We construct a supergravity model whose scalar degrees of freedom arise from a chiral superfield and are solely a scalaron and an axion that is very heavy during the inflationary phase. The model ...includes a second chiral superfield X, which is subject however to the constraint X2=0 so that it describes only a Volkov–Akulov goldstino and an auxiliary field. We also construct the dual higher-derivative model, which rests on a chiral scalar curvature superfield R subject to the constraint R2=0, where the goldstino dual arises from the gauge-invariant gravitino field strength as γmnDmψn. The final bosonic action is an R+R2 theory involving an axial vector Am that only propagates a physical pseudoscalar mode.
Properties of nilpotent supergravity Dudas, E.; Ferrara, S.; Kehagias, A. ...
The journal of high energy physics,
09/2015, Letnik:
2015, Številka:
9
Journal Article
Recenzirano
Odprti dostop
A
bstract
We construct supergravity models where the goldstino multiplet has a gravitational origin, being dual to the chiral curvature superfield. Supersymmetry is nonlinearly realized due to a ...nilpotent constraint, while the goldstino arises from
γ
-traces of the gauge-invariant gravitino field strength. After duality transformations one recovers, as expected, the standard Volkov-Akulov Lagrangian coupled to Supergravity, but the gravitational origin of the goldstino multiplet restricts the available types of matter couplings. We also construct explicitly some inflationary models of this type, which contain both the inflaton and the nilpotent superfield.
A scale invariant goldstino theory coupled to supergravity is obtained as a standard supergravity dual of a rigidly scale-invariant higher-curvature supergravity with a nilpotent chiral scalar ...curvature. The bosonic part of this theory describes a massless scalaron and a massive axion in a de Sitter Universe.
To present best-practice recommendations for the prevention, recognition, and treatment of exertional heat illnesses (EHIs) and to describe the relevant physiology of thermoregulation.
Certified ...athletic trainers recognize and treat athletes with EHIs, often in high-risk environments. Although the proper recognition and successful treatment strategies are well documented, EHIs continue to plague athletes, and exertional heat stroke remains one of the leading causes of sudden death during sport. The recommendations presented in this document provide athletic trainers and allied health providers with an integrated scientific and clinically applicable approach to the prevention, recognition, treatment, and return-to-activity guidelines for EHIs. These recommendations are given so that proper recognition and treatment can be accomplished in order to maximize the safety and performance of athletes.
Athletic trainers and other allied health care professionals should use these recommendations to establish onsite emergency action plans for their venues and athletes. The primary goal of athlete safety is addressed through the appropriate prevention strategies, proper recognition tactics, and effective treatment plans for EHIs. Athletic trainers and other allied health care professionals must be properly educated and prepared to respond in an expedient manner to alleviate symptoms and minimize the morbidity and mortality associated with these illnesses.
The imaginary Starobinsky model Ferrara, S.; Kehagias, A.; Riotto, A.
Fortschritte der Physik,
July 2014, Letnik:
62, Številka:
7
Journal Article
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Odprti dostop
The recent detection by the BICEP2 collaboration of a high level of tensor modes seems to exclude the Starobinsky model of inflation. In this paper we show that this conclusion can be avoided: one ...can embed the Starobinsky model in supergravity and identify the inflaton field with the imaginary (instead of the real) part of the chiral scalaron multiplet in its formulation. Once coupled to matter, the Starobinsky model may then become the chaotic quadratic model with shift symmetry during inflation and is in good agreement with the current data.
The recent detection of a high level of tensor modes seems to exclude the Starobinsky model of inflation. In this paper it is shown that this conclusion can be avoided: one can embed the Starobinsky model in supergravity and identify the inflaton field with the imaginary (instead of the real) part of the chiral scalaron multiplet in its formulation. Once coupled to matter, the Starobinsky model may then become the chaotic quadratic model with shift symmetry during inflation and is in good agreement with the current data.
A
bstract
We identify a cubic holomorphic constraint that subtends the total breaking of
N
= 2 supersymmetry in a vector multiplet and exhibit its microscopic origin. The new constraint leaves ...behind, at low energies, a vector and the two goldstini, in a non-linear Lagrangian that generalizes the
N
= 2 Volkov-Akulov model.
We elaborate on how to build, in a systematic fashion, two-field Abelian extensions of the Born–Infeld Lagrangian. These models realize the non-trivial duality groups that are allowed in this case, ...namely U(2), SU(2) and U(1)×U(1). For each class, we also construct an explicit example. They all involve an overall square root and reduce to the Born–Infeld model if the two fields are identified, but differ in quartic and higher interactions. The U(1)×U(1) and SU(2) examples recover some recent results obtained with different techniques, and we show that the U(1)×U(1) model admits an N=1 supersymmetric completion. The U(2) example includes some unusual terms that are not analytic at the origin of field space.
Interventions including physical exercise may help improve the outcomes of late-life major depression, but few studies are available.
To investigate whether augmenting sertraline therapy with ...physical exercise leads to better outcomes of late-life major depression.
Primary care patients (465 years) with major depression were randomised to 24 weeks of higher-intensity, progressive aerobic exercise plus sertraline (S+PAE), lower-intensity, non-progressive exercise plus sertraline (S+NPE) and sertraline alone. The primary outcome was remission (a score of ≤10 on the Hamilton Rating Scale for Depression).
A total of 121 patients were included. At study end, 45% of participants in the sertraline group, 73% of those in the S+NPE group and 81% of those in the S+PAE group achieved remission (P = 0.001). A shorter time to remission was observed in the S+PAE group than in the sertraline-only group.
Physical exercise may be a safe and effective augmentation to antidepressant therapy in late-life major depression.
N = 2 Born-Infeld attractors Ferrara, S.; Porrati, M.; Sagnotti, A.
The journal of high energy physics,
12/2014, Letnik:
2014, Številka:
12
Journal Article
Recenzirano
Odprti dostop
A
bstract
We derive new types of U(1)
n
Born-Infeld actions based on
N
= 2 special geometry in four dimensions. As in the single vector multiplet (
n
= 1) case, the non-linear actions originate, in a ...particular limit, from quadratic expressions in the Maxwell fields. The dynamics is encoded in a set of coefficients
d
ABC
related to the third derivative of the holomorphic prepotential and in an SU(2) triplet of
N
= 2 Fayet-Iliopoulos charges, which must be suitably chosen to preserve a residual
N
= 1 supersymmetry.
Food-induced thermogenesis is generally reported to be higher in the morning, although contrasting results exist because of differences in experimental settings related to the preceding fasting, ...exercise, sleeping and dieting. To definitively answer to this issue, we compared the calorimetric and metabolic responses to identical meals consumed at 0800 hours and at 2000 hours by healthy volunteers, after standardized diet, physical activity, duration of fast and resting.
Twenty subjects (age range 20-35 years, body mass index=19-26 kg m(-)(2)) were enrolled to a randomized cross-over trial. They randomly received the same standard meal in the morning and, 7 days after, in the evening, or vice versa. A 30-min basal calorimetry was performed; a further 60-min calorimetry was done 120-min after the beginning of the meal. Blood samples were drawn every 30-min for 180-min. General linear models, adjusted for period and carry-over, were used to evaluate the 'morning effect', that is, the difference of morning delta (after-meal minus fasting values) minus evening delta (after-meal minus fasting values) of the variables.
Fasting resting metabolic rate (RMR) did not change from morning to evening; after-meal RMR values were significantly higher after the morning meal (1916; 95% confidence interval (CI)=1792, 2041 vs 1756; 1648, 1863 kcal; P<0.001). RMR was significantly increased after the morning meal (90.5; 95% CI=40.4, 140.6 kcal; P<0.001), whereas differences in areas-under-the-curve for glucose (-1800; -2564,-1036 mg dl(-1) × h, P<0.001), log-insulin (-0.19; -0.30,-0.07 μU ml(-1) × h; P=0.001) and fatty free acid concentrations (-16.1;-30.0,-2.09 mmol l(-1) × h; P=0.024) were significantly lower. Delayed and larger increases in glucose and insulin concentrations were found after the evening meals.
The same meal consumed in the evening determined a lower RMR, and increased glycemic/insulinemic responses, suggesting circadian variations in the energy expenditure and metabolic pattern of healthy individuals. The timing of meals should probably be considered when nutritional recommendations are given.
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