2,426 research outputs found

    Aphid Thermal Tolerance Is Governed by a Point Mutation in Bacterial Symbionts

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    Symbiosis is a ubiquitous phenomenon generating biological complexity, affecting adaptation, and expanding ecological capabilities. However, symbionts, which can be subject to genetic limitations such as clonality and genomic degradation, also impose constraints on hosts. A model of obligate symbiosis is that between aphids and the bacterium Buchnera aphidicola, which supplies essential nutrients. We report a mutation in Buchnera of the aphid Acyrthosiphon pisum that recurs in laboratory lines and occurs in field populations. This single nucleotide deletion affects a homopolymeric run within the heat-shock transcriptional promoter for ibpA, encoding a small heat-shock protein. This Buchnera mutation virtually eliminates the transcriptional response of ibpA to heat stress and lowers its expression even at cool or moderate temperatures. Furthermore, this symbiont mutation dramatically affects host fitness in a manner dependent on thermal environment. Following a short heat exposure as juveniles, aphids bearing short-allele symbionts produced few or no progeny and contained almost no Buchnera, in contrast to aphids bearing symbionts without the deletion. Conversely, under constant cool conditions, aphids containing symbionts with the short allele reproduced earlier and maintained higher reproductive rates. The short allele has appreciable frequencies in field populations (up to 20%), further supporting the view that lowering of ibpA expression improves host fitness under some conditions. This recurring Buchnera mutation governs thermal tolerance of aphid hosts. Other cases in which symbiont microevolution has a major effect on host ecological tolerance are likely to be widespread because of the high mutation rates of symbiotic bacteria and their crucial roles in host metabolism and development

    Effectiveness and cost-effectiveness of a universal parenting skills programme in deprived communities : multicentre randomised controlled trial

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    Objective: To evaluate the effectiveness and cost utility of a universally provided early years parenting programme. Design: Multicentre randomised controlled trial with cost-effectiveness analysis. Setting: Early years centres in four deprived areas of South Wales. Participants: Families with children aged between 2 and 4 years. 286 families were recruited and randomly allocated to the intervention or waiting list control. Intervention: The Family Links Nurturing Programme (FLNP), a 10-week course with weekly 2 h facilitated group sessions. Main outcome measures: Negative and supportive parenting, child and parental well-being and costs assessed before the intervention, following the course (3 months) and at 9 months using standardised measures. Results: There were no significant differences in primary or secondary outcomes between trial arms at 3 or 9 months. With ‘+’ indicating improvement, difference in change in negative parenting score at 9 months was +0.90 (95%CI −1.90 to 3.69); in supportive parenting, +0.17 (95%CI −0.61 to 0.94); and 12 of the 17 secondary outcomes showed a non-significant positive effect in the FLNP arm. Based on changes in parental well-being (SF-12), the cost per quality-adjusted life year (QALY) gained was estimated to be £34 913 (range 21 485–46 578) over 5 years and £18 954 (range 11 664–25 287) over 10 years. Probability of cost per QALY gained below £30 000 was 47% at 5 years and 57% at 10 years. Attendance was low: 34% of intervention families attended no sessions (n=48); only 47% completed the course (n=68). Also, 19% of control families attended a parenting programme before 9-month follow-up. Conclusions: Our trial has not found evidence of clinical or cost utility for the FLNP in a universal setting. However, low levels of exposure and contamination mean that uncertainty remains. Trial registration: The trial is registered with Current Controlled Trials ISRCTN13919732

    Lagrangian Decomposition of the Atlantic Ocean Heat Transport at 26.5°N

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    The Atlantic Meridional Overturning Circulation (AMOC) plays a critical role in the global climate system through the redistribution of heat, freshwater and carbon. At 26.5°N, the meridional heat transport has traditionally been partitioned geometrically into vertical and horizontal circulation cells; however, attributing these components to the AMOC and Subtropical Gyre (STG) flow structures remains widely debated. Using water parcel trajectories evaluated within an eddy‐rich ocean hindcast, we present the first Lagrangian decomposition of the meridional heat transport at 26.5°N. We find that water parcels recirculating within the STG account for 37% (0.36 PW) of the total heat transport across 26.5°N, more than twice that of the classical horizontal gyre component (15%). Our findings indicate that STG heat transport cannot be meaningfully distinguished from that of the basin‐scale overturning since water parcels cooled within the gyre subsequently feed the northward, subsurface limb of the AMOC

    The Iowa Homemaker vol.2, no.5-6

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    Table of Contents Your Child Between the Bottle and School Age by Belle Lowe, page 1 Buy Your Hat From Your Grocery Savings by Blanche Ingersoll, page 2 Has Hosiery Become Your Hobby? by Mildred B. Elder, page 3 Pottery Making as a Community Work by Paul E. Cox, page 4 Fall Forecast for Children’s Frocks by Helen Paschal, page 5 “Ye Hatte Shoppe” As a Summer’s Occupation by Ruth Wilson, page 6 Will Courtesy Count in Your Child’s Career? by Eda Lord Murphy, page 7 Who’s There and Where by Jeanette Beyer, page 10 Card File Your Foreign Terms by Eleanor Murphy, page 10 Rival the Orient With Sealing Wax by Opal Wind, page 11 “Back to Natur”-ing With a Camp Kit by Helen T. Peterson, page 12 The Art of Outcasting Flies by Dorothy Morris, page 1

    Improving response rates using a monetary incentive for patient completion of questionnaires: an observational study

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    Background: Poor response rates to postal questionnaires can introduce bias and reduce the statistical power of a study. To improve response rates in our trial in primary care we tested the effect of introducing an unconditional direct payment of 5 pound for the completion of postal questionnaires. Methods: We recruited patients in general practice with knee problems from sites across the United Kingdom. An evidence-based strategy was used to follow-up patients at twelve months with postal questionnaires. This included an unconditional direct payment of 5 pound to patients for the completion and return of questionnaires. The first 105 patients did not receive the 5 pound incentive, but the subsequent 442 patients did. We used logistic regression to analyse the effect of introducing a monetary incentive to increase the response to postal questionnaires. Results: The response rate following reminders for the historical controls was 78.1% ( 82 of 105) compared with 88.0% ( 389 of 442) for those patients who received the 5 pound payment (diff = 9.9%, 95% CI 2.3% to 19.1%). Direct payments significantly increased the odds of response ( adjusted odds ratio = 2.2, 95% CI 1.2 to 4.0, P = 0.009) with only 12 of 442 patients declining the payment. The incentive did not save costs to the trial - the extra cost per additional respondent was almost 50 pound. Conclusion: The direct payment of 5 pound significantly increased the completion of postal questionnaires at negligible increase in cost for an adequately powered study

    Gene pathway development in human epicardial adipose tissue during early life

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    Studies in rodents and newborn humans demonstrate the influence of brown adipose tissue (BAT) in temperature control and energy balance and a critical role in the regulation of body weight. Here, we obtained samples of epicardial adipose tissue (EAT) from neonates, infants, and children in order to evaluate changes in their transcriptional landscape by applying a systems biology approach. Surprisingly, these analyses revealed that the transition to infancy is a critical stage for changes in the morphology of EAT and is reflected in unique gene expression patterns of a substantial proportion of thermogenic gene transcripts (~10%). Our results also indicated that the pattern of gene expression represents a distinct developmental stage, even after the rebound in abundance of thermogenic genes in later childhood. Using weighted gene coexpression network analyses, we found precise anthropometric-specific correlations with changes in gene expression and the decline of thermogenic capacity within EAT. In addition, these results indicate a sequential order of transcriptional events affecting cellular pathways, which could potentially explain the variation in the amount, or activity, of BAT in adulthood. Together, these results provide a resource to elucidate gene regulatory mechanisms underlying the progressive development of BAT during early life

    The Iowa Homemaker vol.3, no.3-4

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    Table of Contents The Architectural Design of a Home by Allen Holmes Kimball, page 1 “For a Man’s House Is His Castle” by Alda Wilson, page 2 The Economics of Consumption compiled by John E. Brindley, page 3 Sunfast and Tubfast Materials by Pearl Apland, page 5 On Our Street by Juanita J. Beard, page 6 Who Is Responsible for the Child? by Orange H. Cessna, page 7 Summer Suppers by N. Beth Bailey, page 8 Vacation First Aid by Dr. Mary Sheldon, page 9 Episodes Concerning Evolution of Home Economics by Ruth Elaine Wilson, page 10 Extravagant Economics by Blanche Ingersoll, page 11 Breakfast Bridge by Eleanor Murray, page 12 Veishea Celebrates First Birthday by Helen G. Lamb, page 1

    The Iowa Homemaker vol.3, no.11

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    Table of Contents Identity by Ruth Elaine Wilson, page 2 The Responsibility of American Women to Citizenship by Marcia M. Roberts, page 3 Hearth and Home by Amanda Jacobsen, page 4 A Parent “That Needeth Not to be Ashamed” by Thomas F. Vance, page 5 Corn – Greatest Crop of Iowa by Gertrude E. Murray, page 6 American Home Economics Association Meets by Lela Johnson, page 7 The Evolution of Home Economics at Iowa State by Ruth Elaine Wilson, page 7 Hints for the Spring Wardrobe by Grace L. Heidbreder and Helen Brennan, page 8 Etiquette for College Girl by Marcella Dewell, page 9 Who’s There and Where by Dryden Quist, page 1
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