336 research outputs found
Large variations in the hole spin splitting of quantum-wire subband edges
We study Zeeman splitting of zone-center subband edges in a cylindrical hole
wire subject to a magnetic field parallel to its axis. The g-factor turns out
to fluctuate strongly as a function of wire-subband index, assuming values that
differ substantially from those found in higher-dimensional systems. We analyze
the spin properties of hole-wire states using invariants of the spin-3/2
density matrix and find a strong correlation between g-factor value and the
profile of hole-spin polarization density. Our results suggest possibilities
for confinement engineering of hole spin splittings.Comment: 4 pages, 3 figures, RevTex4, to appear in PR
The role of growth regulators, embryo age and genotypes on immature embryo germination and rapid generation advancement in tomato (Lycopersicon esculentum Mill.)
One of the most important problem of tomato breeders is lengthy seed to seed cycle in a breeding program. In vitro techiques provide a lot of advantages for breeders. The objective of this work was to determine the effect of growth regulators and immature embryo age on embryo germination and rapid generation advancement in different tomato genotypes. For this purpose, four different tomato genotypes were used. Immature embryos were derived from fruits 20, 24, 28, 32 and 36 days after pollination. Fruits were left on the plant to mature as control (conventional breeding cycle). MS, MS + 0.1 mg/l kinetin, MS + 0.1 mg/l IAA and MS + 0.1 mg/l kinetin + 0.1 mg/l IAA were used as growth regulators. Growth regulators and genotypes resulted in nonsignificant effect on germination rate and rapid generation advancement, but embryo age resulted in significant effect. Germination rate from immature embryos ranged between 55.22 and 100%. Twenty eight (28) and thirty two (32) days old embryos gave the best germination rate. Days from pollination to flowering, shortened between 53,36 and 63,96 days in comparison with the conventional breeding cycle. This study showed that using immature embryo technique in tomato breeding offers more generation per year when compared to conventional breeding practice.Key words: Growth regulators, immature embryo culture, embryo age, tomato, kinetin, IAA, shortened breeding cycle
Synthesis and dye sensitized solar cell applications of Bodipy derivatives with bis-dimethylfluorenyl amine donor groups
Three Bodipy dyes with strong absorptivities in the visible and near infrared regions were designed, synthesized and their potential as photosensitizers for liquid electrolyte-based dye sensitized solar cells have been evaluated. For the first time Bodipy derivatives with bis-dimethylfluorenyl amine donor groups which were known for their bulky structures as donor groups have been used together. We altered our mostly used triphenylamine group with these and investigated the dye-sensitized solar cell efficiencies of this new class of Bodipy dyes. © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2015
Heavy metal accumulation in Artemisia and foliaceous lichen species from the Azerbaijan flora
Artemisia plants and foliaceous lichens are known to be capable of accumulating heavy metals (HM) from soil and air. These plant species are widespread on polluted sites of Azerbaijan. However, so far their capacity to accumulate HM in their shoots and roots has not been tested. Three Artemisia and two lichen species were collected from different contaminated sites of Azerbaijan. Plant and surface soil samples were measured for Cd, Cu, Pb, Ni and Zn concentrations by ICP-AES.The results indicated that among the Artemisia species A. scoparia showed the best HM accumulation properties. Lichen species were also distinguished by very high amounts of HM in their biomass, while in surrounding soil samples HM concentrations had higher contents than the soils occupied only with Artemisia species.The results indicate that on contaminated sites Artemisia and lichens accumulated metals in their biomass without toxicity symptoms. Taking large biomass and high adaptation ability into account, A. scoparia represents a good tool for a phytoremediation approach on polluted soils
Effect of annual and quarterly financial statement announcements on trading volume and return variability in ISE
Ankara : Department of Management and Graduate School of Business Administration of Bilkent University, 1996.Thesis (Master's) -- Bilkent University, 1996.Includes bibliographical references leaves 22-24Announcements of financial statement informations provide valuable signals for investors. There are evidences documenting the changes in trading volume and stock returns at the time of annual and interim financial statement announcements in comparison to those in non-announcement periods. The purpose of this study is to analyse the effect of the quarterly and annual financial statement announeements on trading volume and security return variability in the Turkish stock market. The testing period covers the suceessive three interim announeement periods and the annual statements of the years 1991 through 1994.Çakmak, S SerdarM.S
Quantum correlations in a few-atom spin-1 Bose-Hubbard model
We study the thermal quantum correlations and entanglement in spin-1 Bose-Hubbard model with two and three particles. While we use negativity to calculate entanglement, more general non-classical correlations are quantified using a new measure based on a necessary and sufficient condition for zero-discord state. We demonstrate that the energy level crossings in the ground state of the system are signalled by both the behavior of thermal quantum correlations and entanglement
Intracellular expression of FLT3 in Purkinje cells: implications for adoptive T-cell therapies
CA-125/CEA ratio as a prognostic factor in type II endometrial cancer: a single institute experience
Objective: Type II (non-endometrioid) endometrial cancer is less common with an incidence of 10%-20%. It has an aggressive clinical course with heterogeneous clinic pathological features. The aim of this study is to evaluate prognostic factors and survival outcomes in type II endometrial cancer.
Patients and Methods: Patients aged over 18 years with diagnosis of Stage IA-IVB type II endometrial cancer were included to the study. Between 2013 and 2019, a total of 76 patients were evaluated retrospectively.
Results: Median overall survival (OS) was 25 months while median disease-free survival (DFS) was 22 months. Median DFS was 25 months (95% CI: 14.71-35.28) in patients with negative lymph nodes while it was 10 months (95% CI: 6.88-13.11) in patients with positive lymph nodes (p=0.017). Median OS was 28 months (95% CI: 23.05-32.95) in patients with a ratio of CA-125/CEA<25 while it was 16 months (95% CI: 5.19-26.80) in those with a ratio of CA-125/CEA≥25 (p=0.02). Patients with an Eastern Cooperative Oncology Group performance score (ECOG PS) <2 at the time of diagnosis had a significantly longer OS than ECOG PS≥2 [median 29 months (95% CI: 22.99-35.94) vs. 15 months (95% CI: 0.33-29.66); p=0.024]. In multivariate Cox regression analysis CA-125/CEA (HR:1.70, 95% CI: 1.01-2.83, p=0.042) was independent risk factor for OS.
Conclusions: CA-125/CEA ratio may have prognostic significance in type 2 endometrial cancer, but it needs to be supported by randomized clinical trials
- …