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The current study examined whether self-reported memory problems among cognitively intact older adults changed concurrently with, preceded, or followed depressive symptoms over time.
Data were collected annually via in-person comprehensive medical and neuropsychological examinations as part of the Einstein Aging Study.
Community-dwelling older adults in an urban, multi-ethnic area of New York City were interviewed.
The current study included a total of 1,162 older adults (Mage = 77.65, SD = 5.03, 63.39% female; 74.12% White). Data were utilized from up to 11 annual waves per participant.
Multilevel modeling tested concurrent and lagged associations between three types of memory self-report (frequency of memory problems, perceived one-year decline, and perceived ten-year decline) and depressive symptoms.
Results showed that self-reported frequency of memory problems covaried with depressive symptoms only in participants who were older at baseline. Changes in perceived one-year and ten-year memory decline were related to changes in depressive symptoms across all ages. Depressive symptoms increased the likelihood of perceived ten-year memory decline the next year; however, perceived ten-year memory decline did not predict future depressive symptoms. Additionally, no significant temporal relationship was observed between depressive symptoms and self-reported frequency of memory problems or perceived one-year memory decline.
Our findings highlight the importance of testing the unique associations of different types of self-reported memory problems with depressive symptoms.
Scrapie is a transmissible spongiform encephalopathy (TSE) and belongs to a category of incurable diseases that include BSE in cattle. An association exists between the Prion-Protein (PrP) genotype of an animal and the risk of developing disease after exposure (Tongue et al., 2004). This PrP genetic information is the basis of the National Scrapie Plan (NSP) which aims, through genotyping, to eradicate those individuals which have the susceptible alleles. Studies into scrapie risk (Jeffrey et al., 2002) have highlighted several alleles which confer scrapie susceptibility. The NSP have used these alleles to categorise individuals according to risk with group one being most scrapie resistant to group five being least resistant. VRQ alleles are synonymous with infection however the ARQ affords susceptibility but not the disease itself. Genotype may however not be the sole indicator of scrapie risk. There is an inference of a relationship between phenotypic characteristics (hornedness, coat colour) and scrapie risk. These alternative indicators of scrapie risk may affect the final choice of susceptible individuals. Scrapie risk studies carried out on the Shetland Isles (Jeffrey et al., 2002) investigated the alleles concerned with scrapie infection. Results confirmed that VRQ alleles are synonymous with scrapie infection however the ARQ alleles, even though they afford susceptibility, do not necessarily confer disease, the animal still has to be exposed to the scrapie agent. Using survey-type questionnaires, the study investigated any potential relationship between the PrP gene, coat colour and hornedness.
Interpretation of ice mass elevation changes observed by satellite altimetry demands quantification of the proportion of elevation change which is attributable to variations in firn densification. Detailed stratigraphic logging of snowpack structure and density was carried out at ~1km intervals along a 47 km transect on Devon Ice Cap, Canada, in spring (pre-melt) and autumn (during/ after melt) 2004 and 2006 to characterize seasonal snowpack variability across the full range of snow facies. Simultaneous meteorological measurements were gathered. Spring (pre-melt) snowpacks show low variability over large spatial scales, with low-magnitude changes in density. The end-of-summer/ autumn density profiles show high variability in both 2004 and 2006, with vastly different melt regimes generating dissimilar patterns of ice-layer formation over the two melt seasons. Dye-tracing experiments from spring to autumn 2006 reveal that vertical and horizontal distribution of meltwater flow within and below the annual snowpack is strongly affected by the pre-existing, often subtle stratigraphic interfaces in the snowpack, rather than its bulk properties. Strong interannual variability suggests that using a simple relationship between air temperature, elevation and snowpack densification to derive mass change from measurements of elevation change across High Arctic ice caps may be misguided. Melt timing and duration are important extrinsic factors governing snowpack densification and ice-layer formation in summer, rather than averaged air temperatures.
We present low-frequency spectral energy distributions of 60 known radio pulsars observed with the Murchison Widefield Array telescope. We searched the GaLactic and Extragalactic All-sky Murchison Widefield Array survey images for 200-MHz continuum radio emission at the position of all pulsars in the Australia Telescope National Facility (ATNF) pulsar catalogue. For the 60 confirmed detections, we have measured flux densities in 20 × 8 MHz bands between 72 and 231 MHz. We compare our results to existing measurements and show that the Murchison Widefield Array flux densities are in good agreement.
In 1988, a Joint Commission (9 and 25) meeting on the causes of the well-known limitations on the precision of infrared astronomy led to several suggestions to improve matters (see Milone 1989). These included better reporting of the photometric systems in use by practitioners, redesign of the infrared passbands to be more optimally placed inside the atmospheric windows, and development of a method to ascertain the water vapor content of the atmosphere when the astronomical infrared measurements were being made. An Infrared Astronomy Working Group was formed to look into the matter. Advice and suggestions were solicited from the community at large. All who volunteered information became, de facto, members of the Working Group. A small subgroup composed of Andrew Young, Chris Stagg, and Milone set to work on the central of the recommendations: improvement of the passbands. Young, Milone, k Stagg (1994) (hereafter YMS) summarized the work: existing JHKLMN and Q infrared passbands were found to be both far from standardized, and all too frequently defined, to various degrees, by the water vapor and other components of the terrestrial atmosphere. Following extensive numerical simulations with a MODTRAN 3 terrestrial-atmospheres model package, and Kurucz stellar atmospheres, we suggested a set of improved infrared passbands designed explicitly to fit within, and not be defined by, the terrestrial atmospheric windows; however, we sought to optimize them so as to get the maximum throughput consistent with plausible limitations on precision of manufacture of the filters. In 1995 and again in 1997, a number of improvements were made in the code with which the improved passbands were designed. While they do not much affect the optimization trials and thus the passband recommendations, they have been used to extend the modeling.
Determining the internal layout of archaeological structures and their uses has always been challenging, particularly in timber-framed or earthen-walled buildings where doorways and divisions are difficult to trace. In temperate conditions, soil-formation processes may hold the key to understanding how buildings were used. The abandoned Roman town of Silchester, UK, provides a case study for testing a new approach that combines experimental archaeology and micromorphology. The results show that this technique can provide clarity to previously uncertain features of urban architecture.
Supervised injectable heroin (SIH) treatment has emerged over the past 15 years as an intensive treatment for entrenched heroin users who have not responded to standard treatments such as oral methadone maintenance treatment (MMT) or residential rehabilitation.
To synthesise published findings for treatment with SIH for refractory heroin-dependence through systematic review and meta-analysis, and to examine the political and scientific response to these findings.
Randomised controlled trials (RCTs) of SIH treatment were identified through database searching, and random effects pooled efficacy was estimated for SIH treatment. Methodological quality was assessed according to criteria set out by the Cochrane Collaboration.
Six RCTs met the inclusion criteria for analysis. Across the trials, SIH treatment improved treatment outcome, i.e. greater reduction in the use of illicit ‘street’ heroin in patients receiving SIH treatment compared with control groups (most often receiving MMT).
SIH is found to be an effective way of treating heroin dependence refractory to standard treatment. SIH may be less safe than MMT and therefore requires more clinical attention to manage greater safety issues. This intensive intervention is for a patient population previously considered unresponsive to treatment. Inclusion of this low-volume, high-intensity treatment can now improve the impact of comprehensive healthcare provision.
We present the results of an approximately 6 100 deg2 104–196 MHz radio sky survey performed with the Murchison Widefield Array during instrument commissioning between 2012 September and 2012 December: the MWACS. The data were taken as meridian drift scans with two different 32-antenna sub-arrays that were available during the commissioning period. The survey covers approximately 20.5 h < RA < 8.5 h, − 58° < Dec < −14°over three frequency bands centred on 119, 150 and 180 MHz, with image resolutions of 6–3 arcmin. The catalogue has 3 arcmin angular resolution and a typical noise level of 40 mJy beam− 1, with reduced sensitivity near the field boundaries and bright sources. We describe the data reduction strategy, based upon mosaicked snapshots, flux density calibration, and source-finding method. We present a catalogue of flux density and spectral index measurements for 14 110 sources, extracted from the mosaic, 1 247 of which are sub-components of complexes of sources.
Recent years have seen a shift of archaeological focus away from the confines of the individual site and towards broader issues of land-use and landscape history. Hence a need for archaeological and palaeoenvironmental evidence which tells us about the area utilized from sites rather than about the environment on the site itself. Valley sediments are one possible source of this evidence and this paper considers their potential with specific reference to sediments in chalkland valleys on the South Downs. It also attempts to confront some more specific problems of landscape history. One aim was to assess the extent of erosion and valley sediments within defined study areas and to establish to what extent climatic and land-use factors were responsible for changes in the pattern of sedimentation. It was also hoped that detailed work on land-use sequences would provide a framework for considering long-term settlement trends on the chalk. Why, for instance, do we have dense concentrations of archaeological sites on land which is today somewhat marginal, and how were the valley bottoms utilized in prehistory?
The triennial meeting of Commission 4 was attended by 16 people. All of the presentations from the meeting are provided on the commission website at http://www.iaucom4.org/c4docs.html, so this report provides only summaries.
In the lead-up to the Square Kilometre Array (SKA) project, several next-generation radio telescopes and upgrades are already being built around the world. These include APERTIF (The Netherlands), ASKAP (Australia), e-MERLIN (UK), VLA (USA), e-EVN (based in Europe), LOFAR (The Netherlands), MeerKAT (South Africa), and the Murchison Widefield Array. Each of these new instruments has different strengths, and coordination of surveys between them can help maximise the science from each of them. A radio continuum survey is being planned on each of them with the primary science objective of understanding the formation and evolution of galaxies over cosmic time, and the cosmological parameters and large-scale structures which drive it. In pursuit of this objective, the different teams are developing a variety of new techniques, and refining existing ones. To achieve these exciting scientific goals, many technical challenges must be addressed by the survey instruments. Given the limited resources of the global radio-astronomical community, it is essential that we pool our skills and knowledge. We do not have sufficient resources to enjoy the luxury of re-inventing wheels. We face significant challenges in calibration, imaging, source extraction and measurement, classification and cross-identification, redshift determination, stacking, and data-intensive research. As these instruments extend the observational parameters, we will face further unexpected challenges in calibration, imaging, and interpretation. If we are to realise the full scientific potential of these expensive instruments, it is essential that we devote enough resources and careful study to understanding the instrumental effects and how they will affect the data. We have established an SKA Radio Continuum Survey working group, whose prime role is to maximise science from these instruments by ensuring we share resources and expertise across the projects. Here we describe these projects, their science goals, and the technical challenges which are being addressed to maximise the science return.
The Australian Square Kilometre Array Pathfinder (ASKAP) will give us an unprecedented opportunity to investigate the transient sky at radio wavelengths. In this paper we present VAST, an ASKAP survey for Variables and Slow Transients. VAST will exploit the wide-field survey capabilities of ASKAP to enable the discovery and investigation of variable and transient phenomena from the local to the cosmological, including flare stars, intermittent pulsars, X-ray binaries, magnetars, extreme scattering events, interstellar scintillation, radio supernovae, and orphan afterglows of gamma-ray bursts. In addition, it will allow us to probe unexplored regions of parameter space where new classes of transient sources may be detected. In this paper we review the known radio transient and variable populations and the current results from blind radio surveys. We outline a comprehensive program based on a multi-tiered survey strategy to characterise the radio transient sky through detection and monitoring of transient and variable sources on the ASKAP imaging timescales of 5 s and greater. We also present an analysis of the expected source populations that we will be able to detect with VAST.
The population-based Northern Survey of Twin and Multiple Pregnancy (NorSTAMP, formerly the Multiple Pregnancy Register) has collected data since 1998 on all multiple pregnancies in North of England (UK) from the earliest point of ascertainment in pregnancy. This paper updates recent developments to the NorSTAMP and presents some early mortality data from the first 10 years of data collection (1998–2007). Since 2005, mothers have been asked to give explicit consent for their identifiable data to be held by the survey, in line with changing guidance and legal frameworks for identifiable data. In 2009, regional standards of care for multiple pregnancies were developed, agreed, and disseminated. During 1998–2007, 4,865 twin maternities (pregnancies with at least one live birth or stillbirth) were registered, with an average twinning rate of 14.9 per 1,000 maternities. The overall stillbirth and neonatal mortality rates in twins were 18.0/1,000 births and 23.0/1,000 live births respectively. Stillbirth and neonatal mortality rates were significantly higher in monochorionic than dichorionic twins: 44.4 versus 12.2 per 1,000 births (relative risk [RR] 3.6, 95% Confidence Intervals [CI] 2.6–5.1), and 32.4 versus 21.4 per 1,000 live births (RR 1.5, 95% CI 1.04–2.2) respectively. There was no significant improvement during this period in either stillbirth or neonatal mortality rates in either chorionicity group. This population-based survey is an important source of data on multiple pregnancies, which allows monitoring of trends in multiple birth rates and pregnancy losses, providing essential information to support improvements in clinical care and for epidemiological research.
The central proposition of Toby Pillatt is that in developing an understanding of past human affairs weather is as important as, or more so than, climate. Climate may be simply defined as average weather, whilst weather is the day-to-day occurrence of atmospheric phenomena which impact in perceptible ways on people's lives. The general proposition is sound enough; the challenges come in implementing these ideas in ways which advance our understanding of past people–environment relationships.
Dietary fatty acid supply can affect stress response in fish during early development. Although knowledge on the mechanisms involved in fatty acid regulation of stress tolerance is scarce, it has often been hypothesised that eicosanoid profiles can influence cortisol production. Genomic cortisol actions are mediated by cytosolic receptors which may respond to cellular fatty acid signalling. An experiment was designed to test the effects of feeding gilthead sea-bream larvae with four microdiets, containing graded arachidonic acid (ARA) levels (0·4, 0·8, 1·5 and 3·0 %), on the expression of genes involved in stress response (steroidogenic acute regulatory protein, glucocorticoid receptor and phosphoenolpyruvate carboxykinase), lipid and, particularly, eicosanoid metabolism (hormone-sensitive lipase, PPARα, phospholipase A2, cyclo-oxygenase-2 and 5-lipoxygenase), as determined by real-time quantitative PCR. Fish fatty acid phenotypes reflected dietary fatty acid profiles. Growth performance, survival after acute stress and similar whole-body basal cortisol levels suggested that sea-bream larvae could tolerate a wide range of dietary ARA levels. Transcription of all genes analysed was significantly reduced at dietary ARA levels above 0·4 %. Nonetheless, despite practical suppression of phospholipase A2 transcription, higher leukotriene B4 levels were detected in larvae fed 3·0 % ARA, whereas a similar trend was observed regarding PGE2 production. The present study demonstrates that adaptation to a wide range of dietary ARA levels in gilthead sea-bream larvae involves the modulation of the expression of genes related to eicosanoid synthesis, lipid metabolism and stress response. The roles of ARA, other polyunsaturates and eicosanoids as signals in this process are discussed.