Computer Aided Design of the Pipelined Interconnect Free Logic

The Pipelined Interconnect Free (PIF) logic design methodology has the potential to eliminate several problems that are faced by the modern technology digital designers. It is very easy to model and it gives an exact idea of the circuit layout during design phase only as it uses only one type of gate and does not have any global interconnects. The thesis discusses the PIF logic circuits, their applications and performance. It discusses the full implementation of a PIF one bit full adder starting from schematic to layout stage. It discusses the issues related to the implementation of larger PIF logic circuit like a multiplier. The thesis also explains the design of an automated CAD tool which will have an interface for schematic entry of the PIF logic circuit and will generate the physical layout for the circuit in the form of a CIF file. The tool functioning is demonstrated by the implementation of a one bit PIF full adder and 2X2 multiplier

Design and development of a compact x-ray tube for stationary CT architecture

Multisource architectures enable sweeping one or more x-ray beams across the imaging field-of-view faster than physically moving a single x-ray source and/or a detector. Hence, these architectures are attractive for the applications in which temporal resolution plays an important role, for example, cardiac computed tomography (CT) or real-time CT. One of the recent developments in multisource architectures for CT imaging is stationary CT architecture, whereby two separate stationary arrays -- one for x-ray sources and one for detectors -- are utilized to sweep one or more x-ray beams along the gantry and acquire 360 degree projections. To have a stationary CT architecture and still acquire enough number of projections for a successful CT reconstruction, an array of closely spaced and individually addressable x-ray sources that are compact in size and are capable of producing x-ray pulses at a high frequency is required. This work is a part of a research continuum toward developing a compact x-ray tube potentially to be used in the said stationary CT architecture. The central hypothesis of the research conducted is that, a field emission (FE) based cold cathode and transmission type anode allow the size of an x-ray tube to be reduced, and still generate a required x-ray pulse. Specifically, this work entails the design of an electrostatic lens for electron focusing in a compact x-ray tube and the initial experimental studies of a prototype compact x-ray tube. Using particle-in-cell code, OOPIC PRO, electron field emission from CNT cathode and electron focusing by three types of electrostatic lenses--Single lens, Double lens, and Einzel lens--were simulated, compared, and studied for anode voltages of 30 kV p to 140 kV p. The first-generation prototype compact x-ray tube was developed and studied. The initial studies conducted to understand the performance of the prototype and its control parameters. After further optimization of size and testing, this compact x-ray tube design holds a potential to be used in a stationary CT architecture for improved temporal resolution --Abstract, page iv

The JetCurry Code. I. Reconstructing Three-Dimensional Jet Geometry from Two-Dimensional images

We present a reconstruction of jet geometry models using numerical methods based on a Markov ChainMonte Carlo (MCMC) and limited memory Broyden-Fletcher-Goldfarb-Shanno (BFGS) optimized algorithm. Our aim is to model the three-dimensional geometry of an AGN jet using observations, which are inherently two-dimensional. Many AGN jets display complex hotspots and bends over the kiloparsec scales. The structure of these bends in the jets frame may be quite different than what we see in the sky frame, transformed by our particular viewing geometry. The knowledge of the intrinsic structure will be helpful in understanding the appearance of the magnetic field and hence emission and particle acceleration processes over the length of the jet. We present the method used, as well as a case study based on a region of the M87 jet.Comment: Submitted to ApJ on Feb 01, 201

Formulation and characterization of self emulsifing pellets of carvedilol

O propósito do presente estudo foi desenvolver um sistema líquido de liberação de fármacos auto emulsificante e, então, na forma de pélete, que poderia resultar em aprimoramento da solubilidade, da dissolução e permeabilidade do fármaco carvedilol, pouco solúvel em água. Os péletes foram preparados utilizando-se a técnica de extrusão-esferonização, incorporando líquido SEDDS (carvedilol, capmul MCM EP, Cremofor EL, Tween 20, propileno glicol), adsorventes (e crospovidona), celulose microcristallina e ligante (povidona K-30). O diagrama de fase ternário foi construído para identificar as misturas diferentes de óleo-tensoativo-co-tensoativo, de acordo com a proporção em cada ponto delas. Os péletes CAR-SEDDS mostraram redispersão mais rápida, com tamanho de gota da microemulsão reconstituída de 160,47 nm, que se mostrou quase inalterada após a solidificação. A análise por SEM confirmou a aparência esférica dos péletes sólidos. Análise por DSC e XRD confirmou que não havia carvedilol cristalino nos péletes. Estes foram, então capazes de transferir os compostos lipofílicos para a fase aquosa, aumentando, significativamente, sua liberação em relação ao fármaco puro.The purpose of present study was aimed at developing self emulsifying drug delivery system in liquid and then in pellet form that would result in improved solubility, dissolution and permeability of the poorly water soluble drug carvedilol. Pellets were prepared using extrusion-spheronization technique incorporating liquid SEDDS (carvedilol, capmul MCM EP, cremophore EL, tween 20, propylene glycol), adsorbents ( and crospovidone), microcrystalline cellulose and binder (povidone K-30). Ternary phase diagram was constructed to identify different oil-surfactant-cosurfactant mixtures according to the proportion of each point in it. The optimal CAR-SEDDS pellets showed a quicker redispersion with a droplet size of the reconstituted microemulsion being 160.47 nm, which was almost unchanged after solidification. SEM analysis confirmed good spherical appearance of solid pellets; DSC and XRD analysis confirmed that there was no crystalline carvedilol in the pellets. Pellets were then capable of transferring lipophilic compounds into the aqueous phase and significantly enhancing its release with respect to pure drug

Investigating the robustness of a learning-based method for quantitative phase retrieval from propagation-based x-ray phase contrast measurements under laboratory conditions

Quantitative phase retrieval (QPR) in propagation-based x-ray phase contrast imaging of heterogeneous and structurally complicated objects is challenging under laboratory conditions due to partial spatial coherence and polychromaticity. A learning-based method (LBM) provides a non-linear approach to this problem while not being constrained by restrictive assumptions about object properties and beam coherence. In this work, a LBM was assessed for its applicability under practical scenarios by evaluating its robustness and generalizability under typical experimental variations. Towards this end, an end-to-end LBM was employed for QPR under laboratory conditions and its robustness was investigated across various system and object conditions. The robustness of the method was tested via varying propagation distances and its generalizability with respect to object structure and experimental data was also tested. Although the LBM was stable under the studied variations, its successful deployment was found to be affected by choices pertaining to data pre-processing, network training considerations and system modeling. To our knowledge, we demonstrated for the first time, the potential applicability of an end-to-end learning-based quantitative phase retrieval method, trained on simulated data, to experimental propagation-based x-ray phase contrast measurements acquired under laboratory conditions. We considered conditions of polychromaticity, partial spatial coherence, and high noise levels, typical to laboratory conditions. This work further explored the robustness of this method to practical variations in propagation distances and object structure with the goal of assessing its potential for experimental use. Such an exploration of any LBM (irrespective of its network architecture) before practical deployment provides an understanding of its potential behavior under experimental settings.Comment: Under review as a journal submission. Early version with partial results has been accepted for poster presentation at SPIE-MI 202

Study of Orthopedic Morbidities among Postmenopausal Women in a Medical College Hospital in Rural Area of Western Maharashtra, India

Introduction: It is estimated that a total of 130 million Indian women are expected to live beyond menopause by 2015. Health of postmenopausal women is of growing concern because of increased longevity and various morbidities associated with old age. Objectives: 1) To assess various orthopedic problems among postmenopausal women in rural area. 2) To estimate magnitude of common orthopedic problems and associated sociodemographic factors. Methodology: A cross-sectional study was conducted at the medical college hospital in rural area of Western Maharashtra on 500 postmenopausal women availing healthcare in a medical college hospital. Data was collected with the help of predesigned questionnaire by interview technique and with the help of case records available from orthopedic department. Results: Backache (62%) and osteoarthritis (51.6%) were common orthopedic problems. Osteoarthritis was significantly associated with obesity

Preparation and characterization of transparent conducting ZnTe : Cu back contact interface layer for CdS/CdTe solar cell for photoelectrochemical application

FSEC Photovoltaic Materials Laboratory has developed a photoelectrochemical (PEC) cell using multiple band gap tandem of thin-film photovoltaic (PV) cells and a photocatalyst for hydrogen production by water splitting. CdS/CdTe solar cell, a promising candidate for low-cost, thin-film PV cell, is used as one of the thin-film solar cells in a PEC cell. The back contact has been developed for a CdS/CdTe solar cell which involves the deposition of a primary p-type ZnTe:Cu back contact interface layer followed by the deposition of transparent and conducting ZnO:AI and Ni-Al outer metallization layer. This article presents preparation and characterization of ZnTe:Cu back contact interface layer deposited by hot wall vacuum evaporation (HWVE) technique. HWVE technique has produced highly stoichiometric ZnTe:Cu thin films with cubic phase having {111} texture orientation and produced better transparency in the near infrared region on a glass substrate. (c) 2006 American Vacuum Society

Determinants of Recurrent Diarrhoea among Children

BackgroundAbout 2 million episodes of diarrhoea occur each year in India. Of the 6.6 million deaths among children aged 28 days to 5 year; deaths from diarrhoea are estimated to account for 1.87 million. An average Indian child less than 5 years of age can have 2-3 episodes of diarrhoea.  Mother's literacy, family income, feeding practices, environmental conditions are important determinants of the common childhood infection like diarrhoea. The present study was undertaken to study these important determinants of recurrent diarrhoea among children under five in a rural area of western Maharashtra, India.Method  A cross-sectional study was conducted in six randomly selected villages of Ahmednagar district in western Maharashtra, India. Three villages from two primary health centres and 652 children under five from these villages were chosen by a simple random sampling technique (every fifth child enrolled in Anganwadi). House-to-house survey was done and data was collected by interviewing the mothers of these children. Nutritional status was assessed by measuring the weight and mid-arm circumference of the child. Statistical analysis was done with Microsoft Excel and StatistiXL 1.8 using percentage, proportions and chi-square test wherever applicable.ResultsThe prevalence of recurrent diarrhoea was 9.81%. Recurrent diarrhoea was more common in the age group of 13 - 24 months (29.6%) and 25 – 36 months (23.4%) and children belonging to lower socioeconomic class (64%). Malnutrition was significantly associated with recurrent diarrhoea and 21% of malnourished children had the same. Recurrent diarrhoea was significantly more common (39.1%) among children with introduction of top-up feeds before four to six months.ConclusionLow socioeconomic status, bad sanitary practices, nutritional status and weaning practices significantly influence the prevalence of recurrent diarrhoea