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Estrogen rapid effects:a window of opportunity for the aging brain?

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Neural Regeneration Research 2022年第8期17卷 1629-1632页

作者： Ivanny marchant Jana Stojanova Lilian Acevedo Pablo Olivero Laboratorio de Modelamiento en Medicina Escuela de MedicinaUniversidad de ValparaísoViña del MarChile Interdisciplinary Centre for Health Studies(CIESAL) Universidad de ValparaísoViña del MarChile Servicio de Neurología Hospital Carlos van Buren ValparaísoChile Laboratorio de Estructura y Función Celular Escuela de MedicinaFacultad de MedicinaUniversidad de ValparaísoValparaísoChile Centro Interoperativo en Ciencias Odontológicas y Médicas Universidad de ValparaísoValparaísoChile

Estrogen produces several beneficial effects in healthy neurological tissues and exhibits cardioprotective effects.Hormone therapy has been widely used to treat menopausal estrogen deficiency for more than 80 years.Despite high initial expectations of cardioprotective effects,there has been substantial distrust following important randomized clinical trials,such as the Women’s Health Initiative.Subsequently,the timing of treatment in relation to the onset of menopause came under consideration and led to the proposal of the timing hypothesis,that early initial treatment is important,and benefits are lost as the timing since menopause becomes prolonged.Subsequent analyses of the Women’s Health Initiative data,together with more recent data from randomized and observational trials,consistently show reductions in coronary heart disease and mortality in younger menopausal women.Regarding cognitive function,the timing hypothesis is consistent with observations from basic and animal studies.There is some clinical evidence to support the benefits of hormonal therapy in this context,though skepticism remains due to the paucity of clinical trials of substantial length in younger menopausal women.It is likely that the effects of estrogens on cognitive performance are due to rapid mechanisms,including mechanisms that influence Ca2+homeostasis dynamics,provide protection in a hostile environment and reduce inflammatory signals from neural tissues.In the future,inflammatory profiles accounting for early signs of pathological inflammation might help identify the‘window of opportunity’to use estrogen therapy for successful cognitive protection.

关键词： aging cardiovascular prevention cognitive function estrogen hormone treatment inflammaging rapid effects timing hypothesis TRPV1 window of opportunity

Exploring the configuration space of elemental carbon with empirical and machine learned interatomic potentials

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npj Computational Materials 2023年第1期9卷 987-998页

作者： George A.marchant Miguel A.Caro Bora Karasulu Livia B.Pártay Department of Chemistry University of WarwickCoventry CV47ALUK Department of Chemistry and Materials Science Aalto University02150 EspooFinland

We demonstrate how the many-body potential energy landscape of carbon can be explored with the nested sampling algorithm,allowing for the calculation of its pressure-temperature phase diagram.We compare four interatomic potential models:Tersoff,EDIP,GAP-20 and its recently updated version,GAP-20U.Our evaluation is focused on their macroscopic properties,melting transitions,and identifying thermodynamically stable solid structures up to at least 100 GPa.The phase diagrams of the GAP models show good agreement with experimental results.However,we find that the models’description of graphite includes thermodynamically stable phases with incorrect layer spacing.By adding a suitable selection of structures to the database and re-training the potential,we have derived an improved model—GAP-20U+gr—that suppresses erroneous local minima in the graphitic energy landscape.At extreme high pressure nested sampling identifies two novel stable structures in the GAP-20 model,however,the stability of these is not confirmed by electronic structure calculations,highlighting routes to further extend the applicability of the GAP models.

关键词： carbon potential configuration

Intention and automaticity toward physical and sedentary screen-based leisure activities in adolescents:A profile perspective

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Journal of Sport and Health Science 2018年第4期7卷 481-488页

作者： gonzalo marchant guillaume chevance julie boiché laboratory epsylon"dynamics of human abilities and health behavior"(ea 4556) university of montpellier4 boulevard henriⅳMontpellier 34000France laboratory l-vis(ea 7428) university claude bernard lyon 1Batiment R.Dubois-27-29 bd du 11 novembre 1918Villeurbanne cedex 69622.France clinique du souffle la vallonie 5 sante group800avenue joseph vallotLodeve 34700France

Purpose: Physical activity(PA) and sedentary behavior(SB) are increasingly considered independent health behaviors. Additionally, current research suggests that both controlled and automatic determinants account for their adoption. The purpose of this article was to identify intentionàautomaticity profiles toward PA and screen-based SB and to examine how those profiles are associated with different behavioral patterns.Method: Two cross-sectional studies based on self-report questionnaires were conducted with French high school students(Study 1: n = 198;Study 2: n = 185).Results: In all, 4 distinct motivational profiles appeared. The first 3 clusters emerged in both studies: "PA"(high levels of automaticity and intention for PA, low levels of automaticity and intention for screen-based SB); "screen"(high levels of automaticity and intention for screen-based SB, low levels of automaticity and intention for PA), and "mixed"(high levels of all variables), whereas the fourth cluster was observed only in Study 2: "high control"(below-mean levels of automaticity, high levels of intention toward both PA and screen-based SB). Adolescents with a screen profile displayed the least healthy behavioral pattern, whereas those in the PA profile demonstrated the most favorable behaviors.Conclusion: Future research is needed to extend these results to other populations using complementary assessment methods of automatic psychological processes and PA and SB behaviors.

关键词：青少年屏幕侧面物理上海大学心理过程评价方法 PA

Do PI3-kinase mutations drive T cells insane？

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Cellular & Molecular Immunology 2014年第4期11卷 320-322页

作者： David Vermijlen Michel Y Braun Arnaud marchant Institute of Pharmacy Universite Libre de Bruxelles (ULB) Belgium Institute for Medical Immunology Universite Libre de Bruxelles (ULB) Belgium

The link between the differentia- tion of effector T lymphocytes and metabolism has become an important area of research. The role played by the phosphoinositide 3-kinase （PI3K）/Akt/ mTOR （mammalian target ofrapamycin） pathway in this process was recently emphasized by Lucas et al.1 who reported a series of primary immunodeficiency patients with three different germ-line, gain-of-function mutations of the p1108 subunit of PI3K. The patients consistently presented a deficiency in naive T lymphocytes and an accumulation of highly differentiated effector T cells. This phenotype was associated with recurrent respiratory infections and with the reactivation of persistent viruses. The disease was named PASLI （p1108-activating mutation causing senescent T cells, lymphadenopathy and immunodeficiency）. The same disorder was simultaneously reported by Angulo et al.z and was named the activated PI3K-8 syndrome （APDS）. Although the accumulation of effector T cells in the state of immunodeficiency was somewhat unexpected, the description of this syn- drome provides important insight into the regulation of T-cell differentiation and T-cell memory.

关键词：磷酸肌醇3-激酶类 T淋巴细胞表型呼吸道感染记忆淋巴系统疾病内皮缩血管肽类内驱力

TRPV1 may increase the effectiveness of estrogen therapy on neuroprotection and neuroregeneration

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Neural Regeneration Research 2016年第8期11卷 1204-1207页

作者： Ricardo Ramírez-Barrantes Ivanny marchant Pablo Olivero Escuela de Medicina Universidad de Valparaíso

Aging induces physical deterioration,loss of the blood brain barrier,neuronal loss-induced mental and neurodegenerative diseases.Hypotalamus-hypophysis-gonad axis aging precedes symptoms of menopause or andropause and is a major determinant of sensory and cognitive integrated function.Sexual steroids support important functions,exert pleiotropic effects in different sensory cells,promote regeneration,plasticity and health of the nervous system.Their diminution is associated with impaired cognitive and mental health and increased risk of neurodegenerative diseases.Then,restoring neuroendocrine axes during aging can be key to enhance brain health through neuroprotection and neuroregeneration,depending on the modulation of plasticity mechanisms.Estrogen-dependent transient receptor potential cation channel,subfamily V,member 1（TRPV1） expression induces neuroprotection,neurogenesis and regeneration on damaged tissues.Agonists of TRPV1 can modulate neuroprotection and repair of sensitive neurons,while modulators as other cognitive enhancers may improve the survival rate,differentiation and integration of neural stem cell progenitors in functional neural network.Menopause constitutes a relevant clinical model of steroidal production decline associated with progressive cognitive and mental impairment,which allows exploring the effects of hormone therapy in health outcomes such as dysfunction of CNS.Simulating the administration of hormone therapy to virtual menopausal individuals allows assessing its hypothetical impact and sensitivity to conditions that modify the effectiveness and efficiency.

关键词： TRPV1 estrogen hormonal replacent neuroprotection aging

The Role of Chilean Mountain Areas in Time of Drought and Energy Crisis:New Pressures and Challenges for Vulnerable Ecosystems

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Journal of Mountain Science 2012年第4期9卷 451-462页

作者： Rafael SáNCHEZ Carla marchant Axel BORSDORF Institute for Geography Pontifical University Catholic of ChileAvenida Vicu a Mackenna 4860MaculSantiago de Chile Institute for Geography University of InnsbruckInnrain 526020 InnsbruckAustria Institute for Mountain Research:Man and Environment Austrian Academy of SciencesTechnikerstr.21a6020 InnsbruckAustria

In the summer of 2010/2011 Chile suffered the third most severe energy and water supply crisis in only one decade.This may be surprising as the Andes which accompany the country along 4,200 km are a water tower and could provide more electricity and water than needed.On top of that,it has to be mentioned that Chile also counts with sunny and windy climates and with excellent geothermal energy resources and thus has a huge potential as far as renewable energies are concerned.After analyzing the existing natural conditions,the infrastructure and the present challenges of climate change,it has to be asked in which way Chile can make use of this potential in the near future,considering the legal and political situation and the technological opportunities.It seems that the resources are still hidden in the Andes,and only the key is missing to realize the country's natural potential.This research has been based on the analysis of existing literature,media,quantitative data from government institutions and other antecedents obtained by the authors in field work done in the South of Chile in 2010.The added value of this compilation lies in the comprehensive perspective,linking the knowledge of climatologists,hydrologists,mountain researchers and energy experts in order to support a sustainable energy and water supply for the future in Chile.From this present research,it can be concluded that Chile necessarilyhas to adopt new energy-related strategies,particularly those aimed at diminishing the strong dependence on traditional sources of energy and establishing new techniques and technologies for generating electricity and utilizing the vast potential that the country is ready to offer,such as that provided by the Andes along 4,200 kilometers.

关键词：能源危机智利生态系统安第斯山脉压力干旱山区气候变化

DSC STUDY ON THE WATER-ABSORBING MECHANISM OF PLASMA POLYMERIZED N-VINYL-2-PYROROLIDONE

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Chinese Chemical Letters 1991年第11期2卷 889-892页

作者： Ding Sheng YU R.E.marchant Department of Applied Chemistry Beijing Institute of Chemical TechnologyBeijing100029 Department of Macromolecular Science Case Western Reserve UniversityU.S.A.

Water existing in water-absorbing plasma polymerized N-vinyl-2-pyrrolidone(PPNVP) include pure bulk water, freezable water and non-freezing, or bound, water. The C-N bond of N, N-disubstituted amides in PPNVP was cons... 详细信息

关键词： DSC STUDY ON THE WATER-ABSORBING MECHANISM OF PLASMA POLYMERIZED N-VINYL-2-PYROROLIDONE 加加 ESCA NVP

Modern Lifestyles Are Bad for Fertility Stress,dieting and exercise can dent women's reproductive capacity

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当代外语研究 2006年第8期 2-4页

作者： Jo marchant 何珊

压力、节食和健身可能引起女性不孕。不过,最近科学家们又发现,处于压力之下的女性,如果还进行节食及健身,不孕的机率可能会更高。这项发现是通过用猴子做实验而得出的。研究发现,经常改变母猴的生活环境,加上饮食欠佳,运动过度,母猴也... 详细信息

压力、节食和健身可能引起女性不孕。不过,最近科学家们又发现,处于压力之下的女性,如果还进行节食及健身,不孕的机率可能会更高。这项发现是通过用猴子做实验而得出的。研究发现,经常改变母猴的生活环境,加上饮食欠佳,运动过度,母猴也会出现无月经症。然而,另一项持续一年的对女性尿液的跟踪调查研究则发现,压力对女性的受孕影响并不是太大。下面就来看看科学家们到底是如何得出这些结论的。

关键词：科学家女性不孕压力无月经健身节食发现跟踪调查研究运动过度生活环境

Chinese Agricultural Products Entering the U.S. Markets After the WTO Accession

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China & World Economy 2004年第4期 66-78页

作者： Michael Reed Mary A. marchant U.S University of Kentucky Department of Agricultural Economics

Agricultural trade between the U.S. and China is very important for both countries. Focusingon the potential of Chinas agricultural products entering the U.S. markets, this researchintroduced the development of agricultural trade between the U.S. and China and analyzedthe impacts of the U.S.-China bilateral trade agreement and Chinas WTO membership onagricultural trade between the two countries. The authors also examined current and potentialcompetitiveness of Chinas agricultural products and provided suggestions to increaseChinas agricultural exports to the United States.

关键词： WTO FAS USDA In Markets After the WTO Accession Chinese Agricultural Products Entering the U.S than