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Criegee intermediates, formed by alkene ozonolysis in the troposphere, can react with volatile organic compounds (VOCs). The temperature-dependent kinetics of the reactions between the Criegee intermediate CH2OO and three aliphatic aldehydes, RCHO where R = H, CH3, and C2H5 (formaldehyde, acetaldehyde, and propionaldehyde, respectively), have been studied using a laser flash-photolysis transient absorption spectroscopy technique. The experimental measurements are supported by ab initio calculations at various composite levels of theory that characterize stationary points on the reaction potential and free energy surfaces. As with other reactions of CH2OO with organic carbonyls, the mechanisms involve 1,3-dipolar cycloaddition at the C=O group, over submerged barriers, leading to the formation of 1,2,4-trioxolane secondary ozonides. The bimolecular rate constants of all three reactions decrease with increasing temperature over the range 275-335 K and are characterized by equations of Arrhenius form: k(T) = (7.1 ± 1.5) × 10-14exp((1160 ± 60)/T), (8.9 ± 1.7) × 10-15exp((1530 ± 60)/T), and (5.3 ± 1.3) × 10-14exp((1210 ± 70)/T) cm3 s-1 for HCHO, CH3CHO, and C2H5CHO, respectively. Based on estimated concentrations of CH2OO, the reactions with aldehydes are unlikely to play a significant role in the atmosphere.

Recent statistics found the prevalence of dyslexia in UK medical schools to be 7%, sitting below the national prevalence of 10%. The factors contributing to this discrepancy are currently unknown, but may result from an interplay of individual and systemic barriers to entering medicine. This collaborative, analytic autoethnography aimed to use the experiences of 'Meg', a fourth-year medical student who was diagnosed as dyslexic whilst at medical school, to explore how the lack of a diagnosis during the admissions process may have impacted her journey into medicine. The data were collected using reflective writing and an interview before conducting a thematic analysis. Our analysis resulted in the construction of two meta-themes, relating to the negative emotional impact of not having a diagnosis and feelings of inferiority. Seven themes were also constructed. Some explored how Meg's personal experience of undiagnosed dyslexia acted as a barrier to entering medicine. Others explored the impact of external factors, such as socio-economic background and the provision of support, on an individual's chance of successfully applying to medical school. Finally, we explored the inadvertent impact undiagnosed (and unrecognised) dyslexia had on Meg's life course, including how medicine-specific aptitude tests, such as the BMAT and UKCAT, may have contributed to this. These results provide a unique window into the culture of applying to medical school as an undiagnosed dyslexic person, whilst discussing the need for medical schools to consider how their admissions processes may inadvertently disadvantage undiagnosed dyslexic applicants.

Though there is a growing body of literature on the kinetics of CIs with simple carbonyls, CI reactions with functionalized carbonyls such as hydroxyketones remain unexplored. In this work, the temperature-dependent kinetics of the reactions of CH2OO with two hydroxyketones, hydroxyacetone (AcOH) and 4-hydroxy-2-butanone (4H2B), have been studied using a laser flash photolysis transient absorption spectroscopy technique and complementary quantum chemistry calculations. Bimolecular rate constants were determined from CH2OO loss rates observed under pseudo-first-order conditions across the temperature range 275-335 K. Arrhenius plots were linear and yielded T-dependent bimolecular rate constants: kAcOH(T) = (4.3 ± 1.7) × 10-15 exp[(1630 ± 120)/T] and k4H2B(T) = (3.5 ± 2.6) × 10-15 exp[(1700 ± 200)/T]. Both reactions show negative temperature dependences and overall very similar rate constants. Stationary points on the reaction energy surfaces were characterized using the composite CBS-QB3 method. Transition states were identified for both 1,3-dipolar cycloaddition reactions across the carbonyl and 1,2-insertion/addition at the hydroxyl group. The free-energy barriers for the latter reaction pathways are higher by ∼4-5 kcal mol-1, and their contributions are presumed to be negligible for both AcOH and 4H2B. The cycloaddition reactions are highly exothermic and form cyclic secondary ozonides that are the typical primary products of Criegee intermediate reactions with carbonyl compounds. The reactivity of the hydroxyketones toward CH2OO appears to be similar to that of acetaldehyde, which can be rationalized by consideration of the energies of the frontier molecular orbitals involved in the cycloaddition. The CH2OO + hydroxyketone reactions are likely too slow to be of significance in the atmosphere, except at very low temperatures.

Abstract: Addressing sustainable energy storage remains crucial for transitioning to renewable sources. While Li‐ion batteries have made significant contributions, enhancing their capacity through alternative materials remains a key challenge. Micro‐sized silicon is a promising anode material due to its tenfold higher theoretical capacity compared to conventional graphite. However, its substantial volumetric expansion during cycling impedes practical application due to mechanical failure and rapid capacity fading. A novel approach is proposed to mitigate this issue by incorporating trace amounts of aluminum into the micro‐sized silicon electrode using ball milling. Density functional theory (DFT) is employed to establish a theoretical framework elucidating how grain boundary sliding, a key mechanism involved in preventing mechanical failure is facilitated by the presence of trace aluminum at grain boundaries. This, in turn, reduces stress accumulation within the material, reducing the likelihood of failure. To validate the theoretical predictions, capacity retention experiments are conducted on undoped and Al‐doped micro‐sized silicon samples. The results demonstrate significantly reduced capacity fading in the doped sample, corroborating the theoretical framework and showcasing the potential of aluminum doping for improved Li‐ion battery performance.

Models estimating decomposition rates of dead wood across space and time are mainly based on studies carried out in temperate zones where microbes are dominant drivers of decomposition. However, most dead wood biomass is found in tropical ecosystems, where termites are also important wood consumers. Given the dependence of microbial decomposition on moisture with termite decomposition thought to be more resilient to dry conditions, the relative importance of these decomposition agents is expected to shift along gradients in precipitation that affect wood moisture. Here, we investigated the relative roles of microbes and termites in wood decomposition across precipitation gradients in space, time and with a simulated drought experiment in tropical Australia. We deployed mesh bags with non-native pine wood blocks, allowing termite access to half the bags. Bags were collected every 6 months (end of wet and dry seasons) over a 4-year period across five sites along a rainfall gradient (ranging from savanna to wet sclerophyll to rainforest) and within a simulated drought experiment at the wettest site. We expected microbial decomposition to proceed faster in wet conditions with greater relative influence of termites in dry conditions. Consistent with expectations, microbial-mediated wood decomposition was slowest in dry savanna sites, dry seasons and simulated drought conditions. Wood blocks discovered by termites decomposed 16–36% faster than blocks undiscovered by termites regardless of precipitation levels. Concurrently, termites were 10 times more likely to discover wood in dry savanna compared with wet rainforest sites, compensating for slow microbial decomposition in savannas. For wood discovered by termites, seasonality and drought did not significantly affect decomposition rates. Taken together, we found that spatial and seasonal variation in precipitation is important in shaping wood decomposition rates as driven by termites and microbes, although these different gradients do not equally impact decomposition agents. As we better understand how climate change will affect precipitation regimes across the tropics, our results can improve predictions of how wood decomposition agents will shift with potential for altering carbon fluxes. Read the free Plain Language Summary for this article on the Journal blog.

Abstract Platelets are key mediators of atherothrombosis, yet, limited tools exist to identify individuals with a hyperreactive platelet phenotype. In this study, we investigate the association of platelet hyperreactivity and cardiovascular events, and introduce a tool, the Platelet Reactivity ExpreSsion Score (PRESS), which integrates platelet aggregation responses and RNA sequencing. Among patients with peripheral artery disease (PAD), those with a hyperreactive platelet response (>60% aggregation) to 0.4 µM epinephrine had a higher incidence of the 30 day primary cardiovascular endpoint (37.2% vs. 15.3% in those without hyperreactivity, adjusted HR 2.76, 95% CI 1.5–5.1, p = 0.002). PRESS performs well in identifying a hyperreactive phenotype in patients with PAD (AUC [cross-validation] 0.81, 95% CI 0.68 –0.94, n = 84) and in an independent cohort of healthy participants (AUC [validation] 0.77, 95% CI 0.75 –0.79, n = 35). Following multivariable adjustment, PAD individuals with a PRESS score above the median are at higher risk for a future cardiovascular event (adjusted HR 1.90, CI 1.07–3.36; p = 0.027, n = 129, NCT02106429). This study derives and validates the ability of PRESS to discriminate platelet hyperreactivity and identify those at increased cardiovascular risk. Future studies in a larger independent cohort are warranted for further validation. The development of a platelet reactivity expression score opens the possibility for a personalized approach to antithrombotic therapy for cardiovascular risk reduction.

As anti-oppressive pedagogies gain increasing prominence in teacher education, there is a need to examine how preservice teachers understand and implement anti-oppressive frameworks. The role of the university supervisor is uniquely well-positioned to allow for insight into preservice teacher pedagogical practices; however, this role is grossly understudied. This study explores how the university supervisor fosters White preservice teachers' theoretical and historical understandings of oppression, as well as the supervisor's role in the negotiation between preservice teacher identity and implementations of anti-oppressive pedagogies. This study utilizes data from preservice teachers' observations and reflections, and positions the university supervisor as an autoethnographic educator-researcher in order to understand the White supervisor's own anti-oppressive practices. Drawing on Critical Whiteness Studies informed by intersectionality, we present two vignettes that illuminate the interplay between identity, anti-oppressive teaching, and the university supervisor. This research brings a new and pertinent lens to the field of education.

Ice-nucleating particles (INPs) are rare atmospheric aerosols that initiate primary ice formation, but accurately simulating their concentrations and variability in large-scale climate models remains a challenge. Doing so requires both simulating major particle sources and parameterizing their ice nucleation (IN) efficiency. Validating and improving model predictions of INP concentrations requires measuring their concentrations delineated by particle type. We present a method to speciate INP concentrations into contributions from dust, sea spray aerosol (SSA), and bioaerosol. Field campaign data from Bodega Bay, California, showed that bioaerosols were the primary source of INPs between -12° and -20°C, while dust was a minor source and SSA had little impact. We found that recent parameterizations for dust and SSA accurately predicted ambient INP concentrations. However, the model did not skillfully simulate bioaerosol INPs, suggesting a need for further research to identify major factors controlling their emissions and INP efficiency for improved representation in models.

Abstract The severity of bacterial pneumonia can be worsened by impaired innate immunity resulting in ineffective pathogen clearance. We describe a mitochondrial protein, aspartyl-tRNA synthetase (DARS2), which is released in circulation during bacterial pneumonia in humans and displays intrinsic innate immune properties and cellular repair properties. DARS2 interacts with a bacterial-induced ubiquitin E3 ligase subunit, FBXO24, which targets the synthetase for ubiquitylation and degradation, a process that is inhibited by DARS2 acetylation. During experimental pneumonia, Fbxo24 knockout mice exhibit elevated DARS2 levels with an increase in pulmonary cellular and cytokine levels. In silico modeling identified an FBXO24 inhibitory compound with immunostimulatory properties which extended DARS2 lifespan in cells. Here, we show a unique biological role for an extracellular, mitochondrially derived enzyme and its molecular control by the ubiquitin apparatus, which may serve as a mechanistic platform to enhance protective host immunity through small molecule discovery.

We describe a patient diagnosed with a metastatic adenocarcinoma of Müllerian origin, harboring a BRAF V600E mutation, ten years after being treated for a serous borderline tumor (SBOT). While BRAF mutations in the setting of SBOTs are common, they have been typically associated with a low chance of transformation or recurrence. The therapeutic approach, which combined hormone inhibition with receptor tyrosine kinase inhibitors (dabrafenib and trametinib), has demonstrated notable and enduring efficacy. This is clinically evidenced through serial PET-CT scans with sustained responses and extended progression-free survival, and serologically confirmed by monitoring CA-125 levels. This case demonstrates the critical role of early next-generation sequencing in detecting actionable molecular changes in rare cancers and possible metastases. It provides valuable insights into treating uncommon Müllerian adenocarcinomas and underscores the importance of targeted therapies in achieving long-lasting treatment outcomes.

Temperature-dependent rate constants for the reactions of CH2OO with acetone (Ac), biacetyl (BiAc), and acetylacetone (AcAc) have been measured over the range 275–335 K using a flash photolysis, transient absorption spectroscopy technique. The measurements were performed at a total pressure of ∼80 Torr in N2 bath gas, which corresponds to the high-pressure limit for these reactions. All three reactions show linear Arrhenius plots with negative temperature dependences. Rate constants increase in the order Ac

Here we provide the 'Global Spectrum of Plant Form and Function Dataset', containing species mean values for six vascular plant traits. Together, these traits -plant height, stem specific density, leaf area, leaf mass per area, leaf nitrogen content per dry mass, and diaspore (seed or spore) mass - define the primary axes of variation in plant form and function. The dataset is based on ca. 1 million trait records received via the TRY database (representing ca. 2,500 original publications) and additional unpublished data. It provides 92,159 species mean values for the six traits, covering 46,047 species. The data are complemented by higher-level taxonomic classification and six categorical traits (woodiness, growth form, succulence, adaptation to terrestrial or aquatic habitats, nutrition type and leaf type). Data quality management is based on a probabilistic approach combined with comprehensive validation against expert knowledge and external information. Intense data acquisition and thorough quality control produced the largest and, to our knowledge, most accurate compilation of empirically observed vascular plant species mean traits to date.

Background: Right hemisphere communication disorders are neither consistently labelled nor adequately defined. Labels associated with right hemisphere brain damage (RHD) are broad and fail to capture the essence of communication challenges needed for stroke-related service provisions. Determination of rehabilitation needs and best-practice guidelines for the education, management and functional improvement of communication disorders after RHD are all predicated on an apt diagnostic label and disorder characteristics. Aims: In this paper "apragmatism" is proposed as a potential communication-specific diagnostic label for the impairments in communication that occur after RHD. In particular, the researchers aimed: (1) to establish an operational definition of apragmatism; and (2) to describe the linguistic, paralinguistic and extralinguistic communication deficits under the umbrella term "apragmatism." Methods & Procedures: An international collaborative of researchers with expertise in RHD followed a multilevel approach to consider the utility of apragmatism as a diagnostic label. Adopting the relational approach to concept mapping, the researchers engaged in a series of group meetings to complete four levels of mapping: (1) identify and review, (2) define, (3) expert discussion and (4) label determination. Main Contribution: Apragmatism was established as a suitable diagnostic label for the impairments in communication associated with RHD. The paper offers an operational definition and description of the linguistic, paralinguistic and extralinguistic features of apragmatism through evidence summaries and examples from people with RHD retrieved from the RHDBank. Conclusions & Implications: The adoption of the term apragmatism offers an opportunity to capture the hallmark of RHD communication deficits. The use of the term is recommended when referencing the pragmatic language impairments in this population. Apragmatism, which may co-occur with or be exacerbated by cognitive impairments, can interfere with the ability to interpret and convey intended meaning and impact the lives of right hemisphere stroke survivors and their families.

Abstract Background To enhance the impact of interventions, it is important to understand how intervention engagement relates to study outcomes. We report on the level of implementation and engagement with the SMART Work & Life (SWAL) programme (delivered with (SWAL plus desk) and without a height-adjustable desk (SWAL)) and explore the effects of different levels of this on change in daily sitting time in comparison to the control group. Methods The extent of intervention delivery by workplace champions and the extent of engagement by champions and participants (staff) with each intervention activity was assessed by training attendance logs, workplace champion withdrawal dates, intervention activities logs and questionnaires. These data were used to assess whether a cluster met defined criteria for low, medium, or high implementation and engagement or none of these. Mixed effects linear regression analyses tested whether change in sitting time varied by: (i) the number of intervention activities implemented and engaged with, and (ii) the percentage of implementation and engagement with all intervention strategies. Results Workplace champions were recruited for all clusters, with 51/52 (98%) attending training. Overall, 12/27 (44.4%) SWAL and 9/25 (36.0%) SWAL plus desk clusters implemented all main intervention strategies. Across remaining clusters, the level of intervention implementation varied. Those in the SWAL (n = 8 (29.6%) clusters, 80 (32.1%) participants) and SWAL plus desk (n = 5 (20.0%) clusters, 41 (17.1%) participants) intervention groups who implemented and engaged with the most intervention strategies and had the highest percentage of cluster implementation and engagement with all intervention strategies sat for 30.9 (95% CI -53.9 to -7.9, p = 0.01) and 75.6 (95% CI -103.6 to -47.7, p

Abstract Background A cluster randomised controlled trial demonstrated the effectiveness of the SMART Work & Life (SWAL) behaviour change intervention, with and without a height-adjustable desk, for reducing sitting time in desk-based workers. Staff within organisations volunteered to be trained to facilitate delivery of the SWAL intervention and act as workplace champions. This paper presents the experiences of these champions on the training and intervention delivery, and from participants on their intervention participation. Methods Quantitative and qualitative feedback from workplace champions on their training session was collected. Participants provided quantitative feedback via questionnaires at 3 and 12 month follow-up on the intervention strategies (education, group catch ups, sitting less challenges, self-monitoring and prompts, and the height-adjustable desk [SWAL plus desk group only]). Interviews and focus groups were also conducted at 12 month follow-up with workplace champions and participants respectively to gather more detailed feedback. Transcripts were uploaded to NVivo and the constant comparative approach informed the analysis of the interviews and focus groups. Results Workplace champions rated the training highly with mean scores ranging from 5.3/6 to 5.7/6 for the eight parts. Most participants felt the education increased their awareness of the health consequences of high levels of sitting (SWAL: 90.7%; SWAL plus desk: 88.2%) and motivated them to change their sitting time (SWAL: 77.5%; SWAL plus desk: 85.77%). A high percentage of participants (70%) reported finding the group catch up session helpful and worthwhile. However, focus groups highlighted mixed responses to the group catch-up sessions, sitting less challenges and self-monitoring intervention components. Participants in the SWAL plus desk group felt that having a height-adjustable desk was key in changing their behaviour, with intrinsic as well as time based factors reported as key influences on the height-adjustable desk usage. In both intervention groups, participants reported a range of benefits from the intervention including more energy, less fatigue, an increase in focus, alertness, productivity and concentration as well as less musculoskeletal problems (SWAL plus desk group only). Work-related, interpersonal, personal attributes, physical office environment and physical barriers were identified as barriers when trying to sit less and move more. Conclusions Workplace champion and participant feedback on the intervention was largely positive but it is clear that different behaviour change strategies worked for different people indicating that a ‘one size fits all’ approach may not be appropriate for this type of intervention. The SWAL intervention could be tested in a broader range of organisations following a few minor adaptations based on the champion and participant feedback. Trial registration ISCRCTN registry (ISRCTN11618007).

The Energy Sciences Network (ESnet) is the high-performance network user facility for the US Department of Energy (DOE) Office of Science (SC) and delivers highly reliable data transport capabilities optimized for the requirements of data-intensive science. In essence, ESnet is the circulatory system that enables the DOE science mission by connecting all of its laboratories and facilities in the US and abroad. ESnet is funded and stewarded by the Advanced Scientific Computing Research (ASCR) program and managed and operated by the Scientific Networking Division at Lawrence Berkeley National Laboratory (LBNL). ESnet is widely regarded as a global leader in the research and education networking community.Throughout 2021, ESnet and the Office of Fusion Energy Sciences (FES) of the DOE SC organized an ESnet requirements review of FES-supported activities. Preparation for these events included identification of key stakeholders: program and facility management, research groups, and technology providers. Each stakeholder group was asked to prepare formal case study documents about their relationship to the FES program to build a complete understanding of the current, near-term, and long-term status, expectations, and processes that will support the science going forward.

Background: Cognitive-communication disorders (CCDs) are common in the traumatic brain injury (TBI) population. Despite this, there has been limited research that explores the long-term impacts of reduced cognitive-communication functioning on daily life for this population. Aims: To identify the long-term impacts of cognitive-communication impairment as reported by adults with TBI and their significant others. Methods & Procedures: A qualitative descriptive approach grounded in phenomenology was used. Semi-structured, one-on-one interviews were conducted with adults with CCDs following TBI (n = 16) and their significant others (n = 12) to explore their lived experiences. Outcomes & Results: Reflexive thematic analysis revealed an overarching theme of 'The pervasive and unyielding impacts of cognitive-communication changes on daily life following TBI'. Within this overarching theme, three subthemes were identified: (1) self-awareness of communication changes; (2) fatigue; and (3) self-identity and life roles. Conclusion & Implications: The findings from this study highlight the long-term negative impacts of reduced cognitive-communication functioning on daily life. Health professionals supporting this population should consider ways to reduce the significant impact CCDs have on the lives of adults following TBI and their significant others. In addition, the findings highlight the importance of long-term rehabilitation services following TBI, with further research needed that explores how these services can be optimised.

Abstract Identification of long‐term calcium channel blocker (CCB) responders with acute vasodilator challenge is critical in the evaluation of patients with pulmonary arterial hypertension. Currently there is no standardized approach for use of supplemental oxygen during acute vasodilator challenge. In this retrospective analysis of patients identified as acute vasoresponders, treated with CCBs, all patients had hemodynamic measurements in three steps: (1) at baseline; (2) with 100% fractional inspired oxygen; and (3) with 100% fractional inspired oxygen plus inhaled nitric oxide (iNO). Those meeting the definition of acute vasoresponsiveness only after first normalizing for the effects of oxygen in step 2 were labeled “iNO Responders.” Those who met the definition of acute vasoresponsiveness from a combination of the effects of 100% FiO2 and iNO were labeled “oxygen responders.” Survival, hospitalization for decompensated right heart failure, duration of CCB monotherapy, and functional data were collected. iNO responders, when compared to oxygen responders, had superior survival (100% vs. 50.1% 5‐year survival, respectively), fewer hospitalizations for acute decompensated right heart failure (0% vs. 30.4% at 1 year, respectively), longer duration of CCB monotherapy (80% vs. 52% at 1 year, respectively), and superior 6‐min walk distance. Current guidelines for acute vasodilator testing do not standardize oxygen coadministration with iNO. This study demonstrates that adjusting for the effects of supplemental oxygen before assessing for acute vasoresponsiveness identifies a cohort with superior functional status, tolerance of CCB monotherapy, and survival while on long‐term CCB therapy.

BackgroundSuicide is a major cause of mortality in the United States, accounting for 14.5 deaths per 100,000 population. Many emergency department (ED) visits in the United States are due to attempted suicides. Suicide attempts predict subsequent completed suicides. Socioeconomic factors, such as community-level socioeconomic deprivation, significantly affect many traditional risk factors for attempted suicides and suicides.AimTo determine the association between community-level socioeconomic deprivation and ED visits for attempted suicide in Maryland.MethodsA retrospective analysis of attempted suicides in the Maryland State Emergency Department Database from January 2018 to December 2020. Community-level socioeconomic deprivation was measured using the Distress Community Index (DCI). Multivariate regression analyses were conducted to identify the association between DCI and attempted suicides/self-harm.ResultsThere were 3,564,987 ED visits reported in the study period, with DCI data available for 3,236,568 ED visits; 86.8% were younger than 45 years, 64.8% were females, and 54.6% non-Hispanic Whites. Over the study period, the proportion of ED visits due to attempted suicide was 0.3%. In the multivariate logistic regression, compared to prosperous zones, those in comfortable (OR = 0.80, 95% CI: 0.73–0.88, p