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Conceptual design and optimization of a tilt-rotor micro air vehicle

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Chinese Journal of Aeronautics 2019年第2期32卷 369-381页

作者： m.HASSANALIAN R.salazar A.ABDELKEFI Department of mechanical and Aerospace Engineering New Mexico State University Department of mechanical Engineering New Mexico Institute of Mining and Technology

The conceptual design and optimization of a tilt-rotor micro Air Vehicle(mAV) for a well-defined mission are performed. The objective of this design cycle is to decrease the design time in order to efficiently create a functional tilt-rotor drone. A flight mission is firstly defined for a tiltrotor mAV performing hovering and cruise flight scenarios. Secondly, a complex wing shape is chosen and modeled in order to determine the final shape. The initial shape is scaled in order to acquire an arbitrary wingspan of one meter. For the specific area and wingspan, the aspect ratio of the designed wing shape is found to be equal to 2.32. Thirdly, a constraint analysis of the mAV is performed by using an energy balance analysis for six different flight scenarios. This analysis yields the required power loading and wing loading. Fourthly, the weight of the vehicle is estimated using both statistical and computational methods. After estimating the total weight and the wing loading of the mAV, the surface of the wing is determined, yielding a final wingspan of 0.76 m. Subsequently, considering the total weight of the designed mAV, the needed lift coefficient is ***, using the lift coefficient in conjunction with XLFR5, a batch of airfoils is selected and analyzed to evaluate the aerodynamic coefficients of the wing with each airfoil. This analysis ultimately leads to the optimum airfoil being selected. Finally, design of the fuselage and tail, internal components selection, and servo-mechanisms design are carried out prior to a stability analysis. All these proposed steps are needed to design efficient and functional tilt-rotor mAVs.

关键词： Aerodynamic analysis Sizing Tilt-rotor mAV VTOL Stability

Variations of properties across plate thickness for Al alloy 7010

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中国有色金属学会会刊：英文版 2005年第6期15卷 1258-1263页

作者： m.salazar-Guapuriche Y.Y.Zhao A.Pitman A.Greene materials Laboratory Airbus UK Broughton Chester CH4 0DR UKDepartment of Engineering The University of Liverpool Liverpool L69 3GH UK Department of Engineering The University of Liverpool Liverpool L69 3GH UK materials and Process Group Airbus UK Filton Bristol BS99 7AR UK

The variations of electrical conductivity and hardness across the thickness of an Al alloy 7010 plate under the temper condition T7651 were investigated. The electrical conductivity and hardness respond in a reciprocal manner. Cross-sectional slices of the plate subjected to re-solutionising/natural ageing and re-solutionising/artificial ageing show the similar tendencies in property changes as in the as-received raw material. This clearly suggests that the property inhomogeneity across the plate thickness is inherent of the manufacturing route. The differences in properties through the plate thickness are due to the changes in the concentrations of the strengthening alloying elements in the solid solution and the associated changes in microstructure; these are believed to be mainly due to the nature of plate solidification and prolonged high temperature during the rolling operation. The combination of electrical conductivity and hardness can be used as an integral quality property indicator for assessing inhomogeneity of thick products.

关键词：铝合金镀层厚度硬度导电性

Development of single-cell-level microfluidic tech no logy for long-term growth visualization of living cultures of mycobacterium smegmatis

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microsystems & Nanoengineering 2021年第3期7卷 63-72页

作者： Han Wang gloria m.Conover Song-I Han James C.Sacchettini Arum Han Department of Biomedical Engineering School of MedicineTsinghua University100084 BeijingChina Department of Biochemistry and Biophysics Texas A&M UniversityCollege StationTX 77843USA Department of Electrical and Computer Engineering Texas A&M UniversityCollege StationTX 77843USA Department of Biomedical Engineering Texas A&M UniversityCollege StationTX 77843USA Department of medical Education Health Sciences CenterTexas A&M UniversityBryanTX 77807USA

Analysis of growth and death kinetics at single-cell resolution is a key step in understanding the complexity of the nonreplicating growth phenotype of the bacterial pathogen mycobacterium ***,we developed a single-cell-resolution microfluidic mycobacterial culture device that allows time-lapse microscopy-based Iong-term phenotypic visualization of the live replication dynamics of *** technology was successfully applied to monitor the real-time growth dynamics of the fast-growing model strain mycobacterium smegmatis(***)while subjected to drug treatment regimens during continuous culture for 48 h inside the microfluidic device.A clear morphological change leading to significant swelling at the poles of the bacterial membrane was observed during drug *** addition,a small subpopulation of cells surviving treatment by frontline antibiotics was observed to recover and achieve robust replicative growth once regular culture media was provided,suggesting the possibility of identifying and isolating nonreplicative *** device is a simple,easy-to-use,and low-cost solution for studying the single-cell phenotype and growth dynamics of mycobacteria,especially during drug treatment.

关键词： fluid culture treatment mycobacterium

Violence at work and its relationship with burnout, depression and anxiety in healthcare professionals of the emergency services

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Health 2013年第2期5卷 193-199页

作者： gloria m. Roldán Isabel C. salazar Laura Garrido Juan m. Ramos “La Caleta” Healthcare Center Granada Spain “Virgen de las Nieves” University Hospital Granada Spain University of Granada Granada Spain

The aim of this study was to examine the possible relationship between physical and psychological aggression suffered in the workplace and professional burnout, depression and anxiety suffered by healthcare professionals of the emergency services. methods: 315 physicians, nurses, orderlies and ambulance drivers of Critical Care and Emergency Devices (CCED) in the Andalusian Public Health System, in the province of Granada (Spain) participated. They were interviewed about the exposure to violence at work and answered a battery of questions that measured burnout, depression and anxiety. Results: Physical aggression was significantly related to emotional exhaustion, personal accomplishment at work, depression and anxiety. Psychological aggression was associated with personal accomplishment. Logistic regression showed that the CCED professionals who have suffered physical aggression were 4.2 and 2.6 times more likely to have suffered anxiety and reduced personal accomplishment, respectively, than those who did not suffer physical aggression. On the other hand, feelings of anxiety and reduced personal accomplishment increase the professionals’ risk (3.4 and 2.1 times more likely, respectively) of suffering from physical aggression. Conclusion: The results suggest that exposure to violence is related to the other psychological problems tested: emotional exhaustion and personal accomplishment (two components of burnout), depression and anxiety. In addition, physical violence is a risk factor for anxiety and diminished personal accomplishment of the CCED professionals.

关键词： Workplace Violence Aggression Burnout Depression Anxiety Health Professionals Emergency Services

Long-distance nitrate signaling displays cytokinin dependent and independent branches

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Journal of Integrative Plant Biology 2016年第3期58卷 226-229页

作者： Sandrine Ruffel Arthur Poitout Gabriel Krouk gloria m.Coruzzi Benoit Lacombe Biochemistry and Plant molecular Physiology Integrative Biology Institute for Plants'Claude Grignon'UmR CNRS/INRA/SupAgro/Um Place Pierre Viala 34060 Montpellier cedexFrance Center for Genomics and Systems Biology Department of Biology New York University New YorkNY 10003USA

The long-distance signaling network allowing a plant to properly develop its root system is crucial to optimize root foraging in areas where nutrients are available. Cytokinin is an essential element of the systemic signaling network leading to the enhancement of lateral root proliferation in areas where nitrate is available. Here,we explore more precisely：（i） which particular traits of lateral root growth（density and length of emerged lateral roots） are the targets of systemic signaling in a context of heterogeneous nitrate supply; and（ii） if the systemic signaling depends only on cytokinin or on a combination of several signalings.

关键词： Cytokinin development nitrate root systemic

A pilot study of the modulation of sirtuins on arylamine N-acetyltransferase 1 and 2 enzymatic activity

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Acta Pharmaceutica Sinica B 2018年第2期8卷 188-199页

作者： Eneida Turiján-Espinoza Rául Alejandro salazar-González Edith Elena Uresti-Rivera gloria Estela Hernández-Hernández montserrat Ortega-Juárez Rosa milán Diana Portales-Pérez Laboratory of Immunology and Cellular and molecular Biology Faculty of Chemical Science UASLP Laboratory of Biopharmacy and Pharmacokinetics Faculty of Chemical Science UASLP

Arylamine N-acetyltransferase(NAT; E.C. 2.***.1.5) enzymes are responsible for the biotransformation of several arylamine and hydrazine drugs by acetylation. In this process, the acetyl group transferred to the acceptor substrate produces NAT deacetylation and, in consequence, it is susceptible of degradation. Sirtuins are protein deacetylases, dependent on nicotine adenine dinucleotide,which perform post-translational modifications on cytosolic proteins. To explore possible sirtuin participation in the enzymatic activity of arylamine NATs, the expression levels of NAT1, NAT2,SIRT1 and SIRT6 in peripheral blood mononuclear cells(PBmC) from healthy subjects were examined by flow cytometry and Western blot. The in situ activity of the sirtuins on NAT enzymatic activity was analyzed by HPLC, in the presence or absence of an agonist(resveratrol) and inhibitor(nicotinamide) of sirtuins. We detected a higher percentage of positive cells for NAT2 in comparison with NAT1, and higher numbers of SIRT1t cells compared to SIRT6 in lymphocytes. In situ NAT2 activity in the presence of NAm inhibitors was higher than in the presence of its substrate, but not in the presence ofresveratrol. In contrast, the activity of NAT1 was not affected by sirtuins. These results showed that NAT2 activity might be modified by sirtuins.

关键词： Arylamine N-acetyltransferase NAT Sirtuins Peripheral blood mononuclear cells Nicotinamide Resveratrol

Genetic Analyses of Tolerance to Low Nitrogen in Tropical maize Germplasm

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Agricultural Sciences in China 2002年第9期1卷 954-959页

作者： Carpena A.L. salazar A.m. Department of Agronomy University of the Philippines Los BanosPhilippinesInstitute of Plant BreedingUPLBphilippines

Six tropical maize inbred lines were crossed in a half diallel fashion and evaluated along with their F1 hybrids under low N (0 kg/ha) and high N(170 kg/ha), for grain yield, ear diameter, ear length, number of rows per ear, 100-kernel weight, ear leaf area, shoot dry weight, ear leaf chlorophyll content and plant height to determine their response to different level of N. Grain yield and ear leaf chlorophyll content measured by 48% lower under -N than under + N, and were most affected by -N. Ear length had the highest reduction under -N of 22%. Plant height and shoot dry weight were both reduced by 28%. Diallel analysis indicated significant additive as well as dominance variance for grain yield under -N. The same results were shown when one tolerant x nontolerant cross from the diallel hybrids was subjected to generation mean analysis which also indicated significant epistatic effects. These results suggest that S1 or S2 progeny selection may be an effective means of improving grain yield of tropical maize under low soil N.

关键词： maize breeding maize Tolerance to low N Genetic analysis

Three-dimensional organ modeling based on deformable surfaces applied to radio-oncology

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第6期11卷 407-417页

作者： gloria BUENO Oscar DéNIZ Jesús SALIDO Carmen CARRASCOSA José m. DELGADO Grupo de Visióny Sistemas Inteligentes Universidad de Castilla-La Mancha E.T.S. Ingenieros Industriales Avda. Camilo José Cela 3. 13071 Ciudad Real Spain Hospital General de Ciudad Real Tomelloso s/n. 13005 Ciudad Real Spain Instituto Oncológico (Grupo ImO) modesto Lafuente 14 28010 Madrid Spain

This paper describes a method based on an energy minimizing deformable model applied to the 3D biomechanical modeling of a set of organs considered as regions of interest (ROI) for radiotherapy. The initial model consists of a quadratic surface that is deformed to the exact contour of the ROI by means of the physical properties of a mass-spring system. The exact contour of each ROI is first obtained using a geodesic active contour model. The ROI is then parameterized by the vibration modes resulting from the deformation process. Once each structure has been defined, the method provides a 3D global model including the whole set of ROIs. This model allows one to describe statistically the most significant variations among its structures. Statistical ROI variations among a set of patients or through time can be analyzed. Experimental results are presented using the pelvic zone to simulate anatomical variations among structures and its application in radiotherapy treatment planning.

关键词： 3D biomechanical organ modeling Energy minimizing deformable model Finite element model Geodesic active contour Radiotherapy treatment planning

Adaptive Control for Passive Kinesiotherapy ELLTIO

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Journal of Bionic Engineering 2014年第4期11卷 581-588页

作者： Ricardo López Hipólito Aguilar Sergio salazar Rogelio Lozano Laboratory UmI LAFmIA 3175 CINVESTAV-CNRS Móxico D. F. CNRS Research Director Universitb de Technologie de Compiègne 60200 Compiègne France

Exoskeletons are mechatronic devices used to increase human muscle strength and resistance. In the last decade these devices have become a very useful tool to assist active kinesiotherapy. This paper presents the design of exoskeleton focused on the rehabilitation of ankle and knee for the right leg. The construction of prototype like Exoskeleton for Lower Limb Training with Instrumented Orthoses （ELLTIO） using Series Elastic Actuator （SEA） to reduce the effort in the human joints, and a control law to perform a rehabilitation routine using an adaptive control scheme were first implemented in simulation to verify the control strategy and make a real rehabilitation test. The adaptive control law is proposed with the intention that the exoskeleton can adapt to user parameters at the time when performing the exercise. The results show the parameters estimation and tracking trajectory for the exoskeleton were proposed, and this trajectory could be a routine rehabilitation proposed by the therapist.

关键词： exoskeleton parametric identification rehabilitation robotics adaptive control.