A proposed concept for a crustal dynamics information management network

The findings of a requirements and feasibility analysis of the present and potential producers, users, and repositories of space-derived geodetic information are summarized. A proposed concept is presented for a crustal dynamics information management network that would apply state of the art concepts of information management technology to meet the expanding needs of the producers, users, and archivists of this geodetic information

Srs2 Disassembles Rad51 Filaments by a Protein-Protein Interaction Triggering ATP Turnover and Dissociation of Rad51 from DNA

Rad51 is a DNA recombinase functioning in the repair of DNA double-strand breaks and the generation of genetic diversity by homologous recombination (HR). In the presence of ATP, Rad51 self-assembles into an extended polymer on single-stranded DNA to catalyze strand exchange. Inappropriate HR causes genomic instability, and it is normally prevented by remodeling enzymes that antagonize the activities of Rad51 nucleoprotein filaments. In yeast, the Srs2 helicase/translocase suppresses HR by clearing Rad51 polymers from single-stranded DNA. We have examined the mechanism of disassembly of Rad51 nucleoprotein filaments by Srs2 and find that a physical interaction between Rad51 and the C-terminal region of Srs2 triggers ATP hydrolysis within the Rad51 filament, causing Rad51 to dissociate from DNA. This allosteric mechanism explains the biological specialization of Srs2 as a DNA motor protein that antagonizes HR

Positive Youth Development Life Skills Gained at the Iowa 4-H Youth Conference

Research suggests 4-H programs build Life Skills such as leadership, communication, citizenship and learning. However, 4-H programs vary from long-term on-going experiences to shorter, more intense opportunities. This paper discusses a program evaluation articulating the life skill development of participants in a 3-day residential State 4-H Conference on a Midwestern college campus. The Life Skills assessed were in the areas of leadership, citizenship, communication, and learning as part of overall Life Skill development. Participants were youth ages 14-18 years. A retrospective pretest-posttest was used to evaluate skill development and understanding. Analysis, including paired sample t-tests, indicated growth in each of the 12 common outcome measures evaluated. This study supports the importance of purposeful planning and youth engagement in the learning process to achieve desired life skill outcomes

Creating School-Family Partnerships in Adolescence: Challenges and Opportunities

Adolescence is a time of rapid change. These changes present challenges and opportunities for developing youth including physical changes, significant cognitive advancements, emotional maturation, and new peer and romantic relationships. For most adolescents, these changes are also accompanied by changes in their environments including more demanding expectations for independence, more challenging academic tasks, and new expectations for social participation from parents and peers. At the same time, adolescents are becoming more independent from their families while also maintaining a sense of connection to them and to their schools

Ensemble Methods for Monitoring Enzyme Translocation along Single Stranded Nucleic Acids

We review transient kinetic methods developed to study the mechanism of translocation of nucleic acid motor proteins. One useful stopped-flow fluorescence method monitors arrival of the translocase at the end of a fluorescently labeled nucleic acid. When conducted under single-round conditions the time courses can be analyzed quantitatively using n-step sequential models to determine the kinetic parameters for translocation (rate, kinetic step size and processivity). The assay and analysis discussed here can be used to study enzyme translocation along a linear lattice such as ssDNA or ssRNA. We outline the methods for experimental design and two approaches, along with their limitations, that can be used to analyze the time courses. Analysis of the full time courses using n-step sequential models always yields an accurate estimate of the translocation rate. An alternative semi-quantitative “time to peak” analysis yields accurate estimates of translocation rates only if the enzyme initiates translocation from a unique site on the nucleic acid. However, if initiation occurs at random sites along the nucleic acid, then the “time to peak” analysis can yield inaccurate estimates of even the rates of translocation depending on the values of other kinetic parameters, especially the rate of dissociation of the translocase. Thus, in those cases analysis of the full time course is needed to obtain accurate estimates of translocation rates

Single stranded DNA translocation of E. coli UvrD monomer is tightly coupled to ATP hydrolysis

E. coli UvrD is an SF1A helicase/translocase that functions in several DNA repair pathways. A UvrD monomer is a rapid and processive single-stranded (ss) DNA translocase, but is unable to unwind DNA processively in vitro. Based on data at saturating ATP (500 μM) we proposed a non-uniform stepping mechanism in which a UvrD monomer translocates with biased (3′ to 5′) directionality while hydrolyzing 1 ATP per DNA base translocated, but with a kinetic step-size of 4–5 nucleotides/step, suggesting a pause occurs every 4–5 nucleotides translocated. To further test this mechanism we examined UvrD translocation over a range of lower ATP concentrations (10–500 μM ATP), using transient kinetic approaches. We find a constant ATP coupling stoichiometry of ~1 ATP/DNA base translocated even at the lowest ATP concentration examined (10 μM) indicating that ATP hydrolysis is tightly coupled to forward translocation of a UvrD monomer along ssDNA with little slippage or futile ATP hydrolysis during translocation. The translocation kinetic step size remains constant at 4–5 nucleotides/step down to 50 μM ATP, but increases to ~7 nucleotides/step at 10 μM ATP. These results suggest that UvrD pauses more frequently during translocation at low ATP, but with little futile ATP hydrolysis

Predictors and Consequences of Anaemia Among Antiretroviral-Naïve HIV-Infected and HIV-Uninfected Children in Tanzania.

Predictors and consequences of childhood anaemia in settings with high HIV prevalence are not well known. The aims of the present study were to identify maternal and child predictors of anaemia among children born to HIV-infected women and to study the association between childhood anaemia and mortality. Prospective cohort study. Maternal characteristics during pregnancy and Hb measurements at 3-month intervals from birth were available for children. Information was also collected on malaria and HIV infection in the children, who were followed up for survival status until 24 months after birth. Dar es Salaam, Tanzania. The study sample consisted of 829 children born to HIV-positive women. Advanced maternal clinical HIV disease (relative risk (RR) for stage > or =2 v. stage 1: 1.31, 95 % CI 1.14, 1.51) and low CD4 cell counts during pregnancy (RR for <350 cells/mm3 v. > or =350 cells/mm3: 1.58, 95 % CI 1.05, 2.37) were associated with increased risk of anaemia among children. Birth weight <2500 g, preterm birth (<34 weeks), malaria parasitaemia and HIV infection in the children also increased the risk of anaemia. Fe-deficiency anaemia in children was an independent predictor of mortality in the first two years of life (hazard ratio 1.99, 95 % CI 1.06, 3.72). Comprehensive care including highly active antiretroviral therapy to eligible HIV-infected women during pregnancy could reduce the burden of anaemia in children. Programmes for the prevention of mother-to-child transmission of HIV and antimalarial treatment to children could improve child survival in settings with high HIV prevalence

Harsh Parenting and Food Insecurity in Adolescence: The Association with Emerging Adult Obesity

In the U.S., as of 2012, more than one in three youth were overweight or obese [1]. This is a critical health issue, as being overweight or obese (OW/OB) during adolescence increases the risk of adulthood diseases, including but not limited to cardiovascular and heart disease, diabetes, stroke, cancer, and osteoarthritis [2]. Understanding the pathways to obesity is critical for implementation of successful prevention and intervention programs. One of the pathways leading to OW/OB is through social and economic experiences within the family

The Influence of Parental Alcoholism on Parent–Adolescent Relationships From Adolescence Into Emerging Adulthood: A Qualitative Inquiry

Exposure to parental alcoholism can inhibit a child’s ability to become a successfully functioning young adult. Based on qualitative interviews, this study provides a deeper understanding of how those parent–adolescent relationships are associated with risky internalizing and externalizing behaviors. This qualitative study explores the lives of 13 young adult children of alcoholics (ACOAs) and provides a unique perspective through an adaptive developmental approach by evaluating emerging adults who were ACOAs and successfully functioning. Compelling findings emerged with respect to how young adults define alcoholism and being a child of alcoholism and how the parent–adolescent relationship adapts in the unstable environment associated with family alcoholism. Salient findings revealed that when emotional and physical detachment from a parent’s alcoholic behaviors in addition to an acceptance that those behaviors are not the adolescent’s responsibility, individuals gained better control of their environment aiding them in becoming healthy, functioning young adults