Two Dimensional Spin-Polarized Electron Gas at the Oxide Interfaces

The formation of a novel spin-polarized 2D electron gas at the LaMnO$_3$ monolayer embedded in SrMnO$_3$ is predicted from the first-principles density-functional calculations. The La (d) electrons become confined in the direction normal to the interface in the potential well of the La layer, serving as a positively-charged layer of electron donors. These electrons mediate a ferromagnetic alignment of the Mn t$_{2g}$ spins near the interface via the Anderson-Hasegawa double exchange and become, in turn, spin-polarized due to the internal magnetic fields of the Mn moments.Comment: 5 pages, 6 figure

Strain and Electric Field Modulation of the Electronic Structure of Bilayer Graphene

We study how the electronic structure of the bilayer graphene (BLG) is changed by electric field and strain from {\it ab initio} density-functional calculations using the LMTO and the LAPW methods. Both hexagonal and Bernal stacked structures are considered. The BLG is a zero-gap semiconductor like the isolated layer of graphene. We find that while strain alone does not produce a gap in the BLG, an electric field does so in the Bernal structure but not in the hexagonal structure. The topology of the bands leads to Dirac circles with linear dispersion in the case of the hexagonally stacked BLG due to the interpenetration of the Dirac cones, while for the Bernal stacking, the dispersion is quadratic. The size of the Dirac circle increases with the applied electric field, leading to an interesting way of controlling the Fermi surface. The external electric field is screened due to polarization charges between the layers, leading to a reduced size of the band gap and the Dirac circle. The screening is substantial in both cases and diverges for the Bernal structure for small fields as has been noted by earlier authors. As a biproduct of this work, we present the tight-binding parameters for the free-standing single layer graphene as obtained by fitting to the density-functional bands, both with and without the slope constraint for the Dirac cone.Comment: 7 pages, 7 figure

Designing Verbal Message And Visual Media Of Quick Chicken

Quick Chicken currently exists on more than 8 islands, more than 17 provinces, more than 220 outlets. Compared to similar fried chicken outlets, Quick Chicken outlet designs are more attractive because they use the concept of selling in containers. The advantages of Quick Chicken are offering a menu that is a combination of traditional and western, in addition, Quick Chicken also offers larger pieces of chicken than its competitors, namely Hisana and Sabana. Currently Quick Chicken is experiencing a decline in sales. This happens because the promotion done has not been able to make the target audience aware and loyal. The question research is how to design verbal message and visual media as the solustion for the problem above. Semantics is used to define the verbal message, while advertising theory is used as the the grand theory of visual media. The methode used is qualitative descriptif. The result is as the recommendation design of the verbal message and visual media as the solution for the problem using AISAS. The conclusion is with the design of Quick Chicken promotion, it is hoped that being able to be a solution to identified problems, and it can also be a reference for similar problems as well. Key Words: Semantics, verbal message, Visual Media, Quick Chicke

Networking frictions in venture capital, and the gender gap in entrepreneurship

We find that male participants in Harvard Business School’s New Venture Competition who were randomly exposed to more VC investors on their panel were substantially more likely to start a VC-backed startup post-graduation, indicating that access to investors impacts fundraising independent of the quality of ideas. However, female participants experience no benefit from exposure to male or female VCs, which appears related to a reduced propensity to reach out to VCs to whom they were exposed. Our results therefore also demonstrate gender-based differences in the degree to which increased exposure to investors can address networking frictions in venture capital

Time for pulse traversal through slabs of dispersive and negative (ϵ\epsilon, μ\mu) materials

The traversal times for an electromagnetic pulse traversing a slab of dispersive and dissipative material with negative dielectric permittivity ($\epsilon$) and magnetic permeability ($\mu$) have been calculated by using the average flow of electromagnetic energy in the medium. The effects of bandwidth of the pulse and dissipation in the medium have been investigated. While both large bandwidth and large dissipation have similar effects in smoothening out the resonant features that appear due to Fabry-P\'{e}rot resonances, large dissipation can result in very small or even negative traversal times near the resonant frequencies. We have also investigated the traversal times and Wigner delay times for obliquely incident pulses and evanescent pulses. The coupling to slab plasmon polariton modes in frequency ranges with negative $\epsilon$ or $\mu$ is shown to result in large traversal times at the resonant conditions. We also find that the group velocity mainly contributes to the delay times for pulse propagating across a slab with n=-1. We have checked that the traversal times are positive and subluminal for pulses with sufficiently large bandwidths.Comment: 9 pages, 9 figures, Submitted to Phys. Rev.

Monthly Pattern and Distribution of Births in a Teaching Institution of Northern India

Background: Seasonality in frequency of birth is a world-wide phenomenon that reflect behavioral and biological determinant of reproduction. Aim: To assess pattern of birth occurring in a medical college hospital according to calendar months. Materials and Methods: Log books of delivery room were retrieved and all singleton live births occurring in each month for the calendar years 2002-2009 (8-year) was extracted. Data collection was carried out by the investigators during the period February-April 2010 and data management using software statistical package. Analysis was carried out by calculating average birth per month for the period under study and standard index as well as quarter-wise details was also tabulated. Result: It was observed that there was a progressive rise in total number of births occurring in the hospital from 5840 (avg. 486.66/month) from the year 2002 to 8205 (avg. 683.75/month) in 2009. Maximum birth occurred during the months of August (avg. 774/month) followed by September (avg. 735/month) and October (avg. 705/month) respectively and least in the month of April (avg. 445/month) with a P<0.05. Quarter (q) wise distribution showed maximum birth during q3 (July-September=30%) followed by q4 (October- December=27%), q2 (April-June=22%) and q1 (January-March=21%) respectively. Conclusion: It can be concluded that peak birth in the months of August-September-October as observed in present study implying that there is increased conception during the winter months of December-January-February. Within study limitations, findings may facilitate advocacy, counseling, planning and delivery of family welfare service in a more efficient and effective manner particularly related to mobilization of human resource, inventory control, logistics, streamlining family planning services at institutional and community level keeping in mind the monthly pattern of hospital deliveries. Keywords: Behavior, communication, conception, delivery, demography, family planning, fertility, human resource, months, pattern, reproduction, seasonality, tim