| 1. |
- Huertas-Hernando, D., et al.
(författare)
-
Hydro power flexibility for power systems with variable renewable energy sources : An IEA Task 25 collaboration
- 2016
-
Ingår i: Wiley Interdisciplinary Reviews. - : John Wiley & Sons. - 2041-8396 .- 2041-840X.
-
Tidskriftsartikel (refereegranskat)abstract
- Hydro power is one of the most flexible sources of electricity production. Power systems with considerable amounts of flexible hydro power potentially offer easier integration of variable generation, e.g., wind and solar. However, there exist operational constraints to ensure mid-/long-term security of supply while keeping river flows and reservoirs levels within permitted limits. In order to properly assess the effective available hydro power flexibility and its value for storage, a detailed assessment of hydro power is essential. Due to the inherent uncertainty of the weather-dependent hydrological cycle, regulation constraints on the hydro system, and uncertainty of internal load as well as variable generation (wind and solar), this assessment is complex. Hence, it requires proper modeling of all the underlying interactions between hydro power and the power system, with a large share of other variable renewables. A summary of existing experience of wind integration in hydro-dominated power systems clearly points to strict simulation methodologies. Recommendations include requirements for techno-economic models to correctly assess strategies for hydro power and pumped storage dispatch. These models are based not only on seasonal water inflow variations but also on variable generation, and all these are in time horizons from very short term up to multiple years, depending on the studied system. Another important recommendation is to include a geographically detailed description of hydro power systems, rivers' flows, and reservoirs as well as grid topology and congestion.
|
|
| 2. |
- Religa, D., et al.
(författare)
-
SveDem, the Swedish Dementia Registry - A tool for improving the quality of diagnostics, treatment and care of dementia patients in clinical practice
- 2015
-
Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 10:2
-
Tidskriftsartikel (refereegranskat)abstract
- Background: The Swedish Dementia Registry (SveDem) was developed with the aim to improve the quality of diagnostic work-up, treatment and care of patients with dementia disorders in Sweden. Methods: SveDem is an internet based quality registry where several indicators can be followed over time. It includes information about the diagnostic work-up, medical treatment and community support (www.svedem.se). The patients are diagnosed and followed-up yearly in specialist units, primary care centres or in nursing homes. Results: The database was initiated in May 2007 and covers almost all of Sweden. There were 28 722 patients registered with a mean age of 79.3 years during 2007-2012. Each participating unit obtains continuous online statistics from its own registrations and they can be compared with regional and national data. A report from SveDem is published yearly to inform medical and care professionals as well as political and administrative decision-makers about the current quality of diagnostics, treatment and care of patients with dementia disorders in Sweden. Conclusion: SveDem provides knowledge about current dementia care in Sweden and serves as a framework for ensuring the quality of diagnostics, treatment and care across the country. It also reflects changes in quality dementia care over time. Data from SveDem can be used to further develop the national guidelines for dementia and to generate new research hypotheses.
|
|
| 3. |
|
|
| 4. |
- Bergman, Eva-Mathilda, et al.
(författare)
-
National registry-based case-control study : comorbidity and stroke in young adults
- 2015
-
Ingår i: Acta Neurologica Scandinavica. - : Hindawi Limited. - 0001-6314 .- 1600-0404. ; 131:6, s. 394-399
-
Tidskriftsartikel (refereegranskat)abstract
- ObjectivesStroke is overrepresented in cohorts of young adults with chronic diseases. The prevalence and impact of comorbidity among young stroke patients have not been compared with individuals without stroke. Our aim was to investigate the association between comorbidity and stroke in young adults. Materials and methodsA nationwide cohort of patients (aged 15-44years), registered in the Swedish Stroke Register, (Riksstroke) 2001-2009, was identified. Age- and sex-matched controls were randomly selected from the Population Register of Sweden. Discharge diagnoses were retrieved from the National Patient Register and grouped by chapter in the International Classification of Diseases 10th revision. Associations between ICD-10 chapters and stroke were stratified (age, sex, and stroke type) and analyzed by multivariable logistic regression. ResultsIn 2599 stroke patients analyzed, the prevalence of vascular risk factors (hypertension 25.3%, dyslipidemia 13.0%, diabetes 9.7%, heart failure 3.2%, and atrial fibrillation 2.8%), all ICD-10 chapters (except pregnancy) and prestroke hospitalizations were more frequent among cases than controls. Independent associations were found between stroke and eight ICD-10 chapters: neoplasms (odds ratios (OR) 1.53, 95% CI 1.15-2.05), blood (OR 1.61, 1.11-2.34), endocrine (OR 2.28, 1.77-2.93), psychiatric (OR 1.50, 1.24-1.81), nervous (OR 1.91, 1.46-2.50), eye (OR 1.67, 1.05-2.64), circulatory (OR 3.05, 2.45-3.80), and symptoms (OR 1.31, 1.13-1.52). The risk of stroke increased by 26% per ICD-10 chapter diagnosed. ConclusionsIn addition to vascular risk factors, comorbidity (represented by ICD-10 chapters) was associated with increased risk of stroke in young individuals. The risk of stroke was further increased with the number of diagnosed ICD-10 chapters.
|
|
| 5. |
- Enache, D, et al.
(författare)
-
Medial temporal lobe atrophy and depressive symptoms in elderly patients with and without Alzheimer disease
- 2015
-
Ingår i: Journal of geriatric psychiatry and neurology. - : SAGE Publications. - 0891-9887 .- 1552-5708. ; 28:1, s. 40-48
-
Tidskriftsartikel (refereegranskat)abstract
- To determine whether depressive symptoms are associated with medial temporal lobe atrophy in older people with and without Alzheimer disease (AD).Method:A total of 368 memory clinic patients with AD, mild cognitive impairment, and subjective cognitive impairment (SCI) were included. Depressive symptoms were defined as a score of 8 or higher on Cornell Scale for Depression in Dementia or use of antidepressant medications. Magnetic resonance imaging and computer tomography scans were rated for medial temporal lobe atrophy (MTA), using the Scheltens scale. For a subsample (n = 57 patients), hippocampal volume was manually traced.Results:Based on visual assessment, AD patients with depressive symptoms had less atrophy of the right medial temporal lobe (odds ratio [OR] for having MTA: 0.39; 95% confidence interval [CI] 0.16-0.99) and decreased scores on Scheltens scale for the left medial temporal lobe (OR: 0.43, 95% CI 0.19-0.96) in comparison to AD patients without depressive symptoms. In the subgroup where manual tracing was used to measure hippocampal volume, people with SCI experiencing depressive symptoms had smaller right (mean difference: 0.28 cm3; P = .005) and left (mean difference 0.32 cm3; P = .002) hippocampal volumes compared to people with SCI who did not have depressive symptoms.Conclusion:Hippocampal atrophy was more pronounced among patients having SCI with depressive symptoms, while the medial temporal lobe was less atrophic in patients having AD with depressive symptoms than those without depressive symptoms. These findings suggest that different mechanisms underlie depression in older people with and without AD and may explain some of the inconsistent observations in previous studies.
|
|
| 6. |
- Huertas-Hernando, Daniel, et al.
(författare)
-
Hydropower Flexibility for Power Systems with Variable Renewable Energy Sources: An IEA Task 25 Collaboration
- 2019
-
Ingår i: Advances in Energy Systems. - : Wiley. ; , s. 385-405
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- In order to effectively utilize hydro production flexibility, a sufficient amount of transmission capacity has to be available between the hydro-dominated part of the system and the part that requires operational flexibility. This chapter starts with a rough categorization of “base” hydropower flexibility, investigating the types of hydropower plants installed in power systems today. The “effective” hydropower flexibility available to support the integration of variable generation is a far more complex and case-specific aspect. It is discussed through national experiences. The chapter presents potential developments that would increase the participation of hydropower and discuss the ensuing challenges. Modeling a flow-based hydro system is a complex exercise, as is modeling the power system. Especially important is the correct assessment of hydropower flexibility to support power systems with a large share of variable generation (VG) and its value for storage. With increasing uncertainty and variability, a stochastic scheduling approach should yield lower costs.
|
|
| 7. |
- Keshmiri, F., et al.
(författare)
-
Contextualization and validation of the interprofessional collaborator assessment rubric (ICAR) through simulation : Pilot investigation.
- 2016
-
Ingår i: Medical journal of the Islamic Republic of Iran. - : Iran University of Medical Sciences. - 1016-1430 .- 2251-6840. ; 30, s. 742-749
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND:Simulation can be used for educating, evaluating and assessing psychometric properties of an instrument. The aim of this study was to contextualize and assess the validity and reliability of the Interprofessional Collaborative Assessment tool (ICAR) in an Iranian context using simulation.METHODS:In this descriptive study, contextualization of the ICAR was assessed through several steps. Firstly, validity assessment was approved through expert panels and Delphi rounds. Secondly, reliability assessment was done by arranging a simulation video and assessing reproducibility, test-retest (ICC), internal consistency (Cronbach's Alpha) and inter-rater reliability (Kappa).The participants included 26 experts, 27 students and 6 staff of the Standardized Simulation Office of Teheran University of Medical Sciences.RESULTS:Contextualization and validity of the ICAR were approved in an Iranian context. The reliability of the tool was computed to be 0.71 according to Cronbach´s Alpha. The test-retest was calculated to be 0.76.CONCLUSION:The Iranian ICAR can be a useful tool for evaluating interprofessional collaborative competencies. The development of the instrument through a simulation scenario has been a positive prospect for researchers.
|
|
| 8. |
- Lund, Lars H, et al.
(författare)
-
Association between enrolment in a heart failure quality registry and subsequent mortality-a nationwide cohort study.
- 2017
-
Ingår i: European Journal of Heart Failure. - : John Wiley & Sons. - 1388-9842 .- 1879-0844.
-
Tidskriftsartikel (refereegranskat)abstract
- AIMS: Heart failure (HF) quality registries report quality of care but it is unknown whether they improve outcomes. The aims were to assess predictors of enrolment in a HF registry, test the hypothesis that enrolment in a HF registry is associated with reduced mortality, and assess potential explanatory factors for this reduction in mortality, if present.METHODS AND RESULTS: We conducted a nationwide prospective cohort study of patients with new-onset HF registered in the Swedish National Patient Registry (NPR, a mandatory registry of ICD-code diagnoses) with or without concurrent registration in the Swedish Heart Failure Registry (SwedeHF, a voluntary quality reporting registry) 2006-2013. The association between demographics, co-morbidities and medications, and enrolment in the SwedeHF, was assessed using multivariable logistic regression. The association between enrolment in the SwedeHF and all-cause mortality was assessed using multivariable Cox regression, with adjustment for demographics, co-morbidities and medications. A total of 231 437 patients were included, of which 21 888 (9.5%) were in the SwedeHF [age (mean ± standard deviation) 74 ± 13 years; 41% women; 68% inpatients] and 209 549 (90.5%) were not (age 78 ± 12 years, 50% women; 79% inpatients). Selected variables independently associated with enrolment in the SwedeHF were male sex, younger age, higher education, absent co-morbidities and co-morbidity-related medications, and use of HF and cardiovascular medications. Over a median (interquartile range) follow-up of 874 (247-1667) days, there were 13.0 vs. 20.8 deaths per 100 patient-years (P < 0.001). The hazard ratio (95% confidence interval) for death for the SwedeHF yes vs. no was 0.65 (0.63-0.66) crude, and increased to 0.80 (0.78-0.81) after adding demographics, to 0.82 (0.80-0.84) after adding co-morbidities and co-morbidity-related medications, to 0.95 (0.93-0.97) after adding cardiovascular medications, and to 1.04 (1.02-1.07) after adding HF-specific medications.CONCLUSION: Heart failure patients of male sex, younger age, and higher education were more likely to be enrolled in a HF quality registry. Enrolment was associated with reduced all-cause mortality that was explained by demographic differences and better utilization of cardiovascular and HF medications.
|
|
| 9. |
- Skillback, Tobias, et al.
(författare)
-
Cerebrospinal fluid tau and amyloid-beta(1-42) in patients with dementia
- 2015
-
Ingår i: Brain. - : Oxford University Press (OUP). - 0006-8950 .- 1460-2156. ; 138:9, s. 2716-2731
-
Tidskriftsartikel (refereegranskat)abstract
- Progressive cognitive decline in combination with a cerebrospinal fluid biomarker pattern of low levels of amyloid-beta(1-42) and high levels of total tau and phosphorylated tau is typical of Alzheimer's disease. However, several neurodegenerative disorders may overlap with Alzheimer's disease both in regards to clinical symptoms and neuropathology. In a uniquely large cohort of dementia patients, we examined the associations of cerebrospinal fluid biomarkers for Alzheimer's disease molecular pathology with clinical dementia diagnoses and disease severity. We cross-referenced the Swedish Dementia Registry with the clinical laboratory database at the Sahlgrenska University Hospital. The final data set consisted of 5676 unique subjects with a clinical dementia diagnosis and a complete set of measurements for cerebrospinal fluid amyloid-beta(1-42), total tau and phosphorylated tau. In cluster analysis, disregarding clinical diagnosis, the optimal natural separation of this data set was into two clusters, with the majority of patients with early onset Alzheimer's disease (75%) and late onset Alzheimer's disease (73%) assigned to one cluster and the patients with vascular dementia (91%), frontotemporal dementia (94%), Parkinson's disease dementia (94%) and dementia with Lewy bodies (87%) to the other cluster. Frontotemporal dementia had the highest cerebrospinal fluid levels of amyloid-beta(1-42) and the lowest levels of total tau and phosphorylated tau. The highest levels of total tau and phosphorylated tau and the lowest levels of amyloid-beta(1-42) and amyloid-beta(1-42):phosphorylated tau ratios were found in Alzheimer's disease. Low amyloid-beta(1-42), high total tau and high phosphorylated tau correlated with low Mini-Mental State Examination scores in Alzheimer's disease. In Parkinson's disease dementia and vascular dementia low cerebrospinal fluid amyloid-beta(1-42) was associated with low Mini-Mental State Examination score. In the vascular dementia, frontotemporal dementia, dementia with Lewy bodies and Parkinson's disease dementia groups 53%, 34%, 67% and 53% of the subjects, respectively had abnormal amyloid-beta(1-42) levels, 41%, 41%, 28% and 28% had abnormal total tau levels, and 29%, 28%, 25% and 19% had abnormal phosphorylated tau levels. Cerebrospinal fluid biomarkers were strongly associated with specific clinical dementia diagnoses with Alzheimer's disease and frontotemporal dementia showing the greatest difference in biomarker levels. In addition, cerebrospinal fluid amyloid-beta(1-42), total tau, phosphorylated tau and the amyloid-beta(1-42):phosphorylated tau ratio all correlated with poor cognitive performance in Alzheimer's disease, as did cerebrospinal fluid amyloid-beta(1-42) in Parkinson's disease dementia and vascular dementia. The results support the use of cerebrospinal fluid biomarkers to differentiate between dementias in clinical practice, and to estimate disease severity.
|
|
| 10. |
- Skillbäck, Tobias, et al.
(författare)
-
Cerebrospinal fluid tau and amyloid-β1-42 in patients with dementia.
- 2015
-
Ingår i: Brain : a journal of neurology. - : Oxford University Press (OUP). - 1460-2156 .- 0006-8950. ; 138:Pt 9, s. 2716-31
-
Tidskriftsartikel (refereegranskat)abstract
- Progressive cognitive decline in combination with a cerebrospinal fluid biomarker pattern of low levels of amyloid-β1-42 and high levels of total tau and phosphorylated tau is typical of Alzheimer's disease. However, several neurodegenerative disorders may overlap with Alzheimer's disease both in regards to clinical symptoms and neuropathology. In a uniquely large cohort of dementia patients, we examined the associations of cerebrospinal fluid biomarkers for Alzheimer's disease molecular pathology with clinical dementia diagnoses and disease severity. We cross-referenced the Swedish Dementia Registry with the clinical laboratory database at the Sahlgrenska University Hospital. The final data set consisted of 5676 unique subjects with a clinical dementia diagnosis and a complete set of measurements for cerebrospinal fluid amyloid-β1-42, total tau and phosphorylated tau. In cluster analysis, disregarding clinical diagnosis, the optimal natural separation of this data set was into two clusters, with the majority of patients with early onset Alzheimer's disease (75%) and late onset Alzheimer's disease (73%) assigned to one cluster and the patients with vascular dementia (91%), frontotemporal dementia (94%), Parkinson's disease dementia (94%) and dementia with Lewy bodies (87%) to the other cluster. Frontotemporal dementia had the highest cerebrospinal fluid levels of amyloid-β1-42 and the lowest levels of total tau and phosphorylated tau. The highest levels of total tau and phosphorylated tau and the lowest levels of amyloid-β1-42 and amyloid-β1-42:phosphorylated tau ratios were found in Alzheimer's disease. Low amyloid-β1-42, high total tau and high phosphorylated tau correlated with low Mini-Mental State Examination scores in Alzheimer's disease. In Parkinson's disease dementia and vascular dementia low cerebrospinal fluid amyloid-β1-42 was associated with low Mini-Mental State Examination score. In the vascular dementia, frontotemporal dementia, dementia with Lewy bodies and Parkinson's disease dementia groups 53%, 34%, 67% and 53% of the subjects, respectively had abnormal amyloid-β1-42 levels, 41%, 41%, 28% and 28% had abnormal total tau levels, and 29%, 28%, 25% and 19% had abnormal phosphorylated tau levels. Cerebrospinal fluid biomarkers were strongly associated with specific clinical dementia diagnoses with Alzheimer's disease and frontotemporal dementia showing the greatest difference in biomarker levels. In addition, cerebrospinal fluid amyloid-β1-42, total tau, phosphorylated tau and the amyloid-β1-42:phosphorylated tau ratio all correlated with poor cognitive performance in Alzheimer's disease, as did cerebrospinal fluid amyloid-β1-42 in Parkinson's disease dementia and vascular dementia. The results support the use of cerebrospinal fluid biomarkers to differentiate between dementias in clinical practice, and to estimate disease severity.
|
|
