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Influence of Induction Motor Design Data on Effects of Cage Asymmetry

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journal of Energy and Power Engineering 2013年第8期7卷 1586-1591页

作者： Alejandro Fernandez gomez Tadeusz j. Sobczyk Institute on Electromechanical Energy Conversion Cracow University of Technology Krak6w 31-155 Poland

The purpose of this paper is to analyze influence of design data on a component （1 - 2s）~ in stator currents of induction motors, mainly used for cage fault diagnosis. This paper shows that such an approach does not always lead to a correct outcome. The considerations are based on a ＂classical＂ model of induction motors extended to cage asymmetry by introducing cage asymmetry factors ko~ and ka. It has been found that in order to estimate the level of the component （1 - 2s）7~, it is enough to know the pole-pair number ＂p＂ and the number of rotor slots ＂N＂. The main objective of the paper is to provide engineers with simple qualitative prediction of effects due to cage faults for various motors when information on design data is very limited.

关键词： Induction motor rotor cage asymmetry cage motor diagnosis motor current signature analysis.

Antioxidant and immunomodulatory effects of Viusid in patients with chronic hepatitis C

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World journal of Gastroenterology 2010年第21期16卷 2638-2647页

作者： Eduardo Vilar gomez Yadina Martinez Perez hector Vega Sanchez Gretel Riveron Forment Enrique Arus Soler Luis Calzadilla Bertot Ali Yasells Garcia Maria del Rosario Abreu Vazquez Licet Gonzalez Fabian Department of Hepatology National Institute of GastroenterologyHavana 10400Cuba Department of Gastroenterology National Institute of GastroenterologyHavana 10400Cuba Department of Immunology National Institute of GastroenterologyHavana 10400Cuba Department of Oxidative Stress National Genetic CenterHavana 10400Cuba Department of Biostatistics National Institute of GastroenterologyHavana 10400Cuba Department of Pathology Institute of GastroenterologyHavana 10400Cuba

AIM:To investigate the efficacy of Viusid,a nutritional supplement,as an antioxidant and an immunomodulator in patients with chronic hepatitis ***:Sixty patients with chronic hepatitis C who were non-responders to standard antiviral treatment were randomly assigned to receive Viusid(3 sachets daily,n=30) or placebo(n=30) for 24 *** primary outcome was the change in serum malondialdehyde and 4-hydroxyalkenals(lipid peroxidation products).Secondary outcomes were changes in serum tumor necrosis factor-α(TNF-α),interferon-γ(IFN-γ) and interleukin-10(IL-10).RESULTS:Statistically significant reductions in serum 4-hydroxyalkenals and malondialdehyde levels were observed in both groups in comparison with pretreatment values,but the patients who received Viusid showed a more marked reduction as compared with the control group(P=0.001).TNF-α levels significantly increased from 6.9 to 16.2 pg/mL(P< 0.01) in the patients who received placebo in comparison with almost unchanged levels,from 6.6 to 7.1 pg/mL(P=0.26),in the patients treated with Viusid(P=0.001).In addition,IL-10 levels were markedly increased in the patients treated with Viusid(from 2.6 to 8.3 pg/mL,P=0.04) in contrast to the patients assigned to placebo(from 2.8 to 4.1 pg/mL,P=0.09)(P=0.01).Likewise,the administration of Viusid markedly increased mean IFN-γ levels from 1.92 to 2.89 pg/mL(P< 0.001) in comparison with a reduction in mean levels from 1.80 to 1.68 pg/mL(P=0.70) in the placebo group(P< 0.0001).Viusid administration was well ***:Our results indicate that treatment with Viusid leads to a notable improvement of oxidative stress and immunological parameters in patients with chronic hepatitis C.

关键词： Antioxidant therapy Chronic hepatitis C Cytokines Immunomodulatory therapy Nutritional supplement Oxidative stress

How to boost the effects of exercise to favor traumatic brain injury outcome

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Sports Medicine and Health Science 2022年第3期4卷 147-151页

作者： Fernando gomez-Pinilla Natosha M.Mercado Department of Integrative Biology&Physiology University of California at Los Angeles(UCLA)Los AngelesCA90095USA Department of Neurosurgery UCLA Brain Injury Research CenterUniversity of California at Los AngelesLos AngelesCA90095USA

Physical rehabilitation is an effective therapy to normalize weaknesses encountered with neurological disorders such as traumatic brain injury(TBI).However,the efficacy of exercise is limited during the acute period of TBI because of metabolic dysfunction,and this may further compromise neuronal *** we discuss the possibility to normalize brain metabolism during the early post-injury convalescence period to support functional plasticity and prevent long-term functional *** BDNF possesses the unique ability to support molecular events involved with the transmission of information across nerve cells through activation of its TrkB receptor,the poor pharmacokinetic profile of BDNF has limited its therapeutic *** flavonoid derivative,7,8-dihydroxyflavone(7,8-DHF),signals through the same TrkB receptors and results in the activation of BDNF signaling *** discuss how the pharmacokinetic limitations of BDNF may be avoided by the use of 7,8-DHF,which makes it a promising pharmacological agent for supporting activity-based rehabilitation during the acute post-injury period after *** turn,docosahexaenoic acid(C22:6n-3;DHA)is abundant in the phospholipid composition of plasma membranes in the brain and its action is important for brain development and *** is a major modulator of synaptic membrane fluidity and function,which is fundamental for supporting cell signaling and synaptic *** influences DHA function by normalizing DHA content in the brain,such that the collaborative action of exercise and DHA can be instrumental to boost BDNF function with strong therapeutic potential for reducing the deleterious effects of TBI on synaptic plasticity and cognition.

关键词： Exercise Traumatic brain injury Brain Synaptic plasticity DHA BDNF

High pressure responsive luminescence of flexible Eu^(3+) doped PVDF fibrous mats

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journal of Materials Science & Technology 2021年第7期66卷 103-111页

作者： Carlos Hernandez San tosh K.Gupta jose P.Zuniga jorge Vidal Rene Galvan hector Guzman Lilian Chavez Karen Lozano Yuanbing Mao Department Department of Chemistry University of Texas Rio Grande Valley1201 West University DriveEdinburgTX 78539USA Radiochemistry Division Bhabha Atomic Research CentreTrombayMumbai400085USA Department of Electrical Engineering University of Texas Rio Grande ValleyEdinburgTX 78539USA Department of Chemistry Illinois Institute of Technology3105 South Dearborn StreetChicagoIL 60616USA

Exploring lanthanide doped materials and their high-pressure optical properties is important from the perspective of designing pressure sensors, piezoelectric materials, scintillators, and optoelectronic devices, just to mention a few. Understanding the high-pressure optical properties of polymeric fibrous mats provides significant advantages in terms of flexibility, tunability, facile processability, and malleability. In this work, we have developed flexible polyvinylidene difluoride(PVDF) fibrous mats doped with an Eu^(3+) source of Eu(NO_(3))_(3)·5H_(2)O(EN-PF) or Eu_(2)(SO_(4))_(3)(ES-PF) by a Forcespinning■ method. Microstructural analysis of these two systems indicates that Eu(NO_(3))_(3)·5H_(2)O and Eu_(2)(SO_(4))_(3) are homogeneously distributed and dispersed into the PVDF matrix. Fiber formation promotes a β-phase PVDF. Eu^(3+) doping increases the β-phase. Its fraction is larger for the ES-PF mats. To understand their high-pressure optical properties, their photoluminescence spectra have been taken at various pressures up to 58 GPa in a diamond anvil cell. High-pressure luminescence illustrates a clear change in asymmetry ratio, peak intensity, peak breadth, color coordinate, and color temperature of Eu^(3+) ions from both EN-PF and ES-PF with a different extent of changes. Specifically, Eu^(3+) ions in the ES-PF mats switch from asymmetric to symmetric environment as pressure increases. Those in the EN-PF mats present symmetric environment for all tested pressures. Both of the Eu^(3+) doped PVDF systems present irreversible changes. Therefore,the EN-PF fibrous mats present an opportunity to make pressure induced red-orange-yellow tunable phosphors for multifunctional applications.

关键词： Polyvinylidene difluoride Europium Fiber High pressure Luminescence

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遗传性短QT综合征的研究进展

中华心血管病杂志 2019年第5期47卷 413-416页

作者：石少波 hector Barajas-Martinez 胡丹武汉大学人民医院心内科武汉大学心血管病研究所心血管病湖北省重点实验室 430060 美国宾夕法尼亚州温纽伍德市兰肯瑙医学研究所 19096

短QT综合征是以QT间期缩短、心脏性猝死高风险为特征的遗传性心脏离子通道病。它属于常染色体显性遗传,发病罕见,与编码钾通道和钙通道的基因突变有关,基因突变导致的IKr、IKs、IK1增大和ICa,L功能丢失,使净外向电流增加或内向电流减少... 详细信息

短QT综合征是以QT间期缩短、心脏性猝死高风险为特征的遗传性心脏离子通道病。它属于常染色体显性遗传,发病罕见,与编码钾通道和钙通道的基因突变有关,基因突变导致的IKr、IKs、IK1增大和ICa,L功能丢失,使净外向电流增加或内向电流减少,复极加速,动作电位时程缩短和复极离散度增加,最终触发室性心动过速/心室颤动(VT/VF)。植入式心脏复律除颤器是唯一有效的防治心脏性猝死的手段,奎尼丁和索他洛尔通过延长有效不应期和QT间期,可有效预防VT/VF。

关键词：短QT综合征心脏性猝死流行病学

High-quality-factor tantalum oxide nanomechanical resonators by laser oxidation of TaSe2

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Nano Research 2015年第9期8卷 2842-2849页

作者： Santiago j. CartamiI-Bueno Peter G. Steeneken Frans D. Tichelaar Efren Navarro-Moratalla Warner j. Venstra Ronald van Leeuwen Eugenio Coronado Herre S.j. van der Zant Gary A. Steele Andres Castellanos-gomez Kavli Institute of Nanoscience Delft University of Technology Lorentzweg 1 2628 CJ Delft The Netherlands Kavli Institute of Nanoscience Delft University of Technology National Centre for HREM Lorentzweg 1 2628 CJ Delft The Netherlands Instituto Ciencia Molecular (ICMol) Univ. Valencia C/Catedrdtico Jos@ Beltrdn 2 E-46980 Paterna Spain

Controlling the strain in two-dimensional （2D） materials is an interesting avenue to tailor the mechanical properties of nanoelectromechanical systems. Here, we demonstrate a technique to fabricate ultrathin tantalum oxide nanomechanical resonators with large stress by the laser oxidation of nano-drumhead resonators composed of tantalum diselenide （TaSe2）, a layered 2D material belonging to the metal dichalcogenides. Before the study of their mechanical properties with a laser interferometer, we verified the oxidation and crystallinity of the freely suspended tantalum oxide using high-resolution electron microscopy. We demonstrate that the stress of tantalum oxide resonators increases by 140 MPa （with respect to pristine TaSe2 resonators）, which causes an enhancement in the quality factor （14 times larger） and resonance frequency （9 times larger） of these resonators.

关键词： TaSe2,tantalum oxide,mechanical resonators,laser oxidation,optical interferometer,high quality factor

Noisy environments:untangling the role of anthropogenic noise on bird species richness in a Neotropical city

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Avian Research 2020年第3期11卷 258-264页

作者： Cecilia Odette Carral-Murrieta Michelle Garcia-Arroyo Oscar H.Marin-gomez j.Roberto Sosa-Lopez Ian MacGregor-Fors Red de Ambiente y Sustentabilidad Instituto de EcologíaA.C.(INECOL)Carretera antigua a Coatepec 351El Haya91070 XalapaVeracruzMexico Centro Interdisciplinario de Investigación para el Desarrollo Integral Regional Unidad Oaxaca(CIIDIR) Instituto Politécnico NacionalOaxacaMexico Dirección de Cátedras Consejo Nacional de Ciencia y Tecnología(CONACYT)Mexico CityMexico

Background:Among urban stimuli,anthropogenic noise has been identified to be one of the behavioral drivers of species that rely on acoustic signals for *** have shown both species‑specific and assemblage responses to urban noise,ranging from the modulation of their acoustic frequencies and spatiotemporal adjustments to declines in species *** this study,we assessed the citywide relationship between two anthropogenic noise variables(noise levels recorded during bird surveys and daily average noise levels)and vegetation cover with bird species ***:This study was conducted in the city of Xalapa(Mexico)through a 114 citywide point‑count *** recorded bird communities at each sampling *** measured noise levels using a sound level meter while performing point‑***,we generated a map of average daily noise of the city using an array of 61 autonomous recording units distributed across the city of Xalapa and calculated daily noise levels for the 114 *** ran a linear model(LM)to assess potential relationships between both point‑count and daily(24 h)noise values and vegetation cover with bird ***:Results from the LM show:(1)a negative relationship between maximum point‑count noise and avian species richness,(2)no relationship between 24 h noise and bird species richness,and(3)a positive relationship between vegetation cover and bird species ***:Results provide evidence that decreases in urban bird species richness do not necessarily imply the permanent absence of species,suggesting that birds can temporarily fly away from or avoid sites when noisy,become cryptic while noisy events are occurring,or be undetected due to our inability to record them in the field during noisy events.

关键词： Avian ecology Bird communication Noise pollution Species richness Urban ecology

Projections of Incidence, Prevalence and Mortality from Melanoma in Spain

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journal of Cosmetics, Dermatological Sciences and Applications 2013年第2期3卷 1-6页

作者： Milagros Bernal Dyego L. B. Souza German gomez Francisco j. gomez Atención Primaria de Salud Zaragoza Spain Universidad de Rio Grande Port Alegre Brazil Universidad de Zaragoza Zaragoza Spain

Objective: The incidence and mortality rates for cutaneous melanoma (CM) have increased markedly in the last few years. As such, the aim of this study was to forecast their progression in Spain up until 2022. Design: A prospective epidemiological study using the Miamod technique. The primary data source was the mortality statistics released by the National Statistics Institute. Study selection: The MIAMOD method was used. Data extraction: Cases of death due to general and melanoma-related mortality in Spain between 1998 and 2007. Results: In men, the incidence is expected to increase from 11.85 (adjusted: 8.52) to 14.79 (adjusted: 9.43) per 100,000 inhabitants over the period 1998-2022. Similarly, the mortality is expected to increase slightly from 5.84 (adjusted: 4.12) to 7.19 (adjusted: 4.49) per 100,000 inhabitants, and the prevalence from 73.72 (adjusted: 52.31) to 95.46 (adjusted: 60.02) per 100,000 inhabitants over the same period. In women, the incidence is expected to increase from 3.79 (adjusted: 3.04) to 6.46 (adjusted: 4.21) per 100,000 inhabitants between 1998 and 2022, although this increase is not statistically significant. The mortality is expected to increase from 1.67 (adjusted: 1.24) to 2.98 (adjusted: 1.86) per 100,000 inhabitants, and the prevalence from 50.04 (adjusted: 44.54) to 84.81 per (adjusted: 56.18) 100,000 inhabitants over the same period. Conclusions: Primary and secondary prevention programs for this disease must be maintained.

关键词： Projections Cutaneous Melanoma Incidence Mortality

Scalable and low-cost fabrication of flexible WS_(2) photodetectors on polycarbonate

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npj Flexible Electronics 2022年第1期6卷 226-234页

作者： jorge Quereda Sruthi Kuriakose Carmen Munuera Federico j.Mompean Abdullah M.Al-Enizi Ayman Nafady Enrique Diez Riccardo Frisenda Andres Castellanos-gomez GISC Departamento de Física de MaterialesUniversidad Complutense de MadridMadridSpain Materials Science Factory Instituto de Ciencia de Materiales de Madrid(ICMMCSIC)28049 MadridSpain Department of Chemistry College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia Nanotechnology Group USAL–NanolabUniversidad de Salamanca37008 SalamancaSpain

We present a low-cost and easy-to-implement technique to fabricate large-area WS_(2) photodetector devices onto transparent and flexible polycarbonate *** method relies on the deposition of large-area(in the cm scale)thin films(~30 nm thick)of WS_(2) by a recently introduced abrasion-induced *** electrical contacts are then deposited by thermal evaporation through a shadow *** photodetectors present well-balanced performances with an good trade-off between responsivity(up to 144 mA/W at a source-drain voltage of 10 V and illumination power of 1μW)and response time(down to~70µs)and a detectivity value of 10^(8) *** found that the devices perform very reversibly upon several illumination and straining cycles and we found a moderate device-to-device variation.

关键词： drain illumination cost