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Argon is commonly used as the sputtering medium for RF sputtering of insulators and is entrapped in the deposits. X-ray emission determination of argon in RF sputtered SiO2 was required as part of a study of the relationships between argon concentration in the deposits and their electrical and physical properties.
Concentrations ranging from 0.05 to 7.4 weight % argon were measured in deposits 0.5 to 5μ thick. Two techniques were used for standardization: (1) weight loss of deposits heated for several hours in a helium atmosphere at 600°C; (2) potassium Kα and chlorine Kα measurements on a KCl film of known thickness to infer argon mass/argon Kα net counts. Calibrations made using these procedures agreed to within 10% and are reliable to about ±25% on an absolute basis. Absorption of radiation by the deposits was taken into account and used to correct measured argon intensities for absorption.
Sputtering parameters which had major effects on argon concentration were the substrate temperature and the magnetic field applied during sputtering. Argon pressure and RF power were found to have lesser effects.
Analysis schemes for eleven rare earths (Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb) taken singly in Y-Fe garnet powders are presented. Straight-line calibrations result in all cases, usually over a range from below 0.5 wt.% to better than 6 wt.%. Errors were held to ±5-10% even using extraordinarily simple sample preparation techniques. Data are presented relating to the effects of particle size and sample preparation on precision and accuracy of the resulting analysis.
Landraces (including heritage varieties) are an important agrobiodiversity resource offering considerable value as a buffer against crop failures, as a crop for niche markets, and as a source of diversity for crop genetic improvement activities underpinning future food security. Home gardens are reservoirs of landrace diversity, but some of the accessions held in them are vulnerable or threatened with extinction. Those associated with seed saving networks have added security, for example, ca. 800 varieties are stored in the Heritage Seed Library (HSL) of Garden Organic, UK. In this study, Amplified Fragment Length Polymorphisms-based genetic analysis of accessions held in the HSL was used to (a) demonstrate the range of diversity in the collection, (b) characterize accessions to aid collection management and (c) promote broader use of the collection. In total, 171 accessions were included from six crops: Vicia faba L., Pisum sativum L., Daucus carota L., Cucumis sativus L., Lactuca sativa L. and Brassica oleracea L. var. acephala (DC.) Metzq. Average expected heterozygosity ranged from 0.18 to 0.28 in D. carota; 0.02–0.18 in P. sativum; 0.05–0.18 in L. sativa; 0.15–0.26 in B. oleracea var. acephala; 0.15–0.37 in C. sativus and 0.07–0.36 in V. faba. Genetic diversity and Fst values generally reflected the breeding system and cultivation history of the different crops. Comparisons of the diversity found in heritage varieties with that found in commercial varieties did not show a consistent pattern. Principal coordinates analysis and Unweighted Pair Group Method with Arithmetic Mean cluster analysis were used to identify four potential duplicate accession pairs.
Silvery-Thread Moss (Bryum argenteum Hedw.) is an undesirable invader of golf course putting greens across North America, establishing colonies and proliferating despite practices to suppress it. The goal was to grow genotypes of green (growing in putting greens) and native (growing in habitats outside of putting greens) B. argenteum in a common garden experiment, allowing an experimental test of life-history traits between genotypes from these two habitats. Seventeen collections of green and 17 collections of native B. argenteum were cloned to single genotypes and raised through a minimum of two asexual generations in the lab. A culture of each genotype was initiated using a single detached shoot apex and was allowed to grow for 6 mo under conditions of inorganic nutrients present and absent. Compared with genotypes from native habitats, genotypes of B. argenteum from putting greens exhibited earlier shoot regeneration and shoot induction, faster protonemal extension, longer (higher) shoots, lower production of gemmae and bulbils, and greater aerial rhizoid cover, and showed similar tendencies of chlorophyll fluorescence properties and chlorophyll content. Cultures receiving no inorganic nutrients produced less chlorophyll content, greatly reduced growth, and bleaching of shoots. Mosses from putting greens establish more quickly, grow faster, produce more abundant rhizoids, and yet do not produce as many specialized asexual propagules compared with mosses of the same species from native habitats. The highly managed putting green environment has either selected for a suite of traits that allow the moss to effectively compete with grasses, or genotypic diversity is very high in this species, allowing a set of specialized genotypes to colonize the putting green from native habitats. Successful golf course weeds have been able to adapt to this highly competitive environment by selection acting on traits or genotypes to produce plants more successful in competing with golf course grasses.
Dopaminergic imaging has high diagnostic accuracy for dementia with Lewy bodies (DLB) at the dementia stage. We report the first investigation of dopaminergic imaging at the prodromal stage.
We recruited 75 patients over 60 with mild cognitive impairment (MCI), 33 with probable MCI with Lewy body disease (MCI-LB), 15 with possible MCI-LB and 27 with MCI with Alzheimer's disease. All underwent detailed clinical, neurological and neuropsychological assessments and FP-CIT [123I-N-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl)] dopaminergic imaging. FP-CIT scans were blindly rated by a consensus panel and classified as normal or abnormal.
The sensitivity of visually rated FP-CIT imaging to detect combined possible or probable MCI-LB was 54.2% [95% confidence interval (CI) 39.2–68.6], with a specificity of 89.0% (95% CI 70.8–97.6) and a likelihood ratio for MCI-LB of 4.9, indicating that FP-CIT may be a clinically important test in MCI where any characteristic symptoms of Lewy body (LB) disease are present. The sensitivity in probable MCI-LB was 61.0% (95% CI 42.5–77.4) and in possible MCI-LB was 40.0% (95% CI 16.4–67.7).
Dopaminergic imaging had high specificity at the pre-dementia stage and gave a clinically important increase in diagnostic confidence and so should be considered in all patients with MCI who have any of the diagnostic symptoms of DLB. As expected, the sensitivity was lower in MCI-LB than in established DLB, although over 50% still had an abnormal scan. Accurate diagnosis of LB disease is important to enable early optimal treatment for LB symptoms.
Upland sheep production systems based on the utilisation of enclosed sown pastures are considered in relation to environmental constraints, recent trends in marketing requirements and a continuing need to improve economic efficiency. The need for quantitatively described decision making in relation to both the testing, development and application of new technology is discussed with particular reference to those factors influencing herbage growth, utilisation and management.
Relatively few upland farms are capable of producing marketable fat lambs before the decline in returns per kg lamb in June. Although higher returns for heavier fat or store lambs can be obtained in the autumn, the degree to which this maximizes the returns per ha will be dependent upon the stocking rate and ewe and lamb performance during the summer. It will also be dependent on the extent to which there is competition for pasture in the autumn and its effect on ewe live weight and condition during the pre-mating and post-mating period; weight and condition will affect reproductive performance which has a substantial effect on returns per ha.
The significance of sward height as a means of controlling the performance of sheep grazing sown pastures is reviewed in relation to ongoing and completed systems experiments and development projects. It is concluded that, for practical purposes, a sward height held between 3.5 and 5.5 cm will provide a sound basis for management of the lactating ewe and suckling lamb until weaning. The means of achieving sward height control in varying farming situations and the development of commercially viable management systems is considered.
In the development of systems towards improving production efficiency, a better description of responses to both level and pattern of N used is required. The need for a better understanding of responses of the ewe in terms of ovulation rate and embryo wastage to changing sward characteristics in the autumn and to the use of supplementary feeding is also required. New techniques, such as the endocrine manipulation of reproductive performance, need to be assessed in relation to existing practices and performance.
To date there have been few studies on equine personality, with many equine studies on individual differences focussing on the measurement of temperament. Personality is defined by Pervin and John (1997, ) as “Those characteristics of the person that account for consistent patterns of feeling, thinking and behaving” and is different to temperament in that it has a greater emphasis on social aspects of behaviour. Interest in this area of research has recently increased, which could be attributed to the potential implementation of personality assessment in management practices, welfare issues and potential applications in equine veterinary medicine (Mills, 1998).
Assessment of animal personality often involves using human raters to assess the personality of animals familiar to them. In order to demonstrate reliable personality data three criteria should be met, these are as follows; 1) assessments made by independent observers must agree with one another, 2) these assessments must predict behaviours and real-world outcomes and 3) observer ratings must be shown to reflect genuine attributes of the individual rated and not just the observers’ implicit theories about personality (Kenrick and Funder, 1988; Gosling and Vazire, 2002).
The accurate clinical characterisation of mild cognitive impairment (MCI) is becoming increasingly important. The aim of this study was to compare the neuropsychiatric symptoms and cognitive profile of MCI with Lewy bodies (MCI-LB) with Alzheimer's disease MCI (MCI-AD).
Participants were ⩾60 years old with MCI. Each had a thorough clinical and neuropsychological assessment and 2β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl)-nortropane single photon emission computed tomography FP-CIT SPECT). MCI-LB was diagnosed if two or more diagnostic features of dementia with Lewy bodies were present (visual hallucinations, cognitive fluctuations, motor parkinsonism, rapid eye movement sleep behaviour disorder or positive FP-CIT SPECT). A Lewy body Neuropsychiatric Supportive Symptom Count (LBNSSC) was calculated based on the presence or absence of the supportive neuropsychiatric symptoms defined by the 2017 DLB diagnostic criteria: non-visual hallucinations, delusions, anxiety, depression and apathy.
MCI-LB (n = 41) had a higher LBNSSC than MCI-AD (n = 24; 1.8 ± 1.1 v. 0.7 ± 0.9, p = 0.001). 67% of MCI-LB had two or more of those symptoms, compared with 16% of MCI-AD (Likelihood ratio = 4.2, p < 0.001). MCI-LB subjects scored lower on tests of attention, visuospatial function and verbal fluency. However, cognitive test scores alone did not accurately differentiate MCI-LB from MCI-AD.
MCI-LB is associated with neuropsychiatric symptoms and a cognitive profile similar to established DLB. This supports the concept of identifying MCI-LB based on the presence of core diagnostic features of DLB and abnormal FP-CIT SPECT imaging. The presence of supportive neuropsychiatric clinical features identified in the 2017 DLB diagnostic criteria was helpful in differentiating between MCI-LB and MCI-AD.
Using a simple absorption line model the phase dependent effects of ‘wind eclipses’ have been studied for the N IV 1718Â line in the WN4+05 binary, HD 90657. The varying strength of the absorption, as measured by the equivalent width, has been compared with the model for a range of wind parameters and assumptions. It is found that the fraction of absorbing atoms drops quickly, to the first or second power of the radius, and that a significant fraction persists beyond 60 R⊙.
A periodogram analysis of the radial velocities and absorption line strengths from IUE spectra of HD 50896 show evidence of the 3.766 day period usually associated with this star. The dominant line variations occur on time scales of ∼ 1 day but may be interpreted as higher order harmonics of the 3.766 day period.
The recent study by Caillault et al. (1985) has shown the emission-line star AS 431 (= WR 147) to be a strong X-ray source and moderately strong radio emitter. Combining optical, near-infrared and radio data, they deduced that its mass loss rate was ∼ 4 × 10−4 M⊙yr−1, an order of magnitude greater than is normal for WR stars. They also suggested that it would show up in the IRAS survey and that such data would help to elucidate whether its extreme reddening had a significant circumstellar component. To investigate this possibility and to study the general properties of the object, we have raided the IRAS Point Source Catalogue.
Ice streams provide major drainage pathways for the Antarctic ice sheet. The stress distribution and style of flow in such ice streams produce elastic and rheological anisotropy, which informs ice-flow modelling as to how ice masses respond to external changes such as global warming. Here we analyse elastic anisotropy in Rutford Ice Stream, West Antarctica, using observations of shear-wave splitting from three-component icequake seismograms to characterize ice deformation via crystal-preferred orientation. Over 110 high-quality measurements are made on 41 events recorded at five stations deployed temporarily near the ice-stream grounding line. To the best of our knowledge, this is the first well-documented observation of shear-wave splitting from Antarctic icequakes. The magnitude of the splitting ranges from 2 to 80 ms and suggests a maximum of 6% shear-wave splitting. The fast shear-wave polarization direction is roughly perpendicular to ice-flow direction. We consider three mechanisms for ice anisotropy: a cluster model (vertical transversely isotropic (VTI) model); a girdle model (horizontal transversely isotropic (HTI) model); and crack-induced anisotropy (HTI model). Based on the data, we can rule out a VTI mechanism as the sole cause of anisotropy – an HTI component is needed, which may be due to ice crystal a-axis alignment in the direction of flow or the alignment of cracks or ice films in the plane perpendicular to the flow direction. The results suggest a combination of mechanisms may be at play, which represent vertical variations in the symmetry of ice crystal anisotropy in an ice stream, as predicted by ice fabric models.
The study aim was to establish and quantify suicide risk following acute admissions for all major physical illnesses, for confirmatory purposes, from two independent information sources from different countries.
Record linkage of inpatient and death certificate data for 11 004 389 acute admissions for physical illnesses in England and 713 496 in Wales. The main outcome measure was standardised mortality ratios (SMRs) for suicide at 1 year following discharge from hospital.
There were 1781 suicides within 1 year of discharge in England (SMR = 1.7; 95% = 1.6–1.8) and 131 in Wales (SMR = 2.0; 1.7–2.3). Of 48 major physical illnesses that were associated with at least eight suicides in either country, there was high consistent suicide mortality (significant SMR >3) in both countries for constipation (SMR = 4.1 in England, 7.5 in Wales), gastritis (4.4 and 4.9) and upper gastrointestinal bleeding (3.4 and 4.5). There was high suicide mortality in one country for alcoholic liver disease, other liver disease and chronic pancreatitis; for epilepsy and Parkinson's disease; for diabetes, hypoglycaemia and hypo-osmolality & hyponatraemia; and for pneumonia, back pain and urinary tract infections.
There is little or no increased suicide mortality following acute admissions for most physical illnesses. Much of the increased suicide mortality relates to gastrointestinal disorders that are often alcohol related or specific chronic conditions, which may be linked to side effects from certain therapeutic medications. Acute hospital admissions for physical illnesses may therefore provide an opportunity for targeted suicide prevention among people with certain conditions, particularly alcohol related disorders.
The success of scaling out depends on a clear understanding of the factors that affect adoption of grain legumes and account for the dynamism of those factors across heterogeneous contexts of sub-Saharan Africa. We reviewed literature on adoption of grain legumes and other technologies in sub-Saharan Africa and other developing countries. Our review enabled us to define broad factors affecting different components of the scaling out programme of N2Africa and the scales at which those factors were important. We identified three strategies for managing those factors in the N2Africa scaling out programme: (i) testing different technologies and practices; (ii) evaluating the performance of different technologies in different contexts; and (iii) monitoring factors that are difficult to predict. We incorporated the review lessons in a design to appropriately target and evaluate technologies in multiple contexts across scales from that of the farm to whole countries. Our implementation of this design has only been partially successful because of competing reasons for selecting activity sites. Nevertheless, we observe that grain legume species have been successfully targeted for multiple biophysical environments across sub-Saharan Africa, and to social and economic contexts within countries. Rhizobium inoculant and legume specific fertiliser blends have also been targeted to specific contexts, although not in all countries. Relatively fewer input and output marketing models have been tested due to public–private partnerships, which are a key mechanism for dissemination in the N2Africa project.