Why Do Cascade Sizes Follow a Power-Law?

We introduce random directed acyclic graph and use it to model the information diffusion network. Subsequently, we analyze the cascade generation model (CGM) introduced by Leskovec et al. [19]. Until now only empirical studies of this model were done. In this paper, we present the first theoretical proof that the sizes of cascades generated by the CGM follow the power-law distribution, which is consistent with multiple empirical analysis of the large social networks. We compared the assumptions of our model with the Twitter social network and tested the goodness of approximation.Comment: 8 pages, 7 figures, accepted to WWW 201

Studying feasibility and effects of a two-stage nursing staff training in residential geriatric care using a 30 month mixed-methods design [ISRCTN24344776]

<p>Abstract</p> <p>Background</p> <p>Transfer techniques and lifting weights often cause back pain and disorders for nurses in geriatric care. The Kinaesthetics care conception claims to be an alternative, yielding benefits for nurses as well as for clients.</p> <p>Starting a multi-step research program on the effects of Kinaesthetics, we assess the feasibility of a two-stage nursing staff training and a pre-post research design. Using quantitative and qualitative success criteria, we address mobilisation from the bed to a chair and backwards, walking with aid and positioning in bed on the staff level as well as on the resident level. In addition, effect estimates should help to decide on and to prepare a controlled trial.</p> <p>Methods/Design</p> <p>Standard basic and advanced Kinaesthetics courses (each comprising four subsequent days and an additional counselling day during the following four months) are offered to n = 36 out of 60 nurses in a residential geriatric care home, who are in charge of 76 residents. N = 22 residents needing movement support are participating to this study.</p> <p>On the staff level, measurements include focus group discussions, questionnaires, physical strain self-assessment (Borg scale), video recordings and external observation of patient assistance skills using a specialised instrument (SOPMAS). Questionnaires used on the resident level include safety, comfort, pain, and level of own participation during mobilisation. A functional mobility profile is assessed using a specialised test procedure (MOTPA).</p> <p>Measurements will take place at baseline (T0), after basic training (T1), and after the advanced course (T2). Follow-up focus groups will be offered at T1 and 10 months later (T3).</p> <p>Discussion</p> <p>Ten criteria for feasibility success are established before the trial, assigned to resources (missing data), processes (drop-out of nurses and residents) and science (minimum effects) criteria. This will help to make rational decision on entering the next stage of the research program.</p> <p>Trial Registration</p> <p>Current Controlled Trials <a href="http://www.controlled-trials.com/ISRCTN24344776">ISRCTN24344776</a>.</p

Anisotropy of the effective toughness of layered media

This continues the study of the effective toughness of layered materials started in Hossain et al. (2014) and Hsueh et al. (2018), with a focus on anisotropy. We use the phase-field model and the surfing boundary condition to propagate a crack macroscopically at various angles to the layers. We study two idealized situations, the first where the elastic modulus is uniform while the toughness alternates and a second where the toughness is uniform and the elastic modulus alternates. We find that in the first case of toughness heterogeneity the effective toughness displays ‘anomalous isotropy’ in that it is independent of the propagation direction and equal to that of the tougher material except when the crack propagation is parallel to the layers. In the second case of elastic heterogeneity, we find the behavior more anisotropic and consistent with the toughening effects of stress fluctuation and need for crack renucleation at the compliant-to-stiff interface. In both cases, the effective toughness is not convex in the sense of interfacial energy or Wulff shape reflecting the fact that crack propagation follows a critical path. Further, in both cases the crack path is not straight and consistent with a maximal dissipation principle. Finally, the effective toughness depends on the contrast and pinning, rather than on the extent of crack fluctuation

Cost-effectiveness of cognitive-behavioral group therapy for dysfunctional fear of progression in cancer patients

Anxiety and fear are often associated with chronic conditions such as cancer. This paper targets the cost-effectiveness analysis of a cognitive-behavioral group therapy (CBT) in comparison to a client-centered, supportive-experiential group therapy (SET) in cancer patients with dysfunctional fear of progression. An incremental cost-effectiveness analysis was performed using data from a randomized controlled trial among cancer patients receiving inpatient rehabilitation. The means, 95% confidence intervals [95% CI], incremental cost-effectiveness graphic and acceptability curve were obtained from 1,000 bootstrap replications. A total of 174 patients were included in the economic evaluation. The estimated means [95% CI] of direct costs and reduction of fear of progression were €9,045.03 [6,359.07; 12,091.87] and 1.41 [0.93; 1.92] for patients in the SET and €6,682.78 [4,998.09; 8,440.95] and 1.44 [1.02; 1.09] for patients in the CBT. The incremental cost-effectiveness ratio [95% CI] amounts to minus €78,741.66 [−154,987.20; 110,486.32] for an additional unit of effect. Given the acceptability curve, there is a 92.4% chance that the CBT, compared with the SET, is cost-effective without the need of additional costs to payers. Our main result is the superior cost-effectiveness of the cognitive-behavioral intervention program in comparison to the non-directive encounter group for our sample of cancer patients with high levels of anxiet

Cohort Profile of the International Spinal Cord Injury Community Survey Implemented in 22 Countries

Objectives: To detail the methodological features of the first International Spinal Cord Injury (InSCI) Community Survey by describing recruitment and data collection procedures, and to report on the recruitment results and basic characteristics of participants by country and income setting. Design: Cross-sectional survey. Setting: Community setting in 22 countries representing all 6 World Health Organization regions. Participants: Individuals (N = 12,591) with traumatic or non-traumatic spinal cord injury (SCI) aged over 18 years. Interventions: Not applicable. Main Outcome Measures: Recruitment and data collection procedures, recruitment results, and basic sociodemographic and lesion characteristics of participants. Results: Eight countries used predefined sampling frames and 14 countries applied convenience sampling for recruitment. Most countries recruited participants through specialized rehabilitation facilities, patient organizations, or acute and general hospitals. Modes of approaching potential participants depended on the sampling strategy and multiple response modes were offered to maximize participation. Contact rates ranged from 33% to 98%, cooperation rates ranged from 29% to 90%, and response rates ranged from 23% to 54%. The majority of participants were men (73%), the median age was 52 years (interquartile range, 40-63y), 60% had a partner, 8% reported that they were born in another country than where they were currently residing, and the median length of education was 12 years (interquartile range, 9-15y). Paraplegia was the main diagnosis (63%), traumatic etiologies were the major cause of injury (81%), and the median time since injury (TSI) was 9 years (interquartile range, 4-19y). Compared with participants from lower income settings, participants from higher income settings were over-represented and, in general, were older, more often diagnosed with tetraplegia, had a longer TSI, higher education, and were more often born in a country different than their current residence country. Conclusions: The successful implementation of the InSCI survey enables the comparison of the situation of individuals with SCI around the world and constitutes a crucial starting point for an international learning experience. (C) 2020 by the American Congress of Rehabilitation Medicin

Towards comprehensive and transparent reporting: context-specific additions to the ICF taxonomy for medical evaluations of work capacity involving claimants with chronic widespread pain and low back pain

BACKGROUND: Medical evaluations of work capacity provide key information for decisions on a claimant's eligibility for disability benefits. In recent years, the evaluations have been increasingly criticized for low transparency and poor standardization. The International Classification of Functioning, Disability and Health (ICF) provides a comprehensive spectrum of categories for reporting functioning and its determinants in terms of impairments and contextual factors and could facilitate transparent and standardized documentation of medical evaluations of work capacity. However, the comprehensiveness of the ICF taxonomy in this particular context has not been empirically examined. In this study, we wanted to identify potential context-specific additions to the ICF for its application in medical evaluations of work capacity involving chronic widespread pain (CWP) and low back pain (LBP).METHODS: A retrospective content analysis of Swiss medical reports was conducted by using the ICF for data coding. Concepts not appropriately classifiable with ICF categories were labeled as specification categories (i.e. context-specific additions) and were assigned to predefined specification areas (i.e. precision, coverage, personal factors, and broad concepts). Relevant specification categories for medical evaluations of work capacity involving CWP and LBP were determined by calculating their relative frequency across reports and setting a relevance threshold.RESULTS: Forty-three specification categories for CWP and fifty-two for LBP reports passed the threshold. In both groups of reports, precision was the most frequent specification area, followed by personal factors.CONCLUSIONS: The ICF taxonomy represents a universally applicable standard for reporting health and functioning information. However, when applying the ICF for comprehensive and transparent reporting in medical evaluations of work capacity involving CWP and LBP context-specific additions are needed. This is particularly true for the documentation of specific pain-related issues, work activities and personal factors. To ensure the practicability of the multidisciplinary evaluation process, the large number of ICF categories and context-specific additions necessary for comprehensive documentation could be specifically allocated to the disciplines in charge of their assessment.<br/

Morphological dynamics of the islands on the lower Danube river in the Călărași-Cernavodă sector and GIS error assessment

A diachronic analysis of the geomorphic units using a geographical information system (GIS) that integrates historical maps, aerial and satellite imagery is a useful method to explore fluvial morphodynamics. This study used the mentioned spatial data sources to investigate the morphological changes of the islands on the Low Danube River between Călărași and Cernavodă between 1864 and 2016. At the same time, the accuracy of the cartographic materials was evaluated to differentiate between real change caused by identification or positional errors. There is a general increase in area and number of islands in the study area in the context of decreasing sediment volume transported by the Danube

Tau mutation S356T in the three repeat isoform leads to microtubule dysfunction and promotes prion-like seeded aggregation

Tauopathies are a group of neurodegenerative diseases, which include frontotemporal dementia (FTD) and Alzheimer’s disease (AD), broadly defined by the development of tau brain aggregates. Both missense and splicing tau mutations can directly cause early onset FTD. Tau protein is a microtubule-associated protein that stabilizes and regulates microtubules, but this function can be disrupted in disease states. One contributing factor is the balance of different tau isoforms, which can be categorized into either three repeat (3R) or four repeat (4R) isoforms based on the number of microtubule-binding repeats that are expressed. Imbalance of 3R and 4R isoforms in either direction can cause FTD and neurodegeneration. There is also increasing evidence that 3R tauopathies such as Pick’s disease form tau aggregates predominantly comprised of 3R isoforms and these can present differently from 4R and mixed 3R/4R tauopathies. In this study, multiple mutations in 3R tau were assessed for MT binding properties and prion-like aggregation propensity. Different missense tau mutations showed varying effects on MT binding depending on molecular location and properties. Of the mutations that were surveyed, S356T tau is uniquely capable of prion-like seeded aggregation and forms extensive Thioflavin positive aggregates. This unique prion-like tau strain will be useful to model 3R tau aggregation and will contribute to the understanding of diverse presentations of different tauopathies