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Social capital is widely cited as benefiting children's school performance, but close inspection of existing research yields inconsistent findings. Focusing on intergenerational closure among parents of children in the same school, this article draws from a field experiment to test the effects of social capital on children's achievement in reading and mathematics. When children were in first grade, their schools were randomly assigned to an after-school family-based intervention that boosts social capital. A total of 52 schools in Phoenix, Arizona, and San Antonio, Texas, containing over 3,000 first graders, participated in the study, with half the schools in each city assigned to the treatment group and half serving as no-treatment controls. Two years later, no differences in third-grade achievement were evident between children who had been in treatment schools versus control schools. By contrast, nonexperimental analyses of survey-based measures of social capital suggest positive effects on achievement, indicating that naïve estimates based on survey measures may be upwardly biased by unobserved conditions that lead to both stronger ties among parents and higher test scores. This article adds to a growing literature that raises doubts about the effects of this type of social capital for achievement outcomes among young children.

All children have the right to an education and a voice, to be heard and to influence aspects of their lives and their education. Children and young people in foster care face unique and often challenging experiences that can make them vulnerable to having these basic rights eroded. This paper presents the findings from an in-depth study exploring the educational experiences and self-determined educational successes of young people who spent time in foster care in New Zealand. Findings from semi-structured interviews with seven young people reflected broad and holistic experiences of educational success. Relationships with teachers, foster caregivers and friends were key supports to success, along with having a voice, influence over decisions and having an advocate. Young people demonstrated marked resilience throughout the challenges they faced, which was both supportive to success, and a success in itself. Given the unique life experiences of children and young people in foster care, there is an imperative to create space for their voices to determine and define what educational success means. They need their rights to share these perspectives to enhance their own educational experiences, and to influence both the policy and practice agendas around foster care and education.

Entamoeba histolytica is the cause of amoebiasis. The trophozoite (amoeba) form of this parasite is capable of invading the intestine and can disseminate through the bloodstream to other organs. The mechanisms that allow amoebae to evade complement deposition during dissemination have not been well characterized. We previously discovered a novel complement-evasion mechanism employed by E. histolytica. E. histolytica ingests small bites of living human cells in a process termed trogocytosis. We demonstrated that amoebae were protected from lysis by human serum following trogocytosis of human cells and that amoebae acquired and displayed human membrane proteins from the cells they ingested. Here, we aimed to define how amoebae are protected from complement lysis after performing trogocytosis. We found that amoebae were protected from complement lysis after ingestion of both human Jurkat T cells and red blood cells and that the level of protection correlated with the amount of material ingested. Trogocytosis of human cells led to a reduction in deposition of C3b on the surface of amoebae. We asked whether display of human complement regulators is involved in amoebic protection, and found that CD59 was displayed by amoebae after trogocytosis. Deletion of a single complement-regulatory protein, CD59 or CD46, from Jurkat cells was not sufficient to alter amoebic protection from lysis, suggesting that multiple, redundant complement regulators mediate amoebic protection. However, exogeneous expression of CD46 or CD55 in amoebae was sufficient to confer protection from lysis. These studies shed light on a novel strategy for immune evasion by a pathogen. IMPORTANCE Entamoeba histolytica is the cause of amoebiasis, a diarrheal disease of global importance. While infection is often asymptomatic, the trophozoite (amoeba) form of this parasite is capable of invading and ulcerating the intestine and can disseminate through the bloodstream to other organs. Understanding how E. histolytica evades the complement system during dissemination is of great interest. Here, we demonstrate for the first time that amoebae that have performed trogocytosis (nibbling of human cells) resist deposition of the complement protein C3b. Amoebae that have performed trogocytosis display the complement-regulatory protein CD59. Overall, our studies suggest that acquisition and display of multiple, redundant complement regulators is involved in amoebic protection from complement lysis. These findings shed light on a novel strategy for immune evasion by a pathogen. Since other parasites use trogocytosis for cell killing, our findings may apply to the pathogenesis of other infections.

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While Entamoeba histolytica remains a globally important pathogen, it is dramatically understudied. The tractability of E. histolytica has historically been limited, which is largely due to challenging features of its genome. To enable forward genetics, we constructed and validated the first genome-wide E. histolytica RNAi knockdown mutant library. This library allows for Illumina deep sequencing analysis for quantitative identification of mutants that are enriched or depleted after selection. We developed a novel analysis pipeline to precisely define and quantify gene fragments. We used the library to perform the first RNAi screen in E. histolytica and identified slow growth (SG) mutants. Among genes targeted in SG mutants, many had annotated functions consistent with roles in cellular growth or metabolic pathways. Some targeted genes were annotated as hypothetical or lacked annotated domains, supporting the power of forward genetics in uncovering functional information that cannot be gleaned from databases. While the localization of neither of the proteins targeted in SG1 nor SG2 mutants could be predicted by sequence analysis, we showed experimentally that SG1 localized to the cytoplasm and cell surface, while SG2 localized to the cytoplasm. Overexpression of SG1 led to increased growth, while expression of a truncation mutant did not lead to increased growth, and thus aided in defining functional domains in this protein. Finally, in addition to establishing forward genetics, we uncovered new details of the unusual E. histolytica RNAi pathway. These studies dramatically improve the tractability of E. histolytica and open up the possibility of applying genetics to improve understanding of this important pathogen.

Trogocytosis is part of an emerging, exciting theme of cell-cell interactions both within and between species, and it is relevant to host-pathogen interactions in many different contexts. Trogocytosis is a process in which one cell physically extracts and ingests "bites" of cellular material from another cell. It was first described in eukaryotic microbes, where it was uncovered as a mechanism by which amoebae kill cells. Trogocytosis is potentially a fundamental form of eukaryotic cell-cell interaction, since it also occurs in multicellular organisms, where it has functions in the immune system, in the central nervous system, and during development. There are numerous scenarios in which trogocytosis occurs and an ever-evolving list of functions associated with this process. Many aspects of trogocytosis are relevant to microbial pathogenesis. It was recently discovered that immune cells perform trogocytosis to kill Trichomonas vaginalis parasites. Additionally, through trogocytosis, Entamoeba histolytica acquires and displays human cell membrane proteins, enabling immune evasion. Intracellular bacteria seem to exploit host cell trogocytosis, since they can use it to spread from cell to cell. Thus, a picture is emerging in which trogocytosis plays critical roles in normal physiology, infection, and disease.

We previously showed that Entamoeba histolytica kills human cells through a mechanism that we termed trogocytosis ("trogo-" means "nibble"), due to its resemblance to trogocytosis in other organisms. In microbial eukaryotes like E. histolytica, trogocytosis is used to kill host cells. In multicellular eukaryotes, trogocytosis is used for cell killing and cell-cell communication in a variety of contexts. Thus, nibbling is an emerging theme in cell-cell interactions both within and between species. When trogocytosis occurs between mammalian immune cells, cell membrane proteins from the nibbled cell are acquired and displayed by the recipient cell. In this study, we tested the hypothesis that through trogocytosis, amoebae acquire and display human cell membrane proteins. We demonstrate that E. histolytica acquires and displays human cell membrane proteins through trogocytosis and that this leads to protection from lysis by human serum. Protection from human serum occurs only after amoebae have undergone trogocytosis of live cells but not phagocytosis of dead cells. Likewise, mutant amoebae defective in phagocytosis, but unaltered in their capacity to perform trogocytosis, are protected from human serum. Our studies are the first to reveal that amoebae can display human cell membrane proteins and suggest that the acquisition and display of membrane proteins is a general feature of trogocytosis. These studies have major implications for interactions between E. histolytica and the immune system and also reveal a novel strategy for immune evasion by a pathogen. Since other microbial eukaryotes use trogocytosis for cell killing, our findings may apply to the pathogenesis of other infections.IMPORTANCE Entamoeba histolytica causes amoebiasis, a potentially fatal diarrheal disease. Abscesses in organs such as the liver can occur when amoebae are able to breach the intestinal wall and travel through the bloodstream to other areas of the body. Therefore, understanding how E. histolytica evades immune detection is of great interest. Here, we demonstrate for the first time that E. histolytica acquires and displays human cell membrane proteins by taking "bites" of human cell material in a process named trogocytosis ("trogo-" means "nibble"), and that this allows amoebae to survive in human serum. Display of acquired proteins through trogocytosis has been previously characterized only in mammalian immune cells. Our study suggests that this is a more general feature of trogocytosis not restricted to immune cells and broadens our knowledge of eukaryotic biology. These findings also reveal a novel strategy for immune evasion by a pathogen and may apply to the pathogenesis of other infections.

High carbon isotope values (δ13CCH4 > −40‰) have widely been used as evidence that methane in alkaline rock-hosted fluids was formed abiotically, particularly in serpentinizing systems. However, isotope fractionation during microbial methanogenesis is relatively understudied at high pH. We isolated a hydrogenotrophic Methanobacterium sp. from hyperalkaline subsurface fluids in the Samail ophiolite to assess how carbon and hydrogen isotope values of CH4 varied depending upon pH and carbonate mineral source (NaHCO3 or CaCO3). The hydrogen isotope fractionation αH20/CH4 (1.46–1.66) did not vary across pH. In contrast, the expressed carbon isotope fractionation, αCO2/CH4, ranged from 1.028 to 1.089. Carbon isotope fractionation increased with pH, reaching a maximum 13C depletion of −85‰. However, the 13C depletion significantly diminished at pH ≥ 9 for CaCO3-amended experiments, generating δ13CCH4 as high as −28‰. To evaluate the large variability in δ13CCH4, we developed a steady-state model to assess how the rates of carbonate dissolution, cellular uptake of CO2 and irreversible CH4 production can affect the net isotope fractionation during methanogenesis. Methanobacterium sp. can produce highly depleted δ13CCH4 in simulated alkaline serpentinizing fluids when dissolved inorganic carbon levels are high and methanogenesis rates are slow. However, small carbon isotope fractionation occurs when rates of carbonate dissolution are slower than cellular uptake, leading to relatively high δ13CCH4 values (>∼−35‰) that are traditionally interpreted to be purely “abiotic”. Thus, microbial CH4 can be produced in carbon-limited mafic and ultramafic rock-hosted environments on Earth and potentially other planetary bodies, but it may be difficult to isotopically identify biogenic methane when mineral carbonates are the dominant carbon source.

Purpose: Valued living (acting in accordance with personal values) is associated with better outcomes after acquired brain injury (ABI), but its measurement using the Valued Living Questionnaire (VLQ) may not be valid due to comprehension errors relating to structure and content. We aimed to modify the VLQ to improve its accessibility and evaluate construct validity and reliability in an ABI cohort. Materials and methods: Adaptations made in the VLQ – Comprehension Support version (VLQ-CS) used established communication support methods and addressed common comprehension errors. 103 community-dwelling participants (34% female; mean age 52.17, range 19–79) with ABI (66% stroke, 16% TBI, 18% other) completed the VLQ-CS, and measures of convergent (valued living, mood, wellbeing, psychological inflexibility) and divergent validity (subjective memory). Test-retest reliability was evaluated with repeated administrations 6–8 weeks apart for a subset of participants (n = 44), using Intraclass Correlation Coefficients (ICCs). Results: Convergent validity was supported; VLQ-CS scores were positively correlated with measures of valued living (r=.60–.65) and wellbeing (r=.64–.67), and negatively correlated with depression (r=-0.56–.58), anxiety (r=-0.35–.38) and psychological inflexibility (r=-0.37–.41). Divergent validity was marginal (r=-0.29). Test-retest reliability was good for the VLQ-CS Composite score (ICC=.80). Conclusions: The VLQ-CS shows promise as a valid, reliable measure of valued living post-ABI. Future research should extend to neurotypical and other clinical populations. IMPLICATIONS FOR REHABILITATION: Valued living or values-based action is associated with better functional and psychosocial outcomes after acquired brain injury (ABI) and is therefore an important target for intervention. Measurement of valued living needs to be clear, easily understood, and relevant for people with cognitive and communication impairments associated with ABI and other conditions. The Valued Living Questionnaire – Comprehension Support version (VLQ-CS) was developed to optimise accessibility and reduce comprehension errors. The VLQ-CS is valid, reliable and fit-for-purpose as a measure of valued living for people with ABI. [ABSTRACT FROM AUTHOR]

The article focuses on a 10-year-old female with a month-long history of intermittent fever, fatigue, joint pain, and rash, whose condition worsened despite outpatient evaluation, prompting a return to the pediatric emergency department. Topics include the patient's medical history including epilepsy and recent COVID-19 vaccination, laboratory findings such as anemia and a positive respiratory pathogen panel for Coronavirus OC43.

The Samail ophiolite in Oman is undergoing modern hydration and carbonation of peridotite and may host a deep subsurface biosphere. Previous investigations of hyperalkaline fluids in Oman have focused on fluids released at surface seeps, which quickly lose their reducing character and precipitate carbonates upon contact with the O2/CO2-rich atmosphere. In this work, geochemical analysis of rocks and fluids from the subsurface provides new insights into the operative reactions in serpentinizing aquifers. Serpentinite rock and hyperalkaline fluids (pH > 10), which exhibit millimolar concentrations of Ca2+, H2 and CH4, as well as variable sulfate and nitrate, were accessed from wells situated in mantle peridotite near Ibra and studied to investigate their aqueous geochemistry, gas concentrations, isotopic signatures, mineralogy, Fe speciation and microbial community composition.The bulk mineralogy of drill cuttings is dominated by olivine, pyroxene, brucite, serpentine and magnetite. At depth, Fe-bearing brucite is commonly intermixed with serpentine, whereas near the surface, olivine and brucite are lost and increased magnetite and serpentine is detected. Micro-Raman spectroscopy reveals at least two distinct generations of serpentine present in drill cuttings recovered from several depths from two wells. Fe K-edge X-ray absorption near-edge spectroscopy (XANES) analysis of the lizardite shows a strong tetrahedral Fe coordination, suggesting a mixture of both Fe(II) and Fe(III) in the serpentine. Magnetite veins are also closely associated with this second generation serpentine, and 2-10 μm magnetite grains overprint all minerals in the drill cuttings. Thus we propose that the dissolved H2 that accumulates in the subsurface hyperalkaline fluids was evolved through low temperature oxidation and hydration of relict olivine, as well as destabilization of pre-existing brucite present in the partially serpentinized dunites and harzburgites. In particular, we hypothesize that Fe-bearing brucite is currently reacting with dissolved silica in the aquifer fluids to generate late-stage magnetite, additional serpentine and dissolved H2. Dissolved CH4 in the fluids exhibits the most isotopically heavy carbon in CH4 reported in the literature thus far. The CH4 may have formed through abiotic reduction of dissolved CO2 or through biogenic pathways under extreme carbon limitation. The methane isotopic composition may have also been modified by significant methane oxidation. 16S rRNA sequencing of DNA recovered from filtered hyperalkaline well fluids reveals an abundance of Meiothermus, Thermodesulfovibrionaceae (sulfate-reducers) and Clostridia (fermenters). The fluids also contain candidate phyla OP1 and OD1, as well as Methanobacterium (methanogen) and Methylococcus sp. (methanotroph). The composition of these microbial communities suggests that low-temperature hydrogen and methane generation, coupled with the presence of electron acceptors such as nitrate and sulfate, sustains subsurface microbial life within the Oman ophiolite.

INTRODUCTION 1211 I. THE DANGER OF "GENERAL" ELECTIONS 1 1216 A. The Importance of a Nonpartisan Military 1216 B. Flag Officer Endorsements Impede Civilian 1219 Control and Military Effectiveness 1 [...], Retired generals and admirals of the U.S. military appear to be endorsing partisan political candidates in greater numbers, with more visibility. This Note argues that the practice represents a clear danger to civilian control over the military and weakens military effectiveness. It explains that while retirees remain subject to military jurisdiction, the existing array of statutory and regulatory restrictions on political activity cannot adequately address the problem. Neither can professional norms be expected to shore themselves up to solve it. This Note describes how political restrictions on servicemembers have evolved over time in response to novel challenges to civilian control. It illustrates that retired officers--who receive lifetime pensions and remain subject to recall--have always been a part of the civilian-control conversation. It also analogizes to judicial ethics, Hatch Act prohibitions, and postemployment business ethics restrictions on military retirees, finding several compelling state interests that could justify narrowly tailored restraints on retiree speech. This Note ultimately offers an assortment of potential legal responses to the endorsement problem. These include modest changes that others have proposed, such as additional disclaimers, restrictions on the use of ranks and titles, and rules that would formally ostracize endorsers from events and partnerships with the active military. The Note also suggests a more radical last-ditch proposal: officers seeking promotion to general or admiral would have to agree, as a term of their employment contract at the highest ranks, to refrain from endorsing partisan candidates for eight years after retirement. Certainly, retired flag officer endorsements represent only one symptom of a larger civil-military divide in the United States. But this symptom deserves further study, and not just because of its harmful effects. It serves as a reminder that while civilian control may be a fundamental, constitutionally derived principle, it relies on measures beyond the Constitution to manifest and protect it.