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Journal of Pharmaceutical Analysis 2023年第11期13卷 1346-1352页

作者： Jaime Millan-Santiago rafael Lucena Soledad cardenas Affordable and Sustainable Sample Preparation(AS2P)Research Group Analytical Chemistry DepartmentChemical Institute for Energy and Environment(IQUEMA)University of CordobaE-14071CordobaSpain

This study proposes a hypodermic needle(HN)as a sorbent holder and an electrospray(ESI)emitter,thus combining extraction and analysis in a single device.A novel nylon 6-cellulose(N6-cel)composite sorbent is proposed to extract methadone from oral fluid *** cellulosic substrate provides the composite with high porosity,permitting the flow-through of the sample,while the polyamide contributes to the extraction of the *** low price of the devices(considering the holder and the sorbent)contributes to the affordability of the method,and their small size allows easy transportation,opening the door to on-site *** the optimum conditions,the analyte can be determined by high-resolution ambient ionization mass spectrometry at a limit of detection(LOd)as low as 0.3 mg/L and precision(expressed as relative standard deviation,RSd)better than 9.3%.The trueness,expressed as relative recovery(RR),ranged from 90%to 109%.As high-resolution mass spectrometers are not available in many laboratories,the method was also adapted to low-resolution *** this sense,the direct infusion of the eluates in a triple quadrupole-mass spectrometry provided an LOd of 2.2 mg/*** RSd was better than 5.3%,and the RR ranged from 96%to 121%.

关键词： ESI emitter Mass spectrometry Hypodermic needle composite Methadone

Multiple ecological strategies explain the distribution of exotic and native c_(4) grasses in heterogeneous early successional sites in Hawai’i

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Journal of Plant Ecology 2017年第3期10卷 426-439页

作者： rafael de Oliveira Xavier carla M.d’Antonio Ecology and conservation Lab Department of HydrobiologyFederal University of São CarlosWashington Luís Highwaykm 235São CarlosSão Paulo 13565-905Brazil Environmental Studies Program 4312-L Bren University of CaliforniaSanta BarbaraCA 93106USA

Aims Biotic homogenization results in novel communities contain-ing multiple exotic *** attributes that contribute to the dominance of invaders and increase invasibility of communities have been identified,but rarely have factors governing the domi-nance of co-occurring invaders been *** we assess the presence and performance of five exotic and one native c_(4) grass species across local(microsite)and more broad-scale variation in fire history,soil age,altitude and *** ask whether species show preferences for the same conditions,whether all are constrained by poor soil development,and how their performance changes when alone versus *** addition to providing information useful to managers who want to control some of these species,such information can help to predict how distributions might change with climate change Methods We measured percent cover and plant height of each grass species in 64 plots in each of 15 sites,located in young volcanic substrates across environmental gradients in Hawai’i Volcanoes National Park,Hawai’i,*** varied in fire history and soil age,across altitu-dinal and precipitation *** estimated microsite heteroge-neity by measuring rock cover and soil depth,where each species was present and in plots as a *** analyzed effects of pos-sible controlling variables using chi-square tests and Generalized Additive Mixed *** Findings Two species(Schizachyrium condensatum and Hyparrhenia rufa)were absent in shallow soil,restricted to more mesic sites and showed increasing performance with soil *** contrast,two other species(Andropogon virginicus and Melinis repens)tended to occur in shal-low soil with high rock cover across a wide range of *** addi-tional species(Melinis minutiflora)was weakly affected by soil depth and was the dominant at higher elevation(more mesic)and on burned sites,especially in old *** species was largely absent from lower elevation si

关键词： elevation gradient fire invasive species Melinis minutiflora soil depth

Effects of natural mineral-rich water consumption on the expression of sirtuin 1 and angiogenic factors in the erectile tissue of rats with fructose-induced metabolic syndrome

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Asian Journal of Andrology 2014年第4期16卷 631-638页

作者： cidalia d Pereira Milton Severo Luisa rafael Maria Joao Martins delminda Neves department of Biochemistry Faculty of Medicine University of Porto department of clinical Epidemiology Predictive Medicine and Public Health Faculty of Medicine University of Porto department of clinical Pathology Sao Joao Hospital Centre EPE department of Experimental Biology Faculty of Medicine and Institute for Molecular and Cell Biology (IBMC) University of Porto Portugal.

consuming a high-fructose diet induces metabolic syndrome （MS）-Iike features, including endothelial dysfunction. Erectile dysfunction is an early manifestation of endothelial dysfunction and systemic vascular disease. Because mineral deficiency intensifies the deleterious effects of fructose consumption and mineral ingestion is protective against MS, we aimed to characterize the effects of 8weeks of natural mineral-rich water consumption on the structural organization and expression of vascular growth factors and receptors on the corpus cavernosum （cc） in 10% fructose-fed Sprague-dawley rats （FRUcT）. differences were not observed in the organization of the cc either on the expression of vascular endothelial growth factor （VEGF） or the components of the angiopoietins/Tie2 system. However, opposing expression patterns were observed for VEGF receptors （an increase and a decrease for VEGFR1 and VEGFR2, respectively） in FRUcT animals, with these patterns being strengthened by mineral-rich water ingestion. Mineral-rich water ingestion （FRUcTMIN） increased the proportion of smooth muscle cells compared with FRUcT rats and induced an upregulatory tendency of sirtuin I expression compared with the control and FRUcT groups. Western blot results were consistent with the dual immunofluorescence evaluation. Plasma oxidized low-density lipoprotein and plasma testosterone levels were similar among the experimental groups, although a tendency for an increase in the former was observed in the FRUcTMIN group. The mineral-rich water-treated rats presented changes similar to those observed in rats treated with MS-protective polyphenol-rich beverages or subjected to energy restriction, which led us to hypothesize that the effects of mineral-rich water consumption may be more vast than those directly observed in this study.

关键词： angiopoietins erectile tissue hypersaline sodium-rich naturally sparkling mineral water receptors sirtuin 1 vascularendothelial growth factor

climate-driven variations in productivity reveal adaptive strategies in Iberian cork oak agroforestry systems

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Forest Ecosystems 2022年第1期9卷 83-93页

作者： José carlos Pérez-Girón Emilio rafael díaz-Varela Pedro Álvarez-Álvarez department of Organisms and Systems Biology Polytechnic School of MieresUniversity of OviedoE-33600MieresAsturiasSpain Research Group on Planning and Management in complex Adaptive Socio-Ecological Systems(cOMPASSES).School of Engineering University of Santiago de CompostelaE-27002LugoSpain

Background:cork oak agroforestry systems(AFS)have been managed for centuries by humans to produce cork and other goods and services and have recently been recognised as an important reservoir for biodiversity improvement and ***,despite having recently been included as a natural habitat of community-wide interest within the EU Habitats directive,these systems are in a critical situation of *** other factors,they are strongly threatened by climate change,the effects of which are also expected to be particularly severe in the Mediterranean *** this study,we aimed to evaluate the influence of climate variability by examining primary production indicators and also to analyse whether the geographical location may have a role in the incidence of the adverse effects of ***:cork oak AFS were identified in the Forest Map of Spain and the Land use map of Portugal and categorized on the basis of canopy *** climate data from 2001 to 2020 were used to model relationships with climate predictors and proximity to the *** analysis was conducted to identify significant spatial clusters of high-and low-efficiency ***:The responses to the influence of climatic conditions differed among the various cork oak AFS categories,particularly in the forest category,which was less dependent on climate *** humidity and water availability were the main drivers of net primary production(NPP).carbon use efficiency(cUE)was limited by relative humidity and spring temperature in open *** to the coast proved beneficial,especially in years with adverse weather conditions,but was not a limiting factor for survival of the ***,the results of the hotspot analysis supported the other findings,highlighting high-efficiency areas close to the coast and cold spots grouped in specific areas or dispersed ***:canopy plays a key role in the influence of climatic conditions,particu

关键词： Net primary production carbon use efficiency climate Quercus suber Agroforestry system

Artificial neural network with a cross-validation approach to blast-induced ground vibration propagation modeling

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Underground Space 2021年第3期6卷 281-289页

作者： Gustavo Paneiro Manuel rafael dEcivil/cERENA Tecnico LisboaULisboaPortugal Orica Mining Services Portugal Portugal

Given their technical and economic advantages,the application of explosive substances to rock mass excavation is widely ***,because of serious environmental restraints,there has been an increasing need to use complex tools to control environmental effects due to blast-induced ground *** the present study,an artificial neural network(ANN)with k-fold cross-validation was applied to a dataset containing 1114 observations that was obtained from published results;furthermore,quantitative and qualitative parameters were considered for ground vibration amplitude *** best ANN model obtained has a maximum coefficient of determination of 0.840 and a mean absolute error of 5.59 and it comprises 17 input parameters,12 neurons in a one-layer hidden layer,and a sigmoid transfer *** with the traditional models,the model obtained using the proposed methodology demonstrated better generalization ***,the proposed methodology offers an ANN model with higher prediction ability.

关键词： Rock blasting Excavation Ground vibrations Artificial neural network K-fold cross-validation Modeling

Proteomics and the genetics of sperm chromatin condensation

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Asian Journal of Andrology 2011年第1期13卷 24-30页

作者： rafael Oliva Judit castillo Human Genetics Research Group IDI BAPS Department of Ciencias Fisiologicas I Faculty of Medicine University of Barcelona Barcelona 08036 Spain Biochemistry and Molecular Genetics Service Hospital Clinic i Provincial Barcelona 08036 Spain

Spermatogenesis involves extremely marked cellular, genetic and chromatin changes resulting in the generation of the highly specialized sperm cell. Proteomics allows the identification of the proteins that compose the spermatogenic cells and the study of their function. The recent developments in mass spectrometry （MS） have markedly increased the throughput to identify and to study the sperm proteins. catalogs of thousands of testis and spermatozoan proteins in human and different model species are becoming available, setting up the basis for subsequent research, diagnostic applications and possibly the future development of specific treatments. The present review intends to summarize the key genetic and chromatin changes at the different stages of spermatogenesis and in the mature sperm cell and to comment on the presently available proteomic studies.

关键词： epigenetic imprinting protamine proteome spermatozoa

Envelopes of commutative Rings

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Acta Mathematica Sinica,English Series 2012年第3期28卷 561-580页

作者： rafael PARRA Manuel SAORIN departamento de clculo. Escuela Bsica Facultad de Ingeniería Universidad de los Andes departamento de Matemticas Universidad de Murcia

Given a significative class F of commutative rings, we study the precise conditions under which a commutative ring R has an S-envelope. A full answer is obtained when F is the class of fields, semisimple commutative rings or integral domains. When .F is the class of Noetherian rings, we give a full answer when the Krull dimension of R is zero and when the envelope is required to be epimorphic. The general problem is reduced to identifying the class of non-Noetherian rings having a monomorphic Noetherian envelope, which we conjecture is the empty class.

关键词： Noetherian ring envelope local ring artinian ring Krull dimension

chemically Induced and Light-Independent cryptochrome Photoreceptor Activation

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Molecular Plant 2008年第1期1卷 4-14页

作者： Gesa Rosenfeldt rafael Munoz Viana Henning d. Mootz Albrecht G. von Arnim Alfred Batschauera FB Biologie-pflanzenphysiologie Philipps-Universitat Karl-von-Frisch-Str. 8 35032 Marburg Germany Universitat dortmund FB Chemie-Chemische Biologie Otto-Hahn-Str. 6 44227 Dortmund Germany University of Tennessee Department of Biochemistry Cellular and Molecular Biology Waiters Life Sciences M407 Knoxville TN 37996-0840 USA

The cryptochrome photoreceptors of higher plants are dimeric proteins. Their N-terminal photosensory domain mediates dimerization, and the unique c-terminal extension （ccT） mediates signaling. We made use of the human FK506binding protein （FKBP） that binds with high affinity to rapamycin or rapamycin analogs （rapalogs）. The FKBP-rapamycin complex is recognized by another protein, FRB, thus allowing rapamycin-induced dimerization of two target proteins. Here we demonstrate by bioluminescence resonance energy transfer （BRET） assays the applicability of this regulated dimer- ization system to plants. Furthermore, we show that fusion proteins consisting of the c-terminal domain of Arabidopsis cryptochrome 2 fused to FKBP and FRB and coexpressed in Arabidopsis cells specifically induce the expression of cryptochrome-controlled reporter and endogenous genes in darkness upon incubation with the rapalog. These results demonstrate that the activation of cryptochrome signal transduction can be chemically induced in a dose-dependent fashion and uncoupled from the light signal, and provide the groundwork for gain-of-function experiments to study specifically the role of photoreceptors in darkness or in signaling cross-talk even under light conditions that activate members of all photoreceptor families.

关键词： c-terminal extension (ccT) FK506-binding protein (FKBP) bioluminescence resonance energy transfer (BRET)

Single-model uncertainty quantification in neural network potentials does not consistently outperform model ensembles

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npj computational Materials 2023年第1期9卷 49-59页

作者： Aik Rui Tan Shingo Urata Samuel Goldman Johannes c.B.dietschreit rafael Gómez-Bombarelli department of Materials Science and Engineering Massachusetts Institute of TechnologyCambridgeMAUSA Innovative Technology Laboratories AGC IncTokyoJapan computational and Systems Biology Massachusetts Institute of TechnologyCambridgeMAUSA

Neural networks(NNs)often assign high confidence to their predictions,even for points far out of distribution,making uncertainty quantification(UQ)a *** they are employed to model interatomic potentials in materials systems,this problem leads to unphysical structures that disrupt simulations,or to biased statistics and dynamics that do not reflect the true *** UQ techniques can find new informative data and drive active learning loops for robust ***,a variety of UQ techniques,including newly developed ones,exist for atomistic simulations and there are no clear guidelines for which are most effective or suitable for a given *** this work,we examine multiple UQ schemes for improving the robustness of NN interatomic potentials(NNIPs)through active *** particular,we compare incumbent ensemble-based methods against strategies that use single,deterministic NNs:mean-variance estimation(MVE),deep evidential regression,and Gaussian mixture models(GMM).We explore three datasets ranging from in-domain interpolative learning to more extrapolative out-of-domain generalization challenges:rMd17,ammonia inversion,and bulk silica *** is measured across multiple metrics relating model error to *** experiments show that none of the methods consistently outperformed each other across the various *** remained better at generalization and for NNIP robustness;MVE only proved effective for in-domain interpolation,while GMM was better out-of-domain;and evidential regression,despite its promise,was not the preferable alternative in any of the *** broadly,cost-effective,single deterministic models cannot yet consistently match or outperform ensembling for uncertainty quantification in NNIPs.

关键词： ensemble evident neural

On the Base Point Locus of Surface Parametrizations:Formulas and consequences

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communications in Mathematics and Statistics 2022年第4期10卷 757-783页

作者： david A.cox Sonia Pérez-díaz J.rafael Sendra department of Mathematics and Statistics Amherst CollegeAmherstMA 01002USA Universidad de Alcalá Dpto.de Física y Matemáticas28871 MadridSpain

This paper shows that the multiplicity of the base point locus of a projective rational surface parametrization can be expressed as the degree of the content of a univariate *** a consequence,we get a new proof of the degree formula relating the degree of the surface,the degree of the parametrization,the base point multiplicity and the degree of the rational map induced by the *** addition,we extend both formulas to the case of dominant rational maps of the projective plane and describe how the base point loci of a parametrization and its reparametrizations are *** an application of these results,we explore how the degree of a surface reparametrization is affected by the presence of base points.

关键词： Base point Hilbert-Samuel multiplicity Surface parametrization Reparametrization Parametrization degree Surface degree