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CO2 reduction with protons and electrons at a boron-based reaction center.
Borohydrides are widely used reducing agents in chemical synthesis and have emerging energy applications as hydrogen storage materials and reagents for the reduction of CO2. Unfortunately, the high energy cost associated with the multistep preparation of borohydrides starting from alkali metals precludes large scale implementation of these latter uses. One potential solution to this issue is the direct synthesis of borohydrides from the protonation of reduced boron compounds. We herein report reactions of the redox series [Au(B2P2)] n (n = +1, 0, -1) (B2P2, 9,10-bis(2-(diisopropylphosphino)phenyl)-9,10-dihydroboranthrene) and their conversion into corresponding mono- and diborohydride complexes. Crucially, the monoborohydride can be accessed via protonation of [Au(B2P2)]-, a masked borane dianion equivalent accessible at relatively mild potentials (-2.05 V vs. Fc/Fc+). This species reduces CO2 to produce the corresponding formate complex. Cleavage of the formate complex can be achieved by reduction (ca. -1.7 V vs. Fc/Fc+) or by the addition of electrophiles including H+. Additionally, direct reaction of [Au(B2P2)]- with CO2 results in reductive disproportion to release CO and generate a carbonate complex. Together, these reactions constitute a synthetic cycle for CO2 reduction at a boron-based reaction center that proceeds through a B-H unit generated via protonation of a reduced borane with weak organic acids
Extension as a Delivery System for Prevention Programming: Capacity, Barriers, and Opportunities
Implementation of programs that have demonstrated effects on risk and protective factors offers the best chance for documenting long-term program impacts and, in turn, for obtaining sustained funding. Our study explored the capacity of Extension to serve as a delivery system for best practice programs. In a statewide survey of Family Living and 4-H personnel, we assessed perceptions about such programs and Extension\u27s role in delivering them. Results indicate that Extension has significant strengths as a delivery system for best practice programs. Capacity will be enhanced by reducing the perceived dichotomy between prevention programming and traditional Extension programming
Point mutations in a distant sonic hedgehog cis-regulator generate a variable regulatory output responsible for preaxial polydactyly
Owner perceptions of their cat's quality of life when treated with a modified University of Wisconsin-Madison protocol for lymphoma
The objectives of this study were to assess owner perceptions of their cat’s quality of life during treatment for lymphoma with a doxorubicin-containing multi-agent chemotherapy protocol, whether various health-related parameters correlated with quality of life scores, and to assess owner satisfaction with the protocol
Correlates of Not Using Antiretroviral Therapy Among Transwomen Living with HIV: The Unique Role of Personal Competence
Purpose: This study tested three psychosocial measures for their potential to serve as counseling goals for promoting ART to transgender women living with HIV (TWLH).
Methods: Among 69 TWLH, 17.4% were not taking ART; these volunteers were compared to the remainder using multivariate regression analyses.
Results: Only one psychosocial measure achieved significance: Personal Competence (Adjusted Odds Ratio = 0.80, 95% CI = 0.67–0.97, P = 0.02). Because this was a continuous measure, assessed on a 7-point scale, the protective adjusted odds ratio of 0.80 represents a 20% reduction in the odds of not taking ART for each unit of increase in this construct.
Conclusion: Findings suggest a potential counseling goal for TWLH not taking ART
Can custom 3D printed implants successfully reconstruct massive acetabular defects? A 3D-CT assessment
We report on the accuracy, measured with three-dimensional (3D) computed tomography (CT) postoperatively, in positioning custom 3D printed titanium components in patients with large acetabular defects. Twenty patients (13 females and 7 males) received custom-made acetabular implants between 2016 and 2018; the mean age was 66 years (SD = 11.6) and their mean body mass index was 28 (SD = 6.1). The median time to follow up was 25.5 months, range: 12 to 40 months. We describe a comparison method that uses the 3D models of CT-generated preoperative plans and the postoperative CT scans to quantify the discrepancy between planned and achieved component positions. Our primary outcome measures were the 3D-CT-measured difference between planned and achieved a component position in six degrees of freedom: center of rotation (CoR), component rotation, inclination (INC), and version (VER) of the cup. Our secondary outcome measures were: Oxford hip score, walking status, and complication rate. All components (100%) were positioned within 10 mm of planned CoR (in the three planes). Eighteen (95%) components were not rotated by more than 10° compared to the plan. Eleven (58%) components were positioned within 5° of planned cup angle (INC and VER). To date one complication has occurred, a periprosthetic fracture. This is the largest study in which postoperative 3D-CT measurements and clinical outcomes of custom-made acetabular components have been assessed. Accurate pre-op planning and the adoption of custom 3D printed implants show promising results in complex hip revision surgery
Family Diabetes Camp Amidst COVID-19: A Community of Practice Model
Studies have found that youth are experiencing higher anxiety levels than prior to COVID-19, and youth with type 1 diabetes are at higher risk. Medical specialty camps are a type of camp that provide opportunities for youth with chronic illnesses to share common goals, increase socialization, improve camper well-being, and increase knowledge of diabetes management. The program evaluation sought to determine the impact of a campers’ outcomes of independence and perceived competence and familial impact during COVID-19. Over half the participants were at their first diabetes camp and 71% of the campers felt their perceived competence “increased a little bit” because of camp. Over 95% of parents felt that their participation in camp had increased their diabetes knowledge. Qualitative data from parents revealed 2 themes, camp as a meeting place and learning from others. The findings from this study demonstrate that medical specialty camps influence campers’ perceptions of independence and competence and that families play an important role in creating a community of practice
Structural associations of symptomatic knee osteoarthritis
Objective
Structural changes of osteoarthritis (OA) may occur in the absence of pain. In this study, we aimed to identify histopathologic features that are associated with symptomatic knee OA.
Methods
Medial tibial plateaus and synovium samples were obtained at the time of total knee replacement (TKR) surgery for OA (advanced OA group) or were obtained postmortem from subjects who had not sought medical attention for knee pain during the last year of life (non-OA control group). To identify features of OA, we compared the patients with advanced OA with the age-matched non-OA controls (n = 26 per group). To identify OA features associated with symptoms, we compared two additional groups of subjects who were matched for severity of chondropathy (n = 29 per group): patients undergoing TKR for symptomatic OA (symptomatic chondropathy group) and postmortem subjects with similar severity of chondropathy who were asymptomatic during the last year of life (asymptomatic chondropathy group). The histologic features of the samples were graded, and immunoreactivities for macrophages (CD68) and nerve growth factor (NGF) in the synovium were quantified. The cellular localization of synovial NGF was determined by double immunofluorescence analysis.
Results
Advanced OA cases displayed more severe changes in the synovium (synovitis, increased synovial NGF, and CD68-immunoreactive macrophages) and cartilage (loss of cartilage surface integrity, loss of proteoglycan, tidemark breaching, and alterations in chondrocyte morphology) than did the non-OA controls. Synovial NGF was localized predominantly to fibroblasts and to some macrophages. The symptomatic chondropathy group displayed greater levels of synovitis, synovial NGF, and loss of cartilage integrity, in addition to alterations in chondrocyte morphology, than did the asymptomatic chondropathy group (P < 0.05 for each comparison).
Conclusion
Synovitis, increased synovial NGF, alterations in chondrocyte morphology, and loss of cartilage integrity are features of knee OA that may be associated with symptoms
Climate Action In Megacities 3.0
"Climate Action in Megacities 3.0" (CAM 3.0) presents major new insights into the current status, latest trends and future potential for climate action at the city level. Documenting the volume of action being taken by cities, CAM 3.0 marks a new chapter in the C40-Arup research partnership, supported by the City Leadership Initiative at University College London. It provides compelling evidence about cities' commitment to tackling climate change and their critical role in the fight to achieve global emissions reductions
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