Conformal Symmetries of Adiabatic Modes in Cosmology

We remark on the existence of non-linearly realized conformal symmetries for scalar adiabatic perturbations in cosmology. These conformal symmetries are present for any cosmological background, beyond any slow-roll or quasi-de Sitter approximation. The dilatation transformation shifts the curvature perturbation by a constant, and corresponds to the well-known symmetry under spatial rescaling. We argue that the scalar sector is also invariant under special conformal transformations, which shift the curvature perturbation by a term linear in the spatial coordinates. We discuss whether these conformal symmetries can be extended to include tensor perturbations. Tensor modes introduce their own set of non-linearly realized symmetries. We identify an infinite set of large gauge transformations which maintain the transverse, traceless gauge condition, while shifting the tensor mode non-trivially.Comment: 16 page

Linking posttraumatic stress disorder with eating disorders among Emirati university female students: The role of self-concealment

The link between posttraumatic stress disorder (PTSD) from past trauma, eating disorders, and psychiatric co-morbidity has been established. Whether self-concealment could influence these distress outcomes among traumatised Emirati university female students remains unclear. This study aimed to investigate whether the co-existing profiles of PTSD and self-concealment could impact eating disorder and psychiatric co-morbidity among female Emirati students. Using a convenience sampling method, the research was made known to students studying at a university in the United Arab Emirates. Four hundred and twenty-one female students completed questionnaires measuring PTSD, self-concealment, eating attitudes, and psychiatric co-morbidity in class. Latent profile analysis and multivariate analysis of variance were used respectively to identify the profiles for students and examine the differences between profile groups in distress outcomes. 38% met the criteria for PTSD. Using Latent Profile Analysis, profile 1 (moderate PTSD and self-concealment with high avoidance) had moderate PTSD symptoms with a high level of avoidance, and a moderate level of self-concealment. Profile 2 (moderate PTSD and self-concealment with low avoidance) had moderate PTSD symptoms with a low level of avoidance, and a similar level of self-concealment to profile 1. Profiles 3 (low PTSD group) and 4 (high PTSD group) had the lowest and highest levels of PTSD symptoms and self-concealment, respectively. Profile 4 showed significantly higher eating disorder symptoms compared to profile 3, and higher levels of psychiatric co-morbidity than the other three profiles. Having PTSD with a tendency to hide self-related secret could increase eating disorder symptoms along with other psychological difficulties

Vascular Response to Sildenafil Citrate in Aging and Age-Related Macular Degeneration.

Age-related macular degeneration (AMD) - the leading cause of vision loss in the elderly - share many risks factors as atherosclerosis, which exhibits loss of vascular compliance resulting from aging and oxidative stress. Here, we attempt to explore choroidal and retinal vascular compliance in patients with AMD by evaluating dynamic vascular changes using live ocular imaging following treatment with oral sildenafil citrate, a phosphodiesterase type 5 (PDE5) inhibitor and potent vasodilator. Enhanced-depth imaging optical coherence tomography (EDI-OCT) and OCT angiography (OCT-A) were performed on 46 eyes of 23 subjects, including 15 patients with non-exudative AMD in one eye and exudative AMD in the fellow eye, and 8 age-matched control subjects. Choroidal thickness, choroidal vascularity, and retinal vessel density were measured across the central macula at 1 and 3 hours after a 100 mg oral dose of sildenafil citrate. Baseline choroidal thickness was 172.1 ± 60.0 μm in non-exudative AMD eyes, 196.4 ± 89.8 μm in exudative AMD eyes, and 207.4 ± 77.7 μm in control eyes, with no difference between the 3 groups (P = 0.116). After sildenafil, choroidal thickness increased by 6.0% to 9.0% at 1 and 3 hours in all groups (P = 0.001-0.014). Eyes from older subjects were associated with choroidal thinning at baseline (P = 0.005) and showed less choroidal expansion at 1 hour and 3 hours after sildenafil (P = 0.001) regardless of AMD status (P = 0.666). The choroidal thickening appeared to be primarily attributed to expansion of the stroma rather than luminal component. Retinal vascular density remained unchanged after sildenafil in all 3 groups (P = 0.281-0.587). Together, our studies suggest that vascular response of the choroid to sildenafil decreases with age, but is not affected by the presence of non-exudative or exudative AMD, providing insight into changes in vessel compliance in aging and AMD

Improved Carotid and Mesenteric Blood Flows with the Use of 21% Oxygen During Resuscitation of Newborn Piglets with Severe Asphyxia

peer reviewe

Civic Crowdfunding for Social Work Research: Opportunities, Challenges and Strategies

Civic crowdfunding for research purposes has been an emerging trend in scientific fields over the past few years. This article presents findings from a mixed methods analysis of 152 social science research projects that campaigned for crowdfunding. A total of US$583,074 was raised through the support of 6,663 backers amongst the 150 successfully funded projects. This study offers specific lessons for social work researchers engaging in crowdfunding campaigns. The data show that projects supported by endorsers and initiated by faculties were able to solicit more backers and funds. Another key finding is that the campaigns that had videos for promotional purposes were the most successful, but video length does not affect backers’ consideration. The article presents the potential ethical challenges for social work researchers in this crowdfunding arena. In what may first appear to be a democratic and emancipatory space, decisions are actually made about what topics are worthy of financing by people who have access to the online platforms and the disposable income to back the project. Nevertheless, these platforms offer a route to research funding for academics, practitioners and service user groups in a context where funding from research councils and foundations is increasingly limited and competitive

Designing an Industrially Scalable, Flow-Based Synthesis for the Production of Nilotinib: Chemical Process Modeling and Economic Analysis

Nilotinib (Tasigna) is a drug used to treat chronic myelogenous leukemia (CML), a disease which currently affects over 100,000 people in the U.S. The drug is manufactured by Novartis and has been one of its most profitable, bringing in a total revenue of well over $2 billion USD in 2016. Novartis’s patent on Tasigna is set to expire in 2023 and cheaper, generic versions of the drug will soon be in great demand. An assessment of Novartis’s existing patent on the synthesis of Tasigna indicates many drawbacks in the current process. Namely, the Novartis synthesis requires multiple days of reaction, nearly a dozen steps, multiple solvent switching processes, and gives very low yields. On the other hand, work published by Buchwald and coworkers has shown an efficient method of synthesizing nilotinib in fewer than four steps, in less than 24 hours, and at >85$250 million USD/year even with a predicted 60% drop in generic drug price factored in. This, we envision, would serve as an important improvement in the efficiency of industrial level synthesis of a life-saving cancer drug

Mindfulness-based cognitive therapy v. group psychoeducation for people with generalised anxiety disorder: randomised controlled trial

Background: Research suggests that an 8-week mindfulness-based cognitive therapy (MBCT) course may be effective for generalised anxiety disorder (GAD). Aims: To compare changes in anxiety levels among participants with GAD randomly assigned to MBCT, cognitive–behavioural therapy-based psychoeducation and usual care. Method: In total, 182 participants with GAD were recruited (trial registration number: CUHK_CCT00267) and assigned to the three groups and followed for 5 months after baseline assessment with the two intervention groups followed for an additional 6 months. Primary outcomes were anxiety and worry levels. Results: Linear mixed models demonstrated significant group × time interaction (F(4,148) = 5.10, P = 0.001) effects for decreased anxiety for both the intervention groups relative to usual care. Significant group × time interaction effects were observed for worry and depressive symptoms and mental health-related quality of life for the psychoeducation group only. Conclusions: These results suggest that both of the interventions appear to be superior to usual care for the reduction of anxiety symptoms

Rapidly-Varying Speed of Sound, Scale Invariance and Non-Gaussian Signatures

We show that curvature perturbations acquire a scale invariant spectrum for any constant equation of state, provided the fluid has a suitably time-dependent sound speed. In order for modes to exit the physical horizon, and in order to solve the usual problems of standard big bang cosmology, we argue that the only allowed possibilities are inflationary (albeit not necessarily slow-roll) expansion or ekpyrotic contraction. Non-Gaussianities offer many distinguish features. As usual with a small sound speed, non-Gaussianity can be relatively large, around current sensitivity levels. For DBI-like lagrangians, the amplitude is negative in the inflationary branch, and can be either negative or positive in the ekpyrotic branch. Unlike the power spectrum, the three-point amplitude displays a large tilt that, in the expanding case, peaks on smallest scales. While the shape is predominantly of the equilateral type in the inflationary branch, as in DBI inflation, it is of the local form in the ekpyrotic branch. The tensor spectrum is also generically far from scale invariant. In the contracting case, for instance, tensors are strongly blue tilted, resulting in an unmeasurably small gravity wave amplitude on cosmic microwave background scales.Comment: 41 pages, 12 figures. v4: Few typos in equations (7.39) correcte