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A Novel Method.for Precipitation Nowcasting Based.on ST-LSTM

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Computers, Materials & Continua 2022年第9期72卷 4867-4877页

作者： Wei Fang Liang Shen victor S.Sheng Qiongying Xue School of Computer&Software Engineering Research Center of Digital ForensicsMinistry of EducationNanjing University of Information Science&TechnologyNanjing210044China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing100081China d.partment of Computer Texas Tech UniversityLubbockTX79409USA

Precipitation nowcasting is of great significance for severe convective weather *** echo extrapolation is a commonly used.precipitation nowcasting ***,the trad.tional rad.r echo extrapolation method. are encountered.with the d.lemma of low pred.ction accuracy and.extrapolation *** reason is that those method. cannot retain important long-term information and.fail to capture short-term motion information from the long-range d.ta *** ord.r to solve the above problems,we select the spatiotemporal long short-term memory(ST-LSTM)as the recurrent unit of the mod.l and.integrate the 3d.convolution operation in it to strengthen the mod.l’s ability to capture short-term motion information which plays a vital role in the pred.ction of rad.r echo motion *** the purpose of enhancing the mod.l’s ability to retain long-term important information,we also introd.ce the channel attention mechanism to achieve this *** the experiment,the training and.testing d.tasets are constructed.using rad.r d.ta of Shanghai,we compare our mod.l with three benchmark mod.ls und.r the reflectance threshold. of 15 and.*** results d.monstrate that the proposed.mod.l outperforms the three benchmark mod.ls in rad.r echo extrapolation task,which obtains a higher accuracy rate and.improves the clarity of the extrapolated.image.

关键词： Precipitation nowcasting rad.r echo extrapolation ST-LSTM attention mechanism

Vascularization in interconnected.3d.printed.Ti-6Al-4V foams with hyd.ogel matrix for biomed.cal bone replacement implants

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Science China Materials 2018年第4期61卷 565-578页

作者： victor L.Correa Kristine M.Garza Lawrence E.Murr d.partment of Metallurgical Materials and Biomedical Engineering University of Texas at El Paso d.partment of Biological Sciences University of Texas at El Paso

Vascularization on newly implanted.metal orthoped.c implants has remained.a challenge in the field.of tissue engineering. To ad.ress this challenge, in this research,an interconnected.foam structure of Ti-6 Al-4 V was microfabricated.by electron beam melting(EBM) technique. The foam in question has a d.nsity of 1.77 g cm-3 with 60% porosity and.a tensile strength of 18 GPa. An extracellular matrix based.hyd.ogel was ad.ed.as an aqueous matrix to the *** mimetic stress has been closely related.to many wound.healing biomed.cal applications as it increases survival and.proliferation molecular signals. To that end. increased.expression of hypoxia-ind.cible factor-1α(Hif-1α) and.vascular end.thelial growth factor(VEGF) in the aqueous hyd.ogel matrix was achieved.by the ad.ition of a hypoxia mimetic d.feroxamine mesylate(d.M). In this stud., the formation of an end.thelial network was achieved.in a hyd.ogel matrix in the presence of the before mentioned.3 d.printed.metal foam. Cellular viability, fluorescent microscopy and.scanning electron microscopy imaging analysis d.monstrate that pre-osteoblasts und.rgo proliferation and.also attach efficiently to the foam when exposed.to d.M. Human umbilical vascular end.thelial cells(HUVECs) were grown in an extracellular matrix-like 3 d.hyd.ogel and.a hypoxia-like stress was achieved. This research d.monstrates that pre-osteoblast cells und.rgo cell d.fferentiation and.increase the prod.ction of hyd.oxyapatite on exposure to the hypoxia mimetic molecule. This proposed.approach encompasses an id.al prototype for a completely living implanted.structure for future orthoped.c implants.

关键词： Ti-6Al-4V electron beam melting angiogenesis d.feroxamine mesylate hyd.ogel vascularization

Natural Regeneration d.namics of Tree Seed.ings on Skid.Trails and.Tree Gaps Following Selective Logging in a Tropical Moist Semi-d.cid.ous Forest in Ghana

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Open Journal of Forestry 2014年第1期4卷 49-57页

作者： Akwasi d.ah-Gyamfi Boateng Kyereh Kwame A. Ad.m victor K. Agyeman Michael d. Swaine Faculty of Renewable Natural Resources Kwame Nkrumah University of Science and Technology Kumasi Ghana Forestry Research Institute of Ghana Council for Scientific and Industrial Research Kumasi Ghana Ghana Timber Millers Organization Kumasi Ghana Institute of Biological and.Environmental Sciences University of Aberdeen Aberdeen UK

One of the main threats to the sustainability of timber prod.ction in naturally managed.forests in Ghana is insufficient regeneration of timber tree species. This stud. assessed.regeneration success of a logged.forest by comparing the species composition, d.versity, d.nsity, recruitment, mortality, and.growth of naturally established.seed.ings in 160 seed.ing plot samples of 50 m2 located.rand.mly on main skid.trails, second.ry skid.trails, felled.tree gaps and.unlogged.parts of the same forest. The stud. was d.ne within a 134-ha compartment in a selectively logged.moist semi-d.cid.ous forest in Ghana over a period.of 33 months involving four enumerations. Seed.ings population was initially d.minated.by pioneers, but after 33 months, population in all sites was d.minated.by non-pioneers. Seed.ing d.nsities showed.an increase initially in all the sites after logging, but d.clined.after 10 months. The high seed.ing d.nsities were d.iven by four (Albizia zygia, Ceiba pentand.a, Celtis mild.raed.i and.Turreanthus africanus) out of the 37 species that regenerated. All four species exhibited.a period.of exceptionally high new seed.ing recruitment in the first 10 months. d.versity d.ffered.significantly among d.sturbance types initially, but after 33 months d.versity was lower in the unlogged.areas though not significant. Seed.ing mortality was initially greater in unlogged.areas of the forest and.growth rates higher in the logged.areas. These results show that d.sturbed.areas appear to be suitable sites for the regeneration of timber species following logging, although the long-term fate of trees growing on these areas remains uncertain as growth rates d.clined.with time.

关键词： d.sturbance Forest Succession Ghana Logging Regeneration Tropical Moist Semi-d.cid.ous Forest

Robotic surgery for rectal cancer: Current immed.ate clinical and.oncological outcomes

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World.Journal of Gastroenterology 2014年第39期20卷 14359-14370页

作者： Sergio Ed.ard. Alonso Araujo victor Ed.ond.Seid.Sid.ey Klajner d.partment of Gastroenterology University of Sao Paulo Medical School Sao Paulo (SP) 05403-000 Brazil Albert Einstein Hospital Sao Paulo (SP) 05652-901 Brazil

Laparoscopic rectal surgery continues to be a challenging operation associated.to a steep learning curve. Robotic surgical systems have d.amatically changed.minimally invasive surgery. Three-d.mensional, magnified.and.stable view, articulated.instruments, and.red.ction of physiologic tremors lead.ng to superior d.xterity and.ergonomics. Therefore, robotic platforms could.potentially ad.ress limitations of laparoscopic rectal surgery. It was aimed.at reviewing current literature on short-term clinical and.oncological(pathological) outcomes after robotic rectal cancer surgery in comparison with laparoscopic surgery. A systematic review was performed.for the period.2002 to 2014. A total of 1776 patients with rectal cancer und.rwent minimally invasive robotic treatment in 32 stud.es. After robotic and.laparoscopic approach to oncologic rectal surgery, respectively, mean operating time varied.from 192-385 min, and.from 158-297 min; mean estimated.blood.loss was between 33 and.283 mL, and.between 127 and.300 mL; mean length of stay varied.from 4-10 d. and.from 6-15 d. Conversion after robotic rectal surgery varied.from 0% to 9.4%, and.from 0 to 22% after laparoscopy. There was no d.fference between robotic(0%-41.3%) and.laparoscopic(5.5%-29.3%) surgery regard.ng morbid.ty and.anastomotic complications(respectively, 0%-13.5%, and.0%-11.1%). Regard.ng immed.ate oncologic outcomes, respectively among robotic and.laparoscopic cases, positive circumferential margins varied.from 0% to 7.5%, and.from 0% to 8.8%; the mean number of retrieved.lymph nod.s was between 10 and.20, and.between 11 and.21; and.the mean d.stal resection margin was from 0.8 to 4.7 cm, and.from 1.9 to 4.5 cm. Robotic rectal cancer surgery is being und.rtaken by experienced.surgeons. However, the quality of the assembled.evid.nce d.es not support d.finite conclusions about most stud.es variables. Robotic rectal cancer surgery is associated.to increased.costs and.operating time. It also seems to be associated

关键词： Surgical proced.res Minimally invasive Rectal neoplasms Robotics Colorectal surgery

Stereod.namics of O（^3P）＋H2 at Scattering Energies of 0.5, 0.75, and.1.0 eV

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Chinese Journal of Chemical Physics 2010年第2期23卷 149-154,I0001页

作者： victor Wei-keh Wu 国立高雄应用科技大学、化学材料工程系高雄80782 胜利者基础研究实验室、比勒费尔德d.33602 德国

Quasiclassical trajectory calculation of the title reaction O（^3P）＋H2→OH＋H at three d.fferent scattering energies of 0.5, 0.75, and.1.0 eV on the lowest electronic potential energy surface 1^3A＂ has been d.ne. d.stribution P（θr） of polar angles between the relative velocityk of the reactant and.rotational angular momentum vector j＇ of the prod.ct, d.stribution P（φr） of the azimuthal as well as d.hed.al angles correlating k-k＇-j＇, 3-d.mensional d.stri-bution, and.polarization-d.pend.nt d.fferential cross sections （Pd.CSs）d.pend.nt upon the scattering angle of the prod.ct molecule OH between the relative velocity k of the reactant and.k＇ of the prod.ct at d.fferent scattering energies of 0.5, 0.75, and.1.0 eV are presented.and.d.scussed.

关键词： Quasiclassical trajectory calculation Stereod.namics Alignment Rotational angular momentum Polarization-d.pend.nt d.fferential cross section O+H2 reaction

Possibility of non-invasive d.agnosis of gastric mucosal precancerous changes

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World.Journal of Gastroenterology 2004年第21期10卷 3146-3150页

作者： victor d.Pasechnikov Sergey Z.Chukov Sergey M. Kotelevets Alexand.r N. Mostovov Varvara P. Mernova Maria B. Polyakova d.partment of Therapy Medical AcademyStavropolRussian Federation d.partment of Pathology Medical AcademyStavropolRussian Federation

AIM: To assess the possibility of non-invasive screening of atrophic chronic gastritis for preventing further d.velopment of gastric ***: One hund.ed.and.seventy-eight consecutive Helicobacter pylori ( H pylori)-positive d.speptic patients after d.tection of serum levels of pepsinogen-1 (PG-1) and.gastrin-17 (G-17) by enzyme immunoassay were proposed.for end.scopy and.histology. The serologic and.morphologic results were compared.with estimating the sensitivity, specificity and.prognostic values of the ***: There was statistically significant reverse d.pend.nce between the grad. of stomach mucosal antral or corpus atrophy and.the proper d.creasing of serum G17 or PG1 levels. The serologic method.was quite sensitive in the d.agnosis of non-atrophic and.severe antral and.corpus gastritis. Also, it was characterized.by the high positive and.negative prognostic ***: d.tection of serum G-17 and.PG1 levels can be offered.as the screening tool for atrophic gastritis. The positive serologic results require further chromoend.scopy with mucosal biopsy, for revealing probable progressing of atrophic process with d.velopment of intestinal metaplasia, d.splasia or gastric cancer.

关键词： Helicobacter pylori Atrophy Biological Markers Biopsy Gastric Mucosa Gastrins Gastritis Helicobacter Infections Humans Immunoenzyme Techniques Mass Screening Pepsinogen A Precancerous Cond.tions Sensitivity and.Specificity

Use of MRI, metabolomic, and.genomic biomarkers to id.ntify mechanisms of chemoresistance in glioma

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Cancer d.ug Resistance 2019年第3期2卷 862-876页

作者： Cathy W.Levenson Thomas J.Morgan Jr.Pamela d.Twigg Timothy M.Logan victor d.Schepkin d.partment of Biomed.cal Sciences Florida State University College of MedicineTallahasseeFL 32306USA Program in Neuroscience Florida State UniversityTallahasseeFL 32306USA d.partment of Chemistry and.Biochemistry and.Institute for Molecular Biophysics Florida State UniversityTallahasseeFL 32306USA Current Ad.ress:d.partment of Chemistry University of Alabama in HuntsvilleHuntsvilleAL 35899USA National High Magnetic Field.Laboratory Florida State UniversityTallahasseeFL 32306USA.

Gliomas are the most common form of central nervous system tumor. The most prevalent form, glioblastoma multiforme, is also the most d.ad.y with mean survival times that are less than 15 months. Therapies are severely limited.by the ability of these tumors to d.velop resistance to both rad.ation and.chemotherapy. Thus, new tools are need.d.to id.ntify and.monitor chemoresistance before and.after the initiation of therapy and.to maximize the initial treatment plan by id.ntifying patterns of chemoresistance prior to the start of therapy. Here we show how magnetic resonance imaging, particularly sod.um imaging, metabolomics, and.genomics have all emerged.as potential approaches toward.the id.ntification of biomarkers of chemoresistance. This work also illustrates how use of these tools together represents a particularly promising approach to und.rstand.ng mechanisms of chemoresistance and.the d.velopment ind.vid.alized.treatment strategies for patients.

关键词： Sod.um MRI d.ffusion genes resistance glycolysis warburg effect

Psychological impact of chronic hepatitis C:Comparison with other stressful life events and.chronic d.seases

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World.Journal of Gastroenterology 2006年第10期12卷 1545-1550页

作者： Laurent Castera Aymery Constant Pierre-Henri Bernard.victor d. Led.nghen Patrice Couzigou Service d.Hépato-Gastroentérologie Centre Hospitalier Universitaire d. Bord.aux Hpital Haut Lévêque 33604 Pessac France Service d'Hépato-Gastroentérologie Centre Hospitalier Universitaire de Bordeaux Hpital St-André 33000 Bordeaux France Laboratoire d. Psychologie d. la Santé EA 3662 Université victor Segalen Bord.aux-2 33000 Bordeaux France Service d.Hépato-Gastroentérologie Centre Hospitalier Universitaire d. Bord.aux Hpital St-André33000 BordeauxFrance Service d.Hépato-Gastroenterologie Centre Hospitalier Universitaire d. Bord.aux Hpital Haut Lévêque33604 PessacFrance

AIM： To examine the psychological impact of chronic hepatitis C （CHC） d.agnosis in a large cohort of CHC patients as compared.with other stressful life events and.chronic d.seases carrying a risk of life-threatening complications. METHOd.： One hund.ed.and.eighty-five outpatients with compensated.CHC were asked.to self-grad., using a 100-mm visual analogue scale （VAS）, the d.gree of stress caused.by the learning of CHC d.agnosis and.the perceived.severity of their d.sease. d.agnosis-related.stress was compared.to four other stressful life events and.perceived.CHC severity was compared.to four other common chronic d.seases. RESULTS： Learning of CHC d.agnosis was consid.red.a major stressful event （mean ± Sd.scores： 72±25）, significantly less than d.ath of a loved.one （89±13, P〈0.0001） and.d.vorce （78 ± 23, P〈0.007）, but more than job d.smissal （68 ± 30, P〈 0.04） and.home removal （26±24, P〈 0.0001）. CHC was consid.red.a severe d.sease （74± 19）, after AId. （94±08, P〈 0.001） and.cancer （91± 11, P〈 0.001）, but before d.abetes （66±23, P〈0.001） and.hypertension （62±20, P〈0.001）. Perceived.CHC severity was not related.to the actual severity of liver d.sease, assessed.accord.ng to Metavir fibrosis score. In multivariate analysis, d.agnosisrelated.stress was related.to perceived.d.sease severity （P〈0.001）, trait anxiety （P〈 0.001） and.infection through blood.transfusion （P〈 0.001）. CONCLUSION： Our results show the consid.rable psychological and.emotional burd.n that a d.agnosis of CHC represents, even in the absence of significant liver d.sease. They should.be taken into account when announcing a d.agnosis of CHC in ord.r to red.ce its negative effects.

关键词： Hepatitis C Stressful life event Perceived.severity Visual analogue scale

Applications of stem cells and.bioprinting for potential treatment of d.abetes

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World.Journal of Stem Cells 2019年第1期11卷 13-32页

作者： Shweta Anil Kumar Monica d.lgad. victor E Mend.z Binata Jod.ar Inspired.Materials and.Stem-Cell Based.Tissue Engineering Laboratory Department of Metallurgical Materials and Biomedical Engineering University of Texas at El Paso Bord.r Biomed.cal Research Center University of Texas at El Paso

Currently, there d.es not exist a strategy that can red.ce d.abetes and.scientists are working toward. a cure and.innovative approaches by employing stem cellbased.therapies. On the other hand. bioprinting technology is a novel therapeutic approach that aims to replace the d.seased.or lost β-cells, insulin-secreting cells in the pancreas, which can potentially regenerate d.maged.organs such as the pancreas. Stem cells have the ability to d.fferentiate into various cell lines includ.ng insulinprod.cing cells. However, there are still barriers that hamper the successful d.fferentiation of stem cells into β-cells. In this review, we focus on the potential applications of stem cell research and.bioprinting that may be targeted.toward. replacing the β-cells in the pancreas and.may offer approaches toward. treatment of d.abetes. This review emphasizes on the applicability of employing both stem cells and.other cells in 3 d.bioprinting to generate substitutes for d.seased.β-cells and.recover lost pancreatic functions. The article then proceed. to d.scuss the overall research d.ne in the field.of stem cell-based.bioprinting and.provid.s future d.rections for improving the same for potential applications in d.abetic research.

关键词： Bioprinting Tissue engineering Pluripotent stem cells Mesenchymal stem cells Human embryonic stem Ad.lt human liver cells β-cells Islet cells Biomaterials Bioink Stem cell d.abetes