1,450 research outputs found
Intramolecular C−H Activation of a Bisphenolate(benzene)-Ligated Titanium Dibenzyl Complex. Competing Pathways Involving α-Hydrogen Abstraction and σ-Bond Metathesis
A titanium dibenzyl complex featuring a ligand with two phenolates linked by a benzene-1,3-diyl group was found to undergo thermal decomposition to give toluene and a cyclometalated dimeric complex. The thermal decomposition followed first-order kinetics and was studied at a number of temperatures to determine the activation parameters (ΔH‡ = 27.2(5) kcal/mol and ΔS‡ = −6.2(14) cal/(mol K)). Deuterated isotopologues were synthesized to measure the kinetic isotope effects. The complexes with deuterium in the benzyl methylene positions decomposed more slowly than the protio analogues. Isotopologues of toluene with multiple deuteration positions were observed in the product mixtures. These data are consistent with competing α-abstraction and σ-bond metathesis
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The role of organizational factors in influencing payoffs from computerization
The prevailing understanding of information technology (IT) resources, especially computers, is that their use can independently lead organizations to achieve high levels of performance and result in large productivity payoffs. This notion has been fueled by findings of several studies that examined only the impact large financial investments in IT have on productivity, while neglecting the effi;ct of the larger organizational context
Improving access to primary care:a mixed-methods approach studying a new review appointment system in a Scottish GP practice
A Scottish general practitioner (GP) practice proposed an improvement intervention, shorter pre-bookable ‘review’ appointments, to increase appointment capacity and meet their patients’ demand for appointments. Staff are now able to pre-book these review appointments for patients, guaranteeing that the patient will see the same GP or advanced nurse practitioner (ANP) for both initial and review appointments. By shortening the review appointments, more patients were seen each day, hence the appointment capacity increased. The aim of this project was to examine the impact of the improvement intervention, pre-bookable review appointments, using a mixed-methods approach. Ethnographic methods (non-participant observation, participant observation and eight semistructured interviews with administrative staff) provided qualitative data, to understand the appointment system and to identify areas for further improvement. Quantitative data were then collected to assess: the number of patients receiving ‘on the day’ appointments, with the aim for this to be 95% (outcome measure); by how much the number of appointments available had increased (process measure) and the administrative staff workload (balancing measure). During a 7-week period, 3 months post-intervention, a median of 93% of patients received an ‘on the day’ appointment when they phoned for one between 08:00 and 09:00. The number of appointments available increased by 43%. Administrative staff workload (number of calls received per day) remained the same. Patients prefer being able to book in to see the same GP (continuity of care) and the ability to book in advance. Administrative staff workload decreased in terms of dealing with less frustrated patients. Main suggestions for improvement include introducing later appointments for workers and text reminders for pre-booked (review and online) appointments. The introduction of pre-bookable review appointments improved patient accessibility in the practice. Next steps for improving the appointment system include gaining clinician (GP/ANP) opinions on review appointments and trialling later appointments
Hormone Therapy for Postmenopausal Women with Urinary Incontinence
Postmenopausal women should not receive oral hormone therapy for treatment of urinary incontinence. Hormone therapy is associated with worsening urinary incontinence in postmenopausal women who are incontinent at baseline (Strength of Recommendation [SOR]: A, based on a systematic review) and is associated with an increased risk of developing urinary incontinence in those who are continent at baseline (SOR: A, based on two large randomized controlled trials [RCTs])
Developing Ecological Criteria for Prescribed Fire in South Florida Pine Rockland Ecosystems
The pine rocklands of South Florida, characterized by a rich herbaceous flora with many narrowly endemic taxa beneath an overstory of south Florida slash pine (Pinus elliottii var. densa), are found in three areas: the Miami Rock Ridge of southeastern peninsular Florida, the Lower Florida Keys, and slightly elevated portions of the southern Big Cypress National Preserve. Fire is an important element in these ecosystems, since in its absence the pine canopy is likely to be replaced by dense hardwoods, resulting in loss of the characteristic pineland herb flora. Prescribed fire has been used in Florida Keys pine forests since the creation of the National Key Deer Refuge (NKDR), with the primary aim of reducing fuels. Because fire can also be an effective tool in shaping ecological communities, we conducted a 4-year research study which explored a range of fire management options in NKDR. The intent of the study was to provide the Fish and Wildlife Service and other land managers with information regarding when and where to burn in order to perpetuate these unique forests
Preschoolers’ Psychosocial Problems: In the Eyes of the Beholder? Adding Teacher Characteristics as Determinants of Discrepant Parent–Teacher Reports
In this study, we explored informant characteristics as determinants of parent–teacher disagreement on preschoolers’ psychosocial problems. Teacher characteristics were included in the analyses, in addition to child and parent factors. Psychosocial problems of 732 4-year olds from a Norwegian community sample were assessed by parents and teachers (CBCL-TRF). Furthermore, teachers reported on their education, experience and relationship to the child. Parental stress and psychopathology were also measured. Teachers rated children considerably lower than their parents did, especially on internalizing problems. When teachers rated more child problems, this was strongly associated with conflict in the teacher–child relationship, which predicted disagreement more than other factors. The highest agreement was on boys’ externalizing problems. Girls’ behavior was rated much lower by teachers than boys’ behavior compared to parents’ ratings. Possible teacher perception biases are discussed, such as teacher–child conflict, non-identification of internalizing problems, and same-gender child preference
Robotic Lepidoptery: Structural Characterization of (mostly) Unexpected Palladium Complexes Obtained from High-Throughput Catalyst Screening
In the course of a high-throughput search for optimal combinations of bidentate ligands with Pd(II) carboxylates to generate oxidation catalysts, we obtained and crystallographically characterized a number of crystalline products. While some combinations afforded the anticipated (L-L)Pd(OC(O)R)_2 structures (L-L = bipyridine, tmeda; R = CH_3, CF_3), many gave unusual oligometallic complexes resulting from reactions such as C−H activation (L-L = sparteine), P−C bond cleavage (L-L = 1,2-bis(diphenylphosphino)ethane, and C−C bond formation between solvent (acetone) and ligand (L-L = 1,4-bis(2,6-diisopropylphenyl)-1,4-diaza-1,3-butadiene). These findings illustrate potential pitfalls of screening procedures based on assuming uniform, in situ catalyst self-assembly
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Goal-directed versus outcome-based financial incentives for weight loss among low-income patients with obesity: rationale and design of the Financial Incentives foR Weight Reduction (FIReWoRk) randomised controlled trial.
IntroductionObesity is a major public health challenge and exacerbates economic disparities through employment discrimination and increased personal health expenditures. Financial incentives for weight management may intensify individuals' utilisation of evidence-based behavioural strategies while addressing obesity-related economic disparities in low-income populations. Trials have focused on testing incentives contingent on achieving weight loss outcomes. However, based on social cognitive and self-determination theories, providing incentives for achieving intermediate behavioural goals may be more sustainable than incentivising outcomes if they enhance an individual's skills and self-efficacy for maintaining long-term weight loss. The objective of this paper is to describe the rationale and design of the Financial Incentives foR Weight Reduction study, a randomised controlled trial to test the comparative effectiveness and cost-effectiveness of two financial incentive strategies for weight loss (goal directed vs outcome based) among low-income adults with obesity, as well as compared with the provision of health behaviour change resources alone.Methods and analysisWe are recruiting 795 adults, aged 18-70 years with a body mass index ≥30 kg/m2, from three primary care clinics serving residents of socioeconomically disadvantaged neighbourhoods in New York City and Los Angeles. All participants receive a 1-year commercial weight loss programme membership, self-monitoring tools (bathroom scale, food journal and Fitbit Alta HR), health education and monthly check-in visits. In addition to these resources, those in the two intervention groups can earn up to $750 over 6 months for: (1) participating in an intensive weight management programme, self-monitoring weight and diet and meeting physical activity guidelines (goal-directed arm); or (2) a ≥1.5% to ≥5% reduction in baseline weight (outcome-based arm). To maximise incentive efficacy, we incorporate concepts from behavioural economics, including immediacy of payments and framing feedback to elicit regret aversion. We will use generalised mixed effect models for repeated measures to examine intervention effects on weight at 6, 9 and 12 months.Ethics and disseminationHuman research protection committees at New York University School of Medicine, University of California Los Angeles (UCLA) David Geffen School of Medicine and Olive-View-UCLA Medical Center granted ethics approval. We will disseminate the results of this research via peer-reviewed publications, conference presentations and meetings with stakeholders.Trial registration numberNCT03157713
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