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Heterosis in age-specific selected populations of a seed beetle： Sex differences in longevity and reproductive behavior

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Insect Science 2015年第2期22卷 295-309页

作者： Biljana Stojkovic Mirko Dordevia Jelena Jankovic Uros Savkovic nikola Tucic Department of Evolutionary Biology Institute for Biological Research 'Sinisa Stankovie' University of Belgrade Institute of Zoology Faculty of Biology University of Belgrade Belgrade Serbia

We tested mutation accumulation hypothesis for the evolution of senescence using short-lived and long-lived populations of the seed-feeding beetle, Acanthoscelides obtectus （Say）, obtained by selection on early- and late-life for many generations. The expected consequence of the mutation accumulation hypothesis is that in short-lived pop- ulations, where the force of natural selection is the strongest early in life, the late-life fitness traits should decline due to genetic drift which increases the frequency of mutations with deleterious effects in later adult stages. Since it is unlikely that identical deleterious mutations will increase in several independent populations, hybrid vigor for late-life fit- ness is expected in offspring obtained in crosses among populations selected for early-life fitness traits. We tested longevity of both sexes, female fecundity and male reproductive behavior for hybrid vigor by comparing hybrid and nonhybrid short-lived populations. Hybrid vigor was confirmed for male virility, mating speed and copulation duration, and longevity of both sexes at late ages. In contrast to males, the results on female fecundity in short-lived populations did not support mutation accumulation as a genetic mechanism for the evolution of this trait. Contrary to the prediction of this hypothesis, male mating ability indices and female fecundity in long-lived populations exhibited hybrid vigor at all assayed age classes. We demonstrate that nonhybrid long-lived populations diverged randomly regarding female and male reproductive fitness, indicating that sexually antag- onistic selection, when accompanied with genetic drift for female fecundity and male virility, might be responsible for overriding natural selection in the independently evolving long-lived populations.

关键词： ageing antagonistic selection drift experimental evolution inbreeding depression mutation accumulation

Cerebral misery perfusion due to carotid occlusive disease

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Stroke & Vascular Neurology 2017年第2期2卷 88-93页

作者： Mohana Maddula nikola Sprigg Philip M Bath Sunil Munshi Acute Stroke Unit Tauranga HospitalTaurangaNew Zealand Division of Clinical Neuroscience University of NottinghamNottinghamUK Department of Stroke Nottingham University Hospitals NHS TrustNottinghamUK

Purpose Cerebral misery perfusion(CMP)is a condition where cerebral autoregulatory capacity is exhausted,and cerebral blood supply in insufficient to meet metabolic *** present an educational review of this important condition,which has a range of clinical *** A non-systematic review of published literature was undertaken on CMP and major cerebral artery occlusive disease,using Pubmed and *** Patients with CMP may present with strokes in watershed territories,collapses and transient ischaemic attacks or episodic movements associated with an orthostatic *** positron emission tomography is the gold standard investigation for misery perfusion,advanced MRI is being increasingly used as an alternative investigation *** presence of CMP increases the risk of *** addition to the devastating effect of stroke,there is accumulating evidence of impaired cognition and quality of life with carotid occlusive disease(COD)and misery *** evidence for revascularisation in the setting of complete carotid occlusion is *** management constitutes careful blood pressure management while addressing other vascular risk *** The evidence for the management of patients with COD and CMP is discussed,together with recommendations based on our local *** this review,we focus on misery perfusion due to *** Patients with CMP and COD may present with a wide-ranging clinical phenotype and therefore to many *** identification of patients with misery perfusion may allow appropriate management and focus on strategies to maintain or improve cerebral blood flow,while avoiding potentially harmful treatment.

关键词： perfusion carotid impaired

NSVS 2569022:a peculiar binary among W UMa stars with extremely small mass ratios

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Research in Astronomy and Astrophysics 2018年第10期18卷 123-130页

作者： Diana P.Kjurkchieva Velimir A.Popov nikola I.Petrov Department of Physics and Astronomy Shumen University Institute of Astronomy and NAO Bulgarian Academy of Sciences

Photometric observations of the W UMa binary NSVS 2569022 are presented. The light curve solution reveals that both components are of F spectral type （temperatures T1 = T2 = 6100 K）. NSVS 2569022 undergoes a total eclipse of W subtype and the mass ratio is well-determined. Its extremely small value of only 0.077 implies that the target will probably experience instability and a possible merger. This value ranks NSVS 2569022 in sixth place among binaries with the smallest mass ratio. Based on an empirical relation of ＂period - total mass＂ for low mass-ratio binaries, we estimate the global parameters of NSVS 2569022： masses M1 = 1.17 M⊙ and M2 = 0.09 M⊙; radii R1 = 1.19 R⊙ and R2 = 0.38 R⊙; luminosities L1 = 1.73 L⊙ and L2 = 0.17L⊙. An analysis of the characteristics of binaries with extremely low-mass ratios is made. NSVS 2569022 turns out to be a peculiar binary among W UMa stars with extremely small mass ratios due to its unexpectedly small fill-out factor of only 0.014 （slightly overcontact configuration）.

关键词： binaries eclipsing - binaries close - stars fundamental parameters - stars individual(NSVS 2569022)

New observations and transit solutions of the inflated exoplanets HAT-P-40b and HAT-P-51b

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Research in Astronomy and Astrophysics 2021年第2期21卷 157-160页

作者： Diana P.Kjurkchieva nikola I.Petrov Velimir A.Popov Department of Physics and Astronomy Shumen University115 Universitetska str.9700 ShumenBulgaria Institute of Astronomy and NAO Bulgarian Academy of SciencesTsarigradsko shossee 721784 SofiaBulgaria

We present high-precision photometric observations of the transiting exoplanets HAT-P-40 b and HAT-P-51 b by the Rozhen 2-m *** newly-observed transit of HAT-P-40 b is the first one with a complete *** orbital periods of the two targets were *** modeled the observed transits and found bigger stellar radii than those derived from the stellar *** planet radii of HATP-40 b and HAT-P-51 b obtained from our transit solutions are bigger than the values calculated by the empirical relations for Jupiter-mass and Saturn-mass planets *** values reveal the highlyinflated nature of the two targets,especially that of HAT-P-51 *** established that the best transit solutions correspond to a quadratic limb-darkening *** fitted limb-darkening coefficients of HAT-P-40 are close to the theoretical ones while those of HAT-P-51 are a little *** precise astrometric Gaia distances of the two targets are smaller by 6%–7%than the calculated values from the stellar *** propose the Gaia distances to be used for improvement of the stellar models as well as for more reliable calculation of the parameters of the known exoplanets.

关键词： (Stars )planetary systems-techniques photometric-Stars individual(HAT-P-40 and HAT-P-51)

ON CRITERIA FOR STARLIKENESS AND CONVEXITY OF ANALYTIC FUNCTIONS

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Acta Mathematica Scientia 2004年第4期24卷 597-602页

作者： Vikramaditya Singh nikola Tuneski Faculty of Mechanical Engineering Karpos Ⅱ b.b. 1000 Skopje Republic of MacedoniaFaculty of Mechanical Engineering Karpos Ⅱ b.b. 1000 Skopje Republic of Macedonia

In this paper the authors study (1-γ+zf(?)(z)/f'(z))/(zf'(z)/f(z)) as a criteria for starlikeness and convexity. Sharp upper bound of |α2| and of the Fekete-Szego functional |α3-μα22| is given for a class of anal... 详细信息

关键词： Starlike convex criteria Fekete-Szego

Observations and light curve solutions of a selection of middle-contact W UMa binaries

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Research in Astronomy and Astrophysics 2018年第4期18卷 105-114页

作者： Diana Petrova Kjurkchieva Velimir Angelov Popov Doroteya Lyubenova Vasileva nikola Ivanov Petrov Department of Physics Shumen University IRIDA Observatory Rozhen NAO Institute of Astronomy and NAO Bulgarian Academy of Sciences

Photometric observations in Sloan g′and i′ bands of W UMa binaries NSVS 4340949,T-Dra0–00959,GSC 03950–00707,NSVS 4665041,NSVS 4803568,MM Peg,MM Com and NSVS4751449 are *** light curve solutions revealed that the components of each target are of G and K spectral *** binaries of the sample have middle-contact configurations whose fillout factors are within the range 0.2–*** only exception is NSVS 4751449 which is in deeper contact（fillout factor of 0.55）.It precisely obeys the relation between mass ratio and fillout factor for deep,low mass ratio overcontact *** of the eclipses of almost all targets（except MM Peg）is an occultation and their photometric mass ratios and solutions could be accepted with *** found that the target components have almost equal temperatures but differ considerably in size and *** components of the partially-eclipsed MM Peg have close *** solutions reveal that NSVS 4340949,T-Dra0–00959,NSVS 4803568 and MM Com are of W subtype while GSC 03950–00707,NSVS 4665041,MM Peg and NSVS 4751449 are of A *** subclassification is well-determined for all totallyeclipsed *** targets confirm the trends in which W-subtype systems have smaller periods and lower temperatures than A subtype binaries.

关键词： binaries close — binaries eclipsing — stars fundamental parameters — stars late-type

Photometric observations and light curve solutions of the W UMa stars NSVS 2244206,NSVS 908513,CSS J004004.7+385531 and VSX J062624.4+570907

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Research in Astronomy and Astrophysics 2016年第9期16卷 15-22页

作者： Diana Petrova Kiurkchieva Velimir Angelov Popov Doroteya Lyubenova Vasileva nikola Ivanov Petrov Department of Physics Shumen University115Universitetska Str.1712 ShumenBulgaria IRIDA Observatory 17A Prof.Asen Zlatarov Str.SofiaBulgaria Institute of Astronomy and National Astronomical Observatory Bulgarian Academy of Sciences72Tsarigradsko Shose Blvd.1784 SofiaBulgaria

Photometric observations in Sloan 9＇ and i＇ bands of four W UMa stars, NSVS 2244206, NSVS 908513, CSS J004004.7＋385531 and VSX J062624.4＋570907, are presented. The light curve solutions reveal that all targets have overcontact configurations with fillout factors within 0.15-0.26. Their components are G-K spectral types and are almost in thermal contact. They are also relatively close in size and luminosity： the radius ratios r2/r1 are within 0.75-0.90; the luminosity ratios 12/11 are within 0.53-0.63. The results of the light curve solution of CSS J004004.7＋385531 imply the weak limb-darkening effect of its primary component and possible presence of additional absorbing features in the system.

关键词： methods data analysis -- stars fundamental parameters -- stars binaries eclipsing individ-ual (NSVS 2244206, NSVS 908513, CSS J004004.7+385531, VSX J062624.4+570907)

Erythrocytic transglutaminase inhibition hemolysis at presentation of celiac disease

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World Journal of Gastroenterology 2010年第44期16卷 5647-5650页

作者： Petar Ivanovski Dimitrije Nikoli nikola Dimitrijevi Ivan Ivanovski Vojislav Perii Pediatric Clinic of the University Children's Hospital Medical Faculty University of Belgrade Department of Medical Student Research Medical Faculty University of Belgrade

Celiac disease (CD) is a common autoimmune *** it was considered to be a rare childhood disorder,but is actually considered a relatively common condition,present at any age,which may have multiple complications and *** disorders of the disease are not *** these disorders,the most frequently reported are anemias as a result of iron deficiency,often associated with folate and/or B12 *** caused by hemolysis are very rarely reported in celiac *** 11-year-old girl with a previous uneventful medical history presented with severe hemolytic *** was Coombs negative,accompanied by inappropriate low reticulocyte count,despite exaggerated bone marrow hyperplasia of the erythroid precursors which showed normal *** for recent infections,including EpsteinBarr virus,parvovirus B19,cytomegalovirus and mycoplasma,were all *** of serum IgA,IgG and IgM,were all within normal ranges for *** anti-DNA,antinuclear,antineutrophil cytoplasmic,antimicrosomal,antithyroglobulin,and antimitochondrial antibodies and lupus anticoagulants,was *** was also negative for human immunodeficiency *** therapy with corticosteroids and intravenous immunoglobulin *** was serendipitously discovered upon screening for anti-tissue transglutaminase *** disease was confirmed by biopsy of the small intestine *** patient recovered with gluten-free diet.A unique case of CD is *** should be serologically screened in each patient with Coombs negative "immune"hemolytic anemia,particularly if accompanied by "reticulocytopenia".A new hemolytic mechanism and very speculative explanation for "reticulocytopenia"are discussed.

关键词： Celiac disease Tissue transglutaminase Antibodies Hemolytic anemia Gluten free diet

Childhood brucellosis:Review of 317 cases

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Asian Pacific Journal of Tropical Medicine 2015年第12期8卷 1000-1005页

作者： Mile Bosilkovski Ljiljana Krteva Sonja Caparoska nikola Labacevski Mile Petrovski Medical Faculty Ss Cyril and Methodius' University University Clinic for Infectious Diseases and Febrile Conditions Institute for Clinical Pharmacology University Clinic for Pediatric Surgery

Objective:To describe the main epidemiological,clinical,and laboratory features,treatment options and outcome in children with ***:Retrospectively evaluated data were obtained from 317 pediatric patients with brucellosis that were treated at the University Clinic for Infectious Diseases and Febrile Conditions in Skopje,during the period from 1989 to *** medical records and follow-up protocols were used for ***:Childhood brucellosis composed 317(18.7%) of 1 691 patients with *** patients were median 9 years old,ranging from 7 months to 14 years,and 201(63.4%) were *** history was present in 197(62.1%),and direct contact with animals occurred in 140(44.2%) of the *** dominant manifestations were fever in 248(78.2%),joint pain in228(71.9%) and hepatomegaly in 216(68.1%).Organ affection was present in 206(65.0%)of the *** hundred and six(33.4%) of the patients were treated with combination composed of *** 211(66.6%) with three antimicrobial *** were registered in 21(6.6%).and therapeutic failures in 3(0.9%) of the ***:In endemic regions childhood brucellosis represents a significant part of human *** spectrum of clinical manifestations,frequent affection of various organ systems and possibility of relapses show that brucellosis could be a serious disease in this age *** presence of fever,joint pain,sweating,and affection of various systems in children from endemic regions should alert pediatricians for the possibility of brucellosis.

关键词： Brucellosis Children Clinical manifestation Treatm