Optical/IR studies of Be stars in NGC 6834 with emphasis on two specific stars

We present optical and infrared photometric and spectroscopic studies of two Be stars in the 70--80-Myr-old open cluster NGC 6834. NGC 6834(1) has been reported as a binary from speckle interferometric studies whereas NGC 6834(2) may possibly be a gamma Cas-like variable. Infrared photometry and spectroscopy from the United Kingdom Infrared Telescope (UKIRT), and optical data from various facilities are combined with archival data to understand the nature of these candidates. High signal-to-noise near-IR spectra obtained from UKIRT have enabled us to study the optical depth effects in the hydrogen emission lines of these stars. We have explored the spectral classification scheme based on the intensity of emission lines in the $H$ and $K$ bands and contrasted it with the conventional classification based on the intensity of hydrogen and helium absorption lines. This work also presents hitherto unavailable UBV CCD photometry of NGC 6834, from which the evolutionary state of the Be stars is identified.Comment: Published in Research in Astronomy and Astrophysics, RAA 14 (2014) 1173-1192, 20 pages, 10 figure

Secretion of fatty and albuminous yolk by Golgi bodies in Stomopneustes variolaris, Lamarck

1. The Golgi bodies in the oocytes of Stomopneustes secrete both fatty and albuminous yolk grains. 2. The Golgi vasicle enlarges into a vacuole inside which fatty yolk appears to be deposited. The Golgirim does not undergo any transformation. 3. Prior to secretion of albuminous yolk the mitochondria clump together. The Golgi vesicles by rupture give rise to scale or batonette like bodies. These attach themselves to the mitochondrial clumps and secrete albuminous yolk. The mitochondria in the fully developed yolk spheres are yolky. 4. The origin of both fatty and albuminous yolk in relation with the Golgi bodies only confirms the belief that the nature of the action of the apparatus is only by means of enzymes and that fat, fatty yolk and yolk are only secondary products resulting from the action of these enzymes on materials derived from mitochondria, cytoplasm, nucleolus, etc

Implementing Virtual Pair Programming in E-Learning Environment

Programming subjects are one of the core and important subjects that should be taken by students majoring in information system or computing. The problem of teaching and learning of programming has been widely reported in literatures. Many attempts have been made to solve this problems and this has led to many new approaches in teaching and learning of programming. One of the approach that has been proposed is the use of pair-programming, which is one of the practice of eXtreme Programming (XP). The advent of e-learning has given birth to the idea of Virtual Pair Programming (VPP). This paper describes how asynchronous mode of collaboration using VPP could be implemented for e-learning learners to learn programming

Electrical transport and low-temperature scanning tunneling microscopy of microsoldered graphene

Using the recently developed technique of microsoldering, we perform a systematic transport study of the influence of PMMA on graphene flakes revealing a doping effect of up to 3.8x10^12 1/cm^2, but a negligible influence on mobility and gate voltage induced hysteresis. Moreover, we show that the microsoldered graphene is free of contamination and exhibits a very similar intrinsic rippling as has been found for lithographically contacted flakes. Finally, we demonstrate a current induced closing of the previously found phonon gap appearing in scanning tunneling spectroscopy experiments, strongly non-linear features at higher bias probably caused by vibrations of the flake and a B-field induced double peak attributed to the 0.Landau level of graphene.Comment: 8 pages, 3 figure

Formation of multinuclear cells in leprous lesions

This article does not have an abstract

Some observations on Mycobacterium leprae

This article does not have an abstract

Temporary Redundant Transmission Mechanism for SCTP Multihomed Hosts

In SCTP’s Concurrent Multipath Transfer, if data is sent to the destined IP(s) without knowledge of the paths condition, packets may be lost or delayed. This is because of the bursty nature of IP traffic and physical damage to the network. To offset these problems, network path status is examined using our new mechanism Multipath State Aware Concurrent Multipath Transfer using redundant transmission (MSACMT-RTv2). Here the status of multiple paths is analyzed, initially and periodically thereafter transmitted. After examination, paths priority is assigned before transmission. One path is temporarily employed as redundant path for the failure-expected path (FEP); this redundant path is used for transmitting redundant data. At the end of predefined period, reliability of the FEP is confirmed. If FEP is ensured to be reliable, temporary path is transformed into normal CMT path. MSACMT-RTv2 algorithm is simulated using the Delaware University ns-2 SCTP/CMT module (ns-2; V2.29). We present and discuss MSACMT-RTv2 performance in asymmetric path delay and with finite receiver buffer (rbuf) size. We extended our experiment to test robustness of this algorithm and inferred exhaustive result. It is inferred that our algorithm outperforms better in terms of increasing the throughput and reducing the latency than existing system

Analysis of harmonics using wavelet technique

This paper develops an approach based on wavelet technique for the estimation of harmonic presents in power system signals. The proposed technique divides the power system signals into different frequency sub-bands corresponding to the odd harmonic components of the signal. The algorithm helps to determine both the time and frequency information from the harmonic frequency bands. The comparative study will be done with the input and the results attained from the wavelet transform (WT) for different conditions and Simulation results are given

Relationship between transformational leadership, organizational structure and knowledge management

The study examines the relationships between transformational leadership style, knowledge management and organizational structure among 255 administrators in a public university in Malaysia. The findings of this study reveal that transformational leadership style is a vital in promoting knowledge management practices in an organization.Specifically, the result of this study reveals that idealized influence, inspirational motivation, intellectual stimulation and individualized consideration of transformational leadership style significantly influence knowledge management practices. The organizational structure was found to moderate the effect of transformational leadership on knowledge management indicating that organizational structure plays a crucial role in assisting the leaders to manage knowledge across the organization

A study of the role of Lyman {\beta} fluorescence on OI line strengths in Be stars

The possibility of the Ly{\beta} fluorescence mechanism being operational in classical Be stars and thereby contributing to the strength of the OI 8446 {\AA} line has been recognized for long. However this supposition needs to be quantified by comparing observed and predicted OI line ratios. In the present work, optical and near-infrared spectra of classical Be stars are presented. We analyse the observed strengths of the OI 7774, 8446, 11287 and 13165 {\AA} lines which have been theoretically proposed as diagnostics for identifying the excitation mechanism. We have considered and examined the effects of Ly{\beta} fluorescence, collisional excitation, recombination and continuum fluorescence on these OI line strengths. From our analysis it appears that the Ly{\beta} fluorescence process is indeed operative in Be stars.Comment: Accepted for publication in ApJ main journal, 19 pages, 5 figure