| 1. |
- Abdo, A. A., et al.
(författare)
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Multi-wavelength observations of the flaring gamma-ray blazar 3C 66A in 2008 October
- 2011
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Ingår i: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 726:1, s. 43-
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Tidskriftsartikel (refereegranskat)abstract
- The BL Lacertae object 3C 66A was detected in a flaring state by the Fermi Large Area Telescope (LAT) and VERITAS in 2008 October. In addition to these gamma-ray observations, F-GAMMA, GASP-WEBT, PAIRITEL, MDM, ATOM, Swift, and Chandra provided radio to X-ray coverage. The available light curves show variability and, in particular, correlated flares are observed in the optical and Fermi-LAT gamma-ray band. The resulting spectral energy distribution can be well fitted using standard leptonic models with and without an external radiation field for inverse Compton scattering. It is found, however, that only the model with an external radiation field can accommodate the intra-night variability observed at optical wavelengths.
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| 2. |
- Acciari, V. A., et al.
(författare)
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Discovery of very high energy gamma rays from PKS 1424+240 and multiwavelength constraints on ITS redshift
- 2010
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Ingår i: ASTROPHYSICAL JOURNAL LETTERS. - 2041-8205. ; 708:2, s. L100-L106
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Tidskriftsartikel (refereegranskat)abstract
- We report the first detection of very high energy(83) (VHE) gamma-ray emission above 140 GeV from PKS 1424+240, a BL Lac object with an unknown redshift. The photon spectrum above 140 GeV measured by VERITAS is well described by a power law with a photon index of 3.8 +/- 0.5(stat) +/- 0.3(syst) and a flux normalization at 200 GeV of (5.1 +/- 0.9(stat) +/- 0.5(syst)) x 10(-11) TeV-1 cm(-2) s(-1), where stat and syst denote the statistical and systematical uncertainties, respectively. The VHE flux is steady over the observation period between MJD 54881 and 55003 (from 2009 February 19 to June 21). Flux variability is also not observed in contemporaneous high-energy observations with the Fermi Large Area Telescope. Contemporaneous X-ray and optical data were also obtained from the Swift XRT and MDM observatory, respectively. The broadband spectral energy distribution is well described by a one-zone synchrotron self-Compton model favoring a redshift of less than 0.1. Using the photon index measured with Fermi in combination with recent extragalactic background light absorption models it can be concluded from the VERITAS data that the redshift of PKS 1424+240 is less than 0.66.
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| 3. |
- Acciari, V. A., et al.
(författare)
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Radio Imaging of the Very-High-Energy gamma-Ray Emission Region in the Central Engine of a Radio Galaxy
- 2009
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 325:5939, s. 444-448
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Tidskriftsartikel (refereegranskat)abstract
- The accretion of matter onto a massive black hole is believed to feed the relativistic plasma jets found in many active galactic nuclei (AGN). Although some AGN accelerate particles to energies exceeding 10(12) electron volts and are bright sources of very-high-energy (VHE) gamma-ray emission, it is not yet known where the VHE emission originates. Here we report on radio and VHE observations of the radio galaxy Messier 87, revealing a period of extremely strong VHE gamma-ray flares accompanied by a strong increase of the radio flux from its nucleus. These results imply that charged particles are accelerated to very high energies in the immediate vicinity of the black hole.
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| 4. |
- Acciari, V. A., et al.
(författare)
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THE DISCOVERY OF gamma-RAY EMISSION FROM THE BLAZAR RGB J0710+591
- 2010
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Ingår i: ASTROPHYSICAL JOURNAL LETTERS. - 2041-8205. ; 715:1, s. L49-L55
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Tidskriftsartikel (refereegranskat)abstract
- The high-frequency-peaked BL Lacertae object RGB J0710+591 was observed in the very high-energy (VHE; E > 100 GeV) wave band by the VERITAS array of atmospheric Cherenkov telescopes. The observations, taken between 2008 December and 2009 March and totaling 22.1 hr, yield the discovery of VHE gamma rays from the source. RGB J0710+591 is detected at a statistical significance of 5.5 standard deviations (5.5 sigma) above the background, corresponding to an integral flux of (3.9 +/- 0.8) x 10(-12) cm(-2) s(-1) (3% of the Crab Nebula's flux) above 300 GeV. The observed spectrum can be fit by a power law from 0.31 to 4.6 TeV with a photon spectral index of 2.69 +/- 0.26(stat) +/- 0.20(sys). These data are complemented by contemporaneous multiwavelength data from the Fermi Large Area Telescope, the Swift X-ray Telescope, the Swift Ultra-Violet and Optical Telescope, and the Michigan-Dartmouth-MIT observatory. Modeling the broadband spectral energy distribution (SED) with an equilibrium synchrotron self-Compton model yields a good statistical fit to the data. The addition of an external-Compton component to the model does not improve the fit nor brings the system closer to equipartition. The combined Fermi and VERITAS data constrain the properties of the high-energy emission component of the source over 4 orders of magnitude and give measurements of the rising and falling sections of the SED.
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| 5. |
- Ademuyiwa, Adesoji O., et al.
(författare)
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Determinants of morbidity and mortality following emergency abdominal surgery in children in low-income and middle-income countries
- 2016
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Ingår i: BMJ Global Health. - : BMJ Publishing Group Ltd. - 2059-7908. ; 1:4
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Tidskriftsartikel (refereegranskat)abstract
- Background: Child health is a key priority on the global health agenda, yet the provision of essential and emergency surgery in children is patchy in resource-poor regions. This study was aimed to determine the mortality risk for emergency abdominal paediatric surgery in low-income countries globally.Methods: Multicentre, international, prospective, cohort study. Self-selected surgical units performing emergency abdominal surgery submitted prespecified data for consecutive children aged <16 years during a 2-week period between July and December 2014. The United Nation's Human Development Index (HDI) was used to stratify countries. The main outcome measure was 30-day postoperative mortality, analysed by multilevel logistic regression.Results: This study included 1409 patients from 253 centres in 43 countries; 282 children were under 2 years of age. Among them, 265 (18.8%) were from low-HDI, 450 (31.9%) from middle-HDI and 694 (49.3%) from high-HDI countries. The most common operations performed were appendectomy, small bowel resection, pyloromyotomy and correction of intussusception. After adjustment for patient and hospital risk factors, child mortality at 30 days was significantly higher in low-HDI (adjusted OR 7.14 (95% CI 2.52 to 20.23), p<0.001) and middle-HDI (4.42 (1.44 to 13.56), p=0.009) countries compared with high-HDI countries, translating to 40 excess deaths per 1000 procedures performed.Conclusions: Adjusted mortality in children following emergency abdominal surgery may be as high as 7 times greater in low-HDI and middle-HDI countries compared with high-HDI countries. Effective provision of emergency essential surgery should be a key priority for global child health agendas.
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| 6. |
- Dubois, Hanna
(författare)
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Level with me! Exploring patient participation in short-term clinical encounters in team-based settings
- 2022
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Patient participation has been described as patients’ opportunities for involvement in different parts of their care. Benefits, including improved patient safety, health outcomes and patient satisfaction have been associated with patient participation. However, although patient participation is promoted in legislation and by international organisations, there are signs of deficits in different healthcare settings. It also appears that patient participation is context dependent and defined differently across contexts. Some healthcare settings, for example, short-term care relationships in team-based contexts, have been less explored. As it appears that greater patient participation is needed in the healthcare system, understanding what it actually means in different contexts is essential to identifying strategies to improve patient participation. Aims: The overall aims of this thesis were, first, to contribute to knowledge and understanding about patient participation in short-term clinical encounters in team-based settings, and second, to provide and evaluate strategies to enable patient participation for such settings. Methods: In this thesis, two different Swedish clinical settings characterised by short-term care encounters were explored: gastrointestinal (GI) endoscopy in a university hospital and rural emergency care in which telemedicine is used to connect a physician to the rest of the team (i.e. ‘tele-emergency’). Qualitative methods were used to explore patients’ (Study II) and healthcare professionals’ (HCP’s) (Study III) attitudes, experiences and perceptions of patient participation in the respective settings. Semi-structured interviews were performed individually or in groups. Interview transcripts were analysed using qualitative content analysis. For the GI endoscopy setting, a safety checklist with a person-centered approach was developed and introduced (Study I). A cross-sectional design was used to evaluate the checklist intervention (before-after). Data collection included questionnaires and structured observations. In study IV, an observational tool was developed and tested to assess and provide feedback to emergency teams regarding patient involvement and collaboration behaviour. The development of the tool was based on published literature, interview transcripts and videorecordings from simulated emergency scenarios. An international expert panel reviewed the tool’s content for validity. The feasibility and inter-rater reliability of the tool were also assessed. Results: In GI endoscopy (Study II), the patients described their level of participation as active or passive and reported whether they were included or excluded by the HCPs. Factors influencing patient participation in GI endoscopy were identified, including the perceptions of the HCPs, personal characteristics or circumstances, and organisational aspects. Opportunities for increased patient participation during the endoscopy pathway were identified. In Study III, patient participation in tele-emergencies was described by HCPs. Building a trusting relationship was essential for patient participation in emergencies. The video setup frequently became a ‘barrier’ between the HCPs and the patients, and the team’s communication over the video-conference system endangered the already weak position of the patient. The familiarity in the patient-HCP relationship, which is often typical of rural healthcare, was negatively affected when a physician unknown to the patient appeared on the screen. HCPs also described a need for a ‘private room’, without the patient, to discuss sensitive topics. Two strategies to enhance patient participation were successfully developed and evaluated, one for GI endoscopy and one for emergency care. In Study I, the most notable result was that physicians started participating in patient identity checks (from 0% to 87%) 10 months after the checklist intervention (p < 0.001). Nurses participated in the identity checks to a high degree both before and after the intervention. Structured observations showed that the checklist was used frequently, but adherence was suboptimal. The staff questionnaires showed a tendency towards increased awareness of patient participation and improvements in the teamwork climate. Patients reported overall high satisfaction before the intervention, which remained unchanged. In Study IV, the PIC-ET (Patient Involvement and Collaboration in Emergency Teams) tool was developed, a 22-item observational instrument for team assessment in emergency care. Using this tool, a team’s patient involvement and collaboration (PIC) behaviour can be rated from ‘no PIC’ to ‘High PIC’. The PIC-ET tool was found to be feasible, and the content validity was good. The tool was viewed as useful for clinical assessments, research and education. Inter-rater reliability was ‘fair’. Conclusions: This thesis contributes knowledge on patient participation in short-term clinical encounters in team-based settings by providing descriptions of what participation means to patients and HCPs within two different settings: GI endoscopy and rural emergency care. The results suggest that context influences how patient participation is interpreted, but also that it is highly dependent on the personal characteristics of the patients and HCPs, their expectations and previous experiences. In both settings, patient participation was described as possible and desirable. However, the patient often seems to have an inferior position. For increased patient participation, mutual trust, open dialogue, and sharing of knowledge and power are important. Two strategies for enhancing patient participation were developed and tested. Both methods show promising features, and future research should be conducted to generate more robust evidence.
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| 7. |
- Dubois, Hanna, et al.
(författare)
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Patient participation in gastrointestinal endoscopy : From patients' perspectives
- 2020
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Ingår i: Health Expectations. - : Wiley. - 1369-6513 .- 1369-7625. ; 23:4, s. 893-903
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Patient participation is associated with satisfaction and improved health-related outcomes. In gastrointestinal endoscopy, patient participation is an underexplored area.OBJECTIVE: To gain understanding on patients' experiences, attitudes and preferences concerning patient participation in the endoscopy pathway.METHODS: Semi-structured interviews with endoscopy patients (n = 17, female n = 8, male n = 9, ages 19-80 years) were performed. Interview transcripts were analysed using qualitative content analysis. Participants were recruited by purposive sampling from an endoscopy unit in a Swedish university hospital. Inclusion:≥ 18 years, fluency in Swedish and recent experience of endoscopy at the unit.RESULTS: Five generic categories emerged, two within the area of the patient's role, which was described as active or passive/included or excluded. Another three generic categories related to factors, critical to active participation, including organizational aspects, impressions of staff and individual circumstances were identified. In this context, patient participation described in the interviews was on a low to basic level, although sometimes reaching a higher level when staff 'invited' patients in decision making.DISCUSSION: This study contributes to the understanding of patient participation in endoscopy. Patients are in an inferior position and need support from the staff for an active role in their care. Although there were variations on the perceived importance of different factors, a heavy responsibility lies on the endoscopy staff to acknowledge the patients' individual needs and to facilitate patient participation.CONCLUSIONS: Endoscopy staff has a key role in supporting patient participation. In endoscopy settings, patient participation is vulnerable to multiple factors.
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| 8. |
- Dubois, Hanna, et al.
(författare)
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Patient participation in tele-emergencies : experiences from healthcare professionals in northern rural Sweden
- 2022
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Ingår i: Rural and remote health. - 1445-6354. ; 22:4
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Telemedicine provides opportunities for access to health care in remote and underserved areas. In parts of northern rural Sweden telemedicine is used to connect a remote physician by a video-conference system to an emergency room, staffed by nurses during on-call hours. This can be called 'tele-emergency'. Patient participation, often described as mutual information exchange, a trustful relationship and involvement in decision-making, is challenged in emergency care by short encounters, deteriorating patients and a stressful work situation. Nevertheless, patient participation may be important for the patients' experience. Healthcare professionals (HCPs) have been identified as 'gatekeepers' for patient participation, therefore putting their perspective in focus is important. As emergency care in rural areas is increasingly turning toward telemedicine, patient participation in tele-emergencies needs to be better understood. The aim of this study was to explore and characterise HCPs' perspectives of patient participation in tele-emergencies in northern rural Sweden.METHODS: A qualitative design based on interviews was used. HCPs working in cottage hospitals in northern rural Sweden were included. Semi-structured interviews were performed, first, in multidisciplinary groups of three informants. Later, because of limited experience of tele-emergencies in the groups, individual interviews with HCPs with substantial experience were added. A qualitative content analysis of the interview transcripts was conducted.RESULTS: A total of 44 HCPs from northern inland Sweden participated in the interviews. The content analysis resulted in two themes, six categories and 19 subcategories. Theme 1, 'To see, understand, and to build trust through the digital barrier', contains descriptions of the interpersonal relationship between the patient and the HCPs, and the challenges when interacting with the patient during a tele-emergency. The informants also described a need for boundaries between the professional team and the patient. The categories in theme 1 are 'understanding the patient's point of view', 'building a trustful relationship', and 'needing a private space without the patient'. Theme 2, 'The (im)balance of power - tele-emergency reinforces the positions', mirrors the power asymmetry in the patient-professional relationship, and the potential impact of the tele-emergency on the different roles. Tele-emergencies were described as a risk that potentially could weaken the patient's position, but also as providing an opportunity to share power. Categories in theme 2 are 'medical conditions limit patient participation', 'patient involvement in decision-making requires understanding' and 'the inferior patient and the superior professionals'.CONCLUSION: This study sheds light on patient participation in tele-emergencies in a remote rural setting from the HCP's perspective. The tele-emergency set-up affected patient participation by interfering with familiar patient-HCP relationships and changing group dynamics in interactions with the patient. Due to the extensive changes of the conditions for patient participation imposed in tele-emergencies, suggestions for actions improving patient participation are made.
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| 9. |
- Dubois, Louise, et al.
(författare)
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Evaluating real-time immunohistochemistry on multiple tissue samples, multiple targets and multiple antibody labeling methods
- 2013
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Ingår i: BMC Research Notes. - : Springer Science and Business Media LLC. - 1756-0500. ; 6, s. 542-
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundImmunohistochemistry (IHC) is a well-established method for the analysis of protein expression in tissue specimens and constitutes one of the most common methods performed in pathology laboratories worldwide. However, IHC is a multi-layered method based on subjective estimations and differences in staining and interpretation has been observed between facilities, suggesting that the analysis of proteins on tissue would benefit from protocol optimization and standardization. Here we describe how the emerging and operator independent tool of real-time immunohistochemistry (RT-IHC) reveals a time resolved description of antibody interacting with target protein in formalin fixed paraffin embedded tissue. The aim was to understand the technical aspects of RT-IHC, regarding generalization of the concept and to what extent it can be considered a quantitative method.ResultsThree different antibodies labeled with fluorescent or radioactive labels were applied on nine different tissue samples from either human or mouse, and the results for all RT-IHC analyses distinctly show that the method is generally applicable. The collected binding curves showed that the majority of the antibody-antigen interactions did not reach equilibrium within 3 hours, suggesting that standardized protocols for immunohistochemistry are sometimes inadequately optimized. The impact of tissue size and thickness as well as the position of the section on the glass petri dish was assessed in order for practical details to be further elucidated for this emerging technique. Size and location was found to affect signal magnitude to a larger extent than thickness, but the signal from all measurements were still sufficient to trace the curvature. The curvature, representing the kinetics of the interaction, was independent of thickness, size and position and may be a promising parameter for the evaluation of e.g. biopsy sections of different sizes.ConclusionsIt was found that RT-IHC can be used for the evaluation of a number of different antibodies and tissue types, rendering it a general method. We believe that by following interactions over time during the development of conventional IHC assays, it becomes possible to better understand the different processes applied in conventional IHC, leading to optimized assay protocols with improved sensitivity.
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| 10. |
- Gedda, Lars, et al.
(författare)
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Evaluation of Real-Time Immunohistochemistry and Interaction Map as an Alternative Objective Assessment of HER2 Expression in Human Breast Cancer Tissue
- 2013
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Ingår i: Applied immunohistochemistry & molecular morphology (Print). - 1541-2016 .- 1533-4058. ; 21:6, s. 497-505
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Tidskriftsartikel (refereegranskat)abstract
- Immunohistochemical study (IHC) is a critical tool in the clinical diagnosis of breast cancer. One common assessment is the expression level of the HER2 receptor in breast cancer tissue samples with the aim of stratifying patients for applicability of the therapeutic antibody Herceptin. In this study, we aimed to investigate whether a novel assay, real-time IHC combined with Interaction Map analysis, offers the possibility of objective assessment of HER2 expression. Interaction Map presents real-time interaction data as a collection of peaks on a surface, and it was performed on 20 patient tissue samples previously scored for HER2 expression. The result shows that the relative weight of the peaks in the maps contains novel information that could discriminate between high and low HER2 expression in an operator-independent manner (P<0.001). We conclude that the real-time IHC assay has a promising potential to complement conventional IHC and may improve the precision in the future clinical diagnostics of breast cancer.
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