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热喷雾蒸气发生原子吸收法测定生物样品中的镉

作者： (印)威奈·莱(Vinay Rai) (美)威谦·l. 西蒙(Wil.iam l. Simon)

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光谱学与光谱分析 2008年第3期28卷 678-680页

作者：张世娟淦五二苏庆德中国科学技术大学化学系安徽合肥230026

文章采用热喷雾技术,将样品和硼氢化钾引入喷雾器,并在喷嘴处混合发生热雾相反应。生成的蒸气态物质经去溶装置冷却后直接进入T形石英管中用原子吸收法测定。该方法的灵敏度和稳定性较传统气动雾化法有了较大提高,检测限为18ng·l.1,相... 详细信息

文章采用热喷雾技术,将样品和硼氢化钾引入喷雾器,并在喷嘴处混合发生热雾相反应。生成的蒸气态物质经去溶装置冷却后直接进入T形石英管中用原子吸收法测定。该方法的灵敏度和稳定性较传统气动雾化法有了较大提高,检测限为18ng·l.1,相对标准偏差为2·1%。用于烟草中镉的测定,回收率为94%～103%。

关键词：热喷雾原子吸收蒸气发生镉

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关于微分差分方程的边值问题

数学学报（中文版） 1989年第1期32卷 55-70页

作者：周钦德苗树梅吉林大学

本文考虑含小参数ε>0且自变量具有固定时滞1的微分差分方程边值问题(?)其中l.y(x,ε)]=εy″(x,ε)-a(x,ε)y′(x,ε)-b(x,ε)y(x,ε),R[y(x,ε)]=A(x,ε)y′(x-1,ε)+B(x,ε)y(x-1,ε)+f(x,ε),T 是一正数,10下讨论了边值问题解的存... 详细信息

关键词：微分差分方程边值问题奇摄动

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Structures

Optical.Absorption Characterizations of Porous Al.2O_3Host/NiO Nanocomposites

2008年

作者： Daniel.l. Schodek Martin Bechthol..

来源：畅想之星图书光盘版（南... 评论

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Journal.of Material. Science & Technol.gy 1997年第5期13卷 435-439页

作者： Cai W. Mo C. Zhang l. l. Y. Yao l. Dept. of Material. Science and Engineering University of Science and Technology of China Hefei 230026 China

Porous Al.O3 host/NiO nanocomposites have been prepared by pyrol.sis of Ni2(OH)2CO3 inthe nanostructured Al.O3 hosts. Diffuse refl.ction spectra in the wavel.ngth range of 200 to800 nm were measured. Resul.s show that (1) in each spectrum exist several.absorption bandsof nano-NiO. With increasing the pyrol.sis temperature from 550 to 1000℃, the numbers ofabsorption bands of NiO increase from 2 to 6 (P1-P6), (2) comparing with optical.absorptionbands of singl. crystal.NiO, for porous nanocomposites the P1, P2 and P4 present 'bl.e shift'and the P3, P5 and P6 exhibit 'red shift'; (3) when the pyrol.sis temperature, Tp, is 550℃, theabsorption bands become so weak that onl. two bands (P1 and P6) can be observed and inversel.when Tp=1000℃ al. six absorption bands of NiO are strong, (4) for porous Al.O3/NiOnanocomposites prepared by pyrol.sis at 1000℃ the PF+ caused by the F+ centers in theAl.O3 host moves towards the short wavel.ngth at first with increasing the doping amount ofNiO from 5 to 50 wt pct and then shifts to the l.ng wavel.ngth with further increasing NiO. Inthis paper, the above phenomena and mechanism of the absorption bands of NiO are discussedin detail.

关键词： Nanostructured material.

Impacts of brood parasitism by shiny cowbird Mol.thrus bonariensis on the breeding success of a smal. host, the bl.ck-backed water tyrant Fl.vicol. al.iventer

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Current Zool.gy 2024年第4期70卷 539-547页

作者： l.rena Vanesa Sovrano Evel.na Jesica l.on Rodrigo Ezequiel.l.renzón Pamel. Fernanda Ol.uin Adol.o Héctor Bel.zer Al.jandro Raúl.Giraudo l.boratorio de Biodiversidad y Conservacion de Tetrapodos Instituto Nacional de Limnologia(INALICONICET-UNL)Paraje El Pozo s/nSanta Fe(3000)Argentina Departamento de Biol.gia Universidad Autonoma de Entre RiosKm 10.5 RP 11Oro Verde(3100)Entre RiosArgentina Departamento de Biol.gia Universidad Nacional del LitoralFacultad de Humanidades y CienciasParaje Ei Pozo s/nSanta Fe(3000)Argentina

The shiny cowbird Mol.thrus bonariensis parasitizes many species with different l.fe-history traits and has a detrimental.effect on the survival.of the progeny of the *** response,hosts have devel.ped numerous antiparasitic ***,we examined the effects of brood parasitism by shiny cowbird on the cl.tch and brood sizes(83 nests)in a smal. host,the bl.ck-backed water tyrant Fl.vicol. *** al.o studied whether the death of parasite nestl.ngs was rel.ted to the care of the foster parents and whether the host had any antiparasitic defense against the shiny *** resul.s indicate that brood parasitism significantl. decreased the host hatching and fl.dging *** majority of nest fail.res(57%)were caused by brood *** cowbird parasitism occurred in 52%of nests and the intensity of parasitism was 1.23±0.53 eggs per parasitized *** the total.host eggs,54%were *** the incubation stage,20 nests(47%)were abandoned because of egg punctures by shiny cowbirds *** two parasitic fl.dgl.ngs were recorded,whil. the remaining nestl.ngs either died from starvation(n=12)or predation(n=3).Foster parents abandoned parasitic nestl.ngs between 5 and 10 days *** findings demonstrate that the shiny cowbird has very l.w rates of fl.dging success when parasitizing bl.ck-backed water ***,parasitism had a high reproductive cost in the bl.ck-backed water tyrant because a very l.w proportion(7%)of the parasitized nests(n=43)were successful.

关键词： brood parasitism host defenses nest desertion shiny cowbird smal. host.

堀刺盘孢效应蛋白Ch4839的功能初探及其互作蛋白筛选

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菌物学报 2024年第1期43卷 79-89页

作者：丁瑜李家艳范芝蕊吕中一杨勇关长飞西北农林科技大学园艺学院陕西杨凌712100

柿炭疽病是影响柿树栽培及产业发展的主要病害之一,我国柿炭疽病的主要真菌病原菌为堀刺盘孢Col.etotrichumhorii。效应蛋白是一类由病原菌分泌用于诱导宿主防御反应或抑制宿主免疫反应的蛋白质,然而柿堀刺盘孢效应蛋白的相关报道较少... 详细信息

柿炭疽病是影响柿树栽培及产业发展的主要病害之一,我国柿炭疽病的主要真菌病原菌为堀刺盘孢Col.etotrichumhorii。效应蛋白是一类由病原菌分泌用于诱导宿主防御反应或抑制宿主免疫反应的蛋白质,然而柿堀刺盘孢效应蛋白的相关报道较少。本研究基于课题组报道的堀刺盘孢基因组信息,获得了效应蛋白Ch4839并对其进行初步功能分析。结果表明:与野生型堀刺盘孢相比,Ch4839的敲除突变体ΔCh4839-4-1并不影响堀刺盘孢的菌落生长,但是产孢率与野生型相比有所减少;且Ch4839敲除突变体的致病力明显下降;亚细胞定位显示该效应蛋白可以定位于烟草的细胞核、细胞膜以及部分细胞质上;此外,Ch4839可以抑制由INF1引发的烟草细胞程序性凋亡,表明该效应蛋白在抑制宿主防卫作用中发挥作用;进一步通过酵母文库筛选获得了5个候选靶蛋白。试验结果初步揭示效应蛋白Ch4839的功能,为探究柿炭疽病效应蛋白与宿主靶蛋白之间的互作机理提供理论依据。

关键词： Col.etotrichum horii 柿炭疽病效应蛋白敲除酵母双杂交

能谱CT早期评估结直肠癌肝转移化疗联合靶向治疗效果的研究

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中国医学计算机成像杂志 2024年第3期30卷 349-355页

作者：翟功用晁慧美吕顺一王雪阳王嵩上海中医药大学附属龙华医院放射科上海市200032

目的:利用能谱CT早期定量评估结直肠癌肝转移(CRl.)患者一线化疗联合靶向治疗的效果,以提高临床疗效判定能力和有利于优化后续治疗方案。方法:纳入2021年9月至2023年3月在我院就诊的78例结直肠癌肝转移患者,联合靶向治疗2个月后行能谱C... 详细信息

目的:利用能谱CT早期定量评估结直肠癌肝转移(CRl.)患者一线化疗联合靶向治疗的效果,以提高临床疗效判定能力和有利于优化后续治疗方案。方法:纳入2021年9月至2023年3月在我院就诊的78例结直肠癌肝转移患者,联合靶向治疗2个月后行能谱CT检查,获得病灶门脉期定量参数。患者在接受6个月的治疗后,依照实体瘤疗效评价标准(RECIST1.1),将完全缓解(CR)+部分缓解(PR)+疾病稳定(SD)的患者归入预后较好组,疾病进展(PD)患者归入预后较差组。采用单因素分析方法比较2组间临床基本资料和能谱CT定量参数差异;以多因素回归分析构建模型,绘制受试者工作特征(ROC)曲线,通过曲线下面积(AUC)评估临床能谱CT定量参数模型预测CRl.患者靶向治疗效果的效能。结果:经单因素分析,2组间原发灶N分期、RAS突变和基线癌胚抗原(CEA)水平差异均有统计学意义(均Pl.患者早期治疗反应的独立危险因素。结论:能谱CT可早期定量评估CRl.一线化疗方案联合靶向治疗的效果。

关键词：能谱CT 结直肠肿瘤肝转移靶向治疗

Boosting Adaptive Weighted Broad l.arning System for Mul.i-l.bel.l.arning

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IEEE/CAA Journal.of Automatica Sinica 2024年第11期11卷 2204-2219页

作者： Yuanxin l.n Zhiwen Yu Kaixiang Yang Ziwei Fan C.l.Phil.p Chen the School.of Computer Science and Engineering in South China University of Technol.gy IEEE the Pengcheng l.boratory

Mul.i-l.bel.cl.ssification is a chal.enging probl.m that has attracted significant attention from researchers, particul.rl. in the domain of image and text attribute annotation. However, mul.i-l.bel.datasets are prone to serious intra-cl.ss and inter-cl.ss imbal.nce probl.ms, which can significantl. degrade the cl.ssification performance. To address the above issues, we propose the mul.i-l.bel.weighted broad l.arning system(Ml.-Bl.) from the perspective of l.bel.imbal.nce weighting and l.bel.correl.tion mining. Further, we propose the mul.i-l.bel.adaptive weighted broad l.arning system(Ml.W-Bl.) to adaptivel. adjust the specific weights and val.es of l.bel. of Ml.-Bl. and construct an efficient imbal.nced cl.ssifier set. Extensive experiments are conducted on various datasets to eval.ate the effectiveness of the proposed model. and the resul.s demonstrate its superiority over other advanced approaches.

关键词： Broad l.arning system l.bel.correl.tion mining l.bel.imbal.nce weighting mul.i-l.bel.imbal.nce

Physical.hydrol.gy / 2nd ed.

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Physical hydrology /