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Proteorhodopsin insights into the molecular mechanism of vectorial proton transport
No full textBacterial proton pumps, proteorhodopsins (PRs), are a major group of light-driven membrane proteins found in marine bacteria. They are functionally and structurally distinct from archaeal and eukaryotic proton pumps. To elucidate the proton transfer mechanism by PRs and understand the differences to nonbacterial pumps on a molecular level, high-resolution structures of PRs' functional states are needed. In this work, we have determined atomic-resolution structures of MAR, a PR from marine actinobacteria, in various functional states, notably the challenging late O intermediate state. These data and information from recent atomic-resolution structures on an archaeal outward proton pump bacteriorhodopsin and bacterial inward proton pump xenorhodopsin allow for deducing key universal elements for light-driven proton pumping. First, long hydrogen-bonded chains characterize proton pathways. Second, short hydrogen bonds allow proton storage and inhibit their backflow. Last, the retinal Schiff base is the active proton donor and acceptor to and from hydrogen-bonded chains
Negative-Ion Formation upon Soft X-ray Photoexcitation of 2-Propanol
No full textThis study investigates the formation of negative ion fragments from gas-phase 2-propanol molecules after interaction with soft X-rays near the O K-edge. The experiment was performed by detecting negative and positive ions in coincidence with time-of-flight spectrometry. The analysis of two- and three-ion coincidence data revealed that nine different anions were produced: H-, C-, CH-, CH2 -, O-, OH-, C2 -, C2H-, and C3 -. For all anions, the most common three-ion events were those involving two protons. The results highlight the sensitivity of negative-ion/positive-ion coincidence spectroscopy and provide new insight into the fragmentation processes of organic molecules under soft X-ray excitation
An emotional journey and new everyday challenges : A literature review on parents' experiences of having a child with type 1 diabetes
No full textBakgrund: Diabetes typ 1 är en autoimmun sjukdom som ofta debuterar i barndomen vilket kräver livslång och komplex behandling. Sjukdomen påverkar inte bara barnet utan hela familjen och föräldrarna får ta stort ansvar för barnets egenvård. Denna livsomställning kan leda till emotionell påfrestning och påverkat välmående. För att sjuksköterskor ska kunna ge förbättrat stöd behövs ökad kunskap om föräldrars erfarenheter. Syfte: Syftet med denna litteraturstudie var att beskriva föräldrars erfarenheter av att ha barn med diabetes typ 1. Metod: Litteraturstudien baserades på nio kvalitativa artiklar som valdes genom sökningar i databaserna PubMed, CINAHL och PsycInfo. Artiklarna kvalitetsgranskades och analyserades utifrån Fribergs femstegsmodell. Resultat: Resultatet från analysen sammanställdes i tre kategorier: En ny livssituation, Förändrade relationer och Behov av stöd med tillhörande sex underkategorier. Konklusion: Att vara förälder till ett barn med diabetes typ 1 innebär en livsomställning vilket kan bidra till stress, oro och påverkan på relationer. Föräldrarna bär ett stort ansvar för barnets egenvård. Sjuksköterskan bör erbjuda empati, tydlig information och kontinuerligt stöd. Att minska föräldrarnas belastning och stärka deras välbefinnande kan hjälpa dem att stödja barnet på bästa sätt.Background: Type 1 diabetes is an autoimmune disease that often manifests in childhood and requires lifelong and complex treatment. The condition affects not only the child but the entire family, with parents bearing significant responsibility for the child’s self-care. This life transition can result in emotional strain and reduced well-being. To provide improved support, nurses need a deeper understanding of parents’ experiences. Aim: The aim was to describe parents’ experiences of having a child with type 1 diabetes. Methods: The literature review is based on nine qualitative articles selected through searches in the databases PubMed, CINAHL, and PsycInfo. The articles were quality reviewed and analyzed using Friberg’s five-step model. Results: The results from the analysis were compiled into three categories: A new life situation, Changed relationships, and The need for support, with six associated subcategories. Conclusion: Being a parent of a child with type 1 diabetes involves a major life adjustment, which can contribute to stress, anxiety, and strain on relationships. Parents carry a significant responsibility for the child’s self-care. The nurse should provide empathy, clear information, and continuous support. Reducing parental burden and strengthening their well-being can help them support their child in the best possible way
Att utveckla och begreppsvalidera ett mätverktyg för skattning av samverkan
No full textBakgrund: Genom interorganisatorisk samverkan skapas förutsättningar för långtidsarbetslösa att bli hjälpt av flera aktörer och flera insatser samtidigt. I förlängningen kan den samverkan leda till anställning. Tillika har de svenska regeringarna under de senaste årtionden betonat vikten av samverkan mellan Arbetsförmedlingen och kommunala arbetsmarknadsenheter för att minska andelen långtidsarbetslösa. Samtidigt saknades enkäter för att skatta samverkan mellan de två organisationerna. Därför fanns behovet att en ny enkät utvecklades och säkerställdes att den teoretiska förståelsen av fenomenet överensstämde med verkligheten (begreppsvaliditet). Syfte: Syftet med denna studie var att utveckla och begreppsvalidera ett mätinstrument för skattning av samverkan mellan kommunala arbetsmarknadsenheter och Arbetsförmedlingen.Metod: En enkät bestående av 23 frågor utvecklades i fyra steg. Inledningsvis kartlades interorganisatorisk samverkan teoretiskt. Därefter sammanställdes enkätfrågor förankrade i kartläggningen och följande gavs återkoppling av forskare inom samverkansforskning. Avslutningsvis skedde ett urval av enkätfrågor av samverkansexperter för att subjektivt kunna fastställa att interorganisatorisk samverkan mäts. Därefter begreppsvaliderades enkäten genom kognitiva intervjuer. Målet var att identifiera problem i mätverktyget som innebar att den teoretiska förståelsen av interorganisatoriska samverkan inte överensstämde med hur det sker i praktiken. Conrad & Blairs kodningstabell brukades i dataanalysen.Resultat: I enkäten identifierades 10 problem, vilket berörde 8 frågor och visade på brister i dess begreppsvaliditet. Slutsats: I denna studie har en enkät för att skatta samverkan mellan Arbetsförmedlingen och kommunala arbetsmarknadsenheter utvecklats. Efter justeringar, baserat på identifierade problem i enkäten, säkerställdes dess begreppsvaliditet. Samtidigt, på grund av studiens avgränsningar rekommenderas fortsatta studier av dess validitet
Screening and surveillance practices for Multiple Endocrine Neoplasia type 1-related Neuroendocrine Tumours in European Neuroendocrine Tumor Society Centers of Excellence (ENETS CoE) : An ENETS MEN1 task force questionnaire study
No full textMultiple Endocrine Neoplasia type 1 (MEN1) Clinical Practice Guidelines (2012) are predominantly based on expert opinion due to limited available evidence at the time, leaving room for interpretation and variation in practices. Evidence on the natural course of MEN1-related neuroendocrine tumours (NET) and the value of screening programs has increased and new imaging techniques have emerged. The aim of this study is to provide insight in the current practices of screening and surveillance for MEN1-related NETs in ENETS Centers of Excellence (CoEs). A clinical practice questionnaire was distributed among all 65 ENETS CoEs. Response rate was 91% (59/65). In 14% of CoEs <10 patients, in 50% 10-49, in 31% 50-100 and in 3 centres (5%) >100 patients with MEN1 are seen. Practices with regard to screening and surveillance of NETs were markedly heterogeneous. Differences between countries were noted in the use of gut hormones for biochemical screening and the choice for imaging modality for screening/surveillance of pancreatic NETs (PanNETs). Magnetic resonance imaging (MRI) is the preferred modality for screening and surveillance of PanNETs, whereas this is computed tomography (CT) for thoracic NETs. Practices regarding screening for thoracic NETs were more homogeneous among larger volume CoEs, with longer screening intervals. The majority of CoEs tailored the surveillance of small pancreatic and lung NETs to observed growth rate. 68% of CoEs advise patients with clinical MEN1 with negative genetic testing to undergo periodic screening like mutation-positive patients. In conclusion, there is still marked heterogeneity in practice, although there are also common trends. Differences were sometimes associated with volume or country, but often no association was found. This underscores the need for clear and evidence-based practice recommendations
Revealing Deepfakes : A Netnographic Study of Users' Approaches in Online Communities
No full textAs AI-generated content becomes increasingly realistic and accessible, the need to understand how people detect manipulated media such as deepfakes is growing. This study explores the strategies used within online communities to identify image- and video-based deepfakes. Employing a netnographic approach, empirical data was collected from discussions on Reddit and analyzed using thematic analysis as outlined by Braun and Clarke (2006). The findings resulted in five overarching themes: Intuition, Image Quality, Contextual Improbability, Own Expertise, and Visual Anomalies. These themes illustrate that users do not rely solely on one approach but often shift between them or use them in combination. This suggests that the strategies are not mutually exclusive but rather flexibly employed in users’ attempts to assess the credibility of content. The study further connects these strategies to cognitive heuristics such as expectancy violation, self-confirmation and consistency. The results contribute to a deeper understanding of information evaluation strategies in everyday scenarios and shed light on how heuristics function as mental shortcuts in the evaluating of digital media
Nurses' experiences of preconditions for the care of patients with palliative care needs in inpatient care : A literature review
No full textBakgrund: Palliativ vård syftar till att lindra lidande och öka livskvalitet. Behovet av palliativ vård är stort och förväntas öka. Den palliativa vården förekommer i flera olika kontexter där slutenvården är den vanligaste platsen för dödsfall. Sjukhusvården bör aktivt kunna ge god palliativ vård på en allmän nivå, även i livets slutskede. Internationellt har sjuksköterskor en betydande roll i att ta hand om personer med dessa behov. Tillgång till palliativ vård ska ges på lika villkor och vara tillgänglig för alla. Det är därför av vikt att det finns förutsättningar för sjuksköterskor att kunna tillhandahålla denna vård av god kvalitet i all typ vård. Syfte: Att beskriva sjuksköterskors upplevelser av förutsättningar för att vårda patienter med palliativa vårdbehov i slutenvården. Metod: En litteraturstudie med induktiv ansats. Litteratursökningar har genomförts i databaserna PubMed och CINAHL. Totalt 15 kvalitativa artiklar analyserades och syntetiserades till teman. Resultat: I litteraturstudiens resultat framkom flera viktiga upplevelser av förutsättningar för att kunna vårda patienter med palliativa vårdbehov i slutenvården. Detta beskrevs genom tre framkomna huvudteman Samarbete, Organisatoriska aspekter och Stödjande tillgångar. I resultatet ingick aspekter av förutsättningar utifrån teamarbete, kommunikation med patienter och närstående, tydligt beslutsfattande, riktlinjer, resurser, grundkunskaper och känslomässigt stöd. Slutsats: Sjuksköterskor upplever förutsättningar som teamarbete, kommunikation med patienter och närstående, tydligt beslutsfattande, riktlinjer, resurser, grundkunskaper och känslomässigt stöd för att det ska vara möjligt att tillgodose palliativ vård i slutenvården. Dessa förutsättningar finns dock inte alltid tillgängliga. Slutsatsen är att flera aspekter behöver utvecklas för att sjuksköterskor ska ha förutsättningar för att kunna ge god palliativ vård till patienter som vårdas inom slutenvården. Background: Palliative care aims to relieve suffering and improve quality of life. The need for palliative care is significant and expected to increase. Palliative care is provided in various contexts, with inpatient care being the most common setting for death. Hospital care should actively provide high-quality general palliative care, even at the end of life. Internationally, nurses play a crucial role in caring for individuals with these needs. Access to palliative care should be provided on equal terms and be available to everyone. Therefore, it is essential to ensure that nurses have the necessary preconditions to provide high-quality palliative care in all types of healthcare settings. Aim: To describe nurses' experiences of the preconditions for the care of patients with palliative care needs in inpatient care. Method: A literature study with an inductive approach. Literature searches were conducted in the databases PubMed and CINAHL. A total of 15 qualitative articles were analyzed and synthesized into themes. Results: The results of the literature study suggested that there are experiences of several important preconditions for providing care to patients with palliative care needs in inpatient care. This was described through three main themes that emerged: Collaboration, Organizational aspects, and Supportive assets. The results included aspects of preconditions based on teamwork, communication with patients and relatives, clear decision-making, guidelines, resources, fundamental knowledge and emotional support. Conclusion: Nurses experience preconditions such as teamwork, communication with patients and relatives, clear decision-making, guidelines, resources, fundamental knowledge, and emotional support as necessary to provide palliative care in inpatient care. However, these conditions are not always available. The conclusion is that several aspects need to be developed to ensure that nurses have the necessary preconditions to provide quality palliative care to patients in inpatient care.
Addressing grand ecological challenges in aquatic ecosystems : how can mesocosms be used to advance solutions?
No full textRapid and drastic anthropogenic impacts are affecting global biogeochemical processes and driving biodiversity loss across Earth's ecosystems. In aquatic ecosystems, species distributions are shifting, abundances of many species have declined dramatically, and many are threatened with extinction. In addition to loss of diversity, the ecosystem functions, processes and services on which humans depend are also being heavily impacted. Addressing these challenges not only requires direct action to mitigate environmental impacts but also innovative approaches to identify, quantify and treat their effects in the environment. Mesocosms are valuable tools for achieving these goals as they provide controlled environments for evaluating effects of stressors and testing novel mitigation measures at multiple levels of biological organisation. Here, we summarise discussions from a survey of marine and freshwater researchers who use mesocosm systems to synthesise their opportunities and limitations for advancing solutions to grand ecological challenges in aquatic ecosystems. While most research utilising mesocosm systems in aquatic ecology has focused on quantifying the effects of environmental threats, there is a largely unexplored potential for using them to test solutions. To overcome spatio-temporal constraints, there are opportunities to scale up the size and time-scales of mesocosm studies, or alternatively, test the outcomes of habitat-scale restoration at a smaller scale. Enhancing connectivity in future studies can help to overcome the limitation of isolation and test an important aspect of ecological recovery. Conducting 'metacosm' studies: coordinated, distributed mesocosm experiments spanning wide climatic and environmental gradients and utilising more regression-based experimental designs can help to tackle the challenge of context dependent results. Finally, collaboration of theoretical, experimental and applied ecologists and biogeochemists with environmental engineers and technological developers will be necessary to develop and test the tools required to advance solutions to the impacts of human activities on Earth's vulnerable aquatic ecosystems
Spacecraft discharge time constants determined from electron-flux suppression during sounding-radar operation at Mars
No full textSpacecraft discharge time constants are calculated from measurements of electron differential flux before and during operation of an ionospheric sounding radar. Determining these time constants provides insight into how the operation of a sounding radar affects the surrounding plasma's interaction with the spacecraft. The analysis is enabled by the fixed-frequency operation mode of a sounding radar which enhances resonant interaction with the ambient plasma. This mode's effect on measured energy spectra of ion and electron fluxes is described. Measurements of electron fluxes disturbed by radar operation serve as input to a model of spacecraft discharge for calculating capacitive discharge time constants. A case study using electron fluxes measured at Mars yields discharge time constants in the range 0.6–0.8 ms and reveals that a residual potential around (Formula presented.) V remains on the spacecraft long after radar operation ceases. The minimum spacecraft potential cannot be determined with these data and model due to the narrow energy range of electrons in the ambient plasma
Numerical Study of Fluid Flow, Heat Transfer and Parameter Coupling in a Spider Web Microchannel Heat Sink
No full textThe microchannel heat sink is a commonly used structure in mechanical cooling systems for microelectronics. Based on bionics, a simplified heat sink with a spider-web design is proposed in this paper. Under the condition of bottom heat flux q = 100 W/cm2 and Reynolds number (Re) = 442-884, the influence of three parameters (main channel width, branch width and rib width) on the performance of a spider web microchannel heat sink (SW-MCHS) under different Re conditions was numerically analyzed by computational fluid dynamics. The results showed that the main channel had the greatest influence on the Nusselt number (Nu) and the Euler number (Eu); With the increase of main channel width, Nu increased by 46.97%, and Eu decreased by 31.74%. Rib width had the smallest influence on Nu and Eu; AWith the increase of rib width, Nu decreased by 7.18%, and Eu decreased by 12.00%. Based on the research results, the correlations for predicting Nu and Eu of the SW-MCHS were fitted; the Radj2 values for the two correlations were 0.9523 and 0.9246, respectively. These fitting correlations could be used to predict Nu and Eu for the SW-MCHS. The present study has contributed to advancing the applications of microchannel heat sinks and enhancing the cooling efficiency of mechanical microelectronics cooling systems