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Indirect determination of shear wave velocity in slow formations using full-wave sonic logging technique

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journal of Rock Mechanics and Geotechnical Engineering 2020年第6期12卷 1226-1233页

作者： francisco Beltran Alvaro Yañez-Gonzalez María j.Crespo Belgar Engineering Consultants Gabriel García Márquez 9Collado-Villalba28400Spain ESTEYCO Menéndez Pidal 17Madrid28036Spain Principia Engineering Consuxltants Velázquez 94Madrid28006Spain

This article presents a case study concerning a seismic characterization ***-wave sonic logging was used to characterize the shallow compressional wave and shear wave velocity profiles in the *** values of the Poisson’s ratio derived from the velocity profiles suggested that the boreholes might have traversed slow formations(*** shear wave velocity smaller than the borehole fluid compressional wave velocity or“mud-wave speed”)and that conventional processing of the sonic logs might have misinterpreted the direct arrivals of fluid acoustic waves as arrivals caused by shear wave propagation in the ***,the shear wave velocity profiles provided by the contractor were considered to be unreliable by the project *** address these problems,a non-conventional determination of the shear wave velocity was implemented,based on the relationship between the Poisson’s ratio of the rock formation and the shape of the first train of sonic waves which arrived to the receivers in the sonic *** relationship was determined based on several hundreds of finite element simulations of the acoustic wave propagation in boreholes with the same diameter as used in the *** present article describes how this non-conventional approach was developed and implemented to obtain the shear wave velocity profiles from the raw sonic *** approach allows an extension of the range of applicability of full-wave sonic logging to determination of shear wave velocity profiles in formations with low compressional wave *** method could be used to obtain shear wave velocity profiles where compressional wave velocity is as low as slightly larger than the mud-wave speed.A sample sonic log in log ASCII Standard(lAS)format is provided as supplementary material to this paper via Mendeley Data,together with the FORTRAN source code used to process the log following the approach described in this study.

关键词： Sonic logging Slow formation Shear wave velocity Poisson’s ratio P-wave packet

Alifanov迭代修正法估计非线性热传导未知热源函数

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检验检疫科学 2005年第6期15卷 17-19页

作者：王甲正张灿 Antonio j.silva Neto francisco D.Moura Neto 北京出入境检验检疫局重庆大学城市建设与环境工程学院巴西里约州立大学Nova Friburgo应用技术研究所

本文介绍热传导反问题中未知热源函数Alifanov迭代修正法估计的详细步骤;介绍了应用共轭梯度法的过程中,求解残差平方函数梯度的过程;并介绍了非线性估计的应用实例。

关键词：函数估计热传导反问题共轭梯度法非线性估计源函数修正法迭代平方函数应用残差

Are Runners More Prone to Become Infected with COVID-19?An Approach from the Raindrop Collisional Model

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journal of Science in Sport and Exercise 2021年第2期3卷 167-170页

作者： francisco j.Arias Department of Fluid Mechanics Polytechnic University of CataloniaESEIAAT C/Colom 1108222 BarcelonaSpain

It is known that COVID-19 spread mainly from person-to-person through respiratory droplets produced when an infected person coughs or sneezes,and as a result certain ideas about contagious of COVID-19 have been *** of them is the widespread belief that close runners,owing to the stronger exhalation,can be more prone to be infected with COVID-19 because the collision with the suspended respiratory droplets should the runner in front be ***,because of the low Stokes number this idea cannot be generalized without carefully thought and in fact can be put into *** the raindrop collisional model and with the help of computational fluid dynamics (CFD),it is shown that the probability of collision with respiratory droplets is not always increasing with the approaching velocity of the runner but rather there is a maximum velocity threshold at which the efficiency of collision drops.

关键词： COVID-19 contagious airbone Spread diseases

Counter-regulatory phosphatases TNAP and NPP1 temporally regulate tooth root cementogenesis

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International journal of Oral Science 2015年第1期7卷 27-41页

作者： laura E Zweifler Mudita K Patel francisco H Nociti jr Helen F Wimer jose l Milln Martha j Somerman Brian l Foster National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) National Institutes of Health (NIH) Department of Prosthodontics and Periodontics Division of Periodontics School of Dentistry Campinas State University Department of Vertebrate Zoology National Museum of Natural History Smithsonian Institution Sanford Children’s Health Research Center Sanford-Burnham Medical Research Institute

Cementum is critical for anchoring the insertion of periodontal ligament fibers to the tooth root. Several aspects of cementogenesis remain unclear, including differences between acellular cementum and cellular cementum, and between cementum and bone. Biomineralization is regulated by the ratio of inorganic phosphate （Pi） to mineral inhibitor pyrophosphate （PPi）, where local Pi and PPi concentrations are controlled by phosphatases including tissue-nonspecific alkaline phosphatase （TNAP） and ectonucleotide pyrophosphatase/phosphodiesterase 1 （NPP1）. The focus of this study was to define the roles of these phosphatases in cementogenesis. TNAP was associated with earliest cementoblasts near forming acellular and cellular cementum. With loss of TNAP in the Alpl null mouse, acellular cementum was inhibited, while cellular cementum production increased, albeit as hypomineralized cementoid. In contrast, NPP1 was detected in cementoblasts after acellular cementum formation, and at low levels around cellular cementum. loss of NPP1 in the Enppl null mouse increased acellular cementum, with little effect on cellular cementum. Developmental patterns were recapitulated in a mouse model for acellular cementum regeneration, with early TNAP expression and later NPP1 expression. In vitro, cementoblasts expressed Alpl gene/protein early, whereas Enppl gene/protein expression was significantly induced only under mineralization conditions. These patterns were confirmed in human teeth, including widespread TNAP, and NPP1 restricted to cementoblasts lining acellular cementum. These studies suggest that early TNAP expression creates a low PPi environment promoting acellular cementum initiation, while later NPP1 expression increases PPi, restricting acellular cementum apposition. Alterations in PPi have little effect on cellular cementum formation, though matrix mineralization is affected.

关键词： cementum bone ectonucleotide pyrophosphatase phosphodiesterase 1 periodontal ligament progressive ankylosis protein tissue-nonspecific ajkaljne phosphatase

CaMKH binding to GluN2B is critical for memory consolidation

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CaMKH binding to GluN2B is critical for memory consolidation

Seismic performance of composite moment-resisting frames achieved with sustainable CFST members

中国生理学会第23届全国会员代表大会暨生理学学术大会

作者： Amy R.Halt R.F.Dallapiazza j.W.Hell Alcino j.silva Departments of Pharmacology and Psychiatry and Neurosurgery Roy J.and Lucille A.Carver College of MedicineUniversity of IowaIowa CityIA 52242USA Department of Neurobiology Semel InstituteDepartment of PsychologyBrain Research InstituteUniversity of CaliforniaLos AngelesCalifornia90095USA

Memory is essential for our normal daily lives and our sense of ***,our knowledge of molecular and cellular mechanisms of memory formation and retention is *** influx through the NMDA-type glutamate receptor(NMDAR) and the ensuing activation of the Ca and calmodulin-dependent protein kinase(CaMKII) are required for memory formation and its physiological correlate,long-term potentiation(lTP).The Ca influx induces CaMKII binding to the NMDAR to strategically recruit CaMKII to synapses that are undergoing potentiation. We show that mice with two point mutations that impair CaMKII binding to the NMDAR GluN2B subunit initially learn the Morris water maze and acquire contextual fear conditioning under standard conditions to the same degree as wild type mice but show deficiency during the period of early memory consolidation in these ***, the activity-driven interaction of CaMKII with the NMDAR is important for imprinting memory traces.

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Frontiers of Structural and Civil Engineering 2016年第3期10卷 312-332页

作者： A. silva Y. jIANG l. MACEdo j. M. CASTRO R. MONTEIRO N. SIlVESTRE Department of Civil Engineering Faculty of Engineering University of Porto Porto 4099-002 Portugal Istituto Universitario di Studi Superiori di Pavia Pavia 27100 Italy IDMEC LAETA Department of Mechanical Engineering Instituto Superior Tecnico Universidade de Lisboa Lisboa 1649-004 Portugal

The main objective of the research presented in this paper is to study the bending behaviour of Concrete Filled Steel Tube （CFST） columns made with Rubberized Concrete （RuC）, and to assess the seismic performance of moment-resisting frames with these structural members. The paper describes an experimental campaign where a total of 36 specimens were tested, resorting to a novel testing setup, aimed at reducing both the preparation time and cost of the test specimens. Different geometrical and material parameters were considered, namely cross-section type, cross-section slenderness, aggregate replacement ratio, axial load level and lateral loading type. The members were tested under both monotonic and cyclic lateral loading, with different levels of applied axial loading. The test results show that the bending behaviour of CFST elements is highly dependent on the steel tube properties and that the type of infill does not have a significant influence on the flexural behaviour of the member. It is also found that Eurocode 4 is conservative in predicting the flexural capacity of the tested specimens. Additionally, it was found that the seismic design of composite moment- resisting frames with CFST columns, according to Eurocode 8, not only leads to lighter design solutions but also to enhanced seismic performance in comparison to steel frames.

关键词： concrete filled steel tubes rubberized concrete composite frames seismic performance assessment

Entropy model to assess sediment resuspension probability and trap efficiency of small dams

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International journal of Sediment Research 2022年第5期37卷 675-686页

作者： francisco jairo Soares Pereira Antonio Viana da silva Filho josé Wellington Batista lopes josé Carlos de Araújo Department of Agricultural Engineering Federal University of Ceará Campus Do Pici Rural Federal University of Pernambuco Federal University of Piauí

In the Brazilian drylands, there are tens of thousands of small dams. Despite their paramount importance to the rural population, they are rarely monitored. Water demand increases with time while, simultaneously, siltation reduces reservoir water capacity and availability. Reservoir siltation models are, therefore, mandatory to manage the numerous ungauged small dams in these *** objective of the current study is to improve sediment trap efficiency(TE) modeling by including resuspension as a key probabilistic process. The Shannon entropy was used to estimate the sediment resuspension probability, which was merged with the Camp model and generated the RETSED entropy model. To validate the RETSED model, an experimental check dam(ECD, 300 m3), located in the Gilbu es desertification site, Brazil, was monitored hourly during one hydrological year(july 2018-july 2019). Measurements show that the annual volumetric decline of the check dam was 12%; and that the average trap efficiency equaled 86%. Only 9.5% of the hourly sediment concentration outflow exceeded the average plus one standard deviation, showing that the reservoir is well mixed; a fact which highlights the relevance of the resuspension process. Three empirical models failed to mimic the experimental results: Churchill(TE = 99%), Brune(TE = 75%), and Maryland(TE = 94%). According to the RETSED entropy model, the resuspension probability during the experiment was 10%and TE = 81%, a value only 6% below the measured one. The Camp model simulated TE = 89%, only 3%higher than the measured value, but confirmed the Camp model’s tendency to overestimate TE due to a disregard of resuspension. The deterministic model showed low sensitivity concerning the hydrodynamic effects, whereas the entropy formulation proved to be more consistent with physical behavior: the resuspension probability clearly increased and trap efficiency decreased with rising reservoir discharge.

关键词： Erosion Check dam Sedimentation Ungauged basins Camp model

Recombinant streptokinase vs phenylephrine-based suppositories in acute hemorrhoids, randomized, controlled trial(THERESA-3)

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World journal of Gastroenterology 2014年第6期20卷 1594-1601页

作者： francisco Hernández-Bernal Georgina Castellanos-Sierra Carmen M Valenzuela-silva Karem M Catasús-lvarez Roselin Valle-Cabrera Ana Aguilera-Barreto Pedro A lópez-Saura Center for Genetic Engineering and Biotechnology "juan B. Zayas" Hospital National Center for the Coordination of Clinical Trials

AIM: To compare the efficacy and safety of recombinant streptokinase (rSK) and phenylephrine-based suppositories in acute hemorrhoidal disease.

关键词： Streptokinase Suppository Phenylephrine Thrombolysis Hemorrhoids Randomized clinical trial

Siderophore-Producing Rhizobacteria as a Promising Tool for Empowering Plants to Cope with Iron limitation in Saline Soils:A Review

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Pedosphere 2019年第4期29卷 409-420页

作者： Maria j.FERREIRA Helena silva Angela CUNHA Biology Department and Centre for Environmental and Marine Studies(CESAM) University of Aveiro Campus de Santigo

Iron(Fe) bioavailability to plants is reduced in saline soils;however, the exact mechanisms underlying this effect are not yet completely understood. Siderophore-expressing rhizobacteria may represent a promising alternative to chemical fertilizers by simultaneously tackling salt-stress effects and Fe limitation in saline soils. In addition to draught, plants growing in arid soils face two other major challenges: high salinity and Fe deficiency. Salinity attenuates growth, affects plant physiology, and causes nutrient imbalance,which is, in fact, one of the major consequences of saline stress. Iron is a micronutrient essential for plant development, and it is required by several metalloenzymes involved in photosynthesis and respiration. Iron deficiency is associated with chlorosis and low crop productivity. The role of microbial siderophores in Fe supply to plants and the effect of plant growth-promoting rhizobacteria(PGPR) on the mitigation of saline stress in crop culture are well documented. However, the dual effect of siderophore-producing PGPR, both on salt stress and Fe limitation, is still poorly explored. This review provides a critical overview of the combined effects of Fe limitation and soil salinization as challenges to modern agriculture and intends to summarize some indirect evidence that argues in favour of siderophore-producing PGPR as biofertilization agents in salinized soils. Recent developments and future perspectives on the use of PGPR are discussed as clues to sustainable agricultural practices in the context of present and future climate change scenarios.

关键词： aridity bioavailability biofertilizer Fe deficiency high salinity plant growth-promoting rhizobacteria(PGPR) saline stress soil salinization