72 research outputs found
The Dutch language short Anterior Cruciate LigamentâReturn to Sport after Injury scale has good to excellent construct validity, internal consistency, and test-retest reliability when assessing athletes undergoing rehabilitation after ACL injury or ACL reconstruction
Objectives: To examine the validity and reliability of the Dutch language short Anterior Cruciate LigamentâReturn to Sport after Injury scale (short ACL-RSI-NL) in recreational athletes undergoing rehabilitation after ACL injury or ACL reconstruction (ACLR). Methods: The original 12-item version of the ACL-RSI had been translated into Dutch. Short ACL-RSI-NL items were derived from this 12-item Dutch version. Content validity was evaluated by a team consisting of eight ACL experts and eight athletes. A cohort of 115 athletes with ACL injury or after ACLR completed the short ACL-RSI-NL and related questionnaires at various time points during their rehabilitation. Construct validity (hypothesis testing using Spearman correlations), internal consistency (Cronbach's alpha), floor and ceiling effects (percentage of athletes having the lowest or highest score possible), and structural validity (exploratory factor analysis) were evaluated in the entire ACL athlete group. Test-retest reliability (using intra-class correlation, ICC; standard error of measurement, SEM; smallest detectable change, SDC, at both group and individual levels) was investigated in a subgroup of athletes with a stable outcome on psychological readiness within a two-week interval (n â= â27). Results: The short ACL-RSI-NL demonstrated good construct validity (83% of hypotheses confirmed). Internal consistency was excellent (Cronbach's alpha 0.84), and there were no floor and ceiling effects (â€13.9% lowest or highest score). Test-retest reliability was good (ICC 0.89 with 95% CI 0.77â0.95, SEM 6.93, SDC individual level 19.2, SDC group level 3.7). Exploratory factor analysis confirmed the presence of a single underlying factor (accounting for 56.4% of the total variance of the score). Conclusion: The short ACL-RSI-NL exhibited good to excellent construct validity, internal consistency, and test-retest reliability. An averaged score ranging from 0 to 100 can be used to measure psychological readiness to return to sport. The short ACL-RSI-NL has potential for use in day-to-day practice to assess the psychological readiness of recreational athletes to return to sport after ACL injury or ACLR during their rehabilitation process. Level of evidence: Level II.</p
Debris cover and surface melt at a temperate maritime alpine glacier: Franz Josef Glacier, New Zealand
Melt rates on glaciers are strongly influenced by the presence of supraglacial debris, which can either enhance or reduce ablation relative to bare ice. Most recently, Franz Josef Glacier has entered into a phase of strong retreat and downwasting, with the increasing emergence of debris on the surface in the ablation zone. Previously at Franz Josef Glacier, melt has only been measured on bare ice. During February 2012, a network of 11 ablation stakes was drilled into locations of varying supraglacial debris thickness on the lower glacier. Mean ablation rates over 9 days varied over the range 1.2â10.1 cm dâ1, and were closely related to debris thickness. Concomitant observations of air temperature allowed the application of a degree-day approach to the calculation of melt rates, with air temperature providing a strong indicator of melt. Degree-day factors (d f) varied over the range 1.1â8.1 mm dâ1 °Câ1 (mean of 4.4 mm dâ1 °Câ1), comparable with rates reported in other studies. Mapping of the current debris cover revealed 0.7 km2 of the 4.9 km2 ablation zone surface was debris-covered, with thicknesses ranging 1â50 cm. Based on measured debris thicknesses and d f, ablation on debris-covered areas of the glacier is reduced by a total of 41% which equates to a 6% reduction in melt overall across the entire ablation zone. This study highlights the usefulness of a short-term survey to gather representative ablation data, consistent with numerous overseas ablation studies on debris-covered glaciers
On the role of soil water retention characteristic on aerobic microbial respiration
Soil water status is one of the
most important environmental factors that control microbial activity and rate of soil
organic matter (SOM) decomposition. Its effect can be partitioned into effect of water
energy status (water potential) on cellular activity, effect of water volume on cellular
motility, and aqueous diffusion of substrate and nutrients, as well as the effect of air
content and gas-diffusion pathways on concentration of dissolved oxygen. However,
moisture functions widely used in SOM decomposition models are often based on empirical
functions rather than robust physical foundations that account for these disparate
impacts of soil water. The contributions of soil water content and water potential vary
from soil to soil according to the soil water characteristic (SWC), which in turn is
strongly dependent on soil texture and structure. The overall goal of this study is to
introduce a physically based modeling framework of aerobic microbial respiration that
incorporates the role of SWC under arbitrary soil moisture status. The model was tested
by comparing it with published datasets of SOM decomposition under laboratory conditions.</p
Remote Electrical Stimulation by Means of Implanted Rectifiers
Miniaturization of active implantable medical devices is currently compromised by the available means for electrically powering them. Most common energy supply techniques for implants â batteries and inductive couplers â comprise bulky parts which, in most cases, are significantly larger than the circuitry they feed. Here, for overcoming such miniaturization bottleneck in the case of implants for electrical stimulation, it is proposed to make those implants act as rectifiers of high frequency bursts supplied by remote electrodes. In this way, low frequency currents will be generated locally around the implant and these low frequency currents will perform stimulation of excitable tissues whereas the high frequency currents will cause only innocuous heating. The present study numerically demonstrates that low frequency currents capable of stimulation can be produced by a miniature device behaving as a diode when high frequency currents, neither capable of thermal damage nor of stimulation, flow through the tissue where the device is implanted. Moreover, experimental evidence is provided by an in vivo proof of concept model consisting of an anesthetized earthworm in which a commercial diode was implanted. With currently available microelectronic techniques, very thin stimulation capsules (diameter <500 ”m) deliverable by injection are easily conceivable
Stearoyl-CoA desaturase-1 impairs the reparative properties of macrophages and microglia in the brain
Failure of remyelination underlies the progressive nature of demyelinating diseases such as multiple sclerosis. Macrophages and microglia are crucially involved in the formation and repair of demyelinated lesions. Here we show that myelin uptake temporarily skewed these phagocytes toward a disease-resolving phenotype, while sustained intracellular accumulation of myelin induced a lesion-promoting phenotype. This phenotypic shift was controlled by stearoyl-CoA desaturase-1 (SCD1), an enzyme responsible for the desaturation of saturated fatty acids. Monounsaturated fatty acids generated by SCD1 reduced the surface abundance of the cholesterol efflux transporter ABCA1, which in turn promoted lipid accumulation and induced an inflammatory phagocyte phenotype. Pharmacological inhibition or phagocyte-specific deficiency of Scd1 accelerated remyelination ex vivo and in vivo. These findings identify SCD1 as a novel therapeutic target to promote remyelination
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Characterizing Long COVID in Children and Adolescents
ImportanceMost research to understand postacute sequelae of SARS-CoV-2 infection (PASC), or long COVID, has focused on adults, with less known about this complex condition in children. Research is needed to characterize pediatric PASC to enable studies of underlying mechanisms that will guide future treatment.ObjectiveTo identify the most common prolonged symptoms experienced by children (aged 6 to 17 years) after SARS-CoV-2 infection, how these symptoms differ by age (school-age [6-11 years] vs adolescents [12-17 years]), how they cluster into distinct phenotypes, and what symptoms in combination could be used as an empirically derived index to assist researchers to study the likely presence of PASC.Design, setting, and participantsMulticenter longitudinal observational cohort study with participants recruited from more than 60 US health care and community settings between March 2022 and December 2023, including school-age children and adolescents with and without SARS-CoV-2 infection history.ExposureSARS-CoV-2 infection.Main outcomes and measuresPASC and 89 prolonged symptoms across 9 symptom domains.ResultsA total of 898 school-age children (751 with previous SARS-CoV-2 infection [referred to as infected] and 147 without [referred to as uninfected]; mean age, 8.6 years; 49% female; 11% were Black or African American, 34% were Hispanic, Latino, or Spanish, and 60% were White) and 4469 adolescents (3109 infected and 1360 uninfected; mean age, 14.8 years; 48% female; 13% were Black or African American, 21% were Hispanic, Latino, or Spanish, and 73% were White) were included. Median time between first infection and symptom survey was 506 days for school-age children and 556 days for adolescents. In models adjusted for sex and race and ethnicity, 14 symptoms in both school-age children and adolescents were more common in those with SARS-CoV-2 infection history compared with those without infection history, with 4 additional symptoms in school-age children only and 3 in adolescents only. These symptoms affected almost every organ system. Combinations of symptoms most associated with infection history were identified to form a PASC research index for each age group; these indices correlated with poorer overall health and quality of life. The index emphasizes neurocognitive, pain, and gastrointestinal symptoms in school-age children but change or loss in smell or taste, pain, and fatigue/malaise-related symptoms in adolescents. Clustering analyses identified 4 PASC symptom phenotypes in school-age children and 3 in adolescents.Conclusions and relevanceThis study developed research indices for characterizing PASC in children and adolescents. Symptom patterns were similar but distinguishable between the 2 groups, highlighting the importance of characterizing PASC separately for these age ranges
Agroforesterie et services écosystémiques en zone tropicale
Respectueux de lâenvironnement et garantissant une sĂ©curitĂ© alimentaire soutenue par la diversification des productions et des revenus quâils procurent, les systĂšmes agroforestiers apparaissent comme un modĂšle prometteur dâagriculture durable dans les pays du Sud les plus vulnĂ©rables aux changements globaux. Cependant, ces systĂšmes agroforestiers ne peuvent ĂȘtre optimisĂ©s quâĂ condition de mieux comprendre et de mieux maĂźtriser les facteurs de leurs productions. Lâouvrage prĂ©sente un ensemble de connaissances rĂ©centes sur les mĂ©canismes biophysiques et socio-Ă©conomiques qui sous-tendent le fonctionnement et la dynamique des systĂšmes agroforestiers. Il concerne, dâune part les systĂšmes agroforestiers Ă base de cultures pĂ©rennes, telles que cacaoyers et cafĂ©iers, de rĂ©gions tropicales humides en AmĂ©rique du Sud, en Afrique de lâEst et du Centre, dâautre part les parcs arborĂ©s et arbustifs Ă base de cultures vivriĂšres, principalement de cĂ©rĂ©ales, de la rĂ©gion semi-aride subsaharienne dâAfrique de lâOuest. Il synthĂ©tise les derniĂšres avancĂ©es acquises grĂące Ă plusieurs projets associant le Cirad, lâIRD et leurs partenaires du Sud qui ont Ă©tĂ© conduits entre 2012 et 2016 dans ces rĂ©gions. Lâensemble de ces projets sâarticulent autour des dynamiques des systĂšmes agroforestiers et des compromis entre les services de production et les autres services socio-Ă©cosystĂ©miques que ces systĂšmes fournissent
Three traditional and three new childhood anxiety questionnaires: their reliability and validity in a normal adolescent sample.
The current study examined the psychometrics of three traditional [i.e., the trait anxiety version of the State-Trait Anxiety Inventory for Children (STAIC), the Revised Children's Manifest Anxiety Scale (RCMAS), and the Fear Survey Schedule for Children - Revised (FSSC-R)] and three new childhood anxiety scales [the Multidimensional Anxiety Scale for Children (MASC), the Screen for Child Anxiety Related Emotional Disorders (SCARED), and the Spence Children's Anxiety Scale (SCAS)] in a large sample of normal adolescents (N=521). Childhood anxiety scales were generally found to be reliable in terms of internal consistency. Furthermore, evidence was obtained for the convergent and divergent validity of the various anxiety questionnaires. That is, anxiety questionnaire scores were found to be substantially intercorrelated. Particularly strong associations were found between total scores of the STAIC and the RCMAS, total scores of the SCARED and the SCAS, and between subscales that intend to measure specific categories of anxiety symptoms. Childhood anxiety questionnaires were substantially connected to an index of depression, although correlations among anxiety questionnaires were generally higher than those between anxiety scales and a measure of depression
Anxiety and depression as correlates of self-reported behavioural inhibition in normal adolescents.
In a previous study, Muris, Merckelbach, Wessel, and Van de Ven [Psychopathological correlates of self-reported behavioural inhibition in normal children. Behav. Res. Ther. 37 (1999) 575-584] found that children who defined themselves as high on behavioural inhibition displayed elevated levels of psychopathological symptoms compared to children who defined themselves as low or middle on behavioural inhibition. The present study further examined the relationship between self-reported behavioural inhibition and anxiety disorders and depression symptoms in a large sample of adolescents aged 12-18 years (N=968). Adolescents completed a measure of behavioural inhibition and questionnaires of anxiety and depression. Results indicated that adolescents who classified themselves as high on behavioural inhibition had higher scores of anxiety and depression than adolescents who classified themselves as low or middle on behavioural inhibition. Structural equations modelling was employed to test hypothetical models on the role of behavioural inhibition in childhood anxiety and depression. It was found that a pathway in which behavioural inhibition results in anxiety, which in turn leads to depression, provided the best fit for the data
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