66 research outputs found
Supporting active ageing before retirement : a systematic review and meta-analysis of workplace physical activity interventions targeting older employees
Objective: With the growing representation of older adults in the workforce, the health and fitness of older employees are critical to support active ageing policies. This systematic review aimed to characterise and evaluate the effects on physical activity (PA) and fitness outcomes of workplace PA interventions targeting older employees. Design: We searched Medline, PreMedline, PsycInfo, CINAHL and the Cochrane Controlled Register of Trials (CENTRAL) for articles published from inception to 17 February 2020. Eligible studies were of any experimental design, included employees aged ≥50 years, had PA as an intervention component and reported PA-related outcomes. Results: Titles and abstracts of 8168 records were screened, and 18 unique interventions were included (3309 participants). Twelve studies were randomised controlled trials (RCTs). Seven interventions targeted multiple risk factors (n=1640), involving screening for cardiovascular disease risk factors, but had a non-specific description of the PA intervention. Four interventions targeted nutrition and PA (n=1127), and seven (n=235) focused only on PA. Interventions overwhelmingly targeted aerobic PA, compared with only four interventions targeting strength and/or balance (n=106). No studies involved screening for falls/injury risk, and only two interventions targeted employees of low socioeconomic status. Computation of effect sizes (ESs) was only possible in a maximum of three RCTs per outcome. ESs were medium for PA behaviour (ES=0.25 95% CI −0.07 to 0.56), muscle strength (ES=0.27, 95% CI −0.26 to 0.80), cardiorespiratory fitness (ES=0.28, 95% CI −22 to 0.78), flexibility (ES=0.50, 95% CI −0.04 to 1.05) and balance (ES=0.74, 95% CI −0.21 to 1.69). Grading of Recommendations Assessment, Development and Evaluation criteria-rated quality of evidence was ‘low’ due to high risk of bias, imprecision and inconsistency. Conclusions: The lack of high-quality effective workplace PA interventions contrasts the importance and urgency to improve the health and fitness in this population. Future interventions should incorporate strength and balance training and screening of falls/injury risk in multi risk factors approaches
Occurrence of Clavibacter michiganensis subsp. michiganensis, the causal agent of bacterial canker of tomato, in Syria
Several surveys were carried out to evaluate the occurrence of bacterial canker of tomato caused by Clavibacter michiganensis subsp. michiganensis (Cmm) in Syria, especially in the North-West provinces Latakiaand Tartous. The surveys revealed typical disease symptoms in greenhouses where the tomato cvs. Dima, Huda and Astona were grown, such as dark brown to black lesions on the leaf margins, wilting of whole plants, stunting, and vascular discoloration. The disease incidence in such greenhouses was 15% in the spring of 2007, and up to 70% by the end of July. Ten isolates obtained from diseased plants at different locations in these two provinces were identified as Clavibacter michiganensis subsp. michiganensis using classical microbiological tests as well as PCR. This is the first detailed proof of the occurrence of bacterial canker of tomato in Syria
Gene and genon concept: coding versus regulation: A conceptual and information-theoretic analysis of genetic storage and expression in the light of modern molecular biology
We analyse here the definition of the gene in order to distinguish, on the basis of modern insight in molecular biology, what the gene is coding for, namely a specific polypeptide, and how its expression is realized and controlled. Before the coding role of the DNA was discovered, a gene was identified with a specific phenotypic trait, from Mendel through Morgan up to Benzer. Subsequently, however, molecular biologists ventured to define a gene at the level of the DNA sequence in terms of coding. As is becoming ever more evident, the relations between information stored at DNA level and functional products are very intricate, and the regulatory aspects are as important and essential as the information coding for products. This approach led, thus, to a conceptual hybrid that confused coding, regulation and functional aspects. In this essay, we develop a definition of the gene that once again starts from the functional aspect. A cellular function can be represented by a polypeptide or an RNA. In the case of the polypeptide, its biochemical identity is determined by the mRNA prior to translation, and that is where we locate the gene. The steps from specific, but possibly separated sequence fragments at DNA level to that final mRNA then can be analysed in terms of regulation. For that purpose, we coin the new term “genon”. In that manner, we can clearly separate product and regulative information while keeping the fundamental relation between coding and function without the need to introduce a conceptual hybrid. In mRNA, the program regulating the expression of a gene is superimposed onto and added to the coding sequence in cis - we call it the genon. The complementary external control of a given mRNA by trans-acting factors is incorporated in its transgenon. A consequence of this definition is that, in eukaryotes, the gene is, in most cases, not yet present at DNA level. Rather, it is assembled by RNA processing, including differential splicing, from various pieces, as steered by the genon. It emerges finally as an uninterrupted nucleic acid sequence at mRNA level just prior to translation, in faithful correspondence with the amino acid sequence to be produced as a polypeptide. After translation, the genon has fulfilled its role and expires. The distinction between the protein coding information as materialised in the final polypeptide and the processing information represented by the genon allows us to set up a new information theoretic scheme. The standard sequence information determined by the genetic code expresses the relation between coding sequence and product. Backward analysis asks from which coding region in the DNA a given polypeptide originates. The (more interesting) forward analysis asks in how many polypeptides of how many different types a given DNA segment is expressed. This concerns the control of the expression process for which we have introduced the genon concept. Thus, the information theoretic analysis can capture the complementary aspects of coding and regulation, of gene and genon
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