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performance of evolutionary optimized machine learning for modeling total organic carbon in core samples of shale gas fields

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petroleum 2024年第1期10卷 150-164页

作者： Leonardo Goliatt c.M.Saporetti L.c.Oliveira E.pereira Department of computational and Applied Mechanics Federal University of Juiz de Fora Department of computational Modeling Polytechnic Institute Rio de Janeiro State University petrobras Department of Stratigraphy and paleontology Rio de Janeiro State University

Rock samples' TOc content is the best indicator of the organic matter in source rocks. The origin rock samples' analysis is used to calculate it manually by specialists. This method requires time and resources because it relies on samples from many well intervals in source rocks. Therefore, research has been done to aid this effort. Machine learning algorithms can estimate total organic carbon instead of well logs and stratigraphic studies. In light of these efforts, the current work present a study on automating the total organic carbon estimation using machine learning approaches improved by an evolutionary methodology to give the model flexibility and precision. Genetic algorithms, differential evolution, particle swarm optimization, grey wolf optimization, artificial bee colony, and evolution strategies were used to improve machine learning models to predict TOc. The six metaheuristics were integrated into four machine learning methods: extreme learning machine, elastic net linear model, linear support vector regression, and multivariate adaptive regression splines. core samples from the YuDong-Nan shale gas field, located in the Sichuan basin, were used to evaluate the hybrid strategy. The findings show that combining machine learning models with an evolutionary algorithms in a hybrid fashion produce flexible models that accurately predict TOc. The results show that, independent of the metaheuristic used to guide the model selection, optimized extreme learning machines attained the best performance scores according to six metrics. Such hybrid models can be used in exploratory geological research,particularly for unconventional oil and gas resources.

关键词： Total organic carbon Hybrid models Automated machine learning Evolutionary algorithms Geology

Measurement of yields and angular distributions ofγ-quanta from the interaction of 14.1 MeV neutrons with oxygen,phosphorus,and sulfur

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chinese physics c 2024年第3期48卷 79-92页

作者： D.N.Grozdanov N.A.Fedorov S.B.Dabylova Yu.N.Kopatch I.N.Ruskov V.R.Skoy T.Yu.Tretyakova c.Hramco p.I.Kharlamov G.V.pampushik p.G.Filonchik A.V.Andreev Joint Institute for Nuclear Research(JINR) DubnaRussia Institute for Nuclear Research and Nuclear Energy Bulgarian Academy of SciencesSofiaBulgaria Faculty of physics Lomonosov Moscow State UniversityMoscowRussia L.N.Gumilyov Eurasian National University AstanaKazakhstan Skobeltsyn Institute of Nuclear physics Moscow State UniversityMoscowRussia Institute of chemistry of Moldova ChisinauRepublic of Moldova Moscow Institute of physics and Technology MoscowRussia

A study of the inelastic scattering of neutrons with an energy of 14.1 MeV on the nuclei of oxygen,phosphorus,and sulfur was performed at the TANGRA facility at JINR(Dubna).The experiment aimed to refine existing data and obtain new data on the yields and angular distributions ofγ-quanta emitted by the studied nuclei due to neutron-induced nuclear reactions using the tagged neutron *** types of detector systems were used to registerγ-***γ-ray yields were measured using a high-purity germanium(HpGe)*** angular distributions ofγ-rays were obtained using a system of 18 scintillation detectors based on bismuth germanite Bi_(4)Ge_(3)O_(12)(BGO)located around the *** performed experiments measured the yields of two transitions for the reaction of tagged neutrons with 16O,nine transitions for the reaction with ^(31)p,and nine transitions for the reaction with ^(32)S for the first *** angular anisotropy of theγ-radiation accompanying the inelastic scattering of neutrons with an energy of 14.1 MeV on ^(31)p nuclei was also measured for the first time.

关键词： tagged neutron method yields of gamma-quanta high-resolution gamma-spectrometry neutron-nuclear reactions neutron scattering

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富氮气调--磷化氢的可供替换技术

粮油食品科技 2024年第3期32卷 55-68页

作者： Manjree agarwal James NEWMAN Yan-yu LI Li GU Bei-bei LI Yong-lin REN 李燕羽(译) 西澳大利亚政府化学中心澳大利亚珀斯WA 6102 cBH澳大利亚谷物有限公司澳大利亚珀斯WA 6000 默多克大学环境和生命科学学院澳大利亚珀斯WA 6150 国家粮食和物资储备局科学研究院粮食储运研究所北京100037 国家粮食和物资储备局科学研究院粮食储运研究所

在粮食储藏上利用氮气的方法已经有30多年的历史,但直到最近经济有效的变压吸附(pSA)和膜分离(MS)制氮设备的出现,才使得该技术在储粮上使用成为可能。本研究首先在25、30和35℃、99%、98%和97%氮气的环境下,对小麦、大麦、燕麦、羽扇... 详细信息

在粮食储藏上利用氮气的方法已经有30多年的历史,但直到最近经济有效的变压吸附(pSA)和膜分离(MS)制氮设备的出现,才使得该技术在储粮上使用成为可能。本研究首先在25、30和35℃、99%、98%和97%氮气的环境下,对小麦、大麦、燕麦、羽扇豆和油菜籽中的花斑皮蠹、赤拟谷盗、谷蠹和米象成虫和非成虫虫态进行了为期4、3和2周的实验室生物测定。然后在终端用户LakeGrace和cBH(cooperative BulkHandling)谷物进出口公司Albany出口港码头开展实仓验证,测定小麦、大麦和油菜籽中不同储粮害虫虫种和油菜籽瓢虫和肖叶甲类两种田间害虫的防治效果。同时对处理后的粮食品质进行了测定。实验结果表明,害虫死亡率随着氧气浓度降低、暴露时间和温度的增加而增加,富氮低氧在低温条件下不能100%致死花斑皮蠹幼虫。氮气处理对磷化氢抗性和敏感品系储粮害虫防治效果没有差异。与其他粮种相比,在油菜籽中的防治效果更好。各种粮种的水分含量、蛋白质、含油量、淀粉和籽粒颜色品质指标均未受到影响。成功开发了富氮低氧商业规模应用模式,为磷化氢高抗性害虫治理提供了解决方案,满足市场日益增长对无害虫和无化学残留粮食的需求。

关键词：气调储藏害虫治理磷化氢抗药性粮食品质应用模式

Antioxidant treatment for oligoasthenoteratozoospermia and varicocele:a DBpc trial to evaluate the impact of age and body mass index

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Asian Journal of Andrology 2024年第3期26卷 239-244页

作者： Gian Maria Busetto Bernarde F Rodrigues Ashraf Virmani Andrea checchia Antonella Ninivaggi Anna Ricapito Giovanni Barbieri piero Fischetti Ugo G Falagario pasquale Annese Nicola d’Altilia Vito Mancini Matteo Ferro Felice crocetto Angelo porreca carlo Bettocchi Luigi cormio Ashok agarwal Giuseppe carrieri University of Foggia Foggia 71122Italy Department of Urology and Renal Transplantation Policlinico of FoggiaFoggia 71122Italy Department of Urology Human Reproduction SectionFederal University of Sao PauloSao Paulo 05403-000Brazil Alfasigma Healthscience Utrecht 3528 BGThe Netherlands Urology Unit “G.Tatarella”HospitalCerignola 71042Italy Urology Unit European Institute of Oncology(IEO)IRCCSMilan 20142Italy University of Naples Federico II Naples80126Italy Department of Oncological Urology Veneto Institute of Oncology(IOV)IRCCSPadua 35039Italy Urology Unit “L.Bonomo”HospitalAndria 70031Italy Global Andrology Forum Moreland HillsOH 44022USA

Oxidative stress is one of the main mechanisms responsible for male *** conditions such as varicocele,obesity,advanced age,and lifestyle can lead to an increase in reactive oxygen species,causing an oxidative imbalance in the *** are sensitive to reactive oxygen species and require energy to carry out their main function of fertilizingthe *** reactive oxygen species can affect sperm metabolism,leading to immobility,impaired acrosome reaction,and celldeath,thereby impairing reproductive *** double-blind randomized study evaluated the effect of supplementation withL-carnitine,acetyl-L-carnitine,vitamins,and other nutrients on semen quality in 104 infertile patients with or without varicocele,while also investigating the impact of factors such as obesity and advanced age on *** concentration significantlyincreased in the supplemented group compared to the placebo group(p=0.0186).Total sperm count also significantly increasedin the supplemented group(p=0.0117),as did sperm motility(p=0.0120).The treatment had a positive effect on patients upto 35 years of age in terms of sperm concentration(p=0.0352),while a body mass index(BMI)above 25 kg m^(−2) had a negativeeffect on sperm concentration(p=0.0110).Results were not showing a net benefit in stratifying patients in accordance withtheir BMI since sperm quality increase was not affected by this *** conclusion,antioxidant supplementation may bebeneficial for infertile patients and has a more positive effect on younger patients with a normal weight.

关键词： aging antioxidants body mass index oligoasthenoteratozoospermia varicocele

proteins as nanomagnets and magnetoreceptors

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Zoological Research 2024年第4期45卷 831-832页

作者： p.J.Hore Department of chemistry University of OxfordUK

It is an appealing notion that a protein molecule could act as a nanomagnet.A genetically encodable biomolecule with a permanent magnetic moment at room temperature could have a range of applications:a magnetogenetic actuator,a magnetic tag for purifying and immobilizing enzymes,a contrast agent for magnetic resonance imaging,and a basis for a biomimetic magnetic sensing device,to name just a few.A magnetic protein could perhaps also function as the sensor in the magnetic compass that enables small songbirds to navigate the huge distances between their breeding and wintering *** though such possibilities may be,how realistic are they?

关键词： magnetic magnets enable

The great catastrophe: causes of the permo-Triassic marine mass extinction

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National Science Review 2024年第1期11卷 37-50页

作者： paul B.Wignall David p.G.Bond School of Earth & Environment University of Leeds School of Environmental Sciences University of Hull

The marine losses during the permo-Triassic mass extinction were the worst ever experienced. All groups were badly affected, especially amongst the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). planktonic populations underwent a fundamental change with eukaryotic algae being replaced by nitrogen-fixing bacteria, green-sulphur bacteria, sulphate-reducing bacteria and prasinophytes. Detailed studies of boundary sections, especially those in South china, have resolved the crisis to a ～55 kyr interval straddling the permo-Triassic boundary. Many of the losses occur at the beginning and end of this interval painting a picture of a two-phase extinction. Improved knowledge of the extinction has been supported by numerous geochemical studies that allow diverse proposed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timing shows regional variability. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) which lacks substantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the permian was likely Siberian Trap eruptions and their associated carbon dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from Siberian volcanism have also been linked to the crisis, but the short-term nature of these episodes(cades) and the overwhelming evidence for rapid warming during the crisis makes this an unlikely cause. Finally, whilst the extinction is well studied in equatorial latitudes, a different history is found in northern Boreal latitudes

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter

Experimental investigation of radiative heat propagation in a simplified generic packed bed

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particuology 2024年第5期88卷 149-160页

作者： Matthias Tyslik Lukas pörtner Siegmar Wirtz Martin Schiemann Institute of Energy plant Technology Ruhr-University Bochum44780 BochumGermany

A novel test rig for the investigation of radiative heat transfer in packed beds has been developed and is introduced with representative experimental *** individual components and the calibration are *** generic packed bed is realized in a simplified way by an arrangement of parallel rods,which represent particles in *** this arrangement,electrically heated rods provide the radiation propagating through the rod array to heat the passive counterparts.A sophisticated temperature-control scheme with a large number of thermocouples and infrared-imaging provides in-depth information about heat transfer in the *** radiation intensities are determined with a Fourier-transform infrared spectroscopy,which has been modified and validated for this specific *** order to compare the influence of different surface properties of particles on the heat propagation and surface reflections,rod samples made of stainless steel and magnesium oxide are *** influence of material properties becomes clearly visible by comparing the high radiation intensities resulting from a stainless steel rod array to the same geometry built from magnesium oxide *** addition,the influence of the surface properties is particularly evident in the infrared images since the reflections are significantly higher for the stainless steel samples than for the magnesium oxide *** experimental results in the current work demonstrate the ability of the test rig to provide data with a well-defined accuracy as a validation base for numerical radiation simulations in packed beds.

关键词： Thermal radiation Spectral reflections Fourier-transform infrared spectroscopy

Non-participation of asymptomatic candidates in screening protocols reduces early diagnosis and worsens prognosis of colorectal cancer

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World Journal of Gastroenterology 2024年第26期30卷 3198-3200页

作者： Sergio pérez-Holanda Office of Regional Viceministry of Health Regional Viceministry of HealthOviedo 33005AsturiasSpain

The Agatsuma et al’s study shows that despite the evidence of the benefits of an early colorectal cancer(cRc)diagnosis,through screening in asymptomatic subjects,up to 50%of candidates reject this option and many of those affected are diagnosed later,in advanced *** efficacy of screening programs has been well-established for several years,which reduces the risk of cRc morbidity and mortality,without taking into account the test used for screening,or other ***,a significant proportion of patients remain unscreened,so understanding the factors involved,as well as the barriers of the population to adherence is the first step to possibly modify the participation *** barriers could include a full range of social and political aspects,especially the type of financial provision of each health *** Japan,health services are universal,and this advantageous situation makes it easier for citizens to access to these services,contributing to the detection of various diseases,including ***,the symptomatic cRc group had a lower early-stage diagnosis rate than the patients detected during follow-up for other comorbidities,and symptomatic and cancer screening groups showed similar early-stage diagnosis.

关键词： colorectal neoplasms cancer registry Diagnostic route cancer screening Stage at diagnosis

Effect of Moringa oleifera on semen quality profiles in endangered Teressa goat under tropical humid island ecosystem

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Asian pacific Journal of Reproduction 2024年第2期13卷 89-96页

作者： p.perumal Jai Sunder A.K.De A.K.Nahak D.K.chaurasia T.c.Balamurugan D.Bhattacharya IcAR-central Island Agricultural Research Institute Port Blair-744105Andaman and Nicobar IslandsIndia OUAT-college of Veterinary Science and Animal Husbandry Bhubaneswar-751003OdishaIndia TANUVAS-Veterinary college and Research Institute Salem-636112Tamil NaduIndia

Objective:To investigate the effect of Moringa oleifera leaf extract on semen quality parameters in Teressa goat ***:A total of 25 semen samples from six bucks were selected for the *** of 150×10^(6) were incubated in 0,300,500 and 700μg of leaf extract as groupⅠ,Ⅱ,Ⅲ and Ⅳ,*** stored semen samples were analysed for motility,viability,total sperm abnormalities,plasma membrane,acrosomal and nuclear integrities,seminal plasma intracellular enzymes[aspartate aminotransferase(AST),alanine aminotransferase(ALT)and lactate dehydrogenase(LDH)]and total antioxidant capacity(TAc)and spermatozoa malondialdehyde(MDA)and cholesterol efflux in comparison with the control group(groupⅠ)for up to 72 ***:Moringa oleifera leaf extract(500μg/150×10^(6) spermatozoa)-treated semen had significantly higher motility,viability,plasma membrane,acrosomal and nuclear integrities,and TAc(pcantly lower total sperm abnormalities,AST,ALT,LDH,MDA production and cholesterol efflux compared to those in other Moringa oleifera leaf extract treated(300 or 700μg/150×10^(6) spermatozoa)and control groups at different hours of liquid storage(pparameters and TAc showed an increasing trend and total sperm abnormalities,MDA production,leakage of intra-cellular enzymes and cholesterol efflux showed a decreasing trend from group Ⅰto group Ⅲand then an opposite trend from group Ⅲ to group Ⅳ at different hours of liquid ***:Moringa oleifera leaf extract 500μg/150×10^(6) spermatozoa can be used for liquid semen preservation in Teressa goat at Andaman and Nicobar Islands.

关键词： Moringa oleifera Semen Teressa goat Andaman and Nicobar Islands