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Increased contractility affects left ventricular kinetic energy in pulmonary hypertension
No full textPrecapillary pulmonary hypertension (PH) is characterized by increased pulmonary vascular resistance (PVR), with progressively altered right (RV) and left ventricular (LV) hemodynamics and function. Kinetic energy (KE) from 4D flow cardiovascular magnetic resonance (CMR) is a measure of intracardiac hemodynamics. In this observational case–control study, we investigate physiological mechanisms influencing RV-KE and LV-KE in PH. Twenty PH patients and 12 healthy controls underwent CMR including cine images and 4D flow. LV contractility was derived from noninvasive pressure-volume loops, and PVR from right heart catheterization. RV-KE and LV-KE were computed for systole, early and late diastolic filling, and indexed to stroke volume (SV). Systolic RV-KE did not differ between patients and controls. In patients, systolic RV-KE was associated with RV-SV but not with PVR, suggesting that the RV may still be able to compensate for the increased afterload. Systolic LV-KE indexed to LV-SV, LV contractility, and heart rate were all higher in patients than controls, suggesting sympathetic upregulation as a possible driving mechanism behind increased systolic LV-KE. LV contractility was negatively associated with systolic LV-KE and LV-SV. Late filling KE was increased in both ventricles in patients, suggesting an enhanced importance of the atrial kick to the filling of both ventricles
Identifying critical work-related characteristics in police roles : A comparative analysis using the O*NET framework
No full textPolicing roles require specific work-related characteristics (WRCs) critical for effective performance. This study identifies key WRCs for various roles within the Swedish Police—patrol officers, criminal investigators, Special Weapons and Tactics (SWAT) Teams, police chiefs, and negotiators—by analyzing data from 425 active-duty officers (30% response rate). We use the Occupational Information Network (O*NET) framework to assess WRCs in five domains and subsequently compare the identified profiles with the average U.S. workforce and U.S. law enforcement roles. Our findings indicate distinct differences in the WRC profiles required across various roles within the Swedish Police. Frontline roles, such as patrol officers and SWAT unit members, particularly emphasize physical strength, situational awareness, and social skills. At the same time, roles like negotiators and investigators show a higher demand for cognitive abilities and advanced interpersonal competencies. By comparing Swedish police roles with the general U.S. labor market and specific U.S. police functions, our results illustrate how sociocultural factors and organizational structures distinctly shape job demands. This highlights the importance of customizing and regularly updating work analyses to reflect rapid societal and technological changes, ensuring that recruitment, selection, and training processes align with current and future policing demands across national contexts
Research progress of transient absorption spectroscopy in solar energy conversion and utilization
No full textWith the development of ultrafast laser technology, time-resolved spectroscopy has become an essential tool to study the microscopic photophysical mechanisms on ultrafast time scales in the field of solar energy conversion and utilization. Transient absorption spectroscopy (TAS), as an essential technology for studying photoinduced ultrafast electron transfer and photo-induced carrier dynamics, has the unique advantage of revealing key dynamic processes, such as the generation, separation, transport, and recombination of photogenerated carriers. Focusing on light-to-chemical and light-to-electrical energy conversion, this review summarizes TAS applications in two primary solar energy conversion systems: photocatalysis and solar cells. Firstly, according to the different requirements of photocatalysis (emphasizing migration for surface reactions) and solar cells (highlighting interfacial carrier separation efficiency), we summarize design strategies and recent advances for enhancing carrier utilization from three perspectives: electron manipulation, hole manipulation and surface interfacial processes. Subsequently, special attention is given to how in situ spectroscopy elucidates the influence mechanisms of microscopic energy conversion processes and device performance under complex application scenarios involving photo-electro-thermal couplings. Finally, the forward-looking development direction of basic research in solar energy conversion and utilization is summarized, which provides theoretical support for rational design and performance optimization of solar energy conversion materials, reactions, and devices
Effects of salinisation on Cu-contaminated vineyard soils : Assessment of changes in microbial communities and resistance to salt, Cu, and antibiotics
No full textClimate change increases the risk of soil salinisation in Southern European vineyards. In this study, six of those soils were experimentally salinised, half of which were contaminated with Cu, a widely used fungicide. Changes in soil microbiota were assessed, including bacterial and fungal growth, respiration, carbon use efficiency calculation, and microbial community phospholipid fatty acids composition. The study also investigated whether salinisation induced a shift in the bacterial community toward increased tolerance to salt, Cu, and the antibiotics tetracycline and vancomycin. Results showed that experimental salinisation decreased bacterial growth and respiration, increased fungal growth, and limited fungal, bacterial, and microbial biomass. These effects were strongest in soils with high initial Cu content. In such soils, tolerance to salt stress was more pronounced, and salt-induced tolerance to vancomycin was observed. In contrast, tolerances to Cu and tetracycline antibiotic were not significantly increased by either Cu or salt. Subsequently, the soils underwent leaching, and analyses were repeated. Most changes in microbial parameters and tolerances were reversed, with soil texture being a particularly influential factor. However, leaching caused Cu tolerance in soils that had been salinised and had high Cu content to be greater than in soils that had not been salinised, regardless of whether they had high or low Cu content. After leaching, vancomycin tolerance also became positively correlated with soil Cu content in soils with low Cu levels. This preliminary study explored salinisation effects on soils, revealing possible bacterial resistance linked to past conditions and microbial shifts. Further research is needed to broaden the dataset and explore the underlying mechanisms and microbial species involved
Light Sensitive Bumblebee Species Are Associated With Forest Habitat and Forest-Dominated Landscapes
No full textWe investigate whether the eye parameter of bumblebees—a visual trait measuring the tradeoff between light sensitivity and visual resolution—is associated with: (i) local habitats, (ii) forest cover at the landscape scale (1 km radius), and (iii) the shade tolerance of the plants they forage on. The association of bumblebee species with local habitat and forest cover at the landscape scale was analyzed using generalized linear mixed models. We combined data from the Norwegian national bumblebee monitoring program with Corine CLC+ land cover and bumblebee functional traits: eye parameter and intertegular distance. These analyses were done at the species and community level. To determine whether bumblebee light sensitivity correlated with the shade tolerance of the plant they forage on, we combined bumblebee–plant interactions from a British database with a Swedish plant trait database. Our findings showed that bumblebee species with high light sensitivity were more common and abundant in forest habitats and areas with greater forest cover, while species with high visual resolution showed the opposite trend. This pattern was reflected at the community level, as indicated by the community-weighted mean of the eye parameter, which increased with forest cover and was higher in forest habitats. Furthermore, bumblebees with higher light sensitivity tended to forage on plants with greater shade tolerance. These results suggest that visual adaptations for light sensitivity contribute to shaping bumblebee species distributions across different scales. Our study underscores the importance of pollinator vision in understanding species niches and its value for species distribution modeling. Moreover, by relating pollinator visual abilities to plant niches for the first time, this study provides an important basis for future modeling of plant–pollinator interactions and targeted conservation measures for plants and pollinators in forested landscapes
Klimatanpassning av vägar i strandnära områden
No full textI den här rapporten ges en sammanfattning av en del av resultaten och metoderna från projektet Klimatanpassning av väg och järnväg i strandnära områden. Projektet har finansierats av Trafikverket och syftar till att studera klimatrisker för kustnära vägar med avseende på översvämnings- och erosionsprocesser, samt hur den riskutsatta infrastrukturen kan skyddas genom hållbara och naturanpassade metoder.Inom projektet har modellverktyget RoadRAT utvecklats som uppskattar sannolikheten för att kustnära vägar påverkas av översvämning, våguppspolning och erosion i dagens och framtidens klimat. RoadRAT har applicerats på kustvägen längs med Skånes sydkust. En del av den studerade vägsträckan utgörs av riksväg 9, som av Trafikverket utpekats som en av kustprocesser riskutsatt väg. Sannolikheten för påverkan av kustprocesser beräknades både i dagens klimat och för år 2050, 2100 och 2150 med hänsyn till olika framtida havsnivåhöjningsprognoser kopplade till olika utsläppsscenarier.Resultaten visar att under nuvarande förhållanden är påverkan av kustprocesser begränsad till några hundra meter av vägen. Men i framtiden kommer flera kilometer av vägen att vara exponerad och den största påverkan väntas bero på kusterosion. Exponeringen väntas öka med tiden och är starkt beroende av utsläppen av växthusgaser och deras påverkan på havsnivån. År 2150 beräknas 47 km av den totalt 89 km långa vägsträckan att vara påverkad av en eller flera kustprocesser. 11 km av vägen beräknas att ligga under 100-årsnivån för vattenstånd och 9 km vara påverkad av 100-årsnivån av våguppspolning. 42 km av vägen beräknas antingen att vara borteroderad till följd av långsiktig erosion eller inom påverkanszonen för stormerosion med 100-års återkomsttid. Beräkningsexemplet ovan är baserat på det högsta utsläppsscenariot från IPCC, SSP-5-8.5, vilket Trafikverket utgår ifrån i sitt klimatanpassningsarbete avseende havsnivåhöjningar.Vid någon tidpunkt i framtiden kommer höjningen av havsnivån sannolikt att tvinga fram en omlokalisering av vägen. Analysen av olika utsläppsscenarier visar dock att det år då det inte längre är möjligt att skydda vägen är osäkert och beror på samhällets förmåga att begränsa vår klimatpåverkan. Men analysen visar också att redan i ett kortare tidsperspektiv, under de kommande decennierna, kommer åtgärder att behövas för att reducera risken för skador på vägen till följd av kusterosion.Kustskyddsåtgärder delas traditionellt in i hårda och mjuka skydd. Konstruktioner av sten och betong brukar klassificeras som hårda skydd medan lösningar med sand och vegetation betraktas som mjuka. På senare år har även naturbaserade skydd och hybridskydd (kombination av hårt och mjukt) blivit allt vanligare. Som en del i det här projektet har ett så kallat hybridkustskydd analyserats i en fallstudie. Skyddet består av en betongmur och stenskoning som kombinerats med en strandfodring för att skydda en väg i Faxe Ladeplads på Själlands ostkust. Genom mätningar och modellstudier har kustskyddet effektivitet, samt strandfodringens utveckling utvärderats. Under studieperioden drabbades Faxe Ladeplads av stormen Babet (20-21 oktober 2023) som ledde till skador på muren och uppspolning på vägen. Strandfodringen reducerade vågpåverkan under stormen, men stenskoningens dimensionering var otillräcklig för att skydda vägen från våguppspolning. Strandfodringen i kombination med de hårda konstruktionerna hade utformats på ett sätt som avviker från den naturliga strandlinjeformen. Redan före stormen hade hybridskyddet försvagats på grund av omfördelning av sanden längs med och ut från kusten. Lärdomar från Faxe Ladeplads-projektet som skulle kunna överföras till Sveriges sydkust är att strandfodringen skapat positiva effekter som rekreationsmöjligheter inom området och sandackumulation nedströms skyddet. Men strandfodringen form och storlek behöver anpassas efter kustens naturliga form – inte följa vägens läge. Kontinuerlig uppföljning och underhållsfodring är nödvändig för att säkerställa att den dimensionerade skyddsnivån upprätthålls längs hela den fodrade sträckan
Emission of biogenic volatile organic compounds from intact & clearcut boreal forest : Multi-year observations of BVOC fluxes at a Swedish boreal forest and the ecosystem-scale BVOC impacts of clearcut forestry
No full textVegetation is the major source of volatile organic compounds (VOCs) in the atmosphere, which affect both air quality and climate. Long-term ecosystem-level data on biogenic VOC (BVOC) emissions, however, are limited. This is especially true regarding the impacts of landscape-scale disturbances like clear-cutting on the short-term and longer seasonal-scale emissions of boreal forests, particularly with respect to emissions in prior years.Presented in this PhD thesis document is an overview of BVOC concentration and flux measurements and results spanning several years, leading up to the summer 2022 clear-cutting of a boreal forest located at the ICOS (Integrated Carbon Observation System) and ACTRIS (Aerosol, Clouds, and Traces Gases Research Infrastructure) station Norunda (located at 60°05′N, 17°29′E, ca. 30 km north of Uppsala) in Sweden. This managed boreal forest, between 80 and 120 years old, primarily consisted of a mix of Scots pine (Pinus sylvestris) and Norway spruce (Picea abies). Beginning in summer 2020, BVOC mixing ratios were measured using a Vocus proton-transfer-reaction time-of-flight mass spectrometer (Vocus PTR-ToF-MS). These Vocus measurements (at 10 Hz) were collected at 35 m on the station flux tower to determine BVOC fluxes using the eddy-covariance method. During several intensive BVOC sampling periods in 2020 and 2022, hourly adsorbent samples were also collected, at 37 and 60 m, for subsequent automated-thermal-desorption gas-chromatography mass-spectrometry (ATD-GC-MS) analysis to determine compound-speciated BVOC concentrations. These samples were additionally used to estimate the changes in the fluxes of speciated monoterpene (MT) compounds using the surface-layer-gradient (SLG) and modified Bowen-ratio (MBR) methods. As part of the research to investigate boreal BVOC emissions, new software tools were also developed for processing high-frequency Vocus PTR-ToF-MS campaign datasets for the eddy-covariance analysis of long-term BVOC fluxes above the Norunda forest canopy. The results of this thesis indicate a large variety of VOC compounds being emitted by the forest system, including among terpenoids - e.g., isoprene, monoterpenes (MTs) and sesquiterpenes (SQTs). The most common MT compounds emitted were α-pinene and Δ3-carene. A seasonal investigation of the vertical distribution of BVOC sources and sinks within and below the intact Norunda forest canopy also found a significant proportion of the forest’s MT emission in autumn originating from the forest floor. During the 2022 clearcut, MT emissions increased by 1-2 orders of magnitude during active-cutting, with persisting MT emission increases from clearcut residue which continued for several months. In comparison, many BVOCs lacking storage reservoirs in plant tissues (e.g., isoprene) were relatively unaffected by active-cutting. Fluxes and the mixture of speciated MT compounds observed before, during, and post-cut are compared, and the additional total and speciated MT emissions due to clear-cutting are estimated. For context, in Sweden 69% of total land cover is forest, of which 84% is productive forest for clear-cut forestry (~58% of total land cover). From Swedish forestry information of yearly absolute timber removal and on-site residue volumes following typical clearcuts, these results show that current Swedish boreal forest MT emission inventory estimates may be significantly underestimated