Focus on function: Single molecule RNA enzymology

The ability of RNA to catalyze chemical reactions was first demonstrated 25 years ago with the discovery that group I introns and RNase P function as RNA enzymes (ribozymes). Several additional ribozymes were subsequently identified, most notably the ribosome, followed by intense mechanistic studies. More recently, the introduction of single molecule tools has dissected the kinetic steps of several ribozymes in unprecedented detail and has revealed surprising heterogeneity not evident from ensemble approaches. Still, many fundamental questions of how RNA enzymes work at the molecular level remain unanswered. This review surveys the current status of our understanding of RNA catalysis at the single molecule level and discusses the existing challenges and opportunities in developing suitable assays. © 2007 Wiley Periodicals, Inc. Biopolymers 87: 302–316, 2007. This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at [email protected] Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/57325/1/20819_ftp.pd

Unhealthy Snack Food and Beverage Consumption Is Associated with Lower Dietary Adequacy and Length-for-Age z-Scores among 12-23-Month-Olds in Kathmandu Valley, Nepal.

BACKGROUND: Consumption of unhealthy snack foods and beverages (USFBs) in low- and middle-income countries (LMICs) is rising, with global awareness increasing about risks of overnutrition. However, little is known about the relation between USFB consumption and young children's diet/nutritional outcomes in contexts where nutrient density of complementary foods is often low. OBJECTIVES: This study assessed the association of high USFB consumption, compared with low consumption, with nutrient intakes, dietary adequacy, iron status, and growth in young children in Kathmandu Valley, Nepal. METHODS: A cross-sectional survey was conducted in a representative sample of 745 primary caregivers of children aged 12-23 mo. Food consumption was measured through quantitative 24-h recalls, and child anthropometric measurements and capillary blood samples were collected. Using adjusted linear/logistic regression models, nutrient intakes, dietary adequacy, length-for-age and weight-for-length z-scores (LAZ and WLZ, respectively), and iron status were compared between lowest and highest tertiles of consumption based on the contribution of USFBs to total energy intakes (TEIs). Mediation of the relation between USFB consumption and LAZ via lowered dietary adequacy was explored using structural equations modeling. RESULTS: On average, USFBs contributed 46.9% of TEI among the highest tertile of consumers, compared with 5.2% of TEI among the lowest. Compared with low-USFB consumers, high-USFB consumers had lower nutrient intakes and a greater proportion were at risk of inadequate intakes for 8 nutrients. Mean LAZ was nearly 0.3 SD lower among high-USFB consumers than low consumers (P = 0.003), with this relationship partially mediated through dietary adequacy. No associations were found with stunting prevalence or iron status. Prevalence of overweight/obesity was low. CONCLUSIONS: In this LMIC context, high USFB consumption among young children was associated with inadequate micronutrient intakes, which can contribute to poor growth outcomes. Addressing increased availability of USFBs in LMIC food systems should be a priority for policies and programs aiming to safeguard child nutrition

Musculoskeletal Pain Is Impacted by Job Tasks in Temporary Construction Workers Hired Through Construction Staffing Agencies

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950 Health and safety of temporary construction workers: evidence from teaching temporary employees about competencies in health and safety (tteachs) study

Introduction Despite the high-risk nature of construction jobs, this blue-collar workforce continues to provide unique opportunities for contingent (e.g., temporary) work. Compared to payroll workers, there is evidence suggesting temporary construction workers have a relatively higher risk of being injured at work, which may in part be as a result of inadequate safety training, high job demands, and low job control. Using a semi-structured focus group script, we collect qualitative data to characterise the workplace health and safety experiences, attitudes, and perceptions of temporary workers employed in the construction industry. Methods Eight focus groups with 7–10 temporary construction workers per group will be conducted. The discussions will be conducted in English or Spanish and will be audio recorded and transcribed. Data collection began in March 2017 and will conclude July 2017. Focus group audio files will be transcribed verbatim and analysed using a general inductive approach to identify emergent themes. Result Preliminary findings indicate that participating temporary workers (n=20) were mostly male (95.0%), non-Hispanic (84.2%), Black/African American (78.9%) with a mean age of 42.8 years (standard deviation [SD]=11.9), and employed as a temporary construction worker for an average of 2.9 years (SD=2.4). Among all participants, 40% had been injured at the construction site in the past 12 months, 52.6% reported receiving safety training at the start of their job, and 41.2% were trained when asked to conduct new job tasks. Major themes that emerged included: assessment of jobsite risk at the worker- and organizational- level; visual safety cues in risk assessment process; worksite protective factors. Discussion Temporary construction workers in this ongoing pilot study reported high rates of worksite injuries. Strategies to improve training opportunities for temporary construction workers during new jobsite orientation and upon being asked to complete new job tasks are needed