Increase in the random dopant induced threshold fluctuations and lowering in sub-100 nm MOSFETs due to quantum effects: a 3-D density-gradient simulation study

In this paper, we present a detailed simulation study of the influence of quantum mechanical effects in the inversion layer on random dopant induced threshold voltage fluctuations and lowering in sub-100 mn MOSFETs. The simulations have been performed using a three-dimensional (3-D) implementation of the density gradient (DG) formalism incorporated in our established 3-D atomistic simulation approach. This results in a self-consistent 3-D quantum mechanical picture, which implies not only the vertical inversion layer quantization but also the lateral confinement effects related to current filamentation in the “valleys” of the random potential fluctuations. We have shown that the net result of including quantum mechanical effects, while considering statistical dopant fluctuations, is an increase in both threshold voltage fluctuations and lowering. At the same time, the random dopant induced threshold voltage lowering partially compensates for the quantum mechanical threshold voltage shift in aggressively scaled MOSFETs with ultrathin gate oxides

Antitumor and cytotoxic potential of various extracts of Gloriosa superba L. Centaurea behen L., Elaeocarpus ganitrus Roxb and Ficus religiosa L. against human breast cancer (MDA-MB 231) cell lines

Background: Medicinal plants are rich in a wide variety of secondary metabolites such as tannins, alkaloids, phenolic compounds, flavonoids etc.  which have the capability to inhibit many pathways that lead to cancer. The present study was conducted with the objectives to screen the extracts of dried roots Gloriosa superba L., dried roots of Centaurea behen L. dried fruits/beads of Elaeocarpus ganitrus Roxb., dried leaves of Ficus religiosa L. and investigate their antitumor activity on human breast cancer cell lines (MDA-MB 231). Methods: Cytotoxic activity was evaluated against non-cancerous cell lines (MCF-10A). Hexane, chloroform, methanol and water were the solvents used for extraction of phytoconstituents by Soxhlet method. Anti-proliferative potential of the plant extracts was evaluated using MTT assay. The trypan blue dye exclusion test was used to determine the number of viable cells present in a cell suspension. Results: On MDA MB-231 cell lines, 91.94% cell death was reported with G. superba aqueous extract followed by E. ganitrus methanol extract and F. religiosa hexane extract with 87.93% and 81.61% cell death respectively. Moreover, none of the extracts had shown cytotoxic effect while evaluated against normal non-cancerous cell lines (MCF- 10A). Conclusions: It is inferred from the current findings that phytoconstituents present in the plant extracts have high anticancer potential. These phytoconstituents along with some new anticancer agents present in the plant extracts reflects the high cytotoxic potential against cancer cells

Calcium-binding proteins immunoreactivity in the human subcortical and cortical visual structures

The distribution of neurons and fibers immunoreactive (ir) to the three calcium-binding proteins parvalbumin (PV), calbindin D-28k (CB), and calretinin (CR) was studied in the human lateral geniculate nucleus (LGN), lateral inferior pulvinar, and optic radiation, and related to that in the visual cortex. In the LGN, PV, CR, and CB immunoreactivity was present in all laminae, slightly stronger in the magnocellular than in the parvocellular laminae for CB and CR. PV-ir puncta, representing transversally cut axons, and CR-ir fibers were revealed within the laminae and interlaminar zones, and just beyond the outer border of lamina 6 in the geniculate capsule. In the optic radiation both PV- and CR-immunoreactive neurons, puncta, and fibers were present. CB immunoreactivity was revealed in neurons of all laminae of the lateral geniculate nucleus, including S lamina and interlaminar zones. There were hardly any CB-ir puncta or fibers in the laminae, interlaminar zones, geniculate capsule, or optic radiation. In the lateral inferior pulvinar, immunoreactive neurons for the three calcium-binding proteins were present in smaller number than in the LGN, as well as PV-ir puncta and CR-ir fibers within the nucleus and in the pulvinar capsule. In the white matter underlying area 17, fibers intermingled with a few scattered neurons were stained for both PV and CR, but very rarely for CB. These fibers stopped at the limit between areas 17 and 18. Area 17 showed a dense plexus of PV-ir puncta and neurons in the thalamo-receptive layer IV and CR-ir puncta and neurons both in the superficial layers I-II, IIIC, and in layer VA. Cajal-Retzius CR-ir neurons were present in layer I. CB-ir puncta were almost confined to layer I-III and CB-ir neurons to layer II. Finally the superior colliculus exhibited mostly populations of PV and CR pyramidal-like immunoreactive neurons, mainly in the intermediate tier. These data suggest that in the visual thalamus most calcium-binding protein immunoreactive neurons project to the visual cortex, while in the superior colliculus a smaller immunoreactive population represent projection neuron

Constraints on the Growth and Spin of the Supermassive Black Hole in M32 From High Cadence Visible Light Observations

We present 1-second cadence observations of M32 (NGC221) with the CHIMERA instrument at the Hale 200-inch telescope of the Palomar Observatory. Using field stars as a baseline for relative photometry, we are able to construct a light curve of the nucleus in the g-prime and r-prime band with 1sigma=36 milli-mag photometric stability. We derive a temporal power spectrum for the nucleus and find no evidence for a time-variable signal above the noise as would be expected if the nuclear black hole were accreting gas. Thus, we are unable to constrain the spin of the black hole although future work will use this powerful instrument to target more actively accreting black holes. Given the black hole mass of (2.5+/-0.5)*10^6 Msun inferred from stellar kinematics, the absence of a contribution from a nuclear time-variable signal places an upper limit on the accretion rate which is 4.6*10^{-8} of the Eddington rate, a factor of two more stringent than past upper limits from HST. The low mass of the black hole despite the high stellar density suggests that the gas liberated by stellar interactions was primarily at early cosmic times when the low-mass black hole had a small Eddington luminosity. This is at least partly driven by a top-heavy stellar initial mass function at early cosmic times which is an efficient producer of stellar mass black holes. The implication is that supermassive black holes likely arise from seeds formed through the coalescence of 3-100 Msun mass black holes that then accrete gas produced through stellar interaction processes.Comment: 8 pages, 3 figures, submitted to the Astrophysical Journal, comments welcom

Temperature dependence of iron local magnetic moment in phase-separated superconducting chalcogenide

We have studied local magnetic moment and electronic phase separation in superconducting K$_{x}$Fe$_{2-y}$Se$_2$ by x-ray emission and absorption spectroscopy. Detailed temperature dependent measurements at the Fe K-edge have revealed coexisting electronic phases and their correlation with the transport properties. By cooling down, the local magnetic moment of Fe shows a sharp drop across the superconducting transition temperature (T$_c$) and the coexisting phases exchange spectral weights with the low spin state gaining intensity at the expense of the higher spin state. After annealing the sample across the iron-vacancy order temperature, the system does not recover the initial state and the spectral weight anomaly at T$_c$ as well as superconductivity disappear. The results clearly underline that the coexistence of the low spin and high spin phases and the transitions between them provide unusual magnetic fluctuations and have a fundamental role in the superconducting mechanism of electronically inhomogeneous K$_{x}$Fe$_{2-y}$Se$_2$ system.Comment: 6 pages, 5 figure

Genetics of Durable Resistance to Leaf Rust in Bread Wheat Cultivars Capelle Desprez and Pari 73

Bread wheat cultivars Capelle Desprez and Pari 73 have been showing adult plant leaf rust resistance in India since 20 years. To examine nature, number and mode of inheritance to leaf rust multipathotype tests were conducted on these cultivars along with reference line RL6058 and HD2009 and the susceptible cultivars WL711 and Agra Local at adult plant stages against the eight leaf rust races. F2 and F3 generations from crosses of Capelle Desprez and Pari 73 with susceptible cultivar WL711 were tested for percent disease severity against leaf rust race 77-5 which suggested the presence of three genes in Capelle Desprez and two genes in Pari 73 to leaf rust. Allelic tests using Capelle Desprez with RL6058 indicated the presence of linked genes Lr34/Yr18 however, presence of transgressive segregants in this cross indicated that the other two genes in Capelle Desprez are also involved in leaf rust resistance. The segregation for susceptible plants observed among all the crosses used for allelic tests of Pari 73 for leaf rust indicated that non-hypersensitive resistance genes in Pari 73 are different from those in RL6058, HD2009 and Capelle Desprez. Studies using 536 primers indicated that one of the three rust resistance gene(s) in cultivar Capelle Desprez is located on chromosome 1B, at a distance of 26.3cM from the primer Xgwm 268. Chromosome location of leaf rust resistance gene from cultivar Pari 73 could not be achieved