54 research outputs found

    Locality-Aware Qubit Routing for the Grid Architecture

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    Due to the short decohorence time of qubits available in the NISQ-era, it is essential to pack (minimize the size and or the depth of) a logical quantum circuit as efficiently as possible given a sparsely coupled physical architecture. In this work we introduce a locality-aware qubit routing algorithm based on a graph theoretic framework. Our algorithm is designed for the grid and certain \u27grid-like\u27 architectures. We experimentally show the competitiveness of algorithm by comparing it against the approximate token swapping algorithm, which is used as a primitive in many state-of-the-art quantum trans pilers. Our algorithm produces circuits of comparable depth (better on random permutations) while being an order of magnitude faster than a typical implementation of the approximate token swapping algorithm

    Asynchronous Execution of Python Code on Task Based Runtime Systems

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    Despite advancements in the areas of parallel and distributed computing, the complexity of programming on High Performance Computing (HPC) resources has deterred many domain experts, especially in the areas of machine learning and artificial intelligence (AI), from utilizing performance benefits of such systems. Researchers and scientists favor high-productivity languages to avoid the inconvenience of programming in low-level languages and costs of acquiring the necessary skills required for programming at this level. In recent years, Python, with the support of linear algebra libraries like NumPy, has gained popularity despite facing limitations which prevent this code from distributed runs. Here we present a solution which maintains both high level programming abstractions as well as parallel and distributed efficiency. Phylanx, is an asynchronous array processing toolkit which transforms Python and NumPy operations into code which can be executed in parallel on HPC resources by mapping Python and NumPy functions and variables into a dependency tree executed by HPX, a general purpose, parallel, task-based runtime system written in C++. Phylanx additionally provides introspection and visualization capabilities for debugging and performance analysis. We have tested the foundations of our approach by comparing our implementation of widely used machine learning algorithms to accepted NumPy standards

    An Introduction to hpxMP: A Modern OpenMP Implementation Leveraging HPX, An Asynchronous Many-Task System

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    Asynchronous Many-task (AMT) runtime systems have gained increasing acceptance in the HPC community due to the performance improvements offered by fine-grained tasking runtime systems. At the same time, C++ standardization efforts are focused on creating higher-level interfaces able to replace OpenMP or OpenACC in modern C++ codes. These higher level functions have been adopted in standards conforming runtime systems such as HPX, giving users the ability to simply utilize fork-join parallelism in their own codes. Despite innovations in runtime systems and standardization efforts users face enormous challenges porting legacy applications. Not only must users port their own codes, but often users rely on highly optimized libraries such as BLAS and LAPACK which use OpenMP for parallization. Current efforts to create smooth migration paths have struggled with these challenges, especially as the threading systems of AMT libraries often compete with the treading system of OpenMP. To overcome these issues, our team has developed hpxMP, an implementation of the OpenMP standard, which utilizes the underlying AMT system to schedule and manage tasks. This approach leverages the C++ interfaces exposed by HPX and allows users to execute their applications on an AMT system without changing their code. In this work, we compare hpxMP with Clang's OpenMP library with four linear algebra benchmarks of the Blaze C++ library. While hpxMP is often not able to reach the same performance, we demonstrate viability for providing a smooth migration for applications but have to be extended to benefit from a more general task based programming model

    Chemopreventive potential of methanol extract of Dicranopteris linearis leaf on DMBA/croton oil-induced mouse skin carcinogenesis.

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    The present study was carried out to elucidate the chemopreventive potential of methanol extract of Dicranopteris linearis (MEDL) in a two-stage mouse skin carcinogenesis model due to the interrelated inflammation, oxidative stress and tumor promotion pathways. MEDL was prepared in a dose range of 30 to 300 mg/kg body weight. A total of 48 imprinting control region (ICR) female mice (6 to 8 weeks old) were randomly assorted into six groups. To induce skin tumor formation, a single topical application of 7,12-dimethylbenz[a]anthracene (DMBA) at 100 μg/100 μl was applied to the shaved dorsal region of mice, followed by repetitive administration of 1% croton oil, twice weekly for 15 weeks. Topical application of MEDL, 30 min prior to the croton oil application significantly reduced the tumor incidence to 12.5% in 300 mg/kg MEDL-treated group as compared to 87.5% in carcinogen control. The latency period of tumor formation was increased from sixth week in the carcinogen control to ninth and fifteenth weeks in 100 and 300 mg/kg MEDL-treated groups, respectively. The tumor burden of MEDL-treated groups (30, 100, and 300 mg/kg) were significantly lessen (5.67 ± 1.28, 5.00 ± 1.13, and 1.00 ± 0.13), as compared to carcinogen control (7.86 ± 2.37). The tumor volume was also significantly reduced from 9.00 ± 2.27 mm3 in carcinogen control to 3.70 ± 0.96, 2.39 ± 0.54 and 0.26 ± 0.03 mm3 in 30, 100 and 300 mg/kg MEDL-treated groups, respectively. In conclusion, the MEDL exhibited anti-carcinogenic effect in a dose-dependent manner, indicating its chemopreventive potential, which worth further study

    Understanding the role of décollement thickness on the evolution of décollement folds: insights from discrete element models

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    We explored the influence of a variety of geometric and mechanical factors in the evolution of décollement folds above a weak décollement level in a sedimentary sequence. Under an applied overburden pressure, we construct nine discrete element models (DE-models) to test the effects of mechanical stratigraphy, the thickness of the décollement layer, and the number of strong and weak layers within the sedimentary cover sequence. The effects of the aforementioned parameters on the structural style of fold belts and the mechanical evolution of décollement folds that develop during a progressive deformation are what we are searching for. The one-way lateral motion of a rigid, vertical boundary wall was used to shorten the particle assemblage. The models presented in this study were then compared to a natural structure in Iran and demonstrated that the combined effects of mechanical behaviour, the thickness of décollement layer, and the number of strong and weak layers within the sedimentary cover sequence are playing the decisive role in the structural style, kinematic and mechanical evolution of décollement folds

    Understanding the role of décollement thickness on the evolution of décollement folds: insights from discrete element models

    Get PDF
    We explored the influence of a variety of geometric and mechanical factors in the evolution of décollement folds above a weak décollement level in a sedimentary sequence. Under an applied overburden pressure, we construct nine discrete element models (DE-models) to test the effects of mechanical stratigraphy, the thickness of the décollement layer, and the number of strong and weak layers within the sedimentary cover sequence. The effects of the aforementioned parameters on the structural style of fold belts and the mechanical evolution of décollement folds that develop during a progressive deformation are what we are searching for. The one-way lateral motion of a rigid, vertical boundary wall was used to shorten the particle assemblage. The models presented in this study were then compared to a natural structure in Iran and demonstrated that the combined effects of mechanical behaviour, the thickness of décollement layer, and the number of strong and weak layers within the sedimentary cover sequence are playing the decisive role in the structural style, kinematic and mechanical evolution of décollement folds

    Dietary differences between elderly Iranians living in Sweden and Iran a cross-sectional comparative study

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    <p>Abstract</p> <p>Background</p> <p>During the last decades, global migration has increased and many immigrant groups have a higher prevalence than the native born population of several cardiovascular disease risk factors, including poor dietary habits. However, it is uncertain if dietary habits in immigrant populations reflect dietary habits in their country of origin or if the current diet is a consequence of the migration and possible change of dietary habits. The aim of this study was to examine possible dietary differences between elderly Iranians living in Stockholm, Sweden with elderly Iranians living in Tehran, Iran, taking into account sex, age, marital status, and education.</p> <p>Methods</p> <p>Dietary intakes were assessed by semi - quantitative food frequency questionnaire in a cross-sectional study of 121 Iranians living in Stockholm and 52 Iranians living in Tehran, aged 60-80. Differences in dietary habits between the two groups was analysed by bootstrapped regression analyses with 1000 replications.</p> <p>Results</p> <p>Iranians living in Sweden had significantly higher intake of protein, total fat, fiber than Iranians living in Iran, but lower consumption of carbohydrates. The observed differences in intake of macronutrients were reflected in consumed amount of all food items, which were higher among Iranians living in Iran with the exception of bread and grain consumption which was lower.</p> <p>Conclusions</p> <p>There are general differences in dietary habits between Iranians living in Iran and Iranians living in Sweden. Parts of observed differences in dietary habits may reflect a favourable adoption process to the Swedish dietary habits after migration. Meanwhile other differences are point of concern in light of the high prevalence of overweight, among Iranians living in Sweden and can have unfavourable impact in particular in the context of cardiovascular health.</p

    Early-infantile onset epilepsy and developmental delay caused by bi-allelic GAD1 variants.

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    Gamma-aminobutyric acid (GABA) and glutamate are the most abundant amino acid neurotransmitters in the brain. GABA, an inhibitory neurotransmitter, is synthesized by glutamic acid decarboxylase (GAD). Its predominant isoform GAD67, contributes up to ∼90% of base-level GABA in the CNS, and is encoded by the GAD1 gene. Disruption of GAD1 results in an imbalance of inhibitory and excitatory neurotransmitters, and as Gad1-/- mice die neonatally of severe cleft palate, it has not been possible to determine any potential neurological dysfunction. Furthermore, little is known about the consequence of GAD1 disruption in humans. Here we present six affected individuals from six unrelated families, carrying bi-allelic GAD1 variants, presenting with developmental and epileptic encephalopathy, characterized by early-infantile onset epilepsy and hypotonia with additional variable non-CNS manifestations such as skeletal abnormalities, dysmorphic features and cleft palate. Our findings highlight an important role for GAD1 in seizure induction, neuronal and extraneuronal development, and introduce GAD1 as a new gene associated with developmental and epileptic encephalopathy

    Locality-Aware Qubit Routing for the Grid Architecture

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    Due to the short decohorence time of qubits available in the NISQ-era, it is essential to pack (minimize the size and or the depth of) a logical quantum circuit as efficiently as possible given a sparsely coupled physical architecture. In this work we introduce a locality-aware qubit routing algorithm based on a graph theoretic framework. Our algorithm is designed for the grid and certain \u27grid-like\u27 architectures. We experimentally show the competitiveness of algorithm by comparing it against the approximate token swapping algorithm, which is used as a primitive in many state-of-the-art quantum transpilers. Our algorithm produces circuits of comparable depth (better on random permutations) while being an order of magnitude faster than a typical implementation of the approximate token swapping algorithm
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