Lead contamination in fishes of the Kor River

Lead concentration in muscle, liver, kidney, brain and gonad tissues of two cyprinid fishes, Cyprinus carpio and Copoeta spp., from three sections of the upper, middle and lower parts of the Kor River was evaluated in 2006. Totally 225 specimens were caught for this purpose (75 specimens from each zone). Tissue samples were digested in acid and their lead concentrations were assayed by ICP method. Statistical analysis of data showed significantly (p0.05) were seen between sexes and species. The same pattern of contamination was also observed in water and sediment samples from three sampling zones. The maximum amount of lead measured in this study (1.85mg/kg), was, however, less than the maximum allowance in fish tissues by European Unions

Antiangiogenic activity of xanthomicrol and calycopterin, two polymethoxylated hydroxyflavones in both in vitro and ex vivo models

Our previous studies had shown xanthomicrol and calycopterin, two plant-derived flavonoids, to have selective antiproliferative activity against some malignant cell lines. The present study is focused on the investigation of antiangiogenic potential of these two flavonoids, using in vitro and ex vivo models. Xanthomicrol and calycopterin were found to have potent inhibitory effects on microvessel outgrowth in the rat aortic ring assay. Xanthomicrol was able to completely block microvessel sprouting at 10 μg/mL, and calycopterin suppressed microvessel outgrowth by 89 at 5 μg/mL. Suramin and thalidomide, used at 20 μg/mL as positive controls, inhibited microvessel formation by 23 and 64, respectively. The flavones also inhibited endothelial cell tube formation and human umbilical vein endothelial cell proliferation at 0.5, 5, and 10 μg/mL. In order to delineate the underlying mechanisms of antiangiogenic activity of these flavones, we investigated the influences of xanthomicrol and calycopterin on expression of vascular endothelial growth factor (VEGF) and basic-fibroblast growth factor (b-FGF) in endothelial cells. These flavones were able to inhibit VEGF expression at 0.5, 5, and 10 μg/mL, but they had little or no effect on b-FGF expression. These findings suggest that xanthomicrol and calycopterin possess potent antiangiogenic activities, which may be due to their inhibitory influences on VEGF expression. Copyright © 2014 John Wiley & Sons, Ltd

Wharton's jelly derived-mesenchymal stem cells: Isolation and characterization

Wharton`s jelly-derived mesenchymal stem cells (WJ-MSCs), have a high proliferation valency and they do not produce teratogen or carcinogen after subsequent transplantation. They are known as regenerative medicine. Thus more research is needed on the isolation and characterization of mesenchymal stem cells. In this experimental study, we obtained Wharton's jelly tissues from mothers during normal vaginal delivery, after obtaining their informed consent. Mesenchymal stem cells were isolated from cultured Wharton`s jelly, cultured, and were then examined for their proliferation, immunophenotypes, and differentiation capacities. The immunophenotypes of WJ-MSCs were analyzed by flow cytometry. Differentiation was performed resulting in osteogenic, chondrogenic and adipogenic cells. WJ-MSCs formed a homogenous monolayer of adherent spindle-shaped cells. Our results showed the high capacity of the proliferation of WJ-MSCs. Immunophenotyping further confirmed the purity of the isolated cells; their surface antigen expression showed the phenotypical properties like those of WJ-MSCs. The expanded cells were positive for CD 90, CD105, and CD44; they were negative for CD34 and HLA-DR surface markers. The cells had the adipocytic, osteocytic and chondrogenic differentiation capacity. The isolation and characterization of WJ-MSCs with high purity had been conducted, and the results were obtained in a short span. The present study has revealed the feasibility of the culture medium with high glucose and 15 FBS in isolation and proliferation of WJ-MSCs. When Wharton`s jelly pieces were put in the dry bottom of the flask, very effective separation of the MSCs was achieved. © 2018 Tehran University of Medical Sciences. All rights reserved

Wharton's jelly derived-mesenchymal stem cells: Isolation and characterization

Wharton`s jelly-derived mesenchymal stem cells (WJ-MSCs), have a high proliferation valency and they do not produce teratogen or carcinogen after subsequent transplantation. They are known as regenerative medicine. Thus more research is needed on the isolation and characterization of mesenchymal stem cells. In this experimental study, we obtained Wharton's jelly tissues from mothers during normal vaginal delivery, after obtaining their informed consent. Mesenchymal stem cells were isolated from cultured Wharton`s jelly, cultured, and were then examined for their proliferation, immunophenotypes, and differentiation capacities. The immunophenotypes of WJ-MSCs were analyzed by flow cytometry. Differentiation was performed resulting in osteogenic, chondrogenic and adipogenic cells. WJ-MSCs formed a homogenous monolayer of adherent spindle-shaped cells. Our results showed the high capacity of the proliferation of WJ-MSCs. Immunophenotyping further confirmed the purity of the isolated cells; their surface antigen expression showed the phenotypical properties like those of WJ-MSCs. The expanded cells were positive for CD 90, CD105, and CD44; they were negative for CD34 and HLA-DR surface markers. The cells had the adipocytic, osteocytic and chondrogenic differentiation capacity. The isolation and characterization of WJ-MSCs with high purity had been conducted, and the results were obtained in a short span. The present study has revealed the feasibility of the culture medium with high glucose and 15 FBS in isolation and proliferation of WJ-MSCs. When Wharton`s jelly pieces were put in the dry bottom of the flask, very effective separation of the MSCs was achieved. © 2018 Tehran University of Medical Sciences. All rights reserved

QCD ghost f(T)-gravity model

Within the framework of modified teleparallel gravity, we reconstruct a f(T) model corresponding to the QCD ghost dark energy scenario. For a spatially flat FRW universe containing only the pressureless matter, we obtain the time evolution of the torsion scalar T (or the Hubble parameter). Then, we calculate the effective torsion equation of state parameter of the QCD ghost f(T)-gravity model as well as the deceleration parameter of the universe. Furthermore, we fit the model parameters by using the latest observational data including SNeIa, CMB and BAO data. We also check the viability of our model using a cosmographic analysis approach. Moreover, we investigate the validity of the generalized second law (GSL) of gravitational thermodynamics for our model. Finally, we point out the growth rate of matter density perturbation. We conclude that in QCD ghost f(T)-gravity model, the universe begins a matter dominated phase and approaches a de Sitter regime at late times, as expected. Also this model is consistent with current data, passes the cosmographic test, satisfies the GSL and fits the data of the growth factor well as the LCDM model.Comment: 19 pages, 9 figures, 2 tables. arXiv admin note: substantial text overlap with arXiv:1111.726

Analysis of microstructure effects on edge crack of thin strip during cold rolling

Edge cracks in cold rolling of the thin strip affect the strip quality and productivity significantly. In this study, an experimental and mechanical investigation on microstructures has been carried out to study the edge crack formation during cold rolling of the thin strip. The effects of the feed material microstructures on the edge crack evolution were studied employing optical microscopy and scanning electron microscopy (SEM). Experimental observation indicates that fine grain occurs in hot-rolled microstructure and coarse grain is produced in ferritic rolled microstructure. Different grain sizes affect significantly the formation mechanics of the microcrack, crack initiation, and orientation of crack extension. The grain size and grain boundaries effects on crack retardation are discussed also during edge crack initiation. During the crack growth in coarse grain, most edge crack tips will blunt, which improves the crack toughness by causing less stress concentration. Overall, the fine microstructure shows a good crack initiation resistance, whereas the coarse microstructure has a better resistance to crack propagation. This research provides additional understanding of the mechanism of microstructure influence on edge crack evolution of cold strip rolling, which could be helpful for developing defect-free thin strip

Measurement of the azimuthal anisotropy of Y(1S) and Y(2S) mesons in PbPb collisions at √S^{S}NN = 5.02 TeV

The second-order Fourier coefficients (υ$_{2}$) characterizing the azimuthal distributions of Υ(1S) and Υ(2S) mesons produced in PbPb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV are studied. The Υmesons are reconstructed in their dimuon decay channel, as measured by the CMS detector. The collected data set corresponds to an integrated luminosity of 1.7 nb$^{-1}$. The scalar product method is used to extract the υ$_{2}$ coefficients of the azimuthal distributions. Results are reported for the rapidity range |y| < 2.4, in the transverse momentum interval 0 < p$_{T}$ < 50 GeV/c, and in three centrality ranges of 10–30%, 30–50% and 50–90%. In contrast to the J/ψ mesons, the measured υ$_{2}$ values for the Υ mesons are found to be consistent with zero

Measurement of prompt D0^{0} and D‾\overline{D}0^{0} meson azimuthal anisotropy and search for strong electric fields in PbPb collisions at root SNN\sqrt{S_{NN}} = 5.02 TeV

The strong Coulomb field created in ultrarelativistic heavy ion collisions is expected to produce a rapiditydependent difference (Av2) in the second Fourier coefficient of the azimuthal distribution (elliptic flow, v2) between D0 (uc) and D0 (uc) mesons. Motivated by the search for evidence of this field, the CMS detector at the LHC is used to perform the first measurement of Av2. The rapidity-averaged value is found to be (Av2) = 0.001 ? 0.001 (stat)? 0.003 (syst) in PbPb collisions at ?sNN = 5.02 TeV. In addition, the influence of the collision geometry is explored by measuring the D0 and D0mesons v2 and triangular flow coefficient (v3) as functions of rapidity, transverse momentum (pT), and event centrality (a measure of the overlap of the two Pb nuclei). A clear centrality dependence of prompt D0 meson v2 values is observed, while the v3 is largely independent of centrality. These trends are consistent with expectations of flow driven by the initial-state geometry. ? 2021 The Author. Published by Elsevier B.V. This is an open access article under the CC BY licens

Performance of the CMS Level-1 trigger in proton-proton collisions at √s = 13 TeV

At the start of Run 2 in 2015, the LHC delivered proton-proton collisions at a center-of-mass energy of 13\TeV. During Run 2 (years 2015–2018) the LHC eventually reached a luminosity of 2.1× 10$^{34}$ cm$^{-2}$s$^{-1}$, almost three times that reached during Run 1 (2009–2013) and a factor of two larger than the LHC design value, leading to events with up to a mean of about 50 simultaneous inelastic proton-proton collisions per bunch crossing (pileup). The CMS Level-1 trigger was upgraded prior to 2016 to improve the selection of physics events in the challenging conditions posed by the second run of the LHC. This paper describes the performance of the CMS Level-1 trigger upgrade during the data taking period of 2016–2018. The upgraded trigger implements pattern recognition and boosted decision tree regression techniques for muon reconstruction, includes pileup subtraction for jets and energy sums, and incorporates pileup-dependent isolation requirements for electrons and tau leptons. In addition, the new trigger calculates high-level quantities such as the invariant mass of pairs of reconstructed particles. The upgrade reduces the trigger rate from background processes and improves the trigger efficiency for a wide variety of physics signals