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Journal of Materials Science & Technology 2015年第8期31卷 773-783页

作者： aleksandra Nastic Ali Merati Mariusz Bielawski Manon Bolduc Olaniyi Fakolujo Michel Nganbe Department of Mechanical Engineering University of Ottawa National Research Council Canada Defence R&D Canada(DRDC Valcartier)

Instrumented and Vickers indentation testing and microstructure analysis were used to investigate zirconia toughened alumina （ZTA） and silicon carbide （SIC）. Several equations were studied to relate the Vickers indentation hardness, Young＇s modulus and crack behavior to the fracture toughness. The frac- ture in SiC is unstable and occurs primarily by cleavage leading to a relatively low toughness of 3 MPa m1/2, which may be inappropriate for multi-hit capability. ZTA absorbs energy by plastic deformation, pore collapse, crack deviation and crack bridging and exhibits time dependent creep. With a relatively high toughness around 6.6 MPa m1/2, ZTA is promising for multi-hit capability. The higher accuracy of median equations in calculating the indentation fracture toughness and the relatively high c/a ratios above 2.5 suggest median type cracking for both SiC and ZTA. The Young＇s modulus of both ceramics was most accurately measured at lower indentation loads of about 0.5 kgf, while more accurate hardness and fracture toughness values were obtained at intermediate and at higher indentation loads beyond 5 kgf, respectively. A strong indentation size effect （ISE） was observed in both materials. The load independent hardness of SiC is 2563 HV, putting it far above the standard armor hardness requirement of 1500 HV that is barely met by ZTA.

关键词： Zirconia toughened alumina Silicon carbide Armor Vickers indentation fracture toughness Elastic modulus Vickers hardness

Giant pseudoaneurysm of the splenic artery within walled of pancreatic necrosis on the grounds of chronic pancreatitis

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Hepatobiliary & Pancreatic Diseases International 2021年第1期20卷 87-89页

作者： Milica Mitrovic Jovanovic Dusan Saponjski aleksandra Djuric Stefanovic aleksandra Jankovic Stefan Milosevic Katarina Stosic Djordje Knezevic Jelena Kovac Department of Abdominal Radiology Center for Radiology and MRIClinical Center of SerbiaBelgradeSerbia Faculty of Medicine University of BelgradeBelgradeSerbia Clinic for Digestive Surgery–First Surgical Clinic Clinical Center of SerbiaBelgradeSerbia

Chronic pancreatitis is a long-standing inflammation of the pancreas,characterized by progressive inflammatory and fibrotic changes,resulting in permanent structural damage of pancreatic parenchyma[1].Pancreatitis(chronic or acute)is the primary risk factor for pseudo-splenic artery aneurysms,along with pancreatic pseudocysts and *** the disease progresses,patients with chronic pancreatitis may develop complications due to exocrine and endocrine pancreatic functional loss,such as fat malabsorption with steatorrhea,glucose intolerance,and ultimately diabetes mellitus[1,2].Furthermore,severe pancreatic inflammation can cause weakening of vessel walls,with subsequent formation of arterial *** artery is the most commonly affected visceral artery[2,3].Liver cirrhosis,portal hypertension,liver transplantation,atherosclerosis,hypertension,pregnancy and multiparity are main risk factors for true splenic artery aneurysms[2].Rupture and intraperitoneal bleeding is the cause of death in 30%−50%of ***,prompt diagnosis and appropriate treatment are of great clinical importance[4,5].Herein,we present a case of a giant splenic artery pseudoaneurysm within a walled of necrosis involving pancreatic parenchyma,as a complication of long standing chronic pancreatitis.

关键词： pancreatitis aneurysm inflammation

Catalytic Kinetic Spectrophotometric Method for Determination of Phosphate Ion

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Chinese Journal of Chemistry 2007年第4期25卷 531-534页

作者： MITIC Snezana ZIVANOVIC Valentina OBRADOVIC Mirjana TOSIC Snezana PAVLOVIC aleksandra Faculty of Sciences and Mathematics Department of Chemistry University of Nig Visegradska 33 P.O. Box 224 18000 Nis Serbia

The kinetic method for the determination of phosphate microamounts was described. The developed method is based on catalytic effect of phosphate on sodium pyrogallol-5-sulphonate （PS） by dissolved oxygen. The reaction was followed spectrophotometrically by measuring the rate of change in the values of the absorbance of the oxidation product at 437 nm. The optimum reaction conditions are PS （0.44×10^-3 mol·L^-1） and HClO4 （3.6×10^-6 mol·L^-1） at 25 ℃. Following this procedure, phosphate can be determined with a linear calibration graph up to 0.23 μg·mL^-1. The interference effect of several species was also investigated and it was found that the most common cations and anions did not interfere with the determination. The developed procedure was successfully applied to the determination of phosphate in natural waters and soil.

关键词： kinetic spectrophotometric method sodium pyrogallol-5-sulphonate phosphate oxygen oxidation determination water soil

Biogeography and Evolutionary Factors Determine Genetic Differentiation of Pinus mugo(Turra) in the Tatra Mountains(Central Europe)

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Journal of Mountain Science 2015年第3期12卷 549-557页

作者： CELINSKI Konrad ZBRáNKOVá Veronika WOJNICKA-PóLTORAK aleksandra CHUDZINSKA Ewa Department of Genetics Adam Mickiewicz University in Poznań Department of Biology and Ecology University of Ostrava

Inter Simple Sequence Repeats(ISSR) markers were used to assess genetic diversity within and among populations of dwarf mountain pine(Pinus mugo Turra) growing in the Tatra National Park(UNESCO Biosphere Reserve) in Southern Poland(Central Europe). The analyzed population belongs to two different geobotanical sub-districts: the Western and High Tatras. The level of genetic diversity assessed in this study for P. mugo is generally comparable to that reported for the other pine species in the Pinaceae family assessed by ISSR markers, especially with respect to Nei's genetic diversity and the percentage of polymorphic bands. Bayesian analysis clustered the analyzed populations into two groups, corresponding to their geobotanical locations in the Tatras. Significant divergence between the two genetical clusters was supported by the results of Analysis of Molecular Variance(AMOVA). According to the Mantel test, there was no correlation between the genetic distance and the geographical distance. The present study confirms the existence of two genetically distinct clusters of P. mugo populations in the Tatra Mountains. The observed high population-genetic differentiation of *** in the Tatras could be attributed to several genetic, environmental and historical factors occurring in this mountain area.

关键词：遗传分化生物地理学高塔进化因素中欧山松联合国教科文组织遗传多样性

Routine pediatric vaccinations during the COVID-19 pandemic:A review of the global impact

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World Journal of Virology 2023年第5期12卷 256-261页

作者： Jennifer Locke aleksandra Marinkovic Kareem Hamdy Vyshnavy Balendra Adekunle Sanyaolu Basic Medical Science Saint James School of MedicineThe Quarter 26400000Anguilla Osteopathic Medicine D’Youville University320 Porter AveBuffaloNY 14201United States

The coronavirus disease 2019(COVID-19)pandemic has put standard,routine childhood vaccinations at risk *** disruption in vaccine coverage has resulted in a negative impact on the health of children,with some races,ethnicities,age groups,areas of settlement,and parts of the world affected more than *** literature review studied and examined the impact of COVID-19 on infant,child,and adolescent ***,the analysis showed a decline,delays,or interruptions in the coverage of vaccines during the pandemic and a decline in some countries'pre-pandemic and post-pandemic *** attempts and efforts should be made for these delayed and missed vaccinations,as failure to do so could put children's health at ***,priority should be directed at instituting catch-up programs to support vaccine uptake and decrease the probability of acquiring vaccine-preventable diseases.

关键词： Pediatric Vaccination Coronavirus disease 2019 Humans Pandemics

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

Persistent dysexecutive syndrome after pneumococcal meningitis complicated by recurrent ischemic strokes:A case report

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World Journal of Clinical Cases 2023年第22期11卷 5344-5350页

作者： Laura Abbruzzese Giulia Martinelli Giulia Salti Benedetta Basagni Alessio Damora Cristiano Scarselli Giulia Peppoloni aleksandra Podgorska Giuliana Rosso Marco Bacci Alba Rosa Alfano MAURO MANCUSO CRT Tuscany Rehabilitation ClinicMontevarchiArezzo 52025Italy Physical and Rehabilitative Medicine Unit NHS ASL-Tuscany South EstGrosseto 58100Italy Department of Internal Medicine and Medical Specialties UOC GeriatricsSapienza University of RomeRome 00185Italy

Meningitis is a possible complication of pneumococcal infection concerning acute otitis media and *** might compromise cognitive function,both for the infection itself and the vascular events that sometimes follow the acute *** SUMMARY Here we describe the case of a 32-year-old female patient admitted to the emergency room due to extensive pneumococcal meningitis as a consequence of sinus *** presented with extensive laminar ischemic damage in the acute phase,resulting in severe cognitive and behavioural *** years of follow-up,through neuropsychological assessments and neuroradiological investigations,demonstrated the presence of subsequent vascular events,3 months and 2 years after *** The case is discussed in light of scientific knowledge of the long-term outcomes of this pathology in order to potentially improve diagnosis and promote better outcomes.

关键词： Pneumococcal meningitis Stroke,Cognitive and behavioural functioning Long-term outcome Case report

Liver disease and COVID-19:The link with oxidative stress,antioxidants and nutrition

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World Journal of Gastroenterology 2021年第34期27卷 5682-5699页

作者： Danijela Ristic-Medic Snjezana Petrovic aleksandra Arsic Vesna Vucic Group for Nutritional Biochemistry and Dietology Centre of Research Excellence in Nutrition and MetabolismNational Institute for Medical ResearchUniversity of BelgradeBelgrade 11129Serbia

Varying degrees of liver injuries have been reported in patients infected with the severe acute respiratory syndrome-coronavirus-2(SARS-CoV-2).In general,oxidative stress is actively involved in initiation and progression of liver *** liver metabolizes various compounds that produce free *** the oxidative/antioxidative balance is important in coronavirus disease 2019(COVID-19)*** vitamins,essential trace elements and food compounds,such as polyphenols,appear to be promising agents,with effects in oxidative *** of these nutrients suppresses immune function and increases susceptibility to *** micronutrient intake is necessary to support anti-inflammatory and antioxidative effects but for immune function may be higher than current recommended dietary *** supplements(β-carotene,vitamin A,vitamin C,vitamin E,and selenium)could have a potential role in patients with liver *** evidence suggests that supplementing the diet with a combination of micronutrients may help to optimize immune function and reduce the risk of *** trials based on the associations of diet and SARS-CoV-2 infection are ***,it is not possible to definitively determine the dose,route of administration and best timing to intervene with antioxidants in COVID-19 patients because clinical trials are still *** then,hopefully,this review will enable clinicians to understand the impact of micronutrient dietary intake and liver status assessment in COVID-19 patients.

关键词： SARS-CoV-2 COVID-19 Liver injury Antioxidants Nutrients Treatment

Leptin/leptin receptor system in the regulation of reproductive functions and stress response in the European beaver

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Current Zoology 2019年第2期65卷 197-203页

作者： Katarzyna CHOJNOWSKA Joanna CZERWINSKA Tadeusz KAMINSKI Barbara KAMINSKA aleksandra KURZYNSKA Iwona BOGACKA Department of Animal Anatomy and Physiology Faculty of Biology and Biotechnology University of Warmia and Mazury in Olsztyn Oczapowskiego Street 1A Olsztyn 10-719 Poland

The European beaver (Castor fiber L.) is the largest free-living rode nt in Eurasia. The prese nt work aimed to determi ne sex- and seas on-related cha nges in leptin receptor (Ob-R) expression in the hypothalamic-pituitary-gonadal/adrenal axes and uterus of beavers during breeding-(April), postbreeding-(July), and pre-breeding-(November) periods. The expression of Ob-R gene and protein was found in all analyzed tissues. The expression of Ob-R mRNA remained constant in the hypothalamus of both sexes during the analyzed stages. Sex- and season-related changes were found in the pituitary gland;the greatest level was observed in July in both sexes. The same expression pattern was noted in the testis, whereas in the ovary a lack of seasonal changes was found. In uterine tissues, the greatest expression occurred in November. The impact of season was also demonstrated in the adrenal cortex. In females, a higher Ob-R transcript level was noted in April, while in males, an increased mRNA abundanee was noted in November than July. Our study suggests that in the beaver, leptin acting via the Ob-R can be an important endocrine factor engaged in the regulation of reproductive functions and stress response.

关键词： leptin receptor (Ob-R) beaver seasonal breeding hypothalamic-pituitary-gonadal axis (HPG) hypothalamic-pituitary-adrenal axis (HPA)

Theoretical Study of Adsorption Behavior of Vemurafenib Drug over BNNT(5,5-9) as a Factor of Drug Delivery: a DFT Study

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Chinese Journal of Structural Chemistry 2020年第8期39卷 1422-1436,1358页

作者： MASOOME Sheikhi SIYAMAK Shahab HORA Alhosseini Almodarresiyeh MEHRNOOSH Khaleghian RAKESH Kumar aleksandra Strogova Young Researchers and Elite Club Gorgan BranchIslamic Azad UniversityGorganIran Belarusian State University ISEI BSUMinskRepublic of Belarus Institute of Physical Organic Chemistry National Academy of Sciences of Belarus13 Surganov Str.Minsk 220072Republic of Belarus Institute of Chemistry of New Materials National Academy of Sciences of Belarus36 Skarina Str.Minsk 220141Republic of Belarus Department of Materials and Metallurgy Engineering Meybod UniversityMeybodIran Department of Chemistry Islamshahr BranchIslamic Azad UniversityIslamshahrIran Department of Chemistry MCM DAV College Kangra Himachal Pradesh 176001(India)

In this research,a density functional theory(DFT)calculation was performed for investigation adsorption behavior of the anticancer drug Vemurafenib on BNNT(5,5-9)by using the M06-2X/6-31 G*level of theory in the solvent *** electronic spectra of the Vemurafenib drug,BNNT(5,5-9)and complex BNNT(5,5-9)/Vemurafenib in solvent water were calculated by Time Dependent Density Functional Theory(TD-DFT)for the study of adsorption *** non-bonded interaction effects of the Vemurafenib drug with BNNT(5,5-9)on the electronic properties,natural charges and chemical shift tensors have been also *** results display the change in title parameters after process *** to the natural bond orbital(NBO)results,the molecule Vemurafenib and BNNT(5,5-9)play as both electron donor and acceptor at the complex BNNT(5,5-9)/*** the other hand,the charge transfer occurs between the bonding,antibonding or nonbonding orbitals in two molecules drug and *** a consequence,BNNT(5,5-9)can be considered as a drug delivery system for the transportation of Vemurafenib as anticancer drug within the biological systems.

关键词： vemurafenib BNNT(5,5-9) DFT charge transfer NBO