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小型质子转移反应质谱仪离子源的设计与优化

分析试验室 2024年第6期43卷 819-827页

作者：陈蹇平王俊闻路红陈腊宁波大学宁波高等技术研究院宁波315211 宁波华仪宁创智能科技有限公司宁波315100 广州市华粤行仪器有限公司广州511400

作为一种快速、高灵敏的挥发性有机物(vOCs)检测技术,质子转移反应质谱(PTR-MS)被越来越多地应用于环境、医学、公共安全等领域。作为PTR-MS的关键部件之一,空心阴极辉光放电离子源对仪器性能具有重要影响。本文通过有限元仿真优化了空... 详细信息

作为一种快速、高灵敏的挥发性有机物(vOCs)检测技术,质子转移反应质谱(PTR-MS)被越来越多地应用于环境、医学、公共安全等领域。作为PTR-MS的关键部件之一,空心阴极辉光放电离子源对仪器性能具有重要影响。本文通过有限元仿真优化了空心阴极结构,在阴极内径为20 mm、阳极与阴极间隙为4 mm时,离子源放电效果较好。将优化后的空心阴极辉光放电离子源与便携式质谱仪联用,并测试了离子信号与放电气压和放电电流的关系。结果表明,最佳放电气压约为200 Pa,最佳放电电流为9~13 m A。采用乙腈样品测试了仪器性能,系统响应时间在10 s以内,乙腈检出限约为10^(-9)(v/v),线性范围为50×10^(-9)~350×10^(-9)(v/v),线性相关系数R^(2)=0.991。利用该装置检测了苹果发酵过程中产生的vOCs随时间的变化,证明了该仪器可用于实际样品检测。

关键词：质子转移反应质谱空心阴极辉光放电离子源挥发性有机物线性离子阱有限元仿真

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Current Zoology 2024年第1期70卷 1-12页

作者： Lucia v.Sommaro Juan J.Martinez Marina B.Chiappero Andrea R.Steinmann Cristina N.gardenal JoséW.Priotto laboratorio de Ecologia Evolutiva y Biogeografia Instituto de Ecorregiones Andinas(INECoA)Universidad Nacional de Jujuy-Consejo Nacional de Investigaciones Cientificas y Tecnicas(CONICET)San Salvador de JujuyJujuyArgentina Instituto de Diversidad y Ecologia Animal(IDEA) Consejo Nacional de Investigaciones Cientificas y Técnicas(CONICET)and Universidad Nacionalde CordobaCordobaArgentina Catedra de genética de Poblaciones y Evolucion Facultad de Ciencias ExactasFisicas y NaturalesUniversidad Nacional de CordobaCordobaArgentina grupo de Investigaciones en Ecologia Poblacional y Comportamental(gIEPCO) Instituto de Ciencias de la TierraBiodiversidad y Ambiente(ICBiA)Universidad Nacional de Rio Cuarto-Consejo Nacional de Investigaciones Cientificas y Técnicas(CONICET)Rio CuartoCordobaArgentina

The sex-biased dispersal and kinship dynamics are important factors shaping the spatial distribution of individuals and are key parameters affecting a variety of ecological and evolutionary ***,we studied the spatial distribution of related individuals within a population of corn mice Calomys musculinus in a seasonal cycle to infer dispersal *** sampling was carried out from spring 2005 to winter 2006 in field borders of intensively managed *** data from 346 individuals with 9 microsatellites showed spatial genetic structure was weak for males,but not for *** results indicate a complex spatial kinship dynamic of related females across all ***,contrary to our expectations,dispersal distances decrease with the increase of the population ***,male dispersal distances were greater when population abundance increased and thus the availability of active *** disperse greater distances to mate and sire offspring with distant females as a possible inbreeding avoidance *** study shows that *** is capable of much greater scattering distances than previously reported and that dispersal occurs fluidly and without barriers across the *** indirect benefit of dispersal on individual fitness could be related to relaxing the competition in the natal area and increasing the mating *** study highlights the value of combining genetic relatedness,fieldwork observations,and behavioral data to estimate dispersal at a fine geographical scale.

关键词： dispersal distances kinship dynamics microsatellite small mammals spatial autocorrelation

Ductal carcinoma in situ within a fibroadenoma:A case report and review of literature

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World Journal of Radiology 2024年第3期16卷 58-68页

作者： Yazmin Olivares-Antúnez Yesika Janett Dávila-Zablah JoséRaúl vázquez-Ávila gabriela Sofía gómez-Macías María Teresa Mireles-Aguilar Margarita Lilia garza-Montemayor Department of Diagnostic Breast Imaging Center Hospital Zambrano HellionTecnológico de MonterreyNuevo León 66260Mexico Department of Patology Service Hospital San JoséTecnológico de MonterreyNuevo León 64710Mexico Department of Faculty of Medicine Hospital Universitario de la UANLNuevo León 64710Mexico. Department of Breast Surgery Center Hospital Zambrano HellionTecnológico de MonterreyNuevo León 66260Mexico

BACKgROUND Fibroadenoma(FA)is the most common tumor found in young women,although it can occur in any age *** carcinoma in situ(DCIS)that is confined in a FA is rare;it is most frequently reported as an incidental *** SUMMARY We report a case of DCIS within a FA in a 46-year-old female without cancerrelated personal and family *** patient was diagnosed with a breast conglomerate of nodules and was followed for 1 *** the current control image study,we found suspicious microcalcification,as a new finding,within one of the ***,a core biopsy of the tumor,which appeared hypoechoic,oval,and circumscribed,was *** pathological diagnosis was ductal carcinoma in situ within a fibroepithelial *** patient underwent breastconserving surgery and received radiotherapy as well as endocrine therapy(tamoxifen).CONCLUSION We recommend a multidisciplinary approach for adequate treatment and followup.

关键词： Carcinoma in situ Fibroadenoma Mammography Ultrasound Magnetic resonance imaging Radiology Case report

Survival of some food-borne bacteria in kefir produced by microbial levan and pullulan

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Food Bioscience 2022年第3期47卷 1082-1089页

作者： gökhan gurur gökmen Jaroslaw Kowalik Duygu Kışla Department of Food Engineering Faculty of EngineeringEge University35100BornovaIzmirTurkey Department of Dairy Science and Quality Management Faculty of Food SciencesUniversity of Warmia and Mazury in OlsztynOczapowskiego str.710-719OlsztynPoland

Kefir is a fermented milk product produced by kefir grains traditionally or lyophilized starter *** quality characteristics of kefir produced at 22℃ and 30℃ using kefir grains after addition of microbial levan and pullulan were investigated for 14 ***,the survival of different gram-positive and gram-negative bacteria strains which were inoculated before and after fermentation were investigated during *** pH and titratable acidity were in the ranges of 4.67–4.39 and 1.10–0.87%,*** highest exopolysaccharide values(458.3–465.3 mg/kg)were found in the samples produced with the addition of 1%(w/v)of microbial levan at 30℃.Yeast counts were in the ranges of 6.73–5.11 log CFU/mL while the lactobacilli and lactic streptococci counts were in the ranges of 9.64–7.91 and 9.64–8.69 log CFU/mL,*** microbial polysaccharide addition did not show any significant differences in the enumeration of lactic acid bacteria in kefir(p>0.05).All gram-positive and gram-negative bacteria grew/survived during fermentation however Listeria monocytogenes was the most susceptible test bacterium to metabolites during *** highest reduction in the counts of *** was determined as 2.39 log units after 24 h of fermentation at 30℃ in the samples which were inoculated before fermentation and produced with the addition of *** samples produced at 30℃ without polysaccharide addition were considered as the best with respect to appearance,taste,consistency and overall acceptability.

关键词： Kefir grain Levan Pullulan Food-borne bacteria

Damage Mechanism of CK2 and IKAROS in Philadelphia Like Acute Lymphoblastic Leukemia

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Journal of Biosciences and Medicines 2024年第4期12卷 49-59页

作者： Ignacio vélez-Rodríguez victoria Carranza-Aranda Facultad Mexicana de Medicina Universidad La Salle Tlalpan M&#233xico Hospital general de Mé xico Cuauht&#233moc M&#233xico

Acute lymphoblastic leukemia (ALL) is characterized by immature and poorly differentiated B lymphocytes in large numbers in the blood. B cells are distinct from the cell types involved in their development (common lymphoid progenitor cells, pro-B cells, pre-B cells, and mature cells). The process of B cell maturation depends on precise communication within the cell: signals activate specific genes that are essential for proper development. Errors in this intricate signaling network can lead to issues with B cell function and contribute to disease. B-lineage acute lymphoid leukemias, malignancies of precursor-stage B lymphoid cells inhibit lymphoid differentiation, leading to abnormal cell proliferation and survival. The process of developing leukemia (leukemogenesis) can be triggered by an overproduction of both hematopoietic stem cells (the cells that form all blood cells) and the immature versions of white blood cells called lymphoblasts. Acute lymphoblastic leukemia (ALL) with the presence of the Philadelphia chromosome (ALL Ph) is classified as a high-risk manifestation of the disease, this chromosome is the product of the reciprocal translocation, whose product is a BCR-ABL fusion protein. It is a highly active tyrosine kinase that can transform hematopoietic cells into cytokine-independent. Hyperphosphorylation cascades inhibit the differentiating function of IKZF1 as a tumor suppressor gene which leads to an abnormal proliferation of B cells due to the presence of the Philadelphia chromosome;it inhibits the differentiating process, leukemogenesis involving immature B cells in the bloodstream can result from the uncontrolled growth and division of hematopoietic stem cells and immature lymphoblasts (the precursors to B cells).

关键词： Acute Lymphoblastic Leukemia IKAROS Dephosphorylation Philadelphia Chromosome CK2

The TELOMERE REPEAT BINDINg proteins TRB4 and TRB5 function as transcriptional activators of PRC2-controlled genes to regulate plant development

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Plant Communications 2024年第7期5卷 178-199页

作者： Simon Amiard Léa Feit Emmanuel vanrobays lauriane Simon Samuel Le goff Loriane Loizeau Léa Wolff Falk Butter Clara Bourbousse Fredy Barneche Christophe Tatout Aline v.Probst igReD CNRSInsermUniversite´Clermont Auvergne63000 Clermont-FerrandFrance Institut de biologie de I’Ecole normale supe´rieure(IBENS) Ecole normale supe´rieureCNRSINSERMUniversite´PSLParisFrance Institute of Molecular Biology 55128 MainzGermany

Plant-specific transcriptional regulators called TELOMERE REPEAT BINDINg proteins(TRBs)combine two DNA-binding domains,the gH1 domain,which binds to linker DNA and is shared with H1 histones,and the Myb/SANT domain,which specifically recognizes the telobox DNA-binding site ***1,TRB2,and TRB3 proteins recruit Polycomb group complex 2(PRC2)to deposit H3K27me3 and JMJ14 to remove H3K4me3 at gene promoters containing telobox motifs to repress ***,we demonstrate that TRB4 and TRB5,two related paralogs belonging to a separate TRB clade conserved in spermatophytes,regulate the transcription of several hundred genes involved in developmental responses to environmental ***4 binds to several thousand sites in the genome,mainly at transcription start sites and promoter regions of transcriptionally active and H3K4me3-marked genes,but,unlike TRB1,it is not enriched at H3K27me3-marked gene ***,TRB4 can physically interact with the catalytic components of PRC2,SWINgER,and CURLY LEAF(CLF).Unexpectedly,we show that TRB4 and TRB5 are required for distinctive phenotypic traits observed in clf mutant plants and thus function as transcriptional activators of several hundred CLF-controlled genes,including key flowering *** further demonstrate that TRB4 shares multiple target genes with TRB1 and physically and genetically interacts with members of both TRB ***,these results reveal that TRB proteins engage in both positive and negative interactions with other members of the family to regulate plant development through both PRC2-dependent and-independent mechanisms.

关键词： chromatin TRB proteins transcriptional regulation PRC2 plant development

Proterozoic to Phanerozoic case studies of laser ablation microanalysis for microbial carbonate U–Pb geochronology

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geoscience Frontiers 2024年第2期15卷 30-40页

作者： Yuxiang Jiang Simon v.Hohl Xiangtong Huang Shouye Yang state Key laboratory of Marine geology School of Ocean and Earth SciencesTongji UniversityShanghai 200092China

Some of the earliest bio-sedimentary records of life on Earth are represented by microbial carbonates,which are also critical geochemical archives of ancient seawater chemistry and the environmental circumstances in which they *** paleo-microbial environments on Earth and potentially other planets requires precise determination of the depositional ages of these ***(abiogenic)carbonate geochemistry communities can now use developments in in-situ laser ablation U-Pb dating using inductively coupled plasma mass spectrometry(la-ICP-MS).Due to the effects of impurity mixing and diagenesis,microbial carbonates have received little geochronological study despite their broad relevance for understanding ancient seawater’s environmental conditions and geochemical *** study demonstrates using time-of-flight mass spectrometry(TOF-MS)to perform quick,quantitative elemental mapping before U-Pb spot dating to improve experiment success rates and data reliability and offers four practical application examples.

关键词： Stromatolite Microbial carbonate Carbonate geochronology In-situ la-ICP-MS ICP-Time Of Flight-MS Trace element mapping

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妊娠期糖尿病产妇初乳的菌群分析

重庆医科大学学报 2024年第4期49卷 486-492页

作者：苟拉王安迪张华重庆医科大学附属第一医院妇产科重庆400016

目的:前瞻性研究妊娠期糖尿病(gestational diabetes mellitus,gDM)与正常产妇初乳菌群的丰度以及对其多样性进行评估分析。方法:选取符合纳入标准的30例gDM产妇作为实验组,30例健康产妇作为对照组,分娩方式均为剖宫产。从所有受试者乳... 详细信息

目的:前瞻性研究妊娠期糖尿病(gestational diabetes mellitus,gDM)与正常产妇初乳菌群的丰度以及对其多样性进行评估分析。方法:选取符合纳入标准的30例gDM产妇作为实验组,30例健康产妇作为对照组,分娩方式均为剖宫产。从所有受试者乳汁标本中分离获得DNA,在Illumina MiSeq平台进行16s rRNA基因v3~v4区扩增子高通量测序。结果:正常组与gDM组之间评估菌群的丰度指数的Ace指数有统计学差异(P=0.039)。2组研究对象的菌群在除Ace指数外的Alpha多样性上无差异,但在Beta多样性,差异有统计学意义(P=0.001)。gDM产妇母乳中厚壁菌门和变形菌门、链球菌科和孪生球菌科、链球菌属和罗斯氏菌属的相对丰度平均值均低于对照组,而放线菌门、葡萄球菌科、葡萄球菌属的相对丰度平均值较对照组水平更高。结论:gDM产妇与健康产妇初乳菌群的丰度以及多样性均有差异,gDM母乳中厚壁菌门以及变形菌门相对丰度的减少,可能对其子代早期肠道菌群的建立及早期的生长发育产生影响。定量母乳菌群的构成对该人群及其子代有特殊意义。

关键词：妊娠期糖尿病母乳微生物 16S核糖体RNA

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A study on wildfire impacts on greenhouse gas emissions and regional air quality in South of Orléans,France

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Journal of Environmental Sciences 2024年第1期135卷 521-533页

作者： Chaoyang Xue gisèle Krysztofiak Yangang Ren Min Cai Patrick Mercier Frédéric Le Fur Corinne Robin Benoit grosselin véronique Daele Max RMcgillen Yujing Mu valéry Catoire Abdelwahid Mellouki laboratoire de Physique et Chimie de l’Environnement et de l’Espace(LPC2E) CNRS–UniversitéOrléans–CNES(UMR 7328)Orléans Cedex 245071France Institut de Combustion AérothermiqueRéactivitéEnvironnement(ICARE)CNRSOrléans Cedex 245071France Research Centre for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Lig’Air-Association de surveillance de la qualitéde l’air en région Centre-val de Loire Saint-Cyr-en-Val 45590France Mohammed v University RabatMorocco

Wildfire events are increasing globally which may be partly associated with climate change,resulting in significant adverse impacts on local,regional air quality and global *** September 2020,a small wildfire(burned area:36.3 ha)event occurred in Souesmes(Loiret-Cher,Sologne,France),and its plume spread out over 200 km on the following day as observed by the MODIS *** on measurements at a suburban site(~50 km northwest of the fire location)in Orléans and backward trajectory analysis,young wildfire plumes were *** increases in gaseous pollutants(CO,CH_(4),N_(2)O,vOCs,etc.)and particles(including black carbon)were found within the wildfire plumes,leading to a reduced air *** factors,defined as EF(X)=ΔX/ΔCO(where,X represents the target species),of various trace gases and black carbon within the young wildfire plumes were determined accordingly and compared with previous *** in the ambient ions(such as ammonium,sulfate,nitrate,chloride,and nitrite in the particle-and gasphase)and aerosol properties(e.g.,aerosol water content,aerosol p H)were also quantified and ***,we estimated the total carbon and climate-related species(e.g.,CO_(2),CH_(4),N_(2)O,and BC)emissions and compared them with fire emission *** biomass burning emission inventories have uncertainties in estimating small fire burned areas and *** instance,we found that the global Fire Assimilation System(gFAS)may underestimate emissions(e.g.,CO)of this small wildfire while other inventories(gFED and FINN)showed significant *** that it is the first time to record wildfire plumes in this region,related atmospheric implications are presented and discussed.

关键词： Wildfire Air quality Emission factor Emission inventory vOLTAIRE supersite

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