The relationship of dementia prevalence in older adults with intellectual disability (ID) to age and severity of ID

Background: Previous research has shown that adults with intellectual disability (ID) may be more at risk of developing dementia in old age than expected. However, the effect of age and ID severity on dementia prevalence rates has never been reported. We investigated the predictions that older adults with ID should have high prevalence rates of dementia that differ between ID severity groups and that the age-associated risk should be shifted to a younger age relative to the general population. Method: A two-staged epidemiological survey of 281 adults with ID without Down syndrome (DS) aged >60 years; participants who screened positive with a memory task, informant-reported change in function or with the Dementia Questionnaire for Persons with Mental Retardation (DMR) underwent a detailed assessment. Diagnoses were made by psychiatrists according to international criteria. Prevalence rates were compared with UK prevalence and European consensus rates using standardized morbidity ratios (SMRs). Results: Dementia was more common in this population (prevalence of 18.3%, SMR 2.77 in those aged >65 years). Prevalence rates did not differ between mild, moderate and severe ID groups. Age was a strong risk factor and was not influenced by sex or ID severity. As predicted, SMRs were higher for younger age groups compared to older age groups, indicating a relative shift in age-associated risk. Conclusions: Criteria-defined dementia is 2–3 times more common in the ID population, with a shift in risk to younger age groups compared to the general population

A note on dual giant gravitons in AdS4×CP3AdS_{4}\times \mathbb{CP}^{3}

We study some of the properties of dual giant gravitons - D2-branes wrapped on an $S^{2}\subset AdS_{4}$ - in type IIA string theory on $AdS_{4}\times \mathbb{CP}^{3}$. In particular we confirm that the spectrum of small fluctuations about the giant is both real and independent of the size of the graviton. We also extend previously developed techniques for attaching open strings to giants to this D2-brane giant and focus on two particular limits of the resulting string sigma model: In the pp-wave limit we quantize the string and compute the spectrum of bosonic excitations while in the semiclassical limit, we read off the fast string Polyakov action and comment on the comparison to the Landau-Lifshitz action for the dual open spin chain.Comment: v3 significantly changed: added coupling to RR 1-form and turned on worldvolume gauge field, computed gauge field fluctuation, added comments on closure of the sl(2) sector and re-written to improve clarity. This version published in JHE

Unconventional superconductivity in the cage type compound Sc5_5Rh6_6Sn18_{18}

We have examined the superconducting ground state properties of the caged type compound Sc$_5$Rh$_6$Sn$_{18}$ using magnetization, heat capacity, and muon-spin relaxation or rotation ($\mu$SR) measurements. Magnetization measurements indicate type-II superconductivity with an upper critical field $\mu_0H_{c2}(0)$ = 7.24 T. The zero-field cooled and field cooled susceptibility measurements unveil an onset of diamagnetic signal below $T_{\bf c}$ = 4.4 K. The interpretation of the heat capacity results below $T_{\bf c}$ using the $\alpha-$BCS model unveils the value of $\alpha$ = 2.65, which gives the dimensionless ratio 2$\Delta(0)/k_B T_{\bf c}$ = 5.3, intimating that Sc$_5$Rh$_6$Sn$_{18}$ is a strong-coupling BCS superconductor. The zero-field $\mu$SR measurements in the longitudinal geometry exhibit a signature of a spontaneous appearance of the internal magnetic field below the superconducting transition temperature, indicating that the superconducting state is characterized by the broken time-reversal symmetry (TRS). We have compared the results of broken TRS in Sc$_5$Rh$_6$Sn$_{18}$ with that observed in R$_5$Rh$_6$Sn$_{18}$ (R = Lu and Y).Comment: 6 pages, 4 figures. arXiv admin note: text overlap with arXiv:1411.687

The hall effect in quantum critical CeAuSb₂

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Field tuned critical fluctuations in YFe2Al10: Evidence from magnetization, 27Al (NMR, NQR) investigations

We report magnetization, specific heat, and NMR investigations on YFe2Al10 over a wide range in temperature and magnetic field and zero field (NQR) measurements. Magnetic susceptibility, specific heat and spin-lattice relaxation rate divided by T (1/T1T) follow a weak power law (T^-0.4) temperature dependence, which is a signature of critical fluctuations of Fe moments. The value of the Sommerfeld-Wilson ratio and linear relation between 1/T1T and chi(T) suggest the existence of ferromagnetic correlations in this system. No magnetic ordering down to 50 mK in Cp(T) and the unusual temperature and field scaling of the bulk and NMR data are associated with a magnetic instability which drives the system to quantum criticality. The magnetic properties of the system are tuned by field wherein ferromagnetic fluctuations are suppressed and a crossover from quantum critical to FL behavior is observed with increasing magnetic field

Abundancia, diversidad y distribución de juveniles de peces en estuarios con y sin manglares en áreas templadas de Sudáfrica

Mangroves in tropical and subtropical regions have been well documented in terms of the advantages they provide and their role in structuring ichthyofaunal assemblages, but little is known about their warm temperate counterparts. The study aimed to investigate the importance of warm temperate mangroves by comparing the abundance, diversity and distribution of small fishes in mangrove and non-mangrove estuaries in warm temperate South Africa. A 50x2 m (12-mm mesh) seine net was used over three summer seasons to sample small fishes in the Gonubie, Qora, Nahoon and Xhora estuaries (the latter two being mangrove estuaries). Fish abundance and diversity showed little variation among estuaries, despite the presence of mangroves. Estuaries in warm temperate areas are not only at the edge of mangrove distribution, but also offer alternative habitats which lend similar advantages to fish survival. It appears that warm temperate ichthyofauna have not yet evolved a dependence on mangrove systems in terms of the food, refuge and other ecological services they provide. Understanding the function of habitats and their value in enhancing fish survival in estuarine nursery areas is essential for fish conservation.El papel de los manglares en la estructuración de las comunidades de peces en regiones tropicales y subtropicales está bien documentado, sin embargo, es poco conocido en las zonas templadas. El estudio investiga la importancia de los manglares de zonas templadas comparando la abundancia, diversidad y distribución de juveniles de peces en estuarios con y sin manglares de Sudáfrica. Se utilizó una red de cerco de 50 m (12 mm de malla) durante tres veranos para muestrear juveniles de peces en cuatro estuarios: Gonubie, Qora, Nahoon y Xhora (los dos últimos con manglares). La abundancia y diversidad de peces mostró una escasa variación entre estuarios, a pesar de la presencia o ausencia de manglares. Los estuarios de las zonas templadas están en los límites de distribución de los manglares y pueden, además, favorecer la supervivencia de los peces. Estos resultados implicarían que la ictiofauna no ha evolucionado todavía en sistemas de manglares en función de las ventajas (ej. alimento, refugio) que pueden proporcionar estos ecosistemas. El estudio de estos hábitats y su valor como refugio de los juveniles de peces es esencial para la conservación de estas especies

Assessing Specific Cognitive Deficits Associated with Dementia in Older Adults with Down Syndrome: Use and Validity of the Arizona Cognitive Test Battery (ACTB)

BACKGROUND: Down syndrome is associated with specific cognitive deficits. Alongside this, older adults with Down syndrome are a high risk group for dementia. The Arizona Cognitive Test Battery (ACTB), a cognitive assessment battery specifically developed for use with individuals with Down syndrome, has been proposed for use as outcome measures for clinical trials in this population. It has not been validated in older adults with Down syndrome. This study aims to assess the use and validity of the ACTB in older adults with Down syndrome. METHODS: Participants with Down syndrome aged 45 and over were assessed using the ACTB, standard tabletop tests and informant ratings. RESULTS: Assessment outcomes of 49 participants were analysed. Of these, 19 (39%) had a diagnosis of dementia or possible dementia. Most participants were able to attempt most of the tasks, although some tasks had high floor effects (including CANTAB Intra-Extra Dimensional shift stages completed and Modified Dots Task). Of the ACTB tasks, statistically significant differences were observed between the dementia and no dementia groups on CANTAB Simple Reaction Time median latency, NEPSY Visuomotor Precision-Car and Motorbike and CANTAB Paired Associates Learning stages completed. No significant differences were observed for CANTAB Intra-Extra Dimensional Shift, Modified Dots Task, Finger Sequencing, NEPSY Visuomotor precision-Train and Car and CANTAB Paired Associates Learning first trial memory score. Several of the tasks in the ACTB can be used in older adults with Down syndrome and have mild to moderate concurrent validity when compared to tabletop tests and informant ratings, although this varies on a test by test basis. CONCLUSIONS: Overall, scores for a number of tests in the ACTB were similar when comparing dementia and no dementia groups of older adults with Down syndrome, suggesting that it would not be an appropriate outcome measure of cognitive function for clinical trials of dementia treatments without further modification and validation

The effect of beef production system on proximate composition and fatty acid profile of three beef muscles

In this study the effects of animal age combined with feeding regime and the utilisation of a beta-agonist (within a grain-fed system) on proximate composition and fatty acid profile of M. longissimus lumborum (LL), M. biceps femoris (BF), and M. semitendinosus (ST) were determined. Eighty Bonsmara steers consisting of A-age (0 permanent incisors) grain-fed (AC) and grain-fed supplemented with a beta-agonist, zilpaterol (AZ) (n = 20) grass-fed AB-age (1 - 2 permanent incisors; AB) (n = 20), and B-age (3 - 6 permanent incisors; B) (n = 20) animals were used. These four groups are representative of cattle slaughtered in South Africa and were treated as four production systems. The chemical composition of all three muscles showed that zilpaterol increased protein and reduced muscle fat contents of meat. All the muscles of both grass-fed groups (AB and B) had significantly higher content of certain desirable fatty acids (FAs) such as conjugated linoleic acid (CLA), omega-3 (n-3) FAs, branched chain saturated phytanic acid, and a lower omega-6/omega-3 (n-6/n-3) ratio than the two grain-fed groups (AC and AZ). The FA composition of grain-fed beef muscle was generally not influenced by the use of zilpaterol except for a tendency towards higher n-6 polyunsaturated fatty acid (PUFA) in beta-agonist produced beef. This was mainly due to higher levels of linoleic acid in LL and ST muscles and higher CLA in BF muscle of AZ animals. Phytanic acid was also higher in BF muscle of the AZ group compared to AC. Differences in animal age among grass-fed animals (AB vs. B) had minimal effect on FA composition of grass-fed beef. We can conclude that differences in FA composition of the three muscles are influenced mainly by feeding regime and less by differences in production factors within feeding regimes.Keywords: Animal age, grain feeding, grass feeding, zilpatero