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Effect of rhenium on the microstructure and mechanical behavior of Fe–2.25Cr–1.6W–0.25V-0.1C bainitic steels

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Journal of Materials Science & Technology 2017年第12期33卷 1487-1493页

作者： josé antonio Jiménez Manuel Carsí Oscar antonio Ruano Department of Physical Metallurgy Centro Nacional de lnvestigaciones MetalurgicasC.S.I.CAvda.Gregorio del Amo 828040 MadridSpain

A new ferritic creep resistant steel has been developed by eliminating Nb and adding 1.5 mass % Re to a ferritic steel grade T/P23 with the aim of enhancing its mechanical properties at high *** ingots of both steels, new grade and ASTM T/P 23, were hot rolled at 900℃ and then submitted to a thermal treatment consisting of solubilization at 1050℃ and tempering at 700℃. Tempered bainitic microstructures obtained contain second phases reinforcing carbide particles, mainly M_6C and M_（23）C_6 at the boundaries of both, prior austenite grains and bainitic ferrite laths, as well as MC within the grains. Mechanical properties at temperatures ranging from 540 to 600℃ were studied by strain-ratechange tests in compression at strain rates between 10^（-7） and 10^（-4）s^（-1）. These tests showed high stress exponents（n ≥ 20） and activation energies（Q ≈ 400 k J/mol） for both alloys, which were associated with a dislocation movement mechanism with a strong interaction between dislocations and precipitates. On the other hand, a creep exponent of 5 was derived for the stress dependence of minimum creep rate from conventional-type creep tests at 600℃. Although this stress exponent is usually related to a dislocation climb controlled creep mechanism, remarkable microstructural degradation observed with increasing creep time makes difficult to elucidate the true deformation mechanism controlling creep.

关键词： Creep resistant steel T/P23 Thermal treatment Tempered bainite High temperature mechanical properties Creep

Performance of statistical and machine learning-based methods for predicting biogeographical patterns of fungal productivity in forest ecosystems

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Forest Ecosystems 2021年第2期8卷 278-291页

作者： Albert Morera Juan Martínez de Aragón josé antonio Bonet Jingjing Liang Sergio de-Miguel Department of Crop and Forest Sciences University of LleidaAv.Alcalde Rovira Roure 191E-25198 LleidaSpain Joint Research Unit CTFC-AGROTECNIO-CERCA Center Av.Rovira Roure 19125198 LleidaSpain Forest Science and Technology Centre of Catalonia Ctra.Sant Llorençde Morunys km 225280 SolsonaSpain Forest Advanced Computing and Artificial Intelligence Laboratory Department of Forestry and Natural ResourcesPurdue UniversityWest LafayetteIN 47907USA

Background:The prediction of biogeographical patterns from a large number of driving factors with complex interactions,correlations and non-linear dependences require advanced analytical methods and modeling *** study compares different statistical and machine learning-based models for predicting fungal productivity biogeographical patterns as a case study for the thorough assessment of the performance of alternative modeling approaches to provide accurate and ecologically-consistent ***:We evaluated and compared the performance of two statistical modeling techniques,namely,generalized linear mixed models and geographically weighted regression,and four techniques based on different machine learning algorithms,namely,random forest,extreme gradient boosting,support vector machine and artificial neural network to predict fungal *** evaluation was conducted using a systematic methodology combining random,spatial and environmental blocking together with the assessment of the ecological consistency of spatially-explicit model predictions according to scientific ***:Fungal productivity predictions were sensitive to the modeling approach and the number of predictors ***,the importance assigned to different predictors varied between machine learning modeling *** tree-based models increased prediction accuracy by more than 10%compared to other machine learning approaches,and by more than 20%compared to statistical models,and resulted in higher ecological consistence of the predicted biogeographical patterns of fungal ***:Decision tree-based models were the best approach for prediction both in sampling-like environments as well as in extrapolation beyond the spatial and climatic range of the modeling *** this study,we show that proper variable selection is crucial to create robust models for extrapolation in biophysically differentiated *** allows for reducing the dime

关键词： Modeling Regression Biogeography Climate Forest Fungi Mushrooms

Visual function,performance,and processing of basketball players *** individuals

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Journal of Sport and Health Science 2020年第6期9卷 587-594页

作者： Jesús Vera Raimundo Jiménez David Cárdenas Beatriz Redondo josé antonio García Department of Optics Faculty of ScienceUniversity of GranadaGranada 18071Spain Department of Physical Education and Sport Faculty of Sport ScienceUniversity of GranadaGranada 18071Spain Sport and Health University Mixed Institute University of GranadaGranada 18071Spain

Background:Athletes tend to have better visuo-motor performance than do sedentary ***,several basic visual-function and perceptual parameters remain unexplored to *** this study,we investigated whether differences exist in visual function,performance,and processing between basketball players and individuals without a sport-involvement ***:A total of 33 healthy men with no visual impairment or pathology were divided into 2 groups,depending on the involvement in sport(semi-professional basketball players and sedentary individuals).We tested their baseline heart-rate variability in the resting position apart from subjective questionnaires to determine their physical fitness level,and we checked their visual function,performance,and processing through an extended battery of optometric ***:The 2 groups differed in resting heart-rate variability parameters(p<0.001),confirming their dissimilarities in regular time practising sports per *** basketball players showed a closer breakpoint and recovery nearpoint of convergence,a higher fusional-vergence rate,better discriminability halos,and better eye-hand coordination(all p values<0.05).Conclusion:These results show evidence that athletes,basketball players in this case,exhibit better performance in several visual abilities in comparison to a group of individuals without sporting backgrounds,suggesting an improvement due to the systematic involvement of those skills during basketball practice.

关键词： Exercise Fitness level Health Heart rate variability Visual skills Team sport

A Proof of Wedderburn＇s Theorem

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Algebra Colloquium 2015年第4期22卷 603-606页

作者： josé antonio Cuenca Mira Departamento de álgebra Geometría y Topología Facultad de Ciencias Universidad de Málaga 29071 Málaga Spain

In this note we first introduce the finite weak Herstein condition, which is a property that holds for every finite field. For a field F satisfying the finite weak Herstein condition, we then characterize whether all the finite-dimensional division F-algebras are commutative. This gives an alternate proof of Wedderburn＇s Theorem.

关键词： division algebra finite-dimensional algebra finite field Galois extension

Gravitational waves from compact objects

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Research in Astronomy and Astrophysics 2010年第11期10卷 1071-1099页

作者： josé antonio de Freitas Pacheco University of Nice-Sophia Antipolis Observatoire de la Cote d'Azur Laboratoire Cassiopée-UMR 6202 BP 4229-F606304-Nice Cedex 4-France

Large ground-based laser beam interferometers are presently in operation both in the USA （LIGO） and in Europe （VIRGO） and potential sources that might be detected by these instruments are revisited. The present generation of detectors does not have a sensitivity high enough to probe a significant volume of the universe and, consequently, predicted event rates are very low. The planned advanced generation of interferometers will probably be able to detect, for the first time, a gravitational sig- nal. Advanced LIGO and EGO instruments are expected to detect few （some）： binary coalescences consisting of either two neutron stars, two black holes or a neutron star and a black hole. In space, the sensitivity of the planned LISA spacecraft constellation will allow the detection of the gravitational signals, even within a ＂pessimistic＂ range of possible signals, produced during the capture of compact objects by supermassive black holes, at a rate of a few tens per year.

关键词： gravitational waves -- neutron stars -- black holes

There is life after coking for Ir nanocatalyst superlattices

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Nano Research 2022年第8期15卷 6969-6976页

作者： antonio J.Martínez-Galera Haojie Guo Mariano D.Jiménez-Sánchez Stefano Franchi Kevin C.Prince josé M.Gómez-Rodríguez Departamento de Física de la Materia Condensada Universidad Autónoma de MadridMadrid E-28049Spain Instituto Nicolás Cabrera Universidad Autónoma de MadridMadrid E-28049Spain Elettra-Sincrotrone Trieste S.C.p.A. in Area Science ParkBasovizza(Trieste)34149Italy Condensed Matter Physics Center(IFIMAC) Universidad Autónoma de MadridMadrid E-28049Spain

Achieving superior performance of nanoparticle systems is one of the biggest challenges in *** major phenomena,occurring during the reactions,hinder the development of the full potential of nanoparticle catalysts:sintering and contamination with carbon containing species,sometimes called ***,we demonstrate that Ir nanocrystals,arranged into periodic networks on hexagonal boron nitride(h-BN)supports,can be restored without sintering after contamination by persistent *** restoration yields the complete removal of carbon from the nanocrystals,which keep their crystalline structure,allowing operation without *** findings,together with the possibility of fine tuning the nanocrystals size,confer this nanoparticle system a great potential as a testbed to extract key information about catalysis-mediated oxidation *** the case of the CO oxidation by O2,reaction of interest in environmental science and green energy production,the existence of chemical processes not observed before in other nanoparticle systems is demonstrated.

关键词： catalysis coke nanoparticles scanning tunneling microscopy(STM) X-ray photoemission spectroscopy(XPS)

Evaluation of the effectiveness of horizontal subsurface flow constructed wetlands for different media

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Journal of Environmental Sciences 2010年第6期22卷 820-825页

作者： antonio Albuquerque josé Oliveira Sabrina Semitela Leonor Amaral Department of Civil Engineering and Architecture and C-MADE University of Beira Interior Municipality of Penamacor Department of Sciences and Environmental Engineering Faculty of Sciences and TechnologyNew University of Lisbon

Two media bed （gravel and Filtralite NR） were tested in a mesocosm to evaluate the removal of organic matter （as chemical oxygen demand （COD））, ammonia （NH4-N）, nitrite, nitrate and solid matter （as total suspended solids （TSS）） for a synthetic wastewater （acetate-based） and a domestic wastewater. The use of Filtralite allowed average removal rates （6--16.8 g COD/（m^2·day）, 0.8-1.1 g NH4-N/（m^2·day） and 3.1 g TSS/（m^2·day）） and removal efficiencies （65%-93%, 57%-85% and 78% for COD, NH4-N and TSS, respectively）, higher than that observed in the experiments with gravel. The applied loads of COD, ammonia, nitrate and TSS seem to influence the respective removal rates but only for the treatment of domestic wastewater with nigher correlation coefficients for Filtralite. Regardless the type of media bed and the type of wastewater, nitrate was completely removed for nitrogen loading rates up to 1.3 g NO3-N/（m^2·day）. There was no evidence of the influence of nitrate loads on the removal of organic matter.

关键词： media bed constructed wetlands pollutants removal rates

MMALE—A Methodology for Malware Analysis in Linux Environments

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Computers, Materials & Continua 2021年第5期67卷 1447-1469页

作者： joséJavier de Vicente Mohino Javier Bermejo Higuera Juan Ramón Bermejo Higuera Juan antonio Sicilia Montalvo Manuel Sánchez Rubio joséJavier Martínez Herraiz Escuela Superior de Ingeniería y Tecnología Universidad Internacional de La RiojaLogroño26006La RiojaSpain Departamento de Ciencias de la Computación de la Escuela Politécnica Superior Universidad de Alcaláde HenaresAlcaláde HenaresMadridSpain

In a computer environment,an operating system is prone to malware,and even the Linux operating system is not an *** recent years,malware has evolved,and attackers have become more qualified compared to a few years ***,Linux-based systems have become more attractive to cybercriminals because of the increasing use of the Linux operating system in web servers and Internet of Things(IoT)*** is the most employed OS,so most of the research efforts have been focused on its malware protection rather than on other operating *** a result,hundreds of research articles,documents,and methodologies dedicated to malware analysis have been ***,there has not been much literature concerning Linux security and protection from *** address all these new challenges,it is necessary to develop a methodology that can standardize the required steps to perform the malware analysis in depth.A systematic analysis process makes the difference between good and ordinary malware ***,a deep malware comprehension can yield a faster and much more efficient malware *** order to address all mentioned challenges,this article proposed a methodology for malware analysis in the Linux operating system,which is a traditionally overlooked field compared to the other operating *** proposed methodology is tested by a specific Linux malware,and the obtained test results have high effectiveness in malware detection.

关键词： Malware analysis methodology analysis Linux malware IoT malware

T-cell allorecognition of donor glutathione S-transferase T1 in plasma cell-rich rejection

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World Journal of Hepatology 2017年第27期9卷 1115-1124页

作者： María josé Martínez-Bravo Berta Sánchez josé Manuel Sousa María josé Acevedo Miguel Angel Gómez-Bravo antonio Núnez-Roldán Isabel Aguilera Immunology Service Instituto de Biomedicina de Sevilla Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla Digestive Diseases Service Hospital Universitario Virgen del Rocío Liver Transplant Unit Hospital Universitario Virgen del Rocío

AIM To investigate the role of glutathione S-transferase T1 donor-specific T lymphocytes in plasma cell-rich rejection of liver *** The study group included 22 liver transplant patients. Among them, 18 patients were mismatched for the glutathione S-transferase T1(GSTT1) alleles(don+/rec-), and 4 were matched(don+/rec+). Seven of the mismatched patients produced anti-GSTT1 antibodies and developed plasma cell-rich rejection(former de novo immune hepatitis). For the detection of specific Tlymphocytes, peripheral blood mononuclear cells were collected and stored in liquid nitrogen. The memory T cell response was studied by adding to the cell cultures to a mix of 39 custom-made, 15-mer overlapping peptides, which covered the entire GSTT1 amino acid sequence. The specific cellular response to peptides was analyzed by flow cytometry using the markers CD8, CD4, IL-4 and IFNγ.RESULTS Activation of CD8^+ T cells with different peptides was observed exclusively in the group of patients with plasma-cell rich rejection(3 out of 7), with production of IL-4 and/or IFNγ at a rate of 1%-4.92% depending on the peptides. The CD4^+ response was most common and not exclusive for patients with the disease, where 5 out of 7 showed percentages of activated cells from 1.24% to 31.34%. Additionally, two patients without the disease but with the mismatch had cells that became stimulated with some peptides(1.45%-5.18%). Highly unexpected was the finding of a double positive CD4^+CD8^(low) T cell population that showed the highest degree of activation with some of the peptides in 7 patients with the mismatch, in 4 patients with plasma cell-rich rejection and in 3 patients without the disease. Unfortunately, CD4^+CD8^(low) cells represent 1% of the total number of lymphocytes, and stimulation could not be analyzed in 9 patients due to the low number of gated cells. Cells from the 4 patients included as controls did not show activation with any of the peptides. CONCLUSION Patients

关键词： Donor-specific glutathione S-transferase T1 antibodies Indirect presentation Glutathione S-transferase T1-memory T cells De novo immune hepatitis Donor/recipient mismatch