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The role of secondary cyclones and cyclone families for the North Atlantic storm track and clustering over western Europe
Secondary cyclones are those that form in association with a pre‐existing primary cyclone, typically along a trailing cold front. In previously studied cases they have been shown to cause extreme damage across Europe, particularly when multiple cyclones track over the same location in rapid succession (known as cyclone clustering). To determine the dynamical relationship between primary and secondary cyclones over the North Atlantic, a frontal identification algorithm is partnered with a cyclone identification method to objectively identify secondary cyclones in 35 extended winter periods using reanalysis data. Cyclones are grouped into “cyclone families” consisting of a single primary cyclone and one or more secondary cyclones. This paper aims to quantify the differences between secondary and primary cyclones over the North Atlantic, and how cyclone families contribute to episodes of cyclone clustering across western Europe. Secondary cyclones are shown to occur most frequently in the central and eastern North Atlantic, whereas primary cyclones are commonly found over the western North Atlantic. Cyclone families have their strongest presence over the North Atlantic Ocean and contribute more than 50% of cyclones over the main North Atlantic storm track. A final category, solo cyclones, which are not associated with cyclogenesis on any connected fronts, are most commonly identified over continental regions as well as the Mediterranean Sea. Primary cyclones are associated with the development of an environment that is favourable for secondary cyclone growth. Enhanced Rossby wave breaking following primary cyclone development leads to an increase in the upper‐level jet speed and a decrease in low‐level stability. Secondary cyclogenesis commonly occurs in this region of anomalously low stability, close to the European continent. During periods of cyclone clustering, secondary cyclones are responsible for approximately 50% of the total number of cyclones. The increase in jet speed and decrease in static stability initiated by the primary cyclones acts to concentrate the genesis region of secondary cyclones and direct the cyclones that form along a similar track. While there is an increase in the secondary cyclogenesis rate near western Europe during periods of European clustering, the basin‐wide secondary cyclogenesis rate decreases during these periods. Thus the large‐scale environment redistributes secondary cyclones during periods of clustering rather than increasing the total number of secondary cyclones
Multipotent (adult) and pluripotent stem cells for heart regeneration: what are the pros and cons?
Heart failure after myocardial infarction is the leading cause of mortality and morbidity worldwide. Existing medical and interventional therapies can only reduce the loss of cardiomyocytes during myocardial infarction but are unable to replenish the permanent loss of cardiomyocytes after the insult, which contributes to progressive pathological left ventricular remodeling and progressive heart failure. As a result, cell-based therapies using multipotent (adult) stem cells and pluripotent stem cells (embryonic stem cells or induced pluripotent stem cells) have been explored as potential therapeutic approaches to restore cardiac function in heart failure. Nevertheless, the optimal cell type with the best therapeutic efficacy and safety for heart regeneration is still unknown. In this review, the potential pros and cons of different types of multipotent (adult) stem cells and pluripotent stem cells that have been investigated in preclinical and clinical studies are reviewed, and the future perspective of stem cell-based therapy for heart regeneration is discussed. © 2013 BioMed Central Ltd.published_or_final_versio
Studies on the clinical significance of nonesterified and total cholesterol in urine
Gas-liquid chromatographic determinations of nonesterified and total urinary cholesterol were performed in 137 normals, 264 patients with various internal diseases without evidence of neoplasias or diseases of the kidney or urinary tract, 497 patients with malignancies and 236 patients with diseases of the kidney, urinary tract infections or prostatic adenoma with residual urine. A normal range (mean±2 SD) of 0.2–2.2 mg/24 hours nonesterified cholesterol (NEC) and of 0.3–3.0 mg/24 hours total cholesterol (TC) was calculated.
Values of urinary cholesterol excretion were independent of age and sex and did not correlate with cholesterol levels in plasma. Patients with various internal diseases, without evidence of neoplasias nor diseases of the kidney or obstruction of the urinary tract, showed normal urinary cholesterol excretions, as did patients with infections of the urinary tract.
However, elevated urinary cholesterol was found in patients with diseases of the kidney or urinary tract obstruction (prostatic adenoma with residual urine), malignant diseases of the urogenital tract and metastasing carcinoma of the breast. In patients with other malignant diseases urinary cholesterol was usually normal.
Lesions of the urothelial cell membranes are considered to be the most likely cause of urinary cholesterol hyperexcretion. The clinical value of urinary cholesterol determinations as a possible screening test for urogenital carcinomas in unselected populations is limited by lacking specificity, expensive methodology and low prevalence of the mentioned carcinomas, although elevated urinary cholesterol excretions have been observed in early clinical stages of urogenital cancers
Longitudinal study of local authority child and family social workers (wave 1) Findings from a 5 year study of local authority child and family social workers in England.
The longitudinal study investigates recruitment, retention and career progression in local authority child and family social work over 5 years. This is the first of 5 reports.
It provides workforce information for employers and policy makers.
Topics covered in this report include:
•entry routes into local authority child and family social work
•current employment and career history
•workplace wellbeing
•management, supervision and working environment
•job satisfaction
•career progression and future career plan
Adsorptive, Kinetic, Thermodynamic and Inhibitive Properties of Cissus Populnea Stem Extract on the Corrosion of Aluminum in Acid Medium.
The adsorption of Cissus populnea stem extract and its subsequent corrosion inhibition properties on aluminum in 0.5 M HCl solutions have been investigated using weight loss measurements. Inhibition efficiency of the plant extract increased with concentration but decreased with rise in temperature. The adsorption of the inhibitor on the aluminum surface was spontaneous and found to align with Langmuir, Freundlich, Temkin and Flory- Huggins adsorption isotherms. From the values of Ea and ΔG0 obtained, the mechanism of physical adsorption has been proposed. Some thermodynamic and activation parameters were also calculated.Keywords: Adsorption isotherm, Cissus populnea, corrosion, physisorption, thermodynamic
Magnetic resonance peak and nonmagnetic impurities
Nonmagnetic Zn impurities are known to strongly suppress superconductivity.
We review their effects on the spin excitation spectrum in , as investigated by inelastic neutron scattering measurements.Comment: Proceedings of Mato Advanced Research Workshop BLED 2000. To appear
in Nato Science Series: B Physic
Characterization of cortex and white matter injury in a mild hypoxic-ischemic neonatal rat mode by diffusion tensor MR imaging
Animal Studies: Diffusion & Perfusion - Poster presentationWe evaluated hypoxic-ischemic (HI) induced cortex and white matter (WM) damage in a mild HI neonatal rat model at 24h post HI by diffusion tensor MR imaging (DTI) and correlated the DTI indices with histological evaluations. Results showed that significantly decreased FA and ¦Ë// reflected HI induced astrogliosis in the injured cortex, whereas significantly decreased FA with increased ¦Ë¡Í indicated dysmyelination in the WM. Our results demonstrated that early mild HI induced cortex and WM damage could be reflected by DTI indices and these may be potentially useful biomarkers to non-invasively monitor mild HI induced neonatal brain damage.published_or_final_versionThe 17th Scientific Meeting & Exhibition of the International Society of Magnetic Resonance in Medicine (ISMRM), Honolulu, HI., 18-24 April 2009. In Proceedings of ISMRM 17th Scientific Meeting & Exhibition, 2009, p. 359
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