Self-imaging silicon Raman amplifier

We propose a new type of waveguide optical amplifier. The device consists of collinearly propagating pump and amplified Stokes beams with periodic imaging of the Stokes beam due to the Talbot effect. The application of this device as an Image preamplifier for Mid Wave Infrared (MWIR) remote sensing is discussed and its performance is described. Silicon is the preferred material for this application in MWIR due to its excellent transmission properties, high thermal conductivity, high damage threshold and the mature fabrication technology. In these devices, the Raman amplification process also includes four-wave-mixing between various spatial modes of pump and Stokes signals. This phenomenon is unique to nonlinear interactions in multimode waveguides and places a limit on the maximum achievable gain, beyond which the image begins to distort. Another source of image distortion is the preferential amplification of Stokes modes that have the highest overlap with the pump. These effects introduce a tradeoff between the gain and image quality. We show that a possible solution to this trade-off is to restrict the pump into a single higher order waveguide mode.Comment: 11 pages, 5 figures and 5 sections. Submitted to Optics Expres

Quantum Random Walks do not need a Coin Toss

Classical randomized algorithms use a coin toss instruction to explore different evolutionary branches of a problem. Quantum algorithms, on the other hand, can explore multiple evolutionary branches by mere superposition of states. Discrete quantum random walks, studied in the literature, have nonetheless used both superposition and a quantum coin toss instruction. This is not necessary, and a discrete quantum random walk without a quantum coin toss instruction is defined and analyzed here. Our construction eliminates quantum entanglement from the algorithm, and the results match those obtained with a quantum coin toss instruction.Comment: 6 pages, 4 figures, RevTeX (v2) Expanded to include relation to quantum walk with a coin. Connection with Dirac equation pointed out. Version to be published in Phys. Rev.

A Firm Level Framework for Electronic Commerce: An Information Systems Perspective

Many firms do not have their business plans and information systems plans in place for embarking on electronic commerce. A firm level framework for electronic commerce will help firms to plan and align their ECIS (Electronic Commerce Information Systems) to business and information systems strategies. This paper develops such a framework. The four components of the framework are information architecture, business processes, choice of technology applications, and customer focus. A brief discussion on the significance of these components to electronic commerce is include

A CASE OF MULTIORGAN DYSFUNCTION DUE TO SCRUB TYPHUS INFECTION

Rickettsia tsutsugamushi causes an acute febrile illness known as scrub thypus. Humans get infected when they accidentally encroach the mite infested areas (mite islands) mainly in rural and sub-urban areas1. Scrub typhus is being increasingly reported in India. It should be considered in the differential diagnosis of patients with acute febrile illness, including those with thrombocytopenia, abnormalities in liver function tests, altered sensorium, atypical pneumonia, acute respiratory distress syndrome. We report a case Multi Organ Dysfunction due to scrub typhus infection. A thorough knowledge of scrub typhus including varied presentations and its complications is important for providing life saving treatment for patients

A CASE OF MULTIORGAN DYSFUNCTION DUE TO SCRUB TYPHUS INFECTION

Rickettsia tsutsugamushi causes an acute febrile illness known as scrub thypus. Humans get infected when they accidentally encroach the mite infested areas (mite islands) mainly in rural and sub-urban areas1. Scrub typhus is being increasingly reported in India. It should be considered in the differential diagnosis of patients with acute febrile illness, including those with thrombocytopenia, abnormalities in liver function tests, altered sensorium, atypical pneumonia, acute respiratory distress syndrome. We report a case Multi Organ Dysfunction due to scrub typhus infection. A thorough knowledge of scrub typhus including varied presentations and its complications is important for providing life saving treatment for patients

Learning preferences of Enrolled Nursing students: Educational preparation and training for workplace readiness

In Australia there are two entry levels in nursing: the Registered Nurse (RN) and the Enrolled Nurse (EN). Nursing education research is predominately focused on higher education for Registered Nurses and postgraduate nursing students; as a result, the educational preferences of Enrolled Nursing students in the vocational education and training (VET) setting have not been identified. Enrolled Nursing students have some distinct educational needs as they transition through education into the workforce due to their diversity in learner characteristics and backgrounds. As the role of this group continues to expand in the workplace to meet the demands of the health workforce, attention to the educational preparation of this cohort of learners is relevant and timely. This requires identifying targeted educational strategies to support learner preferences for the planning and delivery of education to these students. A qualitative research study using focus groups was undertaken to identify specific learner preferences for teaching modalities among Enrolled Nursing students in a Diploma of Nursing program. A thematic analysis of the data identified the following five main themes: a variety of teaching and assessment methods; educator-directed or guided learning; practical application and simulated learning; face-to-face learning; and closer integration of theory to clinical practicum. The main focus of these learners was preparation for workplace settings. The findings have implications for education strategies in the diploma program, in terms of planning the program structure and its delivery; teaching and learning methods; educator development; development of practical and clinical skills; experiential learning; and the promotion of skills for independent and lifelong learning, the latter being essential preparation for professional nursing practice

Effect of humidity on transonic flow

An experimental investigation of the effects of humidity-induced condensation on shock/boundary-layer interaction has been conducted in a transonic wind-tunnel test. The test geometry considered was a wall-mounted bump model inserted in the test section of the wind tunnel. The formation of a λ-shape condensation shock wave was shown from schlieren visualization and resulted in a forward movement of the shock wave, reduced shock wave strength, and reduced separation. Empirical correlations of the shock wave strength and humidity/dew point temperature were established. For humidity levels below 0.15 or a dew point temperature of 268 K, the effect of humidity was negligible. The unsteady pressure measurements showed that if a condensation shock wave formed and interacted with a main shock wave, the flow becomes unsteady with periodic flow oscillations occurring at 720 Hz

Crystal structure of ethyl (2S,2′ R)-1′-benzyl-3-oxo-3H-dispiro[1-benzothio-phene-2,3′-pyrrolidine-2′,11″-indeno-[1,2-b]quinoxaline]-4′-carboxylate

The authors thank the TBI X-ray facility, CAS in Crystallography and BioPhysics, University of Madras, Chennai, India, for the data collection.Peer reviewedPublisher PD

4,9-Dioxa-1,3(1,2)-dibenzena-2(4,5)-1,3-oxazolidinacyclononaphane

The oxazole ring in the title compound, C20H23NO3, adopts an envelope conformation while the 12-membered ring is in a chair conformation. The dihedral angle between the benzene rings is 37.8 (1)°. The crystal structure displays inter­molecular C—H⋯O hydrogen bonding