检索结果-南通市图书馆

Finite Deformation, Finite Strain Nonlinear Dynamics and Dynamic Bifurcation in TVE Solids with Rheology

Applied mathematics 2024年第1期15卷 108-168页

作者： karan S. Surana Sri Sai Charan mathi Department of mechanical Engineering University of Kansas Lawrence US

This paper presents a mathematical model consisting of conservation and balance laws (CBL) of classical continuum mechanics (CCm) and ordered rate constitutive theories in Lagrangian description derived using entropy inequality and the representation theorem for thermoviscoelastic solids (TVES) with rheology. The CBL and the constitutive theories take into account finite deformation and finite strain deformation physics and are based on contravariant deviatoric second Piola-Kirchhoff stress tensor and its work conjugate covariant Green’s strain tensor and their material derivatives of up to order m and n respectively. All published works on nonlinear dynamics of TVES with rheology are mostly based on phenomenological mathematical models. In rare instances, some aspects of CBL are used but are incorrectly altered to obtain mass, stiffness and damping matrices using space-time decoupled approaches. In the work presented in this paper, we show that this is not possible using CBL of CCm for TVES with rheology. Thus, the mathematical models used currently in the published works are not the correct description of the physics of nonlinear dynamics of TVES with rheology. The mathematical model used in the present work is strictly based on the CBL of CCm and is thermodynamically and mathematically consistent and the space-time coupled finite element methodology used in this work is unconditionally stable and provides solutions with desired accuracy and is ideally suited for nonlinear dynamics of TVES with memory. The work in this paper is the first presentation of a mathematical model strictly based on CBL of CCm and the solution of the mathematical model is obtained using unconditionally stable space-time coupled computational methodology that provides control over the errors in the evolution. Both space-time coupled and space-time decoupled finite element formulations are considered for obtaining solutions of the IVPs described by the mathematical model and are presented i

关键词： Thermoviscoelasticity Rheology memory Finite Strain Finite Deformation Nonlinear Dynamics Dynamic Bifurcation Ordered Rate Theories

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Lean body mass index is a marker of advanced tumor features in patients with hepatocellular carcinoma

引用

World Journal of Hepatology 2024年第3期16卷 393-404页

作者： Andrew Scott deLemos Jing Zhao milin Patel Banks Kooken karan m.thur Hieu minh Nguyen Areej mazhar maggie mcCarter Heather Burney Carla Kettler Naga Chalasani Samer Gawrieh Department of medicine Atrium HealthCharlotteNC 28204United States Center for Outcomes Research and Evaluation Atrium HealthCharlotteNC 28204United States Department of medicine Indiana University School of MedicineIndianapolisIN 46202United States Center for Health System Sciences(CHASSIS) Atrium HealthCharlotteNC 28204United States Department of medicine Northwestern University Feinberg School of MedicineChicagoIL 60611United States Department of Biostatistics and Health Data Science Indiana University School of MedicineIndianapolisIN 46202United States Department of Gastroenterology and Hepatology Indiana University School of MedicineIndianapolisIN 46202United States

BACKGROUND Obesity is an independent risk factor for the development of hepatocellular carcinoma(HCC)and may influence its ***,after diagnosis of HCC,like other malignancies,the obesity paradox may exist where higher body mass index(BmI)may in fact confer a survival *** is frequently observed in patients with advanced HCC and cirrhosis,who often present late with advanced tumor features and cancer related weight *** To explore the relationship between BmI and survival in patients with cirrhosis and *** This is a retrospective cohort study of over 2500 patients diagnosed with HCC between 2009-2019 at two United States academic medical *** and tumor characteristics were extracted manually from medical records of each institutions'cancer *** were stratified according to BmI classes:m^(2)(lean),25-29.9 kg/m^(2)(overweight),and>30 kg/m^(2)(obese).Patient and tumor characteristics were compared according to BmI *** performed an overall survival analysis using Kaplan meier by the three BmI classes and after adjusting for milan criteria.A multivariable Cox regression model was then used to assess known risk factors for survival in patients with cirrhosis and *** A total of 2548 patients with HCC were included in the analysis of which 11.2%(n=286)were classified as *** three main BmI categories:Lean(n=754),overweight(n=861),and obese(n=933)represented 29.6%,33.8%,and 36.6%of the total population *** each BmI class,the non-cirrhotic patients accounted for 15%(n=100),12%(n=94),and 11%(n=92),*** patients with a BmIm^(2)(n=52)were included in the lean *** the obese cohort,42%(n=396)had a BmI≥35 kg/m^(2).Out of 2262 patients with cirrhosis and HCC,654(29%)were lean,767(34%)were overweight,and 841(37%)were *** three BmI classes did not differ by age,mELD,or Child-Pugh *** hepatitis C was the dominant etiology in lea

关键词： Hepatocellular carcinoma Cirrhosis Obesity Body mass index class Sarcopenia Chronic hepatitis C

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

GPRC5B protects osteoarthritis by regulation of autophagy signaling

引用

药学学报:英文版 2023年第7期13卷 2976-2989页

作者： Liang He Ziwei Xu Xin Niu Rong Li Fanhua Wang Yu You Jingduo Gao Lei Zhao karan m.Shah Jian Fan mingyao Liu Jian Luo Yangzhi Rehabilitation Hospital(Shanghai Sunshine Rehabilitation Center) Tongji University School of MedicineShanghai 201613China Shanghai Key Laboratory of Regulatory Biology Institute of Biomedical Sciences and School of Life SciencesEast China Normal UniversityShanghai 200241China Department of Oncology and metabolism the Medical Schoolthe University of SheffieldSheffield S102TNUK Department of Orthopedics Tongji HospitalTongji University School of MedicineShanghai 200092China

Osteoarthritis(OA)is one of the most common chronic diseases in the ***,current treatment modalities mainly relieve pain and inhibit cartilage degradation,but do not promote cartilage *** this study,we show that G protein-coupled receptor class C group 5 member B(GPRC5B),an orphan G-protein-couple receptor,not only inhibits cartilage degradation,but also increases cartilage regeneration and thereby is protective against *** observed that Gprc5b deficient chondrocytes had an upregulation of cartilage catabolic gene expression,along with downregulation of anabolic genes in ***,mice deficient in Gprc5b displayed a more severe OA phenotype in the destabilization of the medial meniscus(Dmm)induced OA mouse model,with upregulation of cartilage catabolic factors and downregulation of anabolic factors,consistent with our in vitro *** of Gprc5b by lentiviral vectors alleviated the cartilage degeneration in Dmm-induced OA mouse model by inhibiting cartilage degradation and promoting *** also assessed the molecular mechanisms downstream of Gprc5b that may mediate these observed effects and identify the role of protein kinase B(AKT)-mammalian target of rapamycin(m TOR)-autophagy signaling ***,we demonstrate an integral role of GPRC5B in OA pathogenesis,and activation of GPRC5B has the potential in preventing the progression of OA.

关键词： Osteoarthritis GPRC5B Cartilage Chondrocyte Cartilage anabolism and catabolism Cartilage regeneration Autophagy Drug target

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Lineament analysis as a seismic precursor:The El mayor Cucapah earthquake of April 4,2010(mW7.2),Baja California,mexico

引用

Geodesy and Geodynamics 2023年第2期14卷 121-129页

作者： Rosendo Romero-Andrade manuel E.Trejo-Soto karan Nayak Daniel Hernández-Andrade Naccieli Bojorquez-Pacheco Faculty of Earth and Space Sciences Autonomous University of Sinaloa80013Culiacan RosalesSinaloaMexico

An earthquake called the mW7.2“El mayor Cucapah”earthquake on April 4,2010 has been analyzed for seismic *** changes in the lineament system concerning its pattern and time intervals were analyzed during the earthquake preparation period and occurrence using the automated lineament detection *** Landsat 5 Tm images were processed using LESSA and ADALGEO software obtaining similar *** statistical analysis revealed the stress accumulation due to plate interaction during earthquake *** study shows that the number of extracted lineaments changes rapidly about 23 months before the earthquake,and the systems return to the initial stage after 23 *** lineaments coincide with the extension of the San Andreas Fault as NW direction is the dominant ***,it can be concluded that the featural changes within the Rose diagram corresponding to the different strokes direction along with oriented elongation lines as disclosed in the present study using satellite images could be identified as a mid-term and/or short-term precursors of the ***,even though the dynamism of the El mayor Cucapah earthquake is found in the extracted lineaments,it is possible to isolate more significant earthquakes even if new ones appear near the ***,using two algorithms for lineament detection allows for the tectonics to corroborate the obtained lineaments and dynamism.

关键词： Lineament analysis Earthquake Landsat images Seismic precursor

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A Novel Hybrid Clustering Based Transmission Protocol for Wireless Body Area Networks

引用

Computers, materials & Continua 2021年第11期69卷 2459-2473页

作者： Neelam Sharma Harshita Chadha karan Singh B.m.Singh Nitish Pathak Research Scholar Computer Science and EngineeringUttarakhand Technical University(UTU)DehradunIndia Computer Science and Engineering Maharaja Agrasen Institute of TechnologyNew DelhiIndia School of Computer&Systems Sciences Jawaharlal Nehru University(JNU)DelhiIndia College of Engineering Roorkee UTUDehradunIndia Department of Information Technology KIET Group of InstitutionsGhaziabadIndia

Wireless sensor networks are a collection of intelligent sensor devices that are connected to one another and have the capability to exchange information packets amongst *** recent years,this field of research has become increasingly popular due to the host of useful applications it can potentially serve.A deep analysis of the concepts associated with this domain reveals that the two main problems that are to be tackled here are throughput enhancement and network security *** present article takes on one of these two issues namely the throughput *** the purpose of improving network productivity,a hybrid clustering based packet propagation protocol has been *** protocol makes use of not only clustering mechanisms of machine learning but also utilizes the traditional forwarding function approach to arrive at an optimum *** result of the simulation is a novel transmission protocol which significantly enhances network productivity and increases throughput value.

关键词： Forwarding function wireless sensor networks WSNs WBANs energy characteristics clustering hybrid mechanism dissipated energy network stability

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Using Pharmacokinetic modeling and Electronic Health Record Data to Predict Clinical and Safety Outcomes after methylprednisolone Exposure during Cardiopulmonary Bypass in Neonates

引用

Congenital Heart Disease 2023年第3期18卷 295-313页

作者： Henry P.Foote Huali Wu Stephen J.Balevic Elizabeth J.Thompson Kevin D.Hill Eric m.Graham Christoph P.Hornik karan R.Kumar Department of Pediatrics Duke UniversityDurhamUSA Duke Clinical Research Institute DurhamUSA Department of Pediatrics Medical University of South CarolinaCharlestonUSA

Background:Infants undergoing cardiac surgery with cardiopulmonary bypass(CPB)frequently receive intraoperative methylprednisolone(mP)to suppress CPB-related inflammation;however,the optimal dosing strategy and efficacy of mP remain ***:We retrospectively analyzed all infants under 90 days-old who received intra-operative mP for cardiac surgery with CPB from 2014–2017 at our *** combined real-world dosing data from the electronic health record(EHR)and two previously developed population pharmacokinetic/pharmacodynamic models to simulate peak concentration(Cmax)and area under the concentration-time curve for 24 h(AUC24)for mP and the inflammatory cytokines interleukin-6(IL-6)and interleukin-10(IL-10).We evaluated the relationships between post-operative,safety,and other clinical outcomes obtained from the EHR with each predicted exposure using non-parametric ***:A total of 142 infants with median post-natal age 8(interquartile range[IQR]:5,37)days received a total dose of 30(19,49)mg/kg of ***(8%)died,37(26%)met the composite post-operative outcome,114(80%)met the composite safety outcome,and 23(16%)had a major *** median Cmax and AUC24 IL-6 exposure was significantly higher for infants meeting the composite post-operative outcome and those with major *** median Cmax and AUC24 mP exposure was significantly higher for infants requiring *** exposure was associated with death or other safety ***:Pro-inflammatory IL-6,but not mP exposure,was associated with post-operative organ dysfunction,suggesting current mP dosing may not adequately suppress IL-6 or increase IL-10 to impact clinical *** study will be required to define the optimal exposure-efficacy and exposure-safety profiles in these infants.

关键词： Neonates cardiopulmonary bypass methylprednisolone exposure

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Enhanced Constitutive Theories for Classical Thermoviscoelastic Polymeric Fluids

引用

Applied mathematics 2022年第11期13卷 917-947页

作者： karan S. Surana Thomas J. Ezell Department of mechanical Engineering University of Kansas Lawrence KS USA

This paper presents ordered rate nonlinear constitutive theories for thermoviscoelastic fluids based on Classical Continuum mechanics (CCm). We refer to these fluids as classical thermoviscoelastic polymeric fluids. The conservation and balance laws of CCm constitute the core of the mathematical model. Constitutive theories for the Cauchy stress tensor are derived using the conjugate pair in the entropy inequality, additional desired physics, and the representation theorem. The constitutive theories for the Cauchy stress tensor consider convected time derivatives of Green’s strain tensor or the Almansi strain tensor up to order n and the convected time derivatives of the Cauchy stress tensor up to order m. The resulting constitutive theories of order (m, n) are based on integrity and are valid for dilute as well as dense polymeric, compressible, and incompressible fluids with variable material coefficients. It is shown that maxwell, Oldroyd-B, and Giesekus constitutive models can be described by a single constitutive theory. It is well established that the currently used maxwell and Oldroyd-B models predict zero normal stress perpendicular to the flow direction. It is shown that this deficiency is a consequence of not retaining certain generators and invariants from the integrity (complete basis) in the constitutive theory and can be corrected by including additional generators and invariants in the constitutive theory. Similar improvements are also suggested for the Giesekus constitutive model. model problem studies are presented for BVPs consisting of fully developed flow between parallel plates and lid-driven cavities utilizing the new constitutive theories for maxwell, Oldroyd-B, and Giesekus fluids. Results are compared with those obtained from using currently used constitutive theories for the three polymeric fluids.

关键词： Polymeric Fluids maxwell Oldroyd-B Giesekus mathematical models Nonlinear Rate Constitutive Theories Representation Theorem Integrity Generators Invariants

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

PGE2 activates EP4 in subchondral bone osteoclasts to regulate osteoarthritis

引用

Bone Research 2022年第2期10卷 378-393页

作者： Wenhao Jiang Yunyun Jin Shiwei Zhang Yi Ding Konglin Huo Junjie Yang Lei Zhao Baoning Nian Tao PZhong Weiqiang Lu Hankun Zhang Xu Cao karan mehul Shah Ning Wang mingyao Liu Jian Luo Yangzhi Rehabilitation Hospital(Sunshine Rehabilitation Centre) Tongji University School of MedicineShanghaiPR China Shanghai Key Laboratory of Regulatory Biology Institute of Biomedical Sciences and School of Life SciencesEast China Normal UniversityShanghaiPR China Departments of Orthopaedic Surgery and Biomedical Engineering and Institute of Cell Engineering The Johns Hopkins University School of MedicineBaltimoreMDUSA Department of Oncology and metabolism The University of SheffieldSheffieldUK

Prostaglandin E2(PGE2), a major cyclooxygenase-2(COX-2) product, is highly secreted by the osteoblast lineage in the subchondral bone tissue of osteoarthritis(OA) patients. However, NSAIDs, including COX-2 inhibitors, have severe side effects during OA treatment. Therefore, the identification of novel drug targets of PGE2 signaling in OA progression is urgently needed. Osteoclasts play a critical role in subchondral bone homeostasis and OA-related pain. However, the mechanisms by which PGE2 regulates osteoclast function and subsequently subchondral bone homeostasis are largely unknown. Here, we show that PGE2 acts via EP4 receptors on osteoclasts during the progression of OA and OA-related pain. Our data show that while PGE2 mediates migration and osteoclastogenesis via its EP2 and EP4 receptors, tissue-specific knockout of only the EP4 receptor in osteoclasts(EP4 Lys m) reduced disease progression and osteophyte formation in a murine model of OA. Furthermore, OA-related pain was alleviated in the EP4 Lys m mice, with reduced Netrin-1 secretion and CGRP-positive sensory innervation of the subchondral bone. The expression of plateletderived growth factor-BB(PDGF-BB) was also lower in the EP4 Lys mmice, which resulted in reduced type H blood vessel formation in subchondral bone. Importantly, we identified a novel potent EP4 antagonist, HL-43, which showed in vitro and in vivo effects consistent with those observed in the EP4 Lys mmice. Finally, we showed that the Gαs/PI3 K/AKT/mAPK signaling pathway is downstream of EP4 activation via PGE2 in osteoclasts. Together, our data demonstrate that PGE2/EP4 signaling in osteoclasts mediates angiogenesis and sensory neuron innervation in subchondral bone, promoting OA progression and pain, and that inhibition of EP4 with HL-43 has therapeutic potential in OA.

关键词： osteoclast homeostasis PGE2

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Compartmentalized metabolic Engineering for Artemisinin Biosynthesis and Effective malaria Treatment by Oral Delivery of Plant Cells

引用

molecular Plant 2016年第11期9卷 1464-1477页

作者： karan malhotra mayavan Subramaniyan Khushboo Rawat md. Kalamuddin m. Irfan Qureshi Pawan malhotra Asif mohmmed Katrina Cornish Henry Daniell Shashi Kumar1 metabolic Engineering Group malaria Research Group International Centre for Genetic Engineering and Biotechnology Aruna Asaf Ali Marg New Delhi 110067 India Department of Biotechnology Jamia Millia Islamia New Delhi 110025 India Department of Horticulture and Crop Science The Ohio State University Wooster OH 44691 USA Department of Biochemistry School of Dental Medicine University of Pennsylvania Philadelphia PA 19104 USA

Artemisinin is highly effective against drug-resistant malarial parasites, which affects nearly half of the global population and kills 〉500 000 people each year. The primary cost of artemisinin is the very expensive process used to extract and purify the drug from Artemisia annua. Elimination of this apparently unnecessary step will make this potent antimalarial drug affordable to the global population living in endemic regions. Here we reported the oral delivery of a non-protein drug artemisinin biosynthesized （~0.8 mg/g dry weight） at clinically meaningful levels in tobacco by engineering two metabolic pathways targeted to three different cellular compartments （chloroplast, nucleus, and mitochondria）. The doubly transgenic lines showed a three-fold enhancement of isopentenyl pyrophosphate, and targeting AACPR, DBR2, and CYP71AV1 to chloroplasts resulted in higher expression and an efficient photo-oxidation of di- hydroartemisinic acid to artemisinin. Partially purified extracts from the leaves of transgenic tobacco plants inhibited in vitro growth progression of Plasmodium falciparum-infected red blood cells. Oral feeding of whole intact plant cells bioencapsulating the artemisinin reduced the parasitemia levels in challenged mice in comparison with commercial drug. Such novel synergistic approaches should facilitate low-cost production and delivery of artemisinin and other drugs through metabolic engineering of edible plants.

关键词： bioencapsulation oral delivery of plant material dihydroartemisinic acid isopentenyl pyrophosphate,plant transformation drug biosynthesis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Fully integrated wearable impedance cytometry platform on flexible circuit board with online smartphone readout

引用

microsystems & Nanoengineering 2018年第1期4卷 234-243页

作者： Abbas Furniturewalla matthew Chan Jianye Sui karan Ahuja mehdi Javanmard Department of Electrical and Computer Engineering RutgersThe State University of New JerseyNew BrunswickUSA

We present a wearable microfluidic impedance cytometer implemented on a flexible circuit wristband with on-line smartphone readout for portable biomarker counting and *** platform contains a standard polydimethylsiloxane(PDmS)microfluidic channel integrated on a wristband,and the circuitry on the wristband is composed of a custom analog lock-in amplification system,a microcontroller with an 8-bit analog-to-digital converter(ADC),and a Bluetooth module wirelessly paired with a *** lock-in amplification(LIA)system is implemented with a novel architecture which consists of the lock-in amplifier followed by a high-pass filter stage with DC offset subtraction,and a post-subtraction high gain stage enabling detection of particles as small as 2.8μm using the 8-bit *** Android smartphone application was used to initiate the system and for offline data-plotting and peak counting,and supports online data readout,analysis,and file *** data is exportable to researchers and medical professionals for in-depth analysis and remote health *** system,including the microfluidic sensor,microcontroller,and Bluetooth module all fit on the wristband with a footprint of less than 80 *** demonstrate the ability of the system to obtain generalized blood cell counts;however the system can be applied to a wide variety of biomarkers by interchanging the standard microfluidic channel with microfluidic channels designed for biomarker isolation.

关键词： smart impedance wear

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：