperm or ova. While in culture the PGCs can be modified to carry novel transgenes or gene edits, the population can be screened and enriched, and then transferred into a recipient embryo. The largest drawback of PGC culture is that culture methods do not transfer well across avian species, thus there are reliable culture methods for only a few species including the chicken. Two newer technologies that appear to be more easily adapted in a wider range of avian species are direct injection and sperm transfection assisted gene editing(STAGE).The direct injection method involves injecting genome engineering tools into the circulatory system of the developing embryo just prior to the developmental time point when the PGCs are migrating to the gonads. The genome engineering tools are complexed with transfection reagents, allowing for in vivo transfection of the PGCs. STAGE utilizes sperm transfection to deliver genome engineering tools directly to the newly fertilized embryo. Preliminary evidence indicates that both methodologies have the potential to be adapted for use in birds species other than the chicken, however further work is needed in this area.

关键词： Avian CRISPR Genome engineering PGCs Sperm TAlEN

Thermal decomposition and kinetics of plastic bonded explosives based on mixture of HMX and TATB with polymer matrices

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Defence Technology（防务技术） 2017年第1期13卷 22-32页

作者： arjun Singh Tirupati C.Sharma Mahesh Kumar Jaspreet Kaur Narang Prateek Kishore Alok Srivastava Terminal Ballistics Research laboratory Defence Research&Development OrganisationMinistry of DefenceExplosive DivisionSector 30Chandigarh(UT)160030India Department of Chemistry&Centre for Advanced Studies in Chemistry Panjab UniversityChandigarh160 014India

This work describes thermal decomposition behaviour of plastic bonded explosives(PBXs) based on mixture of 1,3,5,7-tetranitro-1,3,5,7-tetrazocane(HMX) and 2,4,6-triamino-1,3,5-trinitrobenzene(TATB)with Viton A as polymer binder. Thermal decomposition of PBXs was undertaken by applying simultaneous thermal analysis(STA) and differential scanning calorimetry(DSC) to investigate influence of the HMX amount on thermal behavior and its kinetics. Thermogravimetric analysis(TGA) indicated that the thermal decomposition of PBXs based on mixture of HMX and TATB was occurred in a three-steps. The first step was mainly due to decomposition of HMX. The second step was ascribed due to decomposition of TATB, while the third step was occurred due to decomposition of the polymer matrices. The thermal decomposition % was increased with increasing HMX amount. The kinetics related to thermal decomposition were investigated under non-isothermal for a single heating rate measurement. The variation in the activation energy of PBXs based on mixture of HMX and TATB was observed with varying the HMX amount. The kinetics from the results of TGA data at various heating rates under non-isothermal conditions were also calculated by Flynn—Wall—Ozawa(FWO) and Kissinger-Akahira-Sunose(KAS)methods. The activation energies calculated by employing FWO method were very close to those obtained by KAS method. The mean activation energy calculated by FWO and KAS methods was also a good agreement with the activation energy obtained from single heating rate measurement in the first step decomposition.

关键词： Plastic bonded explosives Thermogravimetric analysis Differential scanning calorimeter Thermal decomposition Kinetics

A review of mechanisms of resistance to immune checkpoint inhibitors and potential strategies for therapy

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Cancer Drug Resistance 2020年第3期3卷 252-275页

作者： Yu Fujiwara arjun Mittra Abdul Rafeh Naqash Naoko Takebe Developmental Therapeutics Clinic Division of Cancer Treatment and DiagnosisNational Cancer InstituteBethesdaMD 20892USA. Department of Medical Oncology The Cancer Institute Hospital of Japanese Foundation for Cancer ResearchTokyo 1358550Japan Department of Medical Oncology Musashino Red Cross HospitalTokyo 1800023Japan

Immune checkpoint inhibitors(ICIs)have revolutionized the treatment of cancer over the last decade,bringing about a paradigm shift in systemic cancer therapy away from traditional cytotoxic and targeted *** some patients have dramatic treatment responses,it is sobering to note that most tumors are either resistant at the outset,or develop resistance after initial response.A major area of translational and clinical research is in identifying therapeutic strategies to overcome resistance to *** have performed an in-depth review of the different mechanisms of resistance and potential avenues to overcome resistance through rationally designed combination treatment with ICIs.

关键词： Immunotherapy resistance tumor microenvironment PD-1 PD-l1 CTlA-4

Exploring one material for dual applications:A red-emitting Mg_(2)GeO_(4):Eu^(3+)nanophosphor for future generation energy efficient WlEDs and dosimetric applications

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Journal of Rare Earths 2024年第10期42卷 1835-1845页

作者： Akshay arjun G.P.Darshan S.C.Sharma H.Nagabhushana D.V.Sunitha H.B.Premkumar Department of Physics Faculty of Mathematical and Physical SciencesM.S.Ramaiah University of Applied SciencesBengaluru560054India Honorary Professor of law and Forensic Materials Jain UniversityBengaluru560069India C.N.R.Rao Centre for Advanced Materials Tumkur UniversityTumkur572103India School of Applied Sciences(Physics) REVA UniversityBengaluru560064India

The envisaged design and developme nt of individual mate rials to excavate a broader spectrum of desired properties and offer multiple applications are highly *** this in mind,a series of forsterite-structured Mg_(2)GeO_(4):Eu^(3+)(1 mol%-9 mol%)nanophosphors was synthesized via a solution combustion method using oxalyl dihydrazide as a *** X-ray diffraction patterns confirm the orthorhombic crystal system with a Puma space *** results clearly show irregularly shaped cluster-like structures with aggregation of the *** diffuse reflectance spectra,the optical energy band gap of the Mg_(2)GeO_(4):Eu^(3+)(1 mol%-9 mol%)nanophosphors was estimated and obtained to be~4.12-4.32 *** photoluminescence emission spectra exhibit intense peaks at^(5)79,589,610,661,and 707 nm,which are due to characteristic^(5)D_(0)→^(7)F_(0),^(5)D_(0)→^(7)F_(1),^(5)Do→^(7)F_(2),^(5)D_(0)→^(7)F_(3)and^(5)D_(0)→^(7)F_(4)transitions of Eu^(3+)ions,*** Commission International de l'Eclairage color coordinates are gradually tuned from pale red(0.5980,0.4012)to a pure red(0.6385,0.3611)*** glow peaks showcase excellent super-linear response at low doses ofγ-irradiations,indicating that the prepared phosphor can be used in thermoluminescent personal dosimetry which is a biological tissue *** aforementioned results demonstrate that the prepared Mg_(2)GeO_(4):Eu^(3+)(1 mol%-9 mol%)nanophosphors are considered an excellent candidate for dual applications,i.e.,red component in future generation white-light-emitting diodes(WlEDs)and personal dosimetric applications.

关键词： Nanophosphors Photoluminescence Thermoluminescence Dosimetry Photometric properties Rare earths

Endovascular treatment of pulmonary embolism: Selective review of available techniques

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World Journal of Radiology 2017年第12期9卷 426-437页

作者： John l Nosher arjun Patel Sugeet Jagpal Christopher Gribbin Vyacheslav Gendel Division of Interventional Radiology Department of Radiology Rutgers Robert Wood Johnson Medical School Division of Pulmonary and Critical Care Me-dicine Department of Medicine Rutgers Robert Wood Johnson Medical School

Acute pulmonary embolism(PE) is the third most common cause of death in hospitalized patients. The development of sophisticated diagnostic and therapeutic modalities for PE, including endovascular therapy, affords a certain level of complexity to the treatment of patients with this important clinical entity. Furthermore, the lack of level I evidence for the safety and effectiveness of catheter directed therapy brings controversy to a promising treatment approach. In this review paper, we discuss the pathophysiology and clinical presentation of PE, review the medical and surgical treatment of the condition, and describe in detail the tools that are available for the endovascular therapy of PE, including mechanical thrombectomy, suction thrombectomy, and fibrinolytic therapy. We also review the literature available to date on these methods, and describe the function of the Pulmonary Embolism Response Team.

关键词： Pulmonary embolism Thrombolysis Endovascular Interventional radiology Thrombectomy Fibrinolysis

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基于稀疏表征的宽带信号DOA估计

基于稀疏表征的宽带信号DOA估计

作者： arjun SINGHA 哈尔滨工业大学

学位级别：硕士

阵列信号处理技术是属于高级信号处理技术的一大重要研究领域,主要对到达一组传感器节点处带噪信号进行检测和定位。近年来,阵列信号处理技术得到了快速发展。许多领域,比如无线通信、石油开采、雷达、声呐以及地震探查都需要到达角估计... 详细信息

阵列信号处理技术是属于高级信号处理技术的一大重要研究领域,主要对到达一组传感器节点处带噪信号进行检测和定位。近年来,阵列信号处理技术得到了快速发展。许多领域,比如无线通信、石油开采、雷达、声呐以及地震探查都需要到达角估计,而这正是阵列信号处理技术的主要研究内容。到达角估计包括传感器处理和分析它的空间谱。信号的空间谱表示了从所有方向到达接收机处信号的分布情况。因此,如果科研人员一旦能够获得了信号的空间谱,则所需信号的到达角就能够得知了。从这一方面来讲,我们也可以把空间谱估计成为到达角估计。本文主要研究基于信号稀疏表示的宽带信号到达角估计问题。信号的稀疏表示或者压缩感知技术是建立于这样的事实,即我们可以在合适的基底或者字典下将信号分解,仅仅使用一些非零的基底系数就可以,在一定误差范围内,表示原始信号。总所周知,根据奈奎斯特准则,当以感兴趣信号最高频率的2倍对该信号进行均匀采样,则可以在频域通过滤波器将原始信号无损恢复出来。不幸的是,在许多重要的和新兴的应用场合,达到符合奈奎斯特定理的超高采样速率会因为成本太高,或者在物理器件上不可行而难以实现。稀疏信号额可压缩信号都可以通过在合适基底下信号的最大基底系数值和该值所在位置,而高度精确地表示原始信号。利用变换编码的概念,压缩感知作为一个新的信号获取和传感器设计的框架而出现。通过压缩感知技术,可以将能够稀疏表示或者可压缩信号的采样开销和计算复杂度进行大规模地降低。另外,根据“奈奎斯特—香农”采样定理可知,为了完全获得任意一个带宽受限信号,必须要满足特定的最小采样频率。当信号在一个一组已知基底下具有稀疏性,我们可以大规模地减小需要存储的测量数据而不损失原始信号的特征。因此,相比于经典的信号表示技术及采样方法,利用信号稀疏表示技术或者压缩感知技术,我们或许可以得到更好的结果。以下就是压缩感知技术的基本理论观点:不同于先以高速率采样之后压缩样本数据,我们寻求直接以压缩的方式感知原始数据的方法,即完成低速率采样的任务。为解决处理这类高维度数据随之而来的逻辑和计算上的困难,我们常常依赖于压缩技术,即在满足可接受误差范围内,寻找感兴趣信号最简洁的表示方式。因此,我们需要稀疏表示技术或者压缩感知技术。基于到达角估计的压缩感知技术是基于以下观察到的情况,即一帮场景下,可能的信源数量圆圆小于可能的空间频率数量,也就是接收机接收到的信号本质上是可稀疏的。近年来,很多研究人员关注于稀疏基到达角估计技术,与早期的估计技术相比,该稀疏基到达角估计技术具有更高的估计效率。考虑到现有技术通过一个“连贯—平均”协方差矩阵或者通过最大似然的方法来恢复模型阶数,估计宽带新源个数是一项非常困难的任务。本文中将介绍l1-SVD技术作为主要的到达角估计技术。本文会提出一种基于传感器测量信号稀疏表示的信源定位方法,该稀疏表示是在一个过完备基底下完成的,该过完备基底是由阵列复制得到的采样值所组成。本文通过引入基于l1—范数的惩罚项来迫使信号具有稀疏性。一系列最近关于l1惩罚项的稀疏特征的理论结果证明了该方法的有效性。另外,本文使用数据矩阵的奇异值分解来概括多时间、对频率采样。许多研究领域,比如无线通信、石油开采、雷达、声呐以及地震探查都需要宽带信号的到达角估计。宽带信号具有在中心频率两侧非常宽的频带。并且,并不需要使用傅里叶变换或者通过信号插值来明确的波长和实验特点。对于宽带信源来说,常常在频域分析到达角问题。大部分现有的宽带到达角估计算法是将宽带信号分解为若干个窄带频率带,在估计到达角之前,将各个窄带频率带集中或者变换到一个参考频率间隔。本文中,使用了不同的频率带处理。首先,信号的整个频谱被划分为若干个小频段,每个小频段支持窄带近似,之后,在每一个小频段应用l1-SVD技术来获得相干谱。上述过程完成之后,我们仅仅将每一个小窄带频谱合成一个完全的宽带频谱。这个方法看起来很复杂,实际操作起来也确实很复杂,但本文选用这种方法是因为该方法是一种检测宽带信号的有效手段。除此之外,这项技术不需要任意的强假设条件,而其他现有的类似技术往往需要关于信号源较强的假设。本文提出的基于阵列输出多重采样奇异值分解的方法使用一个二阶锥形规划算法来优化得到的目标函数。该方法的关键在于使用一个合适的非二次正则化函数,该正则化函数会引出稀疏限制和超解。因此,源定位问题就变换成一个可以通过有效算法解决的凸优化问题。综上所述,本文将会给出一个基于宽带信源压缩感知的到达角估计综述。进展如下:(1)首先,为了方便初级读者本文给出了便于初学者理解到达角估计的基础知识,稀疏表示的必要理论基础,以及稀疏表示是如何与到达角估计建立联系的。(2)其次,我建立了带有阵列传感器的DOA估计情景的通用模型。之后,本文分别推导了窄带和宽带场景下的数学模型。l1-SVD技术首先针对窄带场景

关键词：窄带宽带稀疏表示反问题

Applying Novel Techniques from Physical and Biological Sciences to life Detection

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Space(Science & Technology) 2023年第1期3卷 325-338页

作者： Tony Z.Jia Chaitanya Giri Andrea Aldaba Ilknur Bahcivan Nipun Chandrasiri Ilankuzhali Elavarasan Kashish Gupta Sakshi P.khandare Christos liaconis Arpita Saha Orlando J.Solórzano Paola Ines Tiranti Aivaras Vilutis Graham E.lau Earth-life Science Institute Tokyo Institute of Technology2-12-1-IE-1 OokayamaMeguro-kuTokyo 152-8550Japan Blue Marble Space Institute of Science 6001st AveFloor 1SeattleWA 98104USA Research and Information System for Developing Countries(RIS) Core IV-BFourth FloorIndia Habitat CentreLodhi RoadNew Delhi 110003India Department of Physical and Natural Sciences School of Liberal EducationFLAME UniversityLavalePune 412115MaharashtraIndia School of Physical Sciences and Nanotechnology Yachay Tech University100119 UrcuquíEcuador

One of the primary goals of the space exploration community is to unambiguously detect past or present life outside of *** such,a number of so-called life detection technologies,instruments,and approaches have been applied as part of past,current,and future space *** astrobiology is a truly interdisciplinary field within the realm of space exploration with major contributions from physical and biological sciences(among others),recently there has been development of a number of relevant techniques from scientific fields that have yet to be fully applied to extraterrestrial life *** a culmination of the 2021 Blue Marble Space Institute of Science(BMSIS)Young Scientist Program(YSP),we present a number of techniques drawn from various fields(including,but not limited to,chemistry,materials science,biology,nanotechnology,medical science,astrophysics,and more)that either have been or have the potential to be applied to life detection *** techniques broadly fall under three categories:instrumentation for in situ measurements of biosignatures within the solar system,calculations or observational techniques for remote measurements of exoplanet biosignatures,and *** hope that this primer serves to inspire the field to consider applying more potential technologies from adjacent fields into any of these three categories of life detection.

关键词： signature applying outside