878 research outputs found
On supersymmetry breaking and the Dijkgraaf-Vafa conjecture
We investigate the Dijkgraaf-Vafa proposal when supersymmetry is broken. We
consider U(N) SYM with chiral adjoint matter where the coupling constants in
the tree-level superpotential are promoted to chiral spurions. The holomorphic
part of the low-energy glueball superpotential can still be analyzed. We
compute the holomorphic supersymmetry breaking contributions using methods of
the geometry underlying the N=1 effective gauge theory viewed as a Whitham
system. We also study the change in the effective glueball superpotential using
perturbative supergraph techniques in the presence of spurions.Comment: 24 pages, LaTeX; minor changes, one reference added, version to
appear in JHE
Chiral supergravity actions and superforms
The superform construction of supergravity actions, christened the "ectoplasm
method," is based on the use of a closed super d-form in the case of d
space-time dimensions. In known examples, such superforms are obtained by
iteratively solving nontrivial cohomological problems. The latter usually makes
this scheme no less laborious than the normal coordinate method for deriving
component actions for matter-coupled supergravity. In this note we present an
alternative procedure to generate required superforms in four space-time
dimensions, which makes use of self-dual vector multiplets. It provides the
shortest derivation of chiral actions in two different theories: (i) N = 1 old
minimal supergravity; and (ii) N = 2 conformal supergravity. The N = 2
superform construction is developed here for the first time. Although our
consideration is restricted to the case of four dimensions, a generalization to
higher dimensions is plausible.Comment: 14 pages; V2: minor correction
A preliminary evaluation of a single session behavioural activation intervention to improve well-being and prevent depression in carers
Background: Major depressive disorder is predicted to be the lead cause of disease burden by 2030. Despite evidence suggesting that major depressive disorder can be prevented, little attention has been paid to developing interventions for this purpose. As research suggests that high levels of subjective well-being may protect against depression, an intervention that can enhance and maintain subjective well-being may assist in preventing major depressive disorder. Behavioural activation (BA) is a promising intervention that has been observed to both effectively treat depression and also enhance subjective well-being, even in a single session. Method: A randomised control design was used to investigate the efficacy of a single session of BA to boost well-being and reduce distress in a community sample of carers (N = 13), who may be at increased risk of major depressive disorder. Outcome measures assessed symptoms of depression, anxiety, stress, and well-being and the lifestyle factors of perceived environmental reward and the extent to which individuals lived in accordance with their personal values. Results: Generalised linear mixed modelling revealed significant group Ă— time interactions for stress scores and valued living, indicating a treatment effect on these outcomes. Conclusions: Findings provide preliminary support for the effectiveness of a single session BA intervention to improve outcomes of carers
Superspace calculation of the four-loop spectrum in N=6 supersymmetric Chern-Simons theories
Using N=2 superspace techniques we compute the four-loop spectrum of single
trace operators in the SU(2) x SU(2) sector of ABJM and ABJ supersymmetric
Chern-Simons theories. Our computation yields a four-loop contribution to the
function h^2(\lambda) (and its ABJ generalization) in the magnon dispersion
relation which has fixed maximum transcendentality and coincides with the
findings in components given in the revised versions of arXiv:0908.2463 and
arXiv:0912.3460. We also discuss possible scenarios for an all-loop function
h^2(\lambda) that interpolates between weak and strong couplings.Comment: LaTeX, feynmp, 34 pages; v2: typos corrected, formulations improved,
references adde
Generalized aggressive periodontitis in prepubertal age: description and comparison of two cases.
Aggressive periodontitis is a rare form of periodontal disease and it can involve both the deciduous dentition and the permanent one. It causes a rapid loss of periodontal attachment. The paper aims to describe two cases of severe generalized prepubertal periodontitis: the first child doesn't suffer from neither systemic diseases nor alteration of functionality of polymorphonuclear and periodontal disease involved both his deciduous dentition and the first permanent molars. The second child had a deficiency of functionality of polymorphonuclear but periodontal disease involved only primary dentition thanks to his immediate improvement of home dental hygiene. This comparison shows the importance of early diagnosis and especially of optimal dental oral hygiene. Infant healthcare professionals, as pediatric dentists and pediatricians, should have the necessary knowledge for early and correct diagnosis and clinical management of disease
Stepping Stones Triple P: The theoretical basis and development of an evidence-based positive parenting program for families with a child who has a disability.
Stepping Stones Triple P is the first in a series of programs based on the Triple P – Positive Parenting Program that has been specifically designed for families who have a child with a disability. This paper presents the rationale, theoretical foundations, historical development and distinguishing features of the program. The multi-level intervention adopts a self-regulation framework in consulting with parents that involves the promotion of parental self-sufficiency, selfefficacy, self-management skills, personal agency and problem-solving skills. This paper describes the key program design features, intervention techniques, model of clinical consultation, its clinical applicability, and empirical base. The 10-session individually administered version of the program, known as Standard Stepping Stones Triple P is described and the important role of training, supervision and agency support in disseminating the program is discussed
Behavioural activation interventions for depression and well-being
Behavioural activation (BA) treatments for depression require patients to change their overt behaviour so that they may have more rewarding experiences in their lives. Since one of the most promising ways to increase psychological wellbeing is to increase engagement in valued and enjoyable activities, there is good reason to believe that BA may also be an effective intervention to increase wellbeing. Enhancing well-being is an important goal because there is increasing recognition of the positive impact well-being has on many desirable life outcomes such as career success, marriage and health. Although BA has existed since the 1970s there have been surprisingly few quantitative reviews of the literature, and little research on the impact of BA on well-being. Thus, the overall aim of this project was to consolidate our understanding of the impact of BA and investigate the potential of BA interventions for enhancing well-being. Specifically, the goals were to (a) review the existing empirical research on the utility of BA for treating depression, (b) review the existing research on BA related to well-being, and (c) investigate the potential of this approach to increase the well-being of individuals who are not suffering from a mental health problem. Thus this research is unique in not only focusing on clinical, depressed, individuals, but also integrating research from the field of positive psychology as it looks at improving the well-being of individuals without depression.The first study consisted of a meta-analysis which sought to identify all randomised controlled trials of BA for depression. The goal of this study was to determine the effect of this approach, and examine the differential effectiveness of variants. Forty studies with 2,401 participants reporting symptoms of depression were included. The pooled effect size (Hedges’s g) indicated the difference between BA and control conditions at posttest was 0.91. For participants who satisfied the criteria for major depressive disorder (MDD) the overall effect size of 0.82 remained large and significant. No differences in effectiveness between BA and cognitive therapy were found. This is an important finding given that BA is a comparatively simple intervention that does not require difficult or complex skills from patients or therapists. Although more recent versions of the BA approach, such as Jacobson and colleagues’ contextual BA, generally yielded greater intervention effects compared with earlier variants, all variants produced effects of similar magnitude and differences between them were not statistically significant. Nevertheless, a focused evidence review indicated that Jacobson and colleagues’ contextual BA has the strongest evidence base and satisfies the APA’s Division 12 Task Force’s well-established designation for the treatment of MDD.Study 2, also a meta-analysis, sought to identify all randomised controlled studies which examined the effect of BA on well-being. Twenty studies with a total of 1,353 participants were included. The pooled effect size indicated that the difference in well-being between BA and control conditions at posttest was 0.52. This significant effect, which is comparable to the pooled effect achieved by positive psychology interventions, was found for nonclinical participants and participants with elevated symptoms of depression. This suggests that BA is a useful intervention for promoting the well-being of a range of populations in both clinical and nonclinical settings.Study 3 examined the effects on well-being of a group intervention consisting of a 4-week BA component followed by a 3-week mindfulness component, finishing with an integrating closure session. Sixteen nonclinical adults recruited from the community participated in this pretest-posttest, repeated measures study. Results showed moderate and significant improvements in psychological distress and several indices of well-being after the BA component. These improvements continued through the mindfulness component of the intervention such that effects were greater after participants had received the complete intervention. Half of the participants reported reliable and clinically significant improvement in the amount of time they felt happy after the intervention and a quarter of participants reported improvement at follow-up.Taken together, these results led to the conclusion that BA is a well-established and advantageous intervention for depression which is also an effective and viable intervention for well-being, regardless of individuals’ depression status. The use of BA as a first line treatment for depression is recommended. However, further research is needed to determine whether BA interventions can be made more efficient, and to determine the full extent of their potential to promote mental health
Covariant superspace approaches to supergravity
We provide a unified description of the three covariant superspace approaches
to conformal supergravity in four dimensions: (i) conformal
superspace; (ii) superspace; and (iii)
superspace. Each of them can be used to formulate general supergravity-matter
systems, although conformal superspace has the largest structure group and is
intimately related to the superconformal tensor calculus. We review the
structure of covariant projective multiplets and demonstrate how they are used
to describe pure and matter-coupled supergravity, including locally
superconformal off-shell sigma models. Higher-derivative invariants,
topological invariants and super-Weyl anomalies are also briefly discussed.Comment: 58 pages. Invited chapter for the "Handbook of Quantum Gravity" (Eds.
C. Bambi, L. Modesto and I.L. Shapiro, Springer, expected in 2023
4D N = 2 Supergravity and Projective Superspace
This paper presents a projective superspace formulation for 4D N = 2
matter-coupled supergravity. We first describe a variant superspace realization
for the N = 2 Weyl multiplet. It differs from that proposed by Howe in 1982 by
the choice of the structure group (SO(3,1) x SU(2) versus SO(3,1) x U(2)),
which implies that the super-Weyl transformations are generated by a
covariantly chiral parameter instead of a real unconstrained one. We introduce
various off-shell supermultiplets which are curved superspace analogues of the
superconformal projective multiplets in global supersymmetry and which describe
matter fields coupled to supergravity. A manifestly locally supersymmetric and
super-Weyl invariant action principle is given. Off-shell locally
supersymmetric nonlinear sigma models are presented in this new superspace.Comment: 26 pages, LaTeX, no figures; V2: comments and references added,
version published in JHEP; V3: typo in eq. (2.7e) correcte
Ectoplasm & Superspace Integration Measure for 2D Supergravity with Four Spinorial Supercurrents
Building on a previous derivation of the local chiral projector for a two
dimensional superspace with eight real supercharges, we provide the complete
density projection formula required for locally supersymmetrical theories in
this context. The derivation of this result is shown to be very efficient using
techniques based on the Ectoplasmic construction of local measures in
superspace.Comment: 18 pages, LaTeX; V2: minor changes, typos corrected, references
added; V3: version to appear in J. Phys. A: Math. Theor., some comments and
references added to address a referee reques
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