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To estimate latent dietary profiles in a community-dwelling sample of older Americans and identify associations between dietary profile membership and individual demographic, socio-economic and health characteristics.
Secondary analysis of the 2012 Health and Retirement Study (HRS) and linked 2013 Health Care and Nutrition Study (HCNS). Latent profile analysis identified mutually exclusive subgroups of dietary intake and bivariate analyses examined associations between dietary profile membership, participant characteristics and nutrient intakes.
An analytic sample of 3558 adults aged 65 years or older.
Four dietary profiles were identified with 15·5 % of the sample having a ‘Healthy’ diet, 42·0 % consuming a ‘Western’ diet, 29·7 % having a diet consisting of high intake of all food groups and 12·7 % reporting relatively low intake of all food groups. Members of the ‘Healthy’ profile reported the greatest socio-economic resources and health, and members of the ‘Low Intake’ profile had the fewest resources and worst health outcomes. Macronutrient and micronutrient intakes varied across profile although inadequate and excessive intakes of selected nutrients were observed for all profiles.
We identified dietary patterns among older Americans typified by either selective intake of foods or overall quantity of foods consumed, with those described as ‘Low Intake’ reporting the fewest socio-economic resources, greatest risk of food insecurity and the worst health outcomes. Limitations including the presence of measurement error in dietary questionnaires are discussed. The causes and consequences of limited dietary intake among older Americans require further study and can be facilitated by the HRS and HCNS.
Tree-ring reconstructions of temperature often target trees at altitudinal or latitudinal tree line where annual growth is broadly expected to be limited by and respond to temperature variability. Based on this principal, regions with sparse tree line would seem to be restricted in their potential to reconstruct past temperatures. In the northeastern United States, there are only two published temperature reconstructions. Previous work in the region reconstructing moisture availability, however, has shown that using a greater diversity of species can improve reconstruction model skill. Here, we use a network of 228 tree-ring records composed of 29 species to test the hypothesis that an increase in species diversity among the pool of predictors improves reconstructions of past temperatures. Chamaecyparis thyoides alone explained 31% of the variability in observed cool-season minimum temperatures, but a multispecies model increased the explained variance to 44%. Liriodendron tulipifera, a species not previously used for temperature reconstructions, explained a similar amount of variance as Chamaecyparis thyoides (12.9% and 20.8%, respectively). Increasing the species diversity of tree proxies has the potential for improving reconstruction of paleotemperatures in regions lacking latitudinal or elevational tree lines provided that long-lived hardwood records can be located.
A power MOSFET-based push–pull configuration nanosecond-pulse generator has been designed, constructed, and characterized to permeabilize cells for biological and medical applications. The generator can deliver pulses with durations ranging from 80 ns up to 1 µs and pulse amplitudes up to 1.4 kV. The unit has been tested for in vitro experiments on a medulloblastoma cell line. Following the exposure of cells to 100, 200, and 300 ns electric field pulses, permeabilization tests were carried out, and viability tests were conducted to verify the performance of the generator. The maximum temperature rise of the biological load was also calculated based on Joule heating energy conservation and experimental validation. Our results indicate that the developed device has good capabilities to achieve well-controlled electro-manipulation in vitro.
This paper considers the timing and mechanisms of deforestation in the Western Isles of Scotland, focusing in particular on the landscape around the Calanais stone circles, one of the best preserved late Neolithic/early Bronze Age monumental landscapes in north-west Europe. We present new archaeological and palaeoenvironmental evidence from a soil and peat sequence at the site of Aird Calanais, which spans the main period of use of the Calanais circles. We then draw on a new synthesis of archaeobotanical and palynological evidence from across the Western Isles and a review of comparable data from the wider North Atlantic zone, before assessing the role of early farming communities in clearing the wooded landscapes of the region. Pollen and radiocarbon dating at the site of Aird Calanais reveal that a layer of birch branches, dating to the late Neolithic (2912–2881 cal bc), was contemporaneous with a decline in woodland at the site, as well as with the major phase of Neolithic activity at the Calanais stone circle complex. However, our synthesis of the pollen and plant macrofossil evidence from across the Western Isles suggests that the picture across these islands was altogether more complex: woodlands declined both before, as well as during, the Neolithic and deciduous woodlands remained sufficiently abundant for Neolithic fuel procurement. Finally, we consider the implications of the results for understanding the interactions between first farmers and woodlands in the wider North Atlantic region.
Oldowan sites in primary geological context are rare in the archaeological record. Here we describe the depositional environment of Oldowan occurrences at Kanjera South, Kenya, based on field descriptions and granulometric analysis. Excavations have recovered a large Oldowan artefact sample as well as the oldest substantial sample of archaeological fauna. The deposits at Kanjera South consist of 30 m of fluvial, colluvial and lacustrine sediments. Magneto- and biostratigraphy indicate the Kanjera South Member of the Kanjera Formation was deposited during 2.3–1.92 Ma, with 2.0 Ma being a likely age for the archaeological occurrences. Oldowan artefacts and associated fauna were deposited in the colluvial and alluvial silts and sands of beds KS1–3, in the margins of a lake basin. Field descriptions and granulometric analysis of the sediment fine fraction indicate that sediments from within the main archaeological horizon were emplaced as a combination of tractional and hyperconcentrated flows with limited evidence of debris-flow deposition. This style of deposition is unlikely to significantly erode or disturb the underlying surface, and therefore promotes preservation of surface archaeological accumulations. Hominins were repeatedly attracted to the site locale, and rapid sedimentation, minimal bone weathering and an absence of bone or artefact rounding further indicate that fossils and artefacts were quickly buried.
The Pueblo population of Chaco Canyon during the Bonito Phase (AD 800–1130) employed agricultural strategies and water-management systems to enhance food cultivation in this unpredictable environment. Scepticism concerning the timing and effectiveness of this system, however, remains common. Using optically stimulated luminescence dating of sediments and LiDAR imaging, the authors located Bonito Phase canal features at the far west end of the canyon. Additional ED-XRF and strontium isotope (87Sr/86Sr) analyses confirm the diversion of waters from multiple sources during Chaco’s occupation. The extent of this water-management system raises new questions about social organisation and the role of ritual in facilitating responses to environmental unpredictability.
Introduction: Optimal discharge communication between healthcare providers and parents who present to the emergency department (ED) with their children is not well understood. Current research regarding discharge communication is equivocal and predominantly focused on evaluating different delivery formats or strategies with little attention given to communication behaviours or the context in which the communication occurs. The objective of this study was to characterize the process and structure of discharge communication in a pediatric ED context. Methods: Real-time video observation and follow-up surveys were used in two academic pediatric EDs in Canada. Parents who presented with their child to the ED with one of six illness presentations, a Canadian Triage Acuity Score of 3-5 were eligible to participate. All ED physicians, learners, and staff members were also eligible. Provider-parent communication was analyzed using the Roter Interaction Analysis System (RIAS) to code each utterance. Parent health literacy and anxiety were measured upon admission to the ED. Parent recall of important discharge information and satisfaction with communication was assessed within 72 hours of discharge. Results: A total of 107 ED patient visits were video recorded and a total of 70,000 utterances were coded across six illness presentations: abdominal pain (n=23), asthma (n=7), bronchiolitis (n=4), diarrhea/vomiting (n=20), fever (n=27), and minor head injury (n=26). The average length of stay for participants was 3 hours, with an average of three provider interactions per visit. Interactions ranged in time from less than one minute up to 29 minutes, with an average of six minutes per interaction. The majority of visits were first episodes for the presenting illness (63.2%). Physician utterances coded most commonly involved giving medical information (22.9%), whereas nurses most commonly gave orientation instructions (20.9%). Learners were most likely to employ active listening techniques (14.2%). Communication that provided post-discharge instructions for parents comprised 8.5% of all utterances. Overall, providers infrequently assessed parental understanding of information (2.0%). Only 26% of parents recalled receiving important discharge information deemed relevant to their childs disposition. Yet, parent satisfaction with the amount of information communicated during the ED visit was generally high (89.6% agreed or strongly agreed). Conclusion: This is the first study of ED discharge communication to be conducted in a pediatric setting using video observation methods. Provider-parent communication was predominantly characterized by giving medical information, with little time devoted to preparing families to care for their child at home. Greater assessment of parent comprehension of discharge communication is needed to ensure that parents understand important instructions and know when to seek further care.
Avifaunal remains from archaeological sites have a largely unrecognized explanatory potential. Archaeological, ethnohistoric, and ethnographic records have shown that, especially in Mesoamerica, birds and their products have served a wide range of utilitarian, decorative, and symbolic purposes. Despite their ability to inform research on many aspects of prehistoric life, avifaunal remains from archaeological contexts remain under-studied. This paper demonstrates how a holistic approach to their analysis—one that explores several types of human-bird interaction—can move beyond studies of subsistence. A previously reported and newly updated avifaunal collection was reanalyzed to shed light on the relationship between the many uses of birds and the establishment of hereditary inequality at Paso de la Amada, an Early Formative period ceremonial center on the Pacific coast of Chiapas, Mexico. Results indicate that Early Formative people used birds as a source of food, feathers, and bone, and that the ritual use of birds was an important component of status display. Even at this early date, birds were symbolically valuable and played a role in ritual performance, suggesting that their later significance in Mesoamerican ritual, religion, and iconography has an antecedent beginning no later than 1700 BC.
The relations between genetic change in domestic livestock and infectious disease (including both its epidemiology and the animal's reaction to it) are examined. The overall picture is confusing because there are different, and seemingly unrelated, ways of considering the issue. An attempt is made to put these together into a more general framework. Four processes of particular interest are distinguished and discussed in more detail: (i) the way a population's genetic potential for immunocompetence can be changed by breeding, (ii) the way an animal's immunocompetence is influenced by that animal's production potential, in combination with the environmental resources that are available to it at a given time, (iii) the way the disease status of an animal (and a population of animals) is influenced by its immunocompetence, and (iv) the way the production level of an animal is influenced by activation of its immune system. Ultimately, all four processes influence the realised level of production.
This comes down to four questions that need to be addressed: (i) can we use genetic variation in immunocompetence in animal breeding? (ii) does a higher production potential (today's direction of breeding) have a negative impact on immunocompetence? (iii) does improved immunocompetence result in improved health? and (iv) how large is the negative impact of disease on production?
In nutritional terms productivity in dairy cows is best expressed in multiples of their energy requirements for maintenance, which is directly related to Metabolic Body Weight (MBW). Energy requirements can further be specified as those for free energy (fME), ketogenic energy (kME), glucogenic energy (gME) and aminogenic energy (aME). For maintenance, energy is required in an approximate ratio fME:gME:aME of 85:5:10.For a production level of 6x maintenance the required ratio of fME:kME:gME:aME is approximately 18:31:29:22, hence 70% of the required ME has to be delivered as specific nutrients.
During their productive life, dairy cattle alternate periods with high and periods with low risk of an inadequate nutrient supply. A period of high risk is between 10 days pre-partum and 90 days postpartum. High risk in this period means a high susceptibility for metabolic and reproductive disorders, many of which are interrelated. Negative Energy Balance (NEB) in early lactation is a metabolic status that is almost inevitable in high yielding dairy cows. In severe cases this is an important predisposing factor for metabolic disorders (paturient paresis, fatty liver, ketosis, displaced abomasum) and reproductive disorders (undetected heat, delayed ovarian cycle, reduced fertility, increased between calving interval).
Adequate nutrient supply is required from 2 weeks pre-partum onwards. Critical issues are energy density, distribution between structural and non-structural carbohydrates and distribution between fME, kME, gME and aME. Practical solutions, which can help alleviate the metabolic and reproductive problems, could be a nutrient based feed evaluation system, a lower peak yield combined with an improved persistence and maybe a deliberately increased calving interval.
In commercial egg type chicken breeding three and four way crosses are used to produce commercial layers. The primary breeders are using closed nucleus breeding programmes, with birds kept under maximum biosecurity. All grand parents and parents are produced from a closed nucleus for the world wide demand of commercial layers. The breeding goals have been focused for several decades on increasing number of eggs per hen housed. Additional traits have become more important during the last decade, i.e. feed efficiency, internal and external egg quality and general adaptability. Prior to each selection, weights for individual traits within the selection index are adjusted to meet market demands. Breeding stock and commercial layers have to be bred to perform adequately in a variety of systems ranging from large intensive cage units to free range management under different environmental conditions world-wide.
Despite intensive selection for egg production the decrease in genetic variation observed in closed commercial lines is not yet critical. Peak production is approaching the biological limit of one egg a day. During this period genetic and phenotypic variation have been significantly reduced. But for early production (sexual maturity) and late production (persistency) genetic variation is still high. In a mating scheme avoiding full and half sib matings no serious inbreeding depression is observed. To achieve continued future genetic progress, selection pressure will shift to other traits like internal and external egg quality and perhaps behaviour traits which still respond to selection.
Primary breeders are responding to this challenge by testing pedigreed cross-line hens in a wide range of environments and housing systems while the pure-line elite stock is kept under conditions of maximum biosecurity. Marker assisted selection is already part of commercial breeding programmes. In the past, blood typing has been used to improve Marek's resistance, whereas today anonymous microsatellites which are linked to traits of economic interest are used for selection. In particular, selection between full sib males can give a major improvement.
The whole industry is getting more specialised. While the genetic potential of the birds is improved management and nutrition have also to be adapted to changing demands. The general goal for the future is to breed chickens with the ability to function well within a wider range of production conditions and do not respond to the slightest stress.
Broiler breeders conduct their breeding programs only in optimal environments, claiming that because farmers are instructed to provide the broilers with optimal management, genotype by environment interactions (GxE) are not important for the broiler industry. However, with the rapid development of the poultry industry worldwide, high-performance broiler stocks are now being imported to developing countries where environmental control, mainly the mitigation of hot climates, is not feasible. Moreover, results from several studies suggest that due to the increase in genetic potential for rapid growth rate, resulting from successful breeding programs, broilers are becoming more sensitive to rather small environmental deviations from optimal conditions (Leenstra and Cahaner, 1991; Cahaner and Leenstra, 1992; Cahaner et al., 1993; Settar et al., 1999; Yunis et al, 1999). Hence, also in developed countries, many broilers will be, or are already being reared under suboptimal hot environments.
Selective breeding has been an important component in the increased output and efficiency of animal production since the 1950's. At the same time there has been increasing moral concern over the welfare of modern farmed animals with much of the focus on the environment and management of farm animals and relatively little consideration of the impact of genetic change on welfare. This is now changing, partly because of some well-publicised examples where selection has led to ‘undesirable’ side effects, and because of the perceived welfare risk of emerging biotechnologies. This paper will address whether and how moral concerns over animal welfare should place limitations on genetic change in animal production.
The major ruminant species, dairy and beef cattle and sheep, represent a rather heterogeneous group as regards genetic improvement, which to a large extent reflects their respective breeding structures. In the UK, the beef cattle and sheep industries still span many different breeds, have small herds/flocks, and have been relatively unaffected by agribusiness investment, and are assumed to have a traditional pyramid breeding structure, in which progress is determined by a small number of breeders. Recording of production information, which to date has focussed on terminal sire characteristics, is relatively recent, and until the use of across herd evaluations, genetic progress was probably limited. However in recent years there have been gains in both growth and muscling. There is little evidence or concern for undesired consequences in commercial flocks, partly because of the extensive use of crossbreeding in these industries, which exploits both breed complementarity and heterosis.
By contrast, the dairy industry is now dominated by purebred Holsteins. Increasingly breeding activities are both global in scope and dominated by a small number of large breeding companies. Because most traits of interest are only expressed in the female, improvement programmes have continued to focus on progeny testing, with test daughters in many herds. Most recording schemes and promotional activities emphasise production and type traits. The dairy industry is also notable for the publication of bull progeny test results, so that top bulls can then be used as sires of the next generation of by all companies. These bull evaluations now extend to international rankings.
Data from the US indicates continuing genetic progress for production traits in the Holstein, particularly since the 1960s, by when progeny testing had been established, frozen semen widely used, and adequate statistical procedures in place for evaluating bulls. Genetic progress is also evident for type traits. There is now growing concern and evidence of undesirable genetic changes in fertility, disease incidence and overall stress, despite improved nutrition and general management. Altering this situation will require both the recording of such traits and the use of that information by breeding companies, especially in sire selection.
The poultry meat industry, in continual pursuit of improved efficiency, has demanded rapid growth rate. Primary breeding companies have responded to industry pressure and growth rate has increased in an almost linear fashion. Despite the obvious advantages to industry profitability, it can be argued that increased growth has placed more emphasis on the demand tissues of growth than those systems or organs that supply the substrates for rapid growth and/or are essential to support the increase in body mass. One of the consequences is that modern broilers are not as adaptable to their environments as their predecessors were. Rapid growth has also produced problems not seen in slower growing birds. Skeletal and cardiovascular disease (sudden death syndrome (SDS), ascites) are examples of growth related problems. Although it can not be said that rapid growth automatically will result in these problems, there is no doubt that the!re is a relationship.
Genetic progress in poultry species for meat production has contributed to the consistent growth in world production of poultry meat. The poultry species have a number of advantages over the larger species used for meat production. It is possible to maintain large pedigreed populations and use their high reproductive rates to transfer genetic progress to the production generations in less than five years. These populations continue to maintain high heritabilities despite, in some cases, prolonged selection. The history of selection progress in broiler chickens (Gallus gallus domesticus) is reviewed and compared with rates of progress in the duck (Anas platyrhyncos) and the turkey (Meleagris gallopavo).
The rates of genetic change for production traits such as growth, feed efficiency and yield have changed the physiology of the birds. Changes in selection criteria have been made to improve the robustness of the production stock. This allows them to perform well in a wider range of environments. These have been combined with improved definitions of the optimum environments for the birds to minimise any impact on welfare and health. This paper describes examples of selection in the broiler chicken aimed at improving skeletal quality and resistance to ascites. A number of the factors influencing future selection criteria are discussed. Breeding programmes have adapted to respond quickly to adverse genetic correlated responses. The need to combine selection for a large number of traits requires that the programmes are very efficient and use the best statistical techniques available for multivariate breeding value estimation.