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Statistical analysis of physico-mechanical parameters of sandstones occurring in orogenic settings

Journal of Mountain Science 2024年第4期21卷 1388-1402页

作者： PAPPALARDO Giovanna CARBONe Serafina MONACO Carmelo ZOCCO Giordana MINeO Simone Dipartimento Di Scienze Biologiche Geologiche E AmbientaliUniversitàDegli Studi Di CataniaCorso Italia 5795129 CataniaItaly

In northeastern Sicily(Italy),sandstone rock masses widely crop out as cover deposits over crystalline terrains belonging to the orogenic *** being part of the same geological formation,these sandstones are characterized by highly different features in terms of texture and physico-mechanical *** poses a scientific question on the possibility of tracing these rocks to a single statistical model,which could be representative of their main engineering geological ***,it is worth investigating on the possible reasons of such differences,that should be searched either in the current geographical sandstone distribution or in the rock *** this study,sandstone samples were collected from different sites and were analyzed at both the hand and thin section *** sandstone types were recognized,characterized by a different ***,the laboratory characterization allowed estimating their main physico-mechanical and ultrasonic properties,such as porosity,density,mechanical strength,deformability,and ultrasonic *** rock mechanical strength proved linked to the rock compactness and to the presence of lithic fragments,while pores and a pseudo-matrix between grains represent weakening *** data were also statistically analyzed by grouping the specimens according to a geographical criterion,with respect to their sampling area,but no link was found between location and rock ***,with the aim of achieving mathematical laws that could be used to predict some rock properties from others,useful for practical purposes when dealing with such a high property variability,single and multiple regression analyses were carried *** show that the Uniaxial Compressive Strength,porosity,and P-wave velocity are the best predictors for a quick,indirect estimation of the main physico-mechanical *** methodological approach developed for this research can be taken as reference to study other world

关键词： Sandstone Laboratory test Uniaxial Compressive Strength Porosity Rocks

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Saffman–Taylor instability in eccentric cylinders at gaseous cavitation

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Friction 2024年第2期12卷 356-362页

作者： Anatoliy A.MONAKHOV Nikolay BUKHARIN Institute of Mechanics Moscow State UniversityMoscow 119899Russia ThermoFluid Solutions Ltd. CalgaryAlberta T3G4E8Canada

A flow of silicon fluid in the gap between eccentric cylinders was studied *** condition of gaseous cavitation inception during the rotation of internal cylinder was *** was shown that at reduction of the gap between cylinders Saffman–Taylor instability appeared on surface of the internal cylinder and then gaseous cavitation was *** of one uniform gas formation appearance under this type of instability was demonstrated.

关键词： gaseous cavitation Saffman-Taylor instability eccentric cylinders friction lubrication theory

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exploring the effects of dietary inulin in rainbow trout fed a high‑starch,100%plant‑based diet

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Journal of Animal Science and Biotechnology 2024年第2期15卷 713-732页

作者： Raphaël Defaix Jep Lokesh Laura Frohn Mickael Le Bechec Thierry Pigot Vincent Veron Anne Surget Sandra Biasutti Frederic Terrier Sandrine Skiba-Cassy Jerome Roy Stephane Panserat Karine Ricaud Universite de Pau et Des Pays de L’Adour E2S UPPAINRAENUMEASaint‑Pee‑Sur‑NivelleFrance Universite de Pau et Des Pays de L’Adour E2S UPPACNRSIMT Mines AlesIPREMPauFrance Universite de Pau et Des Pays de L’Adour E2S UPPAIUT des Pays de l’AdourDepartement Genie BiologiqueMont de MarsanFrance.

Background High dietary carbohydrates can spare protein in rainbow trout(Oncorhynchus mykiss)but may affect growth and ***,a prebiotic,could have nutritional and metabolic effects,along with anti-inflammatory properties in teleosts,improving growth and *** tested this hypothesis in rainbow trout by feeding them a 100%plant-based diet,which is a viable alternative to fishmeal and fish oil in aquaculture *** a two-factor design,we examined the impact of inulin(2%)as well as the variation in the carbohydrates(CHO)/plant protein ratio on rainbow *** assessed the influence of these factors on zootechnical parameters,plasma metabolites,gut microbiota,production of short-chain fatty acids and lactic acid,as well as the expression of free-fatty acid receptor genes in the mid-intestine,intermediary liver metabolism,and immune markers in a 12-week feeding *** The use of 2%inulin did not significantly change the fish intestinal microbiota,but interestingly,the high CHO/protein ratio group showed a change in intestinal microbiota and in particular the beta diversity,with 21 bacterial genera affected,including Ralstonia,Bacillus,and 11 lactic-acid producing *** were higher levels of butyric,and valeric acid in groups fed with high CHO/protein diet but not with *** high CHO/protein group showed a decrease in the expression of pro-inflammatory cytokines(il1b,il8,and tnfa)in liver and a lower expression of the genes coding for tight-junction proteins in mid-intestine(tjp1a and tjp3).However,the 2%inulin did not modify the expression of plasma immune ***,inulin induced a negative effect on rainbow trout growth performance irrespective of the dietary *** With a 100%plant-based diet,inclusion of high levels of carbohydrates could be a promising way for fish nutrition in aquaculture through a protein sparing effect whereas the supplementation of 2%inulin does not appear to improve the use of CHO wh

关键词： Aquaculture Fish nutrition Gut microbiota Immune markers Intermediary metabolism Inulin Prebiotic Rainbow trout Short-chain fatty acids

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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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Impact of the Brink-Axel hypothesis on unique first-forbiddenβ-transitions for r-process nuclei

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Chinese Physics C 2024年第3期48卷 148-168页

作者： Fakeha Farooq Jameel-Un Nabi Ramoona Shehzadi Department of Physics University of the PunjabQuaid-e-Azam Campus 54590LahorePakistan University of Wah Quaid AvenueWah Cantt 47040PunjabPakistan

Key nuclear inputs for the astrophysical r-process simulations are the weak interaction ***,the accuracy of these inputs directly affects the reliability of nucleosynthesis *** majority of the stellar rates,used in simulation studies are calculated by invoking the Brink-Axel(BA)*** BA hypothesis assumes that the strength functions of all parent excited states are the same as for the ground state,only shifted in ***,the BA hypothesis has to be tested against microscopically calculated state-by-state *** this project,we study the impact of the BA hypothesis on calculated stellarβ^(-)-decay and electron capture *** investigation include both unique first forbidden(U1F)and allowed transitions for 106 neutron-rich trans-iron nuclei([27,77]≤[Z,A]≤[82,208]).The calculations were performed using the deformed proton-neutron quasiparticle random-phase approximation(pn-QRPA)model with a simple plus quadrupole separable and schematic ***-point and several key r-process nuclei lie within the considered mass region of the nuclear *** computed electron capture andβ^(-)-decay rates using two different prescriptions for strength *** was based on invoking the BA hypothesis and the other was the state-by-state calculation of strength functions,under stellar density and temperature conditions([10,1]≤[ρYe(g/cm^(3)),T(GK)]≤[10^(11),30]).Our results show that the BA hypothesis invoked U1Fβ^(-)rates are overestimated by 4–5 orders of magnitude as compared to microscopic *** capture rates,more than two orders of magnitude differences were noted when applying the BA *** was concluded that the BA hypothesis is not a reliable approximation,especially forβ^(-)-decay forbidden transitions.

关键词： Brink-Axel hypothesis pn-QRPA model unique first forbiddenβ-transitions GT strength functions trans-iron nuclei r-process

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Review on the plastic instability of medium -Mn steels for identifying the formation mechanisms of Lüders and Portevin -Le Chatelier bands

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1285-1297页

作者： Bin Hu Han Sui Qinghua Wen Zheng Wang Alexander Gramlich Haiwen Luo School of Metallurgical and ecological engineering University of Science and Technology BeijingBeijing 100083China Steel Institute RWTH Aachen UniversityIntzestraße 152072 AachenGermany

Plastic instability,including both the discontinuous yielding and stress serrations,has been frequently observed during the tensile deformation of medium-Mn steels(MMnS)and has been intensively studied in recent ***,research results are controversial,and no consensus has been achieved regarding the ***,we first summarize all the possible factors that affect the yielding and flow stress serrations in MMnS,including the morphology and stability of austenite,the feature of the phase interface,and the deformation ***,we propose a universal mechanism to explain the conflicting experimental *** conclude that the discontinuous yielding can be attributed to the lack of mobile dislocation before deformation and the rapid dislocation multiplication at the beginning of plastic ***,the results show that the stress serrations are formed due to the pinning and depinning between dislocations and interstitial atoms in ***-induced martensitic transformation,influenced by the mechanical stability of austenite grain and deformation parameters,should not be the intrinsic cause of plastic ***,it can intensify or weaken the discontinuous yielding and the stress serrations by affecting the mobility and density of dislocations,as well as the interaction between the interstitial atoms and dislocations in austenite grains.

关键词： medium manganese steel discontinuous yielding stress serrations retained austenite dislocations

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Use of priming strategies to advance the clinical application of mesenchymal stromal/stem cell-based therapy

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World Journal of Stem Cells 2024年第1期16卷 7-18页

作者： Vitale Miceli Department of Research Istituto Mediterraneo per i Trapianti e Terapie ad alta SpecializzazionePalermo 90127Italy

Mesenchymal stromal/stem cells(MSCs)have garnered significant attention in the field of regenerative medicine due to their remarkable therapeutic *** play a pivotal role in maintaining tissue homeostasis and possess diverse functions in tissue repair and recovery in various *** cells are charac-terized by easy accessibility,few ethical concerns,and adaptability to in vitro cultures,making them a valuable resource for cell therapy in several clinical *** the years,it has been shown that the true therapeutic power of MSCs lies not in cell engraftment and replacement but in their ability to produce critical paracrine factors,including cytokines,growth factors,and exosomes(eXOs),which modulate the tissue microenvironment and facilitate repair and regeneration ***,MSC-derived products,such as condi-tioned media and eXOs,are now being extensively evaluated for their potential medical applications,offering advantages over the long-term use of whole ***,the efficacy of MSC-based treatments varies in clinical trials due to both intrinsic differences resulting from the choice of diverse cell sources and non-standardized production *** address these concerns and to enhance MSC therapeutic potential,researchers have explored many priming strategies,including exposure to inflammatory molecules,hypoxic conditions,and three-dimensional culture *** approaches have optimized MSC secretion of functional factors,empowering them with enhanced immunomodulatory,angiogenic,and regenerative properties tailored to specific medical *** fact,various priming strategies show promise in the treatment of numerous diseases,from immune-related disorders to acute injuries and ***,in order to exploit the full therapeutic potential of MSC therapy,the most important challenge is to optimize the modulation of MSCs to obtain adapted cell therapy for specific clinical *** other words,to unlock t

关键词： Mesenchymal stromal/stem cells Therapeutic properties Paracrine effects Cell priming Cell-free therapies Regenerative medicine

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Use of infrared thermography to detect reactions to stressful events:does animal personality matter?

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Integrative Zoology 2024年第2期19卷 224-239页

作者： Maria Vittoria MAZZAMUTO Marina MORANDINI William LAMPMAN Lucas Armand WAUTeRS Damiano PReATONI John Lad KOPROWSKI Adriano MARTINOLI School of Natural Resources and environment College of Agriculture and Life ScienceUniversity of ArizonaArizonaUSA Unitàdi Analisi e Gestione delle Risorse Ambientali Dipartimento di Scienze Teoriche e ApplicateGuido Tosi Research GroupUniversitàdegli Studi dell’InsubriaVareseItaly Haub School of environment and Natural Resources University of WyomingWyomingUSA

The study of the relationship between animal stress and personality for free-ranging animals is limited and provides contrasting *** perception of stressors by an individual may vary due to its personality,and certain personality traits may help individuals to better cope with *** non-invasive infrared thermography(IRT),we investigated the link between physiological and behavioral components expressed during an acute stress event by free-ranging Fremont’s squirrels(Tamiasciurus fremonti).We expected that,during the acute stress event of being approached by the researcher,individuals that showed a fast pace-of-life syndrome(bolder,more active,and less social/more aggressive)based on an arena test would exhibit stronger sympathetic-adrenal-medullary system reactivity showing a more intense stress-induced hyperthermia(high core body temperature and low peripheral temperature)than individuals with a slow pace of life(shy,less active,and more social).We successfully employed IRT technology to images of Fremont’s squirrels with identification of the individuals’body parts(eye,nose,ear,hind foot).However,we found no support for our ***’body surface temperatures told us more about a squirrel’s external environment and less about the thermal state of the body in that environment following a stressful *** studies need to assess how to make IRT effective and efficient in the field and improve its performance in studying the relationships between physiology and personality in wildlife.

关键词： non-invasive method open field test physiology stress-induced hyperthermia Tamiasciurus fremonti

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Recent progress in carbonaceous materials based Z-scheme and Sscheme heterojunctions for photocatalytic clean energy generation

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新型炭材料(中英文) 2024年

作者： Sahil Rana Amit Kumar Wang Tong-tong Gaurav Sharma Pooja Dhiman Alberto García-Penas Interdisciplinary and Innovate Research Xi'an University of Architecture and Technology Departamento de Ciencia e Ingeniería de Materiales e Ingeniería Química (IAAB) Universidad Carlos III de Madrid International Research Centre of Nanotechnology for Himalayan Sustainability (IRCNHS) Shoolini University

Carbonaceous materials including carbon nanotubes/nanofibers, graphene, graphene oxide, reduced graphene oxide,graphyne, graphdiyne, carbon quantum dots and fullerenes have gained considerable attention in the recent years for their unique properties such as high conductivity, excellent stability and biocompatibility. The integration of these carbonaceous materials into Zscheme and S-scheme heterojunctions has emerged as a transformative strategy to enhance the photocatalytic efficiency for energy conversion applications. This review delves into the fundamental principles of clean energy generation such as photocatalytic H2generation and CO2reduction, elucidating their respective mechanisms and advantages. Furthermore, various types of carbonaceous materials, their synthesis and construction of Z-scheme and S-scheme heterojunctions are discussed emphasizing their role in promoting charge separation, reducing recombination losses and extending the spectral response range. With the focus on solar fuel production,the recent advancements in carbonaceous based Z-scheme and S-scheme heterojunctions are discussed and summarized for photocatalytic H2generation and CO2reduction. Lastly, the current bottlenecks and challenges in the field of carbonaceous based photocatalysts are discussed with the valuable insights for future development in this particular field.

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Dielectric and physico-chemical behavior of single thermally thick wood blocks under microwave assisted pyrolysis

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Particuology 2024年第3期86卷 291-303页

作者： Nicole Vorhauer-Huget Jakob Seidenbecher Supriya Bhaskaran Francesca Schenkel Lucas Briest Suresh Gopalkrishna Jan Barowski Andrea Dernbecher Liane Hilfert Ilona Rolfes Alba Dieguez-Alonso Otto von Guericke University Magdeburg Universitatsplatz 239106MagdeburgGermany Ruhr University Bochum Institute of Microwave SystemsUniversitatsstraβe 15044801BochumGermany

Pyrolysis of thermally thick beech wood blocks with a size of around 2.5×8×6 cm^(3)(width×length×height)was carried out in a lab scale microwave reactor with a frequency of 2.45 GHz,operated,both,at 300 W and 600 W under inert conditions,using N_(2) at around 400 mbar absolute *** microwave cavity had a size of 20×20×20 cm^(3).The specific energy supply referred to the untreated wood block was 4-8 W/g,with slight variations depending on the initial water *** mass loss and the reflected microwave power were in-situ monitored during the *** sample surface and chamber temperatures were measured with a pyrometer and a thermocouple,***-chemical and dielectric properties of the produced solids were investigated and compared to those of chars produced under conventional pyrolysis using the same raw *** is shown that the complex dielectric permittivity of the solid products changed drastically during the pyrolysis process,with increasing heating properties as the conversion process *** was easily achieved using 60o W without ***,300 W was not enough to achieve a high conversion degree,independently of the irradiation ***,together with the physico-chemical analyses of the solids,hinted to the importance of the transport kinetics in thermally thick materials,although further investigationis still required.

关键词： Microwave assistedpyrolysis Conventional pyrolysis Dielectric measurements Penetration depth elemental analysis

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