Intrinsic and extrinsic factors drive ontogeny of early-life at-sea behaviour in a marine top predator

Young animals must learn to forage effectively to survive the transition from parental provisioning to independent feeding. Rapid development of successful foraging strategies is particularly important for capital breeders that do not receive parental guidance after weaning. The intrinsic and extrinsic drivers of variation in ontogeny of foraging are poorly understood for many species. Grey seals (Halichoerus grypus) are typical capital breeders; pups are abandoned on the natal site after a brief suckling phase, and must develop foraging skills without external input. We collected location and dive data from recently-weaned grey seal pups from two regions of the United Kingdom (the North Sea and the Celtic and Irish Seas) using animal-borne telemetry devices during their first months of independence at sea. Dive duration, depth, bottom time, and benthic diving increased over the first 40 days. The shape and magnitude of changes differed between regions. Females consistently had longer bottom times, and in the Celtic and Irish Seas they used shallower water than males. Regional sex differences suggest that extrinsic factors, such as water depth, contribute to behavioural sexual segregation. We recommend that conservation strategies consider movements of young naïve animals in addition to those of adults to account for developmental behavioural changes

Lifetime corneal edema load model

Purpose: To highlight the potential benefits for long-term use of silicone hydrogels daily disposable (DD) contact lenses, particularly with patients who are noncompliant, sleeping or napping while wearing their lenses, or those who have higher oxygen demands and wear this modality for decades. Methods: Published data for corneal swelling with lenses and no lens wear were used to develop a nonlinear least squares model. The edema load experienced with a range of oxygen transmissibilities (Dk/t) and wear compliance (sleep and napping) was determined. A mixed-effects linear regression model was used to compare the edema load for high and average corneal swellers. Results: The edema load generated demonstrates that a high Dk/t silicone hydrogel lens results in edema levels close to that with no lens wear. In comparison, hydrogels with a Dk/t of 27 (×10−9 [cm mL{O2}][s mLmmHg]), worn on a daily wear schedule will result in 1.5 times more edema and up to two times more if the patient is noncompliant over each decade of wear. High swellers after four decades of wear will have an edema load 10 to 17 times greater than average swellers depending on Dk/t and their degree of noncompliance with the daily wear modality. Conclusions: Prescribing silicone hydrogelDDlenses, particularly with higher DK/t,may help to maintain the long-term ocular health of patients, when they wear their lenses fulltime for many decades. Translational Relevance: Illustrates the importance of Dk/t for any CL wear modality where patients nap or sleep in lenses or have high oxygen needs

Propionibacterium acnes bacteriophages display limited genetic diversity and broad killing activity against bacterial skin isolates.

UnlabelledInvestigation of the human microbiome has revealed diverse and complex microbial communities at distinct anatomic sites. The microbiome of the human sebaceous follicle provides a tractable model in which to study its dominant bacterial inhabitant, Propionibacterium acnes, which is thought to contribute to the pathogenesis of the human disease acne. To explore the diversity of the bacteriophages that infect P. acnes, 11 P. acnes phages were isolated from the sebaceous follicles of donors with healthy skin or acne and their genomes were sequenced. Comparative genomic analysis of the P. acnes phage population, which spans a 30-year temporal period and a broad geographic range, reveals striking similarity in terms of genome length, percent GC content, nucleotide identity (>85%), and gene content. This was unexpected, given the far-ranging diversity observed in virtually all other phage populations. Although the P. acnes phages display a broad host range against clinical isolates of P. acnes, two bacterial isolates were resistant to many of these phages. Moreover, the patterns of phage resistance correlate closely with the presence of clustered regularly interspaced short palindromic repeat elements in the bacteria that target a specific subset of phages, conferring a system of prokaryotic innate immunity. The limited diversity of the P. acnes bacteriophages, which may relate to the unique evolutionary constraints imposed by the lipid-rich anaerobic environment in which their bacterial hosts reside, points to the potential utility of phage-based antimicrobial therapy for acne.ImportancePropionibacterium acnes is a dominant member of the skin microflora and has also been implicated in the pathogenesis of acne; however, little is known about the bacteriophages that coexist with and infect this bacterium. Here we present the novel genome sequences of 11 P. acnes phages, thereby substantially increasing the amount of available genomic information about this phage population. Surprisingly, we find that, unlike other well-studied bacteriophages, P. acnes phages are highly homogeneous and show a striking lack of genetic diversity, which is perhaps related to their unique and restricted habitat. They also share a broad ability to kill clinical isolates of P. acnes; phage resistance is not prevalent, but when detected, it appears to be conferred by chromosomally encoded immunity elements within the host genome. We believe that these phages display numerous features that would make them ideal candidates for the development of a phage-based therapy for acne

Objectively Measured Physical Activity in Sixth-Grade Girls

Objectives - To describe the objectively-measured physical activity (PA) characteristics of a diverse sample of 6th grade girls to examine influences on PA, and to report compliance with PA guidelines. Design - Cross-sectional study. Setting - Six locations across the United States. Participants - 1578 6th grade girls. Actigraph accelerometers were worn for 7 days, and data for 6 days were included in the analyses. Main exposure - Race/ethnicity, free-or-reduced price lunch (FRPL), and geographic region. Main outcome measure - Six operational definitions of adequate activity (60 min or 30 min of daily MVPA at or above 4.6, 3.8 or 3.0 METS (metabolic equivalents)) were applied to examine whether girls met physical activity guidelines. Results - Average time spent in sedentary, light, moderate, and vigorous activities was 460, 342, 18, and 6 min/day, respectively. White girls were more active than girls in other race/ethnic groups, and girls who did not receive FRPL were more active than girls who did. Girls in western states were most active. Percentages of girls in compliance with the 6 thresholds for adequate activity varied widely, and ranged from 0.6% to 99.8%. Conclusions - When physical activity is measured objectively and a 4.6 MET cupoint for MVPA is applied, most 6th grade girls fall below guidelines for adequate physical activity. One notable finding was the impact of different accelerometer scoring protocols on estimates of compliance. Conceptual and empirical work is needed to define appropriate physical activity for youth using objective physical activity measures

Ready or not: employment, re-entry and the lasting effects of stigma after incarceration

In this thesis I explore the how former prisoners experience the transition from incarceration to employment. Employment has been identified by researchers as an essential element in exprisoners’ community re-entry process. However, the path to attaining employment after incarceration, particularly meaningful employment, remains complicated. Drawing on in-depth, semi-structured longitudinal interviews with 24 parolees occurring over a three-year period, I seek to better understand the experiences of ex-prisoners as they attempt to find work. I aim to understand whether individuals are prepared to pursue employment immediately upon release from prison and the factors that impact their readiness, or lack thereof. Upon recognizing that individuals in the study tended to identify themselves as not ready for employment, I sought to understand why they were still expected to begin working using Goffman’s (1963) theory of stigma. I suggest that in many cases, attempting to manage one’s stigmatized status slows individuals’ return to work. As well, I suggest that the stigma associated with time spent incarcerated undermines individual credibility, and for this reason, participants’ assertions that they do not feel ready to begin working are often not accepted

Comparison of Two Approaches to Structured Physical Activity Surveys of Adolescents

Purpose - To compare the test-retest reliability, convergent validity, and overall feasibility/usability of activity-based (AB) and time-based (TB) approaches for obtaining self-reported moderate-to-vigorous physical activity (MVPA) from adolescents. Methods - Adolescents (206 females and 114 males) completed two 3-d physical activity recalls using the AB and TB surveys, which contained identical lists of physical activities. The participants wore an MTI Actigraph® accelerometer for the same period. Results - The TB instrument took about 3 min longer to complete (P=0.022). Overall 2-d test-retest correlations for MVPA were similar for the two surveys (r=0.676 and 0.667), but the girls had higher reliability on the AB survey than the boys (girls: r=0.713; boys: r=0.568). The overall 3-d correlations for MVPA surveys and Actigraph counts varied by gender (girls: AB=0.265 vs TB=0.314; boys: AB=0.340 vs TB=0.277). Correlations for vigorous physical activity and Actigraph counts were higher for the AB than for the TB (r=0.281 vs 0.162). As the interval between completing the surveys and the days being recalled increased, reliability and validity were lower, especially for the AB survey. Conclusion - For both genders, either approach is acceptable for obtaining MVPA information on a single day, but the TB approach appears to be slightly favored over the AB approach for obtaining multiple days of MVPA. A 3-d recall period appears to be too long for accurate recall of MVPA information from either instrument. For both genders, the surveys overestimate activity levels; thus, self-reports should be supplemented with objective data

Age-Related Changes in Types and Contexts of Physical Activity in Middle School Girls

Background - Because girls are less physically active than boys, it is important to understand the types of activities preferred by girls, and changes in those preferences over time, in order to design effective physical activity interventions. Purpose - To describe developmental trends in participation in specific forms of physical activity in 6th- and 8th-grade girls. Methods - Data for this study are from the Trial of Activity for Adolescent Girls. Self-reported physical activity, anthropometric, and demographic data were collected from random cross sections of 6th-grade girls in 36 middle schools in six U.S. communities. The same data were collected 2 years later from random cross sections of 8th-grade girls, as well as in previously measured 6th-grade girls who remained in the schools. Analyses were conducted with SAS using mixed model ANOVAs to determine differences between 6th- and 8th-grade girls. Data were collected in 2002-2003 and 2004-2005 and analyzed in 2008-2009. Results - The top physical activities reported by 6th- and 8th-grade girls were similar. Of the top 13 activities reported by 6th- or 8th-grade girls, 8th-grade girls reported participating in more 30-minute blocks for 10 of the activities and were more likely to report participating as part of an organized program. Conclusions - The activities reported by 6th- and 8th-grade girls were similar, but the way they participated in them changed from 6th to 8th grade. Eighth-grade girls were more likely to participate in activities that are often part of school-based team sports, and the time of participation in these activities was greater. Interventions to increase physical activity in adolescent girls should be informed by the factors that influence their participation in organized school sports programs and community-based activities that promote physical activity

Age-Related Changes in Types and Contexts of Physical Activity in Middle School Girls

Because girls are less physically active than boys, it is important to understand the types of activities preferred by girls, and changes in those preferences over time, in order to design effective physical activity interventions

Cluster M Mycobacteriophages Bongo, PegLeg, and Rey with Unusually Large Repertoires of tRNA Isotopes

Genomic analysis of a large set of phages infecting the common hostMycobacterium smegmatis mc2155 shows that they span considerable genetic diversity. There are more than 20 distinct types that lack nucleotide similarity with each other, and there is considerable diversity within most of the groups. Three newly isolated temperate mycobacteriophages, Bongo, PegLeg, and Rey, constitute a new group (cluster M), with the closely related phages Bongo and PegLeg forming subcluster M1 and the more distantly related Rey forming subcluster M2. The cluster M mycobacteriophages have siphoviral morphologies with unusually long tails, are homoimmune, and have larger than average genomes (80.2 to 83.7 kbp). They exhibit a variety of features not previously described in other mycobacteriophages, including noncanonical genome architectures and several unusual sets of conserved repeated sequences suggesting novel regulatory systems for both transcription and translation. In addition to containing transfer-messenger RNA and RtcB-like RNA ligase genes, their genomes encode 21 to 24 tRNA genes encompassing complete or nearly complete sets of isotypes. We predict that these tRNAs are used in late lytic growth, likely compensating for the degradation or inadequacy of host tRNAs. They may represent a complete set of tRNAs necessary for late lytic growth, especially when taken together with the apparent lack of codons in the same late genes that correspond to tRNAs that the genomes of the phages do not obviously encode