Decline in Telomere Length by Age and Effect Modification by Gender, Allostatic Load and Comorbidities in National Health and Nutrition Examination Survey (1999-2002)

Background: This study aims to assess the decline in telomere length (TL) with age and evaluate effect modification by gender, chronic stress, and comorbidity in a representative sample of the US population. Methods: Cross-sectional data on 7826 adults with a TL measurement, were included from the National Health and Nutrition Examination Survey, years 1999–2002. The population rate of decline in TL across 10-year age categories was estimated using crude and adjusted regression. Results: In an adjusted model, the population rate of decline in TL with age was consistent and linear for only three age categories: 20–29 (β = -0.0172, 95% CI: -0.0342, -0.0002), 50–59 (β = -0.0182, 95% CI: -0.0311, -0.0054) and 70–79 (β = -0.0170, 95% CI: -0.0329, -0.0011) years. The population rate of decline in TL with age was significantly greater for males and those with high allostatic load and a history of comorbidities. When the population rate of decline in TL was analyzed by gender in 10-year age bins, a fairly consistent yet statistically non-significant decline for males was observed; however, a trough in the rate was observed for females in the age categories 20–29 years (β = -0.0284, 95% CI: -0.0464, -0.0103) and 50–59 years (β = -0.0211, 95% CI: -0.0391, -0.0032). To further elucidate the gender difference observed in the primary analyses, secondary analyses were conducted with reproductive and hormonal status; a significant inverse association was found between TL and parity, menopause, and age at menopause. Conclusions: TL was shorter with increasing age and this decline was modified by gender, chronic stress and comorbidities; individuals with chronic morbidity and/or chronic stress and females in their twenties and fifties experienced greater decline. Female reproductive factors, i.e., parity and menopause, were associated with TL

Optimised insert design for improved single-molecule imaging and quantification through CRISPR-Cas9 mediated knock-in

© 2019, The Author(s). The use of CRISPR-Cas9 genome editing to introduce endogenously expressed tags has the potential to address a number of the classical limitations of single molecule localisation microscopy. In this work we present the first systematic comparison of inserts introduced through CRISPR-knock in, with the aim of optimising this approach for single molecule imaging. We show that more highly monomeric and codon optimised variants of mEos result in improved expression at the TubA1B locus, despite the use of identical guides, homology templates, and selection strategies. We apply this approach to target the G protein-coupled receptor (GPCR) CXCR4 and show a further insert dependent effect on expression and protein function. Finally, we show that compared to over-expressed CXCR4, endogenously labelled samples allow for accurate single molecule quantification on ligand treatment. This suggests that despite the complications evident in CRISPR mediated labelling, the development of CRISPR-PALM has substantial quantitative benefits

Top Quark Production and Decay at Next-to-leading Order in e+e−e^+e^- Annihilation

We study the effects of QCD corrections to the process $e^+e^-\rightarrow t\bar t+X\rightarrow b\ell^+\nu \bar b\ell^-\bar \nu+X$ above threshold. We show how to treat consistently to ${\cal O}(\alpha_s)$ the gluon radiation in both the production and the decay of the top quarks, while maintaining all angular correlations in the event. At this order there is an ambiguity in the event reconstruction whenever a real gluon occurs in the final state. We study the effects of this ambiguity on the top mass and helicity angle distributions. For a top mass of 175 GeV and collider energy of 400 GeV the gluon radiation is emitted predominantly in the decay of the top quarks.Comment: 44 pages, LaTex, 10 embedded postscript figures, tarred and uuencoded in separate fil

Implementation of the HealthKick intervention in primary schools in low-income settings in the Western Cape Province, South Africa: a process evaluation

Abstract Background The HealthKick intervention, introduced at eight primary schools in low-income settings in the Western Cape Province, South Africa, aimed to promote healthy lifestyles among learners, their families and school staff. Eight schools from similar settings without any active intervention served as controls. Methods The Action Planning Process (APP) guided school staff through a process that enabled them to assess areas for action; identify specific priorities; and set their own goals regarding nutrition and physical activity at their schools. Educators were introduced to the APP and trained to undertake this at their schools by holding workshops. Four action areas were covered, which included the school nutrition environment; physical activity and sport environment; staff health; and chronic disease and diabetes awareness. Intervention schools also received a toolkit comprising an educator’s manual containing planning guides, printed resource materials and a container with physical activity equipment. To facilitate the APP, a champion was identified at each school to drive the APP and liaise with the project team. Over the three-years a record was kept of activities planned and those accomplished. At the end of the intervention, focus group discussions were held with school staff at each school to capture perceptions about the APP and intervention activities. Results Overall uptake of events offered by the research team was 65.6 % in 2009, 75 % in 2010 and 62.5 % in 2011. Over the three-year intervention, the school food and nutrition environment action area scored the highest, with 55.5 % of planned actions being undertaken. In the chronic disease and diabetes awareness area 54.2 % actions were completed, while in the school physical activity and sport environment and staff health activity areas 25.9 and 20 % were completed respectively. According to educators, the low level of implementation of APP activities was because of a lack of parental involvement, time and available resources, poor physical environment at schools and socio-economic considerations. Conclusions The implementation of the HealthKick intervention was not as successful as anticipated. Actions required for future interventions include increased parental involvement, greater support from the Department of Basic Education and assurance of sufficient motivation and ‘buy-in’ from schools

Space, Region & Society: Geographical Essays in Honor of Robert H. Stoddard

As an expression of their friendship and esteem, the authors dedicate these essays to Robert H. Stoddard in honor of his many years of exemplary service to the people of Nebraska, the World, and the discipline of Geography. After earning the BA at Nebraska Wesleyan (1950), an MA at the University of Nebraska (1960), and the PhD at the University of Iowa (1966), Dr. Stoddard taught for some forty combined years at Nebraska Wesleyan University (1961-67) and the University of Nebraska-Lincoln (1967 to the present, where he is now Professor Emeritus). He also taught high school in India (1952-57), and was Visiting Professor at Tribhuvan University in Kathmandu, Nepal (1975-76), and the University of Columbo in Sri Lanka (1986). In addition to much productive research, many scholarly publications (notably Field Techniques and Research Methods in Geography, 1982), and unstinting university service, he also served his local community as a member of the Lincoln-Lancaster Planning Commission (1974-78). In 1992, the National Council for Geographic Education bestowed on him its Distinguished Teaching Achievement Award. Essays or chapters have been contributed by Michael R. Hill, Carl Ritter, Nainie Lenora Robertson Stoddard, Thomas Doering, Steve Kale, Carolyn V. Prorok, and Surinder M. Bhardwaj. The book includes Dr. Stoddard’s essay “Regionalization and Regionalism in Sri Lanka,” as well as a bibliography of his writings and professional papers, a chronology of publications and papers presented, and a list of dissertations and thesis supervised.https://digitalcommons.unl.edu/zeabook/1046/thumbnail.jp

Did HealthKick, a randomised controlled trial primary school nutrition intervention improve dietary quality of children in low-income settings in South Africa?

Background: Numerous studies in schools in the Western Cape Province, South Africa have shown that children have an unhealthy diet with poor diversity and which is high in sugar and fat. HealthKick (HK) was a three-year randomised controlled trial aimed at promoting healthy eating habits. Methods: Sixteen schools were selected from two low-income school districts and randomly allocated to intervention (n = 8) or control school (n = 8) status. The HK intervention comprised numerous activities to improve the school nutrition environment such as making healthier food choices available and providing nutrition education support. Dietary intake was measured by using a 24-h recall in 2009 in 500 grade 4 learners at intervention schools and 498 at control schools, and repeated in 2010 and 2011. A dietary diversity score (DDS) was calculated from nine food groups and frequency of snack food consumption was determined. A school level analysis was performed. Results: The mean baseline (2009) DDS was low in both arms 4.55 (SD = 1.29) and 4.54 (1.22) in the intervention and control arms respectively, and 49 % of learners in HK intervention schools had a DDS ≤4 (=low diversity). A small increase in DDS was observed in both arms by 2011: mean score 4.91 (1.17) and 4.83 (1.29) in the intervention and control arms respectively. The estimated DSS intervention effect over the two years was not significant [0 .04 (95 % CI: −0.37 to 0.46)]. Food groups least consumed were eggs, fruit and vegetables. The most commonly eaten snacking items in 2009 were table sugar in beverages and/or cereals (80.5 %); followed by potato crisps (53.1 %); non-carbonated beverages (42.9 %); sweets (26.7 %) and sugar-sweetened carbonated beverages (16 %). Unhealthy snack consumption in terms of frequency of snack items consumed did not improve significantly in intervention or control schools. Discussion: The results of the HK intervention were disappointing in terms of improvement in DDS and a decrease in unhealthy snacking. We attribute this to the finding that the intervention model used by the researchers may not have been the ideal one to use in a setting where many children came from low-income homes and educators have to deal with daily problems associated with poverty.Conclusions: The HK intervention did not significantly improve quality of diet of children

Whence the interstellar magnetic field shaping the heliosphere?

Measurements of starlight polarized by aligned interstellar dust grains are used to probe the relation between the orientation of the ambient interstellar magnetic field (ISMF) and the ISMF traced by the ribbons of energetic neutral atoms discovered by the Interstellar Boundary Explorer spacecraft. We utilize polarization data, many acquired specifically for this study, to trace the configuration of the ISMF within 40 pc. A statistical analysis yields a best-fit ISMF orientation, B (magpol), aligned with Galactic coordinates l = 42 degrees, b = 49 degrees. Further analysis shows the ISMF is more orderly for "downfield" stars located over 90 degrees from B (magpol). The data subset of downfield stars yields an orientation for the nearby ISMF at ecliptic coordinates lambda, beta approximate to 219 degrees +/- 15 degrees, 43 degrees +/- 9 degrees (Galactic coordinates l, b approximate to 40 degrees, 56 degrees, +/- 17 degrees). This best-fit ISMF orientation from polarization data is close to the field direction obtained from ribbon models. This agreement suggests that the ISMF shaping the heliosphere belongs to an extended ordered magnetic field. Extended filamentary structures are found throughout the sky. A previously discovered filament traversing the heliosphere nose region, "Filament A," extends over 300 degrees of the sky, and crosses the upwind direction of interstellar dust flowing into the heliosphere. Filament A overlaps the locations of the Voyager kilohertz emissions, three quasar intraday variables, cosmic microwave background (CMB) components, and the inflow direction of interstellar grains sampled by Ulysses and Galileo. These features are likely located in the upstream outer heliosheath where ISMF drapes over the heliosphere, suggesting Filament A coincides with a dusty magnetized plasma. A filament 55 degrees long is aligned with a possible shock interface between local interstellar clouds. A dark spot in the CMB is seen within 5 degrees of the filament and within 10 degrees of the downfield ISMF direction. Two large magnetic arcs are centered on the directions of the heliotail. The overlap between CMB components and the aligned dust grains forming Filament A indicates the configuration of dust entrained in the ISMF interacting with the heliosphere provides a measurable foreground to the CMB

Single-molecule experiments in biological physics: methods and applications

I review single-molecule experiments (SME) in biological physics. Recent technological developments have provided the tools to design and build scientific instruments of high enough sensitivity and precision to manipulate and visualize individual molecules and measure microscopic forces. Using SME it is possible to: manipulate molecules one at a time and measure distributions describing molecular properties; characterize the kinetics of biomolecular reactions and; detect molecular intermediates. SME provide the additional information about thermodynamics and kinetics of biomolecular processes. This complements information obtained in traditional bulk assays. In SME it is also possible to measure small energies and detect large Brownian deviations in biomolecular reactions, thereby offering new methods and systems to scrutinize the basic foundations of statistical mechanics. This review is written at a very introductory level emphasizing the importance of SME to scientists interested in knowing the common playground of ideas and the interdisciplinary topics accessible by these techniques. The review discusses SME from an experimental perspective, first exposing the most common experimental methodologies and later presenting various molecular systems where such techniques have been applied. I briefly discuss experimental techniques such as atomic-force microscopy (AFM), laser optical tweezers (LOT), magnetic tweezers (MT), biomembrane force probe (BFP) and single-molecule fluorescence (SMF). I then present several applications of SME to the study of nucleic acids (DNA, RNA and DNA condensation), proteins (protein-protein interactions, protein folding and molecular motors). Finally, I discuss applications of SME to the study of the nonequilibrium thermodynamics of small systems and the experimental verification of fluctuation theorems. I conclude with a discussion of open questions and future perspectives.Comment: Latex, 60 pages, 12 figures, Topical Review for J. Phys. C (Cond. Matt

Theory and practice – a case study of coordination and ownership in the Bangladesh health SWAp

BACKGROUND: In the past decade the sector-wide approach (SWAp) model has been promoted by donors and adopted by governments in several countries. The purpose of this study is to look at how partners involved in the health SWAp in Bangladesh define ownership and coordination, in their daily work and to analyse the possible implications of these definitions. METHODOLOGY: The study object was a process of decision-making in the Government of Bangladesh in 2003. Information was collected through participant observations, interviews and document review. RESULTS: During the study period the Government of Bangladesh decided to reverse a decision to unify the two wings of the Ministry of Health and Family Welfare. The decision led to disagreements with development partners, which had serious implications for cooperation between key actors in the Bangladesh health sector leading to deteriorated relationships and suspension of donor funds. The donor community in itself was also in disagreement which led to inconsistencies in the dialogue between the development partners and the Government of Bangladesh. CONCLUSION: The case shows that main actors in the Bangladesh health SWAp interpret ownership and coordination, fundamental aspects of SWAp, differently. As long as work ran smoothly, the different definitions did not create any problems, but when disagreements arose they became an obstacle. It is concluded that partners in development should devote more effort to their working relationships and that responsibilities within a SWAp need to be more clearly delineated