A Finite Element Method for Interactive Physically Based Shape Modelling with Quadratic Tetrahedra

We present an alternative approach to standard geometric shape editing using physically-based simulation. With our technique, the user can deform complex objects in real-time. The enabling technology of this approach is a fast and accurate finite element implementation of an elasto-plastic material model, specifically designed for interactive shape manipulation. Using quadratic shape functions, we avoid the inherent drawback of volume locking exhibited by methods based on linear finite elements. The physical simulation uses a tetrahedral mesh, which is constructed from a coarser approximation of the detailed surface. Having computed a deformed state of the tetrahedral mesh, the deformation is transferred back to the high detail surface. This can be accomplished in an accurate and efficient way using the quadratic shape functions. In order to guarantee stability and real-time frame rates during the simulation, we cast the elasto-plastic problem into a linear formulation. For this purpose, we present a corotational formulation for quadratic finite elements. We demonstrate the versatility of our approach in interactive manipulation sessions and show that our animation system can be coupled with further physics-based animations like, e.g. fluids and cloth, in a bi-directional way

Cerebral vein thrombosis: clinical manifestation and diagnosis

BACKGROUND: Cerebral venous thrombosis (CVT) is a disease with a wide spectrum of symptoms and severity. In this study we analysed the predictive value of clinical signs and symptoms and the contribution of D-dimer measurements for diagnosis. METHODS: We evaluated consecutive patients admitted with suspected CVT receiving non-invasive imaging. Symptoms and symptom combination as well as D-dimer levels were evaluated regarding their diagnostic value. RESULTS: 239 patients were included in this study, 170 (71%) were females. In 39 patients (16%) a CVT was found. For identifying a CVT patients underwent either a venous CT-angiography or MR-angiography or both. No combination of symptoms either alone or together with the D-dimer measurements had a sensitivity and positive predictive value as well as negative predictive value and specificity high enough to serve as red flag. D-dimer testing produced rates of 9% false positive and of 24% false negative results. For D-dimer values a Receiver Operating Characteristic curve (ROC) and the area under the curve (AUC = 0.921; CI: 0.864 - 0.977) were calculated. An increase of sensitivity above 0.9 results in a relevant decrease in specificity; a sensitivity of 0.9 matches a specificity value of 0.9. This corresponds to a D-dimer cut-off level of 0.16 μg/ml. CONCLUSION: Imaging as performed by venous CT-angiography or MR-angiography has a 1 to 2 in 10 chance to detect CVT when typical symptoms are present. D-dimer measurements are of limited clinical value because of false positive and negative results

Do self-reported hearing and visual impairments predict longitudinal dementia in older adults?

Background Sensory impairments have been associated with dementia in older adults. However, the contribution of different impairments and how they interact in the development of dementia is not clear. We examined the independent and interaction effects of hearing impairment (HI) and visual impairment (VI) on incident dementia. Design Multi-centric population-based prospective cohort study. Setting Data were taken from the AgeDifferent.de platform, pooling participants aged 75 and older from the German LEILA75+ and AgeCoDe/AgeQualiDe cohorts. Participants Older adults (N = 3497) with mean age 79.8 years, 67.2% female. Measurements Standardized interviews and questionnaires were used to assess self-reported HI and VI at baseline and all-cause dementia in 9 follow-ups, spanning over 20 years. Methods Competing risk regression models were conducted to test the main and interaction effects of HI and VI on dementia incidence, adjusting for established risk factors of dementia and accumulated mortality. Results HI and VI at baseline were reported by 30.3% and 16.6% of individuals, respectively. Adjusting for baseline information on sociodemographics, substance use, cognitive functioning and morbidity, and controlling for accumulated mortality risk, HI (sHR 1.16, 95% CI 1.04–1.30, p = 0.011) but not VI (sHR 1.07, 95% CI 0.90–1.28, p = 0.462) was significantly associated with incident dementia. There was no interaction between HI and VI (sHR 1.09, 95% CI 0.81–1.46, p = 0.567). Conclusions Hearing impairment is associated with an increased incidence of all-cause dementia in older adults. There is no excess risk or risk compensation through the additional presence or absence of visual impairment. Early prevention measures for hearing impairment might help to reduce the long-term risk of dementia

Factors associated with shunt dynamic in patients with cryptogenic stroke and patent foramen ovale: an observational cohort study

<p>Abstract</p> <p>Background</p> <p>As previously reported there is evidence for a reduction in right to left shunt (RLS) in stroke patients with patent foramen ovale (PFO). This occurs predominantly in patients with cryptogenic stroke (CS). We therefore analysed factors associated with a shunt reduction on follow-up in stroke patients suffering of CS.</p> <p>Methods</p> <p>On index event PFO and RLS were proven by transesophageal echocardiography and contrast-enhanced transcranial Doppler-sonography (ce-TCD). Silent PE was proved by ventilation perfusion scintigraphy (V/Q) within the stroke work-up on index event; all scans were re-evaluated in a blinded manner by two experts. The RLS was re-assessed on follow-up by ce-TCD. A reduction in shunt volume was defined as a difference of ≥20 microembolic signals (MES) or the lack of evidence of RLS on follow-up. For subsequent analyses patients with CS were considered; parameters such as deep vein thrombosis (DVT) and silent pulmonary embolism (PE) were analysed.</p> <p>Results</p> <p>In 39 PFO patients suffering of a CS the RLS was re-assessed on follow-up. In all patients (n = 39) with CS a V/Q was performed; the median age was 40 years, 24 (61.5%) patients were female. In 27 patients a reduction in RLS was evident. Silent PE was evident in 18/39 patients (46.2%). Factors such as atrial septum aneurysm, DVT or even silent PE were not associated with RLS dynamics. A greater time delay from index event to follow-up assessment was associated with a decrease in shunt volume (median 12 vs. 6 months, <it>p </it>= 0.013).</p> <p>Conclusions</p> <p>In patients with CS a reduction in RLS is not associated with the presence of a venous embolic event such as DVT or silent PE. A greater time delay between the initial and the follow-up investigation increases the likelihood for the detection of a reduction in RLS.</p

The Role of Social Isolation and the Development of Depression: A Comparison of the Widowed and Married Oldest Old in Germany

Widowhood is common in old age, can be accompanied by serious health consequences and is often linked to substantial changes in social network. Little is known about the impact of social isolation on the development of depressive symptoms over time taking widowhood into account. We provide results from the follow-up 5 to follow-up 9 from the longitudinal study AgeCoDe and its follow-up study AgeQualiDe. Depression was measured with GDS-15 and social isolation was assessed using the Lubben Social Network Scale (LSNS-6). The group was aligned of married and widowed people in old age and education through entropy balancing. Linear mixed models were used to examine the frequency of occurrence of depressive symptoms for widowed and married elderly people depending on the risk of social isolation. Our study shows that widowhood alone does not lead to an increased occurrence of depressive symptoms. However, "widowed oldest old", who are also at risk of social isolation, have significantly more depressive symptoms than those without risk. In the group of "married oldest old", women have significantly more depressive symptoms than men, but isolated and non-isolated do not differ. Especially for people who have lost a spouse, the social network changes significantly and increases the risk for social isolation. This represents a risk factor for the occurrence of depressive symptoms

Incidence of Anxiety in Latest Life and Risk Factors. Results of the AgeCoDe/AgeQualiDe Study

Research on anxiety in oldest-old individuals is scarce. Specifically, incidence studies based on large community samples are lacking. The objective of this study is to assess age- and gender-specific incidence rates in a large sample of oldest-old individuals and to identify potential risk factors. The study included data from N = 702 adults aged 81 to 97 years. Anxiety symptoms were identified using the short form of the Geriatric Anxiety Inventory (GAI-SF). Associations of potential risk factors with anxiety incidence were analyzed using Cox proportional hazard models. Out of the N = 702 older adults, N = 77 individuals developed anxiety symptoms during the follow-up period. The incidence rate was 51.3 (95% CI: 41.2–64.1) per 1000 person-years in the overall sample, compared to 58.5 (95% CI: 43.2–72.4) in women and 37.3 (95% CI: 23.6–58.3) in men. Multivariable analysis showed an association of subjective memory complaints (HR: 2.03, 95% CI: 1.16–3.57) and depressive symptoms (HR: 3.20, 95% CI: 1.46–7.01) with incident anxiety in the follow-up. Incident anxiety is highly common in late life. Depressive symptoms and subjective memory complaints are major risk factors of new episodes. Incident anxiety appears to be a response to subjective memory complaints independent of depressive symptoms

Frequency and gender differences in the use of professional home care in late life: Findings from three German old-age cohorts

Aim: The aim of this study was to investigate the frequency of and the gender differences in the use of professional home care in Germany. Methods: We used harmonized data from three large cohort studies from Germany (“Healthy Aging: Gender-specific trajectories into the latest life”; AgeDifferent.de Platform). Data were available for 5,393 older individuals (75 years and older). Mean age was 80.2 years (SD: 4.1 years), 66.6% were female. Professional homecare outcome variables were use of outpatient nursing care, paid household assistance, and meals on wheels’ services. Logistic regression models were used, adjusting for important sociodemographic variables. Results: Altogether 5.2% of older individuals used outpatient nursing care (6.2% women and 3.2% men; p < 0.001), 24.2% used paid household assistance (26.1% women and 20.5% men; p < 0.001) and 4.4% used meals on wheels’ services (4.5% women and 4.0% men; p = 0.49). Regression analysis revealed that women had higher odds of using paid household assistance than men (OR = 1.48, 95% CI: [1.24–1.76]; p < 0.001), whereas they had lower odds of using meals on wheels’ services (OR = 0.64, 95% CI: [0.42–0.97]; p < 0.05). No statistically significant differences in using outpatient nursing care between women and men were found (OR = 1.26, 95% CI: [0.87–1.81]; p = 0.225). Further, the use of home care was mainly associated with health-related variables (e.g., stroke, Parkinson’s disease) and walking impairments. Conclusions: Our study showed that gender differences exist in using paid household assistance and in culinary dependency. For example, meals on wheels’ services are of great importance (e.g., for individuals living alone or for individuals with low social support). Gender differences were not identified regarding outpatient nursing care. Use of professional home care servicesmay contribute to maintaining autonomy and independence in old age

AgeWell.de – study protocol of a pragmatic multi-center cluster-randomized controlled prevention trial against cognitive decline in older primary care patients

Background: In the absence of treatment options, the WHO emphasizes the identification of effective prevention strategies as a key element to counteract the dementia epidemic. Regarding the complex nature of dementia, trials simultaneously targeting multiple risk factors should be particularly effective for prevention. So far, however, only few such multi-component trials have been launched, but yielding promising results. In Germany, comparable initiatives are lacking, and translation of these complex interventions into routine care was not yet done. Therefore, AgeWell.de will be conducted as the first multi-component prevention trial in Germany which is closely linked to the primary care setting. Methods: AgeWell.de will be designed as a multi-centric, cluster-randomized controlled multi-component prevention trial. Participants will be older community-dwelling general practitioner (GP) patients (60–77 years; n = 1,152) with increased dementia risk according to CAIDE (Cardiovascular Risk Factors, Aging, and Incidence of Dementia) Dementia Risk Score. Recruitment will take place at 5 study sites across Germany. GP practices will be randomized to either intervention A (advanced) or B (basic). GPs will be blinded to their respective group assignment, as will be the statistician conducting the randomization. The multi-component intervention (A) includes nutritional counseling, physical activity, cognitive training, optimization of medication, management of vascular risk factors, social activity, and, if necessary, further specific interventions targeting grief and depression. Intervention B includes general health advice on the intervention components and GP treatment as usual. We hypothesize that over the 2-year follow-up period the intervention group A will benefit significantly from the intervention program in terms of preserved cognitive function/delayed cognitive decline (primary outcome), and other relevant (secondary) outcomes (e.g. quality of life, social activities, depressive symptomatology, cost-effectiveness). Discussion: AgeWell.de will be the first multi-component trial targeting risk of cognitive decline in older adults in Germany. Compared to previous trials, AgeWell.de covers an even broader set of interventions suggested to be beneficial for the intended outcomes. The findings will add substantial knowledge on modifiable lifestyle factors to prevent or delay cognitive decline. Trial registration: German Clinical Trials Register (reference number: DRKS00013555)