147 research outputs found

    Soft supersymmetry breaking with tiny cosmological constant in flux compactified N=1 Supergravity

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    Using the flux compactification scenario in a generic supergravity model we construct a set of conditions which are necessary to generate de-Sitter or anti de-Sitter vacua for appropriate choices of the parameters in superpotential. It is shown that a mass spectrum consistent with softly broken TeV scale supersymmetry in a minimal supersymmetric standard model at the observable sector can be obtained along with a tiny cosmological constant when the Kahler and superpotential of the hidden sector satisfy a set of general constraints. Constructing a specific model with Kahler and superpotentials which satisfy the above constraints, it is demonstrated that all the hidden sector fields have vacuum expectation values close to Planck scale and the resulting low energy potential does not have any flat direction.Comment: 20 pages, 1 figur

    Profil ekspresije receptora hormona rasta (GHR), receptora ÄŤimbenika rasta sliÄŤnog inzulinu (IGFR) i gena leptina s biokemijskim i endokrinim profilom u jaradi crne bengalske koze (Capra hircus) tijekom razliÄŤitih razdoblja pretpubertetskog rasta

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    The aim of this study was to evaluate the expression profile of growth hormone receptor (GHR), insulin like growth factor receptor (IGFR) and leptin genes, together with some blood biochemical (glucose, aspartate aminotransferase, AST; alanine aminotransferase, ALT) and endocrine (growth hormone and cortisol) parameters. For this purpose, blood samples were collected from 25 male and 25 female kids of the Black Bengal goat (Capra hircus), at days 15, 30, 60, 90, 120 and 150. Male kids gained more body weight compared to females. The glucose and cortisol levels significantly (P≤0.01) decreased with the advancement of age. AST, ALT, and growth hormone increased significantly (P≤0.01). In both sexes, plasma glucose level was negatively (P≤0.01) correlated with AST. In males both cortisol and GH levels were positively (P≤0.05) correlated with plasma glucose levels. In female kids only GH showed a positive (P≤0.05) correlation with glucose levels. Female kids had greater expression of the GH receptor, IGFR mRNA and Leptin mRNA on day 30 (P≤0.05) and day 150 (P≤0.01). GHR was only positively (P≤0.05) correlated with IGFR and LEP in female kids. On the basis of the results obtained from our research, we are able to conclude that the lower growth rate in female kids expressed more leptin, which stimulated the somatotrophic axis for the expression of GHR and IGFR during the prepubertal growth stage.Cilj istraživanja bio je procijeniti profil ekspresije receptora hormona rasta (GHR), receptora čimbenika rasta sličnog inzulinu (IGFR) i gena leptina zajedno s krvnim biokemijskim pokazateljima (glukoza, aspartat-aminotransferaza AST, alanin-aminotransferaza ALT) i endokrinim pokazateljima (hormon rasta i kortizol). U tu su svrhu 15., 30., 60., 90., 120. i 150. dan života uzeti su uzorci krvi od 25 muške i 25 ženske jaradi crne bengalske koze (Capra hircus). Muška je jarad imala veći prirast tjelesne mase u usporedbi sa ženskom. Razine glukoze i kortizola s porastom dobi znakovito su se smanjivale (P ≤ 0,01). AST, ALT i hormon rasta znakovito su porasli (P ≤ 0,01). Kod oba je spola razina glukoze u plazmi bila u negativnoj korelaciji (P ≤ 0,01) s AST-om. Kod muške su jaradi kortizol i hormon rasta bili u pozitivnoj korelaciji (P ≤ 0,05) s razinama glukoze u plazmi. Samo je u ženske jaradi hormon rasta pokazao pozitivnu korelaciju (P ≤ 0,05) s razinama glukoze. Ženska je jarad imala veću ekspresiju receptora hormona rasta, mRNA IGFR i mRNA leptina 30. dan (P ≤ 0,05) i 150. dan (P ≤ 0,01). GHR je bio u pozitivnoj korelaciji (P ≤ 0,05) samo s IGFR-om i leptinom u ženske jaradi. Na temelju rezultata ovoga istraživanja možemo zaključiti da niža stopa rasta u ženske jaradi dovela do veće ekspresije leptina, što je stimuliralo somatotropnu os za ekspresiju hormona rasta i IGFR-a u pretpubertetskom razdoblju

    Quantum noise limited microwave amplification using a graphene Josephson junction

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    Josephson junctions (JJ) and their tunable properties, including their nonlinearities, form the core of superconducting circuit quantum electrodynamics (cQED). In quantum circuits, low-noise amplification of feeble microwave signals is essential and the Josephson parametric amplifiers (JPA) are the widely used devices. The existing JPAs are based on Al-AlOx-Al tunnel junctions realized in a superconducting quantum interference device geometry, where magnetic flux is the knob for tuning the frequency. Recent experimental realizations of 2D van der Waals JJs provide an opportunity to implement various cQED devices with the added advantage of tuning the junction properties and the operating point using a gate potential. While other components of a possible 2D van der Waals cQED architecture have been demonstrated -- quantum noise limited amplifier, an essential component, has not been realized. Here we implement a quantum noise limited JPA, using a graphene JJ, that has linear resonance gate tunability of 3.5 GHz. We report 24 dB amplification with 10 MHz bandwidth and -130 dBm saturation power; performance on par with the best single-junction JPAs. Importantly, our gate tunable JPA works in the quantum-limited noise regime which makes it an attractive option for highly sensitive signal processing. Our work has implications for novel bolometers -- the low heat capacity of graphene together with JJ nonlinearity can result in an extremely sensitive microwave bolometer embedded inside a quantum noise-limited amplifier. In general, our work will open up exploration of scalable device architecture of 2D van der Waals materials by integrating a sensor with the quantum amplifier.Comment: 15 pages, 4 figures, and supplementary informatio

    Repurposing of Drugs–The Ketamine Story

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    Aliphatic Diazirines as Photoaffinity Probes for Proteins: Recent Developments

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    Analytical models for accelerating FPGA architecture development

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    Field-Programmable Gate Arrays (FPGAs) are widely used to implement logic without going through an expensive fabrication process. Current-generation FPGAs still suffer from area and power overheads, making them unsuitable for mainstream adoption for large volume systems. FPGA companies constantly design new architectures to provide higher density, lower power consumption, and faster implementation. An experimental approach is typically followed for new architecture design, which is a very slow and computationally expensive process. This dissertation presents an alternate faster way for FPGA architecture design. We use analytical model based design techniques, where the models consist of a set of equations that relate the effectiveness of FPGA architectures to the parameters describing these architectures. During early stage architecture investigation, FPGA architects and vendors can use our equations to quickly short-list a limited number of architectures from a range of architectures under investigation. Only the short-listed architectures need then be investigated using an expensive experimental approach. This dissertation presents three contributions towards the formulation of analytical models and the investigation of capabilities and limitations of these models. First, we develop models that relate key FPGA architectural parameters to the depth along the critical path and the post-placement wirelength. We detail how these models can be used to estimate the expected area of implementation and critical path delay for user-circuits mapped on FPGAs. Secondly, we develop a model that relates key parameters of the FPGA routing fabric to the fabric's routability, assuming that a modern one-step global/detailed router is used. We show that our model can capture the effects of the architectural parameters on routability. Thirdly, we investigate capabilities and limitations of analytical models in answering design questions that are posed by the FPGA architects. Comparing with two experimental approaches, we demonstrate that analytical models can better optimize FPGA architectures while requiring significantly less design effort. However, we also demonstrate that the analytical models, due to their continuous nature, should not be used to answer the architecture design questions related to applications having `discrete effects'.Applied Science, Faculty ofElectrical and Computer Engineering, Department ofGraduat
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