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The Origin of Cosmic Structures Part 6: CMB Anisotropy

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j.urnal of High Energy Physics, gravitation and Cosmology 2024年第1期10卷 257-276页

作者： j. C. Botke Ronin Institute Montclair New Jersey USA

In a recent series of papers, we introduced a new model of nucleosynthesis in which the matter content of the universe came into existence at a time of about 4 × 10-5 s. At that time, a small percentage of the vacuum energy was converted into neutron/antineutron pairs with a very small excess of neutrons. This process was regulated by an imprint that was established in the vacuum during an initial Plank-era inflation. Immediately after their inception, annihilation and charge exchange reactions proceeded at a very high rate and ran to completion after an interval of about 10-11 s. By then, all the antibaryons had disappeared thereby establishing the matter/antimatter asymmetry of the universe. What remained were very high densities of mesons and leptons, somewhat lower densities of protons and neutrons, and finally, the very high density of photons that eventually became the CMB. The density of matter so created varied from one location to another in such a manner as to account for all cosmic structures and because the energy density of the photons varied in proportion to that of the matter, the CMB-to-be came into existence with an anisotropic spectrum already in place. For structures, the size of galaxy clusters, the initial anisotropy magnitudes were on the order of 25%. In this paper, we will follow the subsequent evolution of the photons and show that this model predicts with accuracy the temperature of the warmest anisotropies in the observed CMB spectrum. .

关键词： CMB Anisotropy Dispersion Nucleosynthesis Early Universe Time-Varying Curvature

Modeling of Total Dissolved Solids (TDS) and Sodium Absorption Ratio (SAR) in the Edwards-Trinity Plateau and Ogallala Aquifers in the Midland-Odessa Region Using Random Forest Regression and eXtreme gradient Boosting

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j.urnal of geoscience and Environment Protection 2024年第5期12卷 218-241页

作者： Azuka I. Udeh Osayamen j. Imarhiagbe Erepamo j. Omietimi Department of geoscience University of Texas Permian Basin Odessa Texas USA Department of geology University of Pretoria Pretoria South Africa

Efficient water quality monitoring and ensuring the safety of drinking water by government agencies in areas where the resource is constantly depleted due to anthropogenic or natural factors cannot be overemphasized. The above statement holds for West Texas, Midland, and Odessa Precisely. Two machine learning regression algorithms (Random Forest and XgBoost) were employed to develop models for the prediction of total dissolved solids (TDS) and sodium absorption ratio (SAR) for efficient water quality monitoring of two vital aquifers: Edward-Trinity (plateau), and Ogallala aquifers. These two aquifers have contributed immensely to providing water for different uses ranging from domestic, agricultural, industrial, etc. The data was obtained from the Texas Water Development Board (TWDB). The XgBoost and Random Forest models used in this study gave an accurate prediction of observed data (TDS and SAR) for both the Edward-Trinity (plateau) and Ogallala aquifers with the R2 values consistently greater than 0.83. The Random Forest model gave a better prediction of TDS and SAR concentration with an average R, MAE, RMSE and MSE of 0.977, 0.015, 0.029 and 0.00, respectively. For the XgBoost, an average R, MAE, RMSE, and MSE of 0.953, 0.016, 0.037 and 0.00, respectively, were achieved. The overall performance of the models produced was impressive. From this study, we can clearly understand that Random Forest and XgBoost are appropriate for water quality prediction and monitoring in an area of high hydrocarbon activities like Midland and Odessa and West Texas at large.

关键词： Water Quality Prediction Predictive Modeling Aquifers Machine Learning Regression eXtreme gradient Boosting

Towards efficient strain engineering of 2D materials:A four-points bending approach for compressive strain

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Nano Research 2024年第6期17卷 5317-5325页

作者： Hao Li Félix Carrascoso Ana Borrás gloria P.Moreno Francisco j.Aparicio Ángel Barranco Andrés Castellanos gómez Campus de Cantoblanco Instituto de Ciencia de Materiales de MadridC.Sor Juana Inés de la Cruz328049 MadridSpain Nanotechnology on Surfaces and Plasma Lab Instituto de Ciencia de Materiales de Sevilla(CSIC-Universidad de Sevilla).C/Americo Vespucio 49E-41092 SevilleSpain Departamento de Física Aplicada I Escuela Politécnica SuperiorUniversidad de Sevillac/Virgen deÁfrica 7E-41011 SevilleSpain

Strain engineering,as a powerful strategy to tune the optical and electrical properties of two-dimensional(2D)materials by deforming their crystal lattice,has attracted significant interest in recent years.2D materials can sustain ultra-high strains,even up to 10%,due to the lack of dangling bonds on their surface,making them ideal brittle *** remarkable mechanical resilience,together with a strong strain-tunable band structure,endows 2D materials with a broad optical and electrical response upon ***,strain engineering based on 2D materials is restricted by their nanoscale and strain quantification *** this study,we have modified a homebuilt three-points bending apparatus to transform it into a four-points bending apparatus that allows for the application of both compressive and tensile strains on 2D *** approach allows for the efficient and reproducible construction of a strain system and minimizes the buckling effect caused by the van der Waals interaction by adamantane encapsulation *** results demonstrate the feasibility of introducing compressive strain on 2D materials and the potential for tuning their optical and physical properties through this approach.

关键词： uniaxial compressive strain polymer encapsulation differential reflectance spectroscopy exciton tunability

Highly divergent sympatric lineages of Leptotila verreauxi(Aves:Columbidae)suggest a secondary contact area in the Isthmus of Tehuantepec,Mexico

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Avian Research 2024年第1期15卷 12-21页

作者： Orlando j.Espinosa-Chávez Adolfo g.Navarro-Sigüenza Hernando Rodríguez-Correa Luis A.Sánchez-gonzález Museo de Zoología“Alfonso L.Herrera” Depto.de Biología EvolutivaFacultad de CienciasUniversidad Nacional Autonoma de MexicoApdo.Postal 70-399CP 04510Ciudad de MexicoMexico Posgrado en Ciencias Biologicas Unidad de PosgradoEdificio D1◦PisoCircuito de PosgradosCiudad UniversitariaUniversidad Nacional Autonoma de MexicoCoyoacanCP 04510CDMXMexico Escuela Nacional de Estudios Superiores Unidad Morelia Universidad Nacional Autonoma de Mexico.Antigua Carretera a Patzcuaro No.8701 Col.Ex Hacienda de San Jose de la HuertaC.P.58190MoreliaMichoacanMexico

Due to a complex geological and biotic history,the Isthmus of Tehuantepec(IT),has been long recognized as a driver for the evolutionary divergence of numerous lowland and highland *** distributed in the lowlands of the American continent,the White-Tipped Dove(Leptotila verreauxi)is a polytypic species with 13 recognized *** of these have been recorded in Mexico,and the distribution of three abuts at the IT,suggesting a contact *** estimate phylogenetic patterns,divergence times and genetic differentiation,we examined two mt DNA(ND2 and COI)and one n DNA(β-fibint 7)*** also used correlative ecological niche models(ENM)to assess whether ecological differences across the IT may have acted as a biogeographical *** estimated paleodistributions during the Middle Holocene,Last glacial Maximum and Last Interglacial,to evaluate the influence of climate changes on the distribution and demographic *** results showed genetically distinct lineages that diverged approximately 2.5 million years *** and ecological factors may have played a dual role in promoting differentiation,but also in the formation of a secondary contact zone in the southern *** ecological niche comparisons indicated that the ecological niche of sympatric lineages at the IT are not identical,suggesting niches divergence;in addition,environmental niche models across the region indicated no abrupt biogeographic barriers,but the presence of regions with low *** results suggest that genetic differentiation originated by a vicariant event probably related to environmental factors,favored the evolution of different ecological ***,the absence of a biogeographic barrier but the presence of less suitable areas in the contact regions,suggest that secondary contact zones may be also maintained by climatic factors for the eastern group,but also by biotic interactions for the western group.

关键词： Biogeographical boundary Humid and dry forests Isthmus of Tehuantepec Phylogeography Secondary contact

Identific tion of quantitative trait loci and associated candidate genes for pregnancy success in Angus–Brahman crossbred heifers

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j.urnal of Animal Science and Biotechnology 2024年第1期15卷 162-170页

作者： Quinn A.Hoorn gabriel A.Zayas Eduardo E.Rodriguez Laura M.j.nsen Raluca g.Mateescu Peter j.Hansen Department of Animal Sciences Donald Henry Barron Reproductive and Perinatal Biology Research Programand the Genetics InstituteUniversity of FloridaGainesvilleFLUSA School of Applied Systems Biology La Trobe UniversityBundooraVIC 3083Australia

Background In beef cattle, more than 50% of the energy input to produce a unit of beef is consumed by the female that produced the calf. Development of genomic tools to identify females with high genetic merit for reproductive function could increase the profitability and sustainability of beef *** genome-wide association studies(gWAS) were performed using a single-step genomic best linear unbiased prediction approach on pregnancy outcome traits from a population of Angus–Brahman crossbred heifers. Furthermore, a validation gWAS was performed using data from another farm. Heifers were genotyped with the Bovine ggP F250 array that contains 221,077 SNPs. In the discovery population, heifers were bred in winter breeding seasons involving a single round of timed artificial insemination(AI) followed by natural mating for 3 months. Two phenotypes were analyzed: pregnancy outcome to first-service AI(PAI;n = 1,481) and pregnancy status at the end of the breeding season(PEBS;n = 1,725). The heritability was estimated as 0.149 and 0.122 for PAI and PEBS, respectively. In the PAI model, one quantitative trait locus(QTL), located between 52.3 and 52.5 Mb on BTA7, explained about 3% of the genetic variation, in a region containing a cluster of γ-protocadherin genes and SLC25A2. Other QTLs explaining between 0.5% and 1% of the genetic variation were found on BTA12 and 25. In the PEBS model, a large QTL on BTA7 was synonymous with the QTL for PAI, with minor QTLs located on BTA5, 9, 10, 11, 19, and 20. The validation population for pregnancy status at the end of the breeding season were Angus–Brahman crossbred heifers bred by natural mating. In concordance with the discovery population, the large QTL on BTA7 and QTLs on BTA10 and 12 were *** In summary, QTLs and candidate SNPs identified were associated with pregnancy outcomes in beef heifers, including a large QTL associated with a group of protocadherin genes. Confirmation of these associations

关键词： Beef cattle Fertility gWAS QTL

Influence of Heavy Fuel Oil on the Thermo-Physical and Erodibility Properties of Earthen Materials

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j.urnal of Minerals and Materials Characterization and Engineering 2024年第1期12卷 37-48页

作者： Ohindemi g. Yameogo Donzala D. Some Souleymane Ouedraogo Philbert Nshimiyimana Sié Kam Dieudonné j. Bathiebo Laboratoire d’Energies Thermiques Renouvelables (L.E.T.RE) Unité de Formation et de Recherche en Sciences Exactes et Appliquées (UFR-SEA) University Joseph Ki-Zerbo of Ouagadougou Ouagadougou Burkina Faso Ministry in Charge of Infrastructures Ouagadougou Burkina Faso Department of Civil Engineering and Architectural Design Graduate School of Science and Engineering Saga University Saga Japan Laboratoire Eco-Matériaux et Habitats Durables (LEMHaD) Institut International d’Ingénierie de l’Eau et de L’Environnement (Institut 2iE) Ouagadougou Burkina Faso

This study focuses on the use of heavy fuel oil in construction material in Burkina Faso. Its mixture with silty or clayey soil is used as a coating to reinforce the walls of raw earth constructions which are very sensitive to water. The interest of this study is to determine erodibility, water content, while highlighting the influence of the porosity accessible by water on thermal diffusion in construction material containing heavy fuel oil. The heavy fuel oil was mixed with a silty-clayey soil, in different proportions, and water to make bricks samples on which tests were carried out. At the end of the experimental tests, it appears that the water content increases gradually, but not significantly with the addition of heavy fuel oil, which causes a slight increase in the speed of heat propagation through the material with reduced porosity, particularly those containing higher quantities of heavy fuel oil. Conversely, we note a good performance of heavy fuel oil in terms of water resistance properties such as porosity accessible by water and erodibility. This allows us to conclude that the mixture of heavy fuel oil and silty-clayey soil used as a coating material could greatly reduce water infiltration into the walls of housing constructions with raw earthen materials.

关键词： Porosity Accessible by Water Erodibility Water Content Thermal Diffusion

Quantitative Identification of Delamination Damage in Composite Structure Based on Distributed Optical Fiber Sensors and Model Updating

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SDHM Structural Durability and Health Monitoring 2024年第6期18卷 785-803页

作者： Xu H. Wang j. Zhu R. Strauss A. Cao M. Wu Z. School of Materials Science and Engineering Dalian University of Technology Dalian 116000 China School of Mechanics and Aerospace Engineering Dalian University of Technology Dalian 116000 China Department of Civil Engineering and Natural Hazards University of Natural Resources and Life Sciences Vienna 1180 Austria Department of Engineering Mechanics Hohai University Nanjing China

Delamination is a prevalent type of damage in composite laminate structures. Its accumulation degrades structural performance and threatens the safety and integrity of aircraft. This study presents a method for the quantitative identification of delamination identification in composite materials, leveraging distributed optical fiber sensors and a model updating approach. Initially, a numerical analysis is performed to establish a parameterized finite element model of the composite plate. Then, this model subsequently generates a database of strain responses corresponding to damage of varying sizes and locations. The radial basis function neural network surrogate model is then constructed based on the numerical simulation results and strain responses captured from the distributed fiber optic sensors. Finally, a multi-island genetic algorithm is employed for global optimization to identify the size and location of the damage. The efficacy of the proposed method is validated through numerical examples and experiment studies, examining the correlations between damage location, damage size, and strain responses. The findings confirm that the model updating technique, in conj.nction with distributed fiber optic sensors, can precisely identify delamination in composite structures. © 2024 The Authors. Published by Tech Science Press.

关键词： Composite structures damage identification fiber optic sensor model updating surrogate model

Electricity generation from Heatwaves

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International j.urnal of geosciences 2024年第5期15卷 449-457页

作者： Diandong Ren Mervyn j. Lynch School of Electrical Engineering Computing and Mathematical Sciences Curtin University Perth Australia Australian Sustainable Development Institute (ASDI) Perth Australia

We chose a definition of heatwaves (HWs) that has ~4-year recurrence frequency at world hot spots. We first examined the 1940-2022 HWs climatology and trends in lifespan, severity, spatial extent, and recurrence frequency. HWs are becoming more frequent and more severe for extratropical mid- and low-latitudes. To euphemize HWs, we here propose a novel clean energy-tapping concept that utilizes the available nano-technology, micro-meteorology knowledge of temperature distribution within/without buildings, and radiative properties of earth atmosphere. The key points for a practical electricity generation scheme from HWs are defogging, insulation, and minimizing the absorption of infrared downward radiation at the cold legs of the thermoelectric generators. One sample realization is presented which, through relay with existing photovoltaic devices, provides all-day electricity supply sufficient for providing air conditioning requirement for a residence (~2000-watt throughput). The provision of power to air conditioning systems, usually imposes a significant stress on traditional city power grids during heatwaves.

关键词： Heatwaves Climate Warming Clean Energy generation by Thermoelectric generator Ameliorate and Transcend Heatwaves Climate Warming Mitigation and Adaptation Thermoelectric generator (TEg) IR Interaction with Periodically Arranged Nanostructures Optical Properties of Nano Fabricating Passive Clean Energy Tapping/generation

Why Don’t We Adequately Identify and Manage Adverse Drug Reactions despite Having the Needed Information?

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Health 2024年第2期16卷 148-159页

作者： Mark j. Kupersmith Karl Kieburtz Department of Neurology Ophthalmology and Neurosurgery Icahn School of Medicine at Mount Sinai New York NY USA SafeTherapeutics LLC New York NY USA Clintrex Research Corporation Sarasota FL USA

Importance/Obj.ctive: Adverse Drug Reactions (ADRs) are unavoidable, but recognizing and addressing ADRs early can improve wellness and prevent permanent inj.ry. We suggest that available medical information and digital/electronic methods could be used to manage this maj.r healthcare problem for individual patients in real time. Methods: We searched the available digital applications and three literature databases using the medical subj.ct heading terms, adverse drug reaction reporting systems or management, filtered by clinical trial or systemic reviews, to detect publications with data about ADR identification and management approaches. We reviewed the reports that had abstract or summary data or proposed or implemented methods or systems with potential to identify or manage ADRs in clinical settings. Results: The vast maj.rity of the 481 reports used retrospectively collected data for groups of patients or were limited to surveying one population group or class of medication. The reports showed potential and definite associations of ADRs for specific drugs and problems, mostly, but not exclusively, for patients in hospitals and nursing homes. No reports described complete methods to collect comprehensive data on ADRs for individual patients in a healthcare system. The digital applications have ADR information, but all are too cumbersome or incomplete for use in active clinical settings. Several studies suggested that providing information about potential ADRs to clinicians can reduce these problems. Conclusion and Relevance: Although investigators and government agencies agree with the need, there is no comprehensive ADR management program in current use. Informing the patient’s healthcare practitioners of potential ADRs at the point of service has the potential for reduction of these complications, which should improve healthcare and reduce unneeded costs.

关键词： Adverse Drug Reaction Medication Side Effect Identification Medication Complication Medication Safety