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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 727-740页

作者： Chengkai Fan na Zhang Bei Jiang Wei victor Liu Department of Civil and Environmental Engineering University of AlbertaEdmontonAlbertaT6G 2E3Canada Department of Mathematical and Statistical Sciences University of AlbertaEdmontonAlbertaT6G 2G1Canada

Ore production is usually affected by multiple influencing inputs at open-pit ***,the complex nonlinear relationships between these inputs and ore production remain *** becomes even more challenging when training data(*** haulage information and weather conditions)are *** machine learning(ML)algorithms,deep neural network(DNN)is a superior method for processing nonlinear and massive data by adjusting the amount of neurons and hidden *** study adopted DNN to forecast ore production using truck haulage information and weather conditions at open-pit mines as training *** the prediction models were built,principal component analysis(PCA)was employed to reduce the data dimensionality and eliminate the multicollinearity among highly correlated input *** verify the superiority of DNN,three ANNs containing only one hidden layer and six traditional ML models were established as benchmark *** DNN model with multiple hidden layers performed better than the ANN models with a single hidden *** DNN model outperformed the extensively applied benchmark models in predicting ore *** can provide engineers and researchers with an accurate method to forecast ore production,which helps make sound budgetary decisions and mine planning at open-pit mines.

关键词： Oil sands production Open-pit mining Deep learning Principal component analysis(PCA) Artificial neural network Mining engineering

Moving of a submarine under an ice cover in fluid of finite depth

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Journal of Hydrodynamics 2019年第3期31卷 562-569页

作者： Alexandra V. Pogorelova Vitali L. Zemlyak victor M. Kozin Sholom-A leichem Priamursky State University Birobidzhan Russia Institute of Machining and Metallurgy FEB RAS Komsomolsk-na-Amure Russia

The influence of a basin depth on ice cover deflections, when a submarine moves under it in fluid, is experimentally and theoretically analyzed. For a theoretical research the ice cover is modelled by an elastic floating plate, and the submarine is modelled by a source-sink system in a fluid flow. The problem is solved by means of asymptotic analysis and integral transformations. The experimental study is conducted with submarine models in the pool with the sizes L*B*H= 10m*3m*lm . The ice cover for experiments is modelled in two ways. The first way is the thin ice plate received by freezing of the surface layer of water at low temperatures. In the second case the rubber sheet floating on a reservoir surface is used. The special velocity (the velocity at which maximum values of the wave height are reached) is analyzed. It is obtained that the decrease of the basin depth leads to decrease of the special speed. For small speeds (less than the special speed) there is the fact that the basin depth decrease leads to the increase of the height of the flexural-gravity wave.

关键词： Ice cover submarine flexural gravity wave source-sink system

A review of potential mechanisms and uses of SGLT2 inhibitors in ischemia-reperfusion phenomena

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World Journal of Diabetes 2022年第9期13卷 683-695页

作者： victor Quentin Manveer Singh Lee S Nguyen Intensive Care Medicine CMC Ambroise ParéNeuilly-sur-Seine 92200France Research and Innovation CMC Ambroise ParéNeuilly-sur-Seine 92200France

Recently added to the therapeutic arsenal against chronic heart failure as a first intention drug,the antidiabetic drug-class sodium-glucose cotransporter-2 inhibitors(SGLT2i)showed efficacy in decreasing overall mortality,hospitalization,and sudden death in patients of this very population,in whom chronic or acute ischemia count among the first ***,this benefit was observed independently from diabetic status,and benefited both preserved and altered ventricular ejection *** feature,observed in several large randomized controlled trials,suggests additional effects from SGLT2i beyond isolated glycemia ***,both in-vitro and animal models suggest that inhibiting the na+/H+exchanger(NHE)may be key to preventing ischemia/reperfusion injuries,and by extension may hold a similar role in ischemic damage control and ischemic ***,several other mechanisms may be explored which may help better target those who may benefit most from SGLT2i *** of a large therapeutic margin with few adverse events,ease of prescription and potential pharmacological efficacity,SGLT2i could be candidate for wider *** this review,we aim to summarize all evidence which link SGLT2i and ischemia/reperfusion injuries modulation,by first listing known mechanisms,including metabolic switch,prevention of lethal arrythmias and others,which portend the latter,and second,hypothesize how the former may interact with these mechanisms.

关键词： SGLT2 inhibitors Ischemia-reperfusion injuries Sodium-proton exchanger Myocardial ischemia Immunomodulation

Electroreduction of Tungsten Oxide（VI） in Molten Salts with Added Metaphosphate

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Chemical Research in Chinese Universities 2013年第4期29卷 771-775页

作者： MALYSHEV victor GAB Angelina POPESCU Ana-Maria CONSTANT1N Virgil Faculty of Chemistry & Technology National Technical University of Ukraine "Kyiv Polytechnical Institute " Kyiv 05056 Ukraine" Open International University of Human Development of Ukraine Kyiv 04071 Ukraine Laboratory of Molten Salts Ilie Murgulescu" Institute of Physical Chemistry of the Romanian Academy Bucharest 006021 Roumania

Tungstate ions WO4^2- are not electrochemically active in chloride melts. Upon introduction of PO3 ions into the melt, two waves appear in the voltammograms at potentials -0.1-- -0.2 V and -0.3-- -0.5 V vs. Pb/Pb2＋ reference electrode. With a PO3- concentration ratio of 0.01〈[PO3-]/[WO42-]〈0.18, the potentiostatic electrolysis product of WO42 at the above mentioned potentials is metallic tungsten; a naPO3 concentration increase for ratios [PO3-]/[WO42-]〉〉0.18 results in tungsten phosphide in electrolysis product. Cyclic voltammograms and dependence of half-peak potentials on electrode polarization rate indicate the irreversible character of the electrode process. Elec- trode process modeling allows us to state that the first wave in the voltammogram of KC1-naC1-na2WOa-naPO3 sys- tem corresponds to tungsten oxychlorides discharge while the second wave appears due to the discharge of di- tungstate ions. In the voltammograms of na2WOa-naPO3 melts, reduction wave was observed at -1.1-- -1.2 V po- tentials. Proportionality of limiting current to naPO3 concentration, constancy of ld/V1/2 ratio, and IJnFc constant ki- netic value equal to （8.3--9.5）×10-5 cm/s for steady-state wave indicate that electrode process rate is limited by elec- trochemically active particle diffusion to the electrode. nascent ditungstate ions become electrochemically active in the overall electrode process. Charge transfer stage is reversible.

关键词： Tungsten oxide Electroreduction Molten salt Cyclic voltammetry

Relation of coronary collateral circulation with epicardial fat volume in patients with stable coronary artery disease

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Journal of Geriatric Cardiology 2013年第4期10卷 344-348页

作者： Aslm Enhos Irfan Sahin Mehmet Mustafa Can Ibrahim Biter Mustafa Hakan Dinckal victor Serebruany Bagc(i)lar Research and Education Hospital Cardiology Department Bagc(i)lar 34800 Istanbul Turkey

OBJECTIVE: To investigated the relationship between epicardial fat volume (EFV) and coronary collateral circulation (CCC) in patients with stable coronary artery disease (CAD)。 METHODS: The study population consisted of 152 consecutive patients with CAD who underwent coronary angiography and were found to have at least 95% significiant lesion in at least one major coronary artery。 EFV was assessed utilizing 64-multislice computed tomography。 The patients were classifield into impaired CCC group (Group 1, Rentrop grades0-1, n =58), or adequate CCC (Group 2, Rentrop grades 2-3, n = 94)。 RESULTS: The EFV values were significantly higher in paitients with adequate CCC than in those with impaired CCC。 In multivariate logistic regression analysis, EFV (OR = 1.059;95% CI: 1.035-1.085; P = 0.001); and presence of angina were independent predictors of adequate CCC。 In receiver-operating characteristic curve analysis, the EFV value > 106.5 mL yielded an area under the curve value of 0.84, with the test sensitivity of 49.3%, and with 98.3% specifity。 CONCLUSIONS: High EFV, and the presence of angina independently predict adequate CCC in patients with stable coronary artery disease。 This association offers new diagnostic opportinities to assess collateral flow by conventional ultrasound techniques。

关键词： Angına Collateral circulation Coronary artery disease Epicardial adipose tissue

Insights on Blood Cytokines Production under Different <i>In Vitro</i>Mycobacterial Antigens in Tuberculosis Intestinal Parasites Co Infected Patients

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Advances in Microbiology 2018年第3期8卷 161-174页

作者： Renan Jeremias da Silva Fernanda C. Q. Mello Janaína A. Leung Antonio Henrique Almeida de Moraes Neto Leila de Souza Fonseca Helio Ribeiro de Siqueira Health Care victor Vala and CSEGSF Team Maria Helena Féres Saad Laboratory of Cellular Microbiology Oswaldo Cruz Institute (IOC) Fiocruz Rio de Janeiro Brazil Federal University of Rio de Janeiro Clementino Fraga Filho Hospital Rio de Janeiro RJ Brazil Laboratory of Innovations in Therapies Teaching and Bioproducts Oswaldo Cruz Institute (IOC) Fiocruz Rio de Janeiro Brazil Rio de Janeiro State University Pedro Ernesto Hospital Rio de Janeiro Brazil victor Vala Family Clinic and Health Care-School Germano Silval Farias (CSEGSF) ENSP/Fiocruz Rio de Janeiro Brazil

Background: The concomitant presence of intestinal parasite infections (IP) and tuberculosis (TB) has relevance. M. tuberculosis immune response is associated with type 1 T helper cell (Th1) while IP is associated with type Th2 cell. However, there are several contradictory reports on cytokine production under coinfection and this could be in association to the mycobacterial antigens used in the studies. Aim: To get insight into the effects of different M. tuberculosis-specific antigens (ESAT-6/CFP-10 and 38 kda/CFP-10) in generating of appropriate cytokines on peripheral blood mononuclear cells of IPTB co infected patients. Method: ELISA assessed IFN-γ and other 16 cytokines production and plasm IgE. In 18 months, we documented demographic, economic, clinical characteristics and IP frequency in individuals from Brazil. Results: An overall 10/35 (28.5%) were IPTB co infected and 40/76 (52.6%;p = 0.024) asymptomatic intestinal parasite infected community controls (IPCC). Endo-limax nana (40%) and Entamoeba coli (22%), were the most nonpathogenic protozoan identified and Entamoeba histolytica, Giardia intestinalis, Ascaris lumbricoides and Strongyloides stercoralis were the pathogenic species (40%). IgE was higher in IPCC (p = 0.036). Cytokine profiles were significantly biased toward a Th2 type IL-5 (p = 0.001) and IL-13 (p = 0.033), pro-inflammatory GM-CSF (p = 0.019) and borderline lower IL-1β in IPTB, all associated with ESAT-6/CFP-10, while IL-7 was borderline lower, but 38 kda/CFP-10 associated;as well as IL-8 higher (p ial discrepancy in Th1/Th2 response, is associated with the antigen priming cells.

关键词： Mycobacterium tuberculosis Intestinal Parasites Mycobacterial Antigens IgE Cytokines

腹水和低钠血症对肝移植手术中输血量和升压药应用的影响

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山东医药 2008年第19期48卷 14-15页

作者：杜斌 victor W Xia 昆明医学院第二附属医院云南昆明650101 加州大学洛杉矶分校医疗中心

目的探讨术前并存腹水或低钠血症对不同MELD评分患者在肝移植手术中输血量和升压药应用的影响。方法192例行肝移植手术患者,按术前MELD评分、有无腹水或低钠血症分组,记录并比较肝移植手术中浓缩红细胞,冰冻血浆的输入量及升压药使用情... 详细信息

目的探讨术前并存腹水或低钠血症对不同MELD评分患者在肝移植手术中输血量和升压药应用的影响。方法192例行肝移植手术患者,按术前MELD评分、有无腹水或低钠血症分组,记录并比较肝移植手术中浓缩红细胞,冰冻血浆的输入量及升压药使用情况。结果高MELD(>30)评分组与低MELD(≤30)评分组比较,在手术中需输入更多的血液和使用升压药维持循环平稳;不同血清钠组(nana≥130 mmol/L)在手术中输血量和升压药使用情况无明显差异;而并存腹水的患者,不论MELD评分及MELD+A高低,与非腹水组相比,在手术中均需输入更多的血液和更高的升压药使用率。结论虽然腹水和低钠血症均是衡量肝脏疾病严重性的指标,但仅有腹水这一指标影响患者在肝移植手术中的循环平稳。

关键词：腹水低钠血症肝移植升压药输血量

Stressed-Deformed State of Ice Crossings at the Surface Reinforcement of Composite Materials

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Journal of Marine Science and Application 2020年第3期19卷 430-435页

作者： Xiaolong Bai Vitaliy Zemlyak Alexey Vasilyev victor Kozin School of naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Department of Technical Sciences Sholom-Aleichem Priamursky State UniversityBirobidzhan 679015Russia Laboratory Number 1 Institute of Machining and Metallurgy Far Eastern Branch Russian Academy of SciencesKomsomolsk-na-Amure 681005Russia

Ice crossings have been used for several ***,due to the active development of the Arctic shelf,supplies and minerals are provided and transferred on special transports on the surface of ice ***,ice crossings across rivers are used to reduce the length of transport *** methods of increasing the load bearing capacity of ice are ice freezing from above,ice freezing from below,and ice strengthening through a wooden copepod *** experience shows that the physical and mechanical properties of ice covers are unreliable and changeable in time and strongly depend on various external ***,ice covers should be strengthened through alternative ***,predicting the bearing capacity of ice crossings and exploring methods for their strengthening are *** this study,we consider the results of experimental and numerical studies on the bearing and deformation capacity of ice beams upon destruction from pure *** pure bending,ice breaks down in the ice crossing when transports move along *** were carried out with a specified reinforcement *** results of the model experiments were compared with numerical calculations in the ANSYS software *** on ice beams reinforced with various composite materials were also *** of samples in all cases occurred as a result of the formation of extensive cracks in the ice caused by the bending moment in the middle of the beam *** on the experimental and numerical research results,the use of a surface reinforcement in ice with various materials can increase the bearing capacity from 65%to 99%for this reinforcement scheme.

关键词： Ice beam Surface reinforcement Carrying capacity Numerical research Criterion of strength

尼日利亚北部非造山碱性杂岩的地质特征和形成时代：对岩石成因和构造演化的制约

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尼日利亚北部非造山碱性杂岩的地质特征和形成时代：对岩石成因和...

作者： victor Ikechukwu Vincent 中国地质大学

学位级别：硕士

尼日尔和尼日利亚年轻花岗岩省,是全球非造山碱性环状花岗岩带的典例,其年龄由北向南逐渐变新(470-140 Ma)。本文对来自尼日利亚年轻花岗岩省(na YG)的六个非造山正长岩-花岗岩杂岩体(Banke、daura、Dutse、Dutsen Wai、Guraka和Zuku)... 详细信息

尼日尔和尼日利亚年轻花岗岩省,是全球非造山碱性环状花岗岩带的典例,其年龄由北向南逐渐变新(470-140 Ma)。本文对来自尼日利亚年轻花岗岩省(na YG)的六个非造山正长岩-花岗岩杂岩体(Banke、daura、Dutse、Dutsen Wai、Guraka和Zuku)进行了综合研究,以制约其岩浆源区、稀有金属矿化潜力和构造意义。岩石主要由正长岩、花岗斑岩、钠铁闪石霓石花岗岩和黑云母花岗岩组成。所有岩性均具有高的碱度,HFSE含量,Ga/Al比值和锆饱和温度(776-1161C,平均为932C),类似于典型A型花岗岩。daura和Dutse环状杂岩体的Nd-Pb-Hf同位素组成(εNd(t)=-2.9至+1.5;Pb/Pb=17.82-19.56;εHf(t)=-3.8至16.7)表明原始岩浆源于略亏损的OIB型地幔。矿物化学分析表明初始熔体具有相对还原到弱氧化的氧逸度。daura角闪石正长岩主要由60%以上的碱性长石组成,具有高的Eu/Eu*(>1)和Ba/Zr比值(>3.5)和堆晶结构特点,为碱性长石堆晶岩。然而,daura和Dutse杂岩体其他碱性花岗岩的形成可能与残余熔体不同程度的分离结晶和地壳混染作用有关。na YG中北部杂岩体(Banke、Dutsen Wai、Guraka和Zuku)钠铁闪石霓石花岗岩锆石εHf(t)值为-6.0至-0.79,高于花岗斑岩(-9.57至-7.67)和黑云母花岗岩(-9.49至-5.86),表明过碱性花岗岩可能是地幔熔体经中度地壳混染的产物。Banke和Dutsen Wai黑云母花岗岩中泛非期继承锆石(600-610 Ma)的存在及低的全岩Nb/U和Nb/Ta比值,表明它们的形成可能与壳幔熔体相互作用有关。地壳物质混染也增加了残余熔体中的稀有金属含量,并导致Banke花岗斑岩和黑云母花岗岩和Dutsen Wai黑云母花岗岩中的Nb、Sn和硫化物矿化。daura角闪石正长岩和黑云母花岗岩分别形成于324±1 Ma和321±3 Ma,而Dutse花岗岩类具有两期年龄,为～264 Ma和232 Ma。这些年龄均早于尼日利亚年轻花岗岩省其它碱性环状杂岩,这一结果更新了na YG花岗岩省重最古老的碱性杂岩的年龄记录(此前报道的年龄为214 Ma)。daura杂岩的年龄与较老花岗岩省(Nr YG)最南端的Zidner杂岩体(～330 Ma)的年龄十分接近,反映了Nr YG和na YG花岗岩省之间的重要联系。锆石U-Pb定年获得Banke花岗斑岩形成于180±1 Ma,Dutsen Wai黑云母花岗岩形成于177±3 Ma,Gurak钠铁闪石霓石花岗岩形成于232±2 Ma,Zuku钠铁闪石花岗岩形成于195±1 Ma。这些年龄结果指示了na YG花岗岩省中北部在局部地区存在碱性岩浆侵位的东西向年龄迁移规律。纵观尼日尔和尼日利亚花岗岩省碱性环状杂岩体的时空分布,尽管存在局部小范围的时空交叉,但从北到南的线性年龄迁移规律仍非常明显。这种岩浆迁移就位机制可能与区域岩石圈深断裂再次活化有关。

关键词：非造山碱性岩浆作用尼日利亚年轻花岗岩省 Banke-daura-DutsenWai-Dutse-Guraka-Zuku杂岩体

Refractive index measurement of dielectric samples using highly focused radially polarized light(Invited Paper)

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Chinese Optics Letters 2017年第3期15卷 12-15页

作者： Guadalupe López-Morales victor-Manuel Rico-Botero Rafael Espinosa-Luna Qiwen Zhan GIPYS Laboratory Centro de Investigaciones en Optica A. C. León Gto 37150 México Department of Electro-Optics and Photonics University of Dayton Dayton OH 45469 USA

In this Letter, a refractive index measurement of a dielectric sample using highly focused radially polarized light is reported. Through imaging analysis of the optical field at the pupil plane of a high numerical aperture （na） objective lens reflected by the sample under study, the Brewster angle is found. Employing a high na objective lens allows the measurement of multiple angles of incidence from 0° to 64° in a single shot. The refractive index of the sample is estimated using the measured Brewster angle. The experimental results are compared with the theoretical images computed with the Fresnel theory, and a good agreement is obtained.

关键词： high Refractive index measurement of dielectric samples using highly focused radially polarized light