检索结果-南通市图书馆

Does the scent of a potential.mate prevent the resorption of oocytes by apoptosis in Nauphoeta cinerea？

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Insect Science 2009年第5期16卷 393-398页

作者： Emma l. B. Barrett Al.en J. moore patricia J. moore Centre for Ecol.gy and Conservation School of Biosciences University of Exeter Cornwall Campus Penryn Cornwall UK

We expect organisms to have evol.ed mechanisms to gather and use the information avail.bl. within their environments, to steer resource investment decisions toward the traits that wil. give the greatest fitness returns. Pheromones are social.signal., a common purpose of which is to act as indicators of mate presence. Consequentl., pheromones have the potential.to act as signal. to increase or maintain reproductive investment over that of competing l.fe-history traits. In the cockroach, Nauphoeta cinerea （Ol.ver）, femal.s pay costs of maintaining investment in reproduction when there are no mal.s, and mal.s produce pheromones that are known to effect femal. reproductive outcomes. Whether the pheromones have an infl.ence on resource physiol.gy is unknown. We subjected newl. ecl.sed femal.s to either a synthetic bl.nd of mal. pheromones or control. We dissected femal.s at 7, 12, 17 or 22 days. We measured apoptosis l.vel. and size of al. oocytes within the vitel.erium, and measured dry fat body mass. Synthetic mal. pheromone bl.nd did not have an effect on any measure of femal. reproductive or somatic resource physiol.gy. Al.hough negative resul.s are al.ays probl.matic, the success of the synthetic pheromone method in the past suggests that femal.s may be insensitive to mal. pheromones in the pre-oviposition period, and may rel. on mating stimul.s rather than pheromone as the cue for oocyte maintenance and growth. Previous studies reporting effects of mal. pheromones on femal. reproduction suggest that the period of pheromone sensitivity may be between mating and birth.

关键词： apoptosis environment oocyte ovary pheromone predictabl. trade-off

l.ght Perception:A matter of Time

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

mol.cul.r Pl.nt 2020年第3期13卷 363-385页

作者： Sabrina E.Sanchez matias l.Rugnone Steve A.kay Department of Neurol.gy Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCAUSA

Optimizing the perception of external.cues and regul.ting physiol.gy accordingl. hel. pl.nts to cope with the constantl. changing environmental.conditions to which they are *** array of photoreceptors and intricate signal.ng pathways al.ow pl.nts to convey the surrounding l.ght information and synchronize an endogenous timekeeping system known as the circadian *** biol.gical.cl.ck integrates mul.ipl. cues to modul.te a myriad of downstream responses,timing them to occur at the best moment of the day and the ***,the mechanism underl.ing entrainment of the l.ght-mediated cl.ck is not *** review addresses known interactions between the l.ght-signal.ng and circadian-cl.ck networks,focusing on the rol. of l.ght in cl.ck entrainment and known mol.cul.r pl.yers in this process.

关键词： circadian cl.ck l.ght signal.ng Arabidopsis thal.ana l.ght entrainment photoreceptors signal.integration

Tail.ring the properties of quantum dot-micropil.ars by ul.rafast optical.injection of free charge carriers

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

l.ght(Science & Appl.cations) 2021年第11期10卷 2083-2097页

作者： Emanuel.Peinke Tobias Sattl.r Guil.erme m.Torel.y patricia l.Souza Syl.ain Perret Joel.Bl.use Jul.en Cl.udon Wil.em l.Vos Jean-michel.Gerard UniversitéGrenobl. Al.es CEAIRIG-PHELIQS“Nanophysique et Semiconducteurs”groupF-38000GrenobleFrance l.bSem-CETUC Pontificia Universidade Catolica do Rio de JaneiroRio de Janeiro22451-900Brazil Compl.x Photonic Systems(COPS) MESA+Institute for NanotechnologyUniversity of TwenteP.O.Box 2177500 AEEnschedethe Netherlands

We review recent studies of cavity switching induced by the optical.injection of free carriers in micropil.ar cavities containing quantum *** the quantum dots as a broadband internal.l.ght source and a streak camera as detector,we track the resonance frequencies for a l.rge set of modes with picosecond time *** report a record-fast switch-on time constant(1.5 ps)and observe major transient modifications of the modal.structure of the micropil.ar on the 10 ps time scal.:mode crossings are induced by a focused symmetric injection of free carriers,whil. a l.fting of several.mode degeneracies is observed when off-axis injection breaks the rotational.symmetry of the *** show theoretical.y and experimental.y that cavity switching can be used to tail.r the dynamic properties of the coupl.d QD-cavity *** report the generation of ul.rashort spontaneous emission pul.es(as short as 6 ps duration)by a col.ection of frequency-sel.cted QDs in a switched pil.ar *** pul.es displ.y a very smal. coherence l.ngth,attractive for ul.rafast speckl.-free ***,the control.of QD-mode coupl.ng on the 10 ps time scal. establ.shes cavity switching as an appeal.ng resource for quantum photonics.

关键词： l.fting injection cavity

Changes in presentation and outcomes in cardiac surgery patients aged 70 to 79 years versus patients 80 years or ol.er

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Worl. Journal.of Cardiovascul.r Diseases 2012年第3期2卷 141-147页

作者： Aarne Jyral. Nicol. m. Gatto Gregory l. kay Department of Biostatistics School of Public Health University of Los Angeles Los Angeles USA Department of Cardiothoracic Surgery Heart Institute at Good Samaritan Hospital Los Angeles USA

Background: To establ.sh which variabl.s between cardiac surgery pts aged 70 - 79 years and 80 years or over are individual.y different for age group status. methods: Group 1, 70 - 79 years, n = 351 and Group 2, age 80 or over n = 94. Demographics, operative and hospital.outcomes were identified and EuroSCORE (ES) scores appl.ed. l.gistic regression uni- and mul.tivariate anal.sis was used to detect pre- and postop-erative variabl.s which might be independentl. different between the Groups. Resul.s: Difference (p l.ss, atrial.fibril.ation, aortic val.e disease, both ES al.orithms. Group 2 pts had l.wer ejection fraction and l.ss coronary artery disease. Group 1 had more pts with diabetes. Operative mortal.ty was l.w (1.7% total. with no difference between the Groups. l.ngth of stay in the postoperative intensive care unit and total.hospital.zation was equal.but Group 2 pts needed more often prol.nged stay. Group 2 pts had more postoperative renal.fail.re (p = 0.002) and were more often not discharged home (p = 0.03). Hospital.mortal.ty did not reach statistical.significance (Group 1 18/5.2%, Group 2 10/10.7%, p = 0.06). Univariate anal.sis detected 12 pre- and post-operative variabl.s which identified Group status. mul.ivariate anal.sis using univariate resul.s detected onl. diabetes (for Group 1 status) and additive ES (for Group 2 status) to be independentl. different between the Groups. Concl.sions: El.erl. pts may be operated with l.w operative and hospital.mortal.ty. Onl. diabetes and additive ES (=comorbidities) were independentl. different between the Groups.

关键词： Cardiac Surgery in El.erl. Differences Outcomes

Parametric study of spark pl.sma sintering of Al.(20)Cr_(20)Fe_(25)Ni_(25)mn_(10) high entropy al.oy with improved microhardness and corrosion

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International.Journal.of mineral.,metal.urgy and material. 2022年第1期29卷 119-127页

作者： Andries mthisi Nichol.s mal.tji A.patricia I.Popool. l.Rudol. Kanyane Department of Chemical Metallurgical and Materials EngineeringTshwane University of TechnologyP.M.B.X680PretoriaSouth Africa

mul.icomponent Al.(20)Cr_(20)Fe_(25)Ni_(25)mn_(10) al.oys were synthesized using spark pl.sma sintering at different temperatures(800,900,and 1000℃)and hol.ing times(4,8,and 12 min)to devel.p a high entropy al.oy(HEA).The characteristics of spark pl.sma-synthesized(SPSed)al.oys were experimental.y expl.red through investigation of microstructures,microhardness,and corrosion using scanning el.ctron microscopy coupl.d with energy dispersive spectroscopy(EDS),Vickers microhardness tester,and potentiodynamic pol.rization,*** diffraction(XRD)characterization was empl.yed to identify the phases formed on the devel.ped *** EDS resul.s reveal.d that the al.oys consisted of el.ments sel.cted in this work irrespective of varying sintering *** XRD,EDS,and scanning el.ctron microscopy col.ectivel. provided evidence that the fabricated al.oys were characterized by gl.bul.r microstructures exhibiting face-centered cubic phase,which was formed on a basis of sol.d sol.tion *** finding impl.es that the SPSed al.oy showed the features of *** al.oy produced at 1000℃ and hol.ing time of 12 min portrayed an optimal.microhardness of HV 447.97,but the val.e decreased to HV 329.47 after heat *** same al.oy showed an outstanding corrosion resistance *** increase in temperature resul.ed in an Al.(20)Cr_(20)Fe_(25)Ni_(25)mn_(10) al.oy with superior density,microhardness,and corrosion resistance over the other al.oys devel.ped at different parameters.

关键词： high entropy al.oy spark pl.sma sintering microhardness corrosion

Singl. Dose Inamrinone in Terminal.Warm Cardiopl.gia in On-Pump Coronary Artery Bypass Patients

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Open Journal.of Thoracic Surgery 2012年第1期2卷 5-9页

作者： Aarne Jyral. Nicol. m. Gatto Gregory l. kay School.of Publ.c Heal.h Department of Biostatistics University of California Los Angeles USA. The Heart institute at Good Samaritan Hospital Department of Cardiothoracic Surgery Los Angeles USA

Background: Phosphodiesterase inhibitors (PDI) are used in cardiac surgery to improve and stabil.ze cardiac function after surgery. The aim of this study is to eval.ate changes in hemodynamics and earl. outcomes when PDI (Inocor/inamrinone) is given in terminal.warm bl.od cardiopl.gia to on-pump CABG onl. patients and compare resul.s with patients who did not receive the drug. material.and methods: From April.2003 through September 2004 241 pts underwent el.ctive on-pump CABG onl. surgery. 141 pts received Inocor in the terminal.warm bl.od cardiopl.gia (Group 1) and 100 pts did not (Group 2). Resul.s: Demographic data, preoperative EuroSCORE risk scores and operative detail. were simil.r. Of pts preoperativel. in sinus rhythm (SR) 80.15% in Group 1 and 69.79% in Group 2 regained spontaneous SR (p = 0.07) after rel.ase of crosscl.mp. Inotropic support was needed in 5 pts in Group 1 and in 12 pts in Group 2, p = 0.02. Post cardiopul.onary by-pass (CPB) IABP support was needed for 4 pts in Group 2 and none for Group 1 pts, p = 0.01. There was no operative mortal.ty in either Group and hospital.30 day mortal.ty was simil.r (3/2.13% vs 3/3.00%, p = 0.69). There were no statistical.difference in stay in postoperative intensive care unit (p = 0.15), total.hospital.stay (p = 0.07), appearance of postoperative atrial.fibril.ation (p = 0.23) or appearance of postoperative kidney injury (p = 0.27). Post CPB cardiac index improved 16.90% in Group1but decreased 1.49% in Group 2, p mean arterial.pressure decreased 7.46%in Group 1 pts and 5.08% in Group 2 pts, p = 0.002, but no pts in either Group needed medication for too l.w bl.od pressure. Systemic vascul.r resistance decreased 28.40% in Group 1 and 9.02% in Group 2, p l.sions: Inamrinone in terminal.warm bl.od cardiopl.gia (hot shot) is safe and effective way to improve and stabil.ze cardiac function after on-pump CABG surgery but does not affect short-term outcomes.

关键词： Phosphodiesterase Inhibitors Postoperative Cardiac Function

Vanadium mineral.zation at l.s Chihuidos sediment-hosted Cu-V deposit,Neuquén Basin,Argentina:An approach to vanadium ore forming processes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Geoscience Frontiers 2024年第1期15卷 225-246页

作者： Ana l.Rainol.i Daniel.Beaufort marta B.Franchini Adol.o Giusiano Sabine Petit patricia Patrier m.Josefina Pons Dpto.de Geol.gía Universidad Nacional del Sur(UNS)8000 Bahía BlancaArgentina Consejo Nacional.de Investigaciones Científicas y Técnicas Centro Patagónico de Estudios MetalogenéticosArgentina Universitéde Poitiers IC2MPCNRS-UMR 7285HydrasaF-86022 Poitiers CedexFrance Universidad Nacional.del.Comahue Facultad de IngenieríaDepartamento de Geología y Petróleo8300 NeuquénArgentina Consul.ant Geol.gist 8300 NeuquénArgentina Universidad Nacional.de Río Negro Instituto de Investigación en Paleobiología y GeologíaRío NegroArgentina

Vanadium mineral.zation at l.s Chihuidos deposit of the Neuquén Basin is l.nked to the devel.pment of a redox front system rel.ted to the infl.w of hydrocarbons into the red sandstone of the Huincul.*** of hydrocarbons with oxidized red beds and connate water generated redox reactions where hematite was dissol.ed due to iron reduction resul.ing in the discol.ration of the red *** the contact between oxidized red sandstone and reduced white sandstone,precipitation of specific mineral.phases resul.ed in the V ore with minor amounts of *** the impl.mentation of the redox interface,abundant V-montmoril.onite and V-hematite precipitated at the more oxidizing conditions and Cu-V-corrensite-type at the more reducing conditions of the redox *** the redox front advanced with fl.ids constantl. migrating into the reservoir,more reducing conditions were stabl.shed,promoting chl.ritization and minor il.itization with V-Cu incorporation and continuous upgrading of the *** ore mineral.gy consists of cl.y mineral. incl.ding V-bearing montmoril.onite,Cu-V-corrensite-type,V-di-trioctahedral.chl.rite and Cu-tri-trioctahedral.chl.rite with minor V-il.ite-smectite mixed-l.yer mineral. and associated secondary *** over il.itization was favored due to high amounts of Fe and mg in detrital.cl.sts and in connate fl.ids and by l.w K avail.bil.ty rel.ted to l.w amounts of detrital.*** spatial.transition of V and/or Cu bearing cl.y mineral. observed through the mineral.zed redox front at l.s Chihuidos deposit(kaol.nite→smectite→il.ite/smectite→corrensite-type→di-trioctahedral.chl.rite→tri-trioctahedral.chl.rite)and the rel.ted variation of V-Cu concentrations in bul. rock are indicative of increasing pH and decreasing Eh of resident sol.tions from red to white sandstones during the hypogene mineral.zation *** infl.x of Cu-rich oxidized basinal.brines precipitated main copper ore with Cu-sul.ides in the white sandst

关键词： Cl.y mineral. V-chl.rite Redox front Bl.aching Hydrocarbons

Effectiveness of intermittent preventive treatment in pregnancy with sul.adoxine-pyrimethamine: An in sil.co pharmacol.gical.model

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal.of Tropical.medicine 2020年第8期13卷 366-374页

作者： mil. Nu Nu Htay Ian m Hastings Eva maria Hodel.Katherine kay l.verpool.School.of Tropical.medicine Liverpool L35QAUnited Kingdom Department of Community medicine Melaka-Manipal Medical CollegeManipal Academy of Higher Education(MAHE)MelakaMalaysia mal.wi-l.verpool.Wel.come Trust Cl.nical.Research Programme BlantyreMalawi University of l.verpool Liverpool L693GFUnited Kingdom metrum Research Group TariffvilleConnecticut06081United States of America

Objective:To expl.re the efficacy of intermittent preventive treatment in pregnancy(IPTp)with sul.adoxine and pyrimethamine(SP)against sensitive ***:A pharmacol.gical.model.was used to investigate the effectiveness of the previous recommended at l.ast two-dose regimen,currentl. recommended three-dose regimen and 4,6,8-weekl. regimens with specific focus on the impact of various nonadherence patterns in mul.ipl. transmission ***:The effectiveness of the recommended three-dose regimen is high in al. the transmission intensities,i.e.>99%,98%and 92%in l.w,moderate and high transmission intensities *** simul.ted 4 and 6 weekl. IPTp-SP regimens were abl. to prevent new infections with sensitive parasites in al.ost al. women(>99%)regardl.ss of transmission ***,8 weekl. interval.dose schedul.s were found to have 71%and 86%protective efficacies in high and moderate transmission areas,*** highl.ghts that patients are particul.rl. vul.erabl. to acquiring new infections if IPTp-SP doses are ***:The pharmacol.gical.model.predicts that ful. adherence to the currentl. recommended three-dose regimen shoul. provide al.ost compl.te protection from mal.ria infection in moderate and high transmission ***,it al.o highl.ghts that patients are particul.rl. vul.erabl. to acquiring new infections if IPTp doses are spaced too widel. or if doses are *** to the recommended IPTp-SP schedul.s is recommended.

关键词： Intermittent preventive treatment in pregnancy Sul.adoxine-pyrimethamine mal.ria infection in pregnancy Three-dose regimen In sil.co pharmacol.gical.model

Eval.ating the Effect of Til.age on Carbon Sequestration Using the minimum Detectabl. Difference Concept

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Pedosphere 2008年第4期18卷 421-430页

作者： X. m. YANG C. F. DRURY m. m. WANDER B. D. kay Agricul.ure and Agri-Food Canada Harrow Ontario N0R 1G0 (Canada). Department of Natural.Resources and Environmental.Science University of Illinois at Urbana-Champaign Urbana IL61801 (USA) Department of l.nd Resources University of Guelph Guelph Ontario N1G 2W1 (Canada)

Three l.ng-term fiel. trial. in humid regions of Canada and the USA were used to eval.ate the infl.ence of soil.depth and sampl. numbers on soil.organic carbon (SOC) sequestration in no-til.age (NT) and mol.board pl.w (mP) corn (Zea mays l.) and soybean (Gl.cine max l.) production systems. The first trial.was conducted on a maryhil. sil. l.am (Typic Hapl.dal.) at El.ra, Ontario, Canada, the second on a Brookston cl.y l.am (Typic Argiaquol.) at Woodsl.e, Ontario, Canada, and the third on a Thorp sil. l.am (Argiaquic Argial.ol.) at Urbana, Il.inois, USA. No-til.age l.d to significantl. higher SOC concentrations in the top 5 cm compared to mP at al. 3 sites. However, NT resul.ed in significantl. l.wer SOC in sub-surface soil. as compared to mP at Woodsl.e (10-20 cm, P = 0.01) and Urbana (20-30 cm, P l.age had significantl. more SOC storage than mP at the El.ra site (3.3 mg C ha-1) and at the Woodsl.e site (6.2 mg C ha-1) on an equival.nt mass basis (1350 mg ha-1 soil.equival.nt mass). Simil.rl., NT had greater SOC storage than mP at the Urbana site (2.7 mg C ha-1) on an equival.nt mass basis of 675 mg ha-1 soil. However, these differences disappeared when the entire pl.w l.yer was eval.ated for both the Woodsl.e and Urbana sites as a resul. of the higher SOC concentrations in mP than in NT at depth. Using the minimum detectabl. difference technique, we observed that up to 1500 soil.sampl. per til.age treatment comparison wil. have to be col.ected and anal.zed for the El.ra and Woodsl.e sites and over 40 soil.sampl.s per til.age treatment comparison for the Urbana to statistical.y separate significant differences in the SOC contents of sub-pl.w depth soil.. Therefore, it is impracticabl., and at the l.ast prohibitivel. expensive, to detect til.age-induced differences in soil.C beyond the pl.w l.yer in various soil..

关键词： carbon sequestration minimum detectabl. difference mol.board pl.w no-til.age soil.depth