959 resultados para sedentary lifestyles


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Most of the human population in the western world has access to unlimited calories and leads an increasingly sedentary lifestyle. The propensity to undertake voluntary exercise or indulge in spontaneous physical exercise, which might be termed "exercise salience", is drawing increased scientific attention. Despite its genetic aspects, this complex behaviour is clearly modulated by the environment and influenced by physiological states. Inflammation is often overlooked as one of these conditions even though it is known to induce a state of reduced mobility. Chronic subclinical inflammation is associated with the metabolic syndrome; a largely lifestyle-induced disease which can lead to decreased exercise salience. The result is a vicious cycle that increases oxidative stress and reduces metabolic flexibility and perpetuates the disease state. In contrast, hormetic stimuli can induce an anti-inflammatory phenotype, thereby enhancing exercise salience, leading to greater biological fitness and improved functional longevity. One general consequence of hormesis is upregulation of mitochondrial function and resistance to oxidative stress. Examples of hormetic factors include calorie restriction, extreme environmental temperatures, physical activity and polyphenols. The hormetic modulation of inflammation, and thus, exercise salience, may help to explain the highly heterogeneous expression of voluntary exercise behaviour and therefore body composition phenotypes of humans living in similar obesogenic environments.

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The endocannabinoid system (ECS) was only 'discovered' in the 1990s. Since then, many new ligands have been identified, as well as many new intracellular targets--ranging from the PPARs, to mitochondria, to lipid rafts. It was thought that blocking the CB-1 receptor might reverse obesity and the metabolic syndrome. This was based on the idea that the ECS was dysfunctional in these conditions. This has met with limited success. The reason may be that the ECS is a homeostatic system, which integrates energy seeking and storage behaviour with resistance to oxidative stress. It could be viewed as having thrifty actions. Thriftiness is an innate property of life, which is programmed to a set point by both environment and genetics, resulting in an epigenotype perfectly adapted to its environment. This thrifty set point can be modulated by hormetic stimuli, such as exercise, cold and plant micronutrients. We have proposed that the physiological and protective insulin resistance that underlies thriftiness encapsulates something called 'redox thriftiness', whereby insulin resistance is determined by the ability to resist oxidative stress. Modern man has removed most hormetic stimuli and replaced them with a calorific sedentary lifestyle, leading to increased risk of metabolic inflexibility. We suggest that there is a tipping point where lipotoxicity in adipose and hepatic cells induces mild inflammation, which switches thrifty insulin resistance to inflammation-driven insulin resistance. To understand this, we propose that the metabolic syndrome could be seen from the viewpoint of the ECS, the mitochondrion and the FOXO group of transcription factors. FOXO has many thrifty actions, including increasing insulin resistance and appetite, suppressing oxidative stress and shifting the organism towards using fatty acids. In concert with factors such as PGC-1, they also modify mitochondrial function and biogenesis. Hence, the ECS and FOXO may interact at many points; one of which may be via intracellular redox signalling. As cannabinoids have been shown to modulate reactive oxygen species production, it is possible that they can upregulate anti-oxidant defences. This suggests they may have an 'endohormetic' signalling function. The tipping point into the metabolic syndrome may be the result of a chronic lack of hormetic stimuli (in particular, physical activity), and thus, stimulus for PGC-1, with a resultant reduction in mitochondrial function and a reduced lipid capacitance. This, in the context of a positive calorie environment, will result in increased visceral adipose tissue volume, abnormal ectopic fat content and systemic inflammation. This would worsen the inflammatory-driven pathological insulin resistance and inability to deal with lipids. The resultant oxidative stress may therefore drive a compensatory anti-oxidative response epitomised by the ECS and FOXO. Thus, although blocking the ECS (e.g. via rimonabant) may induce temporary weight loss, it may compromise long-term stress resistance. Clues about how to modulate the system more safely are emerging from observations that some polyphenols, such as resveratrol and possibly, some phytocannabinoids, can modulate mitochondrial function and might improve resistance to a modern lifestyle.

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Plant pathology has a long-standing tradition of classifying microbes as pathogens, endophytes or saprophytes. Lifestyles of pathogens are categorized as biotrophic, necrotrophic or hemibiotrophic. Botrytis species are considered by many to be archetypal examples of necrotrophic fungi, with B. cinerea being the most extensively studied species because of its broad host range and economic impact. In this review, we discuss recent work which illustrates that B. cinerea is capable of colonizing plants internally, presumably as an endophyte, without causing any disease or stress symptoms. The extent of the facultative endophytic behaviour of B. cinerea and its relevance in the ecology and disease epidemiology may be vastly underestimated. Moreover, we discuss the recent discovery of a novel Botrytis species, B. deweyae, which normally grows as an endophyte in ornamental daylilies (Hemerocallis), but displays facultative pathogenic behaviour, and is increasingly causing economic damage. We propose that the emergence of endophytes ‘gone rogue’ as novel diseases may be related to increased inbreeding of hybrid lines and reduced genetic diversity. These observations lead us to argue that the sometimes inflexible classification of pathogenic microbes by their lifestyles requires serious reconsideration. There is much more variety to the interactions of Botrytis with its hosts than the eye (or the plant pathologist) can see, and this may be true for other microbes interacting with plants.

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In mammals, the mass-specific rate of biomass production during gestation and lactation, here called maternal productivity, has been shown to vary with body size and lifestyle. Metabolic theory predicts that post-weaning growth of offspring, here termed juvenile productivity, should be higher than maternal productivity, and juveniles of smaller species should be more productive than those of larger species. Furthermore because juveniles generally have similar lifestyles to their mothers, across species juvenile and maternal productivities should be correlated. We evaluated these predictions with data from 270 species of placental mammals in 14 taxonomic/lifestyle groups. All three predictions were supported. Lagomorphs, perissodactyls and artiodactyls were very productive both as juveniles and as mothers as expected from the abundance and reliability of their foods. Primates and bats were unproductive as juveniles and as mothers, as expected as an indirect consequence of their low predation risk and consequent low mortality. Our results point the way to a mechanistic explanation for the suite of correlated life-history traits that has been called the slow–fast continuum.

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Washing machine and dishwasher appliance use accounts for approximately 10% of electricity demand in EU households. The majority of this demand is due to the operation of electric heating elements inside appliances. This paper investigates the potential benefits that can be realised by adding a hot fill connection to washing appliances, with respect to carbon emissions, demand side management and renewable energy integration. Initial laboratory testing of new hot and cold fill appliances has resulted in modifications to optimise hot fill intake, and a novel numerical model presents a method of characterising appliance electricity use in different configurations. In order to validate model findings and test the use of new hot fill appliances in situ, a pilot study has recorded appliances’ resource consumption at one-minute resolution in fourteen households. The addition of hot fill reduced the total dishwasher and washing machine electricity consumption by 38% and 67% respectively. Depending on how hot water is supplied to appliances it is estimated that hot fill use results in an annual household carbon saving of up to 147 kgCO2. Further to direct electricity reduction, hot fill appliances can offer a method of time shifting demand away from peak periods without inconveniencing occupants’ lifestyles.

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Purpose Personalised intervention may have greater potential for reducing the global burden of non-communicable diseases and for promoting better health and wellbeing across the life-span than the conventional “one size fits all” approach. However, the characteristics of individuals interested in personalised nutrition (PN) are unclear. Therefore, the aim of this study was to describe the characteristics of European adults interested in taking part in an internet-based PN study. Methods Individuals from seven European countries (UK, Ireland, Germany, the Netherlands, Spain, Greece and Poland) were invited to participate in the study via the Food4Me website (http://www.food4me.org). Two screening questionnaires were used to collect data on socio-demographic, anthropometric and health characteristics as well as dietary intakes. Results A total of 5662 individuals expressed an interest in the study (mean age 40 ± 12.7; range 15-87 years). Of these 64.6% were female and 96.9% were Caucasian. Overall, 12.9% were smokers and 46.8% reported the presence of a clinically diagnosed disease. Furthermore, 46.9% were overweight or obese and 34.9% were sedentary during leisure time. Assessment of dietary intakes showed that 54.3% of individuals reported consuming at least 5 portions of fruit and vegetables per day, 45.9% consumed more than 3 servings of wholegrains and 37.2% limited their salt intake to less than 5.75g per day. Conclusions Our data indicate that individuals volunteering to participate in an internet-based PN study are broadly representative of the European adult population, most of whom had adequate nutrient intakes but who could benefit from improved dietary choices and greater physical activity. Future use of internet-based PN approaches is thus relevant to a wide target audience.

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The Pre-Pottery Neolithic A (PPNA) period in Southwest Asia is essential for our understanding of the transition to sedentary, agricultural communities. Developments in architecture are key to understanding this transition, but many aspects of PPNA architecture remain elusive, such as construction techniques, the selection of building materials, and the functional use of space. The primary aim of the research described within this contribution was to build a PPNA-like structure in order to answer questions about PPNA architecture in general, while specifically addressing issues raised by the excavation of structures at the site of WF16, Southern Jordan. The second aim was to display a ‘PPNA’ building to visitors in Wadi Faynan to enhance their understanding of the period. The experimental construction based on one of the WF16 structures showed that 1) required materials can be acquired locally; 2) a construction technique using mud layers as described in this paper was likely used; 3) flat, or very slightly dome-shaped, roofs are functional and can also be used as a solid working platform; 4) the WF16 small semi-subterranean buildings appear inappropriate for housing a nuclear family unit.

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Background: The high prevalence of physical inactivity worldwide calls for innovative and more effective ways to promote physical activity (PA). There are limited objective data on the effectiveness of Web-based personalized feedback on increasing PA in adults. Objective: It is hypothesized that providing personalized advice based on PA measured objectively alongside diet, phenotype, or genotype information would lead to larger and more sustained changes in PA, compared with nonpersonalized advice. Methods: A total of 1607 adults in seven European countries were randomized to either a control group (nonpersonalized advice, Level 0, L0) or to one of three personalized groups receiving personalized advice via the Internet based on current PA plus diet (Level 1, L1), PA plus diet and phenotype (Level 2, L2), or PA plus diet, phenotype, and genotype (Level 3, L3). PA was measured for 6 months using triaxial accelerometers, and self-reported using the Baecke questionnaire. Outcomes were objective and self-reported PA after 3 and 6 months. Results: While 1270 participants (85.81% of 1480 actual starters) completed the 6-month trial, 1233 (83.31%) self-reported PA at both baseline and month 6, but only 730 (49.32%) had sufficient objective PA data at both time points. For the total cohort after 6 months, a greater improvement in self-reported total PA (P=.02) and PA during leisure (nonsport) (P=.03) was observed in personalized groups compared with the control group. For individuals advised to increase PA, we also observed greater improvements in those two self-reported indices (P=.006 and P=.008, respectively) with increased personalization of the advice (L2 and L3 vs L1). However, there were no significant differences in accelerometer results between personalized and control groups, and no significant effect of adding phenotypic or genotypic information to the tailored feedback at month 3 or 6. After 6 months, there were small but significant improvements in the objectively measured physical activity level (P<.05), moderate PA (P<.01), and sedentary time (P<.001) for individuals advised to increase PA, but these changes were similar across all groups. Conclusions: Different levels of personalization produced similar small changes in objective PA. We found no evidence that personalized advice is more effective than conventional “one size fits all” guidelines to promote changes in PA in our Web-based intervention when PA was measured objectively. Based on self-reports, PA increased to a greater extent with more personalized advice. Thus, it is crucial to measure PA objectively in any PA intervention study.

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Background: Daily consumption of Concord grape juice (CGJ) over three to four months has been shown to improve memory function in adults with mild cognitive impairment, and reduce blood pressure in hypertensive adults. These benefits are likely due to the high concentration of polyphenols in CGJ. Increased stress can impair cognitive function and elevate blood pressure. Thus we examined the potential beneficial effect of CGJ in individuals experiencing somewhat stressful demanding lifestyles. Objective: To examine the effects of twelve weeks’ daily consumption of CGJ on cognitive function, driving performance, and blood pressure in healthy, middle-aged working mothers. Design: Twenty five healthy mothers of pre-teen children, aged 40-50 years, who were employed for > 30 hours/week consumed 12oz (355ml) CGJ (containing 777mg total polyphenols) or an energy, taste and appearance matched placebo daily for twelve weeks according to a randomised, crossover design with a four week washout. Verbal and spatial memory, executive function, attention, blood pressure and mood were assessed at baseline, six weeks and twelve weeks. Immediately following the cognitive battery, a subsample of seventeen females completed a driving performance assessment in the University of Leeds Driving Simulator. The twenty five minute driving task required participants to match the speed and direction of a lead vehicle. Results: Significant improvements in immediate spatial memory and driving performance were observed following CGJ relative to placebo. There was evidence of an enduring effect of CGJ such that participants who received CGJ in arm 1 maintained better performance in the placebo arm. Conclusions: Cognitive benefits associated with chronic consumption of flavonoid-rich grape juice are not exclusive to adults with mild cognitive impairment. Moreover, these cognitive benefits are apparent in complex everyday tasks such as driving. Effects may persist beyond cessation of flavonoid consumption and future studies should carefully consider the length of washout within crossover designs.

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Children represent the most vulnerable members of society, and as such provide valuable insight into past lifeways. Adverse environmental conditions translate more readily into the osteological record of children, making them primary evidence for the investigation of ill-health in the past. To date, most information on growing up in Roman Britain has been based on the Classical literature, or discussed in palaeopathological studies with a regional focus, e.g. Dorset or Durnovaria. Thus, the lifestyles and everyday realities of children throughout Britannia remained largely unknown. This study sets out to fill this gap by providing the first large scale analysis of Romano-British children from town and country. The palaeopathological analysis of 1643 non-adult (0-17 years) skeletons, compiled from the literature (N=690) and primary osteological analysis (N=953), from 27 urban and rural settlements has highlighted diverse patterns in non-adult mortality and morbidity. The distribution of ages-at-death suggest that older children and adolescents migrated from country to town, possibly for commencing their working lives. True prevalence rates suggest that caries (1.8%) and enamel hypoplasia (11.4%) were more common in children from major urban towns, whereas children in the countryside displayed higher frequencies of scurvy (6.9%), cribra orbitalia (27.7%), porotic hyperostosis (6.2%) and endocranial lesions (10.9%). Social inequality in late Roman Britain may have been the driving force behind these urban-rural dichotomies. The results may point to exploitation of the peasantry on the one hand, and higher status of the urban population as a more ‘Romanised’ group on the other. Comparison with Iron Age and post-medieval non-adults also demonstrated a decline in health in the Roman period, with some levels of ill-health, particularly in the rural children, similar to those from post-medieval London. This research provides the most comprehensive study of non-adult morbidity and mortality in Roman Britain to date. It has provided new insights into Romano-British lifeways and presents suggestions for further work.

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Fire-centred studies have recently been highlighted as powerful avenues for investigation of energy flows and relations between humans, materials, environments and other species. The aim in this paper is to evaluate this potential first by reviewing the diverse theories and methods that can be applied to investigate the ecological and social significance of anthropogenic fire, and second by applying these to new and existing data sets in archaeology. This paper examines how fire-centred approaches can inform on one of the most significant step-changes in human lifeways and inter-relations with environment and other species – the transition from mobile hunting-gathering to more sedentary agriculture in a key heartland of change, the Zagros region of Iraq and Iran, c. 12,000–8,000 BP. In the review and case studies multiple links are investigated between human fire use and environment, ecology, energy use, technology, the built environment, health, social roles and relations, cultural practices and catastrophic events

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Self-report underpins our understanding of falls among people with Parkinson’s (PwP) as they largely happen unwitnessed at home. In this qualitative study, we used an ethnographic approach to investigate which in-home sensors, in which locations, could gather useful data about fall risk. Over six weeks, we observed five independently mobile PwP at high risk of falling, at home. We made field notes about falls (prior events and concerns) and recorded movement with video, Kinect, and wearable sensors. The three women and two men (aged 71 to 79 years) having moderate or severe Parkinson’s were dependent on others and highly sedentary. We most commonly noted balance protection, loss, and restoration during chair transfers, walks across open spaces and through gaps, turns, steps up and down, and tasks in standing (all evident walking between chair and stairs, e.g.). Our unobtrusive sensors were acceptable to participants: they could detect instability during everyday activity at home and potentially guide intervention. Monitoring the route between chair and stairs is likely to give information without invading the privacy of people at high risk of falling, with very limited mobility, who spend most of the day in their sitting rooms.

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Mobility is a fundamental facet of being human and should be central to archaeology. Yet mobility itself and the role it plays in the production of social life, is rarely considered as a subject in its own right. This is particularly so with discussions of the Neolithic people where mobility is often framed as being somewhere between a sedentary existence and nomadic movements. This volume examines the importance and complexities of movement and mobility, whether on land or water, in the Neolithic period. It uses movement in its widest sense, ranging from everyday mobilities – the routines and rhythms of daily life – to proscribed mobility, such as movement in and around monuments, and occasional and large-scale movements and migrations around the continent and across seas. Papers are roughly grouped and focus on ‘mobility and the landscape’, ‘monuments and mobility’, ‘travelling by water’, and ‘materials and mobility’. Through these themes the volume considers the movement of people, ideas, animals, objects, and information, and uses a wide range of archaeological evidence from isotope analysis; artefact studies; lithic scatters and assemblage diversity.

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The objective of this paper was to assess sex and socioeconomic inequalities in lung cancer mortality in two major cities of Europe and South America. Official information on mortality and population allowed the estimation of sex- and age-specific death rates for Barcelona, Spain and Sao Paulo, Brazil (1995-2003). Mortality trends and levels were independently assessed for each city and subsequently compared. Rate ratios assessed by Poisson regression analysis addressed hypotheses of association between the outcome and socioeconomic covariates (human development index, unemployment and schooling) at the inner-city area level. Barcelona had a higher mortality in men (76.9/100000 inhabitants) than Sao Paulo (38.2/100 000 inhabitants); although rates were decreasing for the former (-2%/year) and levelled-off for the [after. Mortality in women ranked similarly (9.1 for Barcelona, 11.5 for Sao Paulo); with an increasing trend for women aged 35-64 years (+ 7.7%/year in Barcelona and + 2.4%/year in Sao Paulo). The socioeconomic gradient of mortality in men was negative for Barcelona and positive for Sao Paulo; for women, the socioeconomic gradient was positive in both cities. Negative gradients indicate that deprived areas suffer a higher burden of disease; positive gradients suggest that prosmoking lifestyles may have been more prevalent in more affluent areas during the last decades. Sex and socioeconomic inequalities of lung cancer mortality reinforce the hypothesis that the epidemiologic profile of cancer can be improved by an expanded access to existing technology of healthcare and prevention. The continuous monitoring of inequalities in health may contribute to the concurrent promotion of well-being and social justice.

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Obesity is an increasingly serious public health problem on a global level. Morbid obesity, defined as a body mass index greater than 40 kg/m(2), is associated with increased mortality and a high burden of obesity-related morbidities. To study the prevalence of morbid obesity in Brazil, three national anthropometric surveys were reanalyzed. Data about bariatric surgeries were obtained from the Ministry of Health Hospital Information System, which is available online. A 255% rise in the prevalence of morbid obesity was observed, starting at 0.18% in 1975-1976 and growing to 0.33% in 1989 and 0.64% in 2002-2003. There was a higher rate in the South in the first two surveys, but the prevalence in the Southeast rose steadily, reaching 0.77% in 2002-2003 and overtaking the South. Since 1999, the Brazilian Unified Health System has covered surgical treatment for morbid obesity. From 2000 to 2006, there was a sixfold increase in the number of surgeries, which topped the 2,500 mark in 2006. The geographic distribution of these surgeries is heavily concentrated in the Southeast, the most developed region of Brazil, where there is also the highest prevalence of morbid obesity. This was followed by the Southern region. The figures for the rise in morbid obesity in Brazil are startling, especially the increase among men. This is a situation that calls for further study, alongside measures to encourage the adoption of healthy lifestyles. Preventive measures aimed at slowing down or reversing the obesity epidemic are urgently required.