Iron testes: sperm mitochondria as a context for dissecting iron metabolism

A recent paper in BMC Developmental Biology reports that a mitochondrial iron importer is required for Drosophila male fertility and normal mitochondrial shaping in spermatids. This suggests that mitochondrial morphogenesis during insect spermatogenesis may be a useful new context in which to study iron metabolism

Screening for offenders with an intellectual disability: The validity of the Learning Disability Screening Questionnaire

The study assessed the validity of an intellectual disability screening tool, the Learning Disability Screening Questionnaire (LDSQ), in three forensic settings: a community intellectual disability forensic service; a forensic in-patient secure unit and a prison, using data for 94 individuals. A significant positive relationship was found between full scale IQ and LDSQ score, indicating convergent validity. Discriminative validity was indicated by, firstly, a significant difference in the LDSQ scores between those with and without an intellectual disability, with those with a diagnosis of intellectual disability, scoring significantly lower. Secondly, a ROC analysis indicated that the sensitivity and specificity of the LDSQ were both above 80%. The screening tool was found to have lower sensitivity in the forensic populations than was obtained in the original community standardisation sample, but had slightly higher specificity. Limitations and implications of the study are discussed

Police practitioner views on the challenges of analysing and responding to knife crime

Knife crime remains a major concern in England and Wales. Problem-oriented and public health approaches to tackling knife crime have been widely advocated, but little is known about how these approaches are understood and implemented by police practitioners. To address this knowledge gap, this article draws on semi-structured interviews and focus groups with 44 police personnel to consider the processes and challenges of applying problem-oriented and public health approaches to knife crime. Findings show that knife crime was seen as a complex social problem which would not be solved by ‘silver bullets’; prevention was prioritised and the limitations of enforcement were widely acknowledged; there was an emphasis on understanding and responding to vulnerability and risk; discussion of ‘holistic’ and ‘whole systems’ approaches was evident (but these concepts were rarely defined); and the problem of serious violence was viewed as a shared, multi-agency issue that the police could not tackle alone. Various challenges were also evident, most notably around analysis of the drivers and patterns of knife crime and the evaluation of knife crime interventions. The article concludes by discussing the implications of the findings for knife crime prevention and the implementation and advancement of problem-oriented and public health approaches to policing

Characterization of a mutant polyoma that expresses in F9 embryonal carcinoma cells: Morphology, tumorigenicity, and restriction enzyme analysis

A mutant polyoma virus (TT340), which replicates in F9 embryonal carcinoma (EC) cells and contains 2500 base pairs (bp) of additional DNA located in the early noncoding region of the genome, was analyzed to determine the DNA origin of the mutant insertion. Two fragments, representing repeated units of the 2500-bp insert, were isolated from TT340, labeled, and hybridized to the parental wild-type viral DNA. A BglI 500-bp unit, of which there are approximately five copies within the 2500-bp insert, contains sequences homologous to regions on the early and late side of the viral origin of replication. A HpaII 400-bp repeated fragment shows homology to sequences on the early side with little hybridization to the late side. Removal of the 2500-bp insert results in the loss of infectivity on F9 EC cells but not on 3T6 or mouse embryo fibroblasts. Insertion of the BglI 500-bp repeat element into wild-type DNA at the BglI site allows replication of the constructed virus in F9 cells. The mutant virions were tumorigenic in newborn Syrian hamsters and the morphology of the virus was that of wild-type as assayed by electron microscopy.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26615/1/0000156.pd

Impacts of Coastal Acidification on the Pacific Northwest Shellfish Industry and Adaptation Strategies Implemented in Response

In 2007, the US west coast shellfish industry began to feel the effects of unprecedented levels of larval mortality in commercial hatcheries producing the Pacific oyster Crassostrea gigas. Subsequently, researchers at Whiskey Creek Shellfish Hatchery, working with academic and government scientists, showed a high correlation between aragonite saturation state (Ω[subscript]arag) of inflowing seawater and survival of larval groups, clearly linking increased CO₂ to hatchery failures. This work led the Pacific Coast Shellfish Growers Association (PCSGA) to instrument shellfish hatcheries and coastal waters, establishing a monitoring network in collaboration with university researchers and the US Integrated Ocean Observing System. Analytical developments, such as the ability to monitor Ω[subscript]arag in real time, have greatly improved the industry’s understanding of carbonate chemistry and its variability and informed the development of commercial-scale water treatment systems. These treatment systems have generally proven effective, resulting in billions of additional oyster larvae supplied to Pacific Northwest oyster growers. However, significant challenges remain, and a multifaceted approach, including selective breeding of oyster stocks, expansion of hatchery capacity, continued monitoring of coastal water chemistry, and improved understanding of biological responses will all be essential to the survival of the US west coast shellfish industry

Creative destruction in science

Drawing on the concept of a gale of creative destruction in a capitalistic economy, we argue that initiatives to assess the robustness of findings in the organizational literature should aim to simultaneously test competing ideas operating in the same theoretical space. In other words, replication efforts should seek not just to support or question the original findings, but also to replace them with revised, stronger theories with greater explanatory power. Achieving this will typically require adding new measures, conditions, and subject populations to research designs, in order to carry out conceptual tests of multiple theories in addition to directly replicating the original findings. To illustrate the value of the creative destruction approach for theory pruning in organizational scholarship, we describe recent replication initiatives re-examining culture and work morality, working parents\u2019 reasoning about day care options, and gender discrimination in hiring decisions. Significance statement It is becoming increasingly clear that many, if not most, published research findings across scientific fields are not readily replicable when the same method is repeated. Although extremely valuable, failed replications risk leaving a theoretical void\u2014 reducing confidence the original theoretical prediction is true, but not replacing it with positive evidence in favor of an alternative theory. We introduce the creative destruction approach to replication, which combines theory pruning methods from the field of management with emerging best practices from the open science movement, with the aim of making replications as generative as possible. In effect, we advocate for a Replication 2.0 movement in which the goal shifts from checking on the reliability of past findings to actively engaging in competitive theory testing and theory building. Scientific transparency statement The materials, code, and data for this article are posted publicly on the Open Science Framework, with links provided in the article