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Solid-liquid extraction for yttrium recovery using porous polymeric resin（XAD-7） functionalized with D2EHpA

Journal of Rare Earths 2024年第9期42卷 1764-1773页

作者： p.A.martínez-montoya R.G.Sanchez-Alvarado D.Y.medina-Velazquez m.l.ca.rera.jota.p.ga.nica.ch.vez A.de J.morales-Ramirez Higher School of chemical Engineering and Extractive Industries ESIQIEIPNDepartment of Metallurgical Engineering metropolitan Autonomous University Department of MaterialsBasic Sciences and Engineering Center for Research and Technological Innovation CIITECIPN

The recovery of yttrium is proposed by applying a solid-liquid extraction process using di-2-ethyl hexylphosphoric acid（D2EHpA） as extracting *** extracting agents were supported on a macro porous polymeric resin XAD-7（solid phase）.Yttrium ions extraction and discharge tests were performed,firstly from a synthetic aqueous solution of 100 mg/l Y（liquid phase） at 25℃ with *** effects of pH of aqueous solutions bearing yttrium,volume fraction of extracting agents and the solid/liquid（S/l）ratio on the yttrium recovery were *** most favorable conditions for yttrium ions extraction are;20 vol% D2EHpA functionalized resin,pH=1.5 and an S/l ratio of 10 mg/ml The discharge of yttrium ions was done under the same conditions of extraction stage,using a 2 mol/l [H2SO4] as stripping *** to 80% yttrium is extracted,while 75% yttrium is recovered in the striping *** all experiments,the reaction equilibrium is reached after 20 min,and the kinetics for the extraction stage was determined as a second-order ***,experiments were carried out to discharge the yttriumloaded resins,and it has been determined that the best pH value to strip the Y ions is *** tests of extraction and discharge for yttrium ions show that the functionalized resin can work at least five cycles without decreasing its ***,the proposed process was tested in a real solution with Y ions fro m a waste fluorescent la mp powder leached in H2SO4,demonstrating the ability to effectively recover yttrium,separating it from various metals from the studied residue.

关键词： Fluorescent lamps recycling Rare earth solid-liquid extraction Solid-liquid kinetics extraction XAD-7 resin Yttrium recovery

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Boron-containing compounds as labels,drugs,and theranostic agents for diabetes and its complications

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World Journal of Diabetes 2024年第6期15卷 1060-1069页

作者： marvin A Soriano-Ursúa R Ivan Cordova-chávez Eunice D Farfan-garcía George Kabalka Department of physiology Escuela Superior de MedicinaInstituto Politécnico NacionalCiudad de México 11340Mexico Department of physiology Instituto Politécnico NacionalMexico City 11340Mexico Department of Biochemistry Instituto Politécnico NacionalMexico City 11340Mexico Department of chemistry The University of TennesseeKnoxvilleTN 37996United States

Diabetes is a disease with a high global *** strategies have failed to limit the advancement and impact of the *** early diagnosis and treatment will require the development of new *** this sense,boroncontaining compounds have been reported as agents with the ability to reduce glycemia and *** have also been used for labeling and measuring carbohydrates and other molecules linked to the initial stages of diabetes and its *** addition,certain boron compounds bind to molecules related to diabetes development and their biological activity in the regulation of elevated ***,it should be noted that some boron compounds appear to exert beneficial effects on diabetes complications such as accelerating wound healing while ameliorating pain in diabetic patients.

关键词： Boron carbohydrates metabolism Diabetes Boronodipyrromethene

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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

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Standardizing mI-TlIF, a proposal for a Reproducible Technique

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Open Journal of modern Neurosurgery 2024年第2期14卷 91-103页

作者： Iván Ulises Sámano lópez Jesús Alberto pérez Contreras Emmanuel cantú chávez Diana chávez lizárraga Ana Sofía peña Blesa Thania Karina Gutiérrez Anchondo Á ngeles Pedregal Ciudad de México México

Background: minimally invasive transforaminal lumbar interbody fusion (mI TlIF) is a widely known and performed technique, however its versatility among different physicians continues to hinder its replication and results. Therefore, this study aimed to provide a step-by-step surgical guide to perform a safe mI-TlIF, based on the results obtained in patients operated on by a single surgeon over a period of 12 years. patients and methods: A retrospective, single center, longitudinal, and observational cohort study was conducted with 931 patients who underwent mI TlIF by a single surgeon between 2010 and 2022 using the technique described on this paper, each with a minimum follow-up of 12 months. Criteria included Schizas classification, listhesis according to meyerding classification, number of levels treated, cage size, and complications (screw repositioning or cerebrospinal fluid leak). patient clinical outcomes were assessed using the Oswestry Disability Index (ODI), Visual Analog Scale (VAS) for pre- and postoperative radicular pain. Thin slice CT scans were used to assess the progression of the fusion using the Bridwell classification. In the statistical analysis, percentages, median, and interquartile range (IQR) were calculated. Results: Nine hundred and thirty one patients underwent mI TlIF using the technique described, eight hundred and eighty (94.5%) had a single level treated and fifty one (5.5%) had a 2 level procedure (982 levels), an 8mm cage was placed on five hundred and seventeenlevels (52.7%), six hundred and sixty three levels(67.6%) achieved grade I fusion, two hundred and sixty six levels (27.1%) achieved grade II fusion, 52 levels (5.3) achieved grade III fusion and one level (0.1) achieved a grade IV fusion or non-union. Revision surgery was performed on 3 patients (0.3%) for screw repositioning, cerebrospinal fluid leak was present on 2 patients during surgery and treated before closure. VAS scores and ODI were improved at 12 months postop (V

关键词： mITlIF lumbar Interbody Fusion Technique pain Relief and Disability

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Academic Stress Assessment Using Virtual Reality as an Educational Tool in Spine Surgery

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Open Journal of modern Neurosurgery 2024年第2期14卷 114-123页

作者： Diana chávez lizárraga Jesús Alberto pérez Contreras Fernando Alvarado Gómez Evelyn Quintero medina Emmanuel cantú chávez Iván Ulises Sámano lópez Ana Sofía peña Blesa Department of Neurosurgery ángeles Pedregal Ciudad de México México Department of Traumatology and Orthopedics Hospital Santa Fe Bogotá Colombia

Introduction: The evaluation of academic stress in medical students and residents is a topic of significant interest, given the considerable challenges they face during their learning process with traditional teaching methods. The use of technologies like virtual reality presents an opportunity to enhance their skills through simulations and training. The main objective of this study is to qualitatively assess the stress levels experienced by medical students and residents by integrating virtual reality into their current learning methods, aiming to improve their ability to manage stressors in their practice. material and methods: A questionnaire was conducted with 12 medical students and 12 Traumatology and orthopedics residents. The purpose of the questionnaire was to evaluate the levels of academic stress using the SISCO inventory. The stress levels were calculated by transforming average values into percentages, and the following criteria were assigned: 0 to 33% for mild Stress, 34 to 66% for moderate Stress, and 67 to 100% for Deep Stress. Then, a virtual reality class focused on spine surgery was provided. Both medical students and residents were trained using the Non Nocere SharpSurgeon software platform and Oculus Quest 2 virtual reality glasses. At the end of the session, a second questionnaire related to the practice with virtual reality was conducted with the same evaluation criteria and a comparative analysis was carried out. Results: 12 undergraduate students from Hospital Angeles mexico, CDmX and 12 traumatology and orthopedics residents at Hospital Santa Fe, Bogota were evaluated. The students in CDmX reported an average qualitative stress of 28.50% during habitual practices, which decreased to an average of 14.67% after virtual reality practice. Residents in Bogotá experienced an average qualitative stress of 30.50% with their current learning methods but this reduced to an average of 13.92% after using virtual reality. These findings indicate that t

关键词： Virtual Reality Academic Stress learning Strategies Spine Surgery Training

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自推进胶囊在小肠中移动时的优化控制

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机械工程学报 2024年

作者：廖茂林李智朱佳鹏王泽旭 JOSEpHpáez chávez 北京科技大学机械工程学院北京科技大学井下智能控制研究院德累斯顿工业大学动力学研究中心

在消化道检测领域，传统的管线式内镜常给患者带来极大的心理负担与生理不适，胶囊内镜则因驱动方式和控制复杂等原因而难以对小肠部位开展全面而高效的检测。为此，考虑以双边约束的激振胶囊为研究对象，根据小肠结构的变化分别建立了... 详细信息

在消化道检测领域，传统的管线式内镜常给患者带来极大的心理负担与生理不适，胶囊内镜则因驱动方式和控制复杂等原因而难以对小肠部位开展全面而高效的检测。为此，考虑以双边约束的激振胶囊为研究对象，根据小肠结构的变化分别建立了扩张段和狭窄段的小肠-胶囊耦合动力学模型，并以小肠多变的摩擦环境以及对胶囊的包裹程度不同作为不稳定因素，分析了自推进胶囊的动力学行为规律。基于此，同时以胶囊的移动速度、单位能耗和对小肠壁冲击力作为优化目标，采用(Six-Sigma+NSga-II+monte-carlo)组合优化算法获取胶囊可控移动对应的参数组合区间。最终，结合ADAmS动力学仿真与实验测试验证了当采用优化后的参数组合控制自推进胶囊时，可使其实现低能耗低冲击的定速定向移动。

关键词：小肠胶囊非光滑多目标优化运动控制

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pollen analysis reveals the effects of uncovered interactions,pollen-carrying structures,and pollinator sex on the structure of wild bee-plant networks

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Insect Science 2024年第3期31卷 971-988页

作者： Clément Tourbez carmelo Gómez-martínez miguelÁngel Gonzalez-Estévez Amparo lazaro mediterranean Institute for Advanced Studies(UIB-CSIC) Global Change Research GroupEsporlesBalearic IslandsSpain Department of Biology Ecology AreaUniversity of the Balearic/slandsPalmaSpain

pollination networks are increasingly used to model the complexity of interactions between pollinators and flowering plants in *** methods exist to sample these interactions,with direct observations of plant-pollinator contacts in the field being by far the most *** the identification of pollen carried by pollinators allows uncovering interactions and increasing sample sizes,the methods used to build pollen-transport networks are variable and their effect on network structure remains *** understand how interaction sampling influences the structure of networks,we analyzed the pollen found on wild bees from eight communities across mallorca Island and investigated the differences in pollen loads between bee body parts(scopa ***)and *** then assessed how these differences,as well as the uncovered interactions not detected in the field,influenced the structure of wild bee-plant *** identified a higher quantity and diversity of pollen in the scopa than in the rest of the female body,but these differences did not lead to differences in structure between plant-pollination(excluding scopa pollen)and bee-feeding interaction(including scopa pollen)***,networks built with pollen data were richer in plant species and interactions and showed lower modularity and specialization(H2'),and higher nestedness than visitation networks based on field *** interactions with plants were stronger compared to those of males,although not ***,females were more generalist(low d')and tended to be more central in interaction networks,indicating their more key role structuring pollination networks in comparison to *** study highlights the importance of palynological data to increase the resolution of networks,as well as to understand important ecological questions such as the differences between plant-pollination and bee-feeding interaction networks,and the role of sexes in pollination.

关键词： palynology pollen-transport networks pollination role of bee sexes sampling methodology visitation networks

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乡村公共数字文化服务标准化推进机理

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图书情报研究 2024年第2期17卷 26-38页

作者：田一王锰连忻杰 Amalia Isabel Rivero chávez 江苏大学科技信息研究所镇江212013 曼萨尼约市历史档案馆古巴曼萨尼约市87510

[目的/意义]乡村公共数字文化服务在国家层面已然得到政策和法律保障,基本公共文化服务体系初具成效。本研究聚焦乡村公共数字文化服务标准化。[方法/过程]以我国三个公共文化服务体系示范区乡镇服务点的实地调研数据为依据,深入了解乡... 详细信息

[目的/意义]乡村公共数字文化服务在国家层面已然得到政策和法律保障,基本公共文化服务体系初具成效。本研究聚焦乡村公共数字文化服务标准化。[方法/过程]以我国三个公共文化服务体系示范区乡镇服务点的实地调研数据为依据,深入了解乡村公共数字文化服务标准化状况。[结果/结论]从推进主体、推进内容、推进方式三方面构建乡村公共数字文化服务标准化机制的模型,“政府驱动型”、“服务增效型”、“基础保障型”的三重应用模式为政府以标准化完善现代化公共文化服务体系提供了有效参考。

关键词：公共数字文化服务数字乡村服务标准扎根理论

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Differential Expression of Genes Related to Fruit Development and capsaicinoids Synthesis in Habanero pepper plants Grown in Contrasting Soil Types

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phyton-International Journal of Experimental Botany 2024年第2期93卷 151-183页

作者： Eduardo Burgos-Valencia Federico garcía-laynes Ileana Echevarría-machado Fatima medina-lara miriam monforte-González JoséNarváez-Zapata manuel martínez-Estévez Unidad de Bioquímica y Biología molecular de plantas Centro de Investigación Científica de YucatánCalle 43#130Chuburnáde HidalgoMéridaYucatán97205México Instituto politécnico Nacional-Centro de Biotecnología Genómica Blvd Del Maestro esq.Elias PiñaReynosaTamaulipas88710México

Habanero pepper(capsicum chinense Jacq.)is a crop of economic relevance in the peninsula of *** fruits have a high level of capsaicinoids compared to peppers grown in other regions of the world,which gives them industrial *** is an important factor that affects pepper development,nutritional quality,and capsaicinoid ***,the effect of soil type on fruit development and capsaicinoid metabolism has been little *** work aimed to compare the effect of soils with contrasting characteristics,black soil(BS)and red soil(RS),on the expression of genes related to the development of fruits,and capsaicinoid synthesis using a transcriptomic analysis of the habanero pepper *** growing in RS had bigger fruits and higher expression of genes related to floral development,fruit abscission,and softening which suggests that RS stimulates fruit development from early stages until maturation *** from plants growing in BS had enrichment in metabolic pathways related to growth,sugars,and ***,these fruits had higher capsaicinoid accumulation at 25 days post-anthesis,and higher expression of genes related to the branched-chain amino acids metabolism(ketol-acid reductisomerase KARI),pentose phosphate pathway and production of NADpH(glucose-6-phosphate-1-dehydrogenase G6pDH),and proteasome and vesicular traffic in cells(26S proteasome regulatory subunit T4 RpT4),which suggest that BS is better in the early stimulation of pathways related to the nutritional quality and capsaicinoid metabolism in the fruits.

关键词： capsicum chinense jacq soil types plant growth environmental conditions fruit quality capsaicinoid metabolism transcriptome

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A Hybrid model Evaluation Based on pca Regression Schemes Applied to Seasonal precipitation Forecast

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Atmospheric and Climate Sciences 2024年第3期14卷 328-353页

作者： pedro m. González-Jardines Aleida Rosquete-Estévez maibys Sierra-lorenzo Arnoldo Bezanilla-morlot Center for Atmospheric physics Institute of Meteorology Havana Cuba

possible changes in the structure and seasonal variability of the subtropical ridge may lead to changes in the rainfall’s variability modes over caribbean region. This generates additional difficulties around water resource planning, therefore, obtaining seasonal prediction models that allow these variations to be characterized in detail, it’s a concern, specially for island states. This research proposes the construction of statistical-dynamic models based on pca regression methods. It is used as predictand the monthly precipitation accumulated, while the predictors (6) are extracted from the ECmWF-SEAS5 ensemble mean forecasts with a lag of one month with respect to the target month. In the construction of the models, two sequential training schemes are evaluated, obtaining that only the shorter preserves the seasonal characteristics of the predictand. The evaluation metrics used, where cell-point and dichotomous methodologies are combined, suggest that the predictors related to sea surface temperatures do not adequately represent the seasonal variability of the predictand, however, others such as the temperature at 850 hpa and the Outgoing longwave Radiation are represented with a good approximation regardless of the model chosen. In this sense, the models built with the nearest neighbor methodology were the most efficient. Using the individual models with the best results, an ensemble is built that allows improving the individual skill of the models selected as members by correcting the underestimation of precipitation in the dynamic model during the wet season, although problems of overestimation persist for thresholds lower than 50 mm.

关键词： Seasonal Forecast principal Component Regression Statistical-Dynamic models

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