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Introduction: The career choices of medical graduates vary widely between medical schools in the UK and elsewhere and are generally not well matched with societal needs. Research has found that experiences in medical school including formal, informal and hidden curricula are important influences. We conducted a realist evaluation of how and why these various social conditions in medical school influence career thinking. Methods: We interviewed junior doctors at the point of applying for speciality training. We selected purposively for a range of career choices. Participants were asked to describe points during their medical training when they had considered career options and how their thinking had been influenced by their context. Interview transcripts were coded for context-mechanism-outcome (CMO) configurations to test initial theories of how career decisions are made. Results: A total of 26 junior doctors from 12 UK medical schools participated. We found 14 recurring CMO configurations in the data which explained influences on career choice occurring during medical school. Discussion: Our initial theories about career decision-making were refined as follows: It involves a process of testing for fit of potential careers. This process is asymmetric with multiple experiences needed before deciding a career fits ('easing in') but sometimes only a single negative experience needed for a choice to be ruled out. Developing a preference for a speciality aligns with Person-Environment-Fit decision theories. Ruling out a potential career can however be a less thought-through process than rationality-based decision theories would suggest. Testing for fit is facilitated by longer and more authentic undergraduate placements, allocation of and successful completion of tasks, being treated as part of the team and enthusiastic role models. Informal career guidance is more influential than formal. We suggest some implications for medical school programmes. [ABSTRACT FROM AUTHOR]

Let G$G$ be a simple algebraic group over an algebraically closed field k$\mathbb {k}$ of characteristic 2. We consider analogues of the Jacobson–Morozov theorem in this setting. More precisely, we classify those nilpotent elements with a simple 3‐dimensional Lie overalgebra in g:=Lie(G)$\mathfrak {g}:=\operatorname{Lie}(G)$ and also those with overalgebras isomorphic to the algebras Lie(SL2)$\operatorname{Lie}(\mathrm{SL}_2)$ and Lie(PGL2)$\operatorname{Lie}(\mathrm{PGL}_2)$. This leads us to calculate the dimension of the Lie automiser ng(k·e)/cg(e)$\mathfrak {n}_\mathfrak {g}(\mathbb {k}\cdot e)/\mathfrak {c}_\mathfrak {g}(e)$ for all nilpotent orbits; in even characteristic this quantity is very sensitive to isogeny. [ABSTRACT FROM AUTHOR]

This article examines the crucial roles Black people played in the development of Western Carolina University (WCU) in the mountains of Southern Appalachia, and the university's failure to fully acknowledge the contributions those people have made. After introducing some relevant oral history projects, we focus on the history of the WCU land. We first describe the Indigenous dispossession by which the white Rogers family acquired the land in Cullowhee, North Carolina. We then turn to Harriet, an African American woman enslaved by David Rogers, Sr., considering how her and her children's labor shaped the property he eventually transferred to the university. The article subsequently traces the lives of several of Harriet's descendants, and their contributions to the university's growth. We also consider how WCU's expansion relied on the appropriation of land upon which a crucial Black AME Zion Church sat. We contend that, as with the prior Cherokee dispossession, WCU has yet to fully acknowledge the contributions of Black people to its development. The contributions of local Black community members should be recognized especially in light of the university's reliance on its mountain location as the basis of its "brand identity." [ABSTRACT FROM AUTHOR]

Although the last several decades have seen a dramatic reduction in emissions from vehicular exhaust, nonexhaust emissions (e.g., brake and tire wear) represent an increasingly significant class of traffic-related particulate pollution. Aerosol particles emitted from the wear of automotive brake pads contribute roughly half of the particle mass attributed to nonexhaust sources, while their relative contribution to urban air pollution overall will almost certainly grow coinciding with vehicle fleet electrification and the transition to alternative fuels. To better understand the implications of this growing prominence, a more thorough understanding of the physicochemical properties of brake wear particles (BWPs) is needed. Here, we investigate the electrical properties of BWPs as emitted from ceramic and semi-metallic brake pads. We show that up to 80% of BWPs emitted are electrically charged and that this fraction is strongly dependent on the specific brake pad material used. A dependence of the number of charges per particle on charge polarity and particle size is also demonstrated. We find that brake wear produces both positive and negative charged particles that can hold in excess of 30 elementary charges and show evidence that more negative charges are produced than positive. Our results will provide insights into the currently limited understanding of BWPs and their charging mechanisms, which potentially have significant implications on their atmospheric lifetimes and thus their relevance to climate and air quality. In addition, our study will inform future efforts to remove BWP emissions before entering the atmosphere by taking advantage of their electric charge. [ABSTRACT FROM AUTHOR]

The article asks why the family of African American farmer Percy Claud and numerous other African Americans in and around Southampton County, Virginia remembered the death of Nat Turner, an African American slave who led an uprising against slave owners in August 1831, as a lynching by an outraged white mob rather than a legally appointed execution on behalf of the state. The meaning of Turner's death and his fellow rebels for opponents of slavery is also discussed.

Cancer is a leading cause of mortality worldwide. B-cells are a keystone of the adaptive immune response and are essential for the presentation of tumor-associated antigens to various types of T-cells. Approximately 1.5% of global cancer cases, including breast and gastric carcinomas and both Hodgkin's and non-Hodgkin's lymphomas, are linked with prior Epstein–Barr Virus (EBV) infection. Such properties make EBV-infected lymphocytes ideal models for understanding the effect of oxyhydrogen gas on dysfunctional cell cycling. The aim of this study is to assess the effects of the direct infusion of oxyhydrogen gas on the replicative capacity of EBV-immortalised B-lymphocytes. Oxyhydrogen gas was directly infused into cell culture media. Cells were incubated in 95% air and 5% CO2 for up to 72 h. Cell enumeration was assessed with and without the addition of mitogenic growth stimuli, and subsequent cell-cycle analysis was performed. Cell enumeration: An initial trend of replicative inhibition of TK6 cells is noted with a single oxyhydrogen treatment at the 24 and 48 h time points. The daily addition of oxyhydrogen-infused media showed statistically relevant data at 24 and 48 h but not at 72 h. In mitogen-stimulated cells, a non-statistical trend of inhibition was observed at 24, 48 and 72 h. Analysis details a significant increase in DNA in the Sub G1 phase, indicating increased apoptosis. [ABSTRACT FROM AUTHOR]

Donor cell leukaemia (DCL) is a complication of haematopoietic stem cell transplantation where donated cells become malignant within the patient's bone marrow. As DCL predominates as acute myeloid leukaemia, we hypothesized that the cytokine storm following chemotherapy played a role in promoting and supporting leukaemogenesis. Cytokines have also been implicated in genotoxicity; thus, we explored a cell line model of the human bone marrow (BM) to secrete myeloid cytokines following drug treatment and their potential to induce micronuclei. HS-5 human stromal cells were exposed to mitoxantrone (MTX) and chlorambucil (CHL) and, for the first time, were profiled for 80 cytokines using an array. Fifty-four cytokines were detected in untreated cells, of which 24 were upregulated and 10 were downregulated by both drugs. FGF-7 was the lowest cytokine to be detected in both untreated and treated cells. Eleven cytokines not detected at baseline were detected following drug exposure. TNFα, IL6, GM-CSF, G-CSF, and TGFβ1 were selected for micronuclei induction. TK6 cells were exposed to these cytokines in isolation and in paired combinations. Only TNFα and TGFβ1 induced micronuclei at healthy concentrations, but all five cytokines induced micronuclei at storm levels, which was further increased when combined in pairs. Of particular concern was that some combinations induced micronuclei at levels above the mitomycin C positive control; however, most combinations were less than the sum of micronuclei induced following exposure to each cytokine in isolation. These data infer a possible role for cytokines through chemotherapy-induced cytokine storm, in the instigation and support of leukaemogenesis in the BM, and implicate the need to evaluate individuals for variability in cytokine secretion as a potential risk factor for complications such as DCL. [ABSTRACT FROM AUTHOR]

Let G = O p ′ ( G ¯ F) be a finite simple group of Lie type defined over a field of characteristic p , where F is a Steinberg endomorphism of the ambient simple algebraic group G ¯. Let T ¯ be an F -stable maximal torus of G ¯ and set N = N G (T ¯). A conjecture due to Vdovin asserts that if G ≇ L 3 (2) then N ∩ N x is a p -group for some x ∈ G. In this paper, we use a combination of probabilistic and computational methods to calculate the base size for the natural action of G on G / N , which allows us to prove a stronger, and suitably modified, version of Vdovin's conjecture. [ABSTRACT FROM AUTHOR]

Dedicated to the memory of Jan Saxl   Let |$G$| be a finite primitive permutation group on a set |$\Omega $| with nontrivial point stabilizer |$G_{\alpha }$|⁠. We say that |$G$| is extremely primitive if |$G_{\alpha }$| acts primitively on each of its orbits in |$\Omega \setminus \{\alpha \}$|⁠. These groups arise naturally in several different contexts, and their study can be traced back to work of Manning in the 1920s. In this paper, we determine the almost simple extremely primitive groups with socle an exceptional group of Lie type. By combining this result with earlier work of Burness, Praeger, and Seress, this completes the classification of the almost simple extremely primitive groups. Moreover, in view of results by Mann, Praeger, and Seress, our main theorem gives a complete classification of all finite extremely primitive groups, up to finitely many affine exceptions (and it is conjectured that there are no exceptions). Along the way, we also establish several new results on base sizes for primitive actions of exceptional groups, which may be of independent interest. [ABSTRACT FROM AUTHOR]

Background: From 2007 to 2017, sorafenib was the sole systemic therapy for hepatocellular carcinoma (HCC), but nine new therapies were approved from 2017 to 2022. No studies have yet examined population‐level treatment patterns for HCC since these approvals. Methods: For this retrospective cohort, Surveillance, Epidemiology, and End Results (SEER)–Medicare data were used to identify patients who had HCC diagnosed between 2014 and 2019 with claims through 2020. The authors examined patient characteristics, comorbidities, and receipt of local (e.g., transplantation, resection, embolization) and systemic (e.g., sorafenib, lenvatinib, atezolizumab plus bevacizumab) therapies. Cohort characteristics, treatment patterns, and overall survival (OS) were analyzed, and χ2 tests and t‐tests were used to compare treatments between the 2014–2017 and 2018–209 cohorts. Adjusted Cox models were used to compare median OS between treatment groups. Results: Among 11,766 patients (men, 69.2%; White, 76.9%; median age, 71 years), 60.5% received treatment within 1 year, which remained stable over time (2014–2017, 60.4%; 2018–2019, 61.0%; p =.84). The use of local therapy also remained stable (2014–2017, 52.1%; 2018–2019, 52.8%; p =.43), whereas the use of systemic therapy slightly decreased (2014–2017, 17.0%; 2018–2019, 15.2%; p =.01). First‐line systemic treatments shifted significantly, with sorafenib use dropping from 84.5% (2014–2017) to 41.3% (2018–2019). The median OS among patients who received no treatment, systemic therapies first, or local therapies first was 2.2, 12.0, and 23.6 months, respectively. Patients who were diagnosed in 2019 had better OS (hazard ratio [HR], 0.80; 95% confidence interval [CI], 0.74–0.86) as did those who received systemic therapy first (HR, 0.33; 95% CI, 0.18–0.61), but survival was worse for those who received local therapy first (HR, 1.41; 95% CI, 1.08–1.84) compared with those who were diagnosed in 2014. Conclusions: Local therapy patterns remained stable, but novel therapies replaced sorafenib as the preferred first‐line treatment, improving survival. Between 2017 and 2022, nine new systemic therapies were approved for hepatocellular carcinoma. Local therapies patterns remained stable, whereas systemic therapies saw a shift from sorafenib to newer therapies as first‐line treatments. This change in treatment patterns was associated with better overall survival for patients who were diagnosed in 2019 compared with those who were diagnosed in 2014. [ABSTRACT FROM AUTHOR]

Repair of DNA double-strand breaks by homologous recombination (HR) requires a carefully orchestrated sequence of events involving many proteins. One type of HR, synthesis-dependent strand annealing (SDSA), proceeds via the formation of a displacement loop (D-loop) when RAD51-coated single-stranded DNA invades a homologous template. The 3′ end of the single-stranded DNA is extended by DNA synthesis. In SDSA, the D-loop is then disassembled prior to strand annealing. While many helicases can unwind D-loops in vitro, how their action is choreographed in vivo remains to be determined. To clarify the roles of various DNA helicases during SDSA, we used a double-strand gap repair assay to study the outcomes of homologous recombination repair in Drosophila melanogaster lacking the BLM, HELQ, and FANCM helicases. We found that the absence of any of these three helicases impairs gap repair. In addition, flies lacking both BLM and HELQ or HELQ and FANCM had more severe SDSA defects than the corresponding single mutants. In the absence of BLM, a large percentage of repair events were accompanied by flanking deletions. Strikingly, these deletions were mostly abolished in the blm helq and blm fancm double mutants. Our results suggest that the BLM, HELQ, and FANCM helicases play distinct roles during SDSA, with HELQ and FANCM acting early to promote the formation of recombination intermediates that are then processed by BLM to prevent repair by deletion-prone mechanisms. [ABSTRACT FROM AUTHOR]

Herpes simplex esophagitis (HSE) represents a rare entity in immunocompetent patients and has infrequently been described in association with eosinophilic esophagitis (EoE). Causality in this rare association remains a debated topic. We present a case of HSE occurring in an immunocompetent adult with EoE and review the literature in support of EoE induced mucosal disruption predisposing to increased risk of HSE. [ABSTRACT FROM AUTHOR]

Research within civil engineering is focusing on newer ideas and philosophies such as sustainability and resiliency (S&R). This is evident in the development of frameworks for assessing the sustainability or the resiliency of civil infrastructures. Several frameworks have been developed by researchers to quantify the S&R of civil infrastructures. It is evident that the S&R are not mutually exclusive, and it is important to assess these aspects at the same time and that frameworks are able to accommodate simultaneous assessments. While there are other frameworks that follow a unified approach to S&R assessments, they do not account for the risk of the hazard as part of the framework. In the proposed framework, an attempt was made to include the risk of the hazard as part of the assessment to gain a realistic perspective of the hazard impact. This paper presents explicit steps to use the framework, along with an example of using the framework in assessing an earthen dam subjected to two types of hazards, earthquakes and floods. The novel aspects of this framework revolve around the simplicity and flexibility of the framework. Major input parameters are user-defined, which allows for a wide range of variables to be considered when determining the overall quality of the infrastructure. [ABSTRACT FROM AUTHOR]

Dusty, neutral outflows and inflows are a common feature of nearby star-forming galaxies. We characterize these flows in eight galaxies – mostly active galactic nuclei (AGN) – selected for their widespread Na  i D signatures from the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7). This survey employs deep, wide field-of-view (FOV) integral field spectroscopy at moderate spectral resolution (R = 7000 at Na  i D). We significantly expand the sample of sightlines in external galaxies in which the spatially resolved relationship has been studied between cool, neutral gas properties – N (Na  i), W eq(Na  i D) – and dust – E (B − V) from both stars and gas. Our sample shows strong, significant correlations of total W eq with E (B − V)⋆ and g − i colour within individual galaxies; correlations with E (B − V)gas are present but weaker. Regressions yield slope variations from galaxy to galaxy and intrinsic scatter ∼1 Å. The sample occupies regions in the space of N (Na  i) and |$W_\mathrm{eq}^\mathrm{abs}$| versus E (B − V)gas that are consistent with extrapolations from other studies to higher colour excess [ E (B − V)gas ∼ 1]. For perhaps the first time in external galaxies, we detect inverse P Cygni profiles in the Na  i D line, presumably due to inflowing gas. Via Doppler-shifted Na  i D absorption and emission lines, we find ubiquitous flows that differ from stellar rotation by |$\gtrsim$| 100 km s−1 or have |$|v_{\mathrm{ abs}} - v_{\mathrm{ em}}|\gtrsim 100$|  km s−1. Inflows and outflows extend towards the edge of the detected stellar disc/FOV, together subtend 10–40 per cent of the projected disc, and have similar mean N (Na  i) and W eq(Na  i D). Outflows are consistent with minor axis or jet-driven flows, while inflows tend towards the projected major axis. The inflows may result from non-axisymmetric potentials, tidal motions, or halo infall. [ABSTRACT FROM AUTHOR]

In August 1831, around sixty enslaved people fought a war against enslavers in Southampton County, Virginia. It became known as the "Nat Turner Revolt." Four months later, perhaps sixty thousand enslaved people fought their own emancipation war, commonly known as the "Baptist War," throughout much of Jamaica. These uprisings differed in size, strategy, and outcome. The Virginian episode allowed slaveholders to strengthen their grip on slavery, while the Jamaican one catalyzed Britain's capitulation to abolition. Historians have detailed the significant role kinship played in the more localized Virginian example. Comparing both emancipation wars, this paper extends analysis to the Jamaican case. It argues that kinship shaped both uprisings in remarkably similar ways, influencing radicalization and recruitment beforehand, support or opposition during war, and vulnerability to or evasion of white retaliation afterward. The similar function of kinship in such different events suggests a possible larger pattern that shaped other uprisings. [ABSTRACT FROM AUTHOR]

Timely repair of DNA double-strand breaks (DSBs) is essential to maintaining genomic integrity and preventing illnesses induced by genetic abnormalities. We previously demonstrated that the E3 ubiquitin ligase SMURF2 plays a critical tumor suppressing role via its interaction with RNF20 (ring finger protein 20) in shaping chromatin landscape and preserving genomic stability. However, the mechanism that mobilizes SMURF2 in response to DNA damage remains unclear. Using biochemical approaches and MS analysis, we show that upon the onset of the DNA-damage response, SMURF2 becomes phosphorylated at Ser384 by ataxia telangiectasia mutated (ATM) serine/threonine kinase, and this phosphorylation is required for its interaction with RNF20. We demonstrate that a SMURF2 mutant with an S384A substitution has reduced capacity to ubiquitinate RNF20 while promoting Smad3 ubiquitination unabatedly. More importantly, mouse embryonic fibroblasts expressing the SMURF2 S384A mutant show a weakened ability to sustain the DSB response compared with those expressingWT SMURF2 following etoposide treatment. These data indicate that SMURF2-mediated RNF20 ubiquitination and degradation controlled by ataxia telangiectasia mutated-induced phosphorylation at Ser384 constitutes a negative feedback loop that regulatesDSB repair. [ABSTRACT FROM AUTHOR]

DNA damage–inducible miRNAs are likely to be functional in the DNA damage response. This response can elicit damage resolution and cell survival or apoptosis. The current, albeit incomplete, picture suggests that miRNAs can affect cell fate via modulation of key response proteins, but the question is, who's in charge? [ABSTRACT FROM AUTHOR]

We report the design and optimisation of novel oligonucleotide substrates for a sensitive fluorescence assay for high-throughput screening and functional studies of the DNA repair enzyme, XPF-ERCC1, with a view to accelerating inhibitor and drug discovery. [ABSTRACT FROM AUTHOR]

In 1839, Jamaican plantation attorney Alexander Grant sued missionaries John Stainsby and Samuel Oughton for slander; they had accused Grant of 'lewd and indecent practices' with enslaved and apprenticed men. Missionaries and abolitionist supporters on one side, and Grant and the plantocracy on the other, used the scandal to challenge their opponents' suitability to shape post-emancipation society. The trials show that sex – and same-sex sexuality – was central to the contest for social authority. Several freedmen testified that Grant had coerced them into sexual interactions. Grappling with archival silences, the essay considers how the admissions affected their sense of masculinity and communal belonging. [ABSTRACT FROM AUTHOR]

Abstract Let G be a simple algebraic group over an algebraically closed field. A closed subgroup H of G is called G -completely reducible (G -cr) if, whenever H is contained in a parabolic subgroup P of G , it is contained in a Levi factor of P. In this paper we complete the classification of connected G -cr subgroups when G has exceptional type, by determining the L 0 -irreducible connected reductive subgroups for each simple classical factor L 0 of a Levi subgroup of G. As an illustration, we determine all reducible, G -cr semisimple subgroups when G has type F 4 and various properties thereof. This work complements results of Lawther, Liebeck, Seitz and Testerman, and is vital in classifying non- G -cr reductive subgroups, a project being undertaken by the authors elsewhere. [ABSTRACT FROM AUTHOR]

Research in speech perception has explored how knowledge of a language influences phonetic perception. The current study investigated whether such linguistic influences extend to the perceptual (sequential) organization of speech. Listeners heard sinewave analogs of word pairs (e.g., loose seam, which contains a single [s] frication but is perceived as two /s/ phonemes) cycle continuously, which causes the stimulus to split apart into foreground and background percepts. They had to identify the foreground percept when the stimuli were heard as nonspeech and then again when heard as speech. Of interest was how grouping changed across listening condition when [s] was heard as speech or as a hiss. Although the section of the signal that was identified as the foreground differed little across listening condition, a strong bias to perceive [s] as forming the onset of the foreground was observed in the speech condition (Experiment 1). This effect was reduced in Experiment 2 by increasing the stimulus repetition rate. Findings suggest that the sequential organization of speech arises from the interaction of auditory and linguistic processes, with the former constraining the latter. [ABSTRACT FROM AUTHOR]

Let G be a simple algebraic group of exceptional type, over an algebraically closed field of characteristic p = 0. A closed subgroup H of G is called G-completely reducible (G-cr) if whenever H is contained in a parabolic subgroup P of G, it is contained in a Levi subgroup of P. In this paper we determine the G-conjugacy classes of non-G-cr simple connected subgroups of G when p is good for G. For each such subgroup X, we determine the action of X on the adjoint module L(G) and the connected centraliser of X in G. As a consequence we classify all non-G-cr connected reductive subgroups of G, and determine their connected centralisers. We also classify the subgroups of G which are maximal among connected reductive subgroups, but not maximal among all connected subgroups. [ABSTRACT FROM AUTHOR]

The involution fixity ifix(G) of a permutation group G of degree n is the maximum number of fixed points of an involution. In this paper we study the involution fixity of primitive almost simple exceptional groups of Lie type. We show that if T is the socle of such a group, then either ifix(T)>n1/3, or ifix(T)=1 and T=2B2(q) is a Suzuki group in its natural 2-transitive action of degree n=q2+1. This bound is best possible and we present more detailed results for each family of exceptional groups, which allows us to determine the groups with ifix(T)≤n4/9. This extends recent work of Liebeck and Shalev, who established the bound ifix(T)>n1/6 for every almost simple primitive group of degree n with socle T (with a prescribed list of exceptions). Finally, by combining our results with the Lang–Weil estimates from algebraic geometry, we determine bounds on a natural analogue of involution fixity for primitive actions of exceptional algebraic groups over algebraically closed fields. [ABSTRACT FROM AUTHOR]

We determine all finite subgroups of simple algebraic groups that have irreducible centralizers - that is, centralizers whose connected component does not lie in a parabolic subgroup. [ABSTRACT FROM AUTHOR]

Carboxylic acid reductase enzymes (CARs) meet the demand in synthetic chemistry for a green and regiospecific route to aldehydes from their respective carboxylic acids. However, relatively few of these enzymes have been characterized. A sequence alignment with members of the ANL (Acyl-CoA synthetase/ NRPS adenylation domain/Luciferase) superfamily of enzymes shed light on CAR functional dynamics. Four unstudied enzymes were selected by using a phylogenetic analysis of known and hypothetical CARs, and for the first time, a thorough biochemical characterization was performed. Kinetic analysis of these enzymes with various substrates shows that they have a broad but similar substrate specificity. Electron-rich acids are favored, which suggests that the first step in the proposed reaction mechanism, attack by the carboxylate on the α-phosphate of adenosine triphosphate (ATP), is the step that determines the substrate specificity and reaction kinetics. The effects of pH and temperature provide a clear operational window for the use of these CARs, whereas an investigation of product inhibition by NADP+, adenosine monophosphate, and pyrophosphate indicates that the binding of substrates at the adenylation domain is ordered with ATP binding first. This study consolidates CARs as important and exciting enzymes in the toolbox for sustainable chemistry and provides specifications for their use as a biocatalyst. [ABSTRACT FROM AUTHOR]

We show that the categories of compact Lie groups and complex reductive groups (not necessarily connected) are homotopy equivalent topological categories. In other words, the corresponding categories enriched in the homotopy category of topological spaces are equivalent. This can also be interpreted as an equivalence of infinity categories. [ABSTRACT FROM AUTHOR]

Objectives: The risk of pregnancy is estimated to be 20 times as high among women who use oral contraception, and 90 times as high among condom users, as among women who use certain long-acting contraceptive methods. We explored the population-level implications of this variation in contraceptive efficacy.Study Design: We used the FamilyScape 3.0 microsimulation model to study the effects on the nonmarital pregnancy rate of movements along two different margins of contraceptive behavior: the extensive margin, which captures decisions about whether to initiate use of any method of contraception among noncontraceptors; and the intensive margin, which captures the choice of methods among contraceptors. The model is populated with a nationally representative sample of 50,000 women who are of childbearing age.Results: The impact on the number of nonmarital pregnancies would not be substantially different if noncontraceptors adopted long-acting methods than if they began using oral contraception. Moreover, the nonmarital pregnancy rate would be reduced by about twice as much if a subset of noncontraceptors began using condoms as if an equal number of pill users took up long-acting methods.Conclusions: The prevailing emphasis on long-acting contraception is somewhat misplaced. Policymakers and practitioners will have the largest effects on fertility outcomes if they can change the behavior of sexually active women who neglect to use birth control when they are not seeking pregnancy.Implications: Women's decisions about which methods to use are less impactful than their decisions about whether to use contraception at all. The policies that affect method choice are likely to differ from the policies that address the underlying motivations of noncontraceptors who are not seeking pregnancy. [ABSTRACT FROM AUTHOR]

The hippocampus has been shown to demonstrate a remarkable degree of plasticity in response to a variety of tasks and experiences. For example, the size of the human hippocampus has been shown to increase in response to aerobic exercise. However, it is currently unknown what underlies these changes. Here we scanned sedentary, young to middle-aged human adults before and after a six-week exercise intervention using nine different neuroimaging measures of brain structure, vasculature, and diffusion. We then tested two different hypotheses regarding the nature of the underlying changes in the tissue. Surprisingly, we found no evidence of a vascular change as has been previously reported. Rather, the pattern of changes is better explained by an increase in myelination. Finally, we show that hippocampal volume increase is temporary, returning to baseline after an additional six weeks without aerobic exercise. This is the first demonstration of a change in hippocampal volume in early to middle adulthood suggesting that hippocampal volume is modulated by aerobic exercise throughout the lifespan rather than only in the presence of age related atrophy. It is also the first demonstration of hippocampal volume change over a period of only six weeks, suggesting that gross morphometric hippocampal plasticity occurs faster than previously thought. [ABSTRACT FROM AUTHOR]

A closed subgroup of a semisimple algebraic group is called irreducible if it lies in no proper parabolic subgroup. In this paper we classify all irreducible A 1 subgroups of exceptional algebraic groups G . Consequences are given concerning the representations of such subgroups on various G -modules: for example, the conjugacy classes of irreducible A 1 subgroups are determined by their composition factors on the adjoint module of G . [ABSTRACT FROM AUTHOR]

There is increasing evidence for non-linear relationships for gene mutations, chromosomal aberrations and even tumor incidences in response to low doses of genotoxic carcinogens. To attain the biological relevance of such non-linear responses, there is a need to identify the underlying defense mechanisms that allow tolerance to low doses of genotoxicants. This communication discusses presumptive cancer prevention mechanisms that may contribute to thresholds, i.e. points of departure, for each endpoint, from initial DNA lesion to tumor formation. We discuss a sequential order of genome protection during carcinogenesis where genotoxicant scavenging, cellular efflux, DNA repair, elimination of damaged cells by apoptosis, autophagy, silencing by DNA damage-triggered replicative senescence, and finally, elimination of transformed (premalignant) cells by the immune system are thought to be responsible for a threshold in tumor formation. We highlight DNA repair, for which experimental evidence has been recently provided to dictate a role in PoDs. In conclusion, from a theoretical perspective it is reasonable to posit that tolerance to low dose levels exists for each requisite step of tumor formation and these tolerance mechanisms are critical in determining thresholds in chemical carcinogenesis. [ABSTRACT FROM AUTHOR]

An essay is presented on adoptions of girl children post the emancipation movement. It offers a history of transracial adoptions and examines the possible role of racial and gender ideologies during 19th century in postemancipation societies. The author relates cases of informal arrangements of adoptions.

A closed subgroup of a semisimple algebraic group is called irreducible if it lies in no proper parabolic subgroup. In this paper we classify all irreducible subgroups of exceptional algebraic groups G which are connected, closed and simple of rank at least 2. Consequences are given concerning the representations of such subgroups on various G -modules: for example, with one exception, the conjugacy classes of irreducible simple connected subgroups of rank at least 2 are determined by their composition factors on the adjoint module of G . [ABSTRACT FROM AUTHOR]

The article discusses research which was conducted to examine the mediating role of drive for muscularity and social physique anxiety (SPA) in the perceived muscular male ideal physique and muscle dysmorphia relationship in weight training men. Researchers evaluated 146 men who participated in weight training. They found that perceived ideal physique predicted muscle dysmorphia and size/symmetry concerns and physique protection.

Recent evidence has challenged the default assumption that all DNA-reactive alkylating agents exhibit a linear dose-response. Emerging evidence suggests that the model alkylating agents methyl- and ethylmethanesulfonate and methylnitrosourea (MNU) and ethylnitrosourea observe a nonlinear dose-response with a no observed genotoxic effect level (NOGEL). Follow-up mechanistic studies are essential to understand the mechanism of cellular tolerance and biological relevance of such NOGELs. MNU is one of the most mutagenic simple alkylators. Therefore, understanding the mechanism of mutation induction, following low-dose MNU treatment, sets precedence for weaker mutagenic alkylating agents. Here, we tested MNU at 10-fold lower concentrations than a previous study and report a NOGEL of 0.0075 µg/ml (72.8nM) in human lymphoblastoid cells, quantified through the hypoxanthine (guanine) phosphoribosyltransferase assay (OECD 476). Mechanistic studies reveal that the NOGEL is dependent upon repair of O6-methylguanine (O6MeG) by the suicide enzyme O6MeG-DNA methyltransferase (MGMT). Inactivation of MGMT sensitizes cells to MNU-induced mutagenesis and shifts the NOGEL to the left on the dose axis. [ABSTRACT FROM AUTHOR]

Infidelity is a common experience within romantic relationships and is closely linked with relationship dissolution and well-being. Using an intersectionality theoretical framework, we undertook a systematic review of the infidelity literature in flagship journals associated with the disciplines of the International Association for Relationship Research. Our review includes findings from 162 published empirical articles. We identified several themes within the infidelity literature, including: individual, interpersonal, and contextual predictors; outcomes and reactions; beliefs and attitudes; prevalence; and conceptualization. We also found that the infidelity literature primarily utilizes participants who are White, heterosexual, cisgender individuals who reside in the United States or Canada. Moreover, researchers were limited in information they provided about participants' identities so in most articles it was difficult to assess many dimensions of identity. Ultimately, these findings limit our ability to apply an intersectional framework. We argue that researchers should extend the research they cite, collect richer demographic data, expand their samples (especially beyond White heterosexual cisgender American college students), and consider the sociohistorical context of their participants (e.g., the particular social circumstances and historical forces which shape individuals' lived experiences). For example, scholars using an intersectional framework would explain their participants' relationship experiences through a lens which includes systems of sexism, racism, heterosexism, cissexism, classism, etc., in conjunction with individual and interpersonal factors. [ABSTRACT FROM AUTHOR]

Nearly half of all pregnancies in the United States are unintended. These pregnancies likely represent a substantial cost to taxpayers, but national-level estimates of these public costs have been lacking. Taxpayer spending on unintended pregnancy is measured by multiplying estimates of the 2001 incidence of publicly financed unintended pregnancy outcomes (abortions, fetal losses, births and need for infant medical care) by average per-incident costs. Public savings that would result from preventing unintended pregnancies are estimated by assuming that the prevention of an unwanted pregnancy would save the full cost of financing the pregnancy, while the prevention of a mistimed pregnancy would save the cost of financing the pregnancy today minus the present value of the cost of financing the pregnancy when it eventually occurs. Lower-bound, mean and upper-bound estimates of the annual cost of unintended pregnancy are, respectively, $9.6 billion, $11.3 billion and $12.6 billion. Corresponding estimates of the savings that would accrue to taxpayers by preventing unintended pregnancies are $4.7 billion, $5.6 billion and $6.2 billion. The mean estimate of the taxpayer cost per publicly subsidized unintended pregnancy is $9,000; the prevention of such a pregnancy would save taxpayers about half that amount. The prevention of unintended pregnancy represents an important opportunity for the public to reap substantial savings, especially given the current fiscal climate. The enactment or expansion of cost-effective policies to prevent unintended pregnancies is therefore a timely and sensible strategy. [ABSTRACT FROM AUTHOR]

Abstract: An alternative method to calculate the low frequency capacitance between transformer turns for use in multi-conductor transmission line modeling (MTL) of transformers during high frequency transients is presented. This paper makes use of both 3D and 2D finite element simulation to more accurately calculate the capacitances than can be done by closed form equations with simplifying assumptions while avoiding the computational difficulties involved in the three dimensional analysis of a transformer on the turn to turn level. The method is demonstrated on an arbitrary transformer with few enough turns to readily compute 3D turn-level capacitance for comparison. It is then applied to a real transformer. The results are used to calculate the terminal capacitance which is compared to experimental measurement and found to be within 5% of the measured value. [ABSTRACT FROM AUTHOR]

Isabel Sawhill, Adam Thomas, and Emily Monea believe that given the well-documented costs of nonmarital births to the children and parents in fragile families, as well as to society as a whole, policy makers' primary goal should be to reduce births to unmarried parents. The authors say that the nation's swiftly rising nonmarital birth rate has many explanations—a cultural shift toward acceptance of unwed childbearing; a lack of positive alternatives to motherhood among the less advantaged; a sense of fatalism or ambivalence about pregnancy; a lack of marriageable men; limited access to effective contraception; a lack of knowledge about contraception; and the difficulty of using contraception consistently and correctly. Noting that these explanations fall generally into three categories—motivation, knowledge, and access—the authors discuss policies designed to motivate individuals to avoid unintended pregnancies, to improve their knowledge about contraception, and to remove barriers to contraceptive access. Some motivational programs, such as media campaigns, have been effective in changing behavior. Some, but not all, sex education programs designed to reduce teen pregnancy have also been effective at reducing sexual activity or increasing contraceptive use, or both. Programs providing access to subsidized contraception have also been effective and would be even more so if they could increase the use not just of contraceptives, but of long-acting, reversible contraceptive methods such as intrauterine devices (IUDs) and implants. Finally, the authors present simulations of the costs and effects of three policy initiatives—a mass media campaign that encourages men to use condoms, a teen pregnancy prevention program that discourages sexual activity and educates participants about proper contraceptive use, and an expansion in access to Medicaid-subsidized contraception. All three have benefit-cost ratios that are comfortably greater than one, making them excellent social investments that can actually save taxpayer dollars. [ABSTRACT FROM AUTHOR]

Abstract: Voxel-Based Morphometry (VBM) has been used for several years to study differences in brain structure between populations. Recently, a longitudinal version of VBM has been used to show changes in gray matter associated with relatively short periods of training. In the present study we use fMRI and three different standard implementations of longitudinal VBM: SPM2, FSL, and SPM5 to assess functional and structural changes associated with a simple learning task. Behavioral and fMRI data clearly showed a significant learning effect. However, initially positive VBM results were found to be inconsistent across minor perturbations of the analysis technique and ultimately proved to be artifactual. When alignment biases were controlled for and recommended statistical procedures were used, no significant changes in grey matter density were found. This work, initially intended to show structural and functional changes with learning, rather demonstrates some of the potential pitfalls of existing longitudinal VBM methods and prescribes that these tools be applied and interpreted with extreme caution. [Copyright &y& Elsevier]

Sudden changes in the status of an electrical power system involving generation, loading, or fault conditions result in disturbances in the system, which often cause undesired operation. These disturbances propagate through the system in the form of waves in the phase angle of the voltage until they disperse and normal conditions are restored. Electromechanical characteristics of these waves have been modeled in the past through discrete and continuum approaches. In this paper, a simplified method for numerically solving the governing continuum equations is presented. These equations are represented as electromagnetic equations so that software designed for electromagnetics can be used for continuum power systems. The ability to use commercial software leads to several advantages, among them increased flexibility and reduced computational time, as well as avoiding the need to work directly with tensor fields and Gaussian filters. Continuum network equations can be represented as either an electrostatic or magnetostatic problem, while continuum dynamics, such as generator swing equations, can be represented as electric circuits. The proposed model was tested on the highly anisotropic 27-bus New England system and compared with the continuum model of the same system, with comparable results. [ABSTRACT FROM AUTHOR]

The endogenous cannabinoid system plays an important role in the regulation of gastrointestinal function in health and disease. Endocannabinoid levels are regulated by catabolic enzymes. Here, we describe the presence and localization of monoacylglycerol lipase (MGL), the major enzyme responsible for the degradation of 2-arachidonoylglycerol. We used molecular, biochemical, immunohistochemical, and func-tional assays to characterize the distribution and activity of MGL. MGL mRNA was present in rat ileum throughout the wall of the gut. MGL protein was distributed in the muscle and mucosal layers of the ileum and in the duodenum, proximal colon, and distal colon. We observed MGL expression in nerve cell bodies and nerve fibers of the enteric nervous system. There was extensive colocalization of MGL with POP 9.5 and calretinin-immunoreactive neurons, but not with nitric oxide synthase. MGL was also present in the epithelium and was highly expressed in the small intestine. Enzyme activity levels were highest in the duodenum and decreased along the gut with lowest levels in the distal colon. We observed both soluble and membrane- associated enzyme activities. The MGL inhibitor URB6O2 significantly inhibited whole gut transit in mice, an action that was abolished in cannabinoid 1 receptor-deficient mice. In conclusion, MGL is localized in the enteric nervous system where endocannabinoids regulate intestinal motility. MOL is highly expressed in the epithehum, where this enzyme may have digestive or other functions yet to be determined. [ABSTRACT FROM AUTHOR]

What do the half-century decline in U.S. marriage and the attendant rise in single parenthood mean for the economic well-being of children, especially children living in single-parent families? Adam Thomas and Isabel Sawhill show how differing living arrangements can be expected to affect families' economic well-being. Married-parent and cohabiting households, for example, can benefit from economies of scale and from having two adult earners. The availability of child support for single-parent families and the marriage penalties in the tax and transfer system reduce but rarely completely offset the economic benefits of marriage. Consistent with these expectations, national data on family income show that across all races and for a variety of income measures, children in lone-parent families (single-parent households with no cohabiter) have less family income and are more likely to be poor than children in married-parent families. Cohabiting families are generally better off economically than lone-parent families, but considerably worse off than married-parent families. Thomas and Sawhill acknowledge the possibility that the link between family structure and family resources may not be causal. But new research that simulates marriages between existing single mothers and unattached men with similar characteristics suggests that family structure does affect family resources and that child poverty rates would drop substantially if these mothers were to marry. It does not necessarily follow, however, that policymakers ought to, or even can, do anything about family structure. Marriage is not an economic cure-all for the complex problem of child poverty. It would be a mistake for policymakers to focus on promoting marriage to the exclusion of encouraging and rewarding work or addressing problems such as early out-of-wedlock childbearing. Still, Thomas and Sawhill conclude that a continuation of recent declines in single parenthood, linked most recently to declines in teen and out-of-wedlock births, offers great promise for improving the economic welfare of U.S. children. [ABSTRACT FROM AUTHOR]

Application of nutrients to correct nutrient deficiencies in turfgrasses are often based on tissue analysis. Previous research has indicated that near infrared reflectance spectroscopy (NIRS) may be useful in tissue nutrient concentration determination since it requires minimum sample preparation and has been a reliable predictor of N concentration. The objective of this study was to evaluate the reliability of NIRS in determining P, K, Ca, and Mg concentrations in bermudagrass [Cynodon dactylon (L.) Pers. x C. transvaalensis Burtt Davy]. Tissue samples were collected from Florida golf courses, representing different cultivars grown under various conditions and fertilizer regimes. Tissue samples were analyzed using NIRS and traditional wet chemistry (Mehlich-1 extracts analyzed using inductively coupled argon spectrophotometer) before results were statistically compared. Results from wet chemistry analysis averaged 15 % lower than those obtained from NIRS. Although results for certain cultivars and elements were positively correlated ('Tifdwarf' Ca, r² = 0.72; P < 0.01), precision across all cultivars and nutrients was not sufficient (accounted for only 26% of variability) to indicate that NIRS would be an effective management tool for the elements evaluated in this study. [ABSTRACT FROM AUTHOR]

It is becoming clear that the DNA damage response orchestrates an appropriate response to a given level of DNA damage, whether that is cell cycle arrest and repair, senescence or apoptosis. It is plausible that the alternative regulation of the DNA damage response (DDR) plays a role in deciding cell fate following damage. MicroRNAs (miRNAs) are associated with the transcriptional regulation of many cellular processes. They have diverse functions, affecting, presumably, all aspects of cell biology. Many have been shown to be DNA damage inducible and it is conceivable that miRNA species play a role in deciding cell fate following DNA damage by regulating the expression and activation of key DDR proteins. From a clinical perspective, miRNAs are attractive targets to improve cancer patient outcomes to DNA-damaging chemotherapy. However, cancer tissue is known to be, or to become, well adapted to DNA damage as a means of inducing chemoresistance. This frequently results from an altered DDR, possibly owing to miRNA dysregulation. Though many studies provide an overview of miRNAs that are dysregulated within cancerous tissues, a tangible, functional association is often lacking. While miRNAs are well-documented in 'ectopic biology', the physiological significance of endogenous miRNAs in the context of the DDR requires clarification. This review discusses miRNAs of biological relevance and their role in DNA damage response by potentially 'fine-tuning' the DDR towards a particular cell fate in response to DNA damage. MiRNAs are thus potential therapeutic targets/strategies to limit chemoresistance, or improve chemotherapeutic efficacy. • Cell fate following DNA damage is governed by the DNA damage response that facilitates an appropriate response to DNA damage. • The response to damage can either be survival, via cell cycle arrest and DNA repair, or death. • Post-translational modification of key response enzymes play a role in cell fate, both can be influenced by miRNAs. • miRNAs can be pro-survival or pro-death, depending on their effects on damage response enzymes. • It is possible that miRNAs differentially regulate the response enzymes towards a specific cell fate. [ABSTRACT FROM AUTHOR]

We developed a computational pipeline (now provided as a resource) for measuring morphological similarity between cortical surface sulci to construct a sulcal phenotype network (SPN) from each magnetic resonance imaging (MRI) scan in an adult cohort (n = 34,725; 45–82 years). Networks estimated from pairwise similarities of 40 sulci on 5 morphological metrics comprised two clusters of sulci, represented also by the bimodal distribution of sulci on a linear-to-complex dimension. Linear sulci were more heritable and typically located in unimodal cortex, and complex sulci were less heritable and typically located in heteromodal cortex. Aligning these results with an independent fetal brain MRI cohort (n = 228; 21–36 gestational weeks), we found that linear sulci formed earlier, and the earliest and latest-forming sulci had the least between-adult variation. Using high-resolution maps of cortical gene expression, we found that linear sulcation is mechanistically underpinned by trans-sulcal gene expression gradients enriched for developmental processes. [Display omitted] • A pipeline is provided to extract 5 phenotypes for each of 40 sulci from brain MRI • Sulcal phenotype networks consistently find an axis of linear to complex shape • Adult sulcal complexity is linked to heritability, function, and fetal sulcation • Linear sulci demarcate zones of expression for developmentally enriched genes Snyder et al. develop measures of human cortical folding, revealing an axis of linear to complex sulcal shape across the adult cortex. This axis predicts the phased emergence of sulci in utero and boundaries of cortical gene expression, implicating these processes in the formation of mature cortical geometry. [ABSTRACT FROM AUTHOR]

We prove the existence and uniqueness up to conjugacy of a new maximal subgroup of the algebraic group of type E_8 in characteristic 3. This has type F_4, and was missing from previous lists of maximal subgroups produced by Seitz and Liebeck–Seitz. We also prove a result about the finite group H={}^3\!D_4(2), namely that if H embeds in E_8 (in any characteristic p) and has two composition factors on the adjoint module then p=3 and H lies in a conjugate of this new maximal F_4 subgroup. [ABSTRACT FROM AUTHOR]