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Proposals of SPT-CPT and DPL-CPT correlations for sandy soils in Brazil

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第6期9卷 1152-1158页

作者： Mirella Dalvi dos Santos Kátia Vanessa Bicalho Universidade Federal do Espírito Santo VitóriaBrazil

Field tests in geotechnical engineering are fundamental for identification of the underground *** standard penetration test(SPT) is the most commonly used geotechnical approach. There has been an increase both in the use and application of the in situ tests: cone penetration test(CPT) and dynamic probing(DP). Several empirical SPT-CPT and dynamic probing light(DPL)-CPT correlations for sandy soils have been discussed in the literature. New SPT-CPT and DPL-CPT correlations for the sandy soils of the city of Vitoria, in the southeast of Brazil, are suggested in this paper. Statistical analyses to evaluate the quality of the data used are performed, and the suggested correlations are validated with several previous published datasets. The paper also provides some insights into SPT-CPT correlations and soil characteristics(i.e. the mean particle size and the fines fraction of the soil).

关键词： Standard penetration test(SPT) Cone penetration test(CPT) Dynamic probing light(DPL) Correlations Sands Statistical evaluations

cabinet of natural curiosities

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Settlement predictions of footings on sands using probabilisticanalysis

作者： (illustrator..1665-1736 )seba Albertus

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Journal of Rock Mechanics and Geotechnical Engineering 2016年第2期8卷 198-203页

作者： felipe carvalho bungenstab kátia vanessa bicalho federal university of espirito santo VitóriaBrazil

The design of footings on sands is often controlled by settlement rather than bearing ***,settlement predictions are essential in the design of shallow ***,predicted settlements of footings are highly dependent on the chosen elastic modulus and the used *** paper presents the use of probabilistic analysis to evaluate the variability of predicted settlements of footings on sands,focusing on the load curve(predicted settlements)*** methodologies,the first-and second-order second-moment(FOSM and SOSM),and Monte carlo simulation(MCS),for calculating the mean and variance of the estimated settlements through Schmertmann(1970)’s equation,are presented and *** soil beneath the footing is treated as an uncorrelated layered material,so the total settlement and variance are found by adding up the increments of the *** deformability modulus(ESi)is considered as the only independent random *** an example of application,a hypothetical case of a typical subsoil in the state of Espirito Santo,southeast of Brazil,is *** results indicate that there is a significant similarity between the SOSM and MCS methods,while the FOSM method underestimates the results due to the non-consideration of the high-order terms in Taylor’s *** contribution of the knowledge of the uncertainties in settlement prediction can provide a safer design.

关键词： Footings Settlements Probabilities Deformability modulus

Use of digital image analysis combined with fractal theory to determine particle morphology and surface texture of quartz sands

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第6期9卷 1131-1139页

作者： Georgia S.Araujo Kátia V.Bicalho Fernando A.Tristao Federal Institute of Education Science and Technology of the State of Espírito SantoBrazil Department of Civil Engineering Federal University of Espírito SantoBrazil

The particle morphology and surface texture play a major role in influencing mechanical and hydraulic behaviors of sandy soils. This paper presents the use of digital image analysis combined with fractal theory as a tool to quantify the particle morphology and surface texture of two types of quartz sands widely used in the region of Vitória, Espírito Santo, southeast of Brazil. The two investigated sands are sampled from different locations. The purpose of this paper is to present a simple, straightforward,reliable and reproducible methodology that can identify representative sandy soil texture *** test results of the soil samples of the two sands separated by sieving into six size fractions are presented and discussed. The main advantages of the adopted methodology are its simplicity, reliability of the results, and relatively low cost. The results show that sands from the coastal spit(BS) have a greater degree of roundness and a smoother surface texture than river sands(RS). The values obtained in the test are statistically analyzed, and again it is confirmed that the BS sand has a slightly greater degree of sphericity than that of the RS sand. Moreover, the RS sand with rough surface texture has larger specific surface area values than the similar BS sand, which agree with the obtained roughness fractal dimensions. The consistent experimental results demonstrate that image analysis combined with fractal theory is an accurate and efficient method to quantify the differences in particle morphology and surface texture of quartz sands.

关键词： Quartz sands Particle morphology and surface texture Image analysis Fractal theory

Age and origin of the Cu（Au—Mo—Ag）Salobo 3A ore deposit,carajás Mineral Province,Amazonian Craton,northern Brazil

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Episodes 2003年第1期26卷 2-9页

作者： Tassinari, Colombo Celso Gaeta Mellito, Kátia Maria Babinski, Marly Centro de Pesquisas Geocronogicas Instituto de Geociências Universidade de São Paulo São Paulo CEP 05588-080 Rua do Lago 562 Brazil

The Salobo 3A polymetallic Cu (Au-Mo-Ag) deposit, located in the southeastern part of the Amazonian Craton, northern Brazil, is hosted by an Archean metavolcano-sedimentary sequence of Salobo Group. The copper mineralization consists of bornite-chalcocite and bornite-chalcopyrite disseminated with magnetite. In this paper we attempt to date the mineralization episodes and to characterize the fluid sources. The stepwise Pb leaching technique applied to chalcocite, tourmaline, chalcopyrite and magnetite yielded 207Pb-206Pb ages of 2705 ± 42 Ma, 2587 ± 150 Ma, 2427 ± 130 Ma, and 2112 ± 12 Ma, respectively. The older age is interpreted as the timing of primary mineralization. Ages of 2.58 Ga and 2.42 Ga are considered to be related to tectonic reactivation of the Itacaiúnas Belt, and the younger age, obtained on late magnetite crystals, suggests the presence of Paleoproterozoic hydrothermal episode. Sm-Nd and Rb-Sr ages of 2.4 and 2.1 Ga were obtained for schists from the Salobo Group and chloritized gneisses of the Xingú Complex, respectively. The strong radiogenic Pb isotopic compositions of all analyzed minerals suggest a continental environment for the mineralizations. Our geochronological results are in agreement with a primary syngenetic origin for the Salobo mineralization, with late remobilization into brittle-ductile structures during a policyclic evolution of the carajás-Cinzento strike-slip system. Low-grade metamorphism and anorogenic granitic plutonism affected the area at ca. 2.1 and 1.8 Ga, respectively.

关键词：铜矿床巴西亚马逊克拉通地块成矿时代成矿作用金钼银矿床

Seamount chains and hotspot tracks:Superficially similar,deeply different

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Geoscience Frontiers 2023年第6期14卷 307-326页

作者： Edgardo cañón-Tapia División de Ciencias de la Tierra CICESE.Carretera Ensenada-Tijuana#3985Ensenada Baja CaliforniaCP 22860Mexico

Nearly 80%of the seafloor extension has not been covered by high-resolution bathymetry,impeding direct observation of ***,lists of seamount location and height at a global scale have been produced using different *** this work four of such databases(publicly available)are compared with each other to assess their *** identify large differences among databases that could have exerted strong influences on models of seamount production and associated geodynamic *** those differences,it is shown that all databases allow the identification of seamount lines both along the present-day Mid Ocean Ridge(MOR)system and on intraplate ***,those seamount lines do not coincide with the so-called hotspot tracks that commonly were defined by selectively focusing attention on the larger *** of all the databases also shows that distinction based only on seamount size between seamounts produced at Mid-Ocean Ridge(MOR)environments from those associated with mantle-plum fed-hotspot activity has been ***,combined with the fact that most seamount lines defined by the available databases can be traced back to past locations of MOR indicates that most of the present-day intraplate linear arrays of seamounts,which include some large seamounts,were not produced by the action of underlying mantle anomalies envisaged in the form of mantle *** evidence presented here calls for a reassessment of the form in which volcanic and tectonic activities are conceptually related to each other.

关键词： Seamount origin Chains of seamounts Spatial distribution of volcanism Intraplate volcanism Mid Ocean Ridge volcanism

Sustainable Laboratory capacity Building in Sierra Leone:From Ebola to COVID-19

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China CDC weekly 2023年第28期5卷 632-636页

作者： Lili Wang Alie Brima tia Bing Xu Xiaopeng Qi Doris Harding Center for Global Public Health Chinese Center for Disease Control and PreventionBeijingChina Sierra Leone-China Friendship Biological Safety Laboratory Ministry of Health and SanitationFreetownSierra Leone Ministry of Health and Sanitation FreetownSierra Leone

The onset of the Ebola outbreak in 2014 originated in Guinea and proceeded to swiftly reach Sierra Leone and Liberia(1).Unfortunately,these nations were critically deficient in their capacity for pathogenic testing and diagnostics,the availability of healthcare workers,and their supply of epidemic prevention materials,thereby impeding their ability to address the outbreak efficiently(2).This grave scenario underscored the need for support from the worldwide community.

关键词： Ebola prevention thereby

Integrative analysis of the inverse expression patterns in pancreas development and cancer progression

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World Journal of Gastroenterology 2019年第32期25卷 4727-4738页

作者： Hong-Liang Zang Guo-Min Huang Hai-Ying Ju Xiao-Feng tia Department of Hepatobiliary and Pancreatic Surgery China-Japan Union Hospital of Jilin UniversityChangchun 130033Jilin ProvinceChina Department of Hematology Jilin Province Blood CenterChangchun 130000Jilin ProvinceChina

BACKGROUND As the malignant tumor,pancreatic cancer with a meager 5-years survival rate has been widely ***,the molecular mechanisms that result in malignant transformation of pancreatic cells remain *** To investigate the gene expression profiles in normal or malignant transformed pancreas *** MaSigPro and ANOVA were performed on two pancreas development datasets downloaded from the Gene Expression Omnibus *** pancreatic cancer datasets collected from TCGA database were used to establish differentially expressed genes related to pancreas development and pancreatic ***,gene clusters with highly similar interpretation patterns between pancreas development and pancreatic cancer progression were established by self-organizing map and singular value ***,the hypergeometric test was performed to compare the corresponding interpretation *** regions of metabolic pathway were analyzed using the Subpathway-GM *** This study established the continuously upregulated and downregulated genes at different stages in pancreas development and progression of pancreatic *** analysis of the differentially expressed genes,we established the inverse and consistent direction development-cancer pattern *** on the application of the Subpathway-GM analysis,we established 17 significant metabolic sub-pathways that were closely associated with pancreatic *** note,the most significant metabolites sub-pathway was related to glycerophospholipid *** The inverse and consistent direction development-cancer pattern associations were *** was a significant correlation in the inverse patterns,but not consistent direction patterns.

关键词： Pancreatic cancer Pancreas development Inverse pattern Metabolites subpathway

Phenazines:Natural products for microbial growth control

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hLife 2024年第3期2卷 100-112页

作者： Cátia A Sousa Marta Ribeiro Francisca Vale Manuel Simões ISEP/P.PORTO School of EngineeringPolytechnic of PortoPortoPortugal LEPABE-Laboratory for Process Engineering EnvironmentBiotechnology and EnergyFaculty of EngineeringUniversity of PortoPortoPortugal ALiCE-Associate Laboratory in Chemical Engineering Faculty of EngineeringUniversity of PortoPortoPortugal

The unprecedented problem of antibiotic resistance has become a major challenge for public health,which has contributed to an increase in infections caused by such *** microbial infections,typically biofilm-related,are alsocoupled to an increase in human mortality and ***,the demand for new antimicrobial agents hasincreased along with the evolution of microbial resistance *** products produced by bacteria,such as phenazines,have been recognized as an important source for the development of new antimicrobial agents,through the exploitation of their capacity to increase oxidative stress in other *** are a large groupof nitrogen-containing heterocyclic compounds and are essential for several cellular processes including iron acquisition,signaling events,enzymatic processes,and biofilm ***-inspired antibiotics(i.e.,2-bromo-1-hydroxyphenazine,2,4-dibromo-1-hydroxyphenazine,bromophenazine-21,phenazine-13,and phenazine-14)are veryactive against a wide range of gram-positive and gram-negative bacteria,including those associated with severe *** this study,mechanisms of phenazine-inspired antibiotics in the cellular processes of planktonic and sessilebacteria are ***,the application of phenazine-inspired antibiotics for the eradication of multidrugresistant planktonic and biofilm bacterial infections is also reviewed.

关键词： antimicrobial agents biofilms multidrug-resistant natural products phenazines