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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.

X-ray scattering experiments using Free Electron Lasers (XFELs) are a powerful tool to determine the molecular structure and function of unknown samples (such as COVID-19 viral proteins). XFEL experiments are a challenge to computing in two ways: i) due to the high cost of running XFELs, a fast turnaround time from data acquisition to data analysis is essential to make informed decisions on experimental protocols; ii) data collection rates are growing exponentially, requiring new scalable algorithms. Here we report our experiences analyzing data from two experiments at the Linac Coherent Light Source (LCLS) during September 2020. Raw data were analyzed on NERSC's Cori XC40 system, using the Superfacility paradigm: our workflow automatically moves raw data between LCLS and NERSC, where it is analyzed using the software package CCTBX. We achieved real time data analysis with a turnaround time from data acquisition to full molecular reconstruction in as little as 10 min -- sufficient time for the experiment's operators to make informed decisions. By hosting the data analysis on Cori, and by automating LCLS-NERSC interoperability, we achieved a data analysis rate which matches the data acquisition rate. Completing data analysis with 10 mins is a first for XFEL experiments and an important milestone if we are to keep up with data collection trends.

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.

Through the years, the range of services involving animals benefiting people, often described as “animal-assisted interventions” (AAIs), has been plagued with confusing and inconsistent taxonomy, terminology, and definitions. This has caused difficulties for the delineation of roles of service providers, for the recipients of services, as well as for the preparation, training, and expectations of the animals that work in different roles. It can be argued that these difficulties have compromised the development of the field in terms of establishing agreed standards of practice, qualifications, and competencies and adopting good animal welfare practices. It has also likely limited the base of evidence, as search terms used to access studies are not consistent, and study protocols are difficult to compare, lacking uniformity in terminology. Additionally, the current terminology cannot accommodate the expansion and diversification of programs in recent years, which is likely to continue as the field evolves. Establishing internationally agreed upon uniform taxonomy, terminology, and definitions is crucial to more accurately reflect the key features of different approaches, to define the scope and competencies for different service providers and their animals, to provide transparency about services for recipients, and to ensure the appropriate preparation, training, and support of the animals that work with them., The recommendations in this article are the result of an international work group that convened over the course of two years. The umbrella term animal-assisted services (AAS) is proposed, defined as services that are facilitated, guided or mediated by a health or human service provider or educator, who works with and maintains the welfare of a specially alongside a specially qualifying animal to provide therapeutic, educational, supportive and/or ameliorative processes aimed at enhancing the well-being of humans. AAS are further categorized into three main areas: treatment, education, and support programs. A recommendation for provider-specific terminology is also suggested. The aim of these proposals is to set clear expectations and boundaries for each specialty of practice, without compromising the richness and diversity of each approach. The adoption of this new umbrella term and its categories is intended to improve clarity for all involved in the receipt and delivery of services, as well as for those who study their effects.

Abstract Background Social isolation and feelings of loneliness are very prevalent in people with neurodegenerative diseases and are associated with a lower quality of life and other negative outcomes. These problems were increased during the COVID-19 pandemic resulting in initiatives to address social isolation. Given the potential benefits of nature-based and animal-assisted intervention strategies (NATAIS), it is crucial to further investigate if and how these strategies might minimize negative effects of social isolation and feelings of loneliness in this population. Therefore, the aim of this project was to develop a research agenda for NATAIS in people with neurodegenerative diseases, especially during challenging times, such as pandemics. Methods This article outlines the process and results of a group concept mapping procedure aimed at developing a research agenda based on a logic model. In total, 19 work group members participated through a combination of in-person and online group meetings. Additionally, face-to-face group sessions were held at two international scientific conferences, during which feedback was solicited from 12 experts in the field of NATAIS and psychogeriatrics. Results The group concept mapping procedure resulted in 14 clusters describing various future research topics, which were further refined and detailed during group discussions. The remaining eleven clusters, encompassing important research themes within the field of NATAIS, were organized into a logic model and summarized into the research agenda. The overarching cluster ‘ethical issues, possible risk factors, and their solutions’ was considered the most relevant during times of increased social isolation, such as during a pandemic, along with the necessity for more accessible NATAIS. Conclusions This project resulted in a research agenda, directing future research and fostering collaboration between practitioners and researchers in the field of NATAIS. Such an enhanced partnership between science and practice has the potential to significantly contribute to the well-being of people with neurodegenerative diseases, in their daily lives and also during pandemics.

We propose and test the proposition that innate personality differences in trait affect explain significant variance in student satisfaction. Using three standard measures of trait affect and data from a student sample (n = 409) of PhD candidates across science, social science and humanities in 63 universities from 20 countries, we find that 24% of variance in student satisfaction is accounted for by trait affect. We also find that both discipline studied and research orientation of university have moderating effects on the relationship between trait affect and student satisfaction. Our findings suggest student satisfaction scores need to be viewed with caution because, in part, they merely reflect individual-level trait affect that--like all innate personality traits--academics, university administrators and education ministers alike are powerless to alter. Our findings indicate that governments, universities and other organisations gathering student satisfaction data could usefully adopt measures to control for trait affect. Our findings also raise the possibility that universities might strategically incorporate innate affect in their student selection criteria to game satisfaction ratings.

This longitudinal study serves as a model for examining and understanding the role of editing and its contributing factors in writing center tutorials. The study quantifies the frequency of and time devoted to editing in over 4,000 writing center tutorials and finds these quantities differ in statistically significant ways when broken down by user groups (gender, student standing, course level, and primary language); tutoring modes (face-to-face, synchronous-online, and asynchronous); and time of student visit relative to project due date. Analysis identifies contributing factors that influence frequency of and time spent on editing in tutorials by these groups, including group membership and their associated editing practices and tutorial habits. The study's findings fill an important gap in our understanding of what takes place in writing center tutorials and have significant implications for tutor training and marketing of writing center services.

Low completion rates amongst students from Black working-class backgrounds remain a persistent challenge to post-apartheid university transformation in South Africa. Notions of universities as colour-blind, meritocratic, and post-racial have developed around a deficit and victim-blaming majoritarian narrative that individualises educational under-achievement, blaming victims and downplaying the complicity of universities in reproducing inequity. This article analyses the narratives of a group of Black working-class students, and academics on their in-depth experiences of educational success and failure in post-apartheid South African universities. Counter-storytelling is employed to foreground and promote the voice and lived experiences of those who often go unheard; and to highlight their narratives as valuable and critical in understanding persistent inequity in higher education. This article looks beyond the fixation on what students from marginalised communities are perceived to lack to reassert a place for institutional context in studying their experiences, to minimise the de-contextualisation of such experiences; and to illuminate areas of universities' complicity in reproducing untenable educational experiences and outcomes for those already in the margins. Participants' counter-stories are presented to deepen our understanding and theorisation of Black working-class students' lived experiences in a manner that enriches the work of researchers, policy makers and practitioners.

The purpose of the current study was to test the longitudinal association between disordered eating symptoms (body dissatisfaction, drive for thinness and bulimia) in adolescence (ages 12, 14, 16, 18, 19) and adulthood (age 40) in a sample of 883 white and Black women. We also investigated moderation by race. Adolescent symptoms at each time point significantly predicted adulthood symptoms for the body dissatisfaction and drive for thinness subscales, for both Black and white women. Bulimia symptoms in adolescence predicted symptoms in adulthood; however, the effect was largely driven by white women. Although moderation was non-significant, among white women, bulimia symptoms at all adolescent time points predicted adulthood bulimia, but among Black women, only symptoms at ages 18 and 19 were predictive of adulthood bulimia. Results suggest that both Black and white women are susceptible to disordered eating and that symptoms emerging in adolescence can potentially follow women into midlife.