214 research outputs found
Measuring the Effects of Workloss on Productivity With Team Production
Using data from a survey of 800 managers in 12 industries, we find empirical support for the hypothesis that the cost associated with missed work varies across jobs according to the ease with which a manager can find a perfect replacement for the absent worker, the extent to which the worker functions as part of a team, and the time sensitivity of the worker's output. We then estimate wage multipliers' for 35 different jobs, where the multiplier is defined as the cost to the firm of an absence as a proportion (often greater than one) of the absent worker's daily wage. The median multiplier is 1.28, which supports the view that the cost to the firm of missed work is often greater than the wage.
Retrograde procedural memory is impaired in people with Parkinson’s disease with freezing of gait
BackgroundFreezing of gait (FOG), is associated with impairment of different cognitive functions. Previous studies hypothesized that FOG may be due to a loss of automaticity.Research questionTo explore whether FOG is associated with impairment in cognitive functions, focusing on retrograde procedural memory, the memory responsible for the automatic, implicit stored procedures that have been acquired in earlier life stages.MethodsIn this cross-sectional, case–control study, 288 people with typical Parkinson’s disease (PD) from the Luxembourg Parkinson’s Study were assigned to Freezers (FOG+) and non-Freezers (FOG−) based on the MDS-UPDRS 2.13 (self-reported FOG episodes) and 3.11 (FOG evaluated by clinicians during gait assessment). Both groups were matched on age, sex and disease duration. Global cognition (MoCA), retrograde procedural memory and visuo-constructive abilities (CUPRO), psychomotor speed and mental flexibility (TMT) were assessed. Furthermore, we repeated our analyses by additionally controlling for depression (BDI-I).ResultsBesides lower global cognition (MoCA; p = 0.007) and mental flexibility (TMT-B and Delta-TMT; p < 0.001), FOG+ showed a lower performance in retrograde procedural memory (CUPRO-IS1; p < 0.001) compared to FOG−. After controlling additionally for depression, our main outcome variable CUPRO-IS1 remained significantly lower in FOG+ (p = 0.010).ConclusionOur findings demonstrated that besides lower global cognition and mental flexibility scores, FOG+ showed lower performance in retrograde procedural memory compared to matched FOG-control patients, even when accounting for factors such as age, sex, disease duration or depression.SignificanceIn the context of limited treatment options, especially for non-invasive therapeutic approaches, these insights on procedural memory and FOG may lead to new hypotheses on FOG etiology and consequently the development of new treatment options
PRELIMINARY RESULTS ON THE COGNITIVE PROFILE IN PRODROMAL PARKINSON’S DISEASE – A PROSPECTIVE STUDY
Genetically stratified Parkinson’s disease with freezing of gait is related to specific pattern of cognitive impairment and non-motor dominant endophenotype
BackgroundFreezing of gait (FOG) is an important milestone in the individual disease trajectory of people with Parkinson’s disease (PD). Based on the cognitive model of FOG etiology, the mechanism behind FOG implies higher executive dysfunction in PDFOG+. To test this model, we investigated the FOG-related phenotype and cognitive subdomains in idiopathic PD (iPD) patients without genetic variants linked to PD from the Luxembourg Parkinson’s study.MethodsA cross-sectional analysis comparing iPDFOG+ (n = 118) and iPDFOG− (n = 378) individuals was performed, followed by the application of logistic regression models. Consequently, regression models were fitted for a subset of iPDFOG+ (n = 35) vs. iPDFOG− (n = 126), utilizing a detailed neuropsychological battery to assess the association between FOG and cognitive subdomains. Both regression models were adjusted for sociodemographic confounders and disease severity.ResultsiPDFOG+ individuals presented with more motor complications (MDS-UPDRS IV) compared to iPDFOG- individuals. Moreover, iPDFOG+ individuals exhibited a higher non-motor burden, including a higher frequency of hallucinations, higher MDS-UPDRS I scores, and more pronounced autonomic dysfunction as measured by the SCOPA-AUT. In addition, iPDFOG+ individuals showed lower sleep quality along with lower quality of life (measured by PDSS and PDQ-39, respectively). The cognitive subdomain analysis in iPDFOG+ vs. iPDFOG− indicated lower scores in Benton’s Judgment of Line Orientation test and CERAD word recognition, reflecting higher impairment in visuospatial, executive function, and memory encoding.ConclusionWe determined a significant association between FOG and a clinical endophenotype of PD with higher non-motor burden. While our results supported the cognitive model of FOG, our findings point to a more widespread cortical impairment across cognitive subdomains beyond the executive domain in PDFOG+ with additional higher impairment in visuospatial function and memory encoding
Multilingual Validation of the First French Version of Munich Dysphagia Test-Parkinson's Disease (MDT-PD) in the Luxembourg Parkinson's Study
The Munich Dysphagia Test for Parkinson's disease (MDT-PD) was initially developed and validated in the German population as a highly sensitive and specific self-reported screening questionnaire to detect early oropharyngeal symptoms and aspiration risk in patients with idiopathic Parkinson's disease (iPD). In order to make this tool accessible for prevention in the French speaking populations worldwide, we performed the first French translation and provide a linguistic and psychometric validation in the unique multilingual environment of the Luxembourg Parkinson's Study
Retrograde procedural memory is impaired in people with Parkinson’s disease with freezing of gait
peer reviewedFreezing of gait (FOG), is associated with impairment of different cognitive functions. Previous studies hypothesized that FOG may be due to a loss of automaticity. Research question: To explore whether FOG is associated with impairment in cognitive functions, focusing on retrograde procedural memory, the memory responsible for the automatic, implicit stored procedures that have been acquired in earlier life stages. Methods: In this cross-sectional, case–control study, 288 people with typical Parkinson’s disease (PD) from the Luxembourg Parkinson’s Study were assigned to Freezers (FOG+) and non-Freezers (FOG−) based on the MDS-UPDRS 2.13 (self-reported FOG episodes) and 3.11 (FOG evaluated by clinicians during gait assessment). Both groups were matched on age, sex and disease duration. Global cognition (MoCA), retrograde procedural memory and visuo-constructive abilities (CUPRO), psychomotor speed and mental flexibility (TMT) were assessed. Furthermore, we repeated our analyses by additionally controlling for depression (BDI-I). Results: Besides lower global cognition (MoCA; p = 0.007) and mental flexibility (TMT-B and Delta-TMT; p < 0.001), FOG+ showed a lower performance in retrograde procedural memory (CUPRO-IS1; p < 0.001) compared to FOG−. After controlling additionally for depression, our main outcome variable CUPRO-IS1 remained significantly lower in FOG+ (p = 0.010). Conclusion: Our findings demonstrated that besides lower global cognition and mental flexibility scores, FOG+ showed lower performance in retrograde procedural memory compared to matched FOG-control patients, even when accounting for factors such as age, sex, disease duration or depression. Significance: In the context of limited treatment options, especially for non-invasive therapeutic approaches, these insights on procedural memory and FOG may lead to new hypotheses on FOG etiology and consequently the development of new treatment options.3. Good health and well-bein
Quantifying activities of daily living impairment in Parkinson’s disease using the Functional Activities Questionnaire
Objective Cognitive-driven activity of daily living (ADL) impairment in Parkinson’s disease (PD) is increasingly discussed
as prodromal marker for dementia. Diagnostic properties of assessments for this specifc ADL impairment are sparsely
investigated in PD. The ability of the Functional Activities Questionnaire (FAQ) for diferentiating between PD patients with
normal cognition and with mild cognitive impairment (PD-MCI), according to informant and self-reports, was examined.
Global cognitive function in groups with and without mild ADL impairment was compared according to diferent cut-ofs.
Methods Multicenter data of 589 patients of an international cohort (CENTRE-PD) were analyzed. Analyses were run separately for informant-rated and self-rated FAQ. Receiver operating characteristic (ROC) analysis was conducted to defne the
optimal FAQ cut-of for PD-MCI (≥1), and groups were additionally split according to reported FAQ cut-ofs for PD-MCI
in the literature (≥3,≥5). Binary logistic regressions examined the efect of the Montreal Cognitive Assessment (MoCA)
score in PD patients with and without mild ADL impairment.
Results Two hundred and twenty-fve (38.2%) patients were classifed as PD-MCI. For all three cut-of values, sensitivity
was moderate to low (0.54) with a tendency of higher values for self-reported
defcits. For the self-report, the cut-of≥3 showed a signifcant efect of the MoCA (B= −0.31, p=0.003), where FAQ≥3
patients had worse cognition. No efect for group diferences based on informant ratings was detected.
Conclusion Our data argue that self-reported ADL impairments assessed by the FAQ show a relation to the severity of
cognitive impairment in PD
Cognition and Other Non-Motor Symptoms in an At-Risk Cohort for Parkinson’s Disease Defined by REM-Sleep Behavior Disorder and Hyposmia
peer reviewedBackground: REM-sleep behavior disorder (RBD) and other non-motor symptoms such as hyposmia were proposed by the Movement Disorder Society as research criteria for prodromal Parkinson’s disease (P-PD). Global cognitive deficit was later added. Objective: To compare non-motor symptoms, focusing on cognition, between a P-PD group and a matched control group. Methods: In this cross-sectional, case-control study, in a first set of analyses, we performed extensive cognitive testing on people with (n = 76) and a control group without (n = 195) probable RBD and hyposmia. Furthermore, we assessed motor and non-motor symptoms related to Parkinson’s Disease (PD). After propensity score matching, we compared 62 P-PD with 62 age- and sex-matched controls. In addition, we performed regression analyses on the total sample (n = 271). In a second set of analyses, we used, a.o., the CUPRO to evaluate retrograde procedural memory and visuo-constructive functions. Results: People with P-PD showed significantly poorer performances in global cognition, visuo-constructive and executive functions, mainly in mental flexibility (p < 0.001; p = 0.004; p = 0.003), despite similar educational levels (p = 0.415). We observed significantly more motor and non-motor symptoms (p < 0.001; p = 0.004), higher scores for depression (p = 0.004) and apathy (p < 0.001) as well as lower quality of life (p < 0.001) in P-PD. CONCLUSIONS: Our findings confirm that global cognitive, executive, and visuo-constructive deficits define the P-PD group. In addition, depression, apathy, and lower quality of life were more prevalent in P-PD. If replicated in other samples, executive and visuo-constructive deficits should be considered in non-motor P-PD. Determining specific patterns will support early recognition of PD, secondary prevention of complications and the development of neuroprotective treatments.3. Good health and well-bein
Genetic complexity of miscanthus cell wall composition and biomass quality for biofuels
BACKGROUND: Miscanthus sinensis is a high yielding perennial grass species with great potential as a bioenergy feedstock. One of the challenges that currently impedes commercial cellulosic biofuel production is the technical difficulty to efficiently convert lignocellulosic biomass into biofuel. The development of feedstocks with better biomass quality will improve conversion efficiency and the sustainability of the value-chain. Progress in the genetic improvement of biomass quality may be substantially expedited by the development of genetic markers associated to quality traits, which can be used in a marker-assisted selection program. RESULTS: To this end, a mapping population was developed by crossing two parents of contrasting cell wall composition. The performance of 182 F1 offspring individuals along with the parents was evaluated in a field trial with a randomized block design with three replicates. Plants were phenotyped for cell wall composition and conversion efficiency characters in the second and third growth season after establishment. A new SNP-based genetic map for M. sinensis was built using a genotyping-by-sequencing (GBS) approach, which resulted in 464 short-sequence uniparental markers that formed 16 linkage groups in the male map and 17 linkage groups in the female map. A total of 86 QTLs for a variety of biomass quality characteristics were identified, 20 of which were detected in both growth seasons. Twenty QTLs were directly associated to different conversion efficiency characters. Marker sequences were aligned to the sorghum reference genome to facilitate cross-species comparisons. Analyses revealed that for some traits previously identified QTLs in sorghum occurred in homologous regions on the same chromosome. CONCLUSION: In this work we report for the first time the genetic mapping of cell wall composition and bioconversion traits in the bioenergy crop miscanthus. These results are a first step towards the development of marker-assisted selection programs in miscanthus to improve biomass quality and facilitate its use as feedstock for biofuel production
Determinants of patient-reported functional mobility in people with Parkinson's disease: A systematic review.
peer reviewed[en] BACKGROUND: Information on determinants of patient-reported functional mobility is lacking but would inform the planning of healthcare, resources and strategies to promote functional mobility in people with Parkinson's disease (PD).
RESEARCH QUESTION: To identify the determinants of patient-reported functional mobility of people with PD.
METHODS: Eligible: Randomized Controlled Trials, cohort, case-control, or cross-sectional analyses in people PD without date or setting restrictions, published in English, German, or French. Excluded: instruments with under 50 % of items measuring mobility. On August 9th 2023 we last searched Medline, CINAHL and PsychInfo. We assessed risk of bias using the mixed-methods appraisal tool. Results were synthesized by tabulating the determinants by outcomes and study designs.
RESULTS: Eleven studies published 2012-2023 were included (most in Swedish outpatient settings). Samples ranged from 9 to 255 participants. Follow-up varied from 1.5 to 36 months with attrition of 15-42 %. Heterogenic study designs complicated results synthesis. However, determinants related to environment seem to associate the strongest with patient-reported functional mobility, although determinants related to body structures and functions were most investigated. We identified disease duration, the ability to drive, caregiving, sex, age, cognitive impairment, postural instability and social participation as determinants of patient-reported functional mobility.
DISCUSSION: Methodological quality of the studies was limited. No study reported an a priori power calculation. Three studies controlled for confounders. The included studies lack representativeness of the population of people living with PD. Standardized sets of outcomes could enable more systematic research synthesis.
CONCLUSIONS: Future research should focus on activities, participation and environmental factors and improve methodological quality
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