1,553 research outputs found
An importance sampling algorithm for generating exact eigenstates of the nuclear Hamiltonian
We endow a recently devised algorithm for generating exact eigensolutions of
large matrices with an importance sampling, which is in control of the extent
and accuracy of the truncation of their dimensions. We made several tests on
typical nuclei using a correlated basis obtained from partitioning the shell
model space. The sampling so implemented allows not only for a substantial
reduction of the shell model space but also for an extrapolation to exact
eigenvalues and E2 strengths.Comment: A compressed file composed of a text in latex of 19 pages and 9
figures in p
Ecology and management of moose in northern New England
This study examined three facets of moose ecology in northern New England: impact of moose browsing on forest regeneration, physical characteristics of harvested bull moose, and winter habitat use. Forest regeneration was not considered a major problem in northern Vermont based on stocking levels of commercial tree species. Increasing dominance of softwood species coupled with suppressed growth of hardwoods suggests possible local shifts in composition. Bull moose in Maine had stable body weight and antler spread, and selective harvest of trophy bulls was not apparent over 30 years. Winter locations from aerial surveys indicated that moose preferentially used deciduous/mixed forest proximate to cuts; wetlands and conifer stands were used less. Good physical condition of harvested moose and similarities in habitat use at multiple scales indicates that commercial timber harvesting provides long-term, high quality moose habitat in northern Maine
Elevated hemoglobin glycation index identify non-diabetic individuals at increased risk of kidney dysfunction
Hemoglobin glycation index (HGI), calculated as the difference between the observed value of HbA1 and the predicted HbA1c based on plasma glucose concentration, is a measure of the individual tendency toward non-enzymatic hemoglobin glycation which has been found to be positively associated with nephropathy in subjects with diabetes. In this cross-sectional study we aimed to evaluate whether higher HGI levels are associated with impaired kidney function also among nondiabetic individuals. The study group comprised 1505 White nondiabetic individuals stratified in quartiles according to HGI levels. Estimated glomerular filtration rate (eGFR) was calculated by using the MDRD equation. Individuals in the intermediate and high HGI groups exhibited a worse metabolic phenotype with increased levels of visceral obesity, total cholesterol, triglycerides, inflammatory biomarkers such as hsCRP and white blood cells count and lower values of HDL and insulin sensitivity assessed by Matsuda index in comparison to the lowest quartile of HGI. Subjects in the intermediate and high HGI groups displayed a graded decrease of eGFR levels in comparison with the lowest quartile of HGI. In a logistic regression analysis individuals in the highest quartile of HGI exhibited a significantly 3.6-fold increased risk of having chronic kidney disease (95% CI: 1.13-11.24, P = 0.03) and a significantly 1.6-fold increased risk of having a mildly reduced kidney function (95% CI: 1.19-2.28, P = 0.003) in comparison to individuals in the lowest HGI group. In conclusion HGI may be a useful tool to identify nondiabetic individuals with an increased risk of having kidney dysfunction
Elevated hemoglobin glycation index identify non-diabetic individuals at increased risk of kidney dysfunction
Hemoglobin glycation index (HGI), calculated as the difference between the observed value of HbA1 and the predicted HbA1c based on plasma glucose concentration, is a measure of the individual tendency toward non-enzymatic hemoglobin glycation which has been found to be positively associated with nephropathy in subjects with diabetes. In this cross-sectional study we aimed to evaluate whether higher HGI levels are associated with impaired kidney function also among nondiabetic individuals. The study group comprised 1505 White nondiabetic individuals stratified in quartiles according to HGI levels. Estimated glomerular filtration rate (eGFR) was calculated by using the MDRD equation. Individuals in the intermediate and high HGI groups exhibited a worse metabolic phenotype with increased levels of visceral obesity, total cholesterol, triglycerides, inflammatory biomarkers such as hsCRP and white blood cells count and lower values of HDL and insulin sensitivity assessed by Matsuda index in comparison to the lowest quartile of HGI. Subjects in the intermediate and high HGI groups displayed a graded decrease of eGFR levels in comparison with the lowest quartile of HGI. In a logistic regression analysis individuals in the highest quartile of HGI exhibited a significantly 3.6-fold increased risk of having chronic kidney disease (95% CI: 1.13-11.24, P = 0.03) and a significantly 1.6-fold increased risk of having a mildly reduced kidney function (95% CI: 1.19-2.28, P = 0.003) in comparison to individuals in the lowest HGI group. In conclusion HGI may be a useful tool to identify nondiabetic individuals with an increased risk of having kidney dysfunction
Insulin-like growth factor-1 is a negative modulator of glucagon secretion
Glucagon secretion involves a combination of paracrine, autocrine, hormonal, and autonomic neural mechanisms. Type 2 diabetes often presents impaired glucagon suppression by insulin and glucose. Insulin-like growth factor-I (IGF-1) has elevated homology with insulin, and regulates pancreatic β-cells insulin secretion. Insulin and IGF-1 receptors share considerable structure homology and function. We hypothesized the existence of a mechanism linking the inhibition of α-cells glucagon secretion to IGF-1. Herein, we evaluated the association between plasma IGF-1 and glucagon levels in 116 nondiabetic adults. After adjusting for age gender and BMI, fasting glucagon levels were positively correlated with 2-h post-load glycaemia, HOMA index and fasting insulin, and were negatively correlated with IGF-1 levels. In a multivariable regression, the variables independently associated to fasting glucagon were circulating IGF-1 levels, HOMA index and BMI, explaining 20.7% variation. To unravel the molecular mechanisms beneath IGF-1 and glucagon association, we investigated whether IGF-1 directly modulates glucagon expression and secretion in an in vitro model of α-cells. Our data showed that IGF-1 inhibits the ability of low glucose concentration to stimulate glucagon expression and secretion via activation of the phosphatidylinositol-3-kinase/Akt/FoxO1 pathway. Collectively, our results suggest a new regulatory role of IGF-1 on α-cells biological function
Structure of exotic nuclei around double shell closures
In this paper, we first give a brief review of the theoretical framework for
microscopic shell-model calculations starting from the free nucleon-nucleon
potential. In this context, we discuss the use of the low-momentum
nucleon-nucleon interaction V-low-k in the derivation of the shell-model
effective interaction and emphasize its practical value as an alternative to
the Brueckner G-matrix method. Then, we present some results of our current
study of exotic nuclei around doubly magic 132Sn, which have been obtained
starting from the CD-Bonn potential renormalized by use of the V-low-k
approach. Attention is focused on the nuclei 134Te, 134Sn, and 136Te, in
particular on the latter which is a direct source of information on the
proton-neutron effective interaction in the 132Sn region. Comparison shows that
our results are in very good agreement with the available experimental data.Comment: 8 pages, 3 figures, to be published in Prog. Part. Nucl. Phy
Reciprocal Association of Plasma IGF-1 and Interleukin-6 Levels With Cardiometabolic Risk Factors in Nondiabetic Subjects
OBJECTIVE—To examine the relationship between plasma IGF-1 and interleukin-6 (IL-6) levels in Caucasian nondiabetic subjects and evaluate the association of IGF-1 and IL-6 with the cardiometabolic risk factors characterizing metabolic syndrome (MetS)
Serum IgG2 levels are specifically associated with whole-body insulin-mediated glucose disposal in non-diabetic offspring of type 2 diabetic individuals. a cross-sectional study
.Preclinical studies suggested that IgG2c isotype may specifically impair skeletal muscle insulin
sensitivity in mice. In this study we investigated the association between serum levels of the four IgG
subclasses and insulin sensitivity in non-diabetic individuals. Total IgG, IgG1, IgG2, IgG3 and IgG4
levels were measured in 262 subjects. Whole-body insulin sensitivity was assessed by euglycemic
hyperinsulinemic clamp. IgG2 levels were positively correlated with BMI, waist circumference, 2-h postload
glucose levels and complement C3. Serum IgG2, but not IgG1, IgG3 and IgG4 levels were negatively
correlated with whole-body insulin sensitivity (r = −0.17; P = 0.003) and muscle insulin sensitivity index
(r = −0.16; P = 0.03) after adjustment for age and gender. No significant correlation was found between
IgG2 levels and hepatic insulin resistance assessed by HOMA-IR and liver IR index. In a multivariable
regression analysis including variables known to affect insulin sensitivity such as age, gender, BMI,
smoking, lipids, inflammatory markers, fasting and 2-h post-load glucose levels, IgG2 levels were
independently associated with insulin-stimulated glucose disposal (β = −0.115, 95% CI: −0.541 to
−0.024; P = 0.03). These data demonstrate the independent association between higher levels of IgG2
and decreased whole-body insulin sensitivity, thus confirming in humans the animal-based evidence
indicating the pathogenic role of IgG2 in insulin resistance
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