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^(222)Rn calibration procedure for water analyses by liquid scintillation counting

辐射探测技术与方法(英文) 2023年第2期7卷 311-319页

作者： ana rita gomes Sérgio Dias anabela Mourato Joao Abrantes Mário Reis Laboratório de Protecao e Seguranca Radiológica Instituto Superior TécnicoUniversidade de LisboaEstrada Nacional 10km 13972695‑066 Bobadela LRSPortugal Laboratórios de Massa e Massa Volúmica de Sólidos Instituto Portugues da QualidadeRua António Giao22829‑513 CaparicaPortugal Centro de Ciências e Tecnologias Nucleares Instituto Superior TécnicoUniversidade de LisboaEstrada Nacional 10km 13972695‑066 Bobadela LRSPortugal

Purpose Among the several methods to measure ^(222)Rn in water,the liquid scintillation counting(LSC)technique is one of the most sensitive and widely used when analysing non-saline waters by liquid extraction,providing excellent accuracy,precision and low-level detection *** using the liquid scintillation counter Tri-Carb 3170 TR/SL(Perkin-Elmer)it is not possible to make an automatic determination of the alpha/beta discrimination parameter,being necessary to evaluate the pulse decay discriminator(PDD)value manually to the ^(222)Rn *** this work,we describe the steps to perform the calibration of that type of *** The method consists in the preparation of standard samples from a ^(226)Ra certified standard solution and the adjustment of the PDD value by hand until the percentage of alpha events reaches a plateau of a near-constant fraction of total *** process consists in taking several measures between PDD 80 and 200 with 15 min counting time *** the plateau,the alpha/beta ratio was used to determine the plateau final range as well as the optimum PDD *** that,the calibration standards and blanks were measured and the region of interest(ROI)was established by finding the maximum value for the figure of merit(FOM)in the upper and lower *** The optimal PDD value of 148 was established by the alpha/beta ratio,and after that,it was possible to measure ^(226)Ra standards to perform the *** efficiency of(9.758±0.035)×1^(0-1) was *** routine measurements,a detection limit of about 0.50 Bq L^(-1) is achieved for a 120 min counting *** evaluate the uncertainty budget,the uncertainties of the net count rate,the efficiency,the sample amount and the decay correction factor were *** A method was developed for the calibration of LSC Tri-Carb 3170 TR/SL with the optimization of the PDD using a ^(226)Ra standard *** acquisition to obtain the plot of the variation

关键词： Radon Waters Pulse decay discriminator Liquid scintillation counting Calibration

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Emerging role of liquid biopsy in rat sarcoma virus mutated metastatic colorectal cancer:A case report

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 234-243页

作者： João Gramaça Isabel gomes Fernandes Carolina Trabulo Joana Gonçalves rita Gameiro dos Santos Adriano Baptista Idília Pina Centro Hospitalar Barreiro Montijo Centro Hospitalar Barreiro MontijoSetúbalBarreiro 2830-003Portugal Medical Oncology Unit Centro Hospitalar Barreiro MontijoSetúbalBarreiro 2830-003Portugal

BACKGROUND In patients with metastatic colorectal cancer(mCRC),the treatment options are limited and have been proved to be affected by rat sarcoma virus(RAS)mutational *** RAS wild-type(wt)patients,the combination of antiepidermal growth factor receptor(EGFR)monoclonal antibodies with chemotherapy(CT)is more effective than CT *** the other hand,RAS-mutated patients are not eligible for treatment with anti-EGFR *** SUMMARY Eleven patients with initially RAS-mutated mCRC were followed from diagnosis to May *** the time of cell-free DNA determination,five patients had undergone one CT line,five patients had undergone two CT lines,and one patient had undergone three CT lines(all in combination with bevacizumab).At the second and third treatment lines[second line(2L),third line(3L)],patients with neo-RAS wt received a combination of CT and *** neo-RAS wt patients treated with anti-EGFR,our findings indicated an increase in progression-free survival for both 2L and 3L(14.5 mo,P=0.119 and 3.9 mo,P=0.882,respectively).Regarding 2L overall survival,we registered a slight increase in neo-RAS wt patients treated with anti-EGFR(33.6 mo vs 32.4 mo,P=0.385).At data cut-off,two patients were still alive:A RAS-mutated patient undergoing 3L treatment and a neo-RAS wt patient who received 2L treatment with anti-EGFR(ongoing).CONCLUSION Our case series demonstrated that monitoring RAS mutations in mCRC by liquid biopsy may provide an additional treatment line for neo-RAS wt patients.

关键词： Metastatic colorectal cancer Rat sarcoma virus mutational status Liquid biopsy Rat sarcoma virus wild-type Neo-rat sarcoma virus wild-type Anti-epidermal growth factor receptor therapy Case report

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Mixed iridium-nickel oxides supported on antimony-doped tin oxide as highly efficient and stable acidic oxygen evolution catalysts

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Materials Futures 2024年第1期3卷 165-180页

作者： Jonathan Ruiz Esquius Alec P LaGrow Haiyan Jin Zhipeng Yu ana Araujo rita Marques Adélio Mendes Lifeng Liu Clean Energy Cluster International Iberian Nanotechnology LaboratoryAv.Mestre JoséVeigaBraga 4715-330Portugal Carbon Science and Technology Institute INCAR-CSICFrancisco Pintado Fe 26Oviedo 33011Spain Scientific Imaging Section Okinawa Institute of Science and Technology Graduate UniversityKunigami-gunOkinawa 904-0412Japan Songshan Lake Materials Laboratory Dongguan 523808People’s Republic of China Laboratory for Process Engineering EnvironmentBiotechnology and EnergyFaculty of EngineeringUniversity of PortoRua Dr Roberto FriasPorto 4200-465Portugal Associate Laboratory in Chemical Engineering Faculty of EngineeringUniversity of PortoRua Dr Roberto FriasPorto 4200-465Portugal.

Proton exchange membrane(PEM)water electrolysis represents a promising technology for green hydrogen production,but its widespread deployment is greatly hindered by the indispensable usage of platinum group metal catalysts,especially iridium(Ir)based materials for the energy-demanding oxygen evolution reaction(OER).Herein,we report a new sequential precipitation approach to the synthesis of mixed Ir-nickel(Ni)oxy-hydroxide supported on antimony-doped tin oxide(ATO)nanoparticles(IrNiyO_(x)/ATO,20 wt.%(Ir+Ni),y=0,1,2,and 3),aiming to reduce the utilisation of scarce and precious Ir while maintaining its good acidic OER *** tested in strongly acidic electrolyte(0.1 M HClO_(4)),the optimised IrNi1Ox/ATO shows a mass activity of 1.0 mAµgIr^(−1) and a large turnover frequency of 123 s^(−1) at an overpotential of 350 mV,as well as a comparatively small Tafel slope of 50 mV dec^(−1),better than the IrOx/ATO control,particularly with a markedly reduced Ir loading of only 19.7µgIr cm^(−2).Importantly,IrNi1O_(x)/ATO also exhibits substantially better catalytic stability than other reference catalysts,able to continuously catalyse acidic OER at 10 mA cm^(−2) for 15 h without obvious *** in-situ synchrotron-based x-ray absorption spectroscopy confirmed that the Ir^(3+)/Ir^(4+)species are the active sites for the acidic ***,the performance of IrNi1Ox/ATO was also preliminarily evaluated in a membrane electrode assembly,which shows better activity and stability than other reference *** IrNi1Ox/ATO reported in this work is a promising alternative to commercial IrO_(2) based catalysts for PEM electrolysis.

关键词： mixed oxides oxygen evolution reaction polymer electrolyte membrane antimony doped tin oxide membrane electrode assembly

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Motivations for and barriers to innovation in non-profit organizations: The case of nursing homes in Northern Portugal

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International Journal of Innovation Studies 2024年第1期8卷 25-44页

作者： ana rita Gonçalves Lopes Aldina Isabel de Azevedo Correia Alexandra Maria da Silva Braga Center for Research and Innovation in Business Sciences and Information Systems School of Management and TechnologyPolitecnico do PortoRua do Curral-Margaride4610-156 FelgueirasPortugal

To contribute to the empirical literature on innovation in non-profit organizations,this study examines innovation in Private Social Solidarity Institutions with social responses for the elderly in Northern *** enriches the literature by clarifying the concept of innovation applied to non-profit organizations,which represents a perspective different from the business ***,it is important to support the innovation decisionmaking process in similar non-profit *** this study,the population was surveyed through questionnaires based on the PUBLIN research project,which has already been applied in different countries,and the targets were employees of organizations with social responses for the *** sample is small,with 28 respondent institutions and 51 employees,but it is representative,as it includes institutions from all districts in Northern *** study employed a quantitative approach,particularly factor analysis,multiple linear regression,and correlation analyses,using scales already applied in other dimensions of the social sector,to understand the effect of each innovation dimension/determinant on creativity and innovation in nonprofit *** results show that in these organizations with social responses for the elderly,learning orientation,risk-taking,and job satisfaction have a positive impact on innovation.

关键词： Determinants of innovation non-profit organizations social responses for the elderly Northern Portugal

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Is magnesium deficiency the major cause of needle chlorosis of Pinus taeda in Brazil?

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Journal of Forestry Research 2024年第2期35卷 209-221页

作者： Antônio Carlos Vargas Motta Shizuo Maeda Valdécio dos Santos dos Santos Rodrigues Tamires Maiara Ercole Stephen Arthur Prior ana Elisa Lyra Brumat Amanda Pacheco Cardoso Moura Julierme Zimmer Barbosa João Bosco Vasconcellos gomes Department of Soil Sciences and Agriculture Engineering Federal University of ParanáR.dos Funcionários1540.CuritibaParanáCEP 80035‑050Brazil Brazilian Agricultural Research Company Embrapa FlorestasEstr.da Ribeira–Br‑476Km 111–Parque Monte Castelo.ColomboParanáCEP 83411‑000Brazil United States Department of Agriculture‑Agricultural Research Service USDA-ARS National Soil Dynamics Laboratory411 South Donahue DriveAuburnAL 36832USA Reforestation Remasa Rodovia PR 170–Km 522.BiturunaParanáCEP 84640‑000Brazil Federal Institute of Southeast of Minas Gerais R.Luz Interior360.Juiz de ForaMinas Gerais CEP 36030‑713Brazil

Needle chlorosis(NC)in Pinus taeda *** in Brazil becomes more frequent after second and third harvest rotation *** a study to identify factors contributing to yellowing needle chorosis(YNC),trees were grown in soils originating from contrasting parent materials,and soils and needles(whole,green and chlorotic portions)from 1-and 2-year-old branches and the first and second needle flush release at four sites with YNC on *** were analyzed for various elements and *** soils had very low base levels(Ca^(2+),Mg^(2+)and K^(+))and P,suggesting a possible lack of multiple *** symptoms started at needle tips,then extended toward the needle base with *** flush needles had longer portions with YNC than second flush needles *** from the lower crown also had more symptoms along their length than those higher in the *** were similar to those reported for *** chlorotic portions,Mg and Ca concentrations were well below critical values;in particular,Mg levels were only one third of the critical value of 0.3 g kg^(-1).Collectively,results suggest that Mg deficiency is the primary reason for NC of *** in various parent soils in Brazil.

关键词： Nutritional deficiency Forest management Soil depletion Pine foliar analysis Needle chlorosis

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The biosynthetic pathway of the hallucinogen mescaline and its heterologous reconstruction

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Molecular Plant 2024年第7期17卷 1129-1150页

作者： Paula Berman Luis Alejandro de Haro ana-rita Cavaco Sayantan Panda Younghui Dong Nikolay Kuzmich Gabriel Lichtenstein Yoav Peleg Hila Harat Adam Jozwiaki Jianghua Cai Uwe Heinig Sagit Meir Ilana Rogachev Asaph Aharoni Department of Plant and Environmental Sciences Weizmann Institute of ScienceRehovot 7610001Israel Life Sciences Core Facilities Weizmann Institute of ScienceRehovot 7610001Israel The Maurice and Vivienne Wohl Institute for Drug Discovery Weizmann Institute of ScienceRehovot 7610001Israel Present address:Department of Cell and Metabolic Biology Leibniz Institute of Plant BiochemistryWeinberg 306120 Halle(Saale)Germany Department of Molecular&Cellular Pharmacology University of Miami Miler School of MedicineMiamiFL 33136USA Department of Botany and Plant Sciences University of California RiversideRiversideCA 92521USA Laboratory of Plant Hormones and Development Regulation of Chongqing School of Life SciencesChongqing UniversityChongqing 401331China

Mescaline,among the earliest identified natural hallucinogens,holds great potential in psychotherapy ***,despite the existence of a postulated biosynthetic pathway for more than half a century,the specific enzymes involved in this process are yet to be *** this study,we investigated the cactus Lophophora williamsii(Peyote),the largest known natural producer of the phenethylamine *** employed a multi-faceted approach,combining de novo whole-genome and transcriptome sequencing with comprehensive chemical profiling,enzymatic assays,molecular modeling,and pathway engineering for pathway *** identified four groups of enzymes responsible for the six catalytic steps in the mescaline biosynthetic pathway,and an N-methyltransferase enzyme that N-methylates all phenethylamine intermediates,likely modulating mescaline levels in ***,we reconstructed the mescaline biosynthetic pathway in both Nicotiana benthamiana plants and yeast cells,providing novel insights into several challenges hindering complete heterologous mescaline *** together,our study opens up avenues for exploration of sustainable production approaches and responsible utilization of mescaline,safeguarding this valuable natural resource for future generations.

关键词： mescaline Lophophora williamsi Peyote biosynthetic pathway de novo genome sequencing mo-lecular modeling

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Interactive Model Used in Maintenance Planning of Facades Based on Virtual Reality Technology

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Journal of Civil Engineering and Architecture 2012年第10期6卷 1292-1309页

作者： Alcinia Zita Sampaio Augusto M. gomes ana rita gomes Department of Civil Engineering and Architecture Technical University of Lisbon Lisbon 1049-001 Portugal

A virtual reality model was created in order to help in the maintenance of exterior closures and interior finishes of walls in a building. It allows the visual and interactive transmission of information related to the physical behavior of the elements, defined as a function of the time variable. To this end, the basic knowledge of material most often used in walls, anomaly surveillance, techniques of rehabilitation, and inspection planning were studied. This information was included in a database that supports the periodic inspection needed in a program of preventive maintenance. The results are obtained interactively and visualized in the virtual environment itself. This work brings an innovative contribution to the field of maintenance supported by emergent technology.

关键词：虚拟现实技术建筑物维护规划外墙动模虚拟现实模型预防性维护室内装饰

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Molecular mechanisms underlying the neuroprotection of environmental enrichment in Parkinson’s disease

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Neural Regeneration Research 2023年第7期18卷 1450-1456页

作者： Tamara Andrea Alarcón Sarah Martins Presti-Silva ana Paula Toniato Simões Fabiola Mara Ribeiro rita gomes Wanderley Pires Department of Physiological Sciences Health Science CenterUniversidade Federal do Espirito SantoVitoriaBrazil Laboratory of Molecular and Behavioral Neurobiology Health Science CenterUniversidade Federal do Espirito SantoVitoriaBrazil Department of Biochemistry and Immunology Institute o Biological SciencesUniversidade Federal de Minas GeraisAvenida Antônio CarlosBelo HorizonteBrazil

Parkinson’s disease is the most common movement disorder,affecting about 1%of the population over the age of 60 ***’s disease is characterized clinically by resting tremor,bradykinesia,rigidity and postural instability,as a result of the progressive loss of nigrostriatal dopaminergic *** addition to this neuronal cell loss,Parkinson’s disease is characterized by the accumulation of intracellular protein aggregates,Lewy bodies and Lewy neurites,composed primarily of the proteinα-*** it was first described almost 200 years ago,there are no disease-modifying drugs to treat patients with Parkinson’s *** addition to conventional therapies,non-pharmacological treatment strategies are under investigation in patients and animal models of neurodegenerative *** such strategies,environmental enrichment,comprising physical exercise,cognitive stimulus,and social interactions,has been assessed in preclinical models of Parkinson’s *** enrichment can cause structural and functional changes in the brain and promote neurogenesis and dendritic growth by modifying gene expression,enhancing the expression of neurotrophic factors and modulating *** this review article,we focus on the current knowledge about the molecular mechanisms underlying environmental enrichment neuroprotection in Parkinson’s disease,highlighting its influence on the dopaminergic,cholinergic,glutamatergic and GABAergic systems,as well as the involvement of neurotrophic *** describe experimental pre-clinical data showing how environmental enrichment can act as a modulator in a neurochemical and behavioral context in different animal models of Parkinson’s disease,highlighting the potential of environmental enrichment as an additional strategy in the management and prevention of this complex disease.

关键词： acetylcholine brain-derived neurotrophic factor dopamine environment enrichment gamma-aminobutyric acid glial cell line-derived neurotrophic factor glutamate molecular mechanisms Parkinson’s disease

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A geomechanics classification for the rating of railroad subgrade performance

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Railway Engineering Science 2022年第3期30卷 323-359页

作者： Antonio gomes Correia ana Ramos Department of Civil Engineering ISISEUniversity of MinhoGuimara˜esPortugal

The type of subgrade of a railroad foundation is vital to the overall performance of the track *** the train speed and tonnage increase,as well as environmental changes,the evaluation and influence of subgrade are even more paramount in the railroad track structure performance.A geomechanics classification for subgrade is proposed coupling the stiffness(resilient modulus)and permanent deformation behaviour evaluated by means of repeated triaxial loading *** classification covers from fine-to coarse-grained soils,grouped by UIC and *** this achievement,we first summarize the main models for estimating resilient modulus and permanent deformation,including the evaluation of their robustness and their sensitivity to mechanical and environmental *** is followed by the procedure required to arrive at the geomechanical classification and rating,as well as a discussion of the influence of environmental *** work is the first attempt to obtain a new geomechanical classification that can be a useful tool in the evaluation and modelling of the foundation of railway structures.

关键词： Subgrade Resilient modulus Permanent deformation Geomechanical classification

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Influence of train speed and its mitigation measures in the short-and long-term performance of a ballastless transition zone

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铁道工程科学:英文版 2023年第4期31卷 309-324页

作者： ana Ramos Rui Calçada António gomes Correia Department of Civil Engineering Faculty of EngineeringUniversity of PortoCONSTRUCT-LESEPortoPortugal Department of Civil Engineering University of MinhoISISEGuimarãesPortugal

The ballastless track is nowadays the most popular railway system due to the required low number of maintenance opera-tions and costs,despite the high *** gradual change from ballasted to ballastless tracks has been occurring in Asia,but also in Europe,increasing the number of transition *** transition zones are a special area of the railway networks where there is an accelerated process of track degradation,which is a major concern of the railway infrastructure ***,the accurate prediction of the short-and long-term performance of ballastless tracks in transition zones is an important topic in the current paradigm of building/rehabilitating high-speed *** work purposes the development of an advanced 3D model to study the global performance of a ballastless track in an embankment-tunnel transition zone considering the influence of the train speed(220,360,500,and 600 km/h).Moreover,a mitigation measure is also adopted to reduce the stress and displacements levels of the track in the transition.A resilient mat placed in the tunnel and embank-ment aims to soften the *** behaviour of the track with the resilient mat is evaluated considering the influence of the train speed,with special attention regarding the critical *** used methodology is a novel and hybrid approach that allows including short-term and long-term performance,through the development of a powerful 3D model combined with the implementation of a calibrated empirical permanent deformation model.

关键词： Ballastless track Train speed Numerical modelling Transition zone Critical speed

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