Non equilibrium anisotropic excitons in atomically thin ReS2_2

We present a systematic investigation of the electronic properties of bulk and few layer ReS$_2$ van der Waals crystals using low temperature optical spectroscopy. Weak photoluminescence emission is observed from two non-degenerate band edge excitonic transitions separated by $\sim$ 20 meV. The comparable emission intensity of both excitonic transitions is incompatible with a fully thermalized (Boltzmann) distribution of excitons, indicating the hot nature of the emission. While DFT calculations predict bilayer ReS$_2$ to have a direct fundamental band gap, our optical data suggests that the fundamental gap is indirect in all cases

Luminescent and scintillation properties of Ce3+ doped Ca2RMgScSi3O12 (R = Y, Lu) single crystalline films

The work is dedicated to the growth and investigation of the luminescent and scintillation properties of single crystalline films (SCFs) of Ca2-xR1+xMg1+xSc1-xSi3O12:Ce (R = Y, Lu) mixed garnets with x = 0-0.25, grown using the liquid phase epitaxy method onto Y3Al5O12 substrates from PbO-B2O3 based flux. The absorption, luminescent and scintillation properties of Ca2-xY1+xMg1+xSc1-xSi3O12:Ce and Ca2-xLu1+xMg1+xSc1-xSi3O12:Ce SCFs with x = 0 and 0.25 were investigated and compared with the reference YAG:Ce and LuAG:Ce SCFs. Using the Ca2+, Mg2+ and Si4+ alloying, the Ce3+ emission spectra in Ca2-xR1+xMg1+xSc1-xSi3O12:Ce (R = Y, Lu; x = 0-0.25) SCFs can be notably extended in the red range in comparison with YAG: Ce and LuAG: Ce SCFs due to the increase of crystal field strength and Ce3+ multicenter creation in the dodecahedral positions of the lattices of these mixed garnet compounds. Due to the formation of Ce4+ ions, the as-grown Ca2-xR1+xMg1+xSc1-xSi3O12:Ce (R = Y, Lu) SCFs at x = 0 and 0.25 show relatively low light yield. However, after annealing in reducing atmosphere (95% N-2 + 5% H-2) at T > 1000 degrees C, a recharging Ce4+ -> Ce3+ takes place. After that, these SCFs possess the light yield about of 30% and 31% in comparison with the reference YAG: Ce and LuAG: Ce SCFs, respectively, and a fast scintillation response with the decay times in the ns range under a-particles excitation by Pu-239 (5.15 MeV) source

Non equilibrium anisotropic excitons in atomically thin ReS2

We present a systematic investigation of the electronic properties of bulk and few layer ReS2 van der Waals crystals using low temperature optical spectroscopy. Weak photoluminescence emission is observed from two non-degenerate band edge excitonic transitions separated by similar to 20 meV. The comparable emission intensity of both excitonic transitions is incompatible with a fully thermalized (Boltzmann) distribution of excitons, indicating the hot nature of the emission. While DFT calculations predict bilayer ReS2 to have a direct fundamental band gap, our optical data suggests that the fundamental gap is indirect in all cases

Stromal myofibroblasts in breast cancer: relations between their occurrence, tumor grade and expression of some tumour markers

It is suggested that tumour stromal myofibroblasts exert an unfavourable effect on the biology of breast cancer. We are aware of only a single study which examined relationships between manifestation of myofibroblasts in the stroma of breast cancer and clinicopathological data of the patients. The present study was aimed at estimation of the effect exerted by myofibroblasts present in the tumour stroma on principal pathological parameters and on expression of Ki67, P53 and HER-2 proteins in the group of the most frequent breast cancers, the ductal cancers. In paraffin sections of 60 ductal breast cancers (20 cases in G1, 20 in G2 and 20 in G3), immunohistochemical reactions were performed to detect expression of smooth muscle actin (SMA) in order to visualize myofibroblasts, Ki67, P53 and HER-2. The studies demonstrated that the most numerous myofibroblasts were present in G3 cases and they were the least frequent in G1 cases (P = 0.02). Positive correlations were observed between the presence of myofibroblasts in tumour stroma and expression of Ki67 and HER-2 in breast cancer cells in the entire group (P < 0.001 and P = 0.001, respectively), in G2 cases (P = 0.003 and P = 0.03) and in G3 cases (P = 0.01 and P = 0.03). Considering that the higher grade, Ki67 and HER-2 are thought to represent unfavourable prognostic factors, the elevated content of myofibroblasts in tumour stroma is probably typical for cases with worse prognosis

Iron status and survival in diabetic patients with coronary artery disease

Objective-To investigate the impact of iron status on survival in patients with type 2 diabetes and coronary artery disease (CAD). Research Design and Methods-Serum ferritin, transferrin saturation (Tsat), and soluble transferrin receptor (sTfR) were measured in 287 patients with type 2 diabetes and stable CAD (65 ± 9 years of age, 78% men). Results-During a mean follow-up of 45 ± 19 months, there were 59 (21%) deaths and 60 (21%) cardiovascular hospitalizations. Both serum ferritin and sTfR strongly predicted 5-year all-cause mortality rates, independently of other variables (including hemoglobin, measures of renal function, inflammation, and neurohormonal activation). There was an exponential relationship between sTfR and mortality (adjusted hazard ratio [HR] per 1 log mg/L · 4.24 [95% CI 1.43-12.58], P = 0.01), whereas the relationship between ferritin and mortality was U-shaped (for the lowest and the highest quintiles vs. the middle quintile [reference group], respectively: adjusted HR 7.18 [95% CI 2.03-25.46], P = 0.002, and adjusted HR 5.12 [1.48-17.73], P = 0.01). Similar patterns were observed for the composite outcome of all-cause mortality or cardiovascular hospitalization, and in these multivariable models, low Tsat was related to unfavorable outcome. Conclusions-Both low and high serum ferritin (possibly reflecting depleted and excessive iron stores, respectively) along with high serum sTfR (reflecting reduced metabolically available iron) identify patients with type 2 diabetes and CAD who have a poor prognosis. © 2013 by the American Diabetes Association

Numerical and experimental investigation of a small gas turbine combustor

Workshop byl částečně podpořen projektem CZ.1.07/2.3.00/20.0139. Tento projekt je spolufinancován Evropským sociálním fondem a státním rozpočtem České republiky

Numerical investigations of aviation fuel combustion in the turbine engine GTM-140

Artykuł przedstawia trójwymiarowe obliczenia numeryczne spalania w miniaturowym silniku turbinowym GTM-140. Głównym celem pracy jest zrozumienie procesów zachodzących w zastosowanej komorze spalania. Została przeprowadzona analiza strat przepływu w silniku turbinowym. Przedstawiono wyniki w postaci pól temperatury, ciśnienia oraz prędkości z uwzględnieniem przepływu cold flow oraz przepływu reakcyjnego. Został użyty model turbulencji k-s (RANS), jako model spalania posłużył Non-Premixed Equilibrium Model oraz Dicrete Phase Model jako model z odparowaniem kropel paliwa.This article presents three-dimensional numerical calculations of combustion in the GTM-140 miniature turbine engine. The main aim of this work is to understand the processes occurring in the combustion chamber. Flow losses analysis in the turbine engine was conducted. The paper shows the results as the fields of temperature, pressure and velocity including the "coldflow" and the flow with reaction. The k-s (RANS) Turbulence Model and Non-Premixed Equilibrium Model for combustion was used. The particles of fluid droplets were described by the Discrete Phase Model