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The Study of Carbamoyl Phosphate Synthetase 1 Deficiency Sheds Light on the Mechanism for Switching On/Off the Urea Cycle

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Journal of Genetics and Genomics 2015年第5期42卷 249-260页

作者： Carmen Díez-Fernández José Gallego Johannes H?berle Javier Cervera vicente Rubio Institute for Biomedicine of Valencia of the Spanish Research Council Medical School of the Catholic University of Valencia University Children's Hospital Zurich and Children's Research Center Centre for Biomedical Networking Research on Rare Diseases of the Carlos Ⅲ Health Institute

Carbamoyl phosphate synthetase i （CPS1） deficiency （CPS1D） is an inborn error of the urea cycle having autosomal （2q34） recessive inheritance that can cause hyperammonemia and neonatal death or mental retardation. We analyzed the effects on CPS1 activity, kinetic parameters and enzyme stability of missense mutations reported in patients with CPS1 deficiency that map in the 20-kDa C-terminal domain of the enzyme. This domain turns on or off the enzyme depending on whether the essential allosteric activator of CPS 1, N-acetyl- L-glutamate （NAG）, is bound or is not bound to it. To carry out the present studies, we exploited a novel system that allows the expression in vitro and the purification of human CPS1, thus permitting site-directed mutagenesis. These studies have clarified disease causation by individual mutations, identifying functionally important residues, and revealing that a number of mutations decrease the affinity of the enzyme for NAG. Patients with NAG affinity-decreasing mutations might benefit from NAG site saturation therapy with N-carbamyl-L- glutamate （a registered drug, the analog of NAG）. Our results, together with additional present and prior site-directed mutagenesis data for other residues mapping in this domain, suggest an NAG-triggered conformational change in the 134-~4 loop of the C-terminal domain of this enzyme. This change might be an early event in the NAG activation process. Molecular dynamics simulations that were restrained according to the observed effects of the mutations are consistent with this hypothesis, providing further backing for this structurally plausible signaling mechanism by which NAG could trigger urea cycle activation via CPS1.

关键词： Urea cycle diseases Inborn errors Hyperammonemia Site-directed mutagenesis Restrained molecular dynamics Allosteric regulation Carbamoyl phosphate synthetase 1 Enzyme

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Performance of masonry enclosure walls:lessons learned from recent earthquakes

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Earthquake Engineering and Engineering Vibration 2012年第1期11卷 23-34页

作者： Romeu Silva vicente Hugo Rodrigues Humberto Varum Aníbal Costa Jos António Raimundo Mendes da Silva University of Aveiro Civil Engineering Department Campus Universitario de SantiagoAveiroPT3810-193Portugal University of Coimbra Civil Engineering Pinhal de MarrocosPolo ⅡCoimbraPT3030Portugal

This paper discusses the issue of performance requirements and construction criteria for masonry enclosure and infill walls. Vertical building enclosures in European countries are very often constituted by non-load-bearing masonry walls, using horizontally perforated clay bricks. These walls are generally supported and confined by a reinforced concrete frame structure of columns and beams/slabs. Since these walls are commonly considered to be nonstructural elements and their influence on the structural response is ignored, their consideration in the design of structures as well as their connection to the adjacent structural elements is frequently negligent or insufficiently detailed. As a consequence, nonstructural elements, as for wall enclosures, are relatively sensitive to drift and acceleration demands when buildings are subjected to seismic actions. Many international standards and technical documents stress the need for design acceptability criteria for nonstructural elements, however they do not specifically indicate how to prevent collapse and severe cracking, and how to enhance the overall stability in the case of moderate to high seismic loading. Furthermore, a review of appropriate measures to improve enclosure wall performance and both in-plane and out-of-plane integrity under seismic actions is addressed.

关键词： RC structures masonry enclosure walls infill walls in-plane out-of-plane cracking performanceimprovement

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A comparative study of the morphometry of sperm head components in cattle, sheep, and pigs with a computer-assisted fluorescence method

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Asian Journal of Andrology 2016年第6期18卷 840-843页

作者： Jesus L Yaniz Sara Capistros Sandra vicente-Fiel Carlos O Hidalgo Pilar Santolaria TECNOGAM research group Environmental Sciences Institute (IUCA) Department of Animal Production and Food Sciences University of Zaragoza Huesca Spain Animal Genetics and Reproduction Area Regional Agrifood Research and Development Service (SERIDA) 33394 Deva Gijan Spain

The aim of this study was to compare the sperm nuclear and acrosomal morphometry of three species of domestic artiodactyls; cattle （Bos taurus）, sheep （Ovis aries）, and pigs （Sus scrofa）. Semen smears of twenty ejaculates from each species were fixed and labeled with a propidium iodide-Pisum sativum agglutinin （PI/PSA） combination. Digital images of the sperm nucleus, acrosome, and whole sperm head were captured and analyzed. The use of the PI/PSA combination and CASA-Morph fluorescence-based method allowed the capture, morphometric analysis, and differentiation of most sperm nuclei, acrosomes and whole heads, and the assessment of acrosomal integrity with a high precision in the three species studied. For the size of the head and nuclear area, the relationship between the three species may be summarized as bull 〉 ram 〉 boar. However, for the other morphometric parameters （length, width, and perimeter）, there were differences in the relationships between species for sperm nuclei and whole sperm heads. Bull sperm acrosomes were clearly smaller than those in the other species studied and covered a smaller proportion of the sperm head. The acrosomal morphology, small in the bull, large and broad in the sheep, and large, long, and with a pronounced equatorial segment curve in the boar, was species-characteristic. It was concluded that there are clear variations in the size and shape of the sperm head components between the three species studied, the acrosome being the structure showing the most variability, allowing a clear distinction of the spermatozoa of each species.

关键词： artiodactyls computer-assisted sperm morphometry analysis fluorescence microscopy image analysis sperm morphometry

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Kinetic behaviour of commercial catalysts for methane reforming in ethanol steam reforming process

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Journal of Energy Chemistry 2014年第5期23卷 639-644页

作者： Jorge vicente Javier Erea Martin Olazar Pedro L.Benito Javier Bilbao Ana G.Gayubo Departamento de Ingeniería Química Universidad del País Vasco UPV/EHU Apartado 644 48080 Bilbao Spain Departamento de Ingeniería Minera y Metalúrgica y Ciencia de los Materiales Universidad del País Vasco UPV/EHUNieves Cano 12 01006 Vitoria-Gasteiz Spain

Ethanol steam reforming has been studied in a fluidized bed （in order to ensure bed isothermicity） on commercial catalysts for methane reforming. The results allow analyzing the effect of temperature （in 300-700℃ range）, and both metal and support nature on the reaction indices （ethanol conversion, yields and selectivities to H2 and byproducts （CO2, CO, CH4 and C2H4O））. Special attention has been paid to catalysts＇ stability by comparing the evolution of the reaction indices with time on stream at 500°C （minimum CO formation） and 700℃ （minimum deactivation by coke deposition）. Although they provide a slightly lower H2 yield, the results evidence a good behaviour of Ni based catalysts, indicating that they are an interesting alternative of more expensive Rh based ones.

关键词： ethanol steam reforming hydrogen commercial catalyst selectivity deactivation

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Performance Estimation of Machine Learning Algorithms in the Factor Analysis of COVID-19 Dataset

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Computers, Materials & Continua 2021年第2期66卷 1921-1936页

作者： Ashutosh Kumar Dubey Sushil Narang Abhishek Kumar Satya Murthy Sasubilli vicente García-Díaz Chitkara University Institute of Engineering and Technology Chitkara UniversityPunjabIndia Workday Integration Architect Huntington ColumbusOHUSA Department of Computer Science University of OviedoOviedoSpain

Novel Coronavirus Disease(COVID-19)is a communicable disease that originated during December 2019,when China officially informed the World Health Organization(WHO)regarding the constellation of cases of the disease in the city of ***,the disease started spreading to the rest of the *** this point in time,no specific vaccine or medicine is available for the prevention and cure of the *** research works are being carried out in the fields of medicinal and pharmaceutical sciences aided by data analytics and machine learning in the direction of treatment and early detection of this viral *** present report describes the use of machine learning algorithms[Linear and Logistic Regression,Decision Tree(DT),K-Nearest Neighbor(KNN),Support Vector Machine(SVM),and SVM with Grid Search]for the prediction and classification in relation to *** data used for experimentation was the COVID-19 dataset acquired from the Center for Systems Science and Engineering(CSSE),Johns Hopkins University(JHU).The assimilated results indicated that the risk period for the patients is 12–14 days,beyond which the probability of survival of the patient may *** addition,it was also indicated that the probability of death in COVID cases increases with *** death probability was found to be higher in males as compared to *** with Grid search methods demonstrated the highest accuracy of approximately 95%,followed by the decision tree algorithm with an accuracy of approximately 94%.The present study and analysis pave a way in the direction of attribute correlation,estimation of survival days,and the prediction of death *** findings of the present study clearly indicate that machine learning algorithms have strong capabilities of prediction and classification in relation to COVID-19 as well.

关键词： COVID-19 linear and logistic regression DT KNN SVM SVMwith grid search

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Dynamically generated resonances from the vector octet-baryon decuplet interaction and their radiative decays into γ-baryon decuplet

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Chinese Physics C 2009年第12期33卷 1366-1368页

作者：孙宝玺 Sourav Sarkar E. Oset M.J. vicente Vacas Institute of Theoretical Physics College of Applied Sciences Beijing University of Technology Departamento de Física Teórica and IFIC Centro Mixto Universidad de Valencia-CSIC Institutos de Investigación de Paterna Aptdo. 22085 46071 Valencia Spain Variable Energy Cyclotron Centre 1/AF Bidhannagar

The dynarnically generated resonances from vector meson-baryon decuplet are studied using La- grangians of the hidden gauge theory for vector interactions. One shows that some of the generated states can be associated with some known baryon resonances in the PDG data, while others are predictions for new states. Furthermore, we calculate the radiative decay widths of these resonances into a photon and a baryon decuplet.

关键词： dynamically generated resonances chiral dynamics hidden gauge formalism for vector mesoninteraction

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Emerging artificial intelligence applications in liver magnetic resonance imaging

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World Journal of Gastroenterology 2021年第40期27卷 6825-6843页

作者： Charles E Hill Luca Biasiolli Matthew D Robson vicente Grau Michael Pavlides Department of Engineering Science University of OxfordOxford OX37DQUnited Kingdom Radcliffe Department of Medicine University of OxfordOxford OX39DUUnited Kingdom MR Physics Perspectum LtdOxford OX42LLUnited Kingdom Department of Engineering University of OxfordOxford OX37DQUnited Kingdom Oxford Centre for Clinical Magnetic Resonance Research Division of Cardiovascular MedicineRadcliffe Department of MedicineUniversity of OxfordOxford OX39DUUnited Kingdom Translational Gastroenterology Unit University of OxfordOxford OX39DUUnited Kingdom Oxford NIHR Biomedical Research Centre University of OxfordOxford OX39DUUnited Kingdom

Chronic liver diseases(CLDs)are becoming increasingly more prevalent in modern *** use of imaging techniques for early detection,such as magnetic resonance imaging(MRI),is crucial in reducing the impact of these diseases on healthcare *** intelligence(AI)algorithms have been shown over the past decade to excel at image-based analysis tasks such as detection and *** applied to liver MRI,they have the potential to improve clinical decision making,and increase throughput by automating *** Liver diseases becoming more prevalent in society,the need to implement these techniques to utilize liver MRI to its full potential,is *** this review,we report on the current methods and applications of AI methods in liver MRI,with a focus on machine learning and deep learning *** assess four main themes of segmentation,classification,image synthesis and artefact detection,and their respective potential in liver MRI and the wider *** provide a brief explanation of some of the algorithms used and explore the current challenges affecting the *** there are many hurdles to overcome in implementing AI methods in the clinic,we conclude that AI methods have the potential to positively aid healthcare professionals for years to come.

关键词： Liver diseases Magnetic resonance imaging Machine learning Deep learning Artificial intelligence Computer vision

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Low-cost disordered carbons for Li/S batteries： A high- performance carbon with dual porosity derived from cherry pits

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Nano Research 2018年第1期11卷 89-100页

作者： Celia Hernandez-Rentero Rafael Cordoba Noelia Moreno Alvaro Caballero Julian Morales Mara Olivares-Marin vicente Gomez-Serrano Dpto. Ouimica Inorgdnica e Ingenierfa Quimica Instituto de Quimica Fina y Nanoqufmica Universidad de C6rdoba 14071 C6rdoba Spain Dpto. Quimica Inorg6nica Facultad de Ciencias Universidad de Extremadura 06006 Badajoz Spain

A micro- and mesoporous carbon obtained from cherry pit waste and activated with HBPO4 acid has been studied as the sulfur host for Li/S batteries. The carbon has a high specific surface area of 1,662 m2·g-1 （SBET） and micropore and mesopore volumes of 0.57 and 0.40 cm3·g-1, respectively. The S/C composite, with a sulfur content of 57% deposited by the disproportionate reaction of a SaO2- solution in an acid medium without an additional heating step above the S melting point, delivers an initial specific capacity of 1,148 mah·g-1 at a current of C/16. It also has a high capacity retention of 915 mAh·g-1 after 100 cycles and a Coulombic efficiency close to 100%. The good performance of the composite was also observed under higher current rates and long-term cycling tests. The capacities delivered by the cell after 200 cycles were 707 and 410 mAh·g-1 at C/2 and 1C （1C = 1,675 mA·g-1）, respectively, maintaining the high Coulombic efficiency. The overall electrochemical response of this carbon as the sulfur matrix is among the best reported so far among the other biomass-derived carbons, probably because of the micro- and mesopore system formed upon activation.

关键词： activated carbon agricultural waste cherry stone sulfur composite lithium-sulfur batteries

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Hydrocarbons in particulate samples from wildfire events in central Portugal in summer 2010

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Journal of Environmental Sciences 2017年第3期29卷 122-131页

作者： Ana vicente Ana Calvo Ana P.Fernandes Teresa Nunes Cristina Monteiro Casimiro Pio Célia Alves Centre for Environmental and Marine Studies (CESAM) Department of EnvironmentUniversity of Aveiro Department of Physics IMARENABUniversity of León

In summer 2010, twenty eight （14 PM=2.5 samples plus 14 samples PM2.5-10） smoke samples were collected during wildfires that occurred in central Portugal. A portable high-volume sampler was used to perform the sampling, on quartz fibre filters of coarse （PM=2.5-10） and fine （PM2.5） smoke samples. The carbonaceous content （elemental and organic carbon） of particulate matter was analysed by a thermal-optical technique. Subsequently, the particulate samples were solvent extracted and fractionated by vacuum flash chromatog- raphy into three different classes of organic compounds （aliphatics, polycyclic aromatic hydrocarbons （PAHs） and carbonyl compounds）. The organic speciation was performed by gas chromatography-mass spectrometry （GC-MS）. Emissions were dominated by the fine particles, which represented around 92% of the PM10. A clear predominance of carbonaceous constituents was observed, with organic to elemental carbon （OC/EC） ratios ranging between 1.69 and 245 in both size fractions. The isoprenoid ketone 6,10,14-trimethyl-2-pentadecanone, a tracer for secondary organic aerosol formation, was one of the dominant constituents in both fine and coarse particles. Retene was the most abundant compound in all samples. Good correlations were obtained between OC and both aliphatic and PAH compounds. Pyrogenic processes, thermal release of biogenic com- pounds and secondary processing accounted for 97% of the apportioned PM2.5 levels.

关键词： WildfiresOrganic carbonOrganic compoundsBiomarkersParticulate matterPortugal

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Deep diving in the PACIFIC:Practical issues in stage III non-small cell lung cancer to avoid shipwreck

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World Journal of Clinical Oncology 2020年第11期11卷 898-917,I0003页

作者： Xabier Mielgo-Rubio Federico Rojo Laura Mezquita-Pérez Francesc Casas Amadeo Wals Manel Juan Carlos Aguado Javier Garde-noguera David vicente Felipe Couñago Department of Medical Oncology Hospital Universitario Fundación AlcorcónMadrid 28922Spain Department of Pathology IIS-Jiménez Díaz-CIBERONC FoundationMadrid 28040Spain Department of Medical Oncology Hospital ClinicLaboratory of Translational Genomics and Targeted Therapeutics in Solid TumorsIDIBAPSBarcelona 08036Spain Department of Radiation Oncology Hospital ClinicBarcelona 08036Spain Department of Radiation Oncology Hospital Universitario Virgen MacarenaSevilla 41009Spain Department of Immunology Service Hospital ClínicUniversitat de BarcelonaBarcelona 08036Spain Department of Medical Oncology Hospital Universitario Clínico San CarlosMadrid 28040Spain Department of Medical Oncology Hospital Universitario Virgen MacarenaSevilla 49001Spain Department of Radiation Oncology Hospital Universitario Quirónsalud MadridHospital La LuzUniversidad Europea de MadridMadrid 28028Spain

After publication of the PACIFIC trial results,immune checkpoint inhibitor-based immunotherapy was included in the treatment algorithm of locally advanced non-small cell lung cancer(NSCLC).The PACIFIC trial demonstrated that 12 mo of durvalumab consolidation therapy after radical-intent platinum doublet chemotherapy with concomitant radiotherapy improved both progression-free survival and overall survival in patients with unresectable stage III *** is the first treatment in decades to successfully improve survival in this clinical setting,with manageable toxicity and without deterioration in quality of *** integration of durvalumab in the management of locally advanced NSCLC accentuates the need for multidisciplinary,coordinated decision-making among lung cancer specialists,bringing new challenges and controversies as well as important changes in clinical work *** aim of the present article is to review—from a practical,multidisciplinary perspective—the findings and implications of the PACIFIC *** evaluate the immunobiological basis of durvalumab as well as practical aspects related to programmed cell death ligand 1 *** addition,we comprehensively assess the efficacy and toxicity data from the PACIFIC trial and discuss the controversies and practical aspects of incorporating durvalumab into routine clinical ***,we discuss unresolved questions and future *** short,the present document aims to provide clinicians with a practical guide for the application of the PACIFIC regimen in routine clinical practice.

关键词： Durvalumab Non-small cell lung cancer PACIFIC Immunotherapy Immune checkpoint inhibitors Anti-programmed cell death ligand 1 Consolidation therapy Unresectable stage III lung cancer

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