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1.
J Am Chem Soc ; 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39051942

RESUMEN

The electronic organization of Frustrated Lewis Pairs (FLPs) allows them to activate strong bonds in mechanisms that are usually free of redox events at the Lewis acidic site. The unique 6d/5f manifold of uranium could serve as an interesting FLP acceptor site, but to date FLP-like catalysis with actinide ions is unknown. In this paper, the catalytic, FLP-like hydrogenation reactivity of trivalent uranium complexes is explored in the presence of base-stabilized silylenes. Comparison to isoelectronic, isostructural lanthanide and thorium complexes lends insight into the electronic factors governing dihydrogen activation. Mechanistic studies of the uranium- and lanthanide-catalyzed hydrogenations are presented, including discussion of likely intermediates. Computational modeling of the f-element complexes, combined with experimental comparison to p-block Lewis acids, elucidates the relevance of steric hindrance to productive reactivity with dihydrogen. Consideration of the complete experimental and theoretical evidence provides a clear picture of the electronic and steric factors governing dihydrogen activation by these FLPs.

2.
Chem Commun (Camb) ; 60(61): 7878-7881, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38984492

RESUMEN

A novel Ta/Os heterobimetallic complex, [Ta(CH2tBu)3(µ-H)3OsCp*], 2, is prepared by protonolysis of Ta(CHtBu)(CH2tBu)3 with Cp*OsH5. Treatment of 2 and its iridium analogue [Ta(CH2tBu)3(µ-H)2IrCp*], 1, with CO2 under mild conditions reveal the efficient cleavage of CO2, driven by the formation of a tantalum oxo species in conjunction with CO transfer to the osmium or iridium fragments, to form Cp*Ir(CO)H2 and Cp*Os(CO)H3, respectively. This bimetallic reactivity diverges from more classical CO2 insertion into metal-X (X = metal, hydride, alkyl) bonds.

3.
Chem Sci ; 15(25): 9784-9792, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38939147

RESUMEN

Transition metal multimetallic complexes have seen intense study due to their unique bonding and potential for cooperative reactivity, but actinide-transition metal (An-TM) species are far less understood. We have synthesized uranium- and thorium-osmium heterometallic polyhydride complexes in order to study An-Os bonding and investigate the reactivity of An-Os interactions. Computational studies suggest the presence of a significant bonding interaction between the actinide center and the four coordinated osmium centers supported by bridging hydrides. Upon photolysis, these complexes undergo intramolecular C-H activation with the formation of an Os-Os bond, while the thorium complex may activate an additional C-H bond of the benzene solvent, resulting in a µ-η1,η1 phenyl ligand across one Th-Os interaction.

4.
Inorg Chem ; 63(24): 11296-11310, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38836624

RESUMEN

We expand upon the synthetic utility of anionic rhenium complex Na[(BDI)ReCp] (1, BDI = N,N'-bis(2,6-diisopropylphenyl)-3,5-dimethyl-ß-diketiminate) to generate several rhenium-phosphorus complexes. Complex 1 reacts in a metathetical manner with chlorophosphines Ph2PCl, MeNHP-Cl, and OHP-Cl to generate XL-type phosphido complexes 2, 3, and 4, respectively (MeNHP-Cl = 2-chloro-1,3-dimethyl-1,3,2-diazaphospholidine; OHP-Cl = 2-chloro-1,3,2-dioxaphospholane). Crystallographic and computational investigations of phosphido triad 2, 3, and 4 reveal that increasing the electronegativity of the phosphorus substituent (C < N < O) results in a shortening and strengthening of the rhenium-phosphorus bond. Complex 1 reacts with iminophosphane Mes*NPCl (Mes* = 2,4,6-tritert-butylphenyl) to generate linear iminophosphanyl complex 5. In the presence of a suitable halide abstraction reagent, 1 reacts with the dichlorophosphine iPr2NPCl2 to afford cationic phosphinidene complex 6+. Complex 6+ may be reduced by one electron to form 6•, a rare example of a stable, paramagnetic phosphinidene complex. Spectroscopic and structural investigations, as well as computational analyses, are employed to elucidate the influence of the phosphorus substituent on the nature of the rhenium-phosphorus bond in 2 through 6. Furthermore, we examine several common analogies employed to understand metal phosphido, phosphinidene, and iminophosphanyl complexes.

5.
Pain ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38916521

RESUMEN

ABSTRACT: This systematic review and meta-analysis critically examined the evidence for peer support interventions to reduce pain and improve health outcomes in community-dwelling adults with chronic musculoskeletal pain (PROSPERO CRD42022356850). A systematic search (inception-January 2023) of electronic databases and grey literature was undertaken to identify relevant randomised controlled trials, with risk of bias and GRADE assessments performed on included studies. Meta-analyses used a generic, inverse-variance, random-effects model, calculating mean difference (MD) or standardised mean difference (SMD). Of 16,445 records identified, 29 records reporting on 24 studies (n = 6202 participants) were included. All evidence had unclear/high risk of bias and low-very low certainty. Peer support interventions resulted in small improvements in pain (medium-term: MD -3.48, 95% CI -6.61, -0.35; long-term: MD -1.97, 95% CI -3.53, -0.42), self-efficacy (medium-term: SMD 0.26, 95% CI 0.16, 0.36; long-term: SMD 0.21, 95% CI 0.07, 0.36), and function (long-term: SMD -0.10, 95% CI -0.19, -0.00) relative to usual care and greater self-efficacy (medium-term: SMD 0.36, 95% CI 0.20, 0.51) relative to waitlist control. Peer support interventions resulted in similar improvement as active (health professional led) interventions bar long-term self-efficacy (MD -0.41, 95% CI -0.77, -0.05), which favoured active interventions. No point estimates reached minimal clinically important difference thresholds. Pooled health service utilisation outcomes showed unclear estimates. Self-management, quality of life, and social support outcomes had mixed evidence. Despite low-very low evidence certainty, peer support interventions demonstrated small improvements over usual care and waitlist controls for some clinical outcomes, suggesting that peer support may be useful as an adjunct to other treatments for musculoskeletal pain.

6.
Inorg Chem ; 63(16): 7177-7188, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38598523

RESUMEN

While synthesizing a series of rhenium-lanthanide triple inverse sandwich complexes, we unexpectedly uncovered evidence for rare examples of end-on lanthanide dinitrogen coordination for certain heavy lanthanide elements as well as for uranium. We begin our report with the synthesis and characterization of a series of trirhenium triple inverse sandwich complexes with the early lanthanides, Ln[(µ-η5:η5-Cp)Re(BDI)]3(THF) (1-Ln, Ln = La, Ce, Pr, Nd, Sm; Cp = cyclopentadienide, BDI = N,N'-bis(2,6-diisopropylphenyl)-3,5-dimethyl-ß-diketiminate). However, as we moved across the lanthanide series, we ran into an unexpected result for gadolinium in which we structurally characterized two products for gadolinium, namely, 1-Gd (analogous to 1-Ln) and a diazenido dirhenium double inverse sandwich complex Gd[(µ-η1:η1-N2)Re(η5-Cp)(BDI)][(µ-η5:η5-Cp)Re(BDI)]2(THF)2 (2-Gd). Evidence for analogues of 2-Gd was spectroscopically observed for other heavy lanthanides (2-Ln, Ln = Tb, Dy, Er), and, in the case of 2-Er, structurally authenticated. These complexes represent the first observed examples of heterobimetallic end-on lanthanide dinitrogen coordination. Density functional theory (DFT) calculations were utilized to probe relevant bonding interactions and reveal energetic differences between both the experimental and putative 1-Ln and 2-Ln complexes. We also present additional examples of novel end-on heterobimetallic lanthanide and actinide diazenido moieties in the erbium-rhenium complex (η8-COT)Er[(µ-η1:η1-N2)Re(η5-Cp)(BDI)](THF)(Et2O) (3-Er) and uranium-rhenium complex [Na(2.2.2-cryptand)][(η5-C5H4SiMe3)3U(µ-η1:η1-N2)Re(η5-Cp)(BDI)] (4-U). Finally, we expand the scope of rhenium inverse sandwich coordination by synthesizing divalent double inverse sandwich complex Yb[(µ-η5:η5-Cp)Re(BDI)]2(THF)2 (5-Yb), as well as base-free, homoleptic rhenium-rare earth triple inverse sandwich complex Y[(µ-η5:η5-Cp)Re(BDI)]3 (6-Y).

7.
Int J Behav Nutr Phys Act ; 21(1): 30, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38481238

RESUMEN

Increasing physical activity in patients offers dual benefits, fostering improved patient health and recovery, while also bolstering healthcare system efficiency by minimizing costs related to extended hospital stays, complications, and readmissions. Wearable activity trackers offer valuable opportunities to enhance physical activity across various healthcare settings and among different patient groups. However, their integration into healthcare faces multiple implementation challenges related to the devices themselves, patients, clinicians, and systemic factors. This article presents the Wearable Activity Tracker Checklist for Healthcare (WATCH), which was recently developed through an international Delphi study. The WATCH provides a comprehensive framework for implementation and evaluation of wearable activity trackers in healthcare. It covers the purpose and setting for usage; patient, provider, and support personnel roles; selection of relevant metrics; device specifications; procedural steps for issuance and maintenance; data management; timelines; necessary adaptations for specific scenarios; and essential resources (such as education and training) for effective implementation. The WATCH is designed to support the implementation of wearable activity trackers across a wide range of healthcare populations and settings, and in those with varied levels of experience. The overarching goal is to support broader, sustained, and systematic use of wearable activity trackers in healthcare, therefore fostering enhanced physical activity promotion and improved patient outcomes.


Asunto(s)
Lista de Verificación , Monitores de Ejercicio , Humanos , Ejercicio Físico , Motivación , Atención a la Salud
8.
J Am Chem Soc ; 146(2): 1257-1261, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38189272

RESUMEN

Dihydrogen complexation, a phenomenon with robust precedent in the transition metal series, is spectroscopically detected for a uranium(III) complex and thereby extended for the first time to the 5f series. The vacant coordination site and low valence of (C5H4SiMe3)3U prove to be key to the reversible formation of (C5H4SiMe3)3U-H2 (complex 1), and the paramagnetism of the f3 center facilitates the detection of complex 1 by NMR spectroscopy. Density functional theory calculations reveal that the delocalization of the 5f electron density from (C5H4SiMe3)3U onto the side-on dihydrogen ligand is crucial to complex formation, an unusual bonding situation for an actinide acid-base complex. The spectroscopic and computational results are compared to those reported for lanthanide metallocenes to yield insight into the nature of─and future possibilities for─f-element dihydrogen complexation.

9.
Int J Sports Physiol Perform ; 19(2): 207-211, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37995677

RESUMEN

PURPOSE: There are important methodological considerations for translating wearable-based gait-monitoring data to field settings. This study investigated different devices' sampling rates, signal lengths, and testing frequencies for athlete monitoring using dynamical systems variables. METHODS: Secondary analysis of previous wearables data (N = 10 runners) from a 5-week intensive training intervention investigated impacts of sampling rate (100-2000 Hz) and signal length (100-300 strides) on detection of gait changes caused by intensive training. Primary analysis of data from 13 separate runners during 1 week of field-based testing determined day-to-day stability of outcomes using single-session data and mean data from 2 sessions. Stride-interval long-range correlation coefficient α from detrended fluctuation analysis was the gait outcome variable. RESULTS: Stride-interval α reduced at 100- and 200- versus 300- to 2000-Hz sampling rates (mean difference: -.02 to -.08; P ≤ .045) and at 100- compared to 200- to 300-stride signal lengths (mean difference: -.05 to -.07; P < .010). Effects of intensive training were detected at 100, 200, and 400 to 2000 Hz (P ≤ .043) but not 300 Hz (P = .069). Within-athlete α variability was lower using 2-session mean versus single-session data (smallest detectable change: .13 and .22, respectively). CONCLUSIONS: Detecting altered gait following intensive training was possible using 200 to 300 strides and a 100-Hz sampling rate, although 100 and 200 Hz underestimated α compared to higher rates. Using 2-session mean data lowers smallest detectable change values by nearly half compared to single-session data. Coaches, runners, and researchers can use these findings to integrate wearable-device gait monitoring into practice using dynamic systems variables.


Asunto(s)
Carrera , Dispositivos Electrónicos Vestibles , Humanos , Marcha , Atletas , Fatiga , Fenómenos Biomecánicos
10.
Psychol Sport Exerc ; 71: 102581, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38061406

RESUMEN

Running is a popular form of physical activity yet discontinuation is common. Interventions targeting physical activity adoption have shown modest effects, often with little translation into long-term participation, which may limit the health benefits available to the wider community. This paper details the development of a new online running intervention (Just Run) aimed at improving continuation of running activity in new runners through a motivational and psychological lens, including aspects of design, content, refinement, and usability testing. A six-step intervention mapping process was used to develop a theory-based online intervention using a mix of research designs. Key stakeholders including runners, coaches and relevant experts in physical activity and behavior change provided valuable insight, feedback and refinement of the education to be delivered. The final Just Run intervention included ten modules delivered online over twelve weeks to promote ongoing running participation through videos, testimonials, and activities. Key themes identified through the literature and stakeholder engagement process related to goal setting, self-efficacy, intrinsic motivation, social support and overcoming barriers to running participation. Usability testing confirmed the quality and suitability of the education to the target population. Just Run has been developed with a range of stakeholders to address an area of unmet need in the adoption and promotion of running. Just Run is a robust online intervention that has been designed and pre-tested with positive feedback and unique insights from key stakeholders. Further investigation is required to support its implementation to the wider community.


Asunto(s)
Intervención basada en la Internet , Carrera , Motivación , Ejercicio Físico/psicología
11.
J Pharm Pract ; : 8971900231213938, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37933430

RESUMEN

Background: Increased patient utilization of cannabidiol (CBD) leads to potential drug interactions with various medications and questions posed to pharmacists. Objective: To quantify the knowledge gap of pharmacists on CBD and CBD-containing products and assess the degree a continuing pharmacy education (CPE) program alters pharmacist confidence and competency on CBD knowledge. Methods: A 1-h CPE activity was offered as a home study from May 9, 2022, through September 30, 2022. Subjects were practicing pharmacy preceptors in Alabama who completed the pre-survey and post-survey for inclusion in matched-pair analyses. The primary outcome measure was participant score improvement between the pre-post surveys. Secondary measures involved pre-post comparisons on self-rated Likert questions concerning participant confidence in counseling, answering drug information questions, and ensuring patient safety regarding CBD. Results: A total of 124 participants completed the course. After matched pairing, 64 and 56 individuals were included in the knowledge-based and confidence ranking analyses, respectively. Participant scoring improved on the knowledge-based questions between the pre-post surveys (50.0% vs 87.8%, P < .001). There was a significant confidence improvement of participants from baseline on counseling patients about prescription or over-the-counter CBD products, answering questions from other healthcare professionals about these products, and ensuring patient safety while using these products (Average 5-level Likert scale increases of 1.75, 1.73, 1.70, respectively; all P < .001). Conclusion: Implementation of a CPE program improved practicing pharmacists' knowledge on information about CBD, which lead to increased competency on counseling patients, answering drug information questions, and promoting patient safety.

12.
JAMA Netw Open ; 6(6): e2318478, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-37318806

RESUMEN

Importance: Low levels of physical activity during hospitalization are thought to contribute to a range of poor outcomes for patients. Using wearable activity trackers during hospitalization may help improve patient activity, sedentary behavior, and other outcomes. Objective: To evaluate the association of interventions that use wearable activity trackers during hospitalization with patient physical activity, sedentary behavior, clinical outcomes, and hospital efficiency outcomes. Data Sources: OVID MEDLINE, CINAHL, Embase, EmCare, PEDro, SportDiscuss, and Scopus databases were searched from inception to March 2022. The Cochrane Central Register for Controlled trials, ClinicalTrials.gov, and World Health Organization Clinical Trials Registry were also searched for registered protocols. No language restrictions were imposed. Study Selection: Randomized clinical trials and nonrandomized clinical trials of interventions that used wearable activity trackers to increase physical activity or reduce sedentary behavior in adults (aged 18 years or older) who were hospitalized were included. Data Extraction and Synthesis: Study selection, data extraction, and critical appraisal were conducted in duplicate. Data were pooled for meta-analysis using random-effects models. The Preferred Reporting Items for Systematic Reviews and Meta-analyses guideline was followed. Main Outcomes and Measures: The primary outcomes were objectively measured physical activity or sedentary behavior. Secondary outcomes included clinical outcomes (eg, physical function, pain, mental health), and hospital efficiency outcomes (eg, length of stay, readmission). Results: Fifteen studies with a total of 1911 participants were included, representing various surgical cohorts (4 studies), stroke rehabilitation (3 studies), orthopedic rehabilitation (3 studies), mixed rehabilitation (3 studies), and mixed medical (2 studies). All studies were included in meta-analyses. There was a significant association between wearable activity tracker interventions with higher overall physical activity (standardized mean difference, 0.35; 95% CI, 0.15 to 0.54; I2 = 72%; P < .002) and less sedentary behavior (mean difference, -35.46 min/d; 95% CI, -57.43 to -13.48 min/d; I2 = 0; P = .002), and a significant association between wearable activity tracker interventions with improvements in physical function (standardized mean difference, 0.27; 95% CI, 0.08 to 0.46; I2 = 0; P = .006) compared with usual care. There was no significant association between wearable activity tracker interventions with pain, mental health, length of stay, or readmission risk. Conclusions and Relevance: In this systematic review and meta-analysis, interventions that used wearable activity trackers with patients who are hospitalized were associated with higher physical activity levels, less sedentary behavior, and better physical functioning compared with usual care.


Asunto(s)
Ejercicio Físico , Monitores de Ejercicio , Adulto , Humanos , Ejercicio Físico/psicología , Hospitalización , Hospitales , Dolor
13.
Semin Arthritis Rheum ; 61: 152210, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37156170

RESUMEN

OBJECTIVES: Foot and ankle involvement is common in rheumatic and musculoskeletal diseases, yet high-quality evidence assessing the effectiveness of treatments for these disorders is lacking. The Outcome Measures in Rheumatology (OMERACT) Foot and Ankle Working Group is developing a core outcome set for use in clinical trials and longitudinal observational studies in this area. METHODS: A scoping review was performed to identify outcome domains in the existing literature. Clinical trials and observational studies comparing pharmacological, conservative or surgical interventions involving adult participants with any foot or ankle disorder in the following rheumatic and musculoskeletal diseases (RMDs) were eligible for inclusion: rheumatoid arthritis (RA), osteoarthritis (OA), spondyloarthropathies, crystal arthropathies and connective tissue diseases. Outcome domains were categorised according to the OMERACT Filter 2.1. RESULTS: Outcome domains were extracted from 150 eligible studies. Most studies included participants with foot/ankle OA (63% of studies) or foot/ankle involvement in RA (29% of studies). Foot/ankle pain was the outcome domain most commonly measured (78% of studies), being the most frequently specified outcome domain across all RMDs. There was considerable heterogeneity in the other outcome domains measured, across core areas of manifestations (signs, symptoms, biomarkers), life impact, and societal/resource use. The group's progress to date, including findings from the scoping review, was presented and discussed during a virtual OMERACT Special Interest Group (SIG) in October 2022. During this meeting, feedback was sought amongst delegates regarding the scope of the core outcome set, and feedback was received on the next steps of the project, including focus group and Delphi methods. CONCLUSION: Findings from the scoping review and feedback from the SIG will contribute to the development of a core outcome set for foot and ankle disorders in RMDs. The next steps are to determine which outcome domains are important to patients, followed by a Delphi exercise with key stakeholders to prioritise outcome domains.


Asunto(s)
Artritis Reumatoide , Osteoartritis , Reumatología , Humanos , Tobillo , Opinión Pública , Evaluación de Resultado en la Atención de Salud
14.
Sensors (Basel) ; 23(7)2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-37050665

RESUMEN

Three-dimensional video services delivered through wireless communication channels have to deal with numerous challenges due to the limitations of both the transmission channel's bandwidth and receiving devices. Adverse channel conditions, delays, or jitters can result in bit errors and packet losses, which can alter the appearance of stereoscopic 3D (S3D) video. Due to the perception of dissimilar patterns by the two human eyes, they can not be fused into a stable composite pattern in the brain and hence try to dominate by suppressing each other. Thus, a psychovisual sensation that is called binocular rivalry occurs. As a result, undetectable changes causing irritating flickering effects are seen, leading to visual discomforts such as eye strain, headache, nausea, and weariness. This study addresses the observer's quality of experience (QoE) by analyzing the binocular rivalry impact on the macroblock (MB) losses in a frame and its error propagation due to predictive frame encoding in stereoscopic video transmission systems. To simulate the processing of experimental videos, the Joint Test Model (JM) reference software has been used as it is recommended by the International Telecommunication Union (ITU). Existing error concealing techniques were then applied to the contiguous lost MBs for a variety of transmission impairments. In order to validate the authenticity of the simulated packet loss environment, several objective evaluations were carried out. Standard numbers of subjects were then engaged in the subjective testing of common 3D video sequences. The results were then statistically examined using a standard Student's t-test, allowing the impact of binocular rivalry to be compared to that of a non-rivalry error condition. The major goal is to assure error-free video communication by minimizing the negative impacts of binocular rivalry and boosting the ability to efficiently integrate 3D video material to improve viewers' overall QoE.

15.
J Appl Psychol ; 108(9): 1486-1514, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37036689

RESUMEN

Although human capital resources (HCR) can be important for organizational performance, researchers have defined and measured HCR in various ways. Consequently, it is unclear whether existing measures provide valid inferences about HCR or their relations with other constructs. We conducted this three-study research to address these issues. In Study 1, we reviewed HCR definitions (k = 84) and found that most definitions focus on collective knowledge, skills, and abilities. Recent definitions also tend to include other characteristics (e.g., personality). In Study 2, a content analysis of HCR measures (k = 127) revealed that only 23.6% of the measures focused solely on HCR and they tended to assess only one or two dimensions of the construct (i.e., were deficient). Many measures (46.5%) assessed both HCR and other constructs (i.e., were partially contaminated), and other measures (29.9%) assessed only non-HCR constructs (i.e., were fully contaminated). In Study 3 (k = 94), we found that HCR measures that were less deficient demonstrated stronger criterion-related validity for predicting unit and firm performance. Interestingly, partially contaminated measures were somewhat more predictive than uncontaminated measures (ρ = .35 vs. .25, respectively), mainly because they assessed both HCR and other constructs that are related to performance. Both types of measures demonstrated stronger validity than fully contaminated measures. Overall, findings suggest that extant HCR measures often are deficient and/or contaminated. We discuss implications, as well as offer guidance for measuring HCR in future research. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Asunto(s)
Eficiencia Organizacional , Recursos Humanos , Humanos , Personalidad
16.
Chem Sci ; 14(4): 861-868, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36755711

RESUMEN

Reaction of the potassium pentamethylcyclopentadienyl iridate tris-hydride K[IrCp*H3] with UCl4 and ThCl4(DME)2 led to the complete replacement of the halide ligands to generate multimetallic complexes U{(µ-H)3IrCp*}4 (1) and Th{[(µ-H2)(H)IrCp*]2[(µ-H)3IrCp*]2} (2), respectively. These analogues feature a significant discrepancy in hydride bonding modes; 1 contains twelve bridging hydrides while 2 contains ten bridging hydrides and two terminal, Ir-bound hydrides. Use of a U(iii) starting material, UI3(1,4-dioxane)1.5, resulted in the octanuclear complex {U[(µ2-H3)IrCp*]2[(µ3-H2)IrCp*]}2 (3). Computational studies indicate significant bonding character between U/Th and Ir in 1 and 2, with f-orbital involvement in the singly-occupied molecular orbitals of the uranium species 1. In addition, these studies attribute the variation in hydride bonding between 1 and 2 to differences in dispersion effects.

17.
Trials ; 24(1): 65, 2023 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-36709309

RESUMEN

BACKGROUND: Foot and ankle involvement is common in rheumatic and musculoskeletal diseases (RMDs). High-quality evidence is lacking to determine the effectiveness of treatments for these disorders. Heterogeneity in the outcomes used across clinical trials and observational studies hinders the ability to compare findings, and some outcomes are not always meaningful to patients and end-users. The Core set of Outcome Measures for FOot and ankle disorders in RheumaTic and musculoskeletal diseases (COMFORT) study aims to develop a core outcome set (COS) for use in all trials of interventions for foot and ankle disorders in RMDs. This protocol addresses core outcome domains (what to measure) only. Future work will focus on core outcome measurement instruments (how to measure). METHODS: COMFORT: Core Domain Set is a mixed-methods study involving the following: (i) identification of important outcome domains through literature reviews, qualitative interviews and focus groups with patients and (ii) prioritisation of domains through an online, modified Delphi consensus study and subsequent consensus meeting with representation from all stakeholder groups. Findings will be disseminated widely to enhance uptake. CONCLUSIONS: This protocol details the development process and methodology to identify and prioritise domains for a COS in the novel area of foot and ankle disorders in RMDs. Future use of this standardised set of outcome domains, developed with all key stakeholders, will help address issues with outcome variability. This will facilitate comparing and combining study findings, thus improving the evidence base for treatments of these conditions. Future work will identify suitable outcome measurement instruments for each of the core domains. TRIAL REGISTRATION: This study is registered with the Core Outcome Measures in Effectiveness Trials (COMET) database, as of June 2022: https://www.comet-initiative.org/Studies/Details/2081.


Asunto(s)
Enfermedades Musculoesqueléticas , Reumatología , Humanos , Resultado del Tratamiento , Tobillo , Proyectos de Investigación , Técnica Delphi , Evaluación de Resultado en la Atención de Salud , Enfermedades Musculoesqueléticas/diagnóstico , Enfermedades Musculoesqueléticas/terapia
18.
Arthritis Care Res (Hoboken) ; 75(5): 1113-1122, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-35593411

RESUMEN

OBJECTIVE: To compare magnetic resonance imaging (MRI)-detected structural abnormalities in patients with symptomatic midfoot osteoarthritis (OA), patients with persistent midfoot pain, and asymptomatic controls, and to explore the association between MRI features, pain, and foot-related disability. METHODS: One hundred seven adults consisting of 50 patients with symptomatic and radiographically confirmed midfoot OA, 22 adults with persistent midfoot pain but absence of radiographic OA, and 35 asymptomatic adults underwent 3T MRI of the midfoot and clinical assessment. MRIs were read for the presence and severity of abnormalities (bone marrow lesions [BMLs], subchondral cysts, osteophytes, joint space narrowing [JSN], effusion-synovitis, tenosynovitis, and enthesopathy) using the Foot Osteoarthritis MRI Score. Pain and foot-related disability were assessed with the Manchester Foot Pain and Disability Index. RESULTS: The severity sum score of BMLs in the midfoot was greater in patients with midfoot pain and no signs of OA on radiography compared to controls (P = 0.007), with a pattern of involvement in the cuneiform-metatarsal joints similar to that in patients with midfoot OA. In univariable models, BMLs (ρ = 0.307), JSN (ρ = 0.423), and subchondral cysts (ρ = 0.302) were positively associated with pain (P < 0.01). In multivariable models, MRI abnormalities were not associated with pain and disability when adjusted for covariates. CONCLUSION: In individuals with persistent midfoot pain but no signs of OA on radiography, MRI findings suggested an underrecognized prevalence of OA, particularly in the second and third cuneiform-metatarsal joints, where BML patterns were consistent with previously recognized sites of elevated mechanical loading. Joint abnormalities were not strongly associated with pain or foot-related disability.


Asunto(s)
Quistes Óseos , Osteoartritis de la Rodilla , Osteoartritis , Adulto , Humanos , Estudios Transversales , Médula Ósea , Osteoartritis/diagnóstico , Imagen por Resonancia Magnética , Dolor/patología , Quistes Óseos/patología , Osteoartritis de la Rodilla/patología
19.
Med Sci Sports Exerc ; 55(3): 581-589, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36251400

RESUMEN

BACKGROUND: High-impact loads have been linked with running injuries. Fatigue has been proposed to increase impact loads, but this relationship has not been rigorously examined, including the associated role of muscle strength, power, and endurance. PURPOSE: This study aimed to investigate the effect of fatigue on impact loading in runners and the role of muscle function in mediating changes in impact loading with fatigue. METHODS: Twenty-eight trained endurance runners performed a fixed-intensity time to exhaustion test at 85% of V̇O 2max . Tibial accelerations were measured using leg-mounted inertial measurement units and sampled every minute until volitional exhaustion. Tests of lower limb muscle strength, power, and endurance included maximal isometric strength (soleus, knee extensors, and knee flexors), single leg hop for distance, and the one leg rise test. Changes in peak tibial acceleration (PTA, g ) were compared between time points throughout the run (0%, 25%, 50%, 75%, and 100%). Associations between the change in PTA and lower limb muscle function tests were assessed (Spearman's rho [ rs ]). RESULTS: PTA increased over the duration of the fatiguing run. Compared with baseline (0%) (mean ± SD, 9.1 g ± 1.6 g ), there was a significant increase at 75% (9.9 g ± 1.7 g , P = 0.001) and 100% (10.1 g ± 1.8 g , P < 0.001), with no change at 25% (9.6 g ± 1.6 g , P = 0.142) or 50% (9.7 g ± 1.7 g , P = 0.053). Relationships between change in PTA and muscle function tests were weak and not statistically significant ( rs = -0.153 to 0.142, all P > 0.05). CONCLUSIONS: Peak axial tibial acceleration increased throughout a fixed-intensity run to exhaustion. The change in PTA was not related to performance in lower limb muscle function tests.


Asunto(s)
Pierna , Carrera , Humanos , Pierna/fisiología , Extremidad Inferior , Carrera/fisiología , Músculo Esquelético/fisiología , Fatiga , Fuerza Muscular , Aceleración , Fatiga Muscular/fisiología , Resistencia Física/fisiología
20.
J Orthop Res ; 41(6): 1240-1247, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36200414

RESUMEN

The aim of this study was to determine the effect of surgical change to the acetabular offset and femoral offset on the abductor muscle and hip contact forces after primary total hip arthroplasty (THA) using computational methods. Thirty-five patients undergoing primary THA were recruited. Patients underwent a computed tomography scan of their pelvis and hip, and underwent gait analysis pre- and 6-months postoperatively. Surgically induced changes in acetabular and femoral offset were used to inform a musculoskeletal model to estimated abductor muscle and hip joint contact forces. Two experiments were performed: (1) influence of changes in hip geometry on hip biomechanics with preoperative kinematics; and (2) influence of changes in hip geometry on hip biomechanics with postoperative kinematics. Superior and medial placement of the hip centre of rotation during THA was most influential in reducing hip contact forces, predicting 63% of the variance (p < 0.001). When comparing the preoperative geometry and kinematics model, with postoperative geometry and kinematics, hip contact forces increased after surgery (0.68 BW, p = 0.001). Increasing the abductor lever arm reduced abductor muscle force by 28% (p < 0.001) and resultant hip contact force by 17% (0.6 BW, p = 0.003), with both preoperative and postoperative kinematics. Failure to increase abductor lever arm increased resultant hip contact force 11% (0.33 BW, p < 0.001). In conclusion, increasing the abductor lever arm provides a substantial biomechanical benefit to reduce hip abductor and resultant hip joint contact forces. The magnitude of this effect is equivalent to the average increase in hip contact force seen with improved gait from pre-to post-surgery.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Humanos , Artroplastia de Reemplazo de Cadera/métodos , Fenómenos Biomecánicos , Articulación de la Cadera/diagnóstico por imagen , Articulación de la Cadera/cirugía , Articulación de la Cadera/fisiología , Acetábulo/cirugía , Músculo Esquelético/fisiología
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