An Alternative Parameterization of R-matrix Theory

An alternative parameterization of R-matrix theory is presented which is mathematically equivalent to the standard approach, but possesses features which simplify the fitting of experimental data. In particular there are no level shifts and no boundary-condition constants which allows the positions and partial widths of an arbitrary number levels to be easily fixed in an analysis. These alternative parameters can be converted to standard R-matrix parameters by a straightforward matrix diagonalization procedure. In addition it is possible to express the collision matrix directly in terms of the alternative parameters.Comment: 8 pages; accepted for publication in Phys. Rev. C; expanded Sec. IV, added Sec. VI, added Appendix, corrected typo

Online peer support for students

While many UK higher education institutions have websites offering information and advice on common student problems, interactive online support is less common. This article describes a project developing internet-based mutual support for students experiencing psychological problems at University College London

The 8^8B Neutrino Spectrum

Knowledge of the energy spectrum of $^8$B neutrinos is an important ingredient for interpreting experiments that detect energetic neutrinos from the Sun. The neutrino spectrum deviates from the allowed approximation because of the broad alpha-unstable $^8$Be final state and recoil order corrections to the beta decay. We have measured the total energy of the alpha particles emitted following the beta decay of $^8$B. The measured spectrum is inconsistent with some previous measurements, in particular with a recent experiment of comparable precision. The beta decay strength function for the transition from $^8$B to the accessible excitation energies in $^8$Be is fit to the alpha energy spectrum using the R-matrix approach. Both the positron and neutrino energy spectra, corrected for recoil order effects, are constructed from the strength function. The positron spectrum is in good agreement with a previous direct measurement. The neutrino spectrum disagrees with previous experiments, particularly for neutrino energies above 12 MeV.Comment: 15 pages, 13 figures, 4 tables, submitted to Phys. Rev. C, typos correcte

Application of energy and angular momentum balance to gravitational radiation reaction for binary systems with spin-orbit coupling

We study gravitational radiation reaction in the equations of motion for binary systems with spin-orbit coupling, at order (v/c)^7 beyond Newtonian gravity, or O(v/c)^2 beyond the leading radiation reaction effects for non-spinning bodies. We use expressions for the energy and angular momentum flux at infinity that include spin-orbit corrections, together with an assumption of energy and angular momentum balance, to derive equations of motion that are valid for general orbits and for a class of coordinate gauges. We show that the equations of motion are compatible with those derived earlier by a direct calculation.Comment: 12 pages, submitted to General Relativity and Gravitatio

Developmental sensory experience balances cortical excitation and inhibition.

Early in life, neural circuits are highly susceptible to outside influences. The organization of the primary auditory cortex (A1) in particular is governed by acoustic experience during the critical period, an epoch near the beginning of postnatal development throughout which cortical synapses and networks are especially plastic. This neonatal sensitivity to the pattern of sensory inputs is believed to be essential for constructing stable and adequately adapted representations of the auditory world and for the acquisition of language skills by children. One important principle of synaptic organization in mature brains is the balance between excitation and inhibition, which controls receptive field structure and spatiotemporal flow of neural activity, but it is unknown how and when this excitatory-inhibitory balance is initially established and calibrated. Here we use whole-cell recording to determine the processes underlying the development of synaptic receptive fields in rat A1. We find that, immediately after the onset of hearing, sensory-evoked excitatory and inhibitory responses are equally strong, although inhibition is less stimulus-selective and mismatched with excitation. However, during the third week of postnatal development, excitation and inhibition become highly correlated. Patterned sensory stimulation drives coordinated synaptic changes across receptive fields, rapidly improves excitatory-inhibitory coupling and prevents further exposure-induced modifications. Thus, the pace of cortical synaptic receptive field development is set by progressive, experience-dependent refinement of intracortical inhibition

Astrophysical SS factor for the 15N(p,γ)16O{}^{15}{\rm N}(p,\gamma){}^{16}{\rm O} reaction from RR-matrix analysis and asymptotic normalization coefficient for 16O→15N+p{}^{16}{\rm O} \to {}^{15}{\rm N} + p. Is any fit acceptable?

The $^{15}{\rm N}(p,\gamma)^{16}{\rm O}$ reaction provides a path from the CN cycle to the CNO bi-cycle and CNO tri-cycle. The measured astrophysical factor for this reaction is dominated by resonant capture through two strong $J^{\pi}=1^{-}$ resonances at $E_{R}= 312$ and 962 keV and direct capture to the ground state. Recently, a new measurement of the astrophysical factor for the $^{15}{\rm N}(p,\gamma)^{16}{\rm O}$ reaction has been published [P. J. LeBlanc {\it et al.}, Phys. Rev. {\bf C 82}, 055804 (2010)]. The analysis has been done using the $R$-matrix approach with unconstrained variation of all parameters including the asymptotic normalization coefficient (ANC). The best fit has been obtained for the square of the ANC $C^{2}= 539.2$ fm${}^{-1}$, which exceeds the previously measured value by a factor of $\approx 3$. Here we present a new $R$-matrix analysis of the Notre Dame-LUNA data with the fixed within the experimental uncertainties square of the ANC $C^{2}=200.34$ fm${}^{-1}$. Rather than varying the ANC we add the contribution from a background resonance that effectively takes into account contributions from higher levels. Altogether we present 8 fits, five unconstrained and three constrained. In all the fits the ANC is fixed at the previously determined experimental value $C^{2}=200.34$ fm${}^{-1}$. For the unconstrained fit with the boundary condition $B_{c}=S_{c}(E_{2})$, where $E_{2}$ is the energy of the second level, we get $S(0)=39.0 \pm 1.1$ keVb and normalized ${\tilde \chi}^{2}=1.84$, i.e. the result which is similar to [P. J. LeBlanc {\it et al.}, Phys. Rev. {\bf C 82}, 055804 (2010)]. From all our fits we get the range $33.1 \leq S(0) \leq 40.1$ keVb which overlaps with the result of [P. J. LeBlanc {\it et al.}, Phys. Rev. {\bf C 82}, 055804 (2010)]. We address also physical interpretation of the fitting parameters.Comment: Submitted to PR

A content analysis of alcohol imagery in season 2 of The Kardashians

Aims: The aim of the current study was to quantify the amount of alcohol content and branding in season 2 of the reality TV show 'The Kardashians'. Methods: Content analysis of alcohol content in all 10 episodes of season 2 of 'The Kardashians' were viewed, and alcohol content measured using 1-min interval coding. The presence of alcohol in the following 4 categories was noted: (1) Actual use, (2) Implied use, (3) Other Alcohol Reference, and (4) Brand Appearance. Results: Alcohol content was seen across all 10 episodes. Actual alcohol use (wine/champagne/cocktails) was seen in 6 episodes across 13 intervals. Implied, alcohol use was seen in all 10 episodes across 74 intervals. Alcohol branding was seen in 6 episodes, across 23 intervals. The Tequila brand 818, owned by Kendall Jenner, was seen 65 times across 17 intervals. Conclusions: The current study shows that alcohol content was highly prevalent in season 2 of The Kardashians. This programme was popular on the Disney+ streaming platform and likely resulted in widespread population exposure to alcohol content and branding, particularly to a brand owned by Kendall Jenner. Current rules and regulations are not sufficient to protect against exposure to this potentially harmful content. Potential abstract for rapid communication (max 60 words) This study aimed to explore the amount of alcohol content in season 2 of the reality TV show 'The Kardashians' using 1-minute interval coding. Alcohol content was prevalent across all 10 episodes and occurred in 21% of intervals, branding was particularly prominent. Current regulations are not sufficient to protect against this potentially harmful content

The effective inflationary potential of constant-torsion emergent gravity

Constant-torsion emergent gravity (CTEG) has a Lagrangian quadratic in curvature and torsion, but without any Einstein--Hilbert term. CTEG is motivated by a unitary, power-counting renormalisable particle spectrum. The timelike axial torsion adopts a vacuum expectation value, and the Friedmann cosmology emerges dynamically on this torsion condensate. We show that this mechanism -- and the whole background cosmology of CTEG -- may be understood through the effective potential of a canonical single scalar field model. The effective potential allows for hilltop inflation in the early Universe. In the late Universe, the Hubble friction overdamps the final quadratic approach to the effective minimum at the condensate, where the value of the potential becomes the cosmological constant. We do not consider particle production through spin-torsion coupling, or running of Lagrangian parameters. The model must be completed if reheating and a separation of inflationary and dark energy scales are to be understood. It is suggested that the divergence of the potential at large values of the scalar is inconsistent with the linearised propagator analysis of CTEG around zero-torsion Minkowski spacetime. This background may therefore be a strongly coupled surface in CTEG.Comment: 15 pages, 7 figure

Psychological interventions for caregivers of people with bipolar disorder: A systematic review and meta-analysis

AIMS: Clinical guidelines recommend psychological interventions be offered to caregivers of people with bipolar disorder. However, there is little clarity about the efficacy of such interventions. This review examined the efficacy of psychological interventions in improving caregiver-focused outcomes, including burden, psychological symptoms and knowledge. METHOD: A systematic search for controlled trials was conducted using a combination of electronic database searches (PsycINFO, MEDLINE, and CENTRAL), and hand searches. Risk of bias was assessed using the Cochrane Collaboration tool. Outcomes were meta-analysed using Review Manager (RevMan). RESULTS: Nine studies met inclusion criteria. All meta-analyses compared psychoeducation to a control. At post-treatment there was a large effect of psychoeducation on burden (g = -0.8, 95% CI: -1.32, -0.27). However, there was high heterogeneity, confidence intervals were wide, and the effect was not maintained at follow-up. The apparent effect of psychoeducation on psychological symptoms was driven by a single outlying study. There was a very large effect on knowledge at post-treatment (g = 2.60, 95% CI: 1.39, 3.82) and follow-up (g =2.41, 95% CI: 0.85, 3.98). LIMITATIONS: There was considerable diversity in study methodology and quality. The number of included studies and sample sizes were small. CONCLUSIONS: This review provides tentative meta-analytic evidence for the efficacy of psychoeducation in improving caregiver burden at post-treatment, and knowledge at post-treatment and follow-up. Services could consider offering psychoeducation as part of a multi-disciplinary package of care. However, more methodologically rigorous research is needed before clinical recommendations can be made with confidence

'Between a rock and a hard place': family members' experiences of supporting a relative with bipolar disorder

Purpose: Clinical guidelines emphasise the central role of family members in supporting people with bipolar disorder. However, there has been little focus on the challenges family members face in supporting their relative. This qualitative study explored the challenges of providing support to a relative with bipolar disorder, and how family members attempted to meet these challenges. Factors that helped or hindered their efforts were also explored, including experiences of professional support. Methods: Semi-structured interviews were conducted with 18 family members (partners, parents, adult children, and siblings). Transcripts were analysed using the Framework approach. Results: Participants faced numerous challenges pertaining to the nature of the disorder and specific illness phases, their relative’s responses to their attempts to help, and the limitations of support from healthcare professionals. Although participants were resourceful in managing these challenges, they strongly valued professional input. Six themes were identified: ‘Not knowing: like being in a minefield’, ‘It’s out of my control: sitting waiting for the next thing to happen’, ‘Treading on eggshells’, ‘Picking up on signs’, ‘Times of crisis: between a rock and a hard place’, and ‘I have to make my voice heard’. Conclusions: Family members supporting a relative with bipolar disorder face significant challenges but show considerable resourcefulness in managing them. The findings underline the importance of input from healthcare professionals to help family members effectively support their relative and manage the challenges they face. Professional support should be strengths-based, and tailored to family members’ needs