The Interdomain Linker of AAV-2 Rep68 Is an Integral Part of Its Oligomerization Domain: Role of a Conserved SF3 Helicase Residue in Oligomerization

The four Rep proteins of adeno-associated virus (AAV) orchestrate all aspects of its viral life cycle, including transcription regulation, DNA replication, virus assembly, and site-specific integration of the viral genome into the human chromosome 19. All Rep proteins share a central SF3 superfamily helicase domain. In other SF3 members this domain is sufficient to induce oligomerization. However, the helicase domain in AAV Rep proteins (i.e. Rep40/Rep52) as shown by its monomeric characteristic, is not able to mediate stable oligomerization. This observation led us to hypothesize the existence of an as yet undefined structural determinant that regulates Rep oligomerization. In this document, we described a detailed structural comparison between the helicase domains of AAV-2 Rep proteins and those of the other SF3 members. This analysis shows a major structural difference residing in the small oligomerization sub-domain (OD) of Rep helicase domain. In addition, secondary structure prediction of the linker connecting the helicase domain to the origin-binding domain (OBD) indicates the potential to form α-helices. We demonstrate that mutant Rep40 constructs containing different lengths of the linker are able to form dimers, and in the presence of ATP/ADP, larger oligomers. We further identified an aromatic linker residue (Y224) that is critical for oligomerization, establishing it as a conserved signature motif in SF3 helicases. Mutation of this residue critically affects oligomerization as well as completely abolishes the ability to produce infectious virus. Taken together, our data support a model where the linker residues preceding the helicase domain fold into an α-helix that becomes an integral part of the helicase domain and is critical for the oligomerization and function of Rep68/78 proteins through cooperative interaction with the OBD and helicase domains

Structuring effect of tools conceptualized through initial goal fixedness for work activity

Analysis of work activities in nuclear industry has highlighted a new psycho-cognitive phenomenon: the structuring effect of tools (SET) sometimes leading to unexpected operating deviations; the subject is unable to perform a task concerning object A using or adapting a tool designed and presented to perform the same task concerning object B when object A is expected by the subject. Conditions to isolate and identify the SET were determined and reproduced in experiments for further analysis. Students and seven professional categories of adults (N = 77) were involved in three experimental conditions (control group, group with prior warning, group with final control) while individually performing a task with similar characteristics compared to real operating conditions and under moderate time-pressure. The results were: (1) highest performance with prior warning and (2) demonstration that academic and professional training favor the SET. After discussing different cognitive processes potentially related to the SET, we described (3) the psycho-cognitive process underlying the SET: Initial Goal Fixedness (IGF), a combination of the anchoring of the initial goal of the activity with a focus on the features of the initial goal favored by an Einstellung effect. This suggested coping with the negative effect of the SET by impeding the IGF rather than trying to increase the subjects’ awareness at the expense of their health. Extensions to other high-risk industries were discussed

Recovery of Energy and Chrome from Leather Waste

The energy requirements for the leather tanning industry are considerable and depend primarily on nonrenewable fuels such as oil and natural gas. However, some 50 percent, approximately 1.85 x 1012 BTU/year, of the energy needed to support the U.S. tanning industry may be met through an active conservation program. This program would be directed at the recovery of the energy available in the leather waste; the raw and finished tanned leather trimmings and cuttings resulting from tannery operations. At the present time, leather waste is being disposed of in landfills. This represents an environmental problem and a significant loss of potential energy and of valuable chromium compounds that can be utilized in the tanning process. Recovery of energy and chrome compounds can result in a saving of some 25 million dollars per year for the industry. The paper presents a pyrolysis method for handling leather tanning wastes to recover energy and chromium compounds for use in the tanning process. Energy and cost savings are estimated

A systematic review of effectiveness and cost-effectiveness of school-based identification of children and young people at risk of, or currently experiencing mental health difficulties.

BACKGROUND: Although school-based programmes for the identification of children and young people (CYP) with mental health difficulties (MHD) have the potential to improve short- and long-term outcomes across a range of mental disorders, the evidence-base on the effectiveness of these programmes is underdeveloped. In this systematic review, we sought to identify and synthesise evidence on the effectiveness and cost-effectiveness of school-based methods to identify students experiencing MHD, as measured by accurate identification, referral rates, and service uptake. METHOD: Electronic bibliographic databases: MEDLINE, Embase, PsycINFO, ERIC, British Education Index and ASSIA were searched. Comparative studies were included if they assessed the effectiveness or cost-effectiveness of strategies to identify students in formal education aged 3-18 years with MHD, presenting symptoms of mental ill health, or exposed to psychosocial risks that increase the likelihood of developing a MHD. RESULTS: We identified 27 studies describing 44 unique identification programmes. Only one study was a randomised controlled trial. Most studies evaluated the utility of universal screening programmes; where comparison of identification rates was made, the comparator test varied across studies. The heterogeneity of studies, the absence of randomised studies and poor outcome reporting make for a weak evidence-base that only generate tentative conclusions about the effectiveness of school-based identification programmes. CONCLUSIONS: Well-designed pragmatic trials that include the evaluation of cost-effectiveness and detailed process evaluations are necessary to establish the accuracy of different identification models, as well as their effectiveness in connecting students to appropriate support in real-world settings.This article presents independent research funded by the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research & Care (CLAHRC) East of England, at Cambridgeshire and Peterborough NHS Foundation Trust, and CLAHRC South West. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care