The International Physical Activity Questionnaire-Short Form (IPAQ-SF) has been recommended as a cost-effective method to assess physical activity. Several studies validating the IPAQ-SF have been ...conducted with differing results, but no systematic review of these studies has been reported.
The keywords "IPAQ", "validation", and "validity" were searched in PubMed and Scopus. Studies published in English that validated the IPAQ-SF against an objective physical activity measuring device, doubly labeled water, or an objective fitness measure were included.
Twenty-three validation studies were included in this review. There was a great deal of variability in the methods used across studies, but the results were largely similar. Correlations between the total physical activity level measured by the IPAQ-SF and objective standards ranged from 0.09 to 0.39; none reached the minimal acceptable standard in the literature (0.50 for objective activity measuring devices, 0.40 for fitness measures). Correlations between sections of the IPAQ-SF for vigorous activity or moderate activity level/walking and an objective standard showed even greater variability (-0.18 to 0.76), yet several reached the minimal acceptable standard. Only six studies provided comparisons between physical activity levels derived from the IPAQ-SF and those obtained from objective criterion. In most studies the IPAQ-SF overestimated physical activity level by 36 to 173 percent; one study underestimated by 28 percent.
The correlation between the IPAQ-SF and objective measures of activity or fitness in the large majority of studies was lower than the acceptable standard. Furthermore, the IPAQ-SF typically overestimated physical activity as measured by objective criterion by an average of 84 percent. Hence, the evidence to support the use of the IPAQ-SF as an indicator of relative or absolute physical activity is weak.
Although microalgae are a promising biobased feedstock, industrial scale production is still far off. To enhance the economic viability of large-scale microalgae processes, all biomass components ...need to be valorized, requiring a multi-product biorefinery. However, this concept is still too expensive. Typically, downstream processing of industrial biotechnological bulk products accounts for 20–40% of the total production costs, while for a microalgae multi-product biorefinery the costs are substantially higher (50–60%). These costs are high due to the lack of appropriate and mild technologies to access the different product fractions such as proteins, carbohydrates, and lipids. To reduce the costs, simplified processes need to be developed for the main unit operations including harvesting, cell disruption, extraction, and possibly fractionation.
A multi-product biorefinery is essential to make microalgal production of bulk commodities economically feasible.
Large-scale cultivation using closed photobioreactors makes microalgal harvesting a smaller economic hurdle in a multi-product biorefinery.
Techno-economic scenario studies show that a current multi-product biorefinery requiring multiple unit operations is complex and therefore too expensive.
Process simplification can be accomplished by reducing the number of unit operations (e.g., by integrating unit operations or by avoiding auxiliaries in the process chain), making a multi-product biorefinery economically feasible.
The effect of problematic use of the Internet on mental health, particularly depression among young people, has been established but without a probable model for the underlying mechanism. In this ...study, a model is presented to describe possible pathways for the linkage between Internet gaming addiction and depression possibly mediated by sleep problems. A systematic review was conducted to gather epidemiological evidence to support or refute the link between addictive Internet gaming, problematic Internet use, and sleep problems including insomnia and poor sleep quality. Seven studies were identified through a systematic literature search, of these three related to addictive Internet gaming and four on problematic Internet uses and sleep problems. Information was extracted and analysed systematically from each of the studies and tabulated as a summary. Results of the review suggest that additive gaming, particularly massively multiplayer online role-playing games MMORPG, might be associated with poorer quality of sleep. Results further indicated that problematic Internet use was associated with sleep problems including subjective insomnia and poor sleep quality.
The dairy industry in the developed world has undergone profound changes over recent decades. In this paper, we present an overview of some of the most important recent changes in the dairy industry ...that affect health and welfare of dairy cows, as well as the science associated with these changes. Additionally, knowledge gaps are identified where research is needed to guide the dairy industry through changes that are occurring now or that we expect will occur in the future. The number of farms has decreased considerably, whereas herd size has increased. As a result, an increasing number of dairy farms depend on hired (nonfamily) labor. Regular professional communication and establishment of farm-specific protocols are essential to minimize human errors and ensure consistency of practices. Average milk production per cow has increased, partly because of improvements in nutrition and management but also because of genetic selection for milk production. Adoption of new technologies (e.g., automated calf feeders, cow activity monitors, and automated milking systems) is accelerating. However, utilization of the data and action lists that these systems generate for health and welfare of livestock is still largely unrealized, and more training of dairy farmers, their employees, and their advisors is necessary. Concurrently, to remain competitive and to preserve their social license to operate, farmers are increasingly required to adopt increased standards for food safety and biosecurity, become less reliant on the use of antimicrobials and hormones, and provide assurances regarding animal welfare. Partly because of increasing herd size but also in response to animal welfare regulations in some countries, the proportion of dairy herds housed in tiestalls has decreased considerably. Although in some countries access to pasture is regulated, in countries that traditionally practiced seasonal grazing, fewer farmers let their dairy cows graze in the summer. The proportion of organic dairy farms has increased globally and, given the pressure to decrease the use of antimicrobials and hormones, conventional farms may be able to learn from well-managed organic farms. The possibilities of using milk for disease diagnostics and monitoring are considerable, and dairy herd improvement associations will continue to expand the number of tests offered to diagnose diseases and pregnancy. Genetic and genomic selection for increased resistance to disease offers substantial potential but requires collection of additional phenotypic data. There is every expectation that changes in the dairy industry will be further accentuated and additional novel technologies and different management practices will be adopted in the future.
Good udder health is not only important for the dairy farmer but, because of increasing interest of consumers in the way dairy products are produced, also for the dairy production chain as a whole. ...An important role of veterinarians is in advising on production diseases such as mastitis. A large part of this advice is given around the planning of management to maintain or improve the udder health status of a farm.
Mastitis is a costly disease, due to losses (a reduction of output due to mastitis) and expenditure (additional inputs to reduce the level of mastitis). Worldwide, published estimates of the economic losses of clinical mastitis range from €61 to €97 per cow on a farm, with large differences between farms, e.g. in The Netherlands, losses due to clinical and subclinical mastitis varied between €17 and €198 per cow per year. Moreover, farmers tended to underestimate these costs. This indicates that for a large proportion of farms there are many avoidable losses. In order to provide good support to farmers' decision-making, it is important to describe the mastitis setting not only in terms of disease, e.g. incidence of clinical mastitis, but also in monetary terms; and to make good decisions, it is necessary to provide the dairy farmer with information on the additional expenditure and reduced losses associated with alternative decisions. Six out of 18 preventive measures were shown to have a positive nett benefit, viz blanket use of dry-cow therapy, keeping cows standing after milking, back-flushing of the milk cluster after milking a cow with clinical mastitis, application of a treatment protocol, washing dirty udders, and the use of milkers' gloves. For those measures that included a large amount of routine labour or investment, the reduced losses did not outweigh the additional expenditure.
The advisor cannot expect that measures that are cost-effective are always implemented. Reasons for this are the objectives of the dairy farmer can be other than maximisation of profit, resources to improve the mastitis situation compete with other fields of management, risk involved with the decision, economic behaviour of the dairy farmer, and valuation of the cost factors by the dairy farmer. For all decision-makers this means that, although financial incentives do have an effect on the management of mastitis, it is not always sufficient to show the economic benefits of improved management to induce an improvement of management of mastitis.
Enhancer RNAs and regulated transcriptional programs Lam, Michael T.Y.; Li, Wenbo; Rosenfeld, Michael G. ...
Trends in biochemical sciences (Amsterdam. Regular ed.),
04/2014, Volume:
39, Issue:
4
Journal Article
Peer reviewed
Open access
•Active enhancers generate enhancer-derived RNAs (eRNAs).•At least some eRNAs contribute to enhancer function.•eRNAs may play roles in enhancer–promoter interactions.
A large portion of the human ...genome is transcribed into RNAs without known protein-coding functions, far outnumbering coding transcription units. Extensive studies of long noncoding RNAs (lncRNAs) have clearly demonstrated that they can play critical roles in regulating gene expression, development, and diseases, acting both as transcriptional activators and repressors. More recently, enhancers have been found to be broadly transcribed, resulting in the production of enhancer-derived RNAs, or eRNAs. Here, we review emerging evidence suggesting that at least some eRNAs contribute to enhancer function. We discuss these findings with respect to potential mechanisms of action of eRNAs and other ncRNAs in regulated gene expression.
Internet gaming addiction was included in the latest version of the DSM-V as a possible disorder recently, while debate is still on-going as to whether the condition called “Internet Addiction” (IA) ...could be fully recognised as an established disorder. The major contention is how well IA could fulfil the validation criteria as a psychiatric disorder as in other well-established behavioural addictions. In addition to various proposed validation criteria, evidence of risk and protective factors as well as development of outcomes from longitudinal and prospective studies are suggested as important. A systematic review of available longitudinal and prospective studies was conducted to gather epidemiological evidence on risk and protective factors of IA and the health effect of IA on adolescents. Nine articles were identified after an extensive search of the literature in accordance to the PRISMA guidelines. Of these, eight provided data on risk or protective factors of IA and one focused solely on the effects of IA on mental health. Information was extracted and analysed systematically from each study and tabulated. Many exposure variables were studied and could be broadly classified into three main categories: psychopathologies of the participants, family and parenting factors, and others such as Internet usage, motivation, and academic performance. Some were found to be potential risk or protective factors of IA. It was also found that exposure to IA had a detrimental effect on the mental health of young people. These results were discussed in light of their implications to the fulfilment of the validation criteria.
The gastrointestinal (GI) tract is a highly specialized sensory organ that provides crucial negative feedback during a meal, partly via a gut–brain axis. More specifically, enteroendocrine cells ...located throughout the GI tract are able to sense and respond to specific nutrients, releasing gut peptides that act in a paracrine, autocrine or endocrine fashion to regulate energy balance, thus controlling both food intake and possibly energy expenditure. Furthermore, the gut microbiota has been shown to provide a substantial metabolic and physiological contribution to the host, and metabolic disease such as obesity has been associated with aberrant gut microbiota and microbiome. Interestingly, recent evidence suggests that the gut microbiota can impact the gut–brain axis controlling energy balance, at both the level of intestinal nutrient‐sensing mechanisms, as well as potentially at the sites of integration in the central nervous system. A better understanding of the intricate relationship between the gut microbiota and host energy‐regulating pathways is crucial for uncovering the mechanisms responsible for the development of metabolic diseases and for possible therapeutic strategies.
The gastrointestinal tract maintains energy and glucose homeostasis, in part through nutrient-sensing and subsequent signaling to the brain and other tissues. In this review, we highlight the role of ...small intestinal nutrient-sensing in metabolic homeostasis, and link high-fat feeding, obesity, and diabetes with perturbations in these gut-brain signaling pathways. We identify how lipids, carbohydrates, and proteins, initiate gut peptide release from the enteroendocrine cells through small intestinal sensing pathways, and how these peptides regulate food intake, glucose tolerance, and hepatic glucose production. Lastly, we highlight how the gut microbiota impact small intestinal nutrient-sensing in normal physiology, and in disease, pharmacological and surgical settings. Emerging evidence indicates that the molecular mechanisms of small intestinal nutrient sensing in metabolic homeostasis have physiological and pathological impact as well as therapeutic potential in obesity and diabetes.
A ring idempotent
is said to be quarter-central (or q-central for short) if
. If all idempotents in a ring
are q-central,
is said to be a quarter-abelian ring (or more simply, a q-abelian ring). In ...this paper, we show that such a ring
is characterized by the property that
for all idempotents
, where
denotes the additive commutator
. For any nonzero ring
and any integer
, we show that the ring
of
upper triangular matrices over
is not q-abelian. On the other hand,
is q-abelian iff
is abelian (in the classical sense that all idempotents are central in
). A final section of this paper relates q-central idempotents to the notion of exchange rings and the study of regular, unit-regular, and strongly regular elements in arbitrary rings. From the viewpoint of currently prevailing generalizations of abelian rings in the literature, q-abelian rings are situated between the class of semiabelian rings and the class of strongly IC rings.
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