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Artificial Intelligence in Gastrointestinal Endoscopy 2021年第4期2卷 179-184页

作者： gerald a cox ii Christian S Jackson Kenneth J Vega Department of Medicine Loma Linda University Medical CenterLoma LindaCA 92354United States Gastroenterology Section VA Loma Linda Healthcare SystemLoma LindaCA 92357United States Division of Gastroenterology and Hepatology Augusta University-Medical College of GeorgiaAugustaGA 30912United States

Gastrointestinal angiodysplasia(GIAD)is defined as the pathological process where blood vessels,typically venules and capillaries,become engorged,tortuous and thin walled–which then form arteriovenous connections within the mucosal and submucosal layers of the gastrointestinal *** are a significant cause of gastrointestinal bleeding and are the main cause for suspected small bowel *** make the diagnosis,gastroenterologists rely on the use of video capsule endoscopy(VCE)to“target”***,the use of VCE can be cumbersome secondary to reader fatigue,suboptimal preparation,and difficulty in distinguishing *** human eye is *** same capsule study read by two different readers are noted to have miss rates like other forms of *** intelligence(AI)has been a means to bridge the gap between human imperfection and recognition of *** use of AI in VCE have shown that detection has improved,however the other burdens and limitations still need to be *** use of AI for the diagnosis of GIAD shows promise and the changes needed to enhance the current practice of VCE are near.

关键词： Artificial intelligence Video capsule endoscopy Gastrointestinal angiodysplasia Detection Bleeding Small bowel

Heuristic Estimation of the Vacuum Energy Density of the Universe: Part ii-Analysis Based on Frequency Domain Electromagnetic Radiation

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Journal of Electromagnetic Analysis and Applications 2024年第1期16卷 1-9页

作者： Vernon Cooray gerald Cooray Marcos Rubinstein Farhad Rachidi Department of Electrical Engineering Uppsala University Uppsala Sweden Karolinska Institute Stockholm Sweden HEIG-VD University of Applied Sciences and Arts Western Switzerland Yverdon-les-Bains Switzerland Electromagnetic Compatibility Laboratory Swiss Federal Institute of Technology (EPFL) Lausanne Switzerland

In Part I of this paper, an inequality satisfied by the vacuum energy density of the universe was derived using an indirect and heuristic procedure. The derivation is based on a proposed thought experiment, according to which an electron is accelerated to a constant and relativistic speed at a distance L from a perfectly conducting plane. The charge of the electron was represented by a spherical charge distribution located within the Compton wavelength of the electron. Subsequently, the electron is incident on the perfect conductor giving rise to transition radiation. The energy associated with the transition radiation depends on the parameter L. It was shown that an inequality satisfied by the vacuum energy density will emerge when the length L is pushed to cosmological dimensions and the product of the radiated energy, and the time duration of emission is constrained by Heisenberg’s uncertainty principle. In this paper, a similar analysis is conducted with a chain of electrons oscillating sinusoidally and located above a conducting plane. In the thought experiment presented in this paper, the behavior of the energy radiated by the chain of oscillating electrons is studied in the frequency domain as a function of the length L of the chain. It is shown that when the length L is pushed to cosmological dimensions and the energy radiated within a single burst of duration of half a period of oscillation is constrained by the fact that electromagnetic energy consists of photons, an inequality satisfied by the vacuum energy density emerges as a result. The derived inequality is given by where is the vacuum energy density. This result is consistent with the measured value of the vacuum energy density, which is 5.38 × 10-10 J/m. The result obtained here is in better agreement with experimental data than the one obtained in Part I of this paper with time domain radiation.

关键词： Classical Electrodynamics Electromagnetic Radiation Action Radiated Energy Photon Heisenberg’s Uncertainty Principle Dark Energy Vacuum Energy Cosmological Constant Hubble Radius

Surgical Management of Perforated Colon Tumours in Yaoundé: A Multicentre Retrospective Review of 30-Day Postoperative Outcome

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Surgical Science 2024年第5期15卷 330-341页

作者： Eric Patrick Savom Richard ii Mbele Colman Tamboh Tankou Mahamat Yannick Ekani Boukar Cédric Paterson Atangana Fred Dikongue Dikongue Daniel Biwole Biwole Guy Aristide Bang Arthur Essomba Yaoundé General Hospital Yaound&#233 Cameroon Faculty of Medicine and Biomedical Sciences University of Yaound&#233 I Yaound&#233 Cameroon Faculty of Health Sciences University of Buea Buea Cameroon Faculty of Medicine and Biomedical Sciences University of Dschang Dschang Cameroon Yaoundé Central Hospital Yaound&#233 Cameroon Yaoundé University Teaching Hospital Yaound&#233 Cameroon

Introduction: Colon cancer is often diagnosed late in our context and there is a high prevalence of complicated forms, this including perforation. The optimal surgical treatment remains controversial. The aim of this study was to improve the short-term postoperative outcomes of patients operated upon for perforated colon cancer, by identifying factors associated with complications occurring within 30 days after surgery. Patients and methods: We carried out an analytical observational study, with a retrospective collection of data from the files of patients operated upon for an in situ tumoral colon perforation. This was done in four referral hospitals in the city of Yaoundé. The period was from the 1st of January, 2012 to the 31st of December, 2021. cox regression identified the factors associated with postoperative morbidity and mortality. Results: We collected files of 46 patients. The mean age was 54.7 ± 19.9 years with a sex ratio of 1.4. The clinical presentation on admission was dominated by the presence of signs of peritoneal irritation (91.3%) and bowel obstruction (28.3%). The diagnosis was made preoperatively in 16 cases (34.8%). The surgical procedures consisted of colectomy with anastomosis in 28 cases (60.9%) and without anastomosis in 14 cases (30.4%). Postoperative morbidity was 60.9% dominated by surgical site infection (37%). Postoperative mortality was 39.1%. The existence of generalized peritonitis was associated with the occurrence of postoperative complications (p = 0.019). The main factors associated with postoperative mortality were resection with primary anastomosis (p = 0.027), enterocutaneous fistula (p = 0.005). Conclusion: Colic resection with primary anastomosis or ideal colectomy is associated with an increased risk of mortality and should therefore not be performed in this setting.

关键词： Perforated Colon Cancer Postoperative Morbidity and Mortality Colectomy Acute Generalized Peritonitis

Mitofusin activation enhances mitochondrial motility and promotes neuroregeneration in CMT2A

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Neural Regeneration Research 2021年第11期16卷 2201-2203页

作者： gerald W.Dorn ii Department of Internal Medicine Washington University School of MedicineSt.LouisMOUSA

Human brains represent only 2%of body mass,but their high relative metabolic activity accounts for~20%of total body adenosine triphosphate(ATP)*** generated by neuronal mitochondria fuels nerve signaling and homeostatic *** the peripheral nervous system,which has greater capacity for regeneration after physical,toxic or genetic injury than the central nervous system,ATP also powers actin polymerization/depolymerization for growth cone formation and axon *** ATP generation is therefore a central component of neuronal functioning in the central and peripheral nervous systems.

关键词： motility activation regeneration

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The effect of the equatorially symmetric zonal winds of Saturn on its gravitational field

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Research in Astronomy and Astrophysics 2018年第4期18卷 15-22页

作者： Dali Kong Keke Zhang gerald Schubert John D.Anderson Key Laboratory of Planetary Sciences Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030 China College of Engineering Mathematics and Physical Sciences University of Exeter Exeter EX4 4QF UK Lunar and Planetary Science Laboratory Macao University of Science and Technology Macao China Department of Earth Planetary and Space Sciences University of California Los Angeles CA 90095-1567 USA Jet Propulsion Laboratory 4800 Oak Grove Drive Pasadena CA 91109 USA

The penetration depth of Saturn’s cloud-level winds into its interior is unknown.A possible way of estimating the depth is through measurement of the effect of the winds on the planet’s gravitational *** use a self-consistent perturbation approach to study how the equatorially symmetric zonal winds of Saturn contribute to its gravitational *** important advantage of this approach is that the variation of its gravitational field solely caused by the winds can be isolated and identified because the leading-order problem accounts exactly for rotational distortion,thereby determining the irregular shape and internal structure of the hydrostatic *** assume that（i）the zonal winds are maintained by thermal convection in the form of non-axisymmetric columnar rolls and（ii）the internal structure of the winds,because of the Taylor-Proundman theorem,can be uniquely determined by the observed cloud-level *** calculate both the variation △J_n,n=2,4,6...of the axisymmetric gravitational coefficients J_n caused by the zonal winds and the non-axisymmetric gravitational coefficients △J_（nm） produced by the columnar rolls,where m is the azimuthal wavenumber of the *** consider three different cases characterized by the penetration depth 0.36 R_S,0.2 R_S and 0.1 R_S,where R_S is the equatorial radius of Saturn at the 1-bar pressure *** find that the high-degree gravitational coefficient （ J_（12）＋△J_（12）） is dominated,in all the three cases,by the effect of the zonal flow with ｜△J_（12）/J_（12）｜〉100%and that the size of the non-axisymmetric coefficientsdirectly reflects the depth and scale of the flow taking place in the Saturnian interior.

关键词： gravitation — planets and satellites individual(Saturn) — planets and satellites interiors

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Uptake of Cystatin by Melanoma Cells in Culture

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CellBio 2013年第2期2卷 64-69页

作者： Lauren Deady James L. cox Department of Biochemistry AT Still University Kirksville USA Department of Biology Truman State University Kirksville USA

The cystatins are a super family of cysteine protease inhibitors which are ubiquitous in their biologic occurrence. Cystatin C, a type ii cystatin, is primarily a secreted protein found in most biological fluids. Besides acting as inhibitors of cathepsin, the cystatins have been found to have some non-inhibitor related functions and multiple physiological roles. Much interest has been generated for the cystatins as metastasis “suppressor-like” proteins, as they have been shown to inhibit metastasis for multiple cancer types. The sites and actions of the cystatins related to tumor suppressor actions are still unclear, however. In this work, we have examined the uptake of cystatin by metastatic melanoma cells in culture. Our results indicate cystatin uptake is mediated by a non-canonical endocytotic pathway in B16 murine melanoma cells.

关键词： Cystatin Melanoma Endocytosis Fluorescent

Down regulation of cyclooxygenase-2 is involved in delayed neuroprotec-tion by ischemic preconditioning in rats

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Acta Pharmacologica Sinica 2005年第4期26卷 441-446页

作者： Liang XIAO Fei-li ZHAO Xing-zu ZHU~1 Department of Pharmacology ii,Shanghai Institute of Materia Medica,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,Shanghai 201203,China Department of Pharmacology ii Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China

Aim:To examine whether the prostaglandins(PGs)pathway is involved in trigger-ing delayed neuroprotection by ischemic preconditioning(IPC)and evaluate theeffects of IPC on cyclooxygenase-2(cox-2)expression following focal cerebralischemia and reperfusion in ***:IPC was induced by 10 min of salineinfusion into the left internal carotid artery with the right common carotid arteryclamped at the same *** cerebral artery occlusion(MCAO)and reperfusionmodel was produced using intraluminal filament ***:IPC 48 h priorto MCAO significantly reduced infarct area as compared with MCAO *** inhibitor of cox indomethacin(3 mg/kg ip)applied 1 h prior to or 1 hafter IPC failed to affect its protective *** had no direct effect on thecortex cox-2 mRNA and protein expression 72 h later,but decreased the expres-sion of cox-2 mRNA and protein following ischemia and reperfusion ***:PGs pathways was not involved in triggering delayed neuroprotectionby IPC,and IPC induced down-regulation of cox-2 following focal cerebral is-chemia and reperfusion in rats in vivo.

关键词： ischemic preconditioning brain ischemia prostaglandins cyclooxygenase-2

Review Study of Detection of Diabetes Models through Delay Differential Equations

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Applied Mathematics 2016年第10期7卷 1087-1102页

作者： Dimplekumar Chalishajar David H. Geary Geoffrey cox Department of Applied Mathematics Virginia Military Institute Lexington VA USA

Mathematical models based on advanced differential equations are utilized to analyze the glucose-insulin regulatory system, and how it affects the detection of Type I and Type ii diabetes. In this paper, we have incorporated several models of prominent mathematicians in this field of work. Three of these models are single time delays, where either there is a time delay of how long it takes insulin produced by the pancreas to take effect, or a delay in the glucose production after the insulin has taken effect on the body. Three other models are two-time delay models, and based on the specific models, the time delay takes place in some sort of insulin production delay or glucose production delay. The intent of this paper is to use these multiple delays to analyze the glucose-insulin regulatory system, and how if it is not properly working at any point, the high risk of diabetes becomes a reality.

关键词： Delay Differential Equations MATLAB Diabetes Insulin-Glucose Model

The relevance of serum albumin among elderly patients with acute decompensated heart failure

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Journal of Geriatric Cardiology 2019年第7期16卷 522-528页

作者： Tuoyo O Mene-Afejuku Ela-Anamaria Moisa Adedoyin Akinlonu Carissa Dumancas Shushan Veranyan Jose A Perez Peggy Salazar Shobhana Chaudhari gerald Pekler Savi Mushiyev Ferdinand Visco Department of Medicine New York Medical College Metropolitan Hospital Center

Objective To assess the prognostic utility of serum albumin among elderly patients admitted for acute decompensated heart failure(ADHF)in terms of all-cause mortality and also to identify the predictors of *** Retrospective cohort study of 119 elderly patients admitted for *** patients were defined as patients over the age of 65 *** patients were followed up for approximately 11 *** with advanced renal failure,liver disease not due to HF,cancer and other causes of low life expectancy were *** was defined as serum albumin≤2.9 g/*** The study was made up of 65 females and 54 males with age ranging from 65 to 96 *** the 119 elderly patients with ADHF,there were 26 deaths.A significantly higher proportion of patients in the mortality group had an admission serum albumin level of≤2.9 g/dL than those surviving(P=0.011).After cox’s logistic regression,low albumin(P=0.016),elevated direct bilirubin(P=0.03),age greater than 85(P=0.008),lack of use of beta blockers(P=0.0001)and left ventricular ejection fraction less than 35%(P=0.005)increased the risk of *** serum creatinine(P=0.0357)was the only predictor of hypoalbuminemia following multiple linear *** Hypoalbuminemia may be an unrecognized marker of death in elderly patients with ADHF.

关键词： Albumin Heart Failure Mortality The elderly

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Studies on Extraction Behaviour of Cobalt(ii) with Nitrobenzoylprazolone-5

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Journal of Minerals and Materials Characterization and Engineering 2013年第3期1卷 90-94页

作者： Onyedika gerald Arinze Judith Ogwuegbu Martin Department of Industrial Chemistry Abia State University Uturu Nigeria Mineral Processing Unit Department of Chemistry Federal University of Technology Owerri Nigeria

The extraction of Cobalt(ii) from aqueous solution using 1-phenyl-3-methyl-4-(p-nitrobenzoyl)pyrazolone (HPMNP) in various organic solvents was studied as a function of pH and extractant concentration. Extraction into organic chloroform phase was more efficient than with any other solvent. The extraction equilibrium constant was found to be log Kex= -7.04. Optimum conditions for extraction of Co(ii) exist at pH of between 5.5 and 7.0, ionic strength of 0.3 Mand constant extractant concentration of 0.02 M. Shaking the organic Co(ii) chelate complex with 0.2 Macid strips the Co(ii) ions into the aqueous phase. It was established that Co(ii) complex extracted is of composition, Co(PMNP)2.

关键词： Extraction Solvent Complex Pyrazolones