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Bacterial Sample Concentration and Culture Monitoring Using a PEG-Based Osmotic System with Inline Impedance and Voltammetry Measurements

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Journal of Analysis and Testing 2019年第2期3卷 166-174页

作者： Martin K.Kimani John Mwangi edgar d.goluch department of Chemical Engineering Northeastern UniversityBostonMA 02115USA department of Bioengineering Northeastern UniversityBostonMA 02115USA

Impedance measurements using graphite electrodes were used to detect the increase in culture medium conductivity due to bacteria growth in real time along with simultaneous voltammetric monitoring of pyocyanin *** methods were compared to conventional continuous monitoring of bacterial cultures using turbidity measurement at an optical density of 600 nm(Od600).A practical osmotic system was further designed for concentrating bacterial cultures during growth to enable earlier detection using the electrochemical *** cultures,starting from an initial culture density of 1×10^(8) cells/mL,were grown inside a sealed cellulose ester dialysis membrane,while polyethylene glycol in LB medium was used as the draw solution outside the membrane to gradually concentrate the growing cultures.0.7-mm-diameter graphite for mechanical pencils was utilized as working and counter electrodes with a platinum wire reference electrode for electrochemical measurements with and without the osmotic *** the absence of forward osmosis,impedance meas-urements detected culture growth~1 h faster than conventional *** osmosis showed a twofold decrease in the time to detect pyocyanin production as an indicator for bacterial *** impedance monitoring,removal of water by osmosis was conflated with the impedance decrease due to cell growth;however,the results show a promising ability to detect bacteria growth via an observed shift in osmotic impedance profile when bacteria are present in a *** monitoring the deviation in the impedance profile,a threefold improvement in detection time was achieved when compared to conventional Od600 measurements.

关键词： Osmotic concentration Pseudomonas aeruginosa Bacterial growth detection Impedance electrochemical monitoring Forward osmosis

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Nonlinear numerical assessment of the seismic response of hillside RC buildings

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Earthquake Engineering and Engineering Vibration 2021年第2期20卷 423-440页

作者： Miguel A.Gómez edgar Giovanny díaz-Segura Juan Carlos Vielma Civil Engineering School Pontificia Universidad Católica de ValparaísoValparaíso 2340000Chile

Major damage has been reported in hilly areas after major earthquakes,primarily because of two special conditions:the variation in the seismic ground motion due to the inclined ground surface and the irregularities caused by a stepped base level in the *** aim of this study is to evaluate possible differences in the responses of Chilean hillside buildings through numerical linear-elastic and nonlinear *** the first step,a set of response-spectrum analyses were performed on four simplified 2d structures with mean base inclination angles of 0°,15°,30°,and 45°.The structures were designed to comply with Chilean seismic codes and standards,and the primary response parameters were *** assess the seismic performance of the buildings,nonlinear static(pushover)and dynamic(time-history)analyses were performed with SeismoStruct *** analyses were used to compare the nonlinear response at the maximum roof displacement and the damage ***-history analyses were performed to assess the nonlinear dynamic response of the structures subjected to seismic ground motions modified by topographic *** consider the topographic modification,acceleration records were obtained from numerical models of soil,which were calculated using the rock acceleration record of the Mw 8.01985 Chilean *** differences in the structure responses(roof displacements and maximum element forces and moments)were caused by the topographic effects in the seismic input motion,with the highly predominant ones being the differences caused by the step-back configuration at the base of the *** concentrations of shear forces in short walls were observed,corresponding to the walls located in the upper zone of the foundation *** response of the structures with higher angles was observed to be more prone to fragile failures due to the accumulation of shear *** though hillside buildings gain stiffness in the lower stories,resulting

关键词： topographic effect hillside buildings nonlinear analyses shear-wall buildings

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Assessment of compressive strength of jet grouting by machine learning

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 102-111页

作者： Esteban diaz edgar Leonardo Salamanca-Medina Roberto Tomas departamento de Ingeniería Civil Escuela Politécnica SuperiorUniversidad de AlicanteP.O.Box 99E-03080AlicanteSpain

Jet grouting is one of the most popular soil improvement techniques,but its design usually involves great uncertainties that can lead to economic cost overruns in construction *** high dispersion in the properties of the improved material leads to designers assuming a conservative,arbitrary and unjustified strength,which is even sometimes subjected to the results of the test *** present paper presents an approach for prediction of the uniaxial compressive strength(UCS)of jet grouting columns based on the analysis of several machine learning algorithms on a database of 854 results mainly collected from different research *** selected machine learning model(extremely randomized trees)relates the soil type and various parameters of the technique to the value of the compressive *** the complex mechanism that surrounds the jet grouting process,evidenced by the high dispersion and low correlation of the variables studied,the trained model allows to optimally predict the values of compressive strength with a significant improvement with respect to the existing ***,this work proposes for the first time a reliable and easily applicable approach for estimation of the compressive strength of jet grouting columns.

关键词： Jet grouting Ground improvement Compressive strength Machine learning

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Single-cell transcriptome profiling of human HSCs during development:new insights into HSC ontogeny

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Signal Transduction and Targeted Therapy 2023年第3期8卷 877-878页

作者： edgar Grinstein Csaba Mahotka department of Hematology Oncology and Clinical ImmunologyMedical FacultyHeinrich Heine UniversityDüsseldorfGermany Institute of Pathology Medical FacultyHeinrich Heine UniversityDüsseldorfGermany

A study recently published in Nature reported a single-cell transcriptome map of human hematopoietic stem cells(HSCs)and a gene expression signature that distinguishes nascent HSCs from non-HSCs during prenatal development.1 This transcriptome map provides an important tool for further elucidation of human HSC ontogeny and could also serve as a guide for generation of transplantable HSCs ex vivo,1 to widen the therapeutic application of HSCs.

关键词： HSCs transcriptome hematopoietic

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Shortening filtrations

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Science China Mathematics 2012年第4期55卷 687-693页

作者： ENOCHS edgar E. department of Mathematics University of Kentucky

Let C be a set of modules. We argue that there is an ordinal d such that if a module has a filtration by modules in g, then it has a filtration of length k by direct sums of modules in C. As an application we give ano... 详细信息

关键词： Hill classes filtrations precovering

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Unveiling the time-temperature dependence of metastability of supercooled liquid using nano-calorimetry

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 119-127页

作者： Yijun ding Lijian Song Zheng Wang Ruiqi Yu Junqiang Wang Lina Hu Yuanzheng Yue edgar d.Zanotto Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong University Jinan 250061China Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201China Key Laboratory of Experimental Teratology Shandong University Jinan 250061 China department of Chemistry and Bioscience Aalborg UniversityAalborg 9220Denmark department of Materials Engineering Federal University of Sao CarlosSao Carlos SP 13.565-905Brazil

There is a lack of understanding of both the conversion of an unstable glass into a metastable supercooled liquid(MSL) upon heating and the metastability of MSLs. In this study, we investigated the time-and temperature-dependent metastability of an MSL using an advanced nano-calorimetric technique. The chosen Au-based metallic glass(Au MG) allowed adequate probing of its MSL in a temperature range between 10 and 70 K above the standard glass transition temperature. We found that the survival time of the MSL state is a quadratic function of temperature. Beyond this duration threshold, the sample undergoes fast crystallization even if it is below the crystallization temperature that is measured using differential scanning *** transmission electron microscopy, we observed the formation of clusters with a partially ordered lattice structure during relaxation in the Au MG sample fabricated using a nano-calorimeter. The atomic ordering within the clusters was enhanced by increasing time and temperature in the MSL region. Once the as-produced glass entered the MSL stage upon heating followed by a quenching stage at a given rate, the mechanical properties of the quenched glass remained the same regardless of its holding temperature and duration within the MSL region. This work provides insights into the glass-MSL-crystal transformation and offers guidance for designing standard metallic glasses for property characterizations.

关键词： metallic glass supercooled liquid relaxation nucleation nano calorimetric technology

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High resolution, binder-free investigation of the intrinsic activity of immobilized NiFe LdH nanoparticles on etched carbon nanoelectrodes

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Nano Research 2018年第11期11卷 6034-6044页

作者： Patrick Wilde Stefan Barwe Corina Andronescu Wolfgang Schuhmann edgar Ventosa Analytical Chemistry - Center for Electroche.mical Sciences (CES) Ruhr-Universitat Bochum Universitasstr. 150 D-44780 Bochum Germany IMdEA Energy Avda. Ramo de la Sagra 3 28935 Motoles Spain

The determination of the intrinsic properties of nanomaterials is essential for their optimization as electrocatalysts, however it poses great challenges from the standpoint of analytical tools and methods. Herein, we report a novel methodology that allows for a binder-free investigation of electrocatalyst nanoparticles. The potential-assisted immobilization of a non-noble metal catalyst, i.e., nickel-iron layered double hydroxide (NiFe LdH) nanoparticles, was employed to directly attach small nanoparticle ensembles from a suspension to the surface of etched carbon nanoelectrodes. The dimensions of this type of electrodes allowed for the immobilization of the catalyst material below the picogram scale and resulted in a high resolution towards the faradaic current response. In addition the effect of the electrochemical aging on the intrinsic activity of the catalyst was investigated in alkaline media by means of continuous cyclic voltammetry. A change in the material properties could be observed, which was accompanied by a substantial decrease in its intrinsic activity.

关键词： oxygen evolution reaction nickel-iron layered double hydroxide (NiFe LdH) immobilization nanoelectrocatalysis nanoelectrodes nanoimpacts

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Visual grading criteria for Japanese larch ( Larix kaempferi ) structural timber from Spain

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Journal of Forestry Research 2020年第6期31卷 2605-2614页

作者： Mari-Jose Barriola José-Ramón Aira edgar Lafuente Tknika LHri Aplikatutako Ikerketa eta Berrikuntzako EAEko zentroaZamalbide Auzoa z/g20100 ErrenteriaGipuzkoaSpain Escuela de Ingeniería de la Industria Forestal Agronómica y de la BioenergíaUniversidad de ValladolidUVa-Campus Duques de Sorias/n42005 SoriaSpain Cesefor Centro de Servicios y Promoción Forestal y de su Industria de Castilla y LeónCalle C42005 SoriaSpain

Larch wood is structurally classifi ed in many countries as one of conifers with the highest load-bearing capacity(strength class of C30).The Spanish visual classifi cation regulation only assigns a strength class to 4 pine woods:Laricio pine(Pinus nigra ***),Silvestre pine(Pinus sylvestris L.),Radiata pine(Pinus radiata ***),and Pinaster pine(Pinus pinaster Ait.).This work adds to the number of structurally characterised species by creating a visual classifi cation table for Japanese larch wood(Larix kaempferi(Lamb.)Carr.)which diff erentiates between 2 visual classes,MEG-1 and *** strength values were calculated for each class(fk,MEG-1=31.80 MPa,f k,MEG-2=24.55 MPa),mean module of elasticity(E 0,mean,MEG-1=13,082 MPA,E 0,mean,MEG-2=12,320 MPA)and density(ρk,MEG-1=456.6 kg m−3,ρk,MEG-2=469.1 kg m−3),before fi nally assigning a strength class of C30 to visual class MEG-1,and a strength class of C24 to visual class MEG-2.

关键词： Japanese larch wood Visual grading Strength class Mechanical properties density

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Growth and form of Quercus robur and Fraxinus excelsior respond distinctly different to initial growing space: results from 24-year-old Nelder experiments

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Journal of Forestry Research 2013年第1期24卷 1-14页

作者： Christian Kuehne Patrick Pyttel edgar Kublin Jürgen Bauhus Institute of Silviculture University of FreiburgD-79085 Freiburg i.Br.Germany. Faculty of Forests and Forestry University of Applied Sciences Wei- henstephan-TriesdorfHans-Carl-von-Carlowitz-Platz 3D-85354 FreisingGermany department of Biometry and Informatics Forest Research Station Baden-WürttembergPostfach 708D-79007 FreiburgGermany

Initial growing space is of critical importance to growth and quality development of individual trees. We investigated how mortality, growth （diameter at breast height, total height）, natural pruning （height to first dead and first live branch and branchiness） and stem and crown form of 24-year-old pedunculate oak （Quercus robur [L.]） and European ash （Fraxinus excelsior [L.]） were affected by initial spacing. data were recorded from two replicate single-species Nelder wheels located in southern Germany with eight initial stocking regimes varying from 1,020 to 30,780 seedlings·ha？1. Mortality substantially decreased with increasing initial growing space but significantly differed among the two species, averaging 59% and 15% for oak and ash plots, respectively. In contrast to oak, the low self-thinning rate found in the ash plots over the investigated study period resulted in a high number of smaller intermediate or suppressed trees, eventually retarding individual tree as well as overall stand development. As a result, oak gained greater stem dimensions throughout all initial spacing regimes and the average height of ash significantly increased with initial growing space. The survival of lower crown class ashes also appeared to accelerate self-pruning dynamics. In comparison to oak, we observed less dead and live primary branches as well as a smaller number of epicormic shoots along the first 6 m of the lower stem of dominant and co-dominant ashes in all spacing regimes. Whereas stem form of both species was hardly affected by initial growing space, the percentage of brushy crowns significantly increased with initial spacing in oak and ash. Our findings suggest that initial stockings of ca. 12,000 seedlings per hectare in oak and 2,500 seedlings per hectare in ash will guarantee a sufficient number of at least 300 potential crop trees per hectare in pure oak and ash plantations at the end of the self-thinning phase, respectively. If the problem of epicormic shoots a

关键词： spacing trial stocking self-thinning intraspecific competition qualification spatially explicit modelling generalized additive model

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How beneficial are relational capital and technology orientation for innovation?Evidence from Mexican SMEs

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International Journal of Innovation Studies 2022年第1期6卷 1-10页

作者： edgar R.Ramírez-Solis Joan Llonch-Andreu Alberto d.Malpica-Romero Tecnologico de Monterrey Departamento de Gestion y Liderazgo45201ZapopanJal.Mexico Universidad Autonoma de Barcelona Business Economics DepartmentFaculty of Economics08193BarcelonaSpain

Globally,small and medium-sized enterprises(SMEs)are engines of economic growth and job *** the pandemic,innovation activities have become more critical than ever as a generator of ***,we need to better understand the factors that lead to innovation in *** study aims to analyze the role of relational capital and technology orientation in innovation to appreciate its final impact on firm *** main results reveal a strong positive effect of relational capital on innovation,but the effect is not so strong as firm *** also found a strong positive effect of relational capital on technology ***,we offer some clues in the debate on technology as a source of innovation and how relational capital and technology orientation are related to a firm’s *** results reveal significant implications for innovation policies and relational capital strategies for SMEs.

关键词： Strategic orientation Technology orientation Relational capital Innovation SMEs

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