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Study of asphaltene reaggregation in toluene/heptane mixture by dynamic and static light scattering

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Petroleum Research 2024年第1期9卷 48-54页

作者： Vladimir n.Kuryakov Oil and Gas Research Institute of RAS(OGRI RAS) Gubkina Str.3119333MoscowRussian Federation

This paper presents the study of the effect of multiple ultrasonic impacts on submicron asphaltene aggregates in a toluene/heptane solution,conducted with dynamic light scattering *** objects of the study were four samples of asphaltenes obtained from four different *** all samples,the change in the average size of the asphaltene submicron aggregates with time was measured after the addition of a precipitant(heptane)to a solution of asphaltenes in toluene at an amount above the threshold *** aggregates formed in solution after the addition of the precipitant and were subjected to ultrasonic treatment,which led to the destruction of the asphaltene *** of destroyed asphaltenes was *** kinetics of this aggregation were similar to the kinetics of aggregation of asphaltenes after the addition of a *** iterations of asphaltene aggregate destruction in the sample led to a significant change in the kinetics of aggregation:the growth of aggregates slowed and stabilized at a size of approximately 200 nm and 30 nm for the different studied samples.

关键词： Asphaltenes Aggregation Sonication Dynamic light scattering Re-aggregation Colloidal stability Resins

Occurrence of Extreme Rainfall and Flood Risks in Yopougon, Abidjan, Southeast Côte d’Ivoire from 1971 to 2022

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American Journal of Climate Change 2024年第3期13卷 427-451页

作者： Kolotioloma Alama Coulibaly Pauline Agoh Dibi-Anoh Bi néné Jules Tah Hervé Anoh Kouadio Christophe n’da Serge Camille Ahilé Kouakou Bernard Djè daouda Konaté Geography Department Felix Houphouet-Boigny University Abidjan Cte dIvoire national Meteorological Service Socit dExploitation et de Dveloppement Aroportuaire Aronautique et Mtorologique Abidjan Cte dIvoire BRL Ingnierie-Cte dIvoire Abidjan Cte dIvoire Graduate School of Education Lesley University Cambridge MA USA

Yopougon, located in the western part of the Autonomous District of Abidjan, is the most heavily populated municipality in Côte d’Ivoire. However, this area is prone to floods and landslides during the rainy season. The study aims to assess recent flood risks in the municipality of Yopougon of the Autonomous District of Abidjan. To achieve this objective, the study analyzed two types of data: daily rainfall from 1971 to 2022 and parameters derived from a numerical Field and Altitude Model (nFAM). The study examined six rainfall parameters using statistical analysis and combined land use maps obtained from the nFAM of Yopougon. The results indicated that, in 67% of cases, extreme rainfall occurred mainly between week 3 of May and week 1 of July. The peak of extreme rainfall was observed in week 2 of June with 15% of cases. These are critical periods of flood risks in the Autonomous District of Abidjan, especially in Yopougon. In addition, there was variability of rainfall parameters in the Autonomous District of Abidjan. This was characterized by a drop of annual and seasonal rainfall, and an increase of numbers of rainy days. Flood risks in Yopougon are, therefore, due to the regular occurrence of rainy events. Recent floods in Yopougon were caused by normal rains ranging from 55 millimeters (mm) to 153 mm with a return period of less than five years. Abnormal heavy rains of a case study on June 20-21, 2022 in Yopougon were detected by outputs global climate models. Areas of very high risk of flood covered 18% of Yopougon, while 31% were at high risk. Climate information from this study can assist authorities to take in advance adaptation and management measures.

关键词： Yopougon-Abidjan Extreme Rainfall Rainy day Return Period Flood Risk Areas

U-Pb dating of bastnäsite from the Vuoriyarvi massif:An example application for assessing the REE potential of carbonatite-related deposits

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Geoscience Frontiers 2024年第5期15卷 444-453页

作者： Evgeniy n.Kozlov Ekaterina n.Fomina Qiuli Li Jiao Li Geological Institute Kola Science Centre of the Russian Academy of SciencesApatity 184209Russia Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China

The Vuoriyarvi massif is a Devonian multistage alkaline-ultrabasic carbonatite complex within the Kola alkaline *** carbonatites of the Vuoriyarvi massif contain abundant rare-earth mineralization mainly represented by ancylite-(Ce)and bastnäsite-(Ce).Ancylite was previously shown to have probably formed in the Devonian(ca.365 Ma)during an early postmagmatic *** geological observations have revealed a much later crystallization of bastnäsite but have not been able to specify the exact age of the *** in situ U-Pb dating of bastnäsite allowed us to constrain its ***äsite for this study was extracted from two varieties of dolomite carbonatite breccias cemented by(1)quartz-bastnäsite and(2)strontianite aggregates(hereafter bastnäsite-rich and strontianite-rich carbonatites–BRC and SRC,respectively).The obtained age estimations(237.7±9.8 Ma and 239.9±4.1 Ma,respectively)indicate that both studied rocks were formed during a single *** revealed age difference(~125 Ma)excludes the genetic link between the bastnäsite origin and regional alkaline magmatism,pointing out an additional source for the Vuoriyarvi bastnäsite-bearing ***,the obtained U-Pb ages provide strong evidence that a Triassic event is responsible for the occurrence of bastnäsite mineralization due to hydrothermal REE redistribution from the Devonian ancylite-rich *** of the REEs released during this process via dissolution of ancylite were precipitated in situ as bastnäsite,while strontium was transported and incorporated into *** Pb isotopic characteristics of bastnäsite(^(206)Pb/^(204)Pb=18.1±0.1,^(207)Pb/^(204)Pb=15.3±0.1,and^(207)Pb/^(206)Pb=0.84±0.01)are most probably inherited from the Devonian host rocks of the Vuoriyarvi massif involved in the Triassic *** signatures of Pb,Sr,and nd show that the depleted mantle and lower crust played the leading role in formation of the Vuoriyarvi alkaline

关键词： Bastnäsite REE Carbonatites U-Pb dating Vuoriyarvi Kola alkaline province

Heterosis effect for larval performance of fall armyworm interstrain hybrids

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Insect Science 2024年第4期31卷 1296-1312页

作者： Laijiao Lan nicolas nègre DGIMI University of MontpellierINRAEMontpellierFrance

Spodoptera frugiperda,also known as fall armyworm(FAW),is an invasive crop pest that can feed on a variety of host plants,posing a serious threat to food *** are two sympatric strains of FAW that are morphologically identical but described with different food preferences:the“rice strain”(SfR)and the“corn strain”(SfC).A few genetic loci exist to identify these two *** and Z-chromosome-linked haplotypes are the most used,but the biggest part of the genome displays little polymorphism between strains that could explain their adaptation to different *** have previously observed consistent transcription differences between the strains in both laboratory and natural ***,we wonder if there are effects from host-strain-associated loci,maternally or paternally inherited,on FAW performance that could explain the divergence between the two FAW *** test this hypothesis,we first produced two F1 hybrid generations(SfR♀×SfC♂,SfC♀×SfR♂).These reciprocal hybrids should be heterozygous for all chromosomes except for the maternally inherited mitochondrial and sexual W *** evaluate whether plant preference is determined by these genetic loci,we cultivated the two hybrids and the two parental strains in triplicate on an artificial diet and recorded several phenotypic traits such as weight over time,survival rate,emerging rate,developmental time,and sex ***,the same performance experiment was carried out on corn ***,on the artificial diet,the two hybrid genotypes were both more performant than the two parental strains in terms of survival rate,pupal emerging rate,and developmental time,whereas they were intermediate to the inbred parental strains in pupal *** the corn plant diet,both hybrid genotypes outperformed the two parental strains in larval *** these asymmetrical results revealed that mitochondrial or sex-linked haplotypes alone cannot explain the performance differences

关键词： fall armyworm Haldane's rule heterosis hybrid performance mitochondria

Human leukocyte antigen compatibility and incidence of donorspecific antibodies in pediatric liver transplant recipients

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World Journal of Gastroenterology 2024年第33期30卷 3837-3845页

作者： Melina U Melere Flavia H Feier Jorge neumann Antônio n Kalil Juliana de M Montagner Luiza S nader Carolina S da Silva Marco Aurélio F Junior Gabriela P Coral Guilherme P Bobsin Cristina T Ferreira Department of Hepatology and Liver Transplantation Santa Casa de Porto AlegrePorto Alegre 90050170Rio Grande do SulBrazil Department of Hepato-biliary-pancreatic Surgery and Liver Transplantation Irmandade Santa Casa de Misericórdia de Porto AlegrePorto Alegre 90020-090Rio Grande do SulBrazil Postgraduation Program in Medicine:Hepatology Federal University of Health Sciences of Porto AlegrePorto Alegre 90050-170Rio Grande do SulBrazil Laboratory of Transplantation Immunology Irmandade Santa Casa de Misericórdia de Porto AlegrePorto Alegre 90020-090Rio Grande do SulBrazil

BACKGROUnD Antibody-mediated rejection following liver transplantation(LT)has been increasingly recognized,particularly with respect to the emergence of de novo donor-specific antibodies(DSAs)and their impact on graft *** substantial evidence for adult populations exists,research focusing on pediatric LT outcomes remains *** To investigate the prevalence of human leukocyte antigen(HLA)mismatches and DSA and evaluate their association with rejection episodes after pediatric *** A cohort of pediatric LT recipients underwent HLA testing at Santa Casa de Porto Alegre,Brazil,between December 2013 and December *** patients who survived for>30 days after LT with at least one DSA analysis were *** classes I and II and cross-matches were *** presence of de novo DSA(dnDSA)was evaluated at least 3 months after LT using the Luminex®single antigen bead method,with a positive reaction threshold set at 1000 *** episodes were confirmed by liver *** Overall,67 transplanted children were analyzed;61 received grafts from living donors,85%of whom were related to ***-transplant DSA(class I or II)was detected in 28.3%of patients,and dnDSA was detected in 48.4%.The median time to DSA detection after LT was 19.7[interquartile range(IQR):4.3-35.6]*** rejection occurred in 13 patients at follow-up,with C4d positivity observed in 5/13 Liver *** median time to rejection was 7.8(IQR:5.7-12.8)*** presence of dnDSA was significantly associated with rejection(36%vs 3%,Pn-free survival rates at 12 and 24 months were 76%vs 100%and 58%vs 95%for patients with dnDSA anti-DQ vs those without,*** Our findings highlight the importance of incorporating DSA assessment into pre-and post-transplantation protocols for pediatric LT *** implications may include immunosuppression minimization strategies based on this analysis in pediatric LT recip

关键词： Human leukocyte antigens Donor-specific antibodies Liver transplantation Pediatric Rejection

RBC aggregation,deformation and adhesion to endothelium:Role of nitric oxide derived from L-Arginine and sodium nitroprusside

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Journal of Innovative Optical Health Sciences 2024年第5期17卷 53-65页

作者： M.K.Maksimov P.B.Ermolinskiy O.n.Scheglovitova n.n.Sklyankina A.V.Muravyov A.E.Lugovtsov A.V.Priezzhev Faculty of Physics M.V.Lomonosov Moscow State University bld.1subbuilding.2Leninskie goryMoscow 11991Russia n.F.Gamaleya national Research Center for Epidemiology and Microbiology 18 Gamaleya StreetMoscow 123098Russia K.D.Ushinsky Yaroslavl State Pedagogical University 108/1 Respublikanskaya StreetYaroslavl 150000Russia

Red blood cells(RBCs)are the most abundant human blood *** aggregation and deformation strongly determine blood viscosity which impacts hemorheology and *** turn,RBC properties depend on di®erent endogenous and exogenous *** such factor is nitric oxide(nO),which is mainly produced by endothelial cells(EC)from L-arginine amino acid in the circulatory *** the mechanisms of the RBC-endothelium interplay are not clear up to date and considering its possible clinical importance,the aims of this study are to investigate in vitro:(1)The e®ect of L-arginine induced nO on RBC aggregation and adhesion to endothelium;(2)the nO e®ect on RBC aggregation and deformation induced by L-arginine and sodium nitroprusside without the presence of endothelium in the *** RBC aggregation and adhesion to a monolayer of EC were studied using optical tweezers(OT).The RBC deformability and aggregation without endothelium in the samples were studied using the°ow chamber method and Myrenne *** con¯rmed that nO increases deformability and decreases aggregation of *** showed that the soluble guanylate cyclase pathway appears to be the only nO signaling pathway *** the samples with the endothelium,the\bell-shaped"dependence of RBC aggregation force on L-arginine concentration was observed,which improves our knowledge about the process of nO production by ***,data related to L-arginine accumulation by endothelium were obtained:necessity of the presence of extracellular L-arginine stated by other authors was put under *** our study,nO decreased the RBC-endothelium adhesion,however,the tendency appeared to be weak and was not con¯rmed in another set of *** our knowledge,this is the¯rst attempt to measure the forces of RBC adhesion to endothelium monolayer with OT.

关键词： Red blood cells aggregation L-arginine endothelium optical tweezers Myrenne flow chamber

A FLEXIBLE OBJECTIVE-COnSTRAInT APPROACH AnD A nEW ALGORITHM FOR COnSTRUCTInG THE PARETO FROnT OF MULTIOBJECTIVE OPTIMIZATIOn PROBLEMS

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Acta Mathematica Scientia 2024年第2期44卷 702-720页

作者： n.HOSEInPOOR M.GHAZnAVI Faculty of Mathematical Sciences Shahrood University of TechnologyShahroodIran

In this article, a novel scalarization technique, called the improved objective-constraint approach, is introduced to find efficient solutions of a given multiobjective programming problem. The presented scalarized problem extends the objective-constraint problem. It is demonstrated that how adding variables to the scalarized problem, can lead to find conditions for (weakly, properly) Pareto optimal solutions. Applying the obtained necessary and sufficient conditions, two algorithms for generating the Pareto front approximation of bi-objective and three-objective programming problems are designed. These algorithms are easy to implement and can achieve an even approximation of (weakly, properly) Pareto optimal solutions. These algorithms can be generalized for optimization problems with more than three criterion functions, too. The effectiveness and capability of the algorithms are demonstrated in test problems.

关键词： multiobjective optimization Pareto front scalarization objective-constraint approach proper efficient solution

Enhancing nitrogen removal in constructed wetlands: The role of influent substrate concentrations in integrated vertical-flow systems

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Environmental Science and Ecotechnology 2024年第5期21卷 103-112页

作者： Tongtong Liu da Li Yan Tian Jiajie Zhou Ye Qiu Dongyi Li Guohong Liu Yujie Feng State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyNo.73 Huanghe RoadNangang DistrictHarbin 150090China Institute of Chemical Engineering in Heilongjiang Province 3#Nanhu loadHigh Tech R&D Zone of Harbin CityHarbin 150028China

Recent advancements in constructed wetlands(CWs)have highlighted the imperative of enhancing nitrogen(n)removal ***,the variability in influent substrate concentrations presents a challenge in optimizing n removal strategies due to its impact on removal efficiency and *** we show the interplay between influent substrate concentration and n removal processes within integrated vertical-flow constructed wetlands(IVFCWs),using wastewaters enriched with nO_(3)^(-)-n and nH4þ-n at varying carbon to nitrogen(C/n)ratios(1,3,and 6).In the nO_(3)^(-)-n enriched systems,a positive correlation was observed between the C/n ratio and total nitrogen(Tn)removal efficiency,which markedly increased from 13.46±2.23%to 87.00±2.37%as the C/n ratio escalated from 1 to ***,in nH4þ-n enriched systems,Tn removal efficiencies in the A-6 setup(33.69±4.83%)were marginally 1.25 to 1.29 times higher than those in A-3 and A-1 systems,attributed to constraints in dissolved oxygen(DO)levels and *** community analysis and metabolic pathway assessment revealed that anaerobic denitrification,microbial n assimilation,and dissimilatory nitrate reduction to ammonium(DnRA)predominated in nO_(3)^(-)-n systems with higher C/n ratios(C/n 3).In contrast,aerobic denitrification and microbial n assimilation were the primary pathways in nH4þ-n systems and low C/n nO_(3)^(-)-n systems.A mass balance approach indicated denitrification and microbial n assimilation contributed 4.12-47.12%and 8.51e38.96%in nO_(3)^(-)-n systems,respectively,and 0.55e17.35%and 7.83e33.55%in nH4þ-n systems to Tn *** enhance n removal,strategies for nO_(3)-n dominated systems should address carbon source limitations and electron competition between denitrification and DnRA processes,while nH4þ-n dominated systems require optimization of carbon utilization pathways,and ensuring adequate DO and alkalinity supply.

关键词： Constructed wetland nitrogen removal pathway Denitrification Microbial nitrogen assimilation Enhanced strategy

Proximity to corridors benefits bird communities in vegetated interrow vineyards in Mendoza, Argentina

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Avian Research 2024年第2期15卷 147-155页

作者： Andrea Paula Goijman Agustín Zarco EEA La Consulta Instituto Nacional de Tecnología Agropecuaria(INTA)San CarlosMendozaArgentina Instituto Argentino de Investigacion en las Zonas Aridas(IADIZA)COnICET 5500MendozaArgentina

Management under ecological schemes and increasing habitat heterogeneity,are essential for enhancing biodiversity in *** provide several contributions to agriculture,for example pest control,recreation and enhancing human mental health,and have intrinsic *** are also ideal model organisms because they are easy to survey,and species respond differently to agricultural land use at different *** borders of crops are key for many species of birds,and distance to the border have been found to be an important factor in vineyard-dominated *** evaluate if there are differences in the bird assemblage,between the interior compared to borders within vineyards,using a hierarchical community occupancy *** hypoth-esized that occupancy of birds is greater in environments with greater heterogeneity,which in this study was considered to be contributed by the proximity to vegetated *** expected that vineyard borders close to corridors will have higher bird occupancy than the center of the *** research was conducted in three vineyards with biodiversity-friendly management practices,in Gualtallary,Mendoza,*** surveys were conducted over three breeding seasons from 2018 to *** and richness of the bird community was more closely associated with the borders adjacent to the corridors than with the interior of the vineyards,as we initially predicted,although the assemblage of birds did not differ *** than 75%of the registered species consume exclusively or partially ***-friendly management and ecological schemes,together with vegetated corridors provide multiple benefits for biodiversity *** ap-proaches not only minimize the use of agrochemicals but also prioritize soil cover with spontaneous vegetation,which supports a diverse community of insectivorous bird species,potentially contributing to pest control.

关键词： Avian Bayesian analysis Field scale agroecosystem Management Multi-species occupancy model nature’s contributions to people