Sufism

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Hierarchical N-Body problem on graphics processor unit

Galactic simulation is an important cosmological computation, and represents a classical N-body problem suitable for implementation on vector processors. Barnes-Hut algorithm is a hierarchical N-Body method used to simulate such galactic evolution systems. Stream processing architectures expose data locality and concurrency available in multimedia applications. On the other hand, there are numerous compute-intensive scientific or engineering applications that can potentially benefit from such computational and communication models. These applications are traditionally implemented on vector processors. Stream architecture based graphics processor units (GPUs) present a novel computational alternative for efficiently implementing such high-performance applications. Rendering on a stream architecture sustains high performance, while user-programmable modules allow implementing complex algorithms efficiently. GPUs have evolved over the years, from being fixed-function pipelines to user programmable processors. In this thesis, we focus on the implementation of Barnes-Hut algorithm on typical current-generation programmable GPUs. We exploit computation and communication requirements present in Barnes-Hut algorithm to expose their suitability for user-programmable GPUs. Our implementation of the Barnes-Hut algorithm is formulated as a fragment shader targeting the selected GPU. We discuss implementation details, design issues, results, and challenges encountered in programming the fragment shader

Combined measures of oxygenation, haemodynamics and metabolism to understand neural responses in infants

fNIRS is an established research tool used to investigate typical and atypical brain development.Primarily, it provides measures of haemodynamic changes that are used to indirectly infer neural activity. Broadband NIRS provides a more direct marker of neuronal activation through measurement of changes in cytochrome-c-oxidase (CCO). As a cellular measure, CCO can be used as a bridge to improve our understanding of the link between neural and haemodynamic activity or “neurovascular coupling”. Study 1 demonstrated that changes in mitochondrial activity could be measured alongside haemodynamics during functional activation, over the temporal cortex, using a miniature system in four-to-six-month-old infants. In order to investigate the spatial specificity of CCO, its relation to haemodynamics and to build upon our understanding of neurovascular coupling mechanisms, multi-channel broadband NIRS was used alongside EEG in Study 2 where responses were measured over the visual cortex. Study 2 was performed in adults as the development of a concurrent NIRS and EEG protocol was methodologically challenging. Following this, Study 3 extended on experimental paradigms from Studies 1 and 2 to measure changes in metabolic activity and haemodynamics over the temporal and visual cortices, in four-to-seven-month-old infants. This study demonstrated simultaneous broadband NIRS and EEG use in infants for the first time. The results provided evidence of underdeveloped coupling of cerebral blood flow changes and mitochondrial activity in early infancy. Finally, Study 4 extended the protocol to investigate underlying biological mechanisms that may be altered in neurovascular coupling in autism, by studying infants at high familial risk for the disorder. The findings demonstrated that the combined protocol was not only feasible for use to study atypical brain development but also provided preliminary evidence of altered coupling between cerebral energy metabolism and haemodynamics.Taken together, this work illuminates hitherto undocumented evidence of neurovascular coupling during brain development and highlights the potential of using broadband NIRS with EEG for future neurodevelopmental research in typical and atypical populations

Life threatening hyperkalemia following cocaine ingestion: a case report

We present a case of life-threatening hyperkalemia after recreational cocaine ingestion. Acute cocaine-induced rhabdomyolysis led to hyperkalemia, cardiac arrhythmias and cardiogenic shock resulting in multi-organ failure

A Study of Cross-Flow Air Heating via a Multiport Serpentine Microchannel Heat Exchanger

An experimental investigation is performed to determine air side forced convective heat transfer and flow characteristics of wavy fin, serpentine, multi-port slab, crossflow microchannel heat exchanger. Experiments are conducted for 30 different operating conditions in single-phase air-to-ethylene glycol crossflow configuration. These operating conditions (752 \u3c Re_a \u3c 3165, and 23C \u3c T_a,i \u3c 46.5C) yield air side Nusselt number (Nu_a), and Colburn factor (j_a) of up to 8.4 and 0.009 respectively. The Nu_a and j_a obtained in these experiments are generally higher, and friction factor, f_a is generally lower than those found in the literature. Possible explanations for the apparent discrepancies are explored. A thorough uncertainty analysis is performed. Uncertainties in Nu_a, j_a, and friction factor f_a are approximately 4.8%, 5.2%, and 5.8% respectively. A large number of key heat exchanger performance parameters are also investigated in order to develop general correlations suitable for industrial applications and engineers

Fluid choice during perioperative care in children: A survey of present‑day proposing practice by anesthesiologists in a intertiary care hospital

Background: Perioperative fluid therapy in pediatrics has always been a challenging avenue for anesthesiologists. Inappropriate choice of fluid leads to multiple side effects, for instance iatrogenic hyponatremia. Our aim was to observe the current practice of perioperative fluid therapy in pediatric population undergoing surgery in a tertiary care hospital. Methods: After obtaining approval from the Departmental Research Review Committee, a survey form including questions was emailed to anesthesiologists from January 2015 to June 2015. Individual responses were recorded and analyzed. Results: Overall response was 100% from consultant and resident, and total 55 anesthesiologists were participated in this survey. Majority of anesthesiologist have used, 1/2 dextrose saline (52.7%) as fluid of choice in routine intraoperative maintenance, while Hartmann’s solution (41.8%) and normal saline 0.9% (5.5%) were used for rest of the them. The Holliday‑Segar method for maintenance fluid was mentioned by 92.7% of anesthesiologists. Conclusion: The use of hypotonic fluid in perioperative care in pediatric population is still being practiced despite the current guidelines. These results point to a considerable gap between the available evidence and practic