Objectives
Recently metabolic aspects linked to sarcopenic obesity (SO) were investigated. Extant studies involved especially older people from Asian or White-mixed American cohorts. The aims of our ...study were: to explore the prevalence of sarcopenia in Caucasian adult obese subjects using two different indices of sarcopenia, and to investigate the relationship among SO, metabolic syndrome (MS), inflammation, and serum albumin concentrations.
Design
Cross- sectional study.
Subjects/methods
The study was performed from 2011 to 2014 in a hospitalized care setting. Inclusion criteria were: age>18 and <65 years, BMI=30 Kg/m
2
. Fat mass (FM) and fat-free mass (FFM) were assessed by DXA. Appendicular skeletal muscle mass (ASMM) was calculated. Sarcopenia was defined as ASMM/height
2
or ASMM/weight <2SD than the sex-specific mean of a young population. The cutoffs were ASMM/h2<6.54 Kg/m
2
for men and 4.82 Kg/m
2
for women, and ASMM/weight<0.2827 for men and 0.2347 for women. ISI-Matsuda was calculated. MS was diagnosed (NCEP-ATPIII).
Results
727 subjects (age: 45.72±13.56 years, BMI: 37.74±5.82 kg/m
2
) were enrolled. The prevalence of SO was 1.0% or 34.8% in men and 0.6% or 50.1% in women, using ASMM/height2 ratio or ASMM/weight. Subjects with SO based on ASMM/height2 were scarce, only data relying on ASMM/weight were considered. Subjects with SO had higher BMI, waist circumference, FM, and lower FFM and ASMM than nonsarcopenic obese individuals (all p<0.05). ISI-Matsuda was lower and hs-CRP levels were higher in subjects with SO (all p<0.05). MS was more prevalent in subjects with SO than nonsarcopenic obese subjects (47.6% vs 34.3%, p<0.001). ASMM/weight was decreased in subjects with MS (0.2522±0.0410 vs 0.2423±0.0352, p=0.001).
Conclusion
SO is associated with MS and low- grade inflammation in adult Caucasian subjects. Metabolic profile evaluation should be recommended in subjects with SO.
The bare nucleus S(E) factors for the H2(d,p)H3 and H2(d,n)He3 reactions have been measured for the first time via the Trojan Horse Method off the proton in 3He from 1.5 MeV down to 2 keV. This range ...overlaps with the relevant region for Standard Big Bang Nucleosynthesis as well as with the thermal energies of future fusion reactors and deuterium burning in the Pre-Main-Sequence phase of stellar evolution. This is the first pioneering experiment in quasi free regime where the charged spectator is detected. Both the energy dependence and the absolute value of the S(E) factors deviate by more than 15% from available direct data with new S(0) values of 57.4±1.8 MeVb for H3+p and 60.1±1.9 MeVb for He3+n. None of the existing fitting curves is able to provide the correct slope of the new data in the full range, thus calling for a revision of the theoretical description. This has consequences in the calculation of the reaction rates with more than a 25% increase at the temperatures of future fusion reactors.
Abstract
Big Bang Nucleosynthesis (BBN) requires several nuclear physics inputs and nuclear reaction rates. An up-to-date compilation of direct cross sections of is given, being these ones among the ...most uncertain bare-nucleus cross sections. A particular attention is devoted to recently indirectly measured cross-section which give important hints for the nuclear astrophysics community.
In reality, a significant experimental effort has been made over the past 10 years to explore reactions important to the BBN and determine their astrophysical S(E)-factor using the Trojan Horse Method (THM). Then, numerical calculations are made in the relevant temperature ranges for BBN (0.01<T
9
<10) to determine the reaction rates and the relative error for the four reactions of interest. The effects of these values on the calculated primordial abundances and isotopical composition for H, He, and Li were then assessed by using them as input physics for computations of primordial nucleosynthesis. Additionally, recent findings regarding the 7Be(n,
alpha
)4He reaction rate were taken into consideration. These were put up against estimates of primordial abundance derived from observation at various astrophysical places. Additionally, perspectives on reactions will be examined.
The abundance of 26Al carries a special role in astrophysics, since it probes active nucleosynthesis in the Milky Way and constrains the Galactic core-collapse supernovae rate. It is estimated ...through the detection of the 1809 keV γ-line and from the superabundance of 26Mg in comparison with the most abundant Mg isotope (A = 24) in meteorites. For this reason, high precision is necessary also in the investigation of the stable 27Al and 24Mg isotopes. Moreover, these nuclei enter the so-called MgAl cycle, playing an important role in the production of Al and Mg. Recently, high-resolution stellar surveys have shown that the Mg–Al anticorrelation in red-giant stars in globular clusters may hide the existence of multiple stellar populations, and that the relative abundances of Mg isotopes may not be correlated with Al. The common thread running through these astrophysical scenarios is the 27Al(p,α)24Mg reaction, which is the main 27Al destruction channel and directly correlates its abundance with the 24Mg one. Since available reaction rates show large uncertainties owing to the vanishingly small cross section at astrophysical energies, we have applied the Trojan Horse Method to deduce the reaction rate with no need of extrapolation. The indirect measurement made it possible to assess the contribution of the 84 keV resonance and to lower upper limits on the strength of nearby resonances. In intermediate-mass AGB stars experiencing hot bottom burning, a sizeable increase in surface aluminum abundance is observed at the lowest masses, while 24Mg is essentially unaffected by the change in the reaction rate.
Organic micro-contaminants (OMCs) enter in freshwaters and interact with other contaminants such as carbon nanoparticles, becoming a problem of unknown consequences for river ecosystems. Carbon ...nanoparticles (as fullerenes C
) are good adsorbents of organic contaminants and their interaction can potentially affect their toxicity to river biofilms. We tested the C
interactions with selected OMCs and their effects on river biofilms in different short-term experiments. In these, river biofilms were exposed to C
and three OMCs (triclosan, diuron, or venlafaxine) and their respective mixtures with fullerenes (C
+ each OMC). The effects were evaluated on structural, molecular, and functional descriptors of river biofilms. Our results showed that C
did not cause toxic effects in river biofilms, whereas diuron and triclosan significantly affected the heterotrophic and phototrophic components of biofilms and venlafaxine affected only the phototrophic component. The joint exposure of C
with venlafaxine was not producing differences with respect to the former response of the toxicant, but the overall response was antagonistic (i.e., decreased toxicity) with diuron, and synergistic (i.e., increased toxicity) with triclosan. We suggest that differences in the toxic responses could be related to the respective molecular structure of each OMC, to the concentration proportion between OMC and C
and to the possible competition between C
pollutants on blocking the receptors of the biological cell membranes. We conclude that the presence of C
at low concentrations modified the toxicity of OMC to river biofilms. These interactions should therefore be considered when predicting toxicity of OMC in river ecosystems.
A single crystal diamond detector was exposed to quasi mono-energetic neutron fields in the energy range from 5 to 20.5
MeV. Response functions of such a detector were measured for the first time for ...neutron energies above 14
MeV. The pulse height spectra showed sharp peaks at specific energies. These peaks result from neutron induced charged particle reactions occurring in carbon at different neutron energies. The centroid of the peaks due to the
12C(n,α)
9Be reaction permitted, by means of the reaction
Q-values, to point out a good linearity of the detector response versus neutron energy and a good intrinsic energy resolution of about 56
keV at full width at half maximum. The results reveal that single crystal diamond detectors are good candidates as high resolution fast neutron spectrometers for nuclear fusion applications and for systematic studies of beam and target characteristics for neutron-producing reactions.
The Trojan Horse Method (THM) lays its foundations on the cluster structure of light nuclei which are usually used as “Trojan horses”. Many of them were successfully employed in the last decades to ...shed light to numerous astrophysical problems. Cluster structure and dynamics also suggest a series of tests which may be performed in order to strengthen the basis of the method. Among them pole invariance was investigated for three different situations. In fact, the cross sections for the
6
Li(d,
α
)
4
He,
2
H(d,p)
3
H and
7
Li(p,
α
)
4
He binary reactions were measured for several break-up schemes and analyzed within the framework of the Plane Wave Impulse Approximation (PWIA). The indirect results extracted by using different Trojan Horse nuclei (e.g.
2
H,
3
He,
6
Li) were compared with each other as well as with direct measurements of the corresponding astrophysical reactions. The very good agreement obtained confirms the applicability of the pole approximation and of the pole invariance method, namely the independence of binary indirect cross section on the chosen Trojan Horse nucleus, at least for the cases investigated. Moreover, we can verify that the effect of using a charged or a neutral particle as a spectator implies negligible corrections consistent with the experimental errors. In addition, the dynamics of clusters inside the Trojan Horse nucleus and their fingerprints on the measured momentum distribution play a key role for THM applications. In this article we will therefore discuss also these assertions studied in different systems(
2
H,
3
He,
6
Li,
9
Be,
14
N) and in particular for the deuteron case the relative impact of
s
and
d
waves in the momentum distribution will also be examined.
Carbon burning powers scenarios that influence the fate of stars, such as the late evolutionary stages of massive stars 1 (exceeding eight solar masses) and superbursts from accreting neutron ...stars2,3. It proceeds through the 12C + 12C fusion reactions that produce an alpha particle and neon-20 or a proton and sodium-23-that is, 12C(12C, α)20Ne and 12C(12C, p)23Na-at temperatures greater than 0.4 × 109 kelvin, corresponding to astrophysical energies exceeding a megaelectronvolt, at which such nuclear reactions are more likely to occur in stars. The cross-sections 4 for those carbon fusion reactions (probabilities that are required to calculate the rate of the reactions) have hitherto not been measured at the Gamow peaks 4 below 2 megaelectronvolts because of exponential suppression arising from the Coulomb barrier. The reference rate 5 at temperatures below 1.2 × 109 kelvin relies on extrapolations that ignore the effects of possible low-lying resonances. Here we report the measurement of the 12C(12C, α0,1)20Ne and 12C(12C, p0,1)23Na reaction rates (where the subscripts 0 and 1 stand for the ground and first excited states of 20Ne and 23Na, respectively) at centre-of-mass energies from 2.7 to 0.8 megaelectronvolts using the Trojan Horse method6,7 and the deuteron in 14N. The cross-sections deduced exhibit several resonances that are responsible for very large increases of the reaction rate at relevant temperatures. In particular, around 5 × 108 kelvin, the reaction rate is boosted to more than 25 times larger than the reference value 5 . This finding may have implications such as lowering the temperatures and densities 8 required for the ignition of carbon burning in massive stars and decreasing the superburst ignition depth in accreting neutron stars to reconcile observations with theoretical models 3 .
Loss of the sense of taste is common among older people. Morbidities and polypharmacy may contribute to the age-related decline in gustatory function. The aims of the present study were to ...investigate taste perception in elderly hospitalized patients by comparing their taste recognition thresholds with those of healthy, free-living elderly individuals and to identify potential determinants of taste loss.
The participants in this observational study were 55 elderly patients hospitalized in the acute geriatric section of the Department of Medical and Surgical Sciences at Padova University and 41 free-living individuals aged older than 65 years, randomly recruited from elderly people attending mild fitness programs at public gymnasiums in Padova. Data were collected on nutrition, health, cognitive, and functional status for all participants. Gustatory capabilities were assessed using aqueous solutions of sucrose, sodium chloride, citric acid, and quinine hydrochloride (representing sweet, salty, sour, and bitter stimuli, respectively), and taste recognition thresholds were measured in both groups.
In comparison with the free-living elderly subjects, those in hospital were significantly less able to recognize the taste of citric acid (P < 0.05). Low citric acid sensitivity was independently associated with advanced age (≥75 years; odds ratio OR 3.01, 95% confidence interval CI 1.01-9.82), polypharmacy (number of prescribed drugs ≥ 4; OR 2.74, 95% CI 1.01-7.72), and poor nutritional status (as assessed by Mini Nutritional Assessment score < 23.5; OR 5.08, 95% CI 1.76-14.6).
Because gustatory impairment may reduce a person's appetite and lead to inadequate dietary intake, compensatory nutritional measures, such as the use of flavor-enhanced foods, should be strongly encouraged, particularly in the hospital setting.
7Be destruction channels are currently a matter of study because of their influence on the 7Li cosmological abundances. Here, we determine the cross section of the (n, ) reaction by using Trojan ...Horse experimental data for the 7Li(p, )4He reaction and correcting for Coulomb effects. The deduced 7Be(n, )4He data overlap with the Big Bang nucleosynthesis energies and the deduced reaction rate allows us to evaluate the corresponding cosmological implications.
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