Observing the Structure of the Landscape with the CMB Experiments

Assuming that inflation happened through a series of tunneling in the string theory landscape, it is argued that one can determine the structure of vacua using precise measurements of the scalar spectral index and tensor perturbations at large scales. It is shown that for a vacuum structure where the energy gap between the minima is constant, i.e. $\epsilon_i=i m_f^4$, one obtains the scalar spectral index, $n_s$, to be $\simeq 0.9687$, for the modes that exit the horizon 60 e-folds before the end of inflation. Alternatively, for a vacuum structure in which the energy gap increases linearly with the vacuum index, i.e. $\epsilon_i=\frac{i^2}{2} m_f^4$, $n_s$ turns out to be $\simeq 0.9614$. Both these two models are motivated within the string theory landscape using flux-compactification and their predictions for scalar spectral index are compatible with WMAP results. For both these two models, the results for the scalar spectral index turn out to be independent of $m_f$. Nonetheless, assuming that inflation started at Planckian energies and that there had been successful thermalization at each step, one can constrain $m_f<2.6069\times 10^{-5} m_P$ and $m_f<6.5396\times 10^{-7} m_P$ in these two models, respectively. Violation of the single-field consistency relation between the tensor and scalar spectra is another prediction of chain inflation models. This corresponds to having a smaller tensor/scalar ratio at large scales in comparison with the slow-roll counterparts. Similar to slow-roll inflation, it is argued that one can reconstruct the vacuum structure using the CMB experiments.Comment: v1: 8 pages, 2 figures; v2: grammatical typos corrected, results unchanged v3: To be published in JCA

Comparison of the In Vitro Fermentation Characteristic of Fractionated Alfalfa and Sainfoin

Alfalfa and sainfoin leaves were lyophilized and ground (A, S, respectively) or were fractionated into soluble (ASOL, SSOL) and insoluble (AINS, SINS)components and lyophilized and incubated in vitro with diluted ruminal fluid for 24h. Whole leaf and soluble fractions were also incubated with polyethylene glycol 8000 (PEG). Gas production (GP), ammonia concentration [NH3] and volatile fatty acid (VFA) production were lower (P\u3c 0.05) from S and SSOL than from A and ASOL Insoluble fractions differed only in [NH3] (SINS \u3c AINS, P \u3c 0.05). Inclusion of PEG increased (P \u3c 0.05) GP, [NH3] and VFA production from whole leaf and soluble fractions of sainfoin, but not alfalfa. Inactivating the condensed tannins in sainfoin with PEG overcame differences in degradability between these two forages

Sustaining remote-area programs: retinal camera use by Aboriginal health workers and nurses in a Kimberley partnership

Objective: to describe how a novel program of diabetic retinopathy screening was conceived, refined and sustained in a remote region over 10 years, and to evaluate its activities and outcomes. Design: program description; analysis of regional screening database; audit of electronic client registers of Aboriginal community controlled health services (ACCHSs). Setting and participants: 1318 Aboriginal and 271 non-Aboriginal individuals who underwent retinal screening in the 5 years to September 2004 in the Kimberley region of north-west Australia; 11 758 regular local Aboriginal clients of Kimberley ACCHSs as at January 2005. Main outcome measures: characteristics of clients and camera operators, prevalence of retinopathy, photograph quality, screening intervals and coverage. Results: among Aboriginal clients, 21% had diabetic retinopathy: 19% with nonproliferative retinopathy, 1.2% with proliferative retinopathy, and 2.8% with maculopathy. Corresponding figures for non-Aboriginal clients were 11%, 11%, 0 and 0.4%, respectively. Photograph quality was generally high, and better for non-Aboriginal clients, younger Aboriginal clients and from 2002 (when mydriatic use became universal). Quality was not related to operator qualifications, certification or experience. Of 718 regular Aboriginal clients with diabetes on local ACCHS databases, 48% had a record of retinal screening within the previous 18 months, and 65% within the previous 30 months. Conclusions: Screening for diabetic retinopathy performed locally by Aboriginal health workers and nurses with fundus cameras can be successfully sustained with regional support. Formal certification appears unnecessary. Data sharing across services, client recall and point-of-care prompts generated by electronic information systems, together with policies making primary care providers responsible for care coordination, support appropriate timely screening

Communication rehabilitation in sub-Saharan Africa: The role of speech and language therapists

Background: Workforce factors present a significant barrier to the development of rehabilitation services for people with communication disabilities in sub-Saharan Africa (SSA). Exploring how the work of speech and language therapists (SLTs) in the region is organised and delivered can provide insight into existing services, areas for future workforce development and improved rehabilitation access for people with communication disability. Objectives: This paper describes the employment and service provision patterns and work roles of a sample of SLTs in SSA. Method: A broad, purpose-designed, mixed-methods survey was designed to collect data from SLTs living in Anglophone countries of SSA. Descriptive statistics and qualitative content analysis were undertaken. This paper reports on a subset of data from the wider survey. Results: A description of the employment and work roles of the 33 respondents to the survey and characteristics of their service users is presented. SLTs were commonly employed within private and not-for-profit sectors and frequently worked in temporary jobs. SLTs engaged in a range of work roles, including capacity building and training others. Services were provided by SLTs across age ranges, health conditions and settings, with paediatric, urban services commonly reported. Costs for service users and urban-centred services give indications of barriers to service access. Conclusion: Knowledge of the way in which speech and language therapy services are organised and provided has the potential to shape the development of communication disability rehabilitation in SSA. This research has identified a range of issues requiring consideration as the profession develops and grows

Atlantic bluefin tuna : a novel multistock spatial model for asessing population biomass

© The Author(s), 2011. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in PLoS One 6 (2011): e27693, doi:10.1371/journal.pone.0027693.Atlantic bluefin tuna (Thunnus thynnus) is considered to be overfished, but the status of its populations has been debated, partly because of uncertainties regarding the effects of mixing on fishing grounds. A better understanding of spatial structure and mixing may help fisheries managers to successfully rebuild populations to sustainable levels while maximizing catches. We formulate a new seasonally and spatially explicit fisheries model that is fitted to conventional and electronic tag data, historic catch-at-age reconstructions, and otolith microchemistry stock-composition data to improve the capacity to assess past, current, and future population sizes of Atlantic bluefin tuna. We apply the model to estimate spatial and temporal mixing of the eastern (Mediterranean) and western (Gulf of Mexico) populations, and to reconstruct abundances from 1950 to 2008. We show that western and eastern populations have been reduced to 17% and 33%, respectively, of 1950 spawning stock biomass levels. Overfishing to below the biomass that produces maximum sustainable yield occurred in the 1960s and the late 1990s for western and eastern populations, respectively. The model predicts that mixing depends on season, ontogeny, and location, and is highest in the western Atlantic. Assuming that future catches are zero, western and eastern populations are predicted to recover to levels at maximum sustainable yield by 2025 and 2015, respectively. However, the western population will not recover with catches of 1750 and 12,900 tonnes (the “rebuilding quotas”) in the western and eastern Atlantic, respectively, with or without closures in the Gulf of Mexico. If future catches are double the rebuilding quotas, then rebuilding of both populations will be compromised. If fishing were to continue in the eastern Atlantic at the unregulated levels of 2007, both stocks would continue to decline. Since populations mix on North Atlantic foraging grounds, successful rebuilding policies will benefit from trans-Atlantic cooperation.This work was supported by grants from the TAG A Giant Foundation, the Monterey Bay Aquarium Foundation, the Lenfest Ocean Program, Washington, DC, USA, the Canadian Fisheries and Oceans International Governance Strategies Fund and the National Oceanic and Atmospheric Administration (NOAA) of the United States

Altered hippocampal function in major depression despite intact structure and resting perfusion

Background: Hippocampal volume reductions in major depression have been frequently reported. However, evidence for functional abnormalities in the same region in depression has been less clear. We investigated hippocampal function in depression using functional magnetic resonance imaging (fMRI) and neuropsychological tasks tapping spatial memory function, with complementing measures of hippocampal volume and resting blood flow to aid interpretation. Method: A total of 20 patients with major depressive disorder (MDD) and a matched group of 20 healthy individuals participated. Participants underwent multimodal magnetic resonance imaging (MRI): fMRI during a spatial memory task, and structural MRI and resting blood flow measurements of the hippocampal region using arterial spin labelling. An offline battery of neuropsychological tests, including several measures of spatial memory, was also completed. Results: The fMRI analysis showed significant group differences in bilateral anterior regions of the hippocampus. While control participants showed task-dependent differences in blood oxygen level-dependent (BOLD) signal, depressed patients did not. No group differences were detected with regard to hippocampal volume or resting blood flow. Patients showed reduced performance in several offline neuropsychological measures. All group differences were independent of differences in hippocampal volume and hippocampal blood flow. Conclusions: Functional abnormalities of the hippocampus can be observed in patients with MDD even when the volume and resting perfusion in the same region appear normal. This suggests that changes in hippocampal function can be observed independently of structural abnormalities of the hippocampus in depression

Desensitizing Inflation from the Planck Scale

A new mechanism to control Planck-scale corrections to the inflationary eta parameter is proposed. A common approach to the eta problem is to impose a shift symmetry on the inflaton field. However, this symmetry has to remain unbroken by Planck-scale effects, which is a rather strong requirement on possible ultraviolet completions of the theory. In this paper, we show that the breaking of the shift symmetry by Planck-scale corrections can be systematically suppressed if the inflaton field interacts with a conformal sector. The inflaton then receives an anomalous dimension in the conformal field theory, which leads to sequestering of all dangerous high-energy corrections. We analyze a number of models where the mechanism can be seen in action. In our most detailed example we compute the exact anomalous dimensions via a-maximization and show that the eta problem can be solved using only weakly-coupled physics.Comment: 34 pages, 3 figures

Volume modulus inflection point inflation and the gravitino mass problem

Several models of inflection point inflation with the volume modulus as the inflaton are investigated. Non-perturbative superpotentials containing two gaugino condensation terms or one such term with threshold corrections are considered. It is shown that the gravitino mass may be much smaller than the Hubble scale during inflation if at least one of the non-perturbative terms has a positive exponent. Higher order corrections to the Kahler potential have to be taken into account in such models. Those corrections are used to stabilize the potential in the axion direction in the vicinity of the inflection point. Models with only negative exponents require uplifting and in consequence have the supersymmetry breaking scale higher than the inflation scale. Fine-tuning of parameters and initial conditions is analyzed in some detail for both types of models. It is found that fine-tuning of parameters in models with heavy gravitino is much stronger than in models with light gravitino. It is shown that recently proposed time dependent potentials can provide a solution to the problem of the initial conditions only in models with heavy gravitino. Such potentials can not be used to relax fine tuning of parameters in any model because this would lead to values of the spectral index well outside the experimental bounds.Comment: 27 pages, 9 figures, comments and references added, version to be publishe

Decreasing physical and verbal aggression in a brain injured nursing home resident

Following a traumatic brain injury, patients often suffer a series of psychological and psychiatric sequalae. This study presents the case of Mr. K, a 52-year-old brain-injured nursing home resident who exhibited problematic physical aggression and verbal abuse toward staff and residents. His problem behaviors were intertwined with an ethical issue involving a heterosexual relationship with another resident who also was brain injured. Following a functional assessment of antecedents and consequences, a differential reinforcement of other behavior (DRO) schedule was implemented. Specifically, the resident was rewarded with short-term and long-term reinforcers following periods of time during which behaviors other than the target behavior were emitted. Although the behavior plan was successful, it resulted in a more noticeable decrease in physically aggressive behaviors than verbally abusive behaviors. Implications include increasing awareness of use of behavior plans in nursing homes and of ethical and behavioral issues associated with sexuality among nursing home residents