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Numerical modeling of time-dependent deformation and induced stresses in concrete pipes constructed in Queenston shale using micro-tunneling technique

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第2期10卷 290-309页

作者： Hayder Mohammed Salim Al-Maamori M.Hesham El Naggar silvana micic Department of Civil and Environmental Engineering Western University Geotechnical Research Center Western University

Effects of time-dependent deformation（TDD） on a tunnel constructed using the micro-tunneling technique in Queenston shale（QS） are investigated employing the finite element method. The TDD and strength parameters of the QS were measured from tests conducted on QS specimens soaked in water and lubricant fluids（LFs） used in micro-tunneling such as bentonite and polymer solutions. The numerical model was verified using the results of TDD tests performed on QS samples, field measurements of some documented projects, and the closed-form solutions to circular tunnels in swelling rock. The verified model was then employed to conduct a parametric study considering important micro-tunneling design parameters, such as depth and diameter of the tunnel, in situ stress ratio（K;）, and the time lapse prior to replacing LFs with permanent cement grout around the tunnel. It was revealed that the time lapse plays a vital role in controlling deformations and associated stresses developed in the tunnel *** critical case of a pipe or tunnel in which the maximum tensile stress develops at its springline occurs when it is constructed at shallow depths in the QS layer. The results of the parametric study were used to suggest recommendations for the construction of tunnels in QS employing micro-tunneling.

关键词： Numerical model Micro-tunneling Queenston shale(QS) Lubricant fluids(LFs)

A Compilation of the Geo-Mechanical Properties of Rocks in Southern Ontario and the Neighbouring Regions

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Open Journal of Geology 2014年第5期4卷 210-227页

作者： Hayder Mohammed Salim Al-Maamori Mohamed Hesham El Naggar silvana micic Department of Civil and Environmental Engineering Western University London Canada

The available measurements of the geo-mechanical properties of rocks in Southern Ontario and the neighbouring regions (New York, Ohio, Michigan, Indiana, Illinois, Wisconsin, and Minnesota) are summarized and presented. These measurements were compiled from available published data in the relevant literature and also from data that were collected from major underground projects in these regions. The compiled data are presented in three categories: measured in-situ stresses in different rock formations;calculated strength, stiffness and deformation including time-dependent deformation properties;and the measured dynamic properties of intact rock specimens from different rock formations in Southern Ontario and the neighbouring regions. The data presented in this paper can be used as a resource for preliminary evaluation of the geomechanical properties of the rocks in these regions. The presented geo-mechanical properties were generally obtained from in-situ measurements and from laboratory tests that were conducted on intact rock specimens from freshly excavated rock samples. Moreover, the time-dependent deformation properties of rocks in these regions were obtained from laboratory tests that were performed on intact rock specimens submerged in water. However, the influence of drilling fluids such as bentonite slurry and synthetic polymers solution, on the geo-mechanical properties of rocks is not evident and needs to be investigated.

关键词： Geo-Mechanical Properties Rocks Southern Ontario Compilation

Palm oil biodiesel:An assessment of PAH emissions,oxidative potential and ecotoxicity of particulate matter

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Journal of Environmental Sciences 2021年第3期33卷 326-338页

作者： silvana Arias Francisco Molina John R.Agudelo Grupo de Investigación en Gestión y Modelación Ambiental-GAIA Escuela AmbientalFacultad de IngenieríaUniversidad de Antioquia UdeACalle 70 No.52-21MedellínColombia Departamento de Ingeniería Mecánica Universidad de Antioquia UdeA

This work assessed the impact of fuelling an automotive engine with palm biodiesel(pure,and two blends of 10%and 20%with diesel,B100,B10 and B20,respectively)operating under representative urban driving conditions on 17 priority polycyclic aromatic hydrocarbon(PAH)compounds,oxidative potential of ascorbic acid(OP^(AA)),and ecotoxicity through D aphnia pulex mortality *** diluted with filtered fresh air(WD)gathered in a minitunel,and particulate matter(PM)collected directly from the exhaust gas stream(W/oD)were used for *** showed that PM collecting method significantly impact PAH *** all PAH appeared in both,WD and W/oD,higher concentrations were obtained in the last *** biodiesel concentration in the fuel blend decreased all PAH compounds,and those with 3 and 5 aromatic rings were the most *** biodiesel affected both OP^(AA)and *** B10 and B20 exhibited the same rate of ascorbic acid(AA)depletion,B100 showed significant faster oxidation rate during the first four minutes and oxidized 10%more AA at the end of the test.B100 and B20 were significantly more ecotoxic than *** lethal concentration LC50 for B10 was 6.13 mg/*** was concluded that palm biodiesel decreased PAH compounds,but increased the oxidative potential and ecotoxicity.

关键词： Biodiesel Particulate matter P emissions Oxidative stress Ecotoxicity Daphnia pulex

New neuroprotective perspectives in fighting oxidative stress and improving cellular energy metabolism by oleocanthal

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Neural Regeneration Research 2019年第7期14卷 1217-1218页

作者： Cristina Angeloni Laura Giusti silvana Hrelia School of Pharmacy University of Camerino Department of Clinical and Experimental Medicine University of Pisa Department for Life Quality Studies Alma Mater Studiorum-University of Bologna

Neurodegenerative diseases are a heterogeneous group of disorders characterized by a progressive dysfunction and death of neural cells which lead to compromised motor or cognitive ***,the loss of neuron is associated with both gliosis and,frequently,with abnormal accumulation of extracellular and intracellular filamentous deposit in specific cell *** a rapidly increasing aging population,these diseases are becoming a primary health problem(Albers and Beal,2000).

关键词： New neuroprotective fighting oxidative

Predicting stable crystalline compounds using chemical similarity

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npj Computational Materials 2021年第1期7卷 99-107页

作者： Hai-Chen Wang silvana Botti Miguel A.L.Marques Institut für Physik Martin-Luther-Universität Halle-Wittenberg06120 Halle(Saale)Germany Institut für Festkörpertheorie und-Optik Friedrich-Schiller-Universität Jena and European Theoretical Spectroscopy FacilityMax-Wien-Platz 107743 JenaGermany

We propose an efficient high-throughput scheme for the discovery of stable crystalline *** approach is based on the transmutation of known compounds,through the substitution of atoms in the crystal structure with chemically similar *** concept of similarity is defined quantitatively using a measure of chemical replaceability,extracted by data-mining experimental *** this way we build 189,981 possible crystal phases,including 18,479 that are on the convex hull of *** resulting success rate of 9.72%is at least one order of magnitude better than the usual success rate of systematic high-throughput calculations for a specific family of materials,and comparable with speed-up factors of machine learning filtering *** a characterization of the set of 18,479 stable compounds,we calculate their electronic band gaps,magnetic moments,and *** approach,that can be used as a filter on top of any high-throughput scheme,enables us to efficiently extract stable compounds from tremendously large initial sets,without any initial assumption on their crystal structures or chemical compositions.

关键词： stability similarity crystalline

Synthesis of Water-soluble, Polyester-based Dendrimer Prodrugs for Exploiting Therapeutic Properties of Two Triterpenoid Acids

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Chinese Journal of Polymer Science 2018年第9期36卷 999-999,1000-1010页

作者： silvana Alfei Gaby Brice Taptue Silvia Catena Angela Bisio Dipartimento di Farmacia Sezione di Chimica e Tecnologie Farmaceutiche e Alimentari Università di Genova

Dendrimers are macromolecules characterized by high controlled size, shape and architecture, presence of inner cavities able to accommodate small molecules and many peripheral functional groups to bind target entities. They are of eminent interest for biomedical applications, including gene transfection, tissue engineering, imaging, and drug delivery. The well-known pharmacological activities of ursolic and oleanolic acids are limited by their small water solubility, non-specific cell distribution, low bioavailability, poor pharmacokinetics, and their direct administration could result in the release of thrombi. To overcome such problems, in this paper we described their physical incorporation inside amino acids-modified polyester-based dendrimers which made them highly water-soluble. IR, NMR, zeta potential, mean size of particles, buffer capacity and drug release profiles of prepared materials were reported. The achieved water-soluble complexes harmonize a polycationic character and a buffer capacity which presuppose efficient cell penetration and increased residence time with a biodegradable cell respectful scaffold, thus appearing as a promising team of not toxic prodrugs for safe administration of ursolic and oleanolic acids.

关键词： Polyester-based amino acids-modified dendrimers Physical encapsulation Water-soluble dendriplexes Buffer capacity NMR investigations

Biosolid Application to Agricultural Land a Contribution to Global Phosphorus Recycle： A Review

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Pedosphere 2017年第1期27卷 1-16页

作者： silvana Irene TORRI Rodrigo Studart CORRt Giancarlo RENELLA Department of Natural Resources and Environment School of Agriculture University of Buenos Aires Avenue San Martin 4453 Buenos Aires 1417 DSE (Argentina) University of Brasilia-UnB/PPGCA Campus Darcy Ribeiro Caixa Postal 04401 70910-970 DF (Brazil) Department of Agrifood Production and Environmental Sciences University of Florence Piazzale delle Caseine 18 Florence 50144 (Italy)

Phosphorus(P) is an essential nutrient required for plant *** population growth and rising global demand for food are expected to increase the demand for phosphate ***,high-quality phosphate rock reserves are progressively becoming *** of the increased pressure on P resources could be alleviated by recycling P present in ***,it is crucial to understand the dynamics of P in biosolid-amended soils,the effects of residual biosolid-borne P in soils,the way in which microorganisms may control P dynamics in biosolid-amended soils and the environmental implications of the use of biosolids as a source of *** research is needed to maximize biosolid-borne P uptake by crops and minimize its loss from biosolid-amended *** analysis of the microbiological control of P dynamics in biosolid-amended soils indicates interactions of biosolid P with other nutrients such as carbon(C) and nitrogen(N),suggesting that harmonization of the current regulation on the use of biosolids in agriculture,mainly based on total N and pollutant contents,is needed to better recycle P in agriculture.

关键词： anthropogenic P phosphate P availability P biogeocycle P uptake runoff P

Axillary lymph node management in breast cancer with positive sentinel lymph node biopsy

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World Journal of Clinical Oncology 2015年第1期6卷 1-6页

作者： Ioannis A Voutsadakis silvana Spadafora Division of Medical Oncology Department of Internal Medicine Sault Area Hospital Sault Ste. Marie Ontario ON P6B 0A8 Canada Division of Clinical Sciences Northern Ontario School of Medicine Sudbury Ontario ON P0M Canada

The surgical treatment of localized breast cancer has become progressively less aggressive over the *** management of the axillary lymph nodes has been modified by the introduction of sentinel lymph node biopsy. Axillary dissection can be avoided in patients with sentinel lymph node negative biopsies. Based on randomized trials data, it has been proposed that no lymph node dissection should be carried out even in certain patients with sentinel lymph node positive biopsies. This commentary discusses the basis of such recommendations and cautions against a general omission of lymph node dissection in breast cancer patients with positive sentinel lymph node biopsies. Instead, an individualized approach based on axillary tumor burden and biology of the cancer should be considered.

关键词： Tumor sub-types Micro-metastatic Node positive Breast cancer Axillary lymph node dissection Macro-metastatic Axillary recurrence

Resource management at the network edge for federated learning

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Digital Communications and Networks 2024年第3期10卷 765-782页

作者： silvana Trindade Luiz F.Bittencourt Nelson L.S.da Fonseca Institute of Computing State University of CampinasCampinasBrazil

Federated learning has been explored as a promising solution for training machine learning models at the network edge,without sharing private user *** limited resources at the edge,new solutions must be developed to leverage the software and hardware resources as the existing solutions did not focus on resource management for network edge,specially for federated *** this paper,we describe the recent work on resource manage-ment at the edge and explore the challenges and future directions to allow the execution of federated learning at the *** such as the discovery of resources,deployment,load balancing,migration,and energy effi-ciency are discussed in the paper.

关键词： Resource management Edge computing Federated learning Machine learning