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Journal of Energy Chemistry 2021年第2期30卷 241-250,I0009页

作者： Kun Zhao Marco Calizzi Emanuele Moioli Mo Li alexandre Borsay Loris Lombardo Robin Mutschler Wen Luo Andreas Zuttel Laboratory of Materials for Renewable Energy Institute of Chemical Sciences and Engineeringtcole Polytechnique Federale de Lausanne(EPFL)1951 SionSwitzerland Swiss Federal Laboratories for Materials Science and Technology(EMPA) 8600 DiibendorfSwitzerland

The relation between catalytic reactivities and metal/metal oxide ratios, as well as the functions of the metal and the metal oxides were investigated in the CO_2 hydrogenation reaction over highly active Co_x(CoO)_(1–x)catalysts in operando. The catalytic reactivity of the samples in the CO_2 methanation improves with the increased Co O concentration. Strikingly, the sample with the highest concentration of CoO, i.e., Co_(0.2)(CoO)_(0.8), shows activity at temperatures lower than 200 °C where the other samples with less CoO are inactive. The origins of this improvement are the increased amount and moderate binding of adsorbed CO_2 on CoO sites. The derivative adsorption species are found to be intermediates of the CH4 formation. The metallic Co functions as the electronically catalytic site which provides electrons for the hydrogenation steps. As a result, an abundant amount of CoO combined with Co is the optimal composition of the catalyst for achieving the highest reactivity for CO_2 hydrogenation.

关键词： Cobalt and cobalt oxide Reactivity CO_(2)hydrogenation Active site Adsorption Activation energy

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粒子云扩散完全解析和时间平均模拟的比较

Acta Mechanica Sinica 2022年第8期38卷 29-40页

作者： Akim Lavrinenko alexandre Fabregat Jordi Pallares Departament d’Enginyeria Mecánica Universitat Rovira i VirgiliSpainAv.Països CatalansTarragona 2643007Spain

本文将现有文献中轻度咳嗽的直接数值模拟(DNS)结果与k-ϵ模型的可压缩非定常雷诺平均N-S(URANS)方程得到的结果进行了比较.两种情况均采用单向耦合假设,将分散相模拟为球形拉格朗日粒子.URANS模型能够再现轻粒子(粒径小于64µm)的上升趋... 详细信息

本文将现有文献中轻度咳嗽的直接数值模拟(DNS)结果与k-ϵ模型的可压缩非定常雷诺平均N-S(URANS)方程得到的结果进行了比较.两种情况均采用单向耦合假设,将分散相模拟为球形拉格朗日粒子.URANS模型能够再现轻粒子(粒径小于64µm)的上升趋势,这归因于咳嗽所产生浮力的阻力作用.通过分析DNS和URANS的模拟结果发现,在重力作用下,大于64µm的粒子倾向于描述抛物线轨迹.网格独立性分析允许随着流动的发展,确定网格分辨率的增加对粒子云统计数据的影响.结果表明,k-ϵ模型过度预测了直径小于64µm颗粒的水平位移而对于大于64µm颗粒的预测则相反.

关键词：粒子云网格独立性统计数据单向耦合网格分辨率轻粒子抛物线

National botanical gardens at the forefront of global plant conservation

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The Innovation 2023年第5期4卷 1-2页

作者： Hai Ren alexandre Antonelli South China Botanical garden of the Chinese Academy of Sciences Guangzhou 510650China South China National Botanical garden Guangzhou 510650China Royal Botanic gardens KewRichmondLondonTW93AE SurreyUK gothenburg global Biodiversity Center Department of Biological and Environmental SciencesUniversity of GothenburgBox 46140530 GoteborgSweden|

global changes in land use driven by demands on food,energy,and other resources in response to a rapidly increasing human population have collectively led to escalating environmental challenges,including biodiversity loss,global warming,environmental pollution,and ecosystem degradation.At present,biodiversity is seriously threatened at global,regional,and local scales,which,in turn,threatens our own survival.Biodiversity is a global asset of immense material and non-material value,providing us with food,medicine,building materials,fiber,and the ecological environment required for our well-being and health.

关键词： collective pollution seriously

Biomarkers for detecting colorectal cancer non-invasively: DNA,RNA or proteins?

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World Journal of gastrointestinal Oncology 2020年第2期12卷 124-148页

作者： alexandre Loktionov Diag Nodus Ltd Babraham Research Campus

Colorectal cancer(CRC)is a global problem affecting millions of people worldwide.This disease is unique because of its slow progress that makes it preventable and often curable.CRC symptoms usually emerge only at advanced stages of the disease,consequently its early detection can be achieved only through active population screening,which markedly reduces mortality due to this cancer.CRC screening tests that employ non-invasively detectable biomarkers are currently being actively developed and,in most cases,samples of either stool or blood are used.However,alternative biological substances that can be collected non-invasively(colorectal mucus,urine,saliva,exhaled air)have now emerged as new sources of diagnostic biomarkers.The main categories of currently explored CRC biomarkers are:(1)Proteins(comprising widely used haemoglobin);(2)DNA(including mutations and methylation markers);(3)RNA(in particular microRNAs);(4)Low molecular weight metabolites(comprising volatile organic compounds)detectable by metabolomic techniques;and(5)Shifts in gut microbiome composition.Numerous tests for early CRC detection employing such non-invasive biomarkers have been proposed and clinically studied.While some of these studies generated promising early results,very few of the proposed tests have been transformed into clinically validated diagnostic/screening techniques.Such DNA-based tests as Food and Drug Administration-approved multitarget stool test(marketed as Cologuard®)or blood test for methylated septin 9(marketed as Epi proColon®2.0 CE)show good diagnostic performance but remain too expensive and technically complex to become effective CRC screening tools.It can be concluded that,despite its deficiencies,the protein(haemoglobin)detection-based faecal immunochemical test(FIT)today presents the most cost-effective option for non-invasive CRC screening.The combination of non-invasive FIT and confirmatory invasive colonoscopy is the current strategy of choice for CRC screening.However,continuing intense research in the area prom

关键词： Colorectal cancer screening Biomarkers Non-invasive testing Stool Colorectal mucus Blood

Mapping Between Charge-Dyon and Position-Dependent Mass Systems

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Communications in Theoretical Physics 2019年第10期71卷 1261-1266页

作者： Anderson L.de Jesus alexandre g.M.Schmidt Departamento de Fisica de Volta Redonda Instituto de Ciencias Exatas—Universidade Federal Fluminense

The primary purpose of this work is to reproduce the scenario composed of a charge-dyon system utilizing position-dependent effective mass(PDM) background in the non-relativistic and in the relativistic regimes. In the nonrelativistic case we substitute the exact charge-dyon eigenfunction into PDM Schr?dinger equation, in the Zhu-Kroemer parametrization, and then solve it for the mass distribution considering M = M(r). Analogously, in the relativistic case we study the Klein-gordon equation for a position-dependent mass, and in this case, we are able to analytically solve the equation for M = M(r, θ).

关键词： position-dependent mass Schrodinger equation Klein-gordon equation dyon

Eosinophils in the gastrointestinal tract and their role in the pathogenesis of major colorectal disorders

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World Journal of gastroenterology 2019年第27期25卷 3503-3526页

作者： alexandre Loktionov DiagNodus Ltd Babraham Research Campus

Eosinophils are currently regarded as versatile mobile cells controlling and regulating multiple biological pathways and responses in health and disease.These cells store in their specific granules numerous biologically active substances(cytotoxic cationic proteins, cytokines, growth factors, chemokines,enzymes) ready for rapid release. The human gut is the main destination of eosinophils that are produced and matured in the bone marrow and then transferred to target tissues through the circulation. In health the most important functions of gut-residing eosinophils comprise their participation in the maintenance of the protective mucosal barrier and interactions with other immune cells in providing immunity to microbiota of the gut lumen. Eosinophils are closely involved in the development of inflammatory bowel disease(IBD),when their cytotoxic granule proteins cause damage to host tissues. However,their roles in Crohn’s disease and ulcerative colitis appear to follow different immune response patterns. Eosinophils in IBD are especially important in altering the structure and protective functions of the mucosal barrier and modulating massive neutrophil influx to the lamina propria followed by transepithelial migration to colorectal mucus. IBD-associated inflammatory process involving eosinophils then appears to expand to the mucus overlaying the internal gut surface. The author hypothesises that immune responses within colorectal mucus as well as ETosis exerted by both neutrophils and eosinophils on the both sides of the colonic epithelial barrier act as additional pathogenetic factors in IBD. Literature analysis also shows an association between elevated eosinophil levels and better colorectal cancer(CRC) prognosis, but mechanisms behind this effect remain to be elucidated. In conclusion, the author emphasises the importance of investigating colorectal mucus in IBD and CRC patients as a previously unexplored milieu of disease-related inflammatory responses.

关键词： Eosinophils Eosinophilopoiesis gut lamina propria Colorectal mucus Normal human small intestine Normal human colon Inflammatory bowel disease Crohn’s disease Ulcerative colitis Colorectal cancer

Hybrid High‑Order Methods for the Acoustic Wave Equation in the Time Domain

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Communications on Applied Mathematics and Computation 2022年第2期4卷 597-633页

作者： Erik Burman Omar Duran alexandre Ern Department of Mathematics University College LondonLondon WC1E 6BTUK CERMICS Ecole des Ponts77455 Marne la Vallée Cedex 2France INRIA Paris 75589 ParisFrance

We devise hybrid high-order(HHO)methods for the acoustic wave equation in the time domain.We frst consider the second-order formulation in time.Using the Newmark scheme for the temporal discretization,we show that the resulting HHO-Newmark scheme is energy-conservative,and this scheme is also amenable to static condensation at each time step.We then consider the formulation of the acoustic wave equation as a frst-order system together with singly-diagonally implicit and explicit Runge-Kutta(SDIRK and ERK)schemes.HHO-SDIRK schemes are amenable to static condensation at each time step.For HHO-ERK schemes,the use of the mixed-order formulation,where the polynomial degree of the cell unknowns is one order higher than that of the face unknowns,is key to beneft from the explicit structure of the scheme.Numerical results on test cases with analytical solutions show that the methods can deliver optimal convergence rates for smooth solutions of order O(hk+1)in the H1-norm and of order O(h^(k+2))in the L^(2)-norm.Moreover,test cases on wave propagation in heterogeneous media indicate the benefts of using high-order methods.

关键词： Hybrid high-order methods Wave equation Newmark scheme Runge-Kutta scheme

Attempted altruistic infanticide in a context of psychotic decompensation induced by stress linked to the COVID-19 pandemic:a case report

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Forensic Sciences Research 2021年第2期6卷 148-151页

作者： Camille Jantzi alexandre perrin University centre of Legal Medicine(cUrML) University of GenevaGenevaswitzerland

the mediatization of the CoVID-19 pandemic has created a lot of stress leading sometimes to mental health issues.We present a case of a thirty-year-old woman with no history of psychotic disease but some vulnerabilities and no criminal record,who attempted to kill her seven-year-old son during a brief delusional episode in the context of fear of the coronavirus.she was successfully treated by pharmacotherapy and psychotherapy.she was examined by forensic psychiatrists leading to the conclusion that her responsibility was highly diminished,and her reoffending risk was low.We add to the literature that the CoVID-19 pandemic has been such a stressor for mentally vulnerable people that it could lead to severe psychiatric decompensation and even criminal acts.

关键词： Forensic sciences forensic psychiatry CoVID-19 infanticide psychosis criminal responsibility forensic evaluation

Dynamical machine learning volumetric reconstruction of objects’ interiors from limited angular views

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Light(Science & Applications) 2021年第5期10卷 824-844页

作者： Iksung Kang alexandre goy george Barbastathis Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology77 Massachusetts AveCambridgeMAUSA Department of Mechanical Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA Singapore-MIT Alliance for Research and Technology(SMART)Centre 1 Create WaySingapore 117543Singapore Omnisens SA Morges 1110Switzerland

Limited-angle tomography of an interior volume is a challenging, highly ill-posed problem with practical implications in medical and biological imaging, manufacturing, automation, and environmental and food security. Regularizing priors are necessary to reduce artifacts by improving the condition of such problems. Recently, it was shown that one effective way to learn the priors for strongly scattering yet highly structured 3D objects, e.g. layered and Manhattan, is by a static neural network [goy et al. Proc. Natl. Acad. Sci. 116, 19848–19856 (2019)]. Here, we present a radically different approach where the collection of raw images from multiple angles is viewed analogously to a dynamical system driven by the object-dependent forward scattering operator. The sequence index in the angle of illumination plays the role of discrete time in the dynamical system analogy. Thus, the imaging problem turns into a problem of nonlinear system identification, which also suggests dynamical learning as a better fit to regularize the reconstructions. We devised a Recurrent Neural Network (RNN) architecture with a novel Separable-Convolution gated Recurrent Unit (SC-gRU) as the fundamental building block. Through a comprehensive comparison of several quantitative metrics, we show that the dynamic method is suitable for a generic interior-volumetric reconstruction under a limited-angle scheme. We show that this approach accurately reconstructs volume interiors under two conditions: weak scattering, when the Radon transform approximation is applicable and the forward operator well defined;and strong scattering, which is nonlinear with respect to the 3D refractive index distribution and includes uncertainty in the forward operator.

关键词： interior dynamical angular

N-methyl-D-aspartate receptor functions altered by neuronal PTP1B activation in Alzheimer’s disease and schizophrenia models

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Neural Regeneration Research 2022年第10期17卷 2208-2210页

作者： alexandre F.R.Stewart Hsiao-Huei Chen Department of Biochemistry Microbiology and ImmunologyUniversity of Ottawaand University of Ottawa Heart InstituteOttawaONCanada Centre for Infection Immunity and InflammationOttawaONCanada Medicine Cellular and Molecular MedicineUniversity of Ottawa Brain and Mind InstituteOttawa Hospital Research InstituteOttawaONCanada

glutamate is the main exc i tatory neurotransmitter in the brain and binds to two major classes of receptors,theα-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid(AMPA)and the N-methyl-D-aspartate(NMDA)receptors.Unlike AMPA receptors that are immediately activated by glutamate release,NMDA receptors are blocked by magnesium and can only be activated by glutamate after membrane depolarization.Thus,NMDA receptors are only activated after repeated AMPA receptor activation by glutamate.NMDA receptors are,for the most part,calcium-permeable channels.Calcium influx through NMDA receptors modulates synaptic transmission in neurons based on prior history of excitation,and provides a means of scaling the strength of synapses required for Hebbian plasticity.

关键词： PTP1B aspartate NMDA