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91.
92.
ABSTRACT

Purpose

The aim of the present study was to assess the association between levels of physical activity (PA) and the presence of cataracts in people aged 15–69 years residing in Spain.  相似文献   
93.
Abstract

Background: Increasing access to buprenorphine treatment is a critical tool for addressing the opioid epidemic in the United States. In 2016, a federal policy change allowed physicians who meet specific requirements to treat up to 275 concurrent buprenorphine patients. This study examines state-level measures of buprenorphine treatment supply over 21?months since this policy change and estimates associations between the supply of 275-patient waivers and state characteristics. Methods: Monthly state-level measures of the number of physicians holding the 275-patient waiver per 100,000 residents were constructed from September 2016 to May 2018 using the Drug Enforcement Agency’s Controlled Substance Act database. State characteristics were obtained from publicly available sources. Mixed-effects regression models were estimated to examine change over time. Results: During the 21-month period, the number of physicians waivered to treat 275 patients increased from 153 to 4009 physicians. The mean supply of 275-patient physicians per 100,000 state residents significantly increased from 0.07 (SD?=?0.21) in September 2016 to 1.43 (SD?=?1.08) in May 2018 (t?=??9.84, df?=?50, P?<?.001). The final mixed-effects regression model indicated that Census division and the preexisting supply of 100-patient waivered physicians were correlated with the rate of growth in 275-patient waivers over the study period. Conclusions: Although uptake of the 275-patient waiver has exceeded initial projections, growth is uneven across the United States. Unequal patterns of growth pose a challenge to efforts to increase treatment availability as a means of addressing the opioid epidemic.  相似文献   
94.
Electrocatalytic generation of H2 is challenging in neutral pH water, where high catalytic currents for the hydrogen evolution reaction (HER) are particularly sensitive to the proton source and solution characteristics. A tris(hydroxymethyl)aminomethane (TRIS) solution at pH 7 with a [2Fe-2S]-metallopolymer electrocatalyst gave catalytic current densities around two orders of magnitude greater than either a more conventional sodium phosphate solution or a potassium chloride (KCl) electrolyte solution. For a planar polycrystalline Pt disk electrode, a TRIS solution at pH 7 increased the catalytic current densities for H2 generation by 50 mA/cm2 at current densities over 100 mA/cm2 compared to a sodium phosphate solution. As a special feature of this study, TRIS is acting not only as the primary source of protons and the buffer of the pH, but the protonated TRIS ([TRIS-H]+) is also the sole cation of the electrolyte. A species that is simultaneously the proton source, buffer, and sole electrolyte is termed a protic buffer electrolyte (PBE). The structure–activity relationships of the TRIS PBE that increase the HER rate of the metallopolymer and platinum catalysts are discussed. These results suggest that appropriately designed PBEs can improve HER rates of any homogeneous or heterogeneous electrocatalyst system. General guidelines for selecting a PBE to improve the catalytic current density of HER systems are offered.

Molecular hydrogen (H2), a clean-burning and energy-dense fuel source, has been widely discussed as an attractive way to store intermittent energy from solar and wind through water electrolysis (1, 2). Current commercial electrolyzers can be separated into two categories based on their operating pH. The first are acidic polymer electrolyte membrane electrolyzers that work best with rare and expensive platinum-based electrocatalysts for the hydrogen evolution reaction (HER) (3). The second are strongly alkaline electrolyzers that suffer from caustic basic reaction conditions (4). Neutral pH conditions with inexpensive catalysts composed of Earth-abundant elements are a target for practical solar-to-hydrogen fuel devices due to lower cost and fewer safety concerns (5), but achieving fast rates with mild overpotentials under neutral conditions remains a challenge (612). In the pH range from 5 to 9, the electrocatalytic activity of platinum (Pt) itself does not conform to the expected thermodynamic potential shift with pH dependence of −59 mV/pH (13). This is due to the low concentration of the hydronium ion in this pH range and a transition to water as the primary reactant, which has a higher thermodynamic requirement for hydrogen evolution (13). Studies of electrocatalysts using buffers to maintain the pH in this range and ionic salts such as potassium chloride (KCl) to provide ionic strength to ensure high solution conductivity have shown that the buffer can aid the HER activity, presumably by acting as a proton donor (6, 1418). To extend the scope of water-soluble electrocatalysts, biopolymers and bioinspired metallopolymer catalysts have also been studied (7, 12, 1726). Bren and coworkers recently reported particularly enlightening studies of the effects of buffer pKa and structure on the mechanism of the hydrogen evolution reaction for cobalt minienzymes (17, 18).We recently reported a new metallopolymer catalyst system built around a customized [2Fe-2S] catalyst site with a bridging aryldithiolato ligand which exhibits remarkable catalytic activity, air stability, and chemical stability (21). The electrocatalytic mechanism of the [2Fe-2S] catalysts with aryldithiolato ligands is known from previous studies and these catalysts operate at rates of 105 s−1 and faster (2730). The readily synthesized and water-soluble metallopolymer composed of tertiary amine side-chain groups, PDMAEMA-g-[2Fe-2S] (Fig. 1), approached the current density of Pt operating in neutral water under the same conditions and matched the Faradaic yield (97 ± 3%) (21). Although the detailed structural and mechanistic causality of these profound improvements for these metallopolymer electrocatalysts remain subjects of study, the nature of this molecular system is ideal for studying solution effects on the HER reaction at neutral pH for complexes that are normally insoluble in water. In the course of characterizing these electrocatalysts, solutions containing tris(hydroxymethyl)aminomethane (TRIS) at pH 7 were discovered to be exceptionally advantageous to the catalytic rate. In contrast to the few previous studies of TRIS buffer with electrocatalysts (14, 15, 18), we utilized TRIS at a high concentration. At pH 7, TRIS is sufficiently in the cationic protonated form that additional electrolyte such as KCl is not needed for conductance. This important distinction from conventional studies allows TRIS to simultaneously play the roles of pH buffer, proton source, and sole electrolyte. There is precedence in employing buffers in a manner in which they are the sole electrolyte (7, 3134). Referring to such species simply as a “buffer” or as an “electrolyte” is inadequate in representing the three functions including proton source. For the purposes of this paper we term a species that serves all three functions a protic buffer electrolyte (PBE). In the following discussion, a TRIS PBE solution is one in which [TRIS-H]+Cl is the sole electrolyte and the cation is a proton source, and a sodium phosphate PBE solution is one in which Na+[H2PO4] is the sole electrolyte and the anion is a proton source.Open in a separate windowFig. 1.(A) Depiction of the 2e electrocatalytic HER with POEGMA-g-[2Fe-2S] and/or PDMAEMA-g-[2Fe-2S] metallopolymers using TRIS or sodium phosphate protic buffer electrolytes at pH 7. (B) Image of POEGMA-g-[2Fe-2S] with MW = 14,216 grown in silico. The [2Fe-2S] active site is in the center of the polymer, blue represents the polymer backbone, and the rest are the oligo(ethylene glycol) side chains. See SI Appendix for the details of modeling and a larger image.One of the key unanswered questions for these new catalyst systems is whether the metallopolymer composition (i.e., amine side-chain groups) or the PBEs are more important to afford this outstanding catalytic activity. Herein we study the effects of PBEs by comparing the HER performances of a standard platinum catalyst and a [2Fe-2S] metallopolymer catalyst in TRIS PBE solutions, sodium phosphate PBE solutions, and a KCl electrolyte solution without a PBE. For this study, nonionic water-soluble metallopolymers were used, which were made using oligo(ethylene glycol) side-chain groups on the polymer to avoid the possibility of contributing effects of the protonated amino groups of PDMAEMA-g-[2Fe-2S] referred to earlier. The metallopolymer catalyst used in this work is designated as POEGMA-g-[2Fe-2S] (Fig. 1). We previously reported that this water-soluble metallopolymer was largely inactive for H2 electrocatalysis at neutral pH in phosphate buffer (22). The current findings suggest that the use of electrolytes composed of inexpensive cationic organic proton donors can be readily applied to any homogeneous or heterogeneous electrocatalyst system as a facile means to enhance HER activity.  相似文献   
95.
ABSTRACT

STEP-UP is a capacity building and training programme for HIV community activists in Europe and Central Asia, led by the European AIDS Treatment Group (EATG). The programme aims to empower a new cohort of HIV activists each year to engage more deeply in HIV activism at local and national levels addressing key themes such as HIV treatment literacy, prevention technologies, living with HIV, project development, clinical trials, patient participation, advocacy and policy landscapes. The expected outcome of the project is that trainees become activists with knowledge of both policy and science who advocate for change to policy and or practice. To assess the impact of the programme on individual graduates, their organisations and the communities they work with, EATG conducted an evaluation of the programme for the period of 2013–2017. The methods used during the assessment were: a desk review of information about the programme; interviews with implementers and trainees; a focus group with trainees; inputs from national and regional networks, activists and references given by trainees; and an online survey of trainees. This article evaluates the lessons learnt and forms a set of recommendations to implement in the design of future editions of STEP-UP.  相似文献   
96.
Consensus has yet to be reached about the prevention and treatment of medication-related osteonecrosis of the jaw (MRONJ), which is a treatment sequela of several antiresorptive therapies and other pharmaceutical interventions. Several epidemiologic studies have identified periodontal disease (PD) as a risk factor for this outcome. Thus, the objective of this systematic review and meta-analysis was to investigate this association and its magnitude. A systematic search in MEDLINE via PubMed, Scopus and ISI Web of Science, and a meta-analysis were undertaken. Observational studies that gathered information regarding prefixed definitions for both outcomes were selected, and the relevant information was then extracted, and their risk of bias was evaluated using the Newcastle-Ottawa Scale. The protocol of the study was registered on PROSPERO (CRD42019125646). The initial search yielded 757 eligible records, of which 12 were deemed adequate for inclusion (5 cohort studies and 7 case-control studies). On a random-effects meta-analysis, the risk of PD in MRONJ-affected sites compared with at-risk non-affected patients was significantly greater, with a risk ratio of 2.75 (95% CI: 1.67-4.52). Nonetheless, from a pooled analysis of three standardized periodontal measures (ie plaque index, clinical attachment loss and probing depth) no significant results were obtained. MRONJ appears to be associated with an increase in prevalence of PD. The direction of this association, and the factors influencing it must be investigated using further prospective data, and likewise, the possibility for using periodontal therapy as a prevention strategy must be looked into. Periodontal screening needs to be made an indispensable requisite for clinicians in order to establish a correct multidisciplinary approach in MRONJ.  相似文献   
97.

Background

Private hospital rooms have a number of potential advantages compared to shared rooms, including reduced noise and increased control over the hospital environment. However, the association of room type with patient experience metrics in total joint arthroplasty (TJA) patients is currently unclear.

Methods

For private versus shared rooms, we compared our institutional Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) scores in patients who underwent primary TJA over a 2-year period. Regression model odds ratios (ORs) were adjusted for surgeon, date of surgery, and length of stay.

Results

Patients in private rooms were more likely to report a top-box score for overall hospital rating (85.6% vs 79.4%, OR = 1.53, P = .011), hospital recommendation (89.3% vs 83.0%, OR = 1.78, P = .002), call button help (76.0% vs 68.7%, OR = 1.40, P = .028), and quietness (70.4% vs 59.0%, OR = 1.78, P < .001). There were no significant differences on surgeon metrics including listening (P = .225), explanations (P = .066), or treatment with courtesy and respect (P = .396).

Conclusion

For patients undergoing TJA, private hospital rooms were associated with superior performance on patient experience metrics. This association appears specific for global and hospital-related metrics, with little impact on surgeon evaluations. With the utilization of HCAHPS data in value-based initiatives, placement of TJA patients in private rooms may lead to increased reimbursement and higher hospital rankings.

Level of Evidence

Level III, retrospective cohort.  相似文献   
98.
Objective: Psychotherapy research commonly utilizes clients’ last session score as an indicator of treatment outcome. We examined whether this last session score is consistent with what would be predicted based on clients’ general trajectory in psychological functioning across sessions. We focused on the unstandardized residual variance at the last session, as this represents the degree to which the session score is divergent (or not) from what is predicted from the previous sessions (i.e., Outcome Stability Index; OSI). Method: The sample included 27,958 clients who attended on average 9.41 sessions. Each session, clients completed the Behavioral Health Measure-20 as a measure of psychological functioning. We converted the unstandardized residual variance for clients’ last session score into a Cohen’s d coefficient to aid in interpretation. Results: The mean OSI was 0.07 (SD?=?0.58), suggesting excellent stability in their last session therapy outcome scores. However, approximately 33% of clients demonstrated poor or extremely problematic stability in their last session therapy outcome scores. Clients who demonstrated poor stability were classified as demonstrating reliable deterioration. Conclusions: Researchers may want to consider reporting OSI to assist readers’ understanding of the stability of therapy outcomes.

Clinical or methodological significance of this article: Therapy outcome scores can vary from session to session, which can influence how we understand therapy outcomes that rely on last session scores. Studies examining therapy outcomes could report the Outcome Stability Index to better contextualize the results.  相似文献   

99.

Background

Comprehensive Care for Joint Replacement (CJR) is a Medicare initiative to test the impact of holding a hospital accountable for services provided during an episode of care for a lower extremity joint arthroplasty on costs and quality. This study examines whether hospital participation in CJR is associated with having programs focused on improving posthospitalization care or reducing costs using a survey of orthopedic surgeons.

Methods

Seventy-three (of 104) orthopedic surgeon members of the Hip Society, a national professional organization of hip surgeons, completed the survey.

Results

Surgeons practicing in CJR hospitals were more likely to report that their hospital had implemented programs focused on improving posthospitalization care or reducing costs. Surgeons in CJR hospitals were significantly more likely to report that the hospital had a narrow network of skilled nursing facilities to enhance care and limit length of stay in skilled nursing facilities (83% vs 47%, P < .01). Surgeons in CJR hospitals were also more likely to report the hospital provides incentives or some type of gainsharing. There were no statistically significant differences in implementation of having programs to reduce costs or improve care during hospitalization.

Conclusion

Participation in CJR is associated with higher utilization of hospital practices aimed at improving postdischarge care and higher utilization of linking surgeon compensation to cost and quality.  相似文献   
100.

Background

Anterior knee pain (AKP) remains a complex issue affecting patient satisfaction after total knee arthroplasty. Several radiographic parameters have been shown to be causative factors with various designs. The aim of this study is to evaluate the known radiographic parameters of AKP and clinical outcomes (ie, AKP) in the setting of a modern prosthesis with an anatomic patella button.

Methods

Between July 2012 and December 2013, 90 total knee arthroplasties received 3 skyline views taken at 30°, 45°, and 60°. A patient-administered questionnaire was administered at 2-year follow-up to assess the incidence of AKP, painless noise, and satisfaction. Radiographs were analyzed for patellofemoral overstuffing, patellar tilt, and patellar displacement, and evaluated the patella resection angle.

Results

On the patient-administered questionnaire, 10 (11.1%) patients reported AKP of a mild-to-moderate nature. Thirty-one had the best view at 30 Merchant views, 24 had best views at 45, and 35 had best views at 60. We found that patellar resection angle correlated with AKP (odds ratio 1.21, P = .044) and painless noise (odds ratio 1.22, P = .034). Patellar displacement and patellofemoral stuffing did not correlate with AKP or painless noise. No radiographic measurements correlated with changes in Knee Society Score pain or function scores or range of motion.

Conclusion

We found that a patellar resection angle correlated with the incidence of AKP and painless noise at 2-year follow-up. We failed to find any correlation with patellofemoral overstuffing, patellar displacement, or patellar tilt with clinical outcomes. We recommend the use of 3 Merchant views to fully evaluate the patellofemoral joint.  相似文献   
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