276 research outputs found

    Competing Explanations of U.S. Defense Industry Consolidation in the 1990s and Their Policy Implications

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    Was the consolidation of defense industry in the 1990s driven by U.S. Department of Defense (DOD) directives, or was it driven instead by the same forces that drove consolidation in many other sectors of the U.S. economy in the 1990s? To better understand the roles of DOD policy and economy-wide forces in shaping the U.S. defense industry, we test for structural breaks in defense industry and spending data and compare our findings to those relating to other sectors and the general economy. We identify structural breaks in the defense-related data in the early 1980s and throughout the 1990s, roughly consistent with changes in the U.S. economy, including broader merger trends. Overall, our results are more consistent with the view that economy-wide factors drove defense industry consolidation, largely independent of the DOD policy changes that occurred early in the 1990s.

    Examining Spillover Effects from Teach For America Corps Members in Miami-Dade County Public Schools

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    Despite a large body of evidence documenting the effectiveness of Teach For America (TFA) corps members at raising the math test scores of their students, little is known about the program's impact at the school level. TFA's recent placement strategy in the Miami-Dade County Public Schools (M-DCPS), where large numbers of TFA corps members are placed as clusters into a targeted set of disadvantaged schools, provides an opportunity to evaluate the impact of the TFA program on broader school performance. This study examines whether the influx of TFA corps members led to a spillover effect on other teachers' performance. We find that many of the schools chosen to participate in the cluster strategy experienced large subsequent gains in math achievement. These gains were driven in part by the composition effect of having larger numbers of effective TFA corps members. However, we do not find any evidence that the clustering strategy led to any spillover effect on school-wide performance. In other words, our estimates suggest that extra student gains for TFA corps members under the clustering strategy would be equivalent to the gains that would result from an alternate placement strategy where corps members were evenly distributed across schools

    Early SHH-Dependent Telencephalic Patterning Disruptions in Tourette Syndrome

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    Ventral telencephalic development gives rise to the basal ganglia, a subpallial brain region responsible for motor function and coordination. This brain region is implicated in many movement disorders, including Tourette Syndrome (TS). TS is a heterogenous neurodevelopmental disorder and its etiopathophysiology is unknown. To date, TS has been investigated in animal models and postnatal human subjects, but early development of this disorder has not been studied. Previous work in adult TS post mortem basal ganglia tissue has shown a reduction in striatal interneurons, which serve to largely regulate striatal output. However, possible mechanisms for this neuronal loss and whether or not these findings originate in early development are poorly understood. This study examines TS etiology by modeling basal ganglia development in tridimensional human induced pluripotent stem cell-derived neural organoids. Basal ganglia organoids were generated from and compared across healthy unaffected control individuals and adult unremitting TS patients. We found early telencephalic patterning disruptions in TS-derived basal ganglia organoids, showing a preference for dorsal-posterior specification instead of the expected ventral-anterior commitment seen in healthy control-derived organoids. The aberrant fate shift in the TS-derived basal ganglia organoids was seen at both RNA and protein levels, confirmed across three separate assays, with consistency across three distinct time points. Transcriptome analyses in the organoids further identified categories of neuronal deficits that show overlap with a manually curated list of differentially expressed genes uncovered by transcriptome analyses at the post mortem level, reiterating the relevance of the bioassay utilized in this study. This work also investigated a potential mechanism for the early developmental phenotypes observed in the TS organoids. We found significant alterations in sonic hedgehog (SHH) signaling components at both RNA and protein levels that are essential for distinguishing dorsal-ventral patterning in the human brain. Additionally, transcriptome analyses reveal a potential role for cilia, the cellular protrusions that facilitate SHH signal transduction. We found disruptions in genes that are required for cilia formation and function in the TS basal ganglia organoids that were absent from the healthy controls. This study leads an early developmental examination of TS in humans and offers a bioassay applicable to modeling basal ganglia-related disorders. These results reveal new biomarkers of interest in TS etiology and describe a new implication for SHH signaling. These results indicate that TS patients may exhibit altered telencephalic development, which yields deficits in neurons that ultimately populate the basal ganglia and regulate optimal circuitry function

    In our own hands: SWAA-Ghana champions the female condom

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    This issue of Quality/Calidad/Qualité describes the vital role played by the Ghana branch of the Society for Women and AIDS in Africa (SWAA) in introducing the female condom, the only female-controlled method for protection from HIV. By addressing issues of gender inequity and communication within relationships, SWAA used the female condom to empower women to regain control of their bodies. Also in this issue are profiles of three other approaches to programming for the female condom from Brazil, South Africa, and Zimbabwe

    Science at the Heart of Psychotherapy: A Review of Three Evidence-Based Treatments

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    Changes in the U.S. healthcare system over the past fewdecades have led to a transformation of the mental healthfield. The demand for accountability and the need for effective,cost-efficient treatments have spurred the movementtoward evidence-based practices. Today, a number of empiricallybased psychotherapies exist that have proven efficaciousin the treatment of a wide range of physical and psychologicaldisorders. Despite the strong evidence base for these treatments,their dissemination and implementation have beenslow. The intention of the present article is to summarize themajor characteristics of three types of psychotherapy (cognitivebehavioral therapy, acceptance and commitment therapy,and dialectical behavior therapy) that have received muchempirical support and have demonstrated applicability to awide range of both mental and medical problems. For eachtreatment, some background information is provided, alongwith the theoretical underpinnings of the treatment, a summaryof the current state of the evidence, and limitations andcriticisms in the literature

    Pseudomonas kirkiae sp. nov., a novel species isolated from oak in the United Kingdom, and phylogenetic considerations of the genera Pseudomonas, Azotobacter and Azomonas

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    As the current episode of Acute Oak Decline (AOD) continues to affect native British oak in the United Kingdom, ongoing isola-tions from symptomatic and healthy oak have yielded a large Pseudomonas species population. These strains could be divided into taxa representing three potential novel species. Recently, two of these taxa were described as novel Pseudomonas species in the Pseudomonas fluorescens lineage. Here, we demonstrate using a polyphasic approach that the third taxon represents another novel Pseudomonas species. The 16S rRNA gene sequencing assigned the strains to the Pseudomonas aeruginosa lineage, while multilocus sequence analysis (based on partial gyrB, rpoB and rpoD sequences) placed the 13 strains in a single cluster on the border of the Pseudomonas stutzeri group. Whole genome intra-species comparisons (based on average nucleotide identity and in silico DNA–DNA hybridization) confirmed that the strains belong to a single taxon, while the inter-species comparisons with closest phylogenetic relatives yielded similarity values below the accepted species threshold. Therefore, we propose these strains as a novel species, namely Pseudomonas kirkiae sp. nov., with the type strain FRB 229T (P4CT=LMG 31089T=NCPPB 4674T). The phylogenetic analyses performed in this study highlighted the difficulties in assigning novel species to the genus Pseudomonas due to its polyphyletic nature and close relationship to the genus Azotobacter. We further propose that a thorough taxonomic re-evaluation of the genus Pseudomonas is essential and should be performed in the near future

    Pseudomonas daroniae sp. nov. and Pseudomonas dryadis sp. nov., isolated from pedunculate oak affected by acute oak decline in the UK

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    Twenty-two cream-coloured bacterial strains were isolated from oak trees affected by acute oak decline (AOD) in Southern England. Isolates were Gram-negative, motile, slightly curved rods, aerobic, non-spore-forming, catalase positive and oxidase positive. 16S rRNA gene sequence analysis placed the strains in two separate phylogenetic clusters in the Pseudomonas straminea group, with Pseudomonas flavescens as the closest phylogenetic relative. Multilocus sequence analyses of the gyrB, rpoD and rpoB genes supported the delineation of the strains into two separate taxa, which could be differentiated phenotypically and chemotaxonomically from each other, and their closest relatives. Average nucleotide identity and in silico DNA-DNA hybridization values revealed percentages of genome similarity below the species threshold (95 and 70 %, respectively) between the two taxa and the closest relatives, confirming their novel species status. Therefore, on the basis of this polyphasic approach we propose two novel Pseudomonas species, Pseudomonasdaroniae sp. nov. (type strain FRB 228T=LMG 31087T=NCPPB 4672T) and Pseudomonasdryadis sp. nov. (type strain FRB 230T=LMG 31087T=NCPPB 4673T)

    TREM2 is required for microglial instruction of astrocytic synaptic engulfment in neurodevelopment

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    Variants in the microglial receptor TREM2 confer risk for multiple neurodegenerative diseases. However, it remains unknown how this receptor functions on microglia to modulate these diverse neuropathologies. To understand the role of TREM2 on microglia more generally, we investigated changes in microglial function in Trem2−/− mice. We found that loss of TREM2 impairs normal neurodevelopment, resulting in reduced synapse number across the cortex and hippocampus in 1-month-old mice. This reduction in synapse number was not due directly to alterations in interactions between microglia and synapses. Rather, TREM2 was required for microglia to limit synaptic engulfment by astrocytes during development. While these changes were largely normalized later in adulthood, high fat diet administration was sufficient to reinitiate TREM2-dependent modulation of synapse loss. Together, this identifies a novel role for microglia in instructing synaptic pruning by astrocytes to broadly regulate appropriate synaptic refinement, and suggests novel candidate mechanisms for how TREM2 and microglia could influence synaptic loss in brain injury and disease

    A Survey of NAPNAP Members’ Clinical and Professional Research Priorities

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    Introduction The purpose of this methodological article is to describe the development, implementation, and analysis of the survey used to determine NAPNAP members\u27 ranking of research priorities, to describe the top priorities ranked by participants, and to determine if priorities differed by area of practice (primary, acute, or specialty care) or participant age. Method A cross-sectional descriptive design with an online survey was used. Completed by 324 NAPNAP members, the survey consisted of a demographic section and 90 statements in two domains: Clinical Priorities and Professional Role Priorities. Results Survey respondents strongly supported the top priorities with an average overall mean score of 4.0 or above on a 5-point Likert scale. Only three of the top 10 clinical and professional priorities differed by area of practice. No clinical priorities and only three professional priorities differed by age. Discussion The survey results were used to develop the NAPNAP Research Agenda. Both the survey results and the agenda can provide guidance for the NAPNAP Board, committees and interests groups as they develop initiatives and programs
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