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While a significant influence of volcanic activity on Holocene climate is well-established, an equally prominent role of major eruptions in the climate variability and regime shifts during the Quaternary glacial cycles has been suggested. Previous statistical assessments of this were challenged by inaccurate synchronization of large volcanic eruptions to changes in past climate. Here, this is alleviated by combining a new record of bipolar volcanism from Greenland and Antarctic ice cores with records of abrupt climate change derived from the same ice cores. We show that bipolar volcanic eruptions occurred significantly more frequently than expected by chance just before the onset of Dansgaard–Oeschger events, which are the most prominent large-scale abrupt climate changes in the last glacial period. Out of 20 abrupt warming events in the 12–60 ka period, 5 (7) occur within 20 (50) years after a bipolar eruption. We hypothesize that this may be a result of the direct influence of volcanic cooling on the Atlantic meridional overturning circulation, which is widely regarded as the main climate subsystem involved in Dansgaard–Oeschger cycles. Transitions from a weak to a strong circulation mode may be triggered by cooling in the North Atlantic given that the circulation is close to a stability threshold. We illustrate this suggestion by simulations with an ocean-only general circulation model forced by short-term volcanic cooling. The analysis presented suggests that large eruptions may act as short-term triggers for large-scale abrupt climate change and may explain some of the variability of Dansgaard–Oeschger cycles. While we argue that the bipolar catalogue used here covers a sufficiently large portion of the eruptions with the strongest global climate impact, volcanic events restricted to either the Northern or Southern Hemisphere may likewise contribute to abrupt climate change.

Between 15 and 27 kyr b2k (thousands of years before 2000 CE) during the last glacial, Greenland experienced a prolonged cold stadial phase, interrupted by two short-lived warm interstadials. Greenland ice-core calcium data show two periods, preceding the interstadials, of anomalously high atmospheric dust loading, the origin of which is not well understood. At approximately the same time as the Greenland dust peaks, the Chinese Hulu Cave speleothems exhibit a climatic signal suggested to be a response to Heinrich Event 2, a period of enhanced ice-rafted debris deposition in the North Atlantic. In the climatic signal of Antarctic ice cores, moreover, a relative warming occurs between 23 and 24.5 kyr b2k that is generally interpreted as a counterpart to a cool climate phase in the Northern Hemisphere. Proposed centennial-scale offsets between the polar ice-core timescales and the speleothem timescale hamper the precise reconstruction of the global sequence of these climatic events. Here, we examine two new 10Be datasets from Greenland and Antarctic ice cores to test the agreement between different timescales, by taking advantage of the globally synchronous cosmogenic radionuclide production rates. Evidence of an event similar to the Maunder Solar Minimum is found in the new 10Be datasets, supported by lower-resolution radionuclide data from Greenland and 14C in the Hulu Cave speleothem, representing a good synchronization candidate at around 22 kyr b2k. By matching the respective 10Be data, we determine the offset between the Greenland ice-core chronology, GICC05, and the Antarctic chronology for the West Antarctic Ice Sheet Divide ice core (WDC), WD2014, to be 125 ± 40 years. Furthermore, via radionuclide wiggle-matching, we determine the offset between the Hulu speleothem and ice-core timescales to be 375 years for GICC05 (75–625 years at 68 % confidence) and 225 years for WD2014 (−25–425 years at 68 % confidence). The rather wide uncertainties are intrinsic to the wiggle-matching algorithm and the limitations set by data resolution. The undercounting of annual layers in GICC05 inferred from the offset is hypothesized to have been caused by a combination of underdetected annual layers, especially during periods with low winter precipitation, and misinterpreted unusual patterns in the annual signal during the extremely cold period often referred to as Heinrich Stadial 1.

Action-äventyrspels immersion och användbarhet påverkas av deras UI:s form och design. Tidigare forskning visar att diegetiskt UI bidrar till immersion men forskningen saknar insikter om hur olika varianter av UI påverkar spelens användbarhet. Data insamlad från test av spelares upplevelse av immersion och användbarhet i tre olika artefakter – designade med icke-diegetiskt-,meta-perceptivt- och diegetiskt UI – visar att när diegesen ökar så ökar även immersionen, samtidigt som användbarheten sjunker. Eftersom studiens resultat är baserade på tre artefakter som bara använder sig av en variant av UI så visar den inte slutsatser om hur kombinationer av UI kan främja användbarhet och immersion, vilket uppmanar till framtida studier. Studiens resultat uppmanar också till framtida studier i andra genrer av spel.

The Younger Toba Tuff eruption ∼74 ka ago in Indonesia, is among the largest known supereruptions in the Quaternary and its potential impact on the climate system and human evolution remains controversially debated. The eruption is dated radiometrically to 73.88 ± 0.32 ka (1σ, Storey et al., 2012) and it occurred at the abrupt cooling transition from Greenland Interstadial 20 to Greenland Stadial 20. The precise stratigraphic position of volcanic fallout detected in ice cores from both polar ice sheets has previously been narrowed down to four potential candidates. Here, we compile all available Greenland and Antarctic sulfate records, together with electrical conductivity records and recently obtained sulfur isotope records to identify, quantify and characterize these Toba candidates in terms of their likely latitudinal position of eruption, sulfur emission strength and radiative forcing. We identify that the youngest event of the four candidates is composed of two separate eruptions, both likely located in the extra-tropical Northern Hemisphere. We deem the two older events unlikely candidates for the Toba eruption because of their limited sulfur emission strengths. The second youngest event has the largest sulfur output of the Toba candidates, and it is also larger than any other volcanic event identified in ice core records over the last 60 kyr. Comparable amounts of sulfate deposits in Greenland and Antarctica strongly suggest a tropical source. We thus propose the second youngest event (74,156 years before 2000 CE) to be most likely associated with the Toba eruption. The estimated stratospheric sulfate loading of the proposed Toba eruption is 535 ± 96 Tg, which is 3 times that of Samalas 1258 CE, 6 times that of Tambora (1815) CE and 20 times that of Pinatubo (1991) CE. We derive the continuous time-series of volcanic sulfate deposition, sulfur emission strength and radiative forcing over the 74.8–73.8 ka time window, suitable for conducting experiments with climate models that either require prescribed forcing field or interactively reproduce aerosol processes. We estimate the cumulative volcanic sulfur emission strength and the radiative forcing of the two younger events and they are found to be much stronger than those at the onset of the Younger Dryas and those preceding the Little Ice Age. Stacked Greenland water isotope records show an accelerated transition trend and abrupt shift after the proposed Toba eruption and suggest that the Greenland moisture source moved southward shortly after the Toba eruption. The Toba eruption may thus have an amplifying effect on the cooling transition leading to Greenland Stadial 20.

Background: Methoxyflurane (MTX) is an inhalation agent that has several potential benefits for limiting various types of pain in ambulance care. Aim: To elucidate how ambulance nurses experience the characteristics of MTX in an ambulance care setting. Method: This cross-sectional study applied a mixed-methods approach, using a questionnaire together with complementary interviews. The questionnaire survey was analyzed using descriptive statistics (10-point Likert scale and question index values [Q-IV], range: 0-1.0). The interviews were analyzed using directed content analysis. Study results were reported following the STROBE statement. Results: The ambulance nurses' overall general satisfaction with the MTX concept had a median of 7.0 (IQR 5-8), corresponding to a mean Q-IV of 0.84 (very good experience). The qualitative part was divided into three categories: sense of security, patient participation, and general usefulness. The results revealed varying experiences of usefulness, including pain-relieving effect and the possibility of patient participation. The perceived strong odor of MTX seemed to concern the ambulance nurses and their patients. Conclusion: In general, MTX was experienced as a safe and effective analgesic. However, the experiences of the overall usefulness varied, particularly since the product had a perceived strong odor. Increasing knowledge of using MTX, could likely increase the overall usefulness.

A 45-year-old female dialysis patient with sudden onset of severe pain in the left shoulder and chest was referred for computed tomography of her left arm and thoracic veins. The computed tomography venography revealed 2 completely occluded venous grafts and 2 pronounced stenoses of the subclavian vein. By using a dual injection of diluted and undiluted contrast medium, artifact-free visualization of arteriovenous fistula, arm veins and adequate enhancement of thoracic veins were obtained. Keywords: Computed tomography, Arteriovenous fistula, Contrast agents-intravenous

Purpose This study aimed to describe extended collaboration in situations when an ambulance was called, as experienced by older patients, a significant other, and ambulance- and primary healthcare (PHC) centre personnel. Methods The study used a phenomenological reflective lifeworld research (RLR) approach. Participants included in three specific situations with extended collaboration were interviewed: three older patients, one significant other, three ambulance personnel and four personnel at the PHC centre. The transcribed interviews were analysed for meanings of the phenomenon. Results The extended collaboration means that decisions were supported through dialogue by bridging knowledge spaces between person, within-team and across-team levels. Through dialogue experience and knowledge were shared and certainty in decisions was increased. The extended collaboration was built on trust, responsibility taken, shared and entrusted, and the common goal of adapted care for the unique patient. A need for further improvement and transparency was elucidated. Conclusions The difficulty of making care decisions stresses the importance of available extended collaboration based on the dialogue between patients, significant others, and ambulance- and PHC centre personnel to increase certainty in decisions. Collaboration further requires respectful encounters, trust, responsibility and a common goal of adapting the care for the unique patient.

Sedan Försvarsmakten påbörjade sin akademisering av officerskåren, dels med officersprogrammet på Försvarshögskolan och med ett uppdragsutbildningsprogram i samarbete med bland annat Halmstad universitet så har det skrivits och producerats många uppsatser med fokus på plutonchefernas situation. I de studierna har huvudsakligen plutonchefernas chefer eller andra i deras omgivning intervjuats. Den här uppsatsen bidrar med perspektivet från plutoncheferna själva, de unga officerare och specialistofficerare som är mitt i lösandet av befattningen. Syftet med studien är att utreda och skapa förståelse för de unga plutonchefernas situation. Diskussionen förs ur perspektivet vad organisationen, Försvarsmakten, kan göra för att skapa så bra förutsättningar som möjligt för plutoncheferna att lösa sin arbetsuppgift. Den här uppsatsen bekräftar bilden av vad tidigare studier visar och det råder en samsyn om hur komplex situationen är för nytillträdda chefer. Studiens resultat visar att de unga har drivkraft och ambition att lösa uppgiften som plutonchef men att det saknas viss kunskap. Resultaten visar även att befattningens innebörd är otydlig i hela organisationen och Försvarsmakten skulle behöva tydliggöra produktionsorganisationen i vardagen och överväga att definiera innebörden och förväntningarna av att vara plutonchef i tre perspektiv: plutonchef i grundutbildning, plutonchef för kontinuerligt anställda soldater (GSS/K) och krigsplutonchef, det vill säga plutonchef i krigsorganisationen som är under utbildning och den som truppför enheten vid övning, kris eller krig. Studien visar även att organisationen är medveten om vilken kunskap och erfarenhet de unga har och inte har för att lösa befattningen som plutonchef när de examineras men att planen för att utveckla den kunskap som krävs behöver överses. Detta ställer krav på hur stödet utformas kring de unga cheferna i form av ett genomtänkt arbetslag samt stöd och handledning från plutonchefernas chefer, i normala fall kompanicheferna. Since the Swedish Armed Forces began to academies the officers' corps, the officer program at the Swedish Defence University and also during complementary education program in collaboration with, among others, Halmstad University, many essays have been written focusing on the situation of platoon commanders. In those studies mostly the platoon commanders’ superiors or others around them have been interviewed. This paper adds the perspective of the platoon commanders themselves, the young officers and non-commissioned officers who are in the midst of resolving the position. The purpose of the study is to investigate and create an understanding for the situation of the young platoon commanders. The discussion is based on what the organization, the Swedish Armed Forces, can do to create the best possible conditions for the platoon commanders to solve their task. This paper confirms the picture of what previous studies show and there is a consensus on how complex the situation is for newly appointed platoon commanders. The results of the study show that the young have the drive and ambition to solve the task as platoon commander but that some knowledge is lacking. The result also shows that the definition of the position is unclear throughout the organization and the Swedish Armed Forces would need to clarify the organization used to produce units in basic training and consider defining the meaning and expectations of being platoon commander in three perspectives: platoon commander in basic training, platoon commander for employed soldiers and pluton commander in the organization during war, which is the one who commands the unit in training, crisis or war. The study also shows that the organization is aware of the knowledge and experience that the young have, and not have, solving the position as platoon commander when they are examined, but that the plan to develop the necessary knowledge needs to be reviewed more carefully. This places demands on how the support is designed around the young commanders in the form of a well-thought-out team as well as support and supervision from the platoon commanders’ superiors, normally the company commanders.

Näringslivets omställning med investeringar som bidrar till miljömålen och minskad klimatpåverkan sker nu i snabb takt. I Norrbottens län och Västerbottens län har ett antal industriprojekt på senare tid aktualiserats, som kan ge ett väsentligt bidrag till denna gröna omställning. För att industrisatsningarna ska kunna genomföras, och för att de potentialer som finns ska kunna effektueras, behöver ett antal viktiga åtgärder i transportinfrastrukturen prioriteras och tidigareläggas. De företagsetableringar och företagsexpansioner som genomförs eller planeras i Norrbottens län och Västerbottens län kommer att ställa nya krav på transportinfrastrukturen. Regeringen har gett Trafikverket i uppdrag att analysera vilken påverkan detta får för transportinfrastrukturen samt vilka behov av åtgärder som kan väntas uppstå med anledning av denna samhällsomställning.