158 research outputs found
S 4
Numerical solution of the transport equation for monoenergetic neutrons scattered isotropically through the medium of a finite homogeneous slab is studied for the determination of the eigenvalues. After obtaining the discrete ordinates form of the transport equation, separated homogeneous and particular solutions are formed and then the eigenvalues are calculated using the Gauss-Legendre quadrature set. Then, the calculated eigenvalues for various values of the c0, the mean number of secondary neutrons per collision, are given in the tables
Podwyższony poziom greliny w stanie przedrzucawkowym: czy grelina jest przyjacielem czy wrogiem?
Objectives: To investigate maternal serum ghrelin levels in pregnancies complicated by preeclampsia and to explore the relationship between ghrelin level and disease severity.
Materials and methods: This case-control study included 40 healthy pregnant women, 42 women with mild preeclampsia, and 40 women with severe preeclampsia. The groups were matched in terms of maternal and gestational age and body mass index. Serum ghrelin levels were measured via enzyme immunoassay.
Results: Serum ghrelin levels were significantly higher in women with mild and severe preeclampsia than in healthy controls (p < 0.001). Although serum ghrelin levels were somewhat higher in the severe compared to the mild preeclampsia group, the difference was not statistically significant (p > 0.05). In the control group, no significant correlation was observed between ghrelin level and any other parameter, but in the preeclampsia group, serum ghrelin levels were negatively correlated with uterine artery Doppler index values and both systolic and diastolic blood pressure (all p-values < 0.05). Multivariate stepwise linear regression analysis revealed that systolic blood pressure (β = 0.493, p = 0.023) was independently associated with serum ghrelin level.
Conclusion: Elevated blood ghrelin levels were correlated with disease severity in pregnancies complicated by preeclampsia.Cel pracy: Ocena poziomu greliny w surowicy kobiet w ciąży powikłanej stanem przedrzucawkowym i określenie związku między poziomem greliny a ciężkością choroby.
Materiał i metoda: Do badania włączono 40 zdrowych kobiet w ciąży, 42 z łagodnym stanem przedrzucawkowym i 40 z ciężkim stanem przedrzucawkowym. Grupy były dobrane pod względem wieku ciążowego, wieku matek i wskaźnika masy ciała. Poziom greliny w surowicy był mierzony metodą immunoenzymatyczną.
Wyniki: Poziom greliny w surowicy był istotnie wyższy u kobiet z łagodnym i ciężkim stanem przedrzucawkowym niż w grupie kontrolnej (p < 0,001). Chociaż poziom greliny w surowicy był wyższy w grupie z ciężkim stanem przedrzucawkowym niż w grupie z łagodnym stanem przedrzucawkowym, to ta różnica nie była istotna statystycznie (p > 0,05). W grupie kontrolnej nie obserwowano żadnych istotnych związków pomiędzy poziomem greliny a jakimkolwiek innym parametrem, ale w grupie ze stanem przedrzucawkowym poziom greliny w surowicy był ujemnie skorelowany z indeksami przepływów Dopplera w tętnicy macicznej oraz ciśnieniem krwi skurczowym i rozkurczowym (all p-values < 0,05). Wieloczynnikowa analiza regresji liniowej wykazała, że skurczowe ciśnienie krwi było niezależnym czynnikiem związanym z poziomem greliny w surowicy (β = 0,493, p = 0,023).
Wnioski: Podwyższony poziom greliny we krwi był związany z ciężkością choroby w ciążach powikłanych stanem przedrzucawkowym
New dinuclear cyanido complexes with amine alcohol ligand: synthesis, characterization and biotechnological application potential
In this study, the cyanido complexes given by the formula [Ni(Abut)Ni(CN)4]·8H2O (C1), [Cu(Abut)2Ni(CN)4]·7H2O (C2), [Zn(Abut)Ni(CN)4]·8H2O (C3) and [Cd(Abut)Ni(CN)4]·7H2O (C4) were obtained by microwave synthesis method. The powder forms of the complexes were characterized by elemental, FT-IR spectroscopy, and thermal analysis. And also antibacterial, antibiofilm and anticancer activities were investigated. The splitting stretching bands of cyanido groups in the FT-IR spectra of C1-C4 indicated the assets of terminal and end cyanido groups. The antibacterial activities of C1-C4 were tested with nine Gram negative and six Gram positive bacteria. The most efficient antibacterial activity of complexes was observed at 1000 µg/ml-1 concentration. Anticancer activity was tested using HeLa cell line and MTT test. The studied cyanide complexes have been shown to decrease the viability of HeLa cells with IC50 values 14.86, 6.5, 7.2 and 19.2 µg/ml for C1, C2, C3 and C4 complex, respectively
A linear programming-based method for job shop scheduling
We present a decomposition heuristic for a large class of job shop scheduling problems. This heuristic utilizes information from the linear programming formulation of the associated optimal timing problem to solve subproblems, can be used for any objective function whose associated optimal timing problem can be expressed as a linear program (LP), and is particularly effective for objectives that include a component that is a function of individual operation
completion times. Using the proposed heuristic framework, we address job shop scheduling problems with a variety of objectives where intermediate holding costs need to be explicitly considered. In computational testing, we demonstrate the performance of our proposed solution approach
Effect of Co-60 gamma-ray irradiation on electrical properties of Ti/Au/GaAs1-xNx Schottky diodes
Current-voltage (I-V), capacitance-voltage-frequency (C-V-f) and conductance-voltage-frequency (G/ω-V-f) measurements at room temperature are used to study 50 kGy 60Co γ-ray electrical properties irradiation dependence of Ti/Au/GaAs1−xNx Schottky diodes with 0.2%; 0.4%; 0.8% and 1.2% nitrogen dilution. This γ-ray irradiation induces a permanent damage that has increased ideality factor and series resistance for all samples. It was accompanied by a decrease in Schottky barrier height with nitrogen content up to 0.4%N and remained constant thereafter. Radiation was also found to degrade the reverse leakage current.
At high frequency (1 MHz), capacitance and conductance decreased after radiation due to a decrease in net doping concentration. Interface state density and series resistance were determined from C-V-f and G/ω-V-f characteristics using Hill-Coleman methods. Interface states density exponentially decreased with increasing frequency confirming the behavior of interface traps response to ac signal.
Series resistance increases after irradiation is attributed to carrier's removal effect and mobility degradation. It has two peaks in the accumulation and inversion region for some diodes (0.4%N, 0.8%N). γ-ray irradiation produced traps levels and recombination centers that reduce relaxation time. An increase in %N content can impede irradiation damage with even some compensation when the percent of diluted nitrogen is high (1.2%N)
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