2,591 research outputs found

    Exclusive breastfeeding duration and infant infection

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    BACKGROUND/OBJECTIVES: We estimated the risk of infection associated with the duration of exclusive breastfeeding (EBF). SUBJECT/METHODS: We analysed the data on 15 809 term, singleton infants from the UK Millennium Cohort Study. Infants were grouped according to months of EBF: never, <2, 2-4, 4-6 and 6 (the latter being World Health Organisation (WHO) policy since 2001: 'post-2001 WHO policy'). Among those EBF for 4-6 months, we separated those who started solids, but not formula, before 6 months, and were still breastfeeding at 6 months (that is, WHO policy before 2001: 'pre-2001 WHO policy'), from other patterns. Outcomes were infection in infancy (chest, diarrhoeal and ear). RESULTS: EBF was not associated with the ear infection, but was associated with chest infection and diarrhoea. EBF for <4 months was associated with a significantly increased risk of chest infection (adjusted risk ratios (RR) 1.24-1.28) and diarrhoea (adjusted RRs 1.42-1.66) compared with the pre-2001 WHO policy. There was an excess risk of the chest infection (adjusted RR 1.19, 95% confidence interval (CI): 0.97-1.46) and diarrhoea (adjusted RR 1.66, 95% CI: 1.11, 2.47) among infants EBF for 4-6 months, but who stopped breastfeeding by 6 months, compared with the pre-2001 WHO policy. There was no significant difference in the risk of chest infection or diarrhoea in those fed according to the pre-2001 versus post-2001 WHO policy. CONCLUSIONS: There is an increased risk of infection in infants EBF for <4 months or EBF for 4-6 months who stop breastfeeding by 6 months. These results support current guidelines of EBF for either 4-6 or 6 months, with continued breastfeeding thereafter.European Journal of Clinical Nutrition advance online publication, 27 July 2016; doi:10.1038/ejcn.2016.135

    Ecological determinants of roe deer (Capreolus capreolus) spatial behavior and movement in limiting conditions

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    For the majority of large ungulates living in temperate regions winter is the limiting season, because of the combined effects of lack of resource availability and severity of climatic conditions. Those species that did not develop any particular morphological and physiological adaptation to cope with winter severity may adopt movement and space use tactics instead (like e.g. migration). Specifically, these space use patterns may emerge at different spatiotemporal scales to allow individuals to accede the resources they need and escape unfavourable conditions, thus determining both individual fate and population dynamics. A detailed understanding of the relationship between limiting factors in wintertime, and individual movement response, is remarkable to preserve and manage wildlife successfully, especially in the context of fast-occurring climate change that induces important alterations in landscape and resource distribution (e.g. changes of snow cover patterns). The comparison of movement tactics under different environmental scenarios, e.g. by means of large -scale analysis at the species distribution range, represents a valuable approach to work in that direction and to assess the effects of landscape alteration on individual movement. Roe deer (Capreolus capreolus) is an excellent model species to investigate these issues, because its distribution range covers most of Europe, thanks to its high ecological plasticity. For those populations that live in northern and mountain environments, winter is the limiting season because roe deer lack any morphological and physiological adaptations to cope with winter severity. In spite of the adoption of specific movement tactics such as partial migration from summer to winter ranges, roe deer may still face limiting conditions in some areas of the distribution range exposed to winter severity. Wildlife managers therefore have developed supplemental feeding programs to sustain roe deer (and other ungulate) populations. Regardless of the pervasiveness of this practice and the potential negative ecological consequences (such as for example the enhanced probability of disease transmission), if and how the interplay between distribution of supplemental feeding sites and winter severity may shape roe deer spatial ecology remains mostly unknown. During my PhD, I provided a contribution to investigate in this direction. First, I relied on the data stored and managed in the EURODEER database (www.eurodeer.org) to evaluate across a wide latitudinal and altitudinal gradient how individuals responded to the presence of these patchily distributed resources under different environmental conditions and supplemental feeding management. The comprehensiveness of large scale datasets such as EURODEER is counterbalanced by some limitations in terms of data resolution of some potentially meaningful environmental variables, such as snow cover. To overcome these limitations, I empirically collected accurate data on snow cover and snow sinking-depth to assess the combined effect of snow and of the distribution of feeding stations on winter resource selection in an Alpine population of roe deer. The investigation of the effect of feeding stations on individual space use tactics should go hand in hand with a proper assessment of the inter-individual relationships occurring at feeding stations, which in turn correspond to contacts btween animals. Measurements of contact rates is a relatively new ecological interest, and could be performed either by visual recording of observers, or by means of proximity loggers or, as alternative, using tr acking data that permit to infer spatial relationships from individual trajectories. The latter two approaches are more practical in terms of application, but both need to be carefully calibrated to avoid biased ecological inference derived from the obtained contact measurements. In this context, I performed a detailed analysis and modelling of the factors influencing the connectivity of recently introduced proximity loggers (WSN, Wireless Sensor Network). In parallel, I explored the potential applicability of SECONDO spatiotemporal database for the investigation of spatial relationships among individuals through the more widespread GPS tracking data. The large-scale comparative analyses I conducted along a wide latitudinal and altitudinal gradient showed that the use of feeding sites by roe deer is highly seasonal, and specifically associated to low temperatures and activation of the feeding stations, but not to snow cover. Moreover, I found some indications that winter use of feeding stations was negatively affected by the presence of competitors. Finally, I found a strong signal of the reduction of individual home range size in relation to feeding site use. Local assessment of roe deer winter resource selection partially supported these results: the main drivers of roe deer resource selection included the proximity to feeding stations (although to a lesser extent than expected) and, a more strong inverse relationship with snow sinkng depth. The main driver of roe deer habitat use was presence of forest canopy. The absence of any statistically significant effect of the index used for measuring snow at a large scale (MODIS) supported the importance of local measurements of snow to complement remotely-sensed data. The finding that the use of feeding stations leads individuals to concentrate their movements around these sites supports the hypothesis of high contact rate between individuals at feeding sites. i.e. as they would work as attractive points. The assessment of encounters is preliminary to the evaluation of such hypothesis. I have demonstrated Wireless Sensor Network proximity loggers as tools with high potentiality for assessment of encounters. At the same time, my work has strongly indicated the need to carefully calibrate these tools before applying them for any biological investigation, and provided practical guidelines on how to proceed, including how to model the error probability. Alternatively, I laid the first technical premises to assess encounters from the more widespread GPS tracking data, by means of high-performance queries within an appropriate spatiotemporal database. I conclude that roe deer use feeding stations, but only when winter conditions are particularly harsh (i.e. low temperature, abundant snow cover). In a context of climate change with an alteration of snow pattern distribution due to a general increase of temperatures, it would be essential to understand whether supplemental feeding management will still be a reasonable and effective tool to manage roe deer. More generally, it would be necessary to assess whether roe deer indeed need feeding stations for overwinter survival. This work clearly provides evidence that the distribution of feeding stations modifies roe deer spatial behaviour. A full understanding of the patterns of animal aggregation, derived from the correct measurement of contact rates, is thus fundamental to understand the consequences of supplemental feeding practices on animal welfare, and ecosystem consequences (e.g., disease transmission). Research in these directions would ultimately permit to understand the tradeoff between benefits and costs, both for wildlife, and as a human action, of supplemental feeding practices, thus helping wildlife managers to take the right decisions

    The effects of a tea tree oil-containing gel on plaque and chronic gingivitis

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    The document attached has been archived with permission from the Australian Dental Association. An external link to the publisher’s copy is included.Background: This clinical study assessed the effects of topically applied tea tree oil (TTO)-containing gel on dental plaque and chronic gingivitis. Methods: This was a double-blind, longitudinal, non-crossover study in 49 medically fit non-smokers (24 males and 25 females) aged 18–60 years with severe chronic gingivitis. Subjects were randomly assigned to three groups and given either TTO-gel (2.5 per cent), chlorhexidine (CHX) gel (0.2 per cent), or a placebo gel to apply with a toothbrush twice daily. Treatment effects were assessed using the Gingival Index (GI), Papillary Bleeding Index (PBI) and plaque staining score (PSS) at four and eight weeks. Results: No adverse reactions to any of the gels were reported. The data were separated into subsets by tooth (anterior and posterior) and tooth surface (buccal and lingual). The TTO group had significant reduction in PBI and GI scores. However, TTO did not reduce plaque scores, which tended to increase over the latter weeks of the study period. Conclusion: Although further studies are required, the anti-inflammatory properties of TTO-containing gel applied topically to inflamed gingival tissues may prove to be a useful non-toxic adjunct to chemotherapeutic periodontal therapy.S Soukoulis and R Hirsc

    d dimensional SO(d)-Higgs Models with Instanton and Sphaleron: d=2,3

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    The Abelian Higgs model and the Georgi-Glashow model in 2 and 3 Euclidean dimensions respectively, support both finite size instantons and sphalerons. The instantons are the familiar Nielsen-Oleson vortices and the 't Hooft-Polyakov monopole solutions respectively. We have constructed the sphaleron solutions and calculated the Chern-Simons charges N_cs for sphalerons of both models and have constructed two types of noncontractible loops between topologically distinct vacuua. In the 3 dimensional model, the sphaleron and the vacuua have zero magnetic and electric flux while the configurations on the loops have non vanishing magnetic flux.Comment: 24 pages, 3 figures, LaTe

    Differential metabolism of deoxyribonucleosides by leukaemic T cells of immature and mature phenotype

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    Experimental evidence has indicated that T lymphoblasts are more sensitive to deoxynucleoside toxicity than are B lymphoblasts. These data have led to the use of purine enzyme inhibitors as selective chemotherapeutic drugs in the treatment of T cell malignancies ranging from T cell acute lymphoblastic leukaemia to cutaneous T cell lymphomas. We have compared the toxicities of 2′-deoxyadenosine, 2′-deoxyguanosine, and thymidine for T cell lines derived from patients with T cell acute lymphoblastic leukaemia with those for mature T cell lines derived from patients with cutaneous T cell leukaemia/lymphoma. We have found that both deoxynucleosides are far less toxic to the mature T cell lies than to T lymphoblasts and that the mature cells accumulate much lower amounts of dATP and dGTP when exposed to deoxyadenosine and deoxyguanosine, respectively. Similar studies performed on peripheral blood cells from patients with T cell leukaemias of mature phenotype and on peripheral blood T cells demonstrate similar low amounts of deoxynucleotide accumulation. Measurements of the activities of several purine metabolizing enzymes that participate in deoxynucleoside phosphorylation or degradation do not reveal differences which would explain the toxicity of deoxynucleosides for immature, as compared to mature, T cells. We conclude that deoxynucleoside metabolism in leukaemic T cells varies with their degree of differentiation. These observations may be relevant to the design of chemotherapeutic regimes for T cell malignancies.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72479/1/j.1365-2141.1985.tb04067.x.pd

    Reach-scale bankfull channel types can exist independently of catchment hydrology

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    © 2020 John Wiley &amp; Sons, Ltd. Reach-scale morphological channel classifications are underpinned by the theory that each channel type is related to an assemblage of reach- and catchment-scale hydrologic, topographic, and sediment supply drivers. However, the relative importance of each driver on reach morphology is unclear, as is the possibility that different driver assemblages yield the same reach morphology. Reach-scale classifications have never needed to be predicated on hydrology, yet hydrology controls discharge and thus sediment transport capacity. The scientific question is: do two or more regions with quantifiable differences in hydrologic setting end up with different reach-scale channel types, or do channel types transcend hydrologic setting because hydrologic setting is not a dominant control at the reach scale? This study answered this question by isolating hydrologic metrics as potential dominant controls of channel type. Three steps were applied in a large test basin with diverse hydrologic settings (Sacramento River, California) to: (1) create a reach-scale channel classification based on local site surveys, (2) categorize sites by flood magnitude, dimensionless flood magnitude, and annual hydrologic regime type, and (3) statistically analyze two hydrogeomorphic linkages. Statistical tests assessed the spatial distribution of channel types and the dependence of channel type morphological attributes by hydrologic setting. Results yielded 10 channel types. Nearly all types existed across all hydrologic settings, which is perhaps a surprising development for hydrogeomorphology. Downstream hydraulic geometry relationships were statistically significant. In addition, cobble-dominated uniform streams showed a consistent inverse relationship between slope and dimensionless flood magnitude, an indication of dynamic equilibrium between transport capacity and sediment supply. However, most morphological attributes showed no sorting by hydrologic setting. This study suggests that median hydraulic geometry relations persist across basins and within channel types, but hydrologic influence on geomorphic variability is likely due to local influences rather than catchment-scale drivers. © 2020 John Wiley &amp; Sons, Ltd

    A Database of Wing Diversity in the Hawaiian Drosophila

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    Background. Within genus Drosophila, the endemic Hawaiian species offer some of the most dramatic examples of morphological and behavioral evolution. The advent of the Drosophila grimshawi genome sequence permits genes of interest to be readily cloned from any of the hundreds of species of Hawaiian Drosophila, offering a powerful comparative approach to defining molecular mechanisms of species evolution. A key step in this process is to survey the Hawaiian flies for characters whose variation can be associated with specific candidate genes. The wings provide an attractive target for such studies: Wings are essentially two dimensional, and genes controlling wing shape, vein specification, pigment production, and pigment pattern evolution have all been identified in Drosophila. Methodology/Principal Findings. We present a photographic database of over 180 mounted, adult wings from 73 species of Hawaiian Drosophila. The image collection, available at FlyBase.org, includes 53 of the 112 known species of picture wing\u27\u27 Drosophila, and several species from each of the other major Hawaiian groups, including the modified mouthparts, modified tarsus, antopocerus, and haleakalae (fungus feeder) groups. Direct image comparisons show that major wing shape changes can occur even between closely related species, and that pigment pattern elements can vary independently of each other. Among the 30 species closest to grimshawi, diverse visual effects are achieved by altering a basic pattern of seven wing spots. Finally, we document major pattern variations within species, which appear to result from reduced diffusion of pigment precursors through the wing blade. Conclusions/Significance. The database highlights the striking variation in size, shape, venation, and pigmentation in Hawaiian Drosophila, despite their generally low levels of DNA sequence divergence. In several independent lineages, highly complex patterns are derived from simple ones. These lineages offer a promising model system to study the evolution of complexity

    Outcome measurement in functional neurological disorder: a systematic review and recommendations.

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    OBJECTIVES: We aimed to identify existing outcome measures for functional neurological disorder (FND), to inform the development of recommendations and to guide future research on FND outcomes. METHODS: A systematic review was conducted to identify existing FND-specific outcome measures and the most common measurement domains and measures in previous treatment studies. Searches of Embase, MEDLINE and PsycINFO were conducted between January 1965 and June 2019. The findings were discussed during two international meetings of the FND-Core Outcome Measures group. RESULTS: Five FND-specific measures were identified-three clinician-rated and two patient-rated-but their measurement properties have not been rigorously evaluated. No single measure was identified for use across the range of FND symptoms in adults. Across randomised controlled trials (k=40) and observational treatment studies (k=40), outcome measures most often assessed core FND symptom change. Other domains measured commonly were additional physical and psychological symptoms, life impact (ie, quality of life, disability and general functioning) and health economics/cost-utility (eg, healthcare resource use and quality-adjusted life years). CONCLUSIONS: There are few well-validated FND-specific outcome measures. Thus, at present, we recommend that existing outcome measures, known to be reliable, valid and responsive in FND or closely related populations, are used to capture key outcome domains. Increased consistency in outcome measurement will facilitate comparison of treatment effects across FND symptom types and treatment modalities. Future work needs to more rigorously validate outcome measures used in this population

    Identifying existing Choosing Wisely recommendations of high relevance and importance to hematology

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    Choosing Wisely (CW) is a medical stewardship initiative led by the American Board of Internal Medicine Foundation in collaboration with professional medical societies in the United States. In an effort to learn from and leverage the work of others, the American Society of Hematology CW Task Force developed a method to identify and prioritize CW recommendations from other medical societies of high relevance and importance to patients with blood disorders and their physicians. All 380 CW recommendations were reviewed and assessed for relevance and importance. Relevance was assessed using the MORE TM relevance scale. Importance was assessed with regard to six guiding principles: harm avoidance, evidence, aggregate cost, relevance, frequency and impact. Harm avoidance was considered the most important principle. Ten highly relevant and important recommendations were identified from a variety of professional societies. Recommendations focused on decreasing unnecessary imaging, blood work, treatments and transfusions, as well as on increasing collaboration across disciplines and considering value when recommending treatments. Many CW recommendations have relevance beyond the society of origin. The methods developed by the ASH CW Task Force could be easily adapted by other Societies to identify additional CW recommendations of relevance and importance to their fields. Am. J. Hematol. 91:787–792, 2016. © 2016 Wiley Periodicals, Inc
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