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Geotechnical particle finite element method for modeling of soilstructure interaction under large deformation conditions

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第3期14卷 967-983页

作者： Josep Maria Carbonell Lluís Monforte Matteo O.Ciantia Marcos Arroyo Antonio Gens MECAMAT Group Department of EngineeringFaculty of Science and TechnologyUniversitat de Vic-Universitat Central de Catalunya(UVic-UCC)VicSpain Centre Internacional de Mètodes Numèrics a l'Enginyeria(CIMNE) BarcelonaSpain School of Science and Engineering University of DundeeDundeeUK universitat Politècnica de Cataluna-BarcelonaTech BarcelonaSpain

The possibilities of the particle finite element method(PFEM)for modeling geotechnical problems are increasingly *** is a numerical approach to solve large displacement and large strain continuum problems that are beyond the capabilities of classical finite element method(FEM).In PFEM,the computational domain is reconfigured for optimal solution by frequent remeshing and boundary *** inherits many concepts,such as a Lagrangian description of continuum,from classic geomechanical *** familiarity with more popular numerical methods facilitates learning and *** work focuses on G-PFEM,a code specifically developed for the use of PFEM in geotechnical *** article has two *** first is to give the reader an overview of the capabilities and main features of the current version of the G-PFEM and the second is to illustrate some of the newer developments of the code.G-PFEM can solve coupled hydro-mechanical static and dynamic problems involving the interaction of solid and/or deformable *** constitutive models for geomaterials are available,including features,such as structure and destructuration,which result in brittle *** solutions are robust,solidly underpinned by numerical technology including mixedfield formulations,robust and mesh-independent integration of elastoplastic constitutive models and a rigorous and flexible treatment of contact *** novel features presented in this work include the contact domain technique,a natural way to capture contact interactions and impose contact constraints between different continuum bodies,as well as a new simplified formulation for dynamic impact *** code performance is showcased by the simulation of several soil-structure interaction problems selected to highlight the novel code features:a rigid footing insertion in soft rock,pipeline insertion and subsequent lateral displacement on over-consolidated clay,screw-pile pull-out and the dyn

关键词： Particle finite element method(PFEM) Structured soils Nonlocal elastoplasticity Contact domain method Soil penetration problems

rate of adverse events of gastroduodenal snare polypectomy for non-flat polyp is low: A prospective and multicenter study

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World Journal of Gastroenterology 2017年第47期23卷 8405-8414页

作者： Henry Córdova Lidia Argüello Carme Loras Antonio Naranjo Rodríguez Faust Riu Pons Joan B Gornals David Nicolás-Pérez Xavier Andújar Murcia Luis Hernández Santos Santolaria Carles Leal Carles Pons Enrique Pérez-Cuadrado-Robles Orlando García-Bosch Michel Papo Berger José Luis Ulla Rocha Cristina Sánchez-Montes Gloria Fernández-Esparrach Endoscopy Unit.Institut de Malalties Digestives Hospital ClínicIDIBAPSCIBERehdUniversitat de Barcelona Digestive Endoscopy Unit Digestive Diseases DepartmentGastrointestinal Endoscopy Research GroupIISLa Fe Polytechnic University Hospital Hospital Universitari Mútua de Terrassa CIBERehd Hospital Reina Sofía Hospital del Mar Hospital Universitari de Bellvitge IDIBELLUniversitat de BarcelonaHospitalet de Llobregat Hospital Universitario de Canarias Hospital Santos Reyes Aranda de Duero Hospital San Jorge Consorci Hospitalari de vic Universitat de Vic Hospital de Viladecans Hospital Morales Meseguer Hospital Moisès Broggi Sant Joan Despí Hospital Joan XXIII Complejo Hospitalario de Pontevedra

AIM To evaluate the rate of adverse events(AEs) during consecutive gastric and duodenal polypectomies in several Spanish centers. METHODS Polypectomies of protruded gastric or duodenal polyps ≥ 5 mm using hot snare were prospectively included. Prophylactic measures of hemorrhage were allowed in predefined cases. AEs were defined and graded according to the lexicon recommended by the American Society for Gastrointestinal Endoscopy. Patients were followed for 48 h, one week and 1 mo after theprocedure. RESULTS308 patients were included and a single polypectomy was performed in 205. Only 36(11.7%) were on prior anticoagulant therapy. Mean polyp size was 15 ± 8.9 mm(5-60) and in 294 cases(95.4%) were located in the stomach. Hemorrhage prophylaxis was performed in 219(71.1%) patients. Nine patients presented AEs(2.9%), and 6 of them were bleeding(n = 6, 1.9%)(in 5 out of 6 AE, different types of endoscopic treatment were performed). Other 24 hemorrhagic episodes could be managed without any change in the outcome of the endoscopy and, consequently, were considered incidents. We did not find any independent risk factor of *** Gastroduodenal polypectomy using prophylactic measures has a rate of AEs small enough to consider this procedure a safe and effective method for polyp resection independently of the polyp size and location.

关键词： Polypectomy Bleeding Adverse events Protruded polyps Gastroduodenal Foregut

The hidden half comes into the spotlight: Peeking inside the black box of root developmental phases

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Plant Communications 2022年第1期3卷 36-52页

作者： Joao Antonio Siqueira Wagner C.Otoni Wagner L.Araujo departamento de Biologia Vegetal Universidade Federal de Vic¸osaVic¸osaMG 36570-900Brazil

Efficient use of natural resources(e.g.,light,water,and nutrients)can be improved with a tailored developmental program that maximizes the lifetime and fitness of *** plant shoots,a developmental phase represents a time window in which the meristem triggers the development of unique morphological and physiological traits,leading to the emergence of leaves,flowers,and *** developmental phases in plant shoots have been shown to enhance food production in crops,this phenomenon has remained poorly investigated in *** light of recent advances,we suggest that root development occurs in three main phases:root apical meristem appearance,foraging,and *** provide compelling evidence suggesting that these phases are regulated by at least four developmental pathways:autonomous,non-autonomous,hormonal,and *** developmental pathways differentially coordinate organ plasticity,promoting morphological alterations,tissue regeneration,and cell death ***,we suggest how nutritional checkpoints may allow progression through the developmental phases,thus completing the root life *** insights highlight novel and exciting advances in root biology that may help maximize the productivity of crops through more sustainable agriculture and the reduced use of chemical fertilizers.

关键词： developmental transitions plasticity cell fates nutritional checkpoints root development root clock

Engineering Improved Photosynthesis in the Era of Synthetic Biology

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Plant Communications 2020年第2期1卷 1-17页

作者： Willian Batista-Silva Paula da Fonseca-Pereira Auxiliadora Oliveira Martins Agustin Zsogon Adriano Nunes-Nesi Wagner L.Araujo departamento de Biologia Vegetal Universidade Federal de Vic¸osaVic¸osaMinas Gerais 36570-900Brazil

Much attention has been given to the enhancement of photosynthesis as a strategy for the optimization of crop *** traditional plant breeding is most likely reaching a plateau,there is a timely need to accelerate improvements in photosynthetic efficiency by means of novel tools and biotechnological *** emerging field of synthetic biology offers the potential for building completely novel pathways in predictable directions and,thus,addresses the global requirements for higher yields expected to occur in the 21st ***,we discuss recent advances and current challenges of engineering improved photosynthesis in the era of synthetic biology toward optimized utilization of solar energy and carbon sources to optimize the production of food,fiber,and fuel.

关键词： photosynthesis synthetic biology genetic engineering yield improvement targeted manipulation

Are the changes in the peripheral brain-derived neurotrophic factor levels due to platelet activation?

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World Journal of Psychiatry 2016年第1期6卷 84-101页

作者： Montserrat Serra-Millàs Osona Mental Health Hospital Universitari de VicSalut Mental i Innovació Social (SaMIS)Universitat de Vic-Universitat Central de Catalunya

Brain-derived neurotrophic factor(BDNF) plays an important role in central nervous system development, neurogenesis and neuronal plasticity. BDNF is also expressed in several non-neuronal tissues, and it could play an important role in other processes, such as cancer, angiogenesis, etc. Platelets are the major source of peripheral BDNF. However, platelets also contain high amounts of serotonin; they express specific surface receptors during activation, and a multitude of pro-inflammatory and immunomodulatory bioactive compounds are secreted from the granules. Until recently, there was insufficient knowledge regarding the relationship between BDNF and platelets. Recent studies showed that BDNF is present in two distinct pools in platelets, in α-granules and in the cytoplasm, and only the BDNF in the granules is secreted following stimulation, representing 30% of the total BDNF in platelets. BDNF has an important role in the pathophysiology of depression. Low levels of serum BDNF have been described in patients with major depressive disorder, and BDNF levels increased with chronic antidepressant treatment. Interestingly, there is an association between depression and platelet function. This review analyzed studies that evaluated the relationship between BDNF and platelet activation and the effect of treatments on both parameters. Only a few studies consider this possible confounding factor, and it could be very important in diseases such as depression, which show changes in both parameters.

关键词： Platelets Brain derived neurotrophic factor depression Antidepressants Biomarkers

Perceived Barriers to Physical Activity and Related Factors in Spanish University Students

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Open Journal of Preventive Medicine 2014年第4期4卷 164-174页

作者： Rodolfo Iván Martínez-Lemos Anna María Puig-Ribera Oscar García-García departament de Ciències de l’Activitat Física Universitat de Vic Barcelona Spain Special Learning department University of Vigo Pontevedra Spain

Objective: The purpose of this study was to identify the influence of readiness of change for physical activity (PA), sociodemographic factors, lifestyle and physical activity status (PAS) on perceived barriers among Spanish university students. Participants: Seven hundred and seventy two (n = 772) men and women ages 17-39 at a north-west regional university in Spain participated in the study. Methods: The International Physical Activity Questionnaire, the States of Change for Physical Activity Behaviour Questionnaire and the Self-perceived Barriers for Physical Activity Questionnaire were used. description, correlation and multiple regression analyses were completed. Results: Participants self-perceived low average-score barriers (2.6 ± 1.4 over 10.0). The 3-higher scores barriers corresponded to “too much work”;“lack of time for exercise” and “laziness”. Gender, PAS and self-perceived health were shown to be associated with perceived barriers. Conclusions: University institutions should consider those factors that predict barriers to PA to develop effective intervention programs.

关键词： University Students Barriers Physical Activity

Soft piezoresistive pressure sensing matrix from copper nanowires composite aerogel

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Science Bulletin 2016年第20期61卷 1624-1630页

作者： Lim Wei Yap Shu Gong Yue Tang Yonggang Zhu Wenlong Cheng department of Chemical Engineering Monash UniversityClayton VIC 3800 Australia Melbourne Centre for Nanofabrication Clayton VIC 3168Australia CSIRO Manufacturing Flagship Clayton VIC 3168 Australia

We report on a simple yet efficient approach to fabricate soft piezoresistive pressure sensors using copper nanowires-based *** sensors exhibit excellent sensitivity and durability and can be easily scalable to form l... 详细信息

关键词： Copper nanowires Aerogel Piezoresistive Pressure sensing matrix

Ultra-small Cu nanoparticles embedded in N-doped carbon arrays for electrocatalytic CO2 reduction reaction in dimethylformamide

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Nano Research 2018年第7期11卷 3678-3690页

作者： Xiaolong Zhang Ying Zhang Fengwang Li Christopher D. Easton Alan M. Bond Jie Zhang School of Chemistry Monash University Clayton 3800 VIC Australia ARC Centre of Excellence for Electromaterials Science Monash University Clayton 3800 VIC Australia CSIRO Manufacturing BayviewAvenue Clayton 3168 VIC Australia

The development of heterogeneous catalysts with a well-defined micro structure to promote their activity and stability for electrocatalyfic CO2 reduction has been shown to be a promising strategy. In this work, Cu nanoparticles （- 4 nm in diameter） embedded in N-doped carbon （Cu@NC） arrays were fabricated by thermal decomposition of copper tetracyanoquinodimethane （CuTCNQ） under N2. Compared to polycrystalline copper electrodes, the Cu@NC arrays provide a significantly improved number of catalytically active sites. This resulted in a 0.7 V positive shift in onset potential, producing a catalytic current density an order magnitude larger at a potential of -2.7 V vs. Fc/Fc＋（Fc = ferrocene） in dimethylformamide （DMF）. By controlling the water content in the DMF solvent, the CO2 reduction product distribution can be tuned. Under optimal conditions （0.5 vol.% water）, 64% HCOO^-, 20% CO, and 13% H2 were obtained. The Cu@NC arrays exhibited excellent catalytic stability with only a 0.5% decrease in the steady-state catalytic current during 6 h of electrolysis. The three-dimensional （3D） array structure of the Cu@NC was demonstrated to be effective for improving the catalytic activity of copper based catalysts while maintaining long-term catalytic stability.

关键词： copper tetracyanoquinodimethane (CuTCNQ) copper carbon arrays CO2 reduction electrocatalysis

Unmet supportive care needs in families of children with chronic health conditions: an Australian cross‑sectional study

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World Journal of Pediatrics 2023年第12期19卷 1181-1191页

作者： Sangeetha Thomas Linda K.Byrne Nicholas P.Ryan Christel Hendrieckx victoria White School of Psychology Faculty of HealthDeakin UniversityMelbourneVIC 3125Australia department of Paediatrics University of MelbourneMelbourneVICAustralia Australian Centre for Behavioural Research in Diabetes MelbourneVICAustralia Institute of Health Transformation Deakin UniversityMelbourneVICAustralia Cancer Council victoria MelbourneVICAustralia

Background The aim of this study was to identify similarities and diferences in the unmet supportive care needs(USCN)of families of children with major chronic health conditions(CHCs)using a universal need assessment *** A cross-sectional online survey involving parents of children with congenital heart disease(CHD),type 1 diabetes mellitus(T1D),cancer,and asthma diagnosed within the last 5 years recruited via social media and support ***-four items assessing the USCN across six domains(care needs,physical and social needs,informational needs,support needs,fnancial needs,child-related emotional needs)were responded to on a 4-point Likert scale[no need(1)to high need(4)].descriptive statistics identifed the level of need,and linear regressions identifed factors associated with higher need domain *** to small numbers,the asthma group was excluded from comparisons across *** One hundred and ninety-four parents completed the survey(CHD:n=97,T1D:n=50,cancer:n=39,and asthma:n=8).Parents of children with cancer were most likely to report at least one USCN(92%),followed by parents of children with T1D(62%).The fve most commonly reported USCN across CHCs were drawn from four domains:child-related emotional,support,care,and *** need items were included in the top fve needs for all conditions.A higher USCN was associated with a greater frequency of hospital visits and the absence of parental *** Using a universal need assessment tool,this is one of the frst studies to characterize USCN in families of children diagnosed with common *** proportions endorsing diferent needs varied across conditions,the most endorsed needs were similar across the illness *** suggests that support programs or services could be shared across diferent CHCs.

关键词： Children Chronic illness Need assessment Unmet supportive care needs