Mänsklig påverkan på mindre vattendrag i skogslandskapet : en inventering av vägtrummor och skyddszoner kring dessa i Uppsala län och norra Västmanlands län

Interference in an ecosystem means a disturbance. When harvesting, forest roads have to be build to cope with heavy duty vehicles. Crossing brooks can not always be avoided. In this case bridges or culverts have to be built. There are many different kinds of culverts and depending on what type you choose and how you place the culvert, the watercourse and the water organisms can be harmed in different ways. If you choose the best alternative and place the culvert correctly, migration of aquatic living organisms is possible. Migration barriers can be high velocity in the culvert, large jumping height from the brook or too small water depth close to the culvert. Forestry is carried out as effectively as possible. This can result in damaged protection zones along the brooks. To leave protection zones means incurred costs. Furthermore, it takes time to consider which trees to leave and the harvester may not see the watercourse or may lack knowledge about the value of protection zones along streams. I inventoried 118 culverts. Johan Spens at the Department for Aquaculture at SLU in Umeå has developed a calculating model, the ecohydraulic model, which can predict a culverts function and determine whether it is a possible migration barrier. I tested the model by comparing it with two other models, System Aqua developed by the Swedish Environmental Protection Agency and guidelines developed by the Swedish Fisheries Agency. I could test all three different models at 21 culverts, comparing the results in respect of whether the culverts were migration barriers. The ecohydraulic model calculated that 17 culverts was a migration barrier, the Fishery Agency's guidelines resulted in 18 barriers and System Aqua in 10. In comparison to System Aqua and the Swedish Fisheries Agency guidelines, I conclude that the ecohydraulic model provides a realistic evaluation of the culvert function. It also takes into consideration seasonal variations in water levels, thus providing information on whether the culvert is under-dimensioned. Furthermore, the model is easy to use for persons without aquatic – ecological competence.Varje ingrepp i ett ekosystem innebär en störning. När avverkningar skall göras måste det byggas hållbara vägar för att göra framkomligheten för tunga fordon möjligt. Det går inte alltid att undvika att vattendrag korsas. Då läggs oftast vägtrummor i vattendraget. Det finns många olika typer av vägtrummor och beroende på vilken typ man väljer och hur man placerar trumman, påverkas vattendraget och de vattenlevande organismerna olika mycket. Ju bättre trumma man väljer desto mindre blir störningarna och vandringen av vattenorganismer äventyras inte. Möjliga vandringshinder kan vara för hög hastighet av genomflödande vatten, för hög hopphöjd (avståndet mellan trummans nedre kant och bäckytan) och för litet ansatsdjup (vattendjupet i bäcken under trumman). Dagens skogsbruk bedrivs så effektivt som möjligt. Detta kan resultera i att skyddszoner mot de mindre vattendragen inte lämnas. Det kan bero på flera olika faktorer, bl.a. att det är resurskrävande (det tar tid att planera vad som skall lämnas och tid är pengar), att markägaren förlorar pengar (timmervärdet går förlorat), att skogsarbetaren inte ser vattendragen och kan därmed inte lämna någon skyddszon eller brist på kunskap om värdet av skyddszoner. Jag inventerade sammanlagt 118 vägtrummor. Johan Spens vid Institutionen för vattenbruk vid SLU i Umeå har utvecklat en beräkningsmodell, den ekohydrauliska modellen, som skall kunna förutsäga om en vägtrumma är ett möjligt vandringshinder. Jag testade modellen genom att jämföra den med två andra bedömningsmodeller, System Aqua från Naturvårdsverket och Fiskeriverkets riktlinjer. Vid 21 av de inventerade 118 trummorna kunde jag testa alla tre modeller och jämföra resultaten med varandra. Den ekohydrauliska modellen beräknade att 17 av dessa vägtrummor är vandringshinder vid någon tid på året. Enligt Fiskeriverkets riktlinjer är 18 vandringshinder och enligt System Aqua är 10 vandringshinder för fisk. Till skillnad från System Aqua och Fiskeriverkets riktlinjer bedömer jag att den ekohydrauliska modellen ger en realistisk bedömning av vägtrummans funktion. Den tar också hänsyn till olika vattenflöden under året och ger därför svar på om trumman är underdimensionerad. Samtidigt är den lätt att använda också för personer som inte har akvatiska/ekologiska förkunskaper

Ambulatory Hypertension Subtypes and 24-Hour Systolic and Diastolic Blood Pressure as Distinct Outcome Predictors in 8341 Untreated People Recruited From 12 Populations

Background—Data on risk associated with 24-hour ambulatory diastolic (DBP24) versus systolic (SBP24) blood pressure are scarce. Methods and Results—We recorded 24-hour blood pressure and health outcomes in 8341 untreated people (mean age, 50.8 years; 46.6% women) randomly recruited from 12 populations. We computed hazard ratios (HRs) using multivariable-adjusted Cox regression. Over 11.2 years (median), 927 (11.1%) participants died, 356 (4.3%) from cardiovascular causes, and 744 (8.9%) experienced a fatal or nonfatal cardiovascular event. Isolated diastolic hypertension (DBP24≥80 mm Hg) did not increase the risk of total mortality, cardiovascular mortality, or stroke (HRs≤1.54; P≥0.18), but was associated with a higher risk of fatal combined with nonfatal cardiovascular, cardiac, or coronary events (HRs≥1.75; P≤0.0054). Isolated systolic hypertension (SBP24≥130 mm Hg) and mixed diastolic plus systolic hypertension were associated with increased risks of all aforementioned end points (P≤0.0012). Below age 50, DBP24 was the main driver of risk, reaching significance for total (HR for 1-SD increase, 2.05; P=0.0039) and cardiovascular mortality (HR, 4.07; P=0.0032) and for all cardiovascular end points combined (HR, 1.74; P=0.039) with a nonsignificant contribution of SBP24 (HR≤0.92; P≥0.068); above age 50, SBP24 predicted all end points (HR≥1.19; P≤0.0002) with a nonsignificant contribution of DBP24 (0.96≤HR≤1.14; P≥0.10). The interactions of age with SBP24 and DBP24 were significant for all cardiovascular and coronary events (P≤0.043). Conclusions—The risks conferred by DBP24 and SBP24 are age dependent. DBP24 and isolated diastolic hypertension drive coronary complications below age 50, whereas above age 50 SBP24 and isolated systolic and mixed hypertension are the predominant risk factors

Outcome-Driven Thresholds for Ambulatory Pulse Pressure in 9938 People Recruited from 11 Populations

Evidence-based thresholds for risk stratification based on pulse pressure (PP) are currently unavailable. To derive outcome-driven thresholds for the 24–h ambulatory PP, we analyzed 9938 people randomly recruited from 11 populations (47.3% women). After age stratification (≥60 years) and using average risk as reference, we computed multivariable-adjusted hazard ratios (HRs) to assess risk by tenths of the PP distribution or risk associated with stepwise increasing (+1 mm Hg) PP levels. All adjustments included mean arterial pressure. Among 6028 younger participants (68,853 person-years), the risk of cardiovascular (HR, 1.58; P=0.011) or cardiac (HR, 1.52; P=0.056) events increased only in the top PP tenth (mean, 60.6 mm Hg). Using stepwise increasing PP levels, the lower boundary of the 95% confidence interval of the successive thresholds did not cross unity. Among 3910 older participants (39,923 person-years), risk increased (P≤0.028) in the top PP tenth (mean, 76.1 mm Hg). HRs were 1.30 and 1.62 for total and cardiovascular mortality, and 1.52, 1.69 and 1.40 for all cardiovascular, cardiac and cerebrovascular events. The lower boundary of the 95% confidence interval of the HRs associated with stepwise increasing PP levels crossed unity at 64 mm Hg. While accounting for all covariables, the top tenth of PP contributed less than 0.3% (generalized R2 statistic) to the overall risk among elderly. Thus, in randomly recruited people, ambulatory PP does not add to risk stratification below age 60; in the elderly, PP is a weak risk factor with levels below 64 mm Hg probably being innocuous

Opposing Age-Related Trends in Absolute and Relative Risk of Adverse Health Outcomes Associated with Out-of-Office Blood Pressure

Participant-level meta-analyses assessed the age-specific relevance of office blood pressure to cardiovascular complications, but this information is lacking for out-of-office blood pressure. At baseline, daytime ambulatory (n=12 624) or home (n=5297) blood pressure were measured in 17 921 participants (51.3% women; mean age, 54.2 years) from 17 population cohorts. Subsequently, mortality and cardiovascular events were recorded. Using multivariable Cox regression, floating absolute risk was computed across 4 age bands (≤60, 61-70, 71-80, and \u3e80 years). Over 236 491 person-years, 3855 people died and 2942 cardiovascular events occurred. From levels as low as 110/65 mm Hg, risk log-linearly increased with higher out-of-office systolic/diastolic blood pressure. From the youngest to the oldest age group, rates expressed per 1000 person-years increased (P\u3c0.001) from 4.4 (95% CI, 4.0-4.7) to 86.3 (76.1-96.5) for all-cause mortality and from 4.1 (3.9-4.6) to 59.8 (51.0-68.7) for cardiovascular events, whereas hazard ratios per 20-mm Hg increment in systolic out-of-office blood pressure decreased (P≤0.0033) from 1.42 (1.19-1.69) to 1.09 (1.05-1.12) and from 1.70 (1.51-1.92) to 1.12 (1.07-1.17), respectively. These age-related trends were similar for out-of-office diastolic pressure and were generally consistent in both sexes and across ethnicities. In conclusion, adverse outcomes were directly associated with out-of-office blood pressure in adults. At young age, the absolute risk associated with out-of-office blood pressure was low, but relative risk high, whereas with advancing age relative risk decreased and absolute risk increased. These observations highlight the need of a lifecourse approach for the management of hypertension

Mortality, outcomes, costs, and use of medicines following a first heart failure hospitalization: EVOLUTION HF

Background: There are few contemporary data on outcomes, costs, and treatment following a hospitalization for heart failure (hHF) in epidemiologically representative cohorts. Objectives: The study sought to describe rehospitalizations, hospitalization costs, use of guideline-directed medical therapy (GDMT) (renin-angiotensin system inhibitors, sacubitril/valsartan, beta-blockers, mineralocorticoid receptor antagonists, and sodium-glucose cotransporter-2 inhibitors), and mortality after hHF. Methods: EVOLUTION HF (Utilization of Dapagliflozin and Other Guideline Directed Medical Therapies in Heart Failure Patients: A Multinational Observational Study Based on Secondary Data) is an observational, longitudinal cohort study using data from electronic health records or claims data sources in Japan, Sweden, the United Kingdom, and the United States. Adults with a first hHF discharge between 2018 and 2022 were included. One-year event rates per 100 patient-years (ERs) for death and rehospitalizations (with a primary diagnosis of heart failure (HF), chronic kidney disease [CKD], myocardial infarction, stroke, or peripheral artery disease) were calculated. Hospital health care costs were cumulatively summarized. Cumulative GDMT use was assessed using Kaplan-Meier estimates. Results: Of 263,525 patients, 28% died within the first year post-hHF (ER: 28.4 [95% CI: 27.0-29.9]). Rehospitalizations were mainly driven by HF (ER: 13.6 [95% CI: 9.8-17.4]) and CKD (ER: 4.5 [95% CI: 3.6-5.3]), whereas the ERs for myocardial infarction, stroke, and peripheral artery disease were lower. Health care costs were predominantly driven by HF and CKD. Between 2020 and 2022, use of renin-angiotensin system inhibitors, sacubitril/valsartan, beta-blockers, and mineralocorticoid receptor antagonists changed little, whereas uptake of sodium-glucose cotransporter-2 inhibitors increased 2- to 7-fold. Conclusions: Incident post-hHF rehospitalization risks and costs were high, and GDMT use changed little in the year following discharge, highlighting the need to consider earlier and greater implementation of GDMT to manage risks and reduce costs

Lower Risk of Heart Failure and Death in Patients Initiated on Sodium-Glucose Cotransporter-2 Inhibitors Versus Other Glucose-Lowering DrugsClinical Perspective: The CVD-REAL Study (Comparative Effectiveness of Cardiovascular Outcomes in New Users of Sodium-Glucose Cotransporter-2 Inhibitors)

Reduction in cardiovascular death and hospitalization for heart failure (HHF) was recently reported with the sodium-glucose cotransporter-2 inhibitor (SGLT-2i) empagliflozin in patients with type 2 diabetes mellitus who have atherosclerotic cardiovascular disease. We compared HHF and death in patients newly initiated on any SGLT-2i versus other glucose-lowering drugs in 6 countries to determine if these benefits are seen in real-world practice and across SGLT-2i class

Подготовка ИТ-консультантов в российских вузах в разрезе проблематики консалтинга

Differences in clinical effectiveness between angiotensin-converting enzyme inhibitors (ACEis) and angiotensin receptor blockers (ARBs) in the primary treatment of hypertension are unknown. The aim of this retrospective cohort study was to assess the prevention of type 2 diabetes and cardiovascular disease (CVD) in patients treated with ARBs or ACEis. Patients initiated on enalapril or candesartan treatment in 71 Swedish primary care centers between 1999 and 2007 were included. Medical records data were extracted and linked with nationwide hospital discharge and cause of death registers. The 11 725 patients initiated on enalapril and 4265 on candesartan had similar baseline characteristics. During a mean follow-up of 1.84 years, 36 482 patient-years, the risk of new diabetes onset was lower in the candesartan group (hazard ratio (HR) 0.81, 95% confidence interval (CI) 0.69-0.96, P = 0.01) compared with the enalapril group. No difference between the groups was observed in CVD risk (HR 0.99, 95% CI 0.87-1.13, P = 0.86). More patients discontinued treatment in the enalapril group (38.1%) vs the candesartan group (27.2%). In a clinical setting, patients initiated on candesartan treatment had a lower risk of new-onset type 2 diabetes and lower rates of drug discontinuation compared with patients initiated on enalapril. No differences in CVD risk were observed

Opposing Age-Related Trends in Absolute and Relative Risk of Adverse Health Outcomes Associated With Out-of-Office Blood Pressure

Participant-level meta-analyses assessed the age-specific relevance of office blood pressure to cardiovascular complications, but this information is lacking for out-of-office blood pressure. At baseline, daytime ambulatory (n=12 624) or home (n=5297) blood pressure were measured in 17 921 participants (51.3% women; mean age, 54.2 years) from 17 population cohorts. Subsequently, mortality and cardiovascular events were recorded. Using multivariable Cox regression, floating absolute risk was computed across 4 age bands (80 years). Over 236 491 person-years, 3855 people died and 2942 cardiovascular events occurred. From levels as low as 110/65 mm Hg, risk log-linearly increased with higher out-of-office systolic/diastolic blood pressure. From the youngest to the oldest age group, rates expressed per 1000 person-years increased (P<0.001) from 4.4 (95% CI, 4.0-4.7) to 86.3 (76.1-96.5) for all-cause mortality and from 4.1 (3.9-4.6) to 59.8 (51.0-68.7) for cardiovascular events, whereas hazard ratios per 20-mm Hg increment in systolic out-of-office blood pressure decreased (P <= 0.0033) from 1.42 (1.19-1.69) to 1.09 (1.05-1.12) and from 1.70 (1.51-1.92) to 1.12 (1.07-1.17), respectively. These age-related trends were similar for out-of-office diastolic pressure and were generally consistent in both sexes and across ethnicities. In conclusion, adverse outcomes were directly associated with out-of-office blood pressure in adults. At young age, the absolute risk associated with out-of-office blood pressure was low, but relative risk high, whereas with advancing age relative risk decreased and absolute risk increased. These observations highlight the need of a lifecourse approach for the management of hypertension

Grid Scale Storage Placement In Power Systems

The increasing amount of renewable energy sources is applying more and more pressure on today’s power system. Additionally, plannable sources of energy, which are mostly non-renewable, are being decommissioned at a high rate to combat climate change. The decommissioning of non-renewable producers and the increasing number of intermittent sources of energy are causing an increasingly volatile power system. In addition to the lack of plannable production, the inertia from synchronously rotating machines is decreasing due to the lack of contribution from renewable sources. The inertia of a power system assists in slowing down large frequency changes. When a notably large difference between production and consumption occurs in a power system with low inertia, components which can quickly counteract these effects by supplying the system with active power, are needed. The low inertia can also cause problems to the synchronicity of the synchronously rotating machines in the system, namely the rotor angle stability. A lack of rotorangle stability can cause the synchronicity of the synchronously rotating machines to be questioned. Fast frequency response units supply the power system with active power for a short period of time to reduce the rate of change of frequency and frequency deviation, which in turn allows the self-regulating units more time to adjust their production. Furthermore, these units can improve rotor angle stability. Such units can consist of batteries which are both serially and parallel connected with their associated control unit. This thesis aims to, with the help of the power system analysis program PowerFactory, and its associated dynamic simulation tools, formulate a methodology which can be used in power system models to locate the best placement for fast frequency response units. The results show that the formulated methodology can be used to find the best position of fast frequency response units for frequency deviation-, rate of change of frequency- and rotor angle stability support