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MXene multi-functionalization of polyrotaxane based PCMs and the applications in electronic devices thermal management

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Nano Materials Science 2024年第5期6卷 495-503页

作者： Guangzhong Yin Alba Marta Lopez Ignacio Collado antonio Vazquez-Lopez Xiang Ao jose Hobson Silvia G.Prolongo Deyi Wang Escuela Politecnica Superior Universidad Francisco de VitoriaCtra.Pozuelo-Majadahonda Km 1.80028223 Pozuelo de AlarconMadridSpain IMDEA Materials Institute C/Eric Kandel228906GetafeMadridSpain Materials Science and Engineering Area Escuela Superior de Ciencias Experimentales y TecnologíaUniversidad Rey Juan CarlosC/Tulipan s/n28933MadridSpain Universidad Carlos III de Madrid Departamento de Ciencia e Ingeniería de Materiales e Ingeniería QuímicaIAAB.Avda.Universidad3028911LeganesMadridSpain Instituto de Tecnologías para la Sostenibilidad Universidad Rey Juan CarlosC/Tulipan s/n28933MadridSpain

The aim of this work was to improve the thermal conductivity and electromagnetic shielding of the leakage proof phase change materials(PCMs),in which a polyrotaxane(PLR)was used as a support material to encapsulate PEG 1k or PEG 6k and MXene as multi-functional *** PCMs can be processed conveniently by a hot press and the PEG 1k containing samples showed excellent *** conducted a systematic evaluation of the phase transition behavior of the material,thermal conductivity and electromagnetic shielding performance ***,the PCMs achieved a high enthalpy values(123.9–159.6 J/g).The PCMs exhibited an increase of 44.3%,and 137.5%in thermal conductivity values with higher MXene content(5 wt%)for PLR-PEG6k and PLR-PEG1k,respectively,and show high shape stability and no leakage during and after phase *** introduction of MXene can significantly improve the electromagnetic shielding performance of PCM ***,higher conductive samples(samples which contain high MXene contents)offer a higher EMI SE shielding,reaching a maximum of 4.67 dB at 5.6 GHz for *** improvements solve the main problems of organic PEG based PCMs,thus making PLR-PEG-MXene based PCMs good candidates for thermoregulators of both solid-state disks and smart *** is worth pointing out that the sample PLR-1k-MX5 can decrease 4.3C of the reference temperature during cellphone ***,the temperature of the protecting sheet in the simulated solid state disk with PCM was significantly lower(showing a decreasing of 7.9℃)compared with the blank sample.

关键词： Phase change materials Thermal regulation MXene Polyrotaxane Nanocomposites

Analysing vaccine efficacy evaluated in phase 3 clinical trials carried out during outbreaks

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Infectious Disease Modelling 2024年第4期9卷 1027-1044页

作者： Francisco antonio Bezerra Coutinho Marcos Amaku Fernanda Castro Boulos jose Alfredo de Sousa Moreira Joao Italo DiasFranca Julio antonio do Amaral Eliana Nogueira Castro de Barros Claudio jose Struchiner Esper Jorge Kallas Eduardo Massad School of Medicine University of Sao PauloBrazil Instituto Butantan Sao PauloBrazil School of Applied Mathematics Fundacao Getulio VargasRio de JaneiroBrazil

In this paper we examine several definitions of vaccine efficacy(VE)that we found in the literature,for diseases that express themselves in outbreaks,that is,when the force of infection grows in time,reaches a maximum and then *** fact that the disease occurs in outbreaks results in several problems that we *** propose a mathematical model that allows the calculation of VE for several *** trials usually needs a large number of volunteers that must be ***,all volunteers should be enrolled in approximately the same time,but this is generally impossible for logistic reasons and they are enrolled in a fashion that can be replaced by a continuous density function(for example,a Gaussian function).The outbreak can also be replaced by a continuous density function,and the use of these density functions simplifies the ***,for example Gaussian functions,one of the problems one can immediately notice is that the peak of the two curves do not occur at the same *** model allows us to conclude:First,the calculated vaccine efficacy decreases when the force of infection increases;Second,the calculated vaccine efficacy decreases when the gap between the peak in the force of infection and the peak in the enrollment rate increases;Third,different trial protocols can be simulated with this model;different vaccine efficacy definitions can be calculated and in our simulations,all result are approximately the *** final,and perhaps most important conclusion of our model,is that vaccine efficacy calculated during outbreaks must be carefully examined and the best way we can suggest to overcome this problem is to stratify the enrolled volunteer's in a cohort-by-cohort basis and do the survival analysis for each cohort,or apply the Cox proportional hazards model for each cohort.

关键词： Vaccine efficacy Clinical trials Mathematical models Simulations Covid-19

Managing liver transplantation during the COVID-19 pandemic:A survey among transplant centers in the Southeast United States

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World Journal of Hepatology 2021年第12期13卷 2161-2167页

作者： Adalberto jose Gonzalez Nikhil Kapila Emmanuel Thomas antonio Pinna Andreas Tzakis Xaralambos Bobby Zervos Department of Gastroenterology Cleveland Clinic FloridaWestonFL 33324United States Department of Transplant Cleveland Clinic FloridaWestonFL 33331United States Schiff Center for Liver Diseases University of Miami Miller School of MedicineMiamiFL 33136United States

BACKGROUND The coronavirus disease-2019(COVID-19)pandemic has had a profound worldwide ***,it has led to a vast decrease in organ transplantation,including liver transplants(LT).There is little data regarding adjustments made by LT centers as a response to the COVID-19 *** To assess the experience of LT centers in the United States during the *** We performed an observational survey study from May 11,2020 to June 5,*** sent out a 13 question survey to 15 LT centers across the southeastern United *** Eleven LT centers responded to the *** found that(11/11)100%of transplant centers made adjustments because of the COVID-19 *** least 50%of transplant centers had at least one transplant recipient infected with *** adjust,greater than 50%of centers performed fewer LT,100%of patients were tested for COVID-19,and most centers implemented a virtual *** The COVID-19 pandemic greatly affected liver transplantation in the southeastern United *** was evident that a concerted effort was made by LT centers to protect their patients and employees from COVID-19 but also to continue the lifesaving procedure of LT in this sick patient *** studies are needed to assess how LT centers around the world managed the pandemic in order to learn strategies to continue life-saving procedures in this patient population.

关键词： COVID-19 Liver transplantation Survey Telemedicine Immunosuppression Solid organ transplantation

Influence of peanut skin extract on shelf-life of sheep patties

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Asian Pacific Journal of Tropical Biomedicine 2016年第7期6卷 586-596页

作者： Paulo Eduardo Sichetti Munekata Rafaella de Paula Paseto Fernandes Mariza Pires de Melo Marco antonio Trindade jose Manuel Lorenzo Department of Food Engineering Faculty of Animal Science and Food EngineeringUniversity of Sao Paulo Department of Basic Sciences Faculty of Animal Science and Food Engineering University of Sao Paulo Department of Basic Sciences Faculty of Animal Science and Food EngineeringUniversity of Sao Paulo Meat Technologicial Center of Galicia

Objective: To evaluate the phenolic profile and antioxidant activity in vitro of peanut skin extract(PSE) and effect of PSE on characteristics of sheep patties during ***: PSE phenolic profile was evaluated in LC–MS analysis and by total phenolic content, 1,1-diphenyl-2-picrylhydrazyl radical scavenging capacity and ferric reducing/antioxidant power. Patties elaborated with sheep meat were packaged in modified atmosphere and storage at(2 ± 1)C. The analyses were performed every 5 days for 20 days on microbial counts, physico-chemical properties, lipid oxidation, protein stability and sensory ***: The major group of phenolic compounds in PSE was the proanthocyanidins followed by other flavonoids, which are related to potential phenolic content and antioxidant activity. The addition of PSE and butyl hydroxytoluene(BHT) reduced the microbial counts during the storage time, caused reduction on the loss of redness and sensory properties over time. The lipid and protein oxidation in sheep patties was effectively inhibited by PSE and ***: The present results showed the potential application of PSE as a natural alternative to replace synthetic antioxidants(BHT) for increasing the quality and extending the shelf-life of sheep patties.

关键词： Peanut skin extract henolic profile Lipid and protein oxidation Microbial counts

Objective assessment of the effect of pupil size upon the power distribution of multifocal contact lenses

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International Journal of Ophthalmology(English edition) 2017年第1期10卷 103-108页

作者： Eleni Papadatou antonio J.Del Aguila-Carrasco jose J.Esteve-Taboada David Madrid-Costa Alejandro Cervino-Exposito Optometry Research Group University of ValenciaValencia 46100Spain Optics Ⅱ Department Optics and Optometry FacultyComplutense University of MadridMadrid 28037Spain

AIM： To analytically assess the effect of pupil size upon the refractive power distributions of different designs of multifocal contact ***： Two multifocal contact lenses of center-near design and one multifocal contact lens of center-distance design were used in this study. Their power profiles were measured using the NIMO TR1504 device （LAMBDA-X, Belgium）. Based on their power profiles, the power distribution was assessed as a function of pupil size. For the high addition lenses, the resulting refractive power as a function of viewing distance （far, intermediate, and near） and pupil size was also ***： The power distribution of the lenses was affected by pupil size differently. One of the lenses showed a significant spread in refractive power distribution, from about ？3 D to 0 D. Generally, the power distribution of the lenses expanded as the pupil diameter became greater. The surface of the lens dedicated for each distance varied substantially with the design of the ***： In an experimental basis, our results show how the lenses power distribution is affected by the pupil size and underlined the necessity of careful evaluation of the patient’s visual needs and the optical properties of a multifocal contact lens for achieving the optimal visual outcome.

关键词： multifocal contact lenses pupil size power profiles refractive power distribution

Ethical and Legal Arguments about Telemedicine in Colombia

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Journal of Computer and Communications 2017年第3期5卷 116-128页

作者： jose antonio García Pereánez American University Corporation MedellinColombia University of Antioquia MedellinColombia

This paper makes a reflection of humanistic approach about telemedicine in the cyber culture context, including a debate on the “digital era” and the nature of human communication. It is aimed at interpreting the influence of the technological era in the communication between the emitting subjects and receptors that emerge from communicative relations in telemedicine. This is the result of the analysis on legitimacy and legality of Communication for Health among individuals interacting in the cyberspace, mediated and conceived by modern technologies such as computer science, telematics and cybernetics. Telemedicine, according to ethical and legal proposals, can be subject of criticism because of the displacement of the medical doctor-patient relationship. Bigger distance and asymmetries in the medical act are established, being exposed to the inter-subjective relations of the cyberspace that immerses the patient into a deeper vulnerability, mediated by the technology that overflows him. A literature review through the empirical-analytical method, aimed at describing the impact of telemedicine in users, was done. This technology of recent use in Colombia promises to become a tool to support the solution of some health problems. Its development must be linked to the use of regulations that involve the “must be”, and its application must be decided according to legal principles that take on responsibility on medical doctors and technicians. The inevitable development of medical technology and its application in telemedicine may lead to the vulnerability of ethical principles, and consequently, the harm and misinterpretation of the medical act.

关键词： Medical Act Ethical-Legal Cyberculture Digital Subject Telemedicine

A model of bone adaptation as a topology optimization process with contact

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Journal of Biomedical Science and Engineering 2012年第5期5卷 229-244页

作者： antonio Andrade-Campos antonio Ramos jose A.Simoes Department of Mechanical Engineering Centre for Mechanical Technology&AutomationUniversity of AveiroCampus Universitário de SantiagoAveiroPortugal

Topology optimization is presently used in most diverse scientific, technologic and industrial areas, including biomechanics. Bone remodelling models and structural optimization has mutually provided inspiration for new developments in biomechanics and biomedicine. Considering that bone has the ability to adapt its internal structure to mechanical loading (Wolff’s law and Roux’s paradigm), it is possible to model the behaviour of the bone structure by the use of a topology optimization methodology whose optimization variables can be the relative densities and the orthotropic directions. In this work, the internal bone adaptation of a proximal femur is considered. The bone-remodelling scheme is numerically described by a time-dependent evolutionary procedure with anisotropic material parameters. The remodelling rate equation is obtained from the structural optimization task of maximizing the stiffness subject to a biological cost associated with metabolic maintenance of bone tissue in time. The situation of multiple load conditions is considered for a three-dimensional finite element model of the proximal femur. The bone density distribution of a real femur is used as the initial design for the onset of the remodelling mechanism. Examples of bone adaptation resulting from load changes are presented. The three-dimensional finite element model of the proximal femur with initial bone density distribution was adapted to implant a cementless stem. A remeshing technique is used to assign the bone relative density distribution to the new geometry and mesh. The time adaptation of the bone is assessed considering contact with friction at the bone-stem interface. Results of bone density evolution and osteointegration distribution are obtained.

关键词： Bone remodelling Topology Optimization Finite element Contact Osteointegration

Tropical tree community composition and diversity variation along a volcanic elevation gradient

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Journal of Mountain Science 2022年第12期19卷 3475-3486页

作者： Ruben MARTINEZ-CAMILO Manuel MARTINEZ-MELENDEZ Nayely MARTINEZ-MIELENDEZ Derio antonio JIMENEZ-LOPEZ Mauricio jose-RIOS Unidad Villa Corzo Facultad de IngenieríaUniversidad de Ciencias y Artes de Chiapas30520 Villa CorzoChiapasMexico Instituto de Ciencias Biológicas Universidad de Ciencias y Artes de Chiapas29039 Tuxtla GutiérrezChiapasMexico Eizia A.C. 29045 Tuxtla GutiérrezChiapasMexico Departamento de Conservación de la Biodiversidad El Colegio de la Frontera Sur29290 San Cristóbal de las CasasChiapasMexico Orquidiario y Jardín Botánico de Comitán Secretaría de Medio Ambiente e Historia Natural30106 Comitán de DomínguezChiapasMexico Instituto de Investigación en Gestión de Riesgos y Cambio Climático Universidad de Ciencias y Artes de Chiapas29039 Tuxtla GutiérrezChiapasMexico

Unraveling the factors that determine variation of diversity in tropical mountain systems is a topic for debate in plant *** is especially true in areas where topography is complex due to volcano elevational gradients and where forests are vulnerable to human *** this study we used a set of climatic(temperature,rainfall,and radiation solar),topographic(elevation,slope aspect,and slope orientation)and human disturbance variables to determine their effect on diversity and composition patterns of a tree community,considering three slope aspects of a tropical volcano in southeastern *** sampled trees in seventy 0.1-ha plots distributed on three slope aspects of the Tacanávolcano along an elevational gradient of 1500 to 2500 *** determined diversity patterns(general tree richness,exponential of Shannon index,and pioneer species richness)with linear regression models,and for beta diversity,we used a dissimilarity index(within and between elevational bands 100 m wide).The effect of a set of environmental and human disturbance variables on tree diversity and community composition was analyzed with general linear models and multivariate analyses,*** registered 2,949 individual trees belonging to 176 species and *** average species richness and alpha diversity per plot were 13(standard deviation±6)and 9(±5),*** tree richness and alpha diversity increased in the middle part(unimodal patterns)of the elevational gradient,but pioneer species richness decreased linearly with *** variance explained by general linear models was greater in richness(32%)than in alpha diversity(25.3%).The most important predictor variables were temperature(elevational gradient),which explained the unimodal pattern(richness and alpha diversity increase at intermediate levels of temperature),and slope orientation,which explained the increase in richness and alpha diversity toward the geographic *** temperature had a signific

关键词： Composition Environmental gradient Tree diversity patterns Tropical humid cloud forest Tropical volcanoes

Fiber Optic Intensity-Modulated Sensors： a Review in Biomechanics

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Photonic Sensors 2012年第4期2卷 315-330页

作者： Paulo RORIZ antonio RAMOS jose L. SANTOS jose A. SIMOES Department of Mechanics University of Aveiro 3810-193 Aveiro Portugal Faculty of Sciences University of Porto Rua do Campo Alegre 687 4150-179 Porto Portugal

Fiber optic sensors have a set of properties that make them very attractive in biomechanics. However, they remain unknown to many who work in the field. Some possible causes are scarce information, few research groups using them in a routine basis, and even fewer companies offering turnkey and affordable solutions. Nevertheless, as optical fibers revolutionize the way of carrying data in telecommunications, a similar trend is detectable in the world of sensing. The present review aims to describe the most relevant contributions of fiber sensing in biomechanics since their introduction, from 1960s to the present, focusing on intensity-based configurations. An effort has been made to identify key researchers, research and development （R＆D） groups and main applications.

关键词： Biomechanics fiber optic sensors intensity-modulated sensors