1,227 research outputs found
A Hyperstable Miniprotein: Additive Effects of D- and L-Ala Substitutions
The effects of alanine substitutions in each helical segment of the structure, and Gly to D-Ala mutations at sites where glycines have positive phi angles in the Trp-cage miniprotein are reported. The effects of the stabilizing mutation were additive, yielding a 20-residue construct (Tm = 83^o^C). Gly to L-Ala substitutions were uniformly destabilizing ([DELTA][DELTA]G~F~ > 11 kJ/mol): the preference for a D-Ala can be as large as 16 kJ/mol. Glycine to D-Ala mutations are validated as a strategy for the design of hyperstable miniprotein scaffolds suitable for stereospecific pharmacophore display
Universal Properties of Linear Magnetoresistance in Strongly Disordered Semiconductors
Linear magnetoresistance occurs in semiconductors as a consequence of strong
electrical disorder and is characterized by nonsaturating magnetoresistance
that is proportional to the applied magnetic field. By investigating a
disordered MnAs-GaAs composite material, it is found that the magnitude of the
linear magnetoresistance (LMR) is numerically equal to the carrier mobility
over a wide range and is independent of carrier density. This behavior is
complementary to the Hall effect that is independent of the mobility and
dependent on the carrier density. Moreover, the LMR appears to be insensitive
to the details of the disorder and points to a universal explanation of
classical LMR that can be applied to other material systems.Comment: Accepted by Phys. Rev. B (2010
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The feminization of love and the indwelling of god: Theological investigations across indic contexts
Our essay is a thematic exploration of the malleability of idioms, imageries, and affectivities of Hindu bhakti across the borderlines of certain Indic worldviews. We highlight the theological motif of the feminine-feminised quest of the seeker (virahiṇī) for her divine beloved in some Hindu expressions shaped by the paradigmatic scriptural text Bhāgavata-purāṇa and in some Punjabi Sufi articulations of the transcendent God’s innermost presence to the pilgrim self. The leitmotif that the divine reality is the “intimate stranger” who cannot be humanly grasped and who is yet already present in the recesses of the virahiṇī’s self is expressed with distinctive inflections both in bhakti-based Vedānta and in some Indo-Muslim spiritual universes. This study is also an exploration of some of the common conceptual currencies of devotional subjectivities that cannot be straightforwardly cast into the monolithic moulds of “Hindu” or “Muslim” in pre-modern South Asia. Thus, we highlight the essentially contested nature of the categories of “Hinduism” and “Indian Islam” by indicating that they should be regarded as dynamic clusters of constellated concepts whose contours have been often reshaped through concrete socio-historical contestations, borrowings, and adaptations on the fissured lands of al-Hind.</jats:p
MIS AND INFORMATION ECONOMICS: AUGMENTING RICH DESCRIPTIONS WITH ANALYTICAL RIGOR IN INFORMATION SYSTEMS DESIGN
Assessing the economic impacts of alternative Information System (IS) designs and selecting IS design parameter values for a given decision setting are two important research issues in the domain of Information Systems. Evaluation studies based on information economics provide rigorous but restricted models, while traditional MIS studies suggest richer but less formal evaluation frameworks. \u27 In this paper, we attempt to combine the analytical rigor and descriptive richness into a unified and consistent basis for evaluating IS designs and making design modifications (improvements) to existing IS. Expanding on the concepts of information economics, a multi-dimensional mathematical model of information quality is developed. Several properties of the quality model with implications for system design are derived in the form of propositions. The impacts of information quality differential upon the effectiveness of an operational level decision setting are investigated through a decision-theoretic approach. Next, a hierarchical model is suggested for relating system design variables to the quality of information generated by the IS. Based on the quality differential impact analysis and the hierarchical model, a structured methodology for making design changes to existing IS is outlined
Effect of Fluid Suction on an Oscillatory MHD Channel Flow with Heat Transfer
Magnetohydrodynamics (MHD) is generally concerned with the study of the magnetic properties (behaviour) of electrically conducting fluids (plasmas, liquid metals etc.) moving in an electromagnetic field. The importance of the concept of MHD in various fields such as astrophysics, bio-medical research, missile technology and geophysics motivates the modelling and investigation of MHD flow and transport problems. The role of fluid suction is paramount in laminar flow control and has wide applications in fields such as aeronautical engineering, automobile engineering and rocket science. This fact inspires the study of the effects of fluid suction in flow and transport models. Time dependent flows are widely encountered in engineering applications such as turbines and in physiological studies such as flow of bio-fluid (blood etc.). In the present paper, an attempt has been made to investigate analytically the problem of a time dependent channel flow with heat transfer, where the channel is bounded by two infinite parallel porous walls. The pressure gradient is assumed to be oscillatory in nature. A magnetic field of uniform strength is assumed to be applied normal to the walls. After necessary idealization of the momentum and energy equations, the governing equations of our problem are solved by adopting the regular perturbation technique. The effects of magnetic field, suction velocity, viscous dissipation, Reynolds number, Prandtl number etc. on the flow and heat transfer are studied and demonstrated graphically. It is seen that magnetic field, fluid suction, viscous dissipation, Reynolds number, Prandtl number have a significant effect on the flow and heat transfer characteristic. For instance, the imposition of the magnetic field enhances the rates of heat transfer at the walls and the fluid suction decreases the temperature and aids in laminar flow control
Anti-inflammatory effect of low intensity ultrasound (LIUS) on complete Freund's adjuvant-induced arthritis synovium
SummaryObjectivesArthritis with intra-articular inflammation was accompanied by joint pain, swelling, and stiffness leading to significant functional impairment. Thus, regulation of joint inflammation is a good therapeutic approach for patients with arthritis. In this study, the effect of low intensity ultrasound (LIUS) applied to an adjuvant-induced arthritic rat model on the synovium was investigated.DesignSynovial inflammation was induced by complete Freund's adjuvant (CFA)-injection into the rat knee joint. LIUS (200 mW/cm2) was applied on the ipsilateral knee everyday for 10 min beginning 1 day after inflammation induction. The expression of proinflammatory factors and immunohistochemical staining pattern of the synovium were assessed.ResultsCFA induced an increase of the knee circumference that was significantly diminished by LIUS. Synovial membrane hyperplasia in the ipsilateral joint was also affected by LIUS. The inflammatory mediators, COX-1/2, IL-1β, and iNOS, but not TNF-α, in the synovial membrane were induced after 3 days, and they closely correlated with the degree of edema. In the synovial membrane, the expression of inflammatory mediators was reduced by LIUS. The chemoattractant chemokine receptor CCR5 also was involved. On immunohistochemical analysis, CFA caused increased infiltration of CD11b-positive cells in the synovium. After 3 days, neutrophils, myeloperoxidase (MPO)-positive cells filled the inflammatory core; later, monocytes and macrophages, ionized calcium binding adaptor molecule 1 (Iba1)-positive cells in the periphery infiltrated the core by day 5. LIUS markedly reduced CFA-induced inflammatory cells infiltration.ConclusionLIUS showed a potent anti-inflammatory effect in this animal arthritis model with reduced infiltration of inflammatory cells into the synovium
Survey of LTE Downlink Schedulers Algorithms in Open Access Simulation Tools NS-3 and LTE-SIM
The LTE/LTE-A has become a catchphrase for research and lot of research are being conducted and carried out in LTE in various issues by various people. New tools are developed and introduced in the market to interpret the results of the new algorithms proposed by various people. Some tools are open access which are free to use but some tools are produced by the companies which are not open access. In this paper some of the open access simulation tools like LTE-Sim and NS-3 are analyzed and LTE downlink scheduler algorithms are simulated using those tools. In LTE systems, the downlink scheduler is an important component for radio resource management; hence in the context of LTE simulation, a study between the downlink scheduler models between the simulators are performed
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