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When a TeV-scale leptoquark has a sizeable Yukawa coupling, its dominant production mechanism at hadron colliders is the partonic-level lepton-quark fusion. Even though the parton distribution functions for leptons inside the proton are minuscule, they get compensated by the resonant enhancement. We present the first computation of higher order radiative corrections to the resonant leptoquark production cross section at the Large Hadron Collider (LHC). Next-to-leading (NLO) QCD and QED corrections are similar in size but come with the opposite sign. We compute NLO K-factors for a wide range of scalar leptoquark masses, as well as, all possible combinations of quark and lepton flavors and leptoquark charges. Theoretical uncertainties due to the renormalisation and factorisation scale variations and the limited knowledge of parton distribution functions are quantified. We finally discuss how to disentangle the flavor structure of leptoquark interactions by exploiting the interplay between different production channels.

Emina Todorovac, Irma Durmišević, Selma Cajo, A. Haverić, A. Mesic

Abstract The aim of this study was to determine the cytogenotoxic effects of methylparaben, ethylparaben and butylparaben using battery of tests in plant cells (Allium cepa assay) and human lymphocytes (chromosome aberration test and alkaline comet assay). Our results for A. cepa assay showed that none of the tested parabens showed an inducing effect on root growth. Mitotic index values decreased with increasing parabens concentration. Ethylparaben (0.10 mg/L) induced a higher number of vagrants and multipolarity, as well as the number of sticky chromosomes (0.50 mg/L), while butylparaben (0.25 and 0.50 mg/L) increased the frequency of sticky chromosomes. Higher frequency of apoptosis and necrosis was observed for ethylparaben (0.50 mg/L) and methylparaben (0.10 and 0.50 mg/L). As for chromosome aberrations test in human lymphocytes, the mitotic index was reduced with an increase in the concentration of all three tested parabens. Differences between methylparaben (0.25 mg/L), ethylparaben (0.10 mg/L) and butylparaben (0.25 mg/L) and controls for acentric fragments, chromatid breaks and polyploidy were observed. Increased frequency of apoptosis was induced by methylparaben and ethylparaben at concentrations of 0.25 and 0.50 mg/L. Alkaline comet assay demonstrated that 0.25 and 0.50 mg/L of ethylparaben and butylparaben have genotoxic potential by increasing the tail intensity against controls. These results suggest that methyl-, ethyl- and butylparaben possess certain geno/cytotoxic potential.

U. Glamočlija, S. Špirtović-Halilović, M. Salihović, I. Turel, Jakob Kljun, E. Veljović, S. Zukić, D. Završnik

Using X-ray single crystal diffraction, the crystal structures of biologically active benzoxazole derivatives were determined. DFT calculation was performed with standard 6-31G*(d), 6-31G** and 6-31+G* basis set to analyze the molecular geometry and compare with experimentally obtained X-ray crystal data of compounds. The calculated HOMO-LUMO energy gap in compound 2 (2-(2-hydroxynaphtalen-1-yl)-4-methyl-7-isopropyl-1,3-benzoxazol-5-ol) is 3.80 eV and this small gap value indicates that compound 2 is chemically more reactive compared to compounds 1 (4-methyl-2-phenyl-7-isopropyl-1,3-benzoxazol-5-ol) and 3 (2-(4-chlorophenyl)-4-methyl-7-isopropyl-1,3-benzoxazol-5-ol). The crystal structures are stabilized by both intra- and intermolecular hydrogen bonds in which an intermolecular O-H⋅⋅⋅N hydrogen bond generates N3 and O7 chain motif in compounds 1, 2, and 3, respectively. The calculated bond lengths and bond angles of all three compounds are remarkably close to the experimental values obtained by X-ray single crystal diffraction.

M. Silva, Rosineide Magalhães de Sousa

O artigo analisa textos de estudantes do setimo ano, do Ensino Fundamental de uma escola publica do campo, de Barreiras – BA. Nessa analise, consideramos o contexto social, economico e cultural a que pertencem esses estudantes. Metodologicamente, trabalhamos etnografia de sala de aula, realizando: observacao, descricao e analise, e participacao colaborativa, com a aplicacao de sequencia didatica, e o uso do texto biografico, subsidiando a producao do texto autobiografico. A luz da teoria dos letramentos multiplos e da leitura sociolinguistica, foi possivel reconhecer a necessidade da observacao do lugar de pertenca do estudante no/do campo e suas distintas praticas de conhecimento de leitura e de escrita, bem como a importância da valorizacao dessa cultura no contexto escolar. Encontramos nos textos escritos, evidentes demarcacoes dos fatores socioculturais de seu autor, com multiplas expressoes e marcas linguisticas que identificam o lugar de pertencimento que, em certos casos, nao sao compreendidas em sala de aula.

L. Alic, J. Griffin, Aydin Eresen, J. Kornegay, J. Ji

There is a great demand for accurate non‐invasive measures to better define the natural history of disease progression or treatment outcome in Duchenne muscular dystrophy (DMD) and to facilitate the inclusion of a large range of participants in DMD clinical trials. This review aims to investigate which MRI sequences and analysis methods have been used and to identify future needs. Medline, Embase, Scopus, Web of Science, Inspec, and Compendex databases were searched up to 2 November 2019, using keywords “magnetic resonance imaging” and “Duchenne muscular dystrophy.” The review showed the trend of using T1w and T2w MRI images for semi‐qualitative inspection of structural alterations of DMD muscle using a diversity of grading scales, with increasing use of T2map, Dixon, and MR spectroscopy (MRS). High‐field (>3T) MRI dominated the studies with animal models. The quantitative MRI techniques have allowed a more precise estimation of local or generalized disease severity. Longitudinal studies assessing the effect of an intervention have also become more prominent, in both clinical and animal model subjects. Quality assessment of the included longitudinal studies was performed using the Newcastle‐Ottawa Quality Assessment Scale adapted to comprise bias in selection, comparability, exposure, and outcome. Additional large clinical trials are needed to consolidate research using MRI as a biomarker in DMD and to validate findings against established gold standards. This future work should use a multiparametric and quantitative MRI acquisition protocol, assess the repeatability of measurements, and correlate findings to histologic parameters.

D. Abueidda, Q. Lu, S. Koric

Deep learning (DL) and the collocation method are merged and used to solve partial differential equations (PDEs) describing structures' deformation. We have considered different types of materials: linear elasticity, hyperelasticity (neo‐Hookean) with large deformation, and von Mises plasticity with isotropic and kinematic hardening. The performance of this deep collocation method (DCM) depends on the architecture of the neural network and the corresponding hyperparameters. The presented DCM is meshfree and avoids any spatial discretization, which is usually needed for the finite element method (FEM). We show that the DCM can capture the response qualitatively and quantitatively, without the need for any data generation using other numerical methods such as the FEM. Data generation usually is the main bottleneck in most data‐driven models. The DL model is trained to learn the model's parameters yielding accurate approximate solutions. Once the model is properly trained, solutions can be obtained almost instantly at any point in the domain, given its spatial coordinates. Therefore, the DCM is potentially a promising standalone technique to solve PDEs involved in the deformation of materials and structural systems as well as other physical phenomena.

L. Pojskić, E. Štimjanin, H. Selimović, M. Sut, A. Brkovic, M. Sammak, H. Torlak, M. Ejubović et al.

H. Selimović, L. Pojskić, E. Štimjanin, M. Sut, A. Brkovic, M. Sammak, H. Torlak, M. Ejubović et al.

Abstract The most commonly farmed fish species in Bosnia and Herzegovina’s aquaculture are from the family Salmonidae, including brook trout Salvelinus fontinalis which is reared both for consumption and stocking purposes. A number of farmers complained about the elevated frequency of anatomical deformities in the smolts and fingerlings of brook trout, decreasing their fitness rate and causing significant financial loss. Since it has been shown that occurrence of deformities is correlated with the low genetic diversity and high inbreeding, this study aimed to assess intra- and interpopulation diversity of Salvelinus fontinalis from different freshwater fish farms in Bosnia and Herzegovina by observing variation in mitochondrial and nuclear genome. Total of 109 samples of brook trout from three hatcheries located at the Neretva River were analyzed for the mitochondrial control region and seven nuclear microsatellite loci. Both PCR-RFLP and sequencing revealed only one haplotype of the control region in all investigated trout. Overall, a low number of genotypes was evident across all the observed loci. Values of genetic diversity and polymorphic information content followed the increase in the number of alleles per locus. In general, values of inbreeding coefficient were generally very high, while the genetic diversity and observed heterozygosity had low rates. The results of our study are congruent with the findings of previous studies in which developmental deformities were concomitant with the low genetic diversity and inbreeding depression. It is, therefore, strongly advised to regularly supplement the broodstock with new, unrelated individuals, as it is of vital importance for sustaining a satisfying level of genetic diversity and preventing inbreeding depression. Additionally, maintaining good management practices regarding the fluctuation of water temperature, exposure to pollution, nutrition, etc., will further contribute to the prevention of this detrimental condition.

Objectives Demarcated opacities (DO) on teeth affected by Molar Incisor Hypomineralisation (MIH) were observed to investigate if parameters of DO existence and the number of teeth affected could be used to predict the progression of disease. Material and methods In 2009, the MIH prevalence was 11.5% (n=51) among 446 subjects in Sarajevo, aged from 6 to 9 years. In subjects with MIH who gave consent for further participation (n=25), the teeth with DO were observed after a 12-month period. Results our sample included 29 permanent incisors and 14 first permanent molars with DO. The number of teeth with light opacities was significantly higher than the number of teeth with dark opacities. Opacities were more numerous on surfaces which were not exposed to masticatory pressure. The size of tooth surface affected by DO occurrence ranged from 1.33% to 56.56%. The number of affected teeth ranged from two to six. A strong positive correlation between MIH progression and dark colored opacities located on the occlusal/incisal surface of teeth was noted. Larger part of tooth surface was affected by hypomineralisation in the case of dark-colored opacities. The DO presence on incisors was more likely to be located on vestibular surfaces and on the first permanent molars on their occlusal surfaces. Conclusions The color of DO occurrence was the best predictor for MIH progression both independently and in combination with the number of affected teeth. Location of DO occurrence was a good independent predictor for MIH progression. It is important to collect information about color and location of DO presence.

Amela Katica-Mulalić, E. Suljic, E. Begić, Azra Mukanovic-Alihodzic, S. Štraus, Amila Feto, Z. Dedovic, R. Gojak

Introduction: A promising strategy that can lead to longer brain cell survival after an acute stroke is therapeutic hypothermia. It represents a controlled decrease in body temperature for therapeutic reasons. It is increasingly represented as a therapeutic option and is one of the most challenging treatments that improves neurological recovery and treatment outcome in patients with acute stroke. Aim: To examine the effect of therapeutic hypothermia on liver enzymes in patients with diagnosis of stroke. Methods: A total of 101 patients diagnosed with acute stroke were treated. The first group (n=40) were treated with conventional treatment and therapeutic hypothermia, while the second group (n=61) only with conventional treatment. Cooling of the body to a target body temperature of 34°C to 35°C was performed for up to 24 hours. Outcome (survival or death) of treatment was monitored, degree of disability was determined by National Institutes of Health Stroke Scale (NIHSS) and assessment of consciousness using the Glasgow Coma Scale (GCS). Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) values were taken at admission, after 24 hours, and were monitored upon discharge. Results: There was a significant difference in AST values at admission relative to disease outcome (p = 0.002), as well as for ALT (p = 0.008). In patients treated with therapeutic hypothermia, mean AST values decreased after 24 hours (32.50 to 31.00 IU/mL) as well as ALT values (27.50 to 26.50 IU/mL), without statistical significance. In the group of subjects who survived with sequela, AST values correlated with GCS (rho = -0.489; p = 0.002) and NIHSS (rho = 0.492; p = 0.003), ALT values correlated with GCS (rho = -0.356; p = 0.03) but not with NIHSS. Conclusion: AST and ALT values at admission correlate with the severity of the clinical picture. Therapeutic hypothermia is hepatoprotective and lowers AST and ALT values.

S. Grebović, Mirza Batalovic, A. Balota, N. Oprašić

Abstract Line surge arresters are mainly used for transmission line lightning performance improvement. Calculation of energy stresses of lines surge arrester is of extreme importance for the selection of the arrester class. Energy stresses of transmission line surge arresters due to multicomponent lightning flashes are analysed in this paper. To obtain lightning data two approaches were used: direct measurements using instrumented towers and lightning location systems. Both lightning monitoring systems are described. Data obtained from lightning monitoring systems are compared and used in simulations. Detailed modelling procedure for a transient analysis of the transmission lines is also described. Multicomponent lightning flash and 110 kV transmission line were modelled using Electromagnetic Transient Program -Restructured Version (EMTP – RV). The arrester current shapes and arrester energy duties are presented in order to clearly show influence of lightning current parameters to arrester energy duty.

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