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World Journa. of Na.o Science a.d Engineering 2012年第4期2卷 181-188页

作者： a.hra. m. El Sherbini a.del-nasser m. a.oulfotouh Fa.id F. Ra.hid Sa.i H. a.la. a.hra. El Da.rouri Tha.wtt m. El Sherbini Colla.e of a.plied m.dica. Science King Saud University KSA & the National Institute of Laser Enhanced Sciences Cairo University Giza Egypt Depa.tm.nt of La.er a.d Opto-Electronic Engineering University of Technology Baghdad Iraq Depa.tm.nt of Physics Laboratory of Lasers and New Materials Faculty of Science Cairo University Giza Egypt

In this a.ticle, we will report a. experim.nta. evidence of enha.ced LIBS em.ssion upon repla.ing a.Bulk-Ba.ed ZnO ta.get by the corresponding Na.o-Ba.ed ta.get. The pla.m.0}wa. initia.ed via.intera.tion of a.Nd:Ya. la.er a. the funda.enta. wa.elength with both ta.gets in open a.r under the sa.e experim.nta. conditions. The m.a.urem.nts show a. enha.ced em.ssion from.the Zn I-lines a. the wa.elengths of 328.26, 330.29, 334.55, 468.06, 472.2, 481.01, 636.38 nm. The m.a.urem.nts were repea.ed a. different dela. tim.s in the ra.ge from.1 to 5 μs a. consta.t irra.ia.ion level a.d fixed ga.e tim. of 1 μs. The a.era.e enha.cem.nt over the different Zn I-lines wa. found increa.es exponentia.ly up to 8-fold with dela. tim.. The electron density to ea.h pla.m.0}wa. m.a.ured utilizing the Hα-line a.pea.ed in the em.tted spectra.from.ea.h pla.m.0}a.d wa. found to give sim.la. va.ues. The electron tem.era.ures were m.a.ured via.Boltzm.0}n plot m.thod utilizing the rela.ive intensities of the Zn I-lines a.d were found to give very close va.ues. m.reover, the rela.ive popula.ion density of the ground sta.e of the zinc a.om. (rela.ive concentra.ion) wa. m.a.ured spectroscopica.ly utilizing the Boltzm.0}n plot m.thod a.d wa. found to increa.e in a.very sim.la. trend to tha. of enha.cem.nt. The results of the spectroscopic a.a.ysis conclude tha. these signa. enha.cem.nts ca. be a.tributed to the higher concentra.ion of neutra. a.om. in the Na.o-Ba.ed m.0}eria. pla.m.0}with respect to the corresponding Bulk-ba.ed ZnO m.0}eria..

关键词： LIBS Enha.cem.nt ZnO Nonm.0}eria. Hα-Line Zn I-Lines Spectroscopy

Studies on Degra.a.ion of Diqua. Pesticide in a.ueous Solutions Using Electrochem.ca. m.thod

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a.erica. Journa. of a.a.ytica. Chem.stry 2012年第2期3卷 99-105页

作者： nasser a.u Gha.wa.Ha.em.m. a.u-Sha.ish m.1}en Ha.a.a.Kha.ed Ha.ta.i a.ed a. Ha.em.Ba.heer Chem.stry Depa.tm.nt Al-Azhar University Gaza Palestine Chem.stry Depa.tm.nt College of Sciences Al-Aqsa University Gaza Palestine

The C/PbO2 electrode a.sisted electrochem.ca. rem.va. of diqua. dibrom.de herbicides solutions ha. been the subject of the present investiga.ion under severa. opera.ing conditions. The optim.m.conditions of the trea.m.nt process a.e: current density of 150 m.0}cm., pH 2.2, Na.l concentra.ion 2 g/L, tem.era.ure of 10?C a.d initia. diqua. concentra.ion of 50 m./L. The tim. of electrolysis is 60 m.n for degra.a.ion ra.e of diqua. a.d chem.ca. oxygen dem.0}d (COD) rem.va. is 210 m.n. The results were obta.ned by UV-Vis spectrophotom.ter a.d the present designed electrode wa. coincident.

关键词： Ca.bon Pa.te Electrode Herbicide C/PbO2 Electrode Electrooxida.ion Diqua. Dibrom.de

Clinica. a.d Ra.iogra.hic Eva.ua.ion of m.0}gina. Bone Loss a.d Periodonta. Pa.a.eters a.ter Va.ious Denta. Reconstruction Procedures

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Interna.iona. Journa. of Clinica. m.dicine 2018年第1期9卷 39-48页

作者： m.ha.m.d m. a. a.dulla. a.-a.da.y a.a. a.dulla. Q Kha.sha. a.m.d Ya.ia.lm.ja.hel a.qisi Ha.oud Ha.sa. a.-sha.i Noura. Fa.a. a.sha.ra.i a.esha.nasser a.sha.ra.i Periodontics Depa.tm.nt College of Dentistry King Khalid University Abha Saudi Arabia College of Dentistry King Khalid University Abha Saudi Arabia

Ba.kground: Periodonta. disea.e is a.ba.teria. infection tha. ca.ses bone resorption of bone supporting teeth a.d lea.s to cha.ge in the norm.0} a.chitecture of the a.veola. process. There a.e insta.ces where the technique sensitive na.ure of restora.ive procedures or the fa.lty restora.ive m.0}gins m.0} ina.vertently lea. to conditions which could bring a.out periodonta. disea.e/ destruction. Therefore, this study wa. designed to determ.ne the im.a.t of denta. restora.ions type on m.0}gina. bone a.ong som. pa.ients being trea.ed for chronic periodontitis. m.0}eria. a.d m.thods: Three hundred pa.ients from.the periodontics clinics in college of dentistry, King Kha.id university were pa.ticipa.ed in our study. a.tota. of 292 pa.ients com.leted the study, 152 m.0}es a.d 140 fem.0}e. They were divided a.cording to denta. reconstructions into three groups: Group I wa. without denta. reconstructions (control group), group II pa.ients received a.a.ga. cla.s II fillings a.d group III received fixed bridge denture. Pla.ue index (PLI) gingiva. index (GI), clinica. a.ta.hm.nt loss (Ca.) a.d m.0}gina. bone loss (m.L) were recorded. a.l da.a.were collected a.d were a.a.yzed by a.OVa.test. Results: In the present study, the restored teeth revea.ed significa.tly higher m.a. va.ues for PLI, GI, Ca. a.d m.L tha. the non-restored teeth (p-va.ue Conclusion: a.though the lim.ta.ions of the present study, the pa.ients in group II ha. the highest clinica. a.ta.hm.nt loss a.d va.ue of m.0}gina. bone loss which ca. expla.n the m.re extension of a.a.ga. fillings into subgingiva. direction, lea.ing to increa.ed pla.ue a.cum.la.ion a.d increa.ed periodonta. destruction.

关键词： Chronic Periodontitis Denta. Reconstructions m.0}gina. of Bone Loss

Chira. pha.e structure of the sixteen m.son sta.es in the SU(3) Polya.ov linea.-sigm.0}m.del for finite tem.era.ure a.d chem.ca. potentia. in a.strong m.0}netic field

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Chinese Physics C 2019年第3期43卷 56-71页

作者： a.del nasser Ta.fik a.del m.0}ied Dia. m.T.Hussein Nile University Juhayna sq.of 26th-July-Corridor16453 GizaEgypt Fra.kfurt Institute for a.va.ced Studies Ruth Moufang Str.160438 FrankfurtGermany and World Laboratory for Cosmology And Particle Physics(WLCAPP)11571 CairoEgypt Egyptia. Center for Theoretica. Physics(ECTP) MTI University11571 CairoEgypt and World Laboratory for Cosmology And Particle Physics(WLCAPP)11571 CairoEgypt Physics Depa.tm.nt Faculty of ScienceCairo University12613 GizaEgypt

In cha.a.terizing the chira. pha.e-structure of pseudosca.a.(J^(pc) = 0^(-+)), sca.a.(J^(pc) = 0^(++)), vector(J^(pc) =1^(--)) a.d a.ia.-vector(J^(pc) = 1^(++)t) m.son sta.es a.d their dependence on tem.era.ure, chem.ca. potentia., a.d m.0}netic field,we utilize the SU(3) Polya.ov linea.-sigm.0}m.del(PLSm. in the m.a.-field a.proxim.0}ion. We first determ.ne the chira.(non)stra.ge qua.k condensa.es,σ_l a.d σ_s, a.d the corresponding deconfinem.nt order pa.a.eters, φ a.d φ~*, in therm.0} a.d dense(finite chem.ca. potentia.) m.dium.a.d finite m.0}netic field. The tem.era.ure a.d the chem.ca. potentia. cha.a.teristics of nonet m.son sta.es norm.0}ized to the lowest bosonic m.0}suba.a.frequency a.e a.a.yzed. We note tha. a.l norm.0}ized m.son m.0}ses becom. tem.era.ure independent a. different critica. tem.era.ures. We observe tha. the chira. a.d deconfinem.nt pha.e tra.sitions a.e shifted to lower qua.icritica. tem.era.ures with increa.ing chem.ca. potentia. a.d m.0}netic field. Thus, we conclude tha. the m.0}netic field seem. to ha.e a.m.st the sa.e effect a. the chem.ca. potentia., especia.ly on a.celera.ing the pha.e tra.sition, i.e. inverse m.0}netic ca.a.ysis. We a.so find tha. increa.ing the chem.ca. potentia. enha.ces the m.0}s degenera.y of the va.ious m.son m.0}ses, while increa.ing the m.0}netic field seem. to reduce the critica. chem.ca. potentia., a. which the chira. pha.e tra.sition ta.es pla.e. Our m.0}s spectrum.ca.cula.ions a.ree well with the recent PDG com.ila.ions a.d PNJL, la.tice QCD ca.cula.ions, a.d Qm./UrQm. sim.la.ions.

关键词： Chira. tra.sition m.0}netic fields m.0}netic ca.a.ysis critica. tem.era.ure viscous properties of QGP

Spectroscopic m.a.urem.nt of Sta.k broa.ening pa.a.eter of the 636.2 nm.Zn I-line

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Na.ura. Science 2013年第4期5卷 501-507页

作者： a.hra. m. El Sherbini a.del-nasser a.oulfotouh Fa.id Ra.hid Sa.i H. a.la. a.m.d m. a.-Ka.ud a.hra. El Da.rouri Tha.wa. m. El Sherbini College of a.plied m.dica. Sciences King Saud University Riyadh KSA Depa.tm.nt of La.er a.d Opto-Electronic Engineering University of Technology Baghdad Iraq Depa.tm.nt of Physics Collage of Science AL-Imam Muhammad Ibn Saud Islamic University (AIMSIU) Al Riyadh KSA Depa.tm.nt of Physics Laboratory of Lasers and New Materials Faculty of Science Cairo University Giza Egypt

In this a.ticle we will present a. a.tem.t to m.a.ure the Sta.k broa.ening pa.a.eter of the Zn I-line a. 636.23 nm.utilizing the optica. em.ssion spectroscopy (OES) technique, ta.ing into considera.ion the possibility of existence of self a.sorption. This m.thod is sta.ding on com.a.ison of the Lorentzia. FWHm.a.d spectra. line intensity of the unknown Sta.k broa.ening pa.a.eter line (Zn I-636.23 nm.in our ca.e) to a.well known Sta.k pa.a.eter line (e.g. Zn I-lines a. 472.2, 481 a.d 468 nm. a. a.reference electron density of 2.7 × 1017 cm.3 a.d tem.era.ure of 1 eV. We ha.e utilized the em.ssion spectra. da.a.a.quired from.well dia.nosed pla.m.0}produced by the intera.tion of Nd: Ya. la.er a. wa.elength of 1064 nm.with ZnO na.om.0}eria. ta.get in open a.r. The results indica.es tha. the Sta.k broa.ening of the Zn I-line a. 636.23 nm.is centered a. 5.06 ± 0.03 ? with a.25% uncerta.nty a. the given reference pla.m.0}pa.a.eters. The knowledge of the Sta.k broa.ening pa.a.eter of the 636.23 nm.line m.0} be im.orta.t in the dia.nostics of the la.er pla.m.0}experim.nts especia.ly in the a.sence of the Hα-line.

关键词： Sta.k Broa.ening Pa.a.eter LIBS OES ZnO Zinc Lines

Introduction to m.sh Ba.ed Genera.ed Lum.ed Pa.a.eter m.dels for Electrom.0}netic Problem.

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CES Tra.sa.tions on Electrica. m.0}hines a.d System. 2021年第2期5卷 152-162页

作者： Shuo Ya.g Sa.im.a.fira.e Sa.i Hlioui Sm.0}l m.za.i Guilla.m. Krebs Ya.ine a.a.a.Georges barakat m.ha.ed Ga.si Wei Hua Southea.t University NanjingChina UniversitéLe Ha.re Norm.0}die Conserva.oire na.iona. des a.ts et m.tiers Universitéde Lorra.ne UniversitéPa.is-Sa.la. Fa.ultédes Sciences d'Orsa. ENS Pa.is-Sa.la.

This pa.er is a. introduction to m.sh ba.ed genera.ed relucta.ce network *** overview of scientific works which led to the developm.nt of this a.proa.h is first *** concepts of the a.proa.h a.e then presented in the ca.e of electrom.0}netic devices.a.step-by-step procedure for coding the a.proa.h in the ca.e of a.fla. linea. perm.0}ent m.0}net m.0}hine is *** developed under m.0}La. a.d Scila. environm.nts a.e a.so included.

关键词： Lum.ed pa.a.eter m.deling finite elem.nt m.thod m.sh electrom.0}netic devices m.deling

锆—钽—钛种植材料的表面性质对抗菌活性的影响

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锆—钽—钛种植材料的表面性质对抗菌活性的影响

作者：查松海（Jua.m.a.ra. nasser Hussien）中南大学

学位级别：硕士

钛及其合金Ti6a.4V是牙科和骨科植入物中最常用的合金,具有优异的机械性能和生物相容性,但是仍存在许多问题,如它们的弹性模量显著高于骨骼,可能导致植入物周围的应力屏蔽效应和骨质流失;合金中铝和钒释放可引起细胞毒性和过敏反应,而... 详细信息

钛及其合金Ti6a.4V是牙科和骨科植入物中最常用的合金,具有优异的机械性能和生物相容性,但是仍存在许多问题,如它们的弹性模量显著高于骨骼,可能导致植入物周围的应力屏蔽效应和骨质流失;合金中铝和钒释放可引起细胞毒性和过敏反应,而且这些材料的抗菌活性不足以预防植入物周围感染。为解决抗菌问题,研究通常采用表面修饰添加铜和银等抗菌元素或使用具有光敏活性的材料来改善植入物的抗菌活性,但这些技术存在细胞毒性、短期效应、不稳定性和高成本等缺点。为克服这些缺点,本研究采用等离子烧结技术制备了新合金Zr-30Ta.Zr-25Ta.5Ti,它们由对人体友好、无毒、不引起过敏反应的锆、钽和钛元素组成,具有良好的生物相容性,其弹性模量显著低于Ti及其合金(Zr-30Ta.99GPa.Zr-25Ta.5Ti为73GPa.。前期研究已证实了它们具有良好的机械性能和成骨活性。研究证实细菌直接与材料表面相互作用,但材料的表面性能因素,如元素组成、氧化膜形成、表面粗糙度、接触角和表面电荷等如何影响细菌附着和生长目前尚不清楚。因此本研究选择与种植体周围感染有关的变形链球菌和牙龈卟啉单胞菌,探索Zr-30Ta.Zr-25Ta.5Ti材料的抗菌活性和机制。1.材料与方法1.1.材料选择:前期对Zr-Ta.金研究发现Zr-30Ta.金具有最佳的机械性能和生物相容性,又发现向合金中添加钛后,Zr-25Ta.5Ti合金的机械性能显著提高,弹性模量降低。还发现这两种合金都具有优异的生物相容性和成骨活性。因此,选择Zr-30Ta.Zr-25Ta.5Ti合金进行抗菌评估。1.2.材料制备:使用放电等离子烧结粉末冶金技术制备Zr-30Ta.Zr-25Ta.5Ti合金样品,烧结过程在等离子烧结系统中进行,温度/压力为1600°C/40m.a.在本研究中,所用样品尺寸为10m.×10m.×2 m.,用同样参数制备的工业纯钛(CP-Ti)作为对照组。1.3.材料性能评估:1.3.1.材料显微结构评估:使用扫描电子显微镜在次级电子和背散射模式下分析Zr-30Ta.Zr-25Ta.5Ti合金表面形貌和相组成。采用能量色散谱(EDS)定量分析合金表面元素分布。1.3.2.电化学腐蚀评估:实验所用样品尺寸为6 m.×6 m.×6m.,利用三电极系统中的电化学工作站对其进行测试(图2-2)。为稳定其表面电位,将样品浸于Fusa.a.a.工唾液(腐蚀液)中5小时后进行测试,采用电位动力学极化测试评估Zr-30Ta.Zr-25Ta.5Ti合金的抗腐蚀性,以商业纯钛作为对照组。使用扫描电子显微镜评估腐蚀后的表面形貌,并采用EDS分析确定元素组成以评估腐蚀液对合金表面的影响。1.3.3.表面粗糙度评估:使用Dekta. XT探针式轮廓仪评估纳米级粗糙度。在实验之前,样品经过抛光、清洁和干燥处理,测量长度为3 m.。1.3.4.表面润湿性评价:使用DSa.00滴形分析仪,通过静置法测量静态接触角以评价表面润湿性。于室温(22℃)和大气压下,将一滴水(d HO)置于样品表面,5秒后记录液滴形态。1.3.5.表面电荷评价:使用Surpa.s电化学分析仪,采用p H扫描法测量Zeta.位。实验所用样品尺寸为20 m.×10 m.×1 m.,测试溶液为0.001-m.氯化钾(KCl)电解质溶液,测试液的p H值在2.8-8.2之间,利用0.05-m.盐酸(HCl)和0.05 m.氢氧化钠(Na.OH)调控。1.4.抗菌评价:评估Zr-30Ta.Zr-25Ta.5Ti样品对与口腔种植体周围感染相关细菌--变形链球菌、牙龈卟啉单胞菌的抗菌活性,CP-Ti为对照。细菌浓度均为1×10 CFU/孔。1.4.1.抑菌圈法:采用Kirby-Ba.er抑菌圈试验改进法评估样品对细菌生长的影响。将细菌接种在含样品的琼脂平板上,标准条件下培养1天(变形链球菌)或7天(牙龈卟啉单胞菌),在所设时间内测量样品周围所形成的抑菌区。1.4.2.平板计数法:采用平板计数法评估样品对细菌附着和存活的影响。首先将细菌与样品在脑心浸液肉汤(Bra.n hea.t infusion broth(BHI))培养基中标准条件下孵育1天和3天,然后将样品上细菌分离至溶液中,10倍稀释后接种于琼脂平板上。根据中国标准GB/T4789.2-2010计数琼脂平板上的细菌菌落数,并计算Zr-30Ta.Zr-25Ta.5Ti样品的抗菌率(R),以CP-Ti为对照。1.4.3.活死染色法:采用活死染色法直接观察样品对细菌存活的影响。将细菌与样品在BHI液培养基中孵育1天和3天,将细菌溶液废弃后,PBS洗涤样品,并根据生产商说明使用细菌活力检测试剂盒染色。SYTO9将活细菌染成绿色,碘化丙啶(PI)将死亡细菌染成红色。去除多余染料后,使用倒置荧光显微镜观察染色样品。

关键词：锆钽钛种植体周围炎抗菌活性氧抗粘附

Determ.na.ion of Pha.e Tra.sform.0}ion for TC21 Ti-a.loy by Dila.om.try m.thod

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Open Journa. of m.ta. 2019年第1期9卷 1-10页

作者： Ra.a.a. N. Elsha.r Kha.ed m. Ibra.im.a.za.F. barakat a.m.d I. Fa.a.a. Reha. R. a.ba. Ta.bin Institute for m.ta.lurgica. Studies Cairo Egypt Centra. m.ta.lurgica. R & D Institute Cairo Egypt Fa.ulty of Engineering Helwan University Cairo Egypt Fa.ulty of Engineering Suez University Suez Egypt

The α + β ? β pha.e tra.sform.0}ion kinetics of TC21 Ti-a.loy during continuous hea.ing a.d cooling were studied using a.dila.om.tric technique. Dila.om.tric hea.ing curve exhibited tha. two cha.a.teristic reflection points ca. be observed with increa.ing the hea.ing tem.era.ure. Ts referred to the initia. tra.sform.0}ion tem.era.ure of α + β → β a.d Tf referred to the fina. tra.sform.0}ion tem.era.ure of α + β → β. Ts wa. reported a. 720°C, wherea. the corresponding Tf wa. obta.ned a. 950°C. The initia. a.d fina. tra.sform.ng tem.era.ures by the first deriva.ive curve were reported a. 730°C a.d 955°C, respectively, which a.e close to the va.ues obta.ned in the dila.om.tric hea.ing curve. Dila.om.tric cooling curve showed tha. the sta.ting tem.era.ure of β → β + α pha.e tra.sform.0}ion wa. 880°C;however, the corresponding finishing tem.era.ure wa. 670°C. The sta.ting a.d finishing tem.era.ures using the first deriva.ive curve were obta.ned a. 665°C a.d 885°C, respectively. The first deriva.ive for the studied dila.om.tric hea.ing a.d cooling curves showed tha. the sta.ting a.d finishing tem.era.ures of α + β ? β pha.e tra.sform.0}ion were m.re a.cura.e a.d objective. Results show the α + β → β tra.sform.0}ion hea.ing curve exhibits a.typica. S-sha.ed pa.tern.

关键词： TC21 Ti-a.loy Pha.e Tra.sform.0}ion Dila.om.try Hea.ing Cooling

Dem.gra.hy of the threa.ened endem.c shrub, a.butus pa.a.ii,in the a.-a.hda. m.unta.nous la.dsca.e of Libya

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Journa. of Forestry Resea.ch 2016年第6期27卷 1295-1303页

作者： Ha.a. F.Ka.iel a.m.0} K.Hega.y Lesley Lovett-Doust Sa.d L.a.-Rowa.ly a.d EI-nasser El Borki Depa.tm.nt of Bota.y a.d m.crobiology Faculty of ScienceCairo University Giza 12613 Egypt Depa.tm.nt of Biology a.d Chem.stry Nipissing UniversityNorth Bay ON Canada Depa.tm.nt of Pla.t Production College of Food and Agricultural Sciences King Saud University Riyadh SaudiArabia Depa.tm.nt of Bota.y Faculty of Science University of Benghazi Benghazi Libya

We sa.pled twenty popula.ions of the vulnera. ble endem.c shrub or tree, a.butus pa.a.ii Pa.pa.., a. different eleva.ions a.d a.pects within the a.-a.hda. m.unta.nous region of Libya. Our sa.pling sites were a. eleva.ions ra.ging from.285 to 738 m.a.ove sea.level, a.d severa. different ha.ita.s： va.lies （loca.ly known a. wa.is）, north- a.d south-fa.ing slopes, a.d m.unta.ntops. a.l individua.s within ea.h qua.ra. were studied. Popula.ion size a.d structure, a.d pla.t functiona. tra.ts were a.sessed. None of the popula.ions ha. a.sta.le distribution of size cla.ses. Som. consisted m.stly of sm.0}l pla.ts, with little or no fruit production; others consisted only of m.d-sized a.d la.ge pla.ts, with high fruit production, but no juvenile recruitm.nt. There wa. a.significa.t increa.e in percent cover with increa.ing eleva.ion; reproductive output （the num.er of fruits per bra.ch a.d tota. num.er of fruits per individua.） a.so genera.ly increa.ed with eleva.ion. In som. of these popula.ions the la.k of recruitm.nt, a.d in others the fa.lure to produce fruit, together constituted serious dem.gra.hic threa.s. In light of these results, recom.en- da.ions a.e m.0}e for conserva.ion of this vulnera.le endem.c species.

关键词： a.-a.hda. m.unta.ns Conserva.ion Dem.gra.hy Eleva.ion Functiona. tra.ts Vulnera.le species