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Investigating the impact of image content on the energy efficiency of hardware-accelerated digital spatial filters
Battery-operated low-power portable computing devices are becoming an inseparable part of human daily life. One of the major goals is to achieve the longest battery life in such a device. Additionally, the need for performance in processing multimedia content is ever increasing. Processing image and video content consume more power than other applications. A widely used approach to improving energy efficiency is to implement the computationally intensive functions as digital hardware accelerators. Spatial filtering is one of the most commonly used methods of digital image processing. As per the Fourier theory, an image can be considered as a two-dimensional signal that is composed of spatially extended two-dimensional sinusoidal patterns called gratings. Spatial frequency theory states that sinusoidal gratings can be characterised by its spatial frequency, phase, amplitude, and orientation. This article presents results from our investigation into assessing the impact of these characteristics of a digital image on the energy efficiency of hardware-accelerated spatial filters employed to process the same image. Two greyscale images each of size 128 × 128 pixels comprising two-dimensional sinusoidal gratings at maximum spatial frequency of 64 cycles per image orientated at 0° and 90°, respectively, were processed in a hardware implemented Gaussian smoothing filter. The energy efficiency of the filter was compared with the baseline energy efficiency of processing a featureless plain black image. The results show that energy efficiency of the filter drops to 12.5% when the gratings are orientated at 0° whilst rises to 72.38% at 90°
Historic Developments, Current Technologies and Potential of Nanotechnology to Develop Next Generation Solar Cells with Improved Efficiency
Sun is the continuous source of renewable energy, from where we can get abundant of solar energy. Concept of conversionof solar energy into heat was used back in 200 B.C. since then, the solar cells have been developed which can convert solar energy into theelectrical energy and these systems have been produced commercially. The technologies to enhance the power conversion efficiency (PCE)have been continuously improved. Different technologies used for developing solar cells can be categorized either on the basis of materialused or techniques of technology development which is further termed as ‘first generation' (e.g. crystalline silicon), ‘second generation'(thin films of Amorphous silicon, Copper indium gallium selenide, Cadmium telluride), ‘Third generation' (Concentrated, Organic and Dyesensitize solar cell). These technologies give PCE up to 25% depending on the technology and the materials used. Nanotechnology enablesthe use of nanomaterial whose size is below 100 nm with extraordinary properties which has the capability to enhance the PCE to greaterextent. Various nanomaterials like Quantum Dots, Quantum well, carbon nanotubes, Nanowire and graphene have been used to makeefficient and economical solar cells, which not only provide high conversion efficiency economically but also are easy to produce. Today,by using nanotechnology, conversion efficiency up to 44.7 % has been achieved by Fraunhofer Institute at Germany. In this review article,we have reviewed the literature including various patents and publications, summarized the history of solar cell development, developmentof different technologies and rationale of their development highlighting the advantages and challenges involved in their development forcommercial purpose. We have also included the recent developments in solar cell research where different nanomaterials have beendesigned and used successfully to prove their superiority over conventional systems
Generation of human class I major histocompatibility complex activating factor in serum free medium and its partial characterization
Human peripheral blood mononuclear cells (PBMCs) activated with Con-A release a soluble factor which augments the expression of class I major histocompatibility complex (MHC) antigens by a variety of tumour cells. Previous attempts to purify this factor called MHC-activating factor (AF) (MHC-AF) made us realize that the presence of large numbers and quantities of irrelevant fetal calf serum proteins in the culture supernatants of the activated human PBMCs, interfered with the purification procedure. It was therefore necessary to standardize the use of a serum free culture medium to generate human MHC-AF. In the present communication we have tried several types of culture media and have identified DCCM-2 as the most suitable culture medium to generate human MHC-AF. MHC-AF generated in DCCM-2 medium appears to be a protein molecule resistant to pH 2 treatment but sensitive to heat treatment (56°C×45 min) and treatment with proteolytic enzymes trypsin and chymotrypsin
Design, Development and Evaluation of Dendritic Architechture for the Delivery of Ofloxacin against Resistance Producing Strains
Dendrimer represents hyperbranched, monodisperse, three-dimensional macromolecules with host-guest entrapment properties having defined molecular weight. Dendrimer allows defined control of size, shape and position of functional groups. For the above said reason, dendrimers have become more popular application in many fields.The present study was aimed at developing and exploring the use of novel PEGylated 0.5G EDA-PPI (poly propyeleneimine) dendritic architecture for the delivery of an antibacterial drug, Ofloxacin. The dendritic architecture was synthesized by double Michael addiction reaction using ethylenediamine as a core moiety and the synthesized system was PEGylated using PEG-4000 and the Ofloxacin was loaded by equilibrium dialysis method into the system. The prepared Ofloxacin loaded PEGylated 0.5G EDAPPI dendritic architecture was evaluated for FTIR studies, solubility studies, drug entrapment efficiency, in-vitro drug release studies and anti-bacterial assay. The results showed that there was enhanced rate of drug release, drug solubility with significant antimicrobial activity compared to plain Ofloxacin. The tablets of Ofloxacin loaded PEGylated 0.5G EDA-PPI dendrimer were prepared by direct compression method and evaluated for various parameters such as hardness, thickness, weight variation, drug content and in-vitro drug release studies. The in-vitro drug release of Ofloxacin loaded 0.5G EDA-PPI dendrimer compared with that of marketed Ofloxacin tablet. The results revealed that there is enhanced rate of dissolution of Ofloxacin loaded PEGylated 0.5G EDA-PPI dendrimer than that of marketed Ofloxacin tablet formulation
R. K. Narayanswami B.A.B.L. Engine Driver : Story-Telling and Memory in The Grandmother’s Tale, and Selected Stories
Much like the Nambi of this tale, R. K. Narayan has merited his reputation as a marvelous storyteller. Noted for his laser-beam focus on the closely-imagined Malgudi, he has come to be recognized as the Indian novelist, from whose pen many readers expected all the accumulated wisdom of the subcontinent\u27s abiding concern for transcendence. While such guru-ization amused Narayan, it also elicited his quietly sustained argument against procrustean templates by which the west insisted on reading him as typically Indian.
A Non - Singular Cosmological Model with Shear and Rotation
We have investigated a non-static and rotating model of the universe with an
imperfect fluid distribution. It is found that the model is free from
singularity and represents an ever expanding universe with shear and rotation
vanishing for large value of time.Comment: 10 pages, late
Factors Affecting Weld Line Movement in Tailor Welded Blank
Tailor Welded Blanks (TWB) are utilized in automotive industries widely because of their advantage of weight and cost reduction and maintaining required strength and structural integrity. TWB consist of two or more sheet having dissimilar or similar material and thickness; welded together to form a single sheet before forming it to desired shape. Forming of the tailor welded blank is affected by ratio of thickness of blanks, ratio of their strength, etc. mainly due to in-homogeneity of material. In the present work the relative effect of these parameters on weld line movement is studied during deep drawing of TWB using FE simulation using HYPERWORKS. The simulation is validated with results from the literature. Simulations were than performed based on Taguchi orthogonal array followed by the ANOVA analysis to determine the significance of these parameters on forming of TWB
Drug utilization study of off-label drug use in outpatient department of psychiatry: a prospective study at a tertiary care teaching hospital
Background: In the absence of standard psychiatric prescribing information, physician often use drugs in an off-label way. Many studies have been published across the globe reporting different rates of off-label use. There is currently no study based on Indian Drug Formulary.Methods: After taking permission from Institutional Ethics Committee (IEC), a prospective study was conducted among 285 patients attending Psychiatry outpatient department for the period of 4 months. Data related to demographic parameters, diagnosis of psychiatry conditions and drugs details were collected directly from the patient's medical records and entered in Case Record Form (CRF).The off-label drugs were categorized as per National Formulary of India. Multivariate binary logistic regression model was used to determine the predictors of off- label drug prescribing. The data were statistically analyzed using SPSS version 19 and chi-square test.Results: A total of 285 patients (169 males, 116 females) were included in the study with mean age of 36.54±13.91 years. Most of the patients (n=65, 22.8%) were diagnosed as schizophrenic. Out of 285 patients, 133(46.6%) received at least one off-label drug. A total 841 drugs were prescribed out of which 167(19.85%) were off-label. The drug most frequently prescribed as off-label were trihexiphenidyl HCL 29 (10.2%), clozapine 23 (8.1%) and clonazepam 13 (4.6%).Conclusions: Off label drugs used among psychiatry patients was 19.85%. The most frequently used off-label drugs was trihexiphenidyl HCL. The use of off-label drugs in psychiatric patients has been reportedly increasing which warrant national drug regulatory authorities to review and revise safe administration such drugs
Molecular Clock on a Neutral Network
The number of fixed mutations accumulated in an evolving population often
displays a variance that is significantly larger than the mean (the
overdispersed molecular clock). By examining a generic evolutionary process on
a neutral network of high-fitness genotypes, we establish a formalism for
computing all cumulants of the full probability distribution of accumulated
mutations in terms of graph properties of the neutral network, and use the
formalism to prove overdispersion of the molecular clock. We further show that
significant overdispersion arises naturally in evolution when the neutral
network is highly sparse, exhibits large global fluctuations in neutrality, and
small local fluctuations in neutrality. The results are also relevant for
elucidating the topological structure of a neutral network from empirical
measurements of the substitution process.Comment: 10 page
Crotalus atrox venom preconditioning increases plasma fibrinogen and reduces perioperative hemorrhage in a rat model of surgical brain injury.
Perioperative bleeding is a potentially devastating complication in neurosurgical patients, and plasma fibrinogen concentration has been identified as a potential modifiable risk factor for perioperative bleeding. The aim of this study was to evaluate preconditioning with Crotalus atrox venom (Cv-PC) as potential preventive therapy for reducing perioperative hemorrhage in the rodent model of surgical brain injury (SBI). C. atrox venom contains snake venom metalloproteinases that cleave fibrinogen into fibrin split products without inducing clotting. Separately, fibrinogen split products induce fibrinogen production, thereby elevating plasma fibrinogen levels. Thus, the hypothesis was that preconditioning with C. atrox venom will produce fibrinogen spilt products, thereby upregulating fibrinogen levels, ultimately improving perioperative hemostasis during SBI. We observed that Cv-PC SBI animals had significantly reduced intraoperative hemorrhage and postoperative hematoma volumes compared to those of vehicle preconditioned SBI animals. Cv-PC animals were also found to have higher levels of plasma fibrinogen at the time of surgery, with unchanged prothrombin time. Cv-PC studies with fractions of C. atrox venom suggest that snake venom metalloproteinases are largely responsible for the improved hemostasis by Cv-PC. Our findings indicate that Cv-PC increases plasma fibrinogen levels and may provide a promising therapy for reducing perioperative hemorrhage in elective surgeries
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