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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

Sex-dependent resilience to extreme drought events: implications for climate change adaptation of a South American endangered tree species

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Ecological Processes 2024年第02期13卷 48-60页

作者： Sergio Piraino Martín ariel Hadad Yanina Antonia Ribas-Fernández Fidel Alejandro Roig Laboratorio de Dendrocronología e Historia Ambiental (IANIGLA CONICET ) Facultad de Ciencias Agrarias Universidad Nacional de Cuyo Laboratorio de Dendrocronología de Zonas áridas (CIGEOBIO CONICET ) Gabinete de Geología Ambiental (INGEO UNSJ) Hémera Centro de Observación de la Tierra Facultad de Ciencias Universidad Mayor

Background Recent changes in climatic trends are resulting in an increased frequency and intensity of extreme events, with unknown effect on ecosystem dynamics in the near future. Extreme drought episodes are recognized as disturbance factors capable of modifying forest dynamics and tree growth. Within this context, dioecious tree species may be impacted by climatic extremes, affecting male/female proportions and, consequently, reproductive processes and species persistence. Therefore, there is an urgent need for species-specific assessments of growth tolerance to extreme dry spells in dioecious tree species, to establish effective conservation strategies for these particular natural resources. Araucaria araucana(araucaria), an endangered dioecious Patagonian tree species, has recently undergone decay and mortality episodes in response to increasing dry climatic conditions. While sex-dependent tolerance to extreme drought episodes has been assessed in the species' humid distribution range, there is still a lack of information on the gender-based resilience of trees growing in the drier environments of the species' *** We reconstructed, through dendrochronological methods, the sex-dependent response of 105 araucaria individuals(55 female and 50 male trees) to five regional extreme dry spells employing a set of different indices. Resistance, recovery period, and average growth reduction of standardized tree-ring growth were examined, analysing the effect of biotic(sex, pre-drought stem tree growth) and abiotic(local climatic conditions before, during, and after extreme climatic episodes) factors on tree *** Sex influences only the species resistance to climatic disturbance, with male individuals showing lower tolerance to extreme drought events. Pre-drought radial growth rates and local meteorological conditions preceding, during, and following extreme dry spells strongly modulated araucaria radial growth resilience regardless of tree s

关键词： Araucaria Climate change Dendrochronology Extreme drought event Resilience

DEM analysis of the influence of stirrer design on die filling with forced powder feeding

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Particuology 2024年第5期88卷 107-115页

作者： Chao Zheng Edward Yost ariel R.Muliadi Nicolin Govender Ling Zhang Chuan-Yu Wu School of Chemistry and Chemical Engineering University of SurreyGuildfordGU2 7XHUnited Kingdom Small Molecule Pharmaceutics GenentechInc.One DNA WaySouth San FranciscoCA94080USA

Die filling is a critical stage during powder compaction,which can significantly affect the product quality and *** this paper,a forced feeder is introduced attempting to improve the filling performance of a lab-scale die filling *** die filling process is analysed with a graphics processing units(GPU)enhanced discrete element method(DEM).Various stirrer designs are assessed for a wide range of process settings(i.e.,stirrer speed,filling speed)to explore their influence on the die filling performance of free-flowing *** results show that die filing with the novel helical-ribbon(i.e.,type D)stirrer design exhibits the highest filling ratio,implying that it is the most robust stirrer design for the feeder configuration ***,die filling performance with the type D stirrer design is a function of the stirrer speed and the filling speed.A positive variation of filling ratio(ηf>0%)can be ensured over the whole range of filling speed by adjusting the stirrer speed(i.e.,increasing the stirrer speed).The approach used in this study can not only help understand how the stirrer design affects the die filling performance but also guide the optimization of feeder system and process settings.

关键词： Discrete element method Die filling Forced feeding Stirrer design GPU computing

Efficient removal of the recalcitrant metamizole contaminant from drinking water by using a CaLaCoO_(9) perovskite supported on recycled polyethylene

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Journal of Environmental Sciences 2024年第2期136卷 56-67页

作者： Ernesto Valadez-Renteria Christian Perez-Carrasco Dulce Yolotzin medina-Velazquez Vicente Rodriguez-Gonzalez Jorge Oliva CONACYT-División de Materiales Avanzados Instituto Potosino de Investigación Científica y Tecnológica A.C.San Luis PotosíSLP 78216México División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana AzcapotzalcoCol.Reynosa-TamaulipasC.P.MéxicoDF 02200México

Metamizole(MZ)is a widely used anti-inflammatory *** to its common use,this contaminant is found in sewage and *** order to reduce the contamination produced by the MZ,we fabricated in this work a photocatalytic composite using recycled polyethylene(RPE)and the CaLaCoO_(9)(LCCO)*** nanoparticles had a microplate-like morphology and sizes of 1.4–5.5μm according to the analysis of *** photocatalytic properties of the LCCO powders were evaluated under ultraviolet-visible(UV-Vis)irradiation and found a removal efficiency of 96%.When the RPE+LCCO composite was employed for the photocatalytic degradation of MZ,a maximum degradation of 92.5%was *** influence of the pH on the photocatalytic activity was also studied and found that an initial pH=3 produced a total degradation of MZ after 240 min of UV-Vis ***,three reuse cycles were carried out for the pure LCCO powders and for the RPE+LCCO composites and found that the maximum loss of degradation was 5%.Furthermore,scavenger experiments demonstrated that the super oxide and hydroxyl radicals are formed during the photocatalytic reaction and were responsible for the degradation of ***,the X-ray photoelectron-spectroscopy and Raman analysis demonstrated the formation of defects(oxygen vacancies),those ones delayed the electron-hole recombination,which in turn,enhanced the degradation of the ***,the studies performed in this work proved that composites made with recycled plastics and LCCO perovskites are a low-cost and feasible alternative for the cleaning of water sources polluted with pharmaceutical compounds.

关键词： Photocatalysis Metamizole Pharmaceutical contaminant UV-Vis irradiation Perovskite

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Elements of Electromagnetic Matter

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Journal of Modern Physics 2024年第3期15卷 250-270页

作者： Viktor ariel Independent Researcher Modiin Israel

Originally, Maxwell attempted to express his electromagnetic theory using four-dimensional mathematics of quaternions. Maxwell’s equations were later re-written in a three-dimensional real vector form, which is how the theory is presented today. Thus, an interesting question remains whether we can derive electromagnetic equations analytically from the basic mathematical principles of quaternion algebra and calculus, resulting in general and analytic matter equations. This question seems highly intriguing. Previously, we developed a mathematical theory of time using a normed division algebra of real quaternions [1]. In this study, we extend the theory of time by presenting a new analytical derivation of electromagnetic matter equations using the calculus of real quaternions, as originally intended by Maxwell. Therefore, we propose a novel mathematical definition of the quaternion path derivative using the properties of quaternion division. We then apply the quaternion derivative to an external electromagnetic potential and assume that the first quaternion derivative represents the quaternion electromagnetic force. Next, we assume that the second derivative, or quaternion Laplacian operator, applied to an external electromagnetic potential leads to the quaternion electromagnetic current density. The new analytical expressions are similar to the original empirical Maxwell equations, except for an additional scalar electric field, which allows for a novel formulation of Ohm’s conductivity law. We demonstrate that the resulting analytical equations can be written equivalently using either electromagnetic potentials or fields. Finally, we summarize the key postulates and equations of the new electromagnetic matter theory, which were based on normed division algebra and the calculus of quaternions. The resulting theory appears to be a useful analytical enhancement of the original Maxwell equations, and therefore, seems highly comprehensive, logical, and compelling.

关键词： Maxwell’s Equations Relativistic Electrodynamics Quaternion Calculus

Interactions between maternal parity and feed additives drive the composition of pig gut microbiomes in the post‑weaning period

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1241-1257页

作者： Kayla Law Eduardo Rosa medina Garcia Chad Hastad Deborah Murray Pedro E.Urriola Andres Gomez Department of Animal Science University of Minnesota1364 Eckles AvenueSaint PaulMN 55108USA New Fashion Pork 164 Industrial ParkwayJacksonMN 56143USA

Background Nursery pigs undergo stressors in the post-weaning period that result in production and welfare *** challenges disproportionately impact the offspring of primiparous sows compared to those of mul-tiparous *** is known regarding potential interactions between parity and feed additives in the post-weaning period and their effects on nursery pig ***,the objective of this study was to investigate the effects of maternal parity on sow and offspring microbiomes and the influence of sow parity on pig fecal microbi-ome and performance in response to a prebiotic *** weaning,piglets were allotted into three treat-ment groups:a standard nursery diet including pharmacological doses of Zn and Cu(Con),a group fed a commercial prebiotic only(Preb)based on an Aspergillus oryzae fermentation extract,and a group fed the same prebiotic plus Zn and Cu(Preb+ZnCu).Results Although there were no differences in vaginal microbiome composition between primiparous and mul-tiparous sows,fecal microbiome composition was different(R^(2)=0.02,P=0.03).The fecal microbiomes of primiparous offspring displayed significantly higher bacterial diversity compared to multiparous offspring at d 0 and d 21 post-weaning(P<0.01),with differences in community composition observed at d 21(R^(2)=0.03,P=0.04).When analyzing the effects of maternal parity within each treatment,only the Preb diet triggered significant microbiome distinc-tions between primiparous and multiparous offspring(d 21:R^(2)=0.13,P=0.01;d 42:R^(2)=0.19,P=0.001).Composi-tional differences in pig fecal microbiomes between treatments were observed only at d 21(R^(2)=0.12,P=0.001).Pigs in the Con group gained significantly more weight throughout the nursery period when compared to those in the Preb+ZnCu *** Nursery pig gut microbiome composition was influenced by supplementation with an Aspergillus oryzae fermentation extract,with varying effects on performance

关键词： Aspergillus prebiotic Copper Feed additives Maternal Nursery pig microbiome Parity Swine microbiome Trace minerals Zinc

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Polyoxidovanadates a new therapeutic alternative for neurodegenerative and aging diseases

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Neural Regeneration Research 2024年第3期19卷 571-577页

作者： Sonia Irais Gonzalez-Cano Gonzalo Flores Jorge Guevara Julio Cesar Morales-medina Samuel Treviño Alfonso Diaz Faculty of Chemical Sciences Benemerita Autonomous University of PueblaPueblaMexico Institute of Physiology Benemerita Autonomous University of PueblaPueblaMexico Department of Biochemistry Faculty of MedicineNational Autonomous University of MexicoMexico CityMexico Animal Reproduction Research Center CINVESTAV-Autonomous University of TlaxcalaTlaxcalaMexico

Aging is a natural phenomenon characterized by a progressive decline in physiological integrity,leading to a deterioration of cognitive function and increasing the risk of suffering from chronic-degenerative diseases,including cardiovascular diseases,osteoporosis,cancer,diabetes,and *** is considered the major risk factor for Parkinson’s and Alzheimer’s disease ***,diabetes and insulin resistance constitute additional risk factors for developing neurodegenerative ***,no treatment can effectively reverse these neurodegenerative ***,some antidiabetic drugs have opened the possibility of being used against neurodegenerative *** the previous framework,Vanadium species have demonstrated a notable antidiabetic *** research group evaluated polyoxidovanadates such as decavanadate and metforminium-decavanadate with preventive and corrective activity on neurodegeneration in brain-specific areas from rats with metabolic *** results suggest that these polyoxidovanadates induce neuronal and cognitive restoration *** review aims to describe the therapeutic potential of polyoxidovanadates as insulin-enhancer agents in the brain,constituting a therapeutic alternative for aging and neurodegenerative diseases.

关键词： Alzheimer’s disease antidiabetic brain cognition diabetes insulin neurodegeneration neuroinflammation oxidative stress Vanadium species

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Liquid biopsy for gastric cancer:Techniques,applications,and future directions

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World Journal of Gastroenterology 2024年第12期30卷 1680-1705页

作者： Cristina Díaz del Arco M Jesús Fernández Aceñero Luis Ortega medina Department of Surgical Pathology Health Research Institute of the Hospital Clínico San CarlosHospital Clínico San CarlosMadrid 28040Spain Department of Legal Medicine Psychiatry and PathologyUniversidad Complutense de MadridMadrid 28040Spain

After the study of circulating tumor cells in blood through liquid biopsy(LB),this technique has evolved to encompass the analysis of multiple materials originating from the tumor,such as nucleic acids,extracellular vesicles,tumor-educated platelets,and other ***,research has extended to include the examination of samples other than blood or plasma,such as saliva,gastric juice,urine,or *** techniques are diverse,intricate,and *** must be highly sensitive,and pre-analytical,patient,and tumor-related factors significantly influence the detection threshold,diagnostic method selection,and potential ***,the implementation of LB in clinical practice still faces several *** potential applications of LB range from early cancer detection to guiding targeted therapy or immunotherapy in both early and advanced cancer cases,monitoring treatment response,early identification of relapses,or assessing patient *** the other hand,gastric cancer(GC)is a disease often diagnosed at advanced *** recent advances in molecular understanding,the currently available treatment options have not substantially improved the prognosis for many of these *** application of LB in GC could be highly valuable as a non-invasive method for early diagnosis and for enhancing the management and outcomes of these *** this comprehensive review,from a pathologist’s perspective,we provide an overview of the main options available in LB,delve into the fundamental principles of the most studied techniques,explore the potential utility of LB application in the context of GC,and address the obstacles that need to be overcome in the future to make this innovative technique a game-changer in cancer diagnosis and treatment within clinical practice.

关键词： Liquid biopsy Gastric cancer Circulating tumor cells Cell-free DNA Circulating tumor DNA Molecular

Towards an integrated risk analysis security framework according to a systematic analysis of existing proposals

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Frontiers of Computer Science 2024年第3期18卷 199-216页

作者： Antonio SANTOS-OLMO Luis Enrique SÁNCHEZ David G.ROSADO Manuel A.SERRANO Carlos BLANCO Haralambos MOURATIDIS Eduardo FERNÁNDEZ-medina GSyA Research Group University of Castilla-La ManchaCiudad Real 13071Spain Institute for Analytics and Data Science University of EssexColchester CO43SQUK Alarcos Research Group University of Castilla-La ManchaCiudad Real 13071Spain ISTR Research group Department of Computer Science and ElectronicsUniversity of CantabriaSantander 39005Spain

The information society depends increasingly on risk assessment and management systems as means to adequately protect its key information *** availability of these systems is now vital for the protection and evolution of ***,several factors have led to an increasing need for more accurate risk analysis *** are:the speed at which technologies evolve,their global impact and the growing requirement for companies to *** analysis processes must consequently adapt to these new circumstances and new technological *** objective of this paper is,therefore,to present the results of an exhaustive analysis of the techniques and methods offered by the scientific community with the aim of identifying their main weaknesses and providing a new risk assessment and management *** analysis was carried out using the systematic review protocol and found that these proposals do not fully meet these new *** paper also presents a summary of MARISMA,the risk analysis and management framework designed by our research *** basis of our framework is the main existing risk standards and proposals,and it seeks to address the weaknesses found in these *** is in a process of continuous improvement,as is being applied by customers in several European and American *** consists of a risk data management module,a methodology for its systematic application and a tool that automates the process.

关键词： information security management security system security risk assessment and management