1,733 research outputs found
Tropical forager gastrophagy and its implications for extinct hominin diets
Reconstruction of extinct hominin diets is currently a topic of much interest and debate, facilitated by new methods such as the analysis of dental calculus. It has been proposed, based on chemical analyses of calculus, that Neanderthals self-medicated, yet this conclusion has been questioned. Gastrophagy has been suggested as an alternative explanation for the Neanderthal data, based on ethnographic analogies, which show this practice to have been widespread in traditional extant Homo sapiens diets, and nutritional evidence for its benefits at high latitudes. Here we expand the discussion of the potential importance of gastrophagy in human evolution by considering its role for an extant group of tropical foragers, the Hadza of Tanzania, and questioning its role in the diets of extinct tropical hominin species. Gastrophagy is frequently practiced among the Hadza and adult men in particular consume substantial, seasonally variable, amounts of prey guts. In addition to the important fact that gastrophagy is not a rare event, this demographic information may be useful in interpreting evidence from archaeological samples. The consumption of semi-digested chyme would have allowed extinct hominins to gain calories from plant sources without the cost of digesting them, possibly contributing to the encephalisation and shrinking of the gut in genus Homo. As an easy to process food-source, chyme could have likewise been an important food source for the old and the young, potentially playing a part in reducing inter-birth intervals and increasing reproductive success in our lineage. Thus gastrophagy may have played a key part in human evolution and its potentially confounding signal should be considered in future dietary reconstructions.We would like to thank The Calleva Foundation (LTB & CBS), The Human Origins Research Fund, NHM (LTB & CBS), The Leakey Foundation (JCB & BMW), Wenner-Gren Foundation (BMW), & the National Science Foundation (BMW) for funding.This is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/j.jasrep.2015.09.02
Tropical forager gastrophagy and its implications for extinct hominin diets
Reconstruction of extinct hominin diets is currently a topic of much interest and debate, facilitated by new methods such as the analysis of dental calculus. It has been proposed, based on chemical analyses of calculus, that Neanderthals self-medicated, yet this conclusion has been questioned. Gastrophagy has been suggested as an alternative explanation for the Neanderthal data, based on ethnographic analogies, which show this practice to have been widespread in traditional extant Homo sapiens diets, and nutritional evidence for its benefits at high latitudes. Here we expand the discussion of the potential importance of gastrophagy in human evolution by considering its role for an extant group of tropical foragers, the Hadza of Tanzania, and questioning its role in the diets of extinct tropical hominin species. Gastrophagy is frequently practiced among the Hadza and adult men in particular consume substantial
Accreting Millisecond X-Ray Pulsars
Accreting Millisecond X-Ray Pulsars (AMXPs) are astrophysical laboratories
without parallel in the study of extreme physics. In this chapter we review the
past fifteen years of discoveries in the field. We summarize the observations
of the fifteen known AMXPs, with a particular emphasis on the multi-wavelength
observations that have been carried out since the discovery of the first AMXP
in 1998. We review accretion torque theory, the pulse formation process, and
how AMXP observations have changed our view on the interaction of plasma and
magnetic fields in strong gravity. We also explain how the AMXPs have deepened
our understanding of the thermonuclear burst process, in particular the
phenomenon of burst oscillations. We conclude with a discussion of the open
problems that remain to be addressed in the future.Comment: Review to appear in "Timing neutron stars: pulsations, oscillations
and explosions", T. Belloni, M. Mendez, C.M. Zhang Eds., ASSL, Springer;
[revision with literature updated, several typos removed, 1 new AMXP added
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Arthroscopic hip surgery compared with physiotherapy and activity modification for the treatment of symptomatic femoroacetabular impingement: multicentre randomised controlled trial.
OBJECTIVE: To compare arthroscopic hip surgery with physiotherapy and activity modification for improving patient reported outcome measures in patients with symptomatic femoroacetabular impingement (FAI). DESIGN: Two group parallel, assessor blinded, pragmatic randomised controlled trial. SETTING: Secondary and tertiary care centres across seven NHS England sites. PARTICIPANTS: 222 participants aged 18 to 60 years with symptomatic FAI confirmed clinically and with imaging (radiography or magnetic resonance imaging) were randomised (1:1) to receive arthroscopic hip surgery (n=112) or a programme of physiotherapy and activity modification (n=110). Exclusion criteria included previous surgery, completion of a physiotherapy programme targeting FAI within the preceding 12 months, established osteoarthritis (Kellgren-Lawrence grade ≥2), and hip dysplasia (centre-edge angle <20 degrees). INTERVENTIONS: Participants in the physiotherapy group received a goal based programme tailored to individual patient needs, with emphasis on improving core stability and movement control. A maximum of eight physiotherapy sessions were delivered over five months. Participants in the arthroscopic surgery group received surgery to excise the bone that impinged during hip movements, followed by routine postoperative care. MAIN OUTCOME MEASURES: The primary outcome measure was the hip outcome score activities of daily living subscale (HOS ADL) at eight months post-randomisation, with a minimum clinically important difference between groups of 9 points. Secondary outcome measures included additional patient reported outcome measures and clinical assessment. RESULTS: At eight months post-randomisation, data were available for 100 patients in the arthroscopic hip surgery group (89%) and 88 patients in the physiotherapy programme group (80%). Mean HOS ADL was 78.4 (95% confidence interval 74.4 to 82.3) for patients randomised to arthroscopic hip surgery and 69.2 (65.2 to 73.3) for patients randomised to the physiotherapy programme. After adjusting for baseline HOS ADL, age, sex, and study site, the mean HOS ADL was 10.0 points higher (6.4 to 13.6) in the arthroscopic hip surgery group compared with the physiotherapy programme group (P<0.001)). No serious adverse events were reported in either group. CONCLUSIONS: Patients with symptomatic FAI referred to secondary or tertiary care achieve superior outcomes with arthroscopic hip surgery than with physiotherapy and activity modification. TRIAL REGISTRATION: ClinicalTrials.gov NCT01893034.NIHR BRC oxfor
Using historical documentary methods to explore the history of occupational therapy
peer-reviewed.Introduction: Historical research can benefit health professions by providing a basis for understanding how current beliefs and practices developed over time. From an occupational therapy perspective, a need for deeper critical understandings of the profession has been identified; historical research can facilitate this process. Documentary research is a significant methodology in historical inquiry, but there is a dearth of guidance for occupational therapists wishing to employ this method. Method: A conceptual literature review was conducted to describe how to use documentary sources to understand the development of the profession, drawing on literature from the disciplines of history and occupational therapy. Results: The stages of historical documentary research are described: choosing a topic, sourcing and selecting evidence, and managing sources. How to consider the authenticity, credibility and representativeness of historical material is discussed. Various means to determine the meaning of historical evidence are considered, with chronological, thematic and theoretical approaches proposed. Conclusion: Methodological transparency is central to the process of historical documentary research. To enhance understanding of the quality of historical source material, adoption of the guidelines outlined is recommended. Adopting a clearly defined questioning perspective promotes more substantial conclusions and professional understandingspeer-reviewe
Rare variants analysis of cutaneous malignant melanoma genes in Parkinson's disease
A shared genetic susceptibility between cutaneous malignant melanoma (CMM) and Parkinson's disease (PD) has been suggested. We investigated this by assessing the contribution of rare variants in genes involved in CMM to PD risk. We studied rare variation across 29 CMM risk genes using high-quality genotype data in 6875 PD cases and 6065 controls and sought to replicate findings using whole-exome sequencing data from a second independent cohort totaling 1255 PD cases and 473 controls. No statistically significant enrichment of rare variants across all genes, per gene, or for any individual variant was detected in either cohort. There were nonsignificant trends toward different carrier frequencies between PD cases and controls, under different inheritance models, in the following CMM risk genes: BAP1, DCC, ERBB4, KIT, MAPK2, MITF, PTEN, and TP53. The very rare TYR p.V275F variant, which is a pathogenic allele for recessive albinism, was more common in PD cases than controls in 3 independent cohorts. Tyrosinase, encoded by TYR, is the rate-limiting enzyme for the production of neuromelanin, and has a role in the production of dopamine. These results suggest a possible role for another gene in the dopamine-biosynthetic pathway in susceptibility to neurodegenerative Parkinsonism, but further studies in larger PD cohorts are needed to accurately determine the role of these genes/variants in disease pathogenesis
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