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Function of longitudinal vs circular muscle fibers in esophageal peristalsis, deduced with mathematical modeling

World Journal of Gastroenterology 2007年第9期13卷 1335-1346页

作者： James G Brasseur Mark A Nicosia anupam Pal Larry S Miller Department of Mechanical Engineering Pennsylvania State UniversityUniversity Park PA 16802United States Department of Mechanical Engineering Widener University ChesterPA 19013 United States Department of Biological Sciences & Bio-engineering Indian Institute of Technology Kanpur UP 208016 India Department of Gastroenterology Temple University Medical CenterPhiladelphiaPA 19140United States

We summarize from previous works the functions of circular vs. longitudinal muscle in esophageal peristaltic bolus transport using a mix of experimental data, the conservation laws of mechanics and mathematical modeling. Whereas circular muscle tone generates radial closure pressure to create a local peristaltic closure wave, longitudinal muscle tone has two functions, one physiological with mechanical implications, and one purely mechanical. Each of these functions independently reduces the tension of individual circular muscle fibers to maintain closure as a consequence of shortening of longitudinal muscle locally coordinated with increasing circular muscle tone. The physiological function is deduced by combining basic laws of mechanics with concurrent measurements of intraluminal pressure from manometry, and changes in cross sectional muscle area from endoluminal ultrasound from which local longitudinal shortening (LLS) can be accurately obtained. The purely mechanical function of LLS was discovered from mathematical modeling of peristaltic esophageal transport with the axial wall motion generated by LLS. Physiologically, LLS concentrates circular muscle fibers where closure pressure is highest. However, the mechanical function of LLS is to reduce the level of pressure required to maintain closure. The combined physiological and mechanical consequences of LLS are to reduce circular muscle fiber tension and power by as much as 1/10 what would be requiredfor peristalsis without the longitudinal muscle layer, a tremendous benefit that may explain the existence of longitudinal muscle fiber in the gut. We also review what is understood of the role of longitudinal muscle in esophageal emptying, reflux and pathology.

关键词：食管蠕动纵肌环肌肌纤维功能数学模型

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Appendiceal mucocoeles and pseudomyxoma peritonei

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World Journal of Gastroenterology 2007年第16期13卷 2381-2384页

作者： anupam Dixit John HP Robertson Satvinder S Mudan Charles Akle Department Third Floor the London Clinic London W1G 6BW United Kingdom

Mucocoele of the appendix occurs when obstruction of the appendiceal lumen results in mucus accumulation and consequent abnormal dilatation. The most impor- tant aetiology, from a surgical perspective, is either mucinous cystadenoma or cystadenocarcinoma. In the latter, a spontaneous or iatrogenic rupture of the mucocoele can lead to mucinous intraperitoneal ascites, a syndrome known as pseudomyxoma peritonei. Optimal management of mucoceles is achieved through accurate preoperative identification and subsequent careful resection. We report two cases and subsequently discuss the clinical presentation of mucocoeles, their association with pseudomyxoma peritonei and an optimal management of both conditions.

关键词：腹膜假性粘液瘤阑尾粘液囊肿外科手术治疗

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Piezoelectric Vibration Harvesters Based on Vibrations of Cantilevered Bimorphs: A Review

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Materials Sciences and Applications 2015年第9期6卷 818-827页

作者： Anam Khalid Amit Kumar Redhewal Manoj Kumar anupam Srivastav Mechanical Engineering Department IFTM University Moradabad India Middle East College Knowledge Oasis Muscat Sultanate of Oman

With the advancement in the technologies around the world over the past few years, the microelectromechanical systems (MEMS) have gained much attention in harvesting the energy for wireless, self-powered and MEMS devices. In the present era, many devices are available for energy harnessing such as electromagnetic, electrostatic and piezoelectric generator and these devices are designed based on its ability to capture the different form of environment energy such as solar energy, wind energy, thermal energy and convert it into the useful energy form. Out of these devices, the use of a piezoelectric generator for energy harvesting is very attractive for MEMS applications. There are various sources of harvestable energy including waste heat, solar energy, wind energy, energy in floating water and mechanical vibrations which are used by the researchers for energy harvesting purposes. This paper reviews the state-of-the-art in harvesting mechanical vibrations as an energy source by various generators (such as electromagnetic, electrostatic and piezoelectric generators). Also, the design and characteristics of piezoelectric generators, using vibrations of cantilevered bimorphs, for MEMS have also been reviewed here. Electromagnetic, electrostatic and piezoelectric generators presented in the literature are reviewed by taking into an account the power output, frequency, acceleration, dimension and application of each generator and the coupling factor of each transduction mechanism has also been discussed for all the devices.

关键词： Piezoelectric Generator Micro Electromechanical Systems (MEMS) Power Output Frequency Voltage

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Global, 30-m resolution continuous fields of tree cover: Landsat-based rescaling of MODIS vegetation continuous fields with lidar-based estimates of error

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International Journal of Digital Earth 2013年第5期6卷 427-448页

作者： Joseph O.Sexton Xiao-Peng Song Min Feng Praveen Noojipady anupam Anand Chengquan Huang Do-Hyung Kim Kathrine M.Collins Saurabh Channan Charlene DiMiceli John R.Townshend Global Land Cover Facility Department of Geographical SciencesUniversity of MarylandCollege ParkMDUSA Department of Geographical Sciences University of MarylandCollege ParkMDUSA

We developed a global,30-m resolution dataset of percent tree cover by rescaling the 250-m MOderate-resolution Imaging Spectroradiometer(MODIS)Vegetation Continuous Fields(VCF)Tree Cover layer using circa-2000 and 2005 Landsat images,incorporating the MODIS Cropland Layer to improve accuracy in agricultural *** Landsat-based estimates maintained consistency with the MODIS VCF in both epochs(RMSE=8.6%in 2000 and 11.9%in 2005),but showed improved accuracy in agricultural areas and increased discrimination of small forest *** lidar measurements,the Landsat-based estimates exhibited accuracy slightly less than that of the MODIS VCF(RMSE=16.8%for MODIS-based vs.17.4%for Landsat-based estimates),but RMSE of Landsat estimates was 3.3 percentage points lower than that of the MODIS data in an agricultural *** Landsat data retained the saturation artifact of the MODIS VCF at greater than or equal to 80%tree cover but showed greater potential for removal of errors through calibration to lidar,with post-calibration RMSE of 9.4%compared to 13.5%in MODIS *** for free download at the Global Land Cover Facility(GLCF)website(***),the 30-m resolution GLCF tree cover dataset is the highest-resolution multi=temporal depiction of Earth’s tree cover available to the Earth science community.

关键词： tree cover continuous fields Landsat MODIS lidar

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Thermal Effect on Vibration of Parallelogram Plate of Bi-Direction Linearly Varying Thickness

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Applied Mathematics 2011年第1期2卷 33-38页

作者： Arun K. Gupta Manoj Kumar Sanjay Kumar anupam Khanna 不详

In this paper, the effect of thermal gradient on the vibration of parallelogram plate with linearly varying thickness in both direction having clamped boundary conditions on all the four edges is analyzed. Thermal effect on vibration of such plate has been taken as one-dimensional distribution in linear form only. An approximate but quiet convenient frequency equation is derived using Rayleigh-Ritz technique with a two-term deflection function. The frequencies corresponding to the first two modes of vibration of a clamped parallelogram plate have been computed for different values of aspect ratio, thermal gradient, taper constants and skew angle. The results have been presented in tabular forms. The results obtained in this study are reduced to that of unheated parallelogram plates of uniform thickness and have generally been compared with the published one.

关键词： Parallelogram Plate Vibration Thermal Gradient Linearly Thickness Both Directions

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Structural and Morphological Study of a Series of Ball Milled Nanocrystalline Fe1-xAlx(0.3 ≤ x≤ 0.6) Alloys

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Journal of Modern Physics 2014年第8期5卷 643-648页

作者： Sandeep Rajan Rajni Shukla Anil Kumar anupam Vyas Ranjeet Brajpuriya Department of Physics Amity University Haryana Manesar India Department of Physics Deenbandhu Chhotu Ram University of Science & Technology Murthal India

In the present manuscript, the authors have systematically investigated the structural and morphological properties of a series of mechanically alloyed Fe1-xAlx (0.3 ≤ x ≤ 0.6) samples using X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). All the samples, after 5 hr of milling, show crystalline structure, irrespective of the constituent concentration and are textured mainly along (110) direction. In Fe-rich samples, the formation of an off-stoichiometric Fe3Al phase is favored and in case of Al-rich samples, both Al-rich phases and clustering of Al atoms are present. Analysis of line breadths was carried out to get an insight into the interrelated effects of average crystallite size, and lattice parameters. The grain size of constituents was decreased to the nanometer range (between 6 - 8 nm) and the constituents dissolved at the nanograin boundaries. Similar conclusions were also revealed from the SEM results which show that the initial shape of particles disappeared completely, and their structure became a mixture of small and large angularshaped crystallites with different sizes. The results of this research could be directly employed in the design of deformation schedules for the industrial processing of Fe-Al alloys.

关键词： Intermetallics FeAl Phase Formation XRD SEM Mechanical Alloying

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Terpenoids as potential chemopreventive and therapeutic agents in liver cancer

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World Journal of Hepatology 2011年第9期3卷 228-249页

作者： Roslin J Thoppil anupam Bishayee Cancer Therapeutics and Chemoprevention Group Department of Pharmaceutical Sciences Northeastern Ohio Universities Colleges of Medicine and Pharmacy Department of Internal Medicine Northeastern Ohio Universities Colleges of Medicine and Pharmacy

Despite significant advances in medicine, liver cancer, predominantly hepatocellular carcinoma remains a major cause of death in the United States as well as the rest of the world. As limited treatment options are currently available to patients with liver cancer, novel preventive control and effective therapeutic approaches are considered to be reasonable and decisive measures to combat this disease. Several naturally occurring dietary and non-dietary phytochemicals have shown enormous potential in the prevention and treatment of several cancers, especially those of the gastrointestinal tract. Terpenoids, the largest group of phytochemicals, traditionally used for medicinal purposes in India and China, are currently being explored as anticancer agents in clinical trials. Terpenoids (also called "isoprenoids") are secondary metabolites occurring in most organisms, particularly plants. More than 40 000 individual terpenoids are known to exist in nature with new compounds being discovered every year. A large number of terpenoids exhibit cytotoxicity against a variety of tumor cells and cancer preventive as well as anticancer efficacy in preclinical animal models. This review critically examines the potential role of naturally occurring terpenoids, from diverse origins, in the chemoprevention and treatment of liver tumors. Both in vitro and in vivo effects of these agents and related cellular and molecular mechanisms are highlighted. Potential challenges and future directions involved in the advancement of these promising natural compounds in the chemoprevention and therapy of human liver cancer are also discussed.

关键词： Terpenoids Liver cancer cells Hepatocellular carcinoma Hepatocarcinogenesis Chemoprevention Treatment Apoptosis Cell cycle

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Physio-Biochemical and Genetic Exploration for Submergence Tolerance in Rice (Oryza sativaL.) Landraces with Special References to Sub1 Loci

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American Journal of Plant Sciences 2015年第12期6卷 1893-1904页

作者： Sayani Goswami Reha Labar anupam Paul Malay Kumar Adak Narottam Dey Department of Biotechnology Visva-Bharati Santiniketan India Agricultural Training Centre Fulia India Department of Botany Plant Physiology and Plant Molecular Biology Research Unit University of Kalyani Kalyani India

In the present study a group of four indigenous and less popular rice genotypes (Meghi, Panibhasha, Jabra and Sholey) reported by growers as submergence tolerant lines from flood prone areas of south Bengal were explored through study of nodal anatomy, physio-biochemical screening under submergence and genotyping with submergence tolerance linked rice microsatellite loci (RM loci). To identify the different allelic forms of different Sub1 compnents (Sub1A, Sub1B and Sub1C) among the studied lines, the genomic DNA of individual genotypes was amplified with three ethylene response factor like genes from Sub1 loci, located on rice chromosome 9. From the different physio-biochemical experiments performed in this investigation, it has been shown that Meghi and Jabra are the two probable potent genotypes which share common properties of both submergence tolerant and deep water nature whereas rest two genotypes (Sholey and Panibhasha) behave like typical deep water rice. The submergence tolerance property of Meghi was also confirmed from submergence tolerance linked SSR based genotyping by sharing with FR13A for some common alleles as reflected in fingerprint derived dendrogram. The rest of the genotypes shared a number of alleles and were included in a separate cluster. The common behaviour of Meghi and FR13A under submergence was also confirmed from genetic study of Sub1 loci through sharing of some common alleles for three Sub1 components (Sub1A, Sub1B and Sub1C loci). One SSR loci (RM 285) was identified as a potent molecular marker for submergence tolerance breeding programme involving these two selected rice lines (Meghi and Jabra) as donor plant through marker assisted selection.

关键词： Rice Submergence Tolerance Rice Microsatellite Sub1 Loci Marker Assisted Breeding

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Primary repair of ear laceration with wedge resection

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Plastic and Aesthetic Research 2015年第1期2卷 38-39页

作者： Bhupinder Singla Inderjit Chawla Prasant Gautam anupam Goyal Jalaj Rathi Department of General Surgery Rajindra HospitalPatiala 147001PunjabIndia

Although major contributions have been made in the field of reconstructive surgery,reconstructive surgery of the auricle is a daunting prospect even for the most experienced ***,we present a case who presented to us in the emergency surgical ward with a history of an accidental laceration of right *** repair of the ear laceration after wedge resection of the avulsed part was *** cosmesis achieved by this technique is discussed.

关键词： Ear laceration primary repair wedge resection

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Role of Different Moisture Sources in Driving the Western Himalayan Past-glacier Advances

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Journal of Atmospheric Science Research 2023年第3期6卷 1-19页

作者： Prachita Arora Sheikh Nawaz Ali anupam Sharma Birbal Sahni Institute of Palaeosciences Lucknow226007India Academy of Scientific and Innovative Research Ghaziabad201002India

The fragmented pattern and the rapidly declining preservation of older glacial features/evidences limits the precision,with which glacial chronologies can be *** challenge is exacerbated by the scarcity of datable material and limitations of dating ***,the preserved glacial landforms have been fairly utilized to establish glacial chronologies from different sectors of the Indian *** existing Himalayan glacial chrono-stratigraphies have revealed that in a single valley,past glacial advances rarely surpass four ***,local and regional glacial chronologies must be synthesized to understand glacial dynamics and potential forcing *** research presents an overview of glacier responses to climate variations revealed by glacial chrono-stratigraphies in the western Indian Himalayan region over the Quaternary(late).The synthesis demonstrated that,although the glacial advances were sporadic,glaciers in western Himalayas generally advanced during the Marine isotope stage(MIS)-3/4,MIS-2,late glacial,Younger Dryas(YD)and Holocene *** Holocene has witnessed multiple glacial advances and the scatter is *** previous glacial research revealed that Himalayan glaciers were out of phase with the global last glacial maximum(gLGM),weak Indian Summer Monsoon(ISM)has been implicated(ISM was reduced by roughly 20%).Recent research,however,has shown that gLGM glaciation responded to the global cooling associated with the enhanced mid-latitude westerlies(MLW).Further,the magnitude of gLGM glacier advance varied along and across the Himalayas particularly the transitional valleys located between the ISM and MLW *** is also evident that both the ISM and MLW have governed the late Quaternary glacial advances in the western Himalayan ***,the responses of glaciers to ISM changes are more *** insights gained from this synthesis will help us understand the dynamics of glacier response to climate

关键词： Glacial chrono-stratigraphy Dating technique limits Climate drivers Western Himalaya India

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