13 research outputs found
The impact of organic material for macrophytes in coastal waters of the Baltic Sea
Gelöster organischer Stickstoff (DON) als Nährstoff und sein Einfluss auf das Wachstum von Makrophyten der Darss-Zingster Boddenkette (DZBK) wurde mit Hilfe von stabilen Stickstoffisotopen untersucht. Die Aufnahme von labilen Komponenten des DON (z.B. Aminosäuren) über ober- als auch unterirdische Pflanzenteile konnte experimentell nachgewiesen werden. Die DON-Konzentrationen der DZBK sind im Jahresgang konstant, damit steht DON als Nährstoff potentiell zur Verfügung. Der Vergleich der delta15N-Werte von Makrophyten und DON hat gezeigt, dass DON im Freiland von Makrophyten aufgenommen wird.Dissolved organic nitrogen as nutrient and its influence on the growth of macrophytes in the Darss-Zingst bodden chain (DZBC) was investigated with nitrogen stable isotopes analyses. The uptake of labile components of DON (e.g. amino acids) via above- and belowground plant parts was proven experimentally. DON concentrations were consistently high over a year, thus DON is available as nutrient in principal. The comparison of the delta15N values of macrophytes and DON has shown that DON is taken up in the field by macrophytes
Social Entrepreneurship Research as a Means of Transformation: A Vision for the Year 2028
In this essay we suggest directions and perspectives for social entrepreneurship research that could result in a state in which social entrepreneurship would have become mainstream. This includes the need to delineate and define social entrepreneurship vis-à-vis commercial entrepreneurship, the question of growth and scaling up of social ventures, the role of social entrepreneurship on a macroeconomic level, and the use of critical theory as a theoretical lens. Our recommendations are inspired by a Professional Development Workshop on ‘Social Entrepreneurship: Future Directions in Education and Research’ organized by the authors at the Academy of Management Conference 2010 in Montréal
Development and validation of the deep brain stimulation impairment scale (DBS-IS)
Background: Bilateral deep brain stimulation of the subthalamic nucleus (STN-DBS) has considerable influence on motor and non-motor symptoms in Parkinson's disease (PD). While improvements in motor functioning can be easily assessed with general quality of life questionnaires, the measurement of specific STN-DBS-associated impairments often remains insufficient. Hence, we aimed to develop a questionnaire that measures STN-DBS-related impairments. Methods: The development of the (STN-)DBS Impairment Scale (DBS-IS) consisted of four steps. First, 30 semi-structured interviews before, three and twelve months after STN-DBS-surgery were performed to create 76 items that relate to motor and non-motor functioning in STN-DBS PD patients. Second, pilot testing led to a rewording of the questions for better understanding. Third, a first multicentre survey was performed to reduce items by applying principal component analysis (PCA). Fourth, a second multicentre survey was conducted to examine factor structure, reliability (internal consistency) and validity. Results: After the first survey (N = 215), the PCA lead to a reduction of 54 items. After the second survey (N = 391), exploratory factor analysis determined six factors with 22 items: 1. Postural instability and gait difficulties (5 items), 2. Cognitive impairment (5 items), 3. Speaking problems (3 items), 4. Apathy (3 items), 5. Impulsivity (3 items), and 6. Difficulties related to the DBS device (3 items). High reliability was reported for all subscales (Cronbach's alpha 0.71-0.90). Similarly, construct validity was high (r > 0.50, p < 0.001). Conclusions: With this new questionnaire patients can be followed-up and STN-DBS-specific problems might be adequately measured. Also, comparisons between patients with and without STN-DBS might be possible.(C) 2017 Elsevier Ltd. All rights reserved
The Deep Brain Stimulation Impairment Scale: A useful complement in assessment of well-being and functioning in DBS-patients - Results from a large multicentre survey in patients with Parkinson's disease
Background: Deep Brain Stimulation (DBS) has been proven to alleviate motor symptoms in Parkinson's Disease (PD). Regarding non-motor symptoms, however, inconsistencies have been reported, on whether DBS causes reductions in well-being and functioning. To assess motor and non-motor impairment in DBS-patients, the Deep Brain Stimulation Impairment Scale (DBS-IS) has been developed. Yet, the extent to which the DBS-IS detects impairment in DBS-patients and thus could serve as a useful tool that complements the PDQ-39 (gold standard) in assessment of well-being and functioning in PD-patients has not been shown. Objectives: By comparing DBS and non-DBS-patients we aimed to identify DBS-specific symptoms. We thereby aimed to show in how far the DBS-IS complements the PDQ-39 in assessing well-being and functioning in PD patients under DBS. Methods: In a cross-sectional study, 186 DBS-patients were matched (for age, disease duration and sex) to 186 non-DBS-patients (N = 372) and the two groups were compared regarding well-being and functioning: Impairment was assessed via DBS-IS and overall Quality of Life (QoL) was assessed via PDQ-39. Additionally, we analyzed differences in impairment between age and disease duration clusters. Results: DBS-patients showed significantly higher total impairment (DBS-IS) and significantly higher impairment on the subscales Postural Instability and Gait difficulties and speaking difficulties than non-DBS-patients. Impairment increased with age and disease duration and, overall, differences in impairment rose by age. Overall QoL (PDQ-39) was non-significantly lower in DBS-patients. Conclusion: Since there is evidence that the PDQ-39 misses some DBS-specific symptoms, the DBS-IS is recom-mended to complement the PDQ-39 when assessing DBS-patients