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Theoretical and experimental assessment of a novel method to establish the complete measurement range of the calorimeter and its limit of detection and quantification

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Chinese Journal of Chemical Engineering 2022年第4期35卷 466-473页

作者： vesna Krstic af005 Mining and Metallurgy Institute Bor Zeleni Bulevar 3519210 BorSerbia af010.University of Belgrade Technical Faculty BorVJ 1219210 BorRepublik of Serbia

For determining the accuracy of a calorimeter over the instrument’s entire measuring range,a novel method has been *** this new approach,(a)benzoic acid(C_(6)H_(5)CO_(2)H) as a certified reference material(CRM),(b)SiO_(2) and(c)a mixture of CRM benzoic acid and SiO_(2) have been *** illustrate the essential difference between 1)the novel analytical method for control of the entire measurement range and 2)the calorimeter calibration,both applications of benzoic acid(BA)have been *** experimental result showed that BA was successfully used to check the whole calorimeter measurement *** results also showed that the same new method was successfully applied to determine the limit of detection and quantification.A new instrument testing process and a new measurement technique have thus been *** this way,the cost of using CRM to control the accuracy of measuring the entire measuring range of the calorimeter,as shown in this paper,is *** requirements of the ISO/IEC 17025:2017 standard are ***/IEC 17025:2017,together with ISO 9001:2015(quality management systems),ISO 14001:2015(relate to environmental protection)and ISO45001:2018(occupational safety),constitute an integrated quality system by which a testing laboratory may also accredit.

关键词： Benzoic acid Certified reference material The limit of detection/quantification Measurement range Quality control Calorimeter Environmental protection

Influences of synthesis methods and modifier addition on the properties of Ni-based catalysts supported on reticulated ceramic foams

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International Journal of Minerals,Metallurgy and Materials 2014年第8期21卷 806-812页

作者： vesna Nikolic Zeljko Kamberovic Zoran Antic Marija Korac Miroslav Sokic vesna Maksimovic Innovation Center of the Faculty of Technology and Metallurgy University of Belgrade Karnegijeva 4 11120 Belgrade Serbia Faculty of Technology and Metallurgy University of Belgrade Karnegijeva 4 11120 Belgrade Serbia Innovation Center of the Faculty of Chemistry University of Belgrade Studentski trg 12-16 11000 Belgrade Serbia Institute for Technology of Nuclear and other Raw Materials Bulevar Frans d'Eperea 86 11000 Belgrade Serbia Institute for Nuclear Sciences ‘Vinca’ Mike Petrovica Alasa 12-14 11001 Belgrade Serbia

A method of synthesizing Ni-based catalysts supported on α-Al2O3-based foams was developed. The foams were impregnated with aqueous solutions of metal chlorides under an air atmosphere using an aerosol route. Separate procedures involved calcination to form oxides and drying to obtain chlorides on the foam surface. The synthesized samples were subsequently reduced with hydrogen. With respect to the Ni/Al2O3 catalysts, the chloride reduction route enabled the formation ofa Ni coating without agglomerates or cracks. Further research included catalyst modification by the addition of Pd, Cu, and Fe. The influences of the additives on the degree of reduction and on the low-temperature reduction effectiveness （533 and 633 K） were examined and compared for the catalysts obtained from oxides and chlorides. Greater degrees of reduction were achieved with chlorides, whereas Pd was the most effective modifier among those investigated. The reduction process was nearly complete at 533 K in the sample that contained 0.1wt% Pd. A lower reduction temperature was utilized, and the calcination step was avoided, which may enhance the economical and technological aspects of the developed catalyst production method.

关键词： catalysts nickel ceramic foams modification aerosol process catalytic properties

An Application of the Shark Skin Denticle Geometry for Windbreak Fence Design and Fabrication

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Journal of Bionic Engineering 2017年第3期14卷 579-587页

作者： Ivana Bajsanski vesna Stojakovic Bojan Tepavcevic Marko Jovanovic Dejan Mitov Department of Architecture Faculty of Technical Sciences University of Novi Sad Trg Dositeja Obradoviea 6 21000 Novi Sad Serbia

Windbreak fences in open and urban areas can be used to effectively reduce the wind velocity. In this paper we examine how the geometrical shape of the windbreak fence can optimally mitigate wind velocity. We propose an approach for windbreak fence design based on a bionic parametric model of the shark skin denticle geometry, which improves the reduction of the wind velocity around and behind the windbreak fences. The generative model was used to estimate improvements by variations in the parameters of the fence panel＇s geometrical shape, inspired by shark skin denticles. The results of the Computational Fluid Dynamics （CFD） analysis indicates that the fence surface inspired by shark skin performs much better than both flat and cor- rugated surfaces. Taking into account the complex geometry of the surface inspired by shark skin denticles, we propose a fab- rication process using an expanded polystyrene foam （EPS） material, created using an industrial robot arm with a hot-wire tool. Creating EPS moulds for the shark skin denticle panels allows for a richer variety material to be used in the final design, leading both to higher efficiency and a more attractive design.

关键词： bioinspiration shark skin denticle windbreak fence design generative models CFD

COMMON FIXED POINT OF GENERALIZED WEAKLY CONTRACTIVE MAPS IN PARTIAL METRIC SPACES

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Acta Mathematica Scientia 2014年第4期34卷 1345-1356页

作者： vesna COJBAIC RAJIC Stojan RADENOVIC Sunny CHAUHAN Faculty of Economics University of BelgradeKamenicka 611000 BeogradSerbia Faculty of Mechanical Engineering University of BelgradeKraljice Marije 1611 120 BeogradSerbia R. H. Government Postgraduate College Kashipur-244 713 (U.S. Nagar)UttarakhandIndia

In this paper, using the context of complete partial metric spaces, some common fixed point results of maps that satisfy the generalized （ψ, Ф）-weak contractive conditions are obtained. Our results generalize, extend, unify, enrich and complement many existing results in the literature. Example are given showing the validaty of our results.

关键词： Common fixed point lower semi-continuous function weak (ψ, Ф)-contraction partial metric space

Crosstalk between dietary patterns,obesity and nonalcoholic fatty liver disease

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World Journal of Gastroenterology 2022年第27期28卷 3314-3333页

作者： Danijela Ristic-Medic Joanna Bajerska vesna Vucic Group for Nutritional Biochemistry and Dietology Centre of Research Excellence in Nutrition and MetabolismInstitute for Medical ResearchNational Institute of Republic SerbiaBelgrade PO Box 102Serbia Department of Human Nutrition and Dietetics PoznańUniversity of Life SciencesPoznań60-624Poland

The prevalence of nonalcoholic fatty liver disease(NAFLD)is rising worldwide,paralleling the epidemic of *** liver is a key organ for the metabolism of proteins,fats and *** types of fats and carbohydrates in isocaloric diets differently influence fat accumulation in the liver ***,nutrition can manage hepatic and cardiometabolic complications of *** moderately reduced caloric intake,which leads to a weight loss of 5%-10%of initial body weight,is effective in improving liver steatosis and surrogate markers of liver disease *** dietary patterns,the Mediterranean diet mostly prevents the onset of ***,this diet is also the most recommended for the treatment of NAFLD ***,clinical trials based on the dietary interventions in NAFLD patients are *** there are only a few studies examining dietary interventions in clinically advanced stages of NAFLD,such as active and fibrotic steatohepatitis,the optimal diet for patients in these stages of the disease must still be *** this narrative review,we aimed to critically summarize the associations between different dietary patterns,obesity and prevention/risk for NAFLD,to describe specific dietary interventions’impacts on liver steatosis in adults with NAFLD and to provide an updated overview of dietary recommendations that clinicians potentially need to apply in their daily practice.

关键词： Nonalcoholic fatty liver disease Dietary patterns Obesity Diet Mediterranean diet Nutrition Treatment Clinical guidance

Context dependent song-flight performance and timing in the Black-headed Bunting(Emberiza melanocephala)

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Avian Research 2022年第4期13卷 477-486页

作者： Sanja Barisic Davor Cikovic vesna Tutis Jelena Kralj Herbert Hoi Institute of Ornithology Croatian Academy of Sciences and ArtsZagrebGunduliceva 2410000ZagrebCroatia Konrad Lorenz Institute of Ethology Department of Interdisciplinary Life SciencesUniversity of Veterinary Medicine ViennaSavoyenstraße 1A1160ViennaAustria

Many songbirds produce song-flights;however,the function,vocal and motor characteristics,as well as the diel and seasonal variation of song-flight in songbirds remain not well ***,we studied two types of song-flight in male Black-headed Buntings(Emberiza melanocephala),the Moth—a standard,i.e.,perch song produced during a horizontal flight,and the Towering—a specifically structured song produced during a complex ascending and descending *** perch song,used during Moth flight,has already been described,here we provide the first description and sonogram representation of the more elaborate and less stereotyped Towering *** males started to perform Moth song-flights as soon as they arrived at the breeding site,Towering did not start before the female *** usually delivered spontaneous Moth song-flights before chasing rivals or undertaking aerial fights,suggesting Moth is directed towards conspecific males and serves as a threat ***,playback of conspecific perch songs triggered males to approach the loudspeaker with Moth *** Towering started after females arrived at the breeding site,suggesting the Towering is directed towards conspecific *** detected a seasonal difference in the peak Towering rate between forenoon and afternoon,suggesting that Towerings performed at different times of the day have different *** Towerings were strongly positively related to the number of fertile females at the breeding site,while afternoon Towerings peaked very early in the breeding season and coincided with the number of females at the breeding site before the onset of *** results provide evidence that birds can direct different types of song-flight towards different receivers and suggest the possibility that time of the day determines the context of the display,namely to attract social mates or solicit *** work is needed to account for the effect of between male vari

关键词： Fertilisation probability Mate attraction Moth song-flight Towering song-flight

Initial nucleation of amorphous Si–B–C–N ceramics derived from polymer-precursors

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Journal of Materials Science & Technology 2019年第12期35卷 2851-2858页

作者： Ling-yan Li Hui Gu vesna Srot Peter van Aken Joachim Bill Materials Genome Institute School of Materials Science and EngineeringShanghai University99 Shangda RoadShanghai200444China Stuttgart Center for Electron Microscopy Max-Planck-lnstitute for Solid-State ResearchHeisen bergs trasse 370569StuttgartGermany Institute of Materials Science University of StuttgartHeisenbergstrasse 570569StuttgartGermany

Nucleation behavior of amorphous Si–B–C–N ceramics derived from boron-modified polyvinylsilazane procusors was systematically investigated by transmission electron microscopy(TEM) combined with spatially-resolved electron energy-loss spectroscopy(EELS) analysis. The ceramics were pyrolyzed at1000℃ followed by further annealing in N2, and SiC nano-crystallites start to emerge at 1200℃ and dominate at 1500℃. Observed by high-angle annular dark-field imaging, bright and dark clusters were revealed as universal nano-structured features in ceramic matrices before and after nucleation, and the growth of cluster size saturated before reaching 5 nm at 1400℃. EELS analysis demonstrated the gradual development of bonding structures successively into SiC, graphetic BNCxand Si3N4 phases, as well as a constant presence of unexpected oxygen in the matrices. Furthermore, EELS profiling revealed the bright SiC clusters and less bright Si3N4-like clusters at 1200–1400℃. Since the amorphous matrix has already phase separated into SiCN and carbon clusters, another phase separation of SiCN into SiC and Si3N4-like clusters might occur by annealing to accompany their nucleation and growth, albeit one crystallized and another remained in amorphous structure. Hinderance of the cluster growth and further crystallization was owing to the formation of BNCxlayers that developed between SiC and Si3N4-like clusters as well as from the excessive oxygen to form the stable SiO2.

关键词： Precursor derived ceramics Si–B–C–N Nucleation High-angle annular dark-field imaging Electron energy-loss spectroscopy

Does shifting to professional emergency department staffing affect the decision for chest radiography?

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World Journal of Emergency Medicine 2021年第2期12卷 87-92页

作者： Marin Pavlov Lucija Klobucar Iva Klobučar Kristinazgela vesna Degoricija Department of Cardiology Sestre Milosrdnice University Hospital CentreZagreb 10000Croatia Institute of Emergency Medicine Osijek-Baranja CountyOsijek 31000Croatia University of Zagreb School of Medicine Zagreb 10000Croatia Department of Medicine Sestre milosrdnice University Hospital CentreZagreb 10000Croatia

BACKGROUND: The study aims to determine whether shifting to professional emergency department(ED) teams leads to a higher rate of radiologic ***: We retrospectively analyzed a total of 2,000 patients presenting to the ED of a tertiary teaching hospital in two time periods: group 1(G1) comprised 1,000 consecutive patients enrolled from December 21, 2012 to January 5, 2013(all patients were examined by an internal medicine specialist);group 2(G2) comprised 1,000 consecutive patients enrolled from December 21, 2018 to January 3, 2019(all patients were examined by an emergency physician).RESULTS: The chest X-ray(CXR) was performed in 40.6% of all patients. There was no difference in the frequency of CXR(38.9% in G1 vs. 42.3% in G2, P=0.152). More CXRs were performed in G2 patients older than 65 years, in female patients older than 65 years, in patients presenting during the evening and night shifts or off-hours, in patients with a history of malignancy, in patients with gastrointestinal bleeding, and in patients with bradycardia, but fewer in patients presenting with arrhythmia. No difference in the rates of pathological CXR was found(47.3% in G1 vs. 52.2% in G2, P=0.186). Compared with G2, higher sensitivity and specificity were obtained for the binary logistic regression model predicting pathological findings in ***: Shifting to professional ED teams does not increase radiologic workup. By implementing deliberate usage of ultrasound, some self-governing procedures, case-oriented investigations, and center-specific recommendations, unnecessary radiologic workup can be avoided. Professional ED teams could lead to a higher standard of emergency care.

关键词： Chest radiography Emergency department Emergency physicians Healthcare organization

Immune defense of wild-caught Norway rats is characterized by increased levels of basal activity but reduced capability to respond to further immune stimulation

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Integrative Zoology 2018年第2期13卷 180-193页

作者： Ivana MIRKOV Aleksandra POPOV ALEKSANDROV vesna SUBOTA Dragan KATARANOVSKI Milena KATARANOVSKI Immunotoxicology Group Department of EcologyInstitute for Biological Research“Sinisa Stankovic”University of BelgradeBelgradeSerbia Institute for Medical Biochemistry Military Medical AcademyBelgradeSerbia Institute of Zoology Faculty of BiologyUniversity of BelgradeBelgradeSerbia Institute of Physiology and Biochemistry Faculty of BiologyUniversity of BelgradeBelgradeSerbia

Studies of wild animals’immunity often use comparison with laboratory-raised *** such an approach,various data were obtained concerning wild Norway rat’s *** or higher potential of immune system cells to respond to activation stimuli were shown,because of analysis of disparate parameters and/or small number of analyzed *** differences between laboratory and wild rats were shown too,owing to great response variability in wild *** hypothesized that wild rats will express more intense immune activity compared to their laboratory counterparts which live in a less demanding *** test this,we analyzed the circulating levels of inflammatory cytokine interleukin-6(IL-6),a mediator which has a central role in host immune *** addition,we examined the activity of the central immune organ,the spleen,including cell proliferation and production of pro-inflammatory cytokines interferon-γ(IFN-γ)and interleukin-17(IL-17),which are major effectors of cellular adaptive immune *** order to obtain reasonable insight into the immunity of wild Norway rats,analysis was conducted on a much larger number of individuals compared to other *** levels of plasma IL-6,higher spleen mass,cellularity and basal IFN-γproduction concomitantly with lower basal production of anti-inflammatory cytokine interleukin-10(IL-10)revealed more intense immune activity in the wild compared to laboratory ***,lower responsiveness of their spleen cells’proinflammatory cytokine production to concanavalin A(ConA)stimulation,along with preserved capacity of IL-10 response,might be perceived as an indication of wild rats’reduced capability to cope with incoming environmental stimuli,but also as a means to limit tissue damage.

关键词： circulating interleukin-6 levels spleen cell cytokine production spleen cell proliferation