Nanosecond-Timescale Low Energy Switching of In-Plane Magnetic Tunnel Junctions through Dynamic Oersted-Field-Assisted Spin Hall Effect.

We investigate fast-pulse switching of in-plane-magnetized magnetic tunnel junctions (MTJs) within 3-terminal devices in which spin-transfer torque is applied to the MTJ by the giant spin Hall effect. We measure reliable switching, with write error rates down to 10-5, using current pulses as short as just 2 ns in duration. This represents the fastest reliable switching reported to date for any spin-torque-driven magnetic memory geometry and corresponds to a characteristic time scale that is significantly shorter than predicted possible within a macrospin model for in-plane MTJs subject to thermal fluctuations at room temperature. Using micromagnetic simulations, we show that in the three-terminal spin-Hall devices the Oersted magnetic field generated by the pulse current strongly modifies the magnetic dynamics excited by the spin-Hall torque, enabling this unanticipated performance improvement. Our results suggest that in-plane MTJs controlled by Oersted-field-assisted spin-Hall torque are a promising candidate for both cache memory applications requiring high speed and for cryogenic memories requiring low write energies.

Nonlinear Waves in the Terrestrial Quasiparallel Foreshock.

We provide strongly conclusive evidence that the cubic nonlinearity plays an important part in the evolution of the large amplitude magnetic structures in the terrestrial foreshock. Large amplitude nonlinear wave trains at frequencies above the proton cyclotron frequency are identified after nonharmonic slow variations are filtered out by applying the empirical mode decomposition. Numerical solutions of the derivative nonlinear Schrödinger equation, predicted analytically by the use of a pseudopotential approach, are found to be consistent with the observed wave forms. The approximate phase speed of these nonlinear waves, indicated by the parameters of numerical solutions, is of the order of the local Alfvén speed. We suggest that the feedback of the large amplitude fluctuations on background plasma is reflected in the evolution of the pseudopotential.

Are childhood factors predictive of adult health literacy? A longitudinal birth cohort analysis.

Health literacy (HL), defined as the ability of an individual to understand and appraise health information to make informed decisions on their health, helps maintain and improve one's health and thus reduce the use of healthcare services. There is a recognised global effort to address insufficient HL in early life and understand how HL develops. This study examined the association of a range of factors including educational, speech and language ability, health and healthcare engagement, sleep problems, mental health, demographic, environmental, and maternal factors at different childhood stages (from 5 years to 11 years) with later adult HL at age 25. HL was measured using a HL ordinal score (insufficient, limited, or sufficient) derived from the European Literacy Survey Questionnaire-short version (HLS-EU-Q16) within a large UK based birth cohort (Avon Longitudinal Study of Parents and Children: ALSPAC study). Univariate proportional odds logistic regression models for the probability of having higher levels of HL were developed. Results of analysis of 4248 participants showed that poorer speech and language ability (aged 9 years, OR 0.18 95% CI 0.04 to 0.78), internalising in child (age 11 years, OR 0.62 95% CI 0.5 to 0.78), child depression (age 9 years, OR 0.67 95% CI 0.52 to 0.86), and the presence of maternal depression (child age 5, OR 0.80 95% CI 0.66 to 0.96), reduced the odds of sufficient HL when adult. Our results suggest some useful markers to identify children at potential risk of low HL that could be targeted for research into future interventions within school settings, for example, child's speech and language capability. In addition, this study identified child and maternal mental health as factors associated with later development of limited HL and future research should consider what potential mechanisms might explain this link.

Integrating Narcissus-derived galanthamine production into traditional upland farming systems.

Alzheimer's disease (AD) is a disorder associated with progressive degeneration of memory and cognitive function. Galantamine is a licenced treatment for AD but supplies of the plant alkaloid that it is produced from, galanthamine, are limited. This three-year system study tested the potential to combine Narcissus-derived galanthamine production with grassland-based ruminant production. Replicate plots of permanent pasture were prepared with and without bulbs of Narcissus pseudonarcissus sown as lines into the sward. Two different fertiliser regimes were imposed. The above-ground green biomass of N. pseudonarcissus was harvested in early spring and the galanthamine yield determined. In the second harvest year a split-plot design was implemented with lines of N. pseudonarcissus cut annually and biennially. All plots were subsequently grazed by ewes and lambs and animal performance recorded. Incorporation of N. pseudonarcissus into grazed permanent pasture had no detrimental effects on the health or performance of the sheep which subsequently grazed the pasture. There was no consistency to the effects of fertiliser rates on galanthamine yields. There was no difference in overall galanthamine yield if N. pseudonarcissus was cut biennially (1.64 vs. 1.75 kg galanthamine/ha for annual combined vs biennial cuts respectively; s.e.d = 0.117 kg galanthamine/ha; ns). This study verified the feasibility of a dual cropping approach to producing plant-derived galanthamine.

Effects of allergen and trigger factor avoidance advice in primary care on asthma control: a randomized-controlled trial.

BACKGROUND: Allergy contributes significantly to asthma exacerbation, yet avoidance of triggers, in particular allergens, is rarely addressed in detail in regular asthma review in primary care. OBJECTIVE: To determine whether structured, individually tailored allergen and trigger avoidance advice, given as part of a primary care asthma review, improves lung function and asthma control. METHODS: In a randomized-controlled trial 214 adults with asthma in six general practices were either offered usual care during a primary care asthma review or usual care with additional allergen and trigger identification (by skin prick testing and structured allergy assessment) and avoidance advice according to a standardized protocol by trained practice nurses. Main outcome measures were lung function, asthma control, asthma self-efficacy. RESULTS: Both intervention groups were equivalent in demographic and asthma-related variables at baseline. At 3-6-month follow-up, patients receiving the allergen and trigger avoidance review showed significant improvements in lung function (assessed by blinded research nurses) compared with those receiving usual care. Significantly more patients in the intervention group than in the control group showed improvements in forced expiratory volume in 1 s > or =15%. No significant differences were found in self-report measures of asthma control. Asthma-specific self-efficacy improved in both groups but did not differ between groups. CONCLUSIONS: Allergen and trigger identification and avoidance advice, given as part of a structured asthma review delivered in primary care by nurses results in clinically important improvements in lung function but not self-report of asthma control. TRIAL REGISTRATION: ISRCTN45684820.

Why some adults with intellectual disability consult their general practitioner more than others.

BACKGROUND: This research identifies factors affecting why some adults with intellectual disability (AWIDs) consult their general practitioner (GP) more than others. Little is known about these factors, despite AWIDs having higher health needs and reduced longevity. Current barriers to accessing health care need to be understood and overcome to achieve improved health outcomes. METHODS: A secondary analysis of data obtained from a stratified randomised sample of AWIDs participating in a cluster randomised trial of hand held health records. The number of GP consultations was obtained retrospectively for the year preceding initial health interviews from GP records. AWIDs and their carers were given separate health interviews using identical/adapted questions where possible. RESULTS: Two hundred and one AWIDs and or their carers from 40 practices participated (response rate 64.6%) with GP consultation data extracted for 187 AWIDs. Overall consulting levels were low, 3.2 per annum for women and 2.2 for men. Increased age, gender (women) and type of carer (paid) were all significantly associated with increased consultations. Carers reporting health problems, medications reported by AWIDs, medications recorded in GP records, and pain reported by AWIDs were also significant factors affecting consultations to GP practices after adjustment for age and type of carer. CONCLUSIONS: Overall consultation rates were lower than expected, and affected by age, gender and type of carer. Targeted interventions are needed to improve attendance and promote health.

Monitored and modeled coral population dynamics and the refuge concept.

With large-scale impacts on coral reefs due to global climatic change projected to increase dramatically, and suitability of many areas for reef growth projected to decrease, the question arises whether particular settings might serve as refugia that can maintain higher coral populations than surrounding areas. We examine this hypothesis on a small, local scale in Honduras, western Caribbean. Dense coral thickets containing high numbers of the endangered coral Acropora cervicornis occur on offshore banks while being rare on the fringing reef on nearby Roatán. Geomorphological setting and community dynamics were evaluated and monitored from 1996 to 2005. A model of population dynamics was developed to test assumptions derived from monitoring. Coral cover on the fringing reef declined in 1998 from >30% to <20%, but the banks maintained areas of very dense coral cover (32% cover by A. cervicornis on the banks but <1% on the fringing reef). Bathymetry from satellite images showed the banks to be well-separated from the fringing reef, making asexual connectivity between banks and fringing reef impossible but protecting the banks from direct land-runoff during storms. Exposure to SE tradewinds also causes good flushing. Only four A. cervicornis recruits were recorded on the fringing reef over 6 years. Runoff associated with hurricanes caused greater mortality than did bleaching in 1998 and 2005 on the fringing reef, but not on the banks. Since 1870, our analysis suggests that corals on the banks may have been favored during 17 runoff events associated with tropical depressions and storms and potentially also during five bleaching events, but this is more uncertain. Our model suggests that under this disturbance regime, the banks will indeed maintain higher coral populations than the fringing reef and supports the assumption that offshore banks could serve as refugia with the capacity to subsidize depleted mainland populations.

A cryogenic spin-torque memory element with precessional magnetization dynamics.

We present a study of precessional magnetization switching in orthogonal spin-torque spin-valve devices at low temperatures. The samples consist of a spin-polarizing layer that is magnetized out-of-the film plane and an in-plane magnetized free and reference magnetic layer separated by non-magnetic metallic layers. We find coherent oscillations in the switching probability, characterized by high speed switching (~200 ps), error rates as low as 10-5 and decoherence effects at longer timescales (~1 ns). Our study, which is conducted over a wide range of parameter space (pulse amplitude and duration) with deep statistics, demonstrates that the switching dynamics are likely dominated by the action of the out-of-plane spin polarization, in contrast to in-plane spin-torque from the reference layer, as has been the case in most previous studies. Our results demonstrate that precessional spin-torque devices are well suited to a cryogenic environment, while at room temperature they have so far not exhibited coherent or reliable switching.

Temporal and between-site variation in helminth communities of bank voles ( Myodes glareolus) from N.E. Poland. 2. The infracommunity level.

The relative importance of temporal and spatial effects was assessed in helminth communities of bank voles (Myodes glareolus) in 3 woodland sites in N.E. Poland in the late summers of 1999 and 2002. Among common species the rank order of sites in relation to prevalence and abundance of infection was maintained between surveys. Site effects accounted for most of the deviance (in statistical models), and time was less important, so the exact location from which voles were sampled was of critical importance. The only exception was Syphacia petrusewiczi. In contrast, for derived measures such as species richness and diversity, most deviance was accounted for by host age, and the interaction between site and year was significant, implying that rank order of sites changed between years. Temporal effects on derived measures were generated primarily by a combination of relatively small changes in prevalence and abundance of the common, rather than the rare, species between the years of the study. In the medium-term, therefore, helminth communities of bank voles in N.E. Poland had a stable core, suggesting a substantial strong element of predictability.

Temporal and between-site variation in helminth communities of bank voles ( Myodes glareolus) from N.E. Poland. 1. Regional fauna and component community levels.

Helminth infections were studied in bank voles (Myodes glareolus) from 3 woodland sites in N.E. Poland in the late summers of 1999 and 2002, to assess the temporal stability of derived statistics describing the regional helminth fauna and component community structure, and spatial influence on the latter. Regional helminth fauna changed dramatically between the two years, primarily due to a fall in the abundance of Syphacia petrusewiczi but was partially compensated for by an increase in Mesocestoides lineatus and Cladotaenia globifera. It was dominated by nematodes overall, but more so in 1999 than in 2002 when larval cestodes were more frequent. Most derived parameters for component community structure varied considerably between sites and the two surveys, the hierarchical order for sites not being maintained between surveys. They were susceptible to the disproportionate influence of three relatively rare, unpredictable species with the greatest overall aggregated distribution among hosts. Jaccard's similarity index was less influenced by the rare species, showing greater stability between sites and across years. In conclusion, temporal variation confounded any site-specific characteristics of the summary measures quantified in this study and their usefulness is therefore restricted to the years in which the surveys were conducted.

Validation of a health literacy screening tool (REALM) in a UK population with coronary heart disease.

BACKGROUND: Health literacy (HL) has been recognized as an important public health issue in other developed countries such as the US. There is currently no HL screening tool valid for use in the UK. This study aimed to validate a US-developed HL screening tool (the Rapid Estimate for Adult Literacy in Medicine; REALM) for use in the UK against the UK's general literacy screening tool (the Basic Skills Agency Initial Assessment Test, BSAIT). METHODS: A cross-sectional survey involving 300 adult patients admitted to hospital for investigation of coronary heart disease were given the REALM and BSAIT tools to complete as well as specific questions considered likely to predict HL. These questions relate to the difficulty in understanding medical information, medical forms or instructions on tablets, frequency of reading books and whether the participant's job involves reading. RESULTS: The REALM was significantly correlated with the BSAIT (r = 0.70; P < 0.001), and significantly related to seven of the eight questions likely to be predictive of HL. CONCLUSIONS: This study has shown that the REALM has face, criterion and construct validity for use as an HL screening tool in the UK, in research and in everyday clinical practice. Further studies are needed to assess the prevalence of low HL in a wider population and to explore the links that may exist between low HL and poor health in the UK.

Late skin flap failure following cochlear implantation.

The objective of the study was to determine risk factors for late skin flap failure following cochlear implantation. The study design was a retrospective case series. Data were collated from 371 implanted patients over a ten-year period. Of these patients, 1.3 per cent (n = 5) developed late skin flap failure. It is concluded that skin flap failure is a significant, though relatively uncommon, complication of cochlear implant surgery. What causes flap failure and why it should occur in such a variable fashion are still largely unknown, though infection undoubtedly plays an important role. The aetiological factors associated with flap failure and possible prevention strategies are discussed.

Swallowing dysfunction in patients with unilateral vocal fold paralysis: aetiology and outcomes.

Although unilateral vocal fold palsy (UVFP) is a common problem, data relating to swallowing dysfunction are sparse. We reviewed the clinical findings (method of presentation, underlying diagnosis and position of the vocal folds) of 30 patients and conducted a follow-up telephone survey. Outcome measures used were direct visualization of fold function, position and compensation. In addition, standardized speech and language assessments for swallowing dysfunction and dysphonia were noted and compared to presentation. Our study indicates that 56 per cent of patients with UVFP have associated dysphagia. Outcome with speech therapy is significant, with 73 per cent showing improvement. These data indicate a significant link between UVFP and swallowing dysfunction. There is a marked therapeutic benefit from voice therapy. Further work is required to evaluate the long-term outcomes and establish the mechanism of swallowing dysfunction in these patients.

Si1-x Ge x /Si Interface Profiles Measured to Sub-Nanometer Precision Using uleSIMS Energy Sequencing.

The utility of energy sequencing for extracting an accurate matrix level interface profile using ultra-low energy SIMS (uleSIMS) is reported. Normally incident O2 (+) over an energy range of 0.25-2.5 keV were used to probe the interface between Si0.73Ge0.27/Si, which was also studied using high angle annular dark field scanning transmission electron microscopy (HAADF-STEM). All the SIMS profiles were linearized by taking the well understood matrix effects on ion yield and erosion rate into account. A method based on simultaneous fitting of the SIMS profiles measured at different energies is presented, which allows the intrinsic sample profile to be determined to sub-nanometer precision. Excellent agreement was found between the directly imaged HAADF-STEM interface and that derived from SIMS. Graphical Abstract ᅟ.

Co-inheritance of mutations in the uroporphyrinogen decarboxylase and hemochromatosis genes accelerates the onset of porphyria cutanea tarda.

Porphyria cutanea tarda is a skin disease caused by photosensitization by porphyrins whose accumulation is caused by deficiency of hepatic uroporphyrin- ogen decarboxylase activity. Mutations in the uroporphyrinogen decarboxylase gene are present in the low-penetrant, autosomal dominant familial form but not in the commoner sporadic form of porphyria cutanea tarda. We have investigated the relationship between age of onset of skin lesions and mutations (C282Y, H63D) in the hemochromatosis gene in familial (19 patients) and sporadic porphyria cutanea tarda (65 patients). Familial porphyria cutanea tarda was identified by mutational analysis of the uroporphyrinogen decarboxylase gene. Five previously described and eight novel mutations (A80S, R144P, L216Q, E218K, L282R, G303S, 402-403delGT, IVS2 + 2 delTAA) were identified. Homozygosity for the C282Y hemochromatosis mutation was associated with an earlier onset of skin lesions in both familial and sporadic porphyria cutanea tarda, the effect being more marked in familial porphyria cutanea tarda where anticipation was demonstrated in family studies. Analysis of the frequencies of hemochromatosis genotypes in each type of porphyria cutanea tarda indicated that C282Y homozygosity is an important susceptibility factor in both types but suggested that heterozygosity for this mutation has much less effect on the development of the disease.

The relationship between the parasitological prevalence of trypanosomal infections in cattle and herd average packed cell volume.

The relationship between prevalence of trypanosomal infections (Trypanosoma congolense) and average packed cell volume (PCV) in herds of communally managed adult Angoni breed cattle was investigated in four districts of eastern Zambia. In all areas, regression analyses showed that the herd average PCV decreased with increasing prevalence of trypanosomal infections. The slope of the equation between average PCV and trypanosome prevalence decreased with increasing prevalence of trypanosomal infections. For the same increase in prevalence of trypanosomal infection, the decrease in herd PCV was higher in the areas with low to medium prevalence. Season of sampling also determined the slope of the regression equation. For the same increase in prevalence of trypanosomal infection, the decrease in herd PCV was higher during the dry compared to the rainy season suggesting that trypanosomosis is less well tolerated during the dry season. Results from the study suggest that the relationship between the prevalence of trypanosomal infections and herd average PCV could be a useful tool in the management of trypanosomosis and planning of its control. Reasons for the spatial and temporal variations in the relationship are discussed.

Variations in packed red cell volume and trypanosome prevalence and relationships with reproductive traits in east African Zebu cows exposed to drug-resistant trypanosomes.

Approximately 320 East African Zebu cows over 36 months of age were monitored monthly from 1986 to 1992 in nine village herds in an area of high trypanosomiasis risk in southwest Ethiopia where there was resistance to all available trypanocidal drugs. Cows were individually treated with diminazene aceturate, either when they were detected parasitaemic and their packed red cell volume (PCV) decreased below 26%, or when they showed clinical signs of trypanosomiasis. The average annual monthly trypanosome prevalence was 24% and the number of treatments of diminazene aceturate per cow per year was 3.1, both of which increased with age. Mean PCV decreased and mean trypanosome prevalence increased during lactation. There was a significant linear association between the time detected parasitaemic during the first 150 days of lactation and calving interval. When corrected for frequency of parasitaemia and treatment there was also an average reduction of 8.4 +/- 2.6 days in calving interval per % unit increase in PCV. Age at first calving decreased by 0.44 +/- 0.26 months per % unit increase in mean PCV maintained between 24 and 30 months corrected for parasitaemia and treatment. The percentage of pregnancies terminating in abortions significantly increased from 6.8 +/- 1.0% to 10.4 +/- 1.3% when cows detected parasitaemic at least once during the last three months of pregnancy were compared with cows not detected parasitaemic. The largest increase to 19.4 +/- 4.3% was in cows with low mean PCVs < 22%. It was concluded that cows which were able to maintain higher than average PCVs when parasitaemic showed superior reproductive performance than those with lower than average PCVs.

Epidemiology of bovine trypanosomiasis in the Ghibe valley, southwest Ethiopia. 1. Tsetse challenge and its relationship to trypanosome prevalence in cattle.

In this, the first of a series of papers on the epidemiology of bovine trypanosomiasis in the Ghibe valley, southwest Ethiopia, the tsetse populations and their relationships to the prevalence of trypanosome infections in cattle are described. The tsetse challenge to cattle at two sites sites in the area was estimated as the product of tsetse relative density and the trypanosome infection rate in flies. The proportion of feeds taken by tsetse from cattle was also considered. Three tsetse species were detected in the area, Glossina pallidipes, G. fuscipes and G. morsitans submorsitans. A significant correlation (r = 0.60, P < 0.001) was observed between the mean monthly estimates of tsetse challenge due to G. pallidipes and the prevalence of trypanosome infections in cattle the following month at one site, whilst at the other, no significant relationship was observed (P = 0.08). The tsetse density at both sites showed seasonal changes which were related to the monthly rainfall. Finally, variations in tsetse density appeared to be the main factor responsible for variation in tsetse challenge and thus trypanosome prevalence in cattle.