350 research outputs found

    Superfluid turbulence from quantum Kelvin wave to classical Kolmogorov cascades

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    A novel unitary quantum lattice gas algorithm is used to simulate quantum turbulence of a BEC described by the Gross-Pitaevskii equation on grids up to 5760^3. For the first time, an accurate power law scaling for the quantum Kelvin wave cascade is determined: k^{-3}. The incompressible kinetic energy spectrum exhibits very distinct power law spectra in 3 ranges of k-space: a classical Kolmogorov k^{-5/3} spectrum at scales much greater than the individual quantum vortex cores, and a quantum Kelvin wave cascade spectrum k^{-3} on scales of order the vortex cores. In the semiclassical regime between these two spectra there is a pronounced steeper spectral decay, with non-universal exponent. The Kelvin k^{-3} spectrum is very robust, even on small grids, while the Kolmogorov k^{-5/3} spectrum becomes more and more apparent as the grids increase from 2048^3 grids to 5760^3.Comment: 4 pages, 2 figure

    Transplantation of Skeletal Muscle-Derived Sca-1(+)/PW1(+)/Pax7(-) Interstitial Cells (PICs) Improves Cardiac Function and Attenuates Remodeling in Mice Subjected to Myocardial Infarction

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    We have previously shown that skeletal muscle-derived Sca-1+/PW1+/Pax7− interstitial cells (PICs) are multi-potent and enhance endogenous repair and regeneration. Here, we investigated the regenerative potential of PICs following intramyocardial transplantation in mice subjected to an acute myocardial infarction (MI). MI was induced through the ligation of the left anterior descending coronary artery in 8-week old male C57BL/6 mice. 5 × 105 eGFP-labelled PICs (MI + PICs; n = 7) or PBS (MI-PBS; n = 7) were injected intramyocardially into the border zone. Sham mice (n = 8) were not subjected to MI, or the transplantation of PICs or PBS. BrdU was administered via osmotic mini-pump for 14 days. Echocardiography was performed prior to surgery (baseline), and 1-, 3- and 6-weeks post-MI and PICs transplantation. Mice were sacrificed at 6 weeks post-MI + PICs transplantation, and heart sections were analysed for fibrosis, hypertrophy, engraftment, proliferation, and differentiation of PICs. A significant (p < 0.05) improvement in ejection fraction (EF) and fractional shortening was observed in the MI-PICs group, compared to MI + PBS group at 6-weeks post MI + PICs transplantation. Infarct size/fibrosis of the left ventricle significantly (p < 0.05) decreased in the MI-PICs group (14.0 ± 2.5%), compared to the MI-PBS group (32.8 ± 2.2%). Cardiomyocyte hypertrophy in the border zone significantly (p < 0.05) decreased in the MI-PICs group compared to the MI-PBS group (330.0 ± 28.5 µM2 vs. 543.5 ± 26.6 µm2), as did cardiomyocyte apoptosis (0.6 ± 0.9% MI-PICs vs. 2.8 ± 0.8% MI-PBS). The number of BrdU+ cardiomyocytes was significantly (p < 0.05) increased in the infarct/border zone of the MI-PICs group (7.0 ± 3.3%), compared to the MI-PBS group (1.7 ± 0.5%). The proliferation index (total BrdU+ cells) was significantly increased in the MI-PICs group compared to the MI-PBS group (27.0 ± 3.4% vs. 7.6 ± 1.0%). PICs expressed and secreted pro-survival and reparative growth factors, supporting a paracrine effect of PICs during recovery/remodeling. Skeletal muscle-derived PICs show significant reparative potential, attenuating cardiac remodelling following transplantation into the infarcted myocardium. PICs can be easily sourced from skeletal muscle and therefore show promise as a potential cell candidate for supporting the reparative and regenerative effects of cell therapies

    Transplantation of Skeletal Muscle-Derived Sca-1⁺/PW1⁺/Pax7⁻ Interstitial Cells (PICs) Improves Cardiac Function and Attenuates Remodeling in Mice Subjected to Myocardial Infarction

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    We have previously shown that skeletal muscle-derived Sca-1⁺/PW1⁺/Pax7⁻ interstitial cells (PICs) are multi-potent and enhance endogenous repair and regeneration. Here, we investigated the regenerative potential of PICs following intramyocardial transplantation in mice subjected to an acute myocardial infarction (MI). MI was induced through the ligation of the left anterior descending coronary artery in 8-week old male C57BL/6 mice. 5 × 10⁵ eGFP-labelled PICs (MI + PICs; n = 7) or PBS (MI-PBS; n = 7) were injected intramyocardially into the border zone. Sham mice (n = 8) were not subjected to MI, or the transplantation of PICs or PBS. BrdU was administered via osmotic mini-pump for 14 days. Echocardiography was performed prior to surgery (baseline), and 1-, 3- and 6-weeks post-MI and PICs transplantation. Mice were sacrificed at 6 weeks post-MI + PICs transplantation, and heart sections were analysed for fibrosis, hypertrophy, engraftment, proliferation, and differentiation of PICs. A significant (\u1d631 < 0.05) improvement in ejection fraction (EF) and fractional shortening was observed in the MI-PICs group, compared to MI + PBS group at 6-weeks post MI + PICs transplantation. Infarct size/fibrosis of the left ventricle significantly (\u1d631 < 0.05) decreased in the MI-PICs group (14.0 ± 2.5%), compared to the MI-PBS group (32.8 ± 2.2%). Cardiomyocyte hypertrophy in the border zone significantly (\u1d631 < 0.05) decreased in the MI-PICs group compared to the MI-PBS group (330.0 ± 28.5 µM2 vs. 543.5 ± 26.6 µm2), as did cardiomyocyte apoptosis (0.6 ± 0.9% MI-PICs vs. 2.8 ± 0.8% MI-PBS). The number of BrdU+ cardiomyocytes was significantly (\u1d631 < 0.05) increased in the infarct/border zone of the MI-PICs group (7.0 ± 3.3%), compared to the MI-PBS group (1.7 ± 0.5%). The proliferation index (total BrdU+ cells) was significantly increased in the MI-PICs group compared to the MI-PBS group (27.0 ± 3.4% vs. 7.6 ± 1.0%). PICs expressed and secreted pro-survival and reparative growth factors, supporting a paracrine effect of PICs during recovery/remodeling. Skeletal muscle-derived PICs show significant reparative potential, attenuating cardiac remodelling following transplantation into the infarcted myocardium. PICs can be easily sourced from skeletal muscle and therefore show promise as a potential cell candidate for supporting the reparative and regenerative effects of cell therapie

    Therapeutic hypothermia initiated within 6 hours of birth is associated with reduced brain injury on MR biomarkers in mild hypoxic ischemic encephalopathy: a non-randomised cohort study

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    Objective To examine the effect of therapeutic hypothermia on MR biomarkers and neurodevelopmental outcomes in babies with mild hypoxic-ischaemic encephalopathy (HIE). Design Non-randomised cohort study. Setting Eight tertiary neonatal units in the UK and the USA. Patients 47 babies with mild HIE on NICHD neurological examination performed within 6 hours after birth. Interventions Whole-body cooling for 72 hours (n=32) or usual care (n=15; of these 5 were cooled for <12 hours). Main outcome measures MRI and MR spectroscopy (MRS) within 2 weeks after birth, and a neurodevelopmental outcome assessment at 2 years. Results The baseline characteristics in both groups were similar except for lower 10 min Apgar scores (p=0.02) in the cooled babies. Despite this, the mean (SD) thalamic NAA/Cr (1.4 (0.1) vs 1.6 (0.2); p<0.001) and NAA/Cho (0.67 (0.08) vs 0.89 (0.11); p<0.001) ratios from MRS were significantly higher in the cooled group. Cooled babies had lower white matter injury scores than non-cooled babies (p=0.02). Four (27%) non-cooled babies with mild HIE developed seizures after 6 hours of age, while none of the cooled babies developed seizures (p=0.008). Neurodevelopmental outcomes at 2 years were available in 40 (85%) of the babies. Adverse outcomes were seen in 2 (14.3%) non-cooled babies, and none of the cooled babies (p=0.09). Conclusions Therapeutic hypothermia may have a neuroprotective effect in babies with mild HIE, as demonstrated by improved MRS biomarkers and reduced white matter injury on MRI. This may warrant further evaluation in adequately powered randomised controlled trials

    Влияние адъювантного применения ацетазоламида с неинвазивной вентиляцией легких у больных с тяжелым обострением хронической обструктивной болезни легких

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    The aim of the study was to investigate an efficacy of short-term treatment with acetazolamide (ACET) in patients with acute exacerbation of COPD (AECOPD) and noninvasive ventilation (NIV). Methods. This was a prospective case-control study. The study involved 20 patients. Inclusion criteria were as follows: AECOPD; pH &gt; 7.33; PaCO2 &gt; 48 mmHg; HCO3– &gt; 26 mmol/L; and treatment with NIV. Clinical characteristics, Charlson comorbidity index, APACHE II score, arterial blood gases, and serum electrolytes were recorded before inclusion. Patients were defined as cases when they had received ACET (500 mg per day) for 3 days; they were compared to a matched control group who did not receive ACET. Clinical parameters, arterial blood gases, serum electrolytes, potential adverse effects, and length of hospital stay were monitored daily. Results. No significant differences in baseline characteristics, comorbidities, or concomitant drugs used were found between the groups. Mean duration of hospital stay was significantly shorter in the ACET group (16.2 ± 8.4 days vs 19.1 ± 2.8 days; p = 0.023). An iIntra-group analysis showed a significant improvement in clinical and arterial blood gas parameters in both groups already in the first day of the treatment. In the ACET group, systolic blood pressure (SBP), respiratory rate (RR), and SpO2 significantly improved at day 4 (112.5 ± 4.9 mmHg vs 125 ± 7.1 mmHg (p = 0.001); 15.2 ± 1.1 min–1 vs 17.1 ± 0.9 min–1 (p = 0.001) and 94.7 ± 1.1% vs 92.3 ± 0.8% (p = 0.0001), respectively). There was a significant decrease in PaCO2, pH and HCO3– at day 3 (48 ± 3.8 mmHg vs 52.4 ± 5.3 mmHg (p = 0.0288); 7.374 ± 0.4 vs 7.502 ± 0.17 (p = 0.0015) and 26.4 ± 2.8 mmol/L vs 36.9 ± 4.1 mmol/L (p = 0.00001), respectively) and day 4 (44 ± 2.4 mmHg vs 48.4 ± 4.6 mmHg (p = 0.0115); 7.387 ± 0.02 vs 7.480 ± 0.02 (p = 0.00001) and 24.2 ± 2.1 mmol/L vs 35.6 ± 3.0 mmol/L (p = 0.00001), respectively) in the ACET group. No adverse events were recorded in both groups. Conclusions. ACET adjuvant to NIV appears to be effective and could prevent post-NIV alkalosis occurrence and could reduce the length of hospital stay in patients with AECOPD and mixed metabolic disorders (respiratory acidosis and metabolic alkalosis).При широком использовании неинвазивной вентиляции легких (НВЛ) улучшаются исходы лечения лиц с обострением хронической обструктивной болезни легких (ХОБЛ) и гиперкапнической острой дыхательной недостаточностью (ОДН) за счет снижения потребности в интубации трахеи. При обострении ХОБЛ часто развиваются смешанные нарушения кислотно-щелочного состояния, такие как сочетание респираторного ацидоза и метаболического алкалоза. Не исключено, что коррекция метаболического алкалоза, например, с помощью препарата ацетазоламид (АЦЕТ), также может сыграть положительную роль. Однако клинических данных по оценке применения АЦЕТ при НВЛ у больных с обострением ХОБЛ крайне мало. Целью исследования явилась оценка эффективности краткосрочного лечения АЦЕТ у больных с обострением ХОБЛ и гиперкапнической ОДН, получающих НВЛ. Материалы и методы. В проспективном исследовании «случай–контроль» принимали участие пациенты (n = 20), соответствовавшие критериям включения. Перед включением больных в исследование регистрировались клинические признаки, индекс коморбидности Чарлсона, показатели клинической оценки тяжести состояния по шкале APACHE II, газового состава артериальной крови (ГАК) и уровень электролитов сыворотки крови. Пациенты группы «случай» получали АЦЕТ 500 мг в день в течение 3 дней; их показатели сравнивались с таковыми в контрольной группе, в которой АЦЕТ не применялся. Ежедневно регистрировались и сравнивались клинические параметры, показатели ГАК и уровень электролитов сыворотки крови, потенциальные побочные эффекты и продолжительность пребывания в стационаре. Результаты. Между 2 группами никаких существенных различий в отношении исходных характеристик, сопутствующих заболеваний и приема препаратов не отмечено. Средняя продолжительность пребывания в стационаре была значительно меньше в группе АЦЕТ. По результатам внутригруппового анализа показано значительное улучшение клинических параметров и всех показателей ГАК в обеих группах, начиная с 1-го дня. По результатам межгруппового анализа в группе АЦЕТ отмечены статистически значимые улучшения показателей систолического артериального давления, частоты дыхательных движений и насыщения артериальной крови кислородом на 4-й день; на 3-й день выявлено значительное снижение парциального давления углекислого газа в артериальной крови, pH и содержания бикарбоната в плазме крови. Никаких побочных эффектов в обеих группах не отмечено. Заключение. Адъювантное применение АЦЕТ с НВЛ представляется эффективным, предотвращает алкалоз после НВЛ и способствует сокращению времени пребывания в стационаре при обострении ХОБЛ и смешанных метаболических нарушениях – респираторном ацидозе и метаболическом алкалозе

    Status of Groundnut Research and Production in South Asia

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    South Asia, comprising Bangladesh, Bhutan, India, Myanmar, Nepal, Pakistan, and Sri Lanka, accounts for about 43.4% of the world groundnut (Arachis hypogaea) area (8.6 million ha) and 35.7% of production (8.1 million t). The period coinciding with the Southwest monsoon is the main growing season in the region although the crop is grown in more than one season in India, Myanmar, and Sri Lanka. The low average yields of groundnut in the region result from: raising the crop mostly under rainfed conditions on marginal and submarginal lands with low levels of inputs, use of varieties with long maturity periods, susceptibility of the crop to a plethora of insect pests and diseases, and nonavailability of efficient farm machinery and quality seed. All countries in the region made sustained efforts in the development of improved technology, including development of high-yielding varieties, improved agronomic practices, new and efficient strains of Bradyrhizobium, and efficient and economical plant protection schedules for the control of major insect pests and diseases. When tested in the farmers' fields, the technology indicated much unrealized yield poten- tial. The future crop improvement research in the region aims to concentrate on the areas of crop duration. fresh seed dormancy, resistance/tolerance to major biotic stresses, seed quality and production. and design and development of efficient farm implements and machinery. To realizefull impact of research on groundnut production in the region, it is important to ensure adequate support price and market to the crop. The International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) has contributed substantially towards the development of improved cultivars as well as offering training facilities to accomplish better human resource development in the region

    Region-Specific Microstructure in the Neonatal Ventricles of a Porcine Model

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    © 2018, Biomedical Engineering Society. The neonate transitions from placenta-derived oxygen, to supply from the pulmonary system, moments after birth. This requires a series of structural developments to divert more blood through the right heart and onto the lungs, with the tissue quickly remodelling to the changing ventricular workload. In some cases, however, the heart structure does not fully develop causing poor circulation and inefficient oxygenation, which is associated with an increase in mortality and morbidity. This study focuses on developing an enhanced knowledge of the 1-day old heart, quantifying the region-specific microstructural parameters of the tissue. This will enable more accurate mathematical and computational simulations of the young heart. Hearts were dissected from 12, 1-day-old deceased Yorkshire piglets (mass: 2.1–2.4kg, length: 0.38–0.51m), acquired from a breeding farm. Evans blue dye was used to label the heart equator and to demarcate the left and right ventricle free walls. Two hearts were used for three-dimensional diffusion-tensor magnetic resonance imaging, to quantify the fractional anisotropy (FA). The remaining hearts were used for two-photon excited fluorescence and second-harmonic generation microscopy, to quantify the cardiomyocyte and collagen fibril structures within the anterior and posterior aspects of the right and left ventricles. FA varied significantly across both ventricles, with the greatest in the equatorial region, followed by the base and apex. The FA in each right ventricular region was statistically greater than that in the left. Cardiomyocyte and collagen fibre rotation was greatest in the anterior wall of both ventricles, with less dispersion when compared to the posterior walls. In defining these key parameters, this study provides a valuable insight into the 1-day-old heart that will provide a valuable platform for further investigation the normal and abnormal heart using mathematical and computational models
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