Imaging x-ray spectrometer at the high energy density instrument of the European x-ray free electron laser

A multipurpose imaging x-ray crystal spectrometer is developed for the high energy density instrument of the European X-ray Free Electron Laser. The spectrometer is designed to measure x rays in the energy range of 4-10 keV, providing high-resolution, spatially resolved spectral measurements. A toroidally bent germanium (Ge) crystal is used, allowing x-ray diffraction from the crystal to image along a one-dimensional spatial profile while spectrally resolving along the other. A detailed geometrical analysis is performed to determine the curvature of the crystal. The theoretical performance of the spectrometer in various configurations is calculated by ray-tracing simulations. The key properties of the spectrometer, including the spectral and spatial resolution, are demonstrated experimentally on different platforms. Experimental results prove that this Ge spectrometer is a powerful tool for spatially resolved measurements of x-ray emission, scattering, or absorption spectra in high energy density physics.

Microstructured layered targets for improved laser-induced x-ray backlighters

We present the usage of two-layer targets with laser-illuminated front-side microstructures for x-ray backlighter applications. The targets consisted of a silicon front layer and copper back side layer. The structured layer was irradiated by the 500-fs PHELIX laser with an intensity above 10^{20}Wcm^{-2}. The total emission and one-dimensional extent of the copper Kα x-ray emission as well as a wide spectral range between 7.9 and 9.0 keV were recorded with an array of crystal spectrometers. The measurements show that the front-side modifications of the silicon in the form of conical microstructures maintain the same peak brightness of the Kα emission as flat copper foils while suppressing the thermal emission background significantly. The observed Kα source sizes can be influenced by tilting the conical microstructures with respect to the laser axis. Overall, the recorded copper Kα photon yields were in the range of 10^{11}sr^{-1}, demonstrating the suitability of these targets for probing applications without subjecting the probed material to additional heating from thermal line emission.

Erratum: Measurement of Preheat Due to Nonlocal Electron Transport in Warm Dense Matter [Phys. Rev. Lett. 120, 025002 (2018)]

This corrects the article DOI: 10.1103/PhysRevLett.120.025002.

Single-Shot Multi-keV X-Ray Absorption Spectroscopy Using an Ultrashort Laser-Wakefield Accelerator Source

Single-shot absorption measurements have been performed using the multi-keV x rays generated by a laser-wakefield accelerator. A 200 TW laser was used to drive a laser-wakefield accelerator in a mode which produced broadband electron beams with a maximum energy above 1 GeV and a broad divergence of ≈15  mrad FWHM. Betatron oscillations of these electrons generated 1.2±0.2×10^{6}  photons/eV in the 5 keV region, with a signal-to-noise ratio of approximately 300∶1. This was sufficient to allow high-resolution x-ray absorption near-edge structure measurements at the K edge of a titanium sample in a single shot. We demonstrate that this source is capable of single-shot, simultaneous measurements of both the electron and ion distributions in matter heated to eV temperatures by comparison with density functional theory simulations. The unique combination of a high-flux, large bandwidth, few femtosecond duration x-ray pulse synchronized to a high-power laser will enable key advances in the study of ultrafast energetic processes such as electron-ion equilibration.

Laser-wakefield accelerators for high-resolution X-ray imaging of complex microstructures

Laser-wakefield accelerators (LWFAs) are high acceleration-gradient plasma-based particle accelerators capable of producing ultra-relativistic electron beams. Within the strong focusing fields of the wakefield, accelerated electrons undergo betatron oscillations, emitting a bright pulse of X-rays with a micrometer-scale source size that may be used for imaging applications. Non-destructive X-ray phase contrast imaging and tomography of heterogeneous materials can provide insight into their processing, structure, and performance. To demonstrate the imaging capability of X-rays from an LWFA we have examined an irregular eutectic in the aluminum-silicon (Al-Si) system. The lamellar spacing of the Al-Si eutectic microstructure is on the order of a few micrometers, thus requiring high spatial resolution. We present comparisons between the sharpness and spatial resolution in phase contrast images of this eutectic alloy obtained via X-ray phase contrast imaging at the Swiss Light Source (SLS) synchrotron and X-ray projection microscopy via an LWFA source. An upper bound on the resolving power of 2.7 ± 0.3 μm of the LWFA source in this experiment was measured. These results indicate that betatron X-rays from laser wakefield acceleration can provide an alternative to conventional synchrotron sources for high resolution imaging of eutectics and, more broadly, complex microstructures.

Seroepidemiological Studies of Arboviruses in Africa

The literature on sero-epidemiological studies of flaviviral infections in the African continent is quite scarce. Much of the viral epidemiology studies have been focussing on diseases such as HIV/AIDS because of their sheer magnitude and impact on the lives of people in the various affected countries. Increasingly disease outbreaks caused by arboviruses such as the recent cases of chikungunya virus, dengue virus and yellow fever virus have prompted renewed interest in studying these viruses. International agencies from the US, several EU nations and China are starting to build collaborations to build capacity in many African countries together with established institutions to conduct these studies. The Tofo Advanced Study Week (TASW) was established to bring the best scientists from the world to the tiny seaside town of Praia do Tofo to rub shoulders with African virologists and discuss cutting-edge science and listen to the work of researchers in the field. In 2015 the 1st TASW focussed on Ebola virus. The collections of abstracts from participants at the 2nd TASW which focused on Dengue and Zika virus as well as presentations on other arboviruses are collated in this chapter.

Measurement of Preheat Due to Nonlocal Electron Transport in Warm Dense Matter

This Letter presents a novel approach to study electron transport in warm dense matter. It also includes the first x-ray Thomson scattering (XRTS) measurement from low-density CH foams compressed by a strong laser-driven shock at the OMEGA laser facility. The XRTS measurement is combined with velocity interferometry (VISAR) and optical pyrometry (SOP) providing a robust measurement of thermodynamic conditions in the shock. Evidence of significant preheat contributing to elevated temperatures reaching 17.5-35 eV in shocked CH foam is measured by XRTS. These measurements are complemented by abnormally high shock velocities observed by VISAR and early emission seen by SOP. These results are compared to radiation hydrodynamics simulations that include first-principles treatment of nonlocal electron transport in warm dense matter with excellent agreement. Additional simulations confirm that the x-ray contribution to this preheat is negligible.

Effects of a mindfulness-based intervention on symptoms and signs in chronic heart failure: A feasibility study

Aims:

Despite treatment recommended by guidelines, many patients with chronic heart failure remain symptomatic. Evidence is accumulating that mindfulness-based interventions (MBIs) have beneficial psychological and physiological effects. The aim of this study was to explore the feasibility of MBI on symptoms and signs in patients with chronic heart failure in outpatient clinical settings.

Methods:

A prospective feasibility study. Fifty stable but symptomatic patients with chronic heart failure, despite optimized guideline-recommended treatment, were enrolled at baseline. In total, 40 participants (median age 76 years; New York Heart Association (NYHA) classification II−III) adhered to the study. Most patients (n=17) were randomized into MBI, a structured eight-week mindfulness-based educational and training programme, or controls with usual care (n=16). Primary outcome was self-reported fatigue on the Fatigue severity scale. Secondary outcomes were self-reported sleep quality, unsteadiness/dizziness, NYHA functional classification, walking distance in the six-minute walk test, and heart and respiratory rates. The Mann–Whitney U test was used to analyse median sum changes from baseline to follow-up (week 10±1).

Results:

Compared with usual care (zero change), MBI significantly reduced the self-reported impact of fatigue (effect size −8.0; p=0.0165), symptoms of unsteadiness/dizziness (p=0.0390) and breathlessness/tiredness related to physical functioning (NYHA class) (p=0.0087). No adverse effects were found.

Conclusions:

In stable but symptomatic outpatients with chronic heart failure, MBI alleviated self-reported symptoms in addition to conventional treatment. The sample size is small and further studies are needed, but findings support the role of MBI as a feasible complementary option, both clinically and as home-based treatment, which might contribute to reduction of the symptom burden in patients diagnosed with chronic heart failure.

Highly efficient angularly resolving x-ray spectrometer optimized for absorption measurements with collimated sources

Highly collimated betatron radiation from a laser wakefield accelerator is a promising tool for spectroscopic measurements. Therefore, there is a requirement to create spectrometers suited to the unique properties of such a source. We demonstrate a spectrometer which achieves an energy resolution of <5 eV at 9 keV (E∕ΔE>1800) and is angularly resolving the x-ray emission allowing the reference and spectrum to be recorded at the same time. The single photon analysis is used to significantly reduce the background noise. Theoretical performance of various configurations of the spectrometer is calculated by a ray-tracing algorithm. The properties and performance of the spectrometer including the angular and spectral resolution are demonstrated experimentally on absorption above the K-edge of a Cu foil backlit by a laser-produced betatron radiation x-ray beam.

Long-term secondary prevention of acute myocardial infarction (SEPAT) - guidelines adherence and outcome

Background

A number of registry studies have reported suboptimal adherence to guidelines for cardiovascular prevention during the first year after acute myocardial infarction (AMI). However, only a few studies have addressed long-term secondary prevention after AMI. This study evaluates prevention guideline adherence and outcome of guideline-directed secondary prevention in patients surviving 2 years after AMI.

Methods

Patients aged 18–85 years at the time of their index AMI were consecutively identified from hospital discharge records between July 2010 and December 2011 in Gothenburg, Sweden. All patients who agreed to participate in the study (16.2%) were invited for a structured interview, physical examinations and laboratory analysis 2 years after AMI. Guideline-directed secondary preventive goals were defined as optimally controlled blood pressure, serum cholesterol, glucose, regular physical activity, smoking cessation and pharmacological treatment.

Results

The mean age of the study cohort (n = 200) at the index AMI was 63.0 ± 9.7 years, 79% were men. Only 3.5% of the cohort achieved all six guideline-directed secondary preventive goals 2 years after infarction. LDL < 1.8 mmol/L was achieved in 18.5% of the cohort, regular exercise in 45.5% and systolic blood pressure <140 mmHg in 57.0%. Anti-platelet therapy was used by 97% of the patients, beta-blockers by 83.0%, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers by 76.5% and statins by 88.5%. During follow-up, non-fatal adverse cardiovascular events (cardiac hospitalization, recurrent acute coronary syndrome, angina pectoris, new percutaneous coronary intervention, new onset of atrial fibrillation, post-infarct heart failure, pacemaker implantation, stroke/transient ischemic attack (TIA), cardiac surgery and cardiac arrest) occurred in 47% of the cohort and readmission due to cardiac causes in 30%.

Conclusions

Our data showed the failure of secondary prevention in our daily clinical practice and high rate of non-fatal adverse cardiovascular events 2 years after AMI.

[GPs' Views on Barriers and Preconditions for Referring Elderly People with Depressive Disorder to Psychotherapy]

OBJECTIVE

Older people with depressive disorders access psychotherapy less frequently than younger ones. GPs play an important role in referring patients, particularly the elderly, to psychotherapeutic treatment. This paper presents the obstacles to and preconditions for referring older, depressed sick people to psychotherapy from the point of view of GPs.

METHODOLOGY

Doctors who are training GPs were given a questionnaire on the care of the elderly (60+) with depressive disorders. In 2 open questions, they were requested to state their views on obstacles to and preconditions for referring older, depressed diseased people to psychotherapeutic treatment.

RESULTS

Most statements related to obstacles perceived by patients followed by barriers on the part of the supply system. Especially obstructive attitudes and emotions, but also functional limitations on the part of patients were referred to as barriers. With regard to the supply system, structural aspects, such as lack of psychotherapy places, but also the actions of care providers and insufficient cooperation were listed. As preconditions, specific therapy for the elderly were mentioned CONCLUSIONS: Dealing with reservations about psychotherapy on the part of older people takes time, which usually is not reimbursed in general practice. Collaborations with psychotherapists are seen as an important precondition for referral. Especially for people with multiple illnesses, access is considered difficult.

Differences in Symptom Distress Based on Gender and Palliative Care Designation Among Hospitalized Patients

PURPOSE

To explore patient-reported symptom distress in relation to documentation of symptoms and palliative care designation in hospital inpatients.

DESIGN

This cross-sectional study analyzed data from 710 inpatients at two large hospitals in Sweden using the Edmonton Symptom Assessment Scale and the Memorial Symptom Assessment Scale. Chart reviews focused on nurses' and physicians' symptom documentation and palliative turning point.

METHODS

Descriptive statistics were calculated for all variables and provided summaries about the sample. Patients were grouped according to gender, age, palliative care designation, and symptom documentation. The t test and chi-square test were used to calculate whether symptom distress varied between groups. A two-way analysis of variance was conducted for multiple comparisons to explore the impact of gender and age on mean symptom distress.

FINDINGS

Females reported higher levels of symptom distress than did males related to pain, fatigue, and nausea. When comparing symptom distress between males and females with documentation pertaining to symptoms, there were significant differences implying that females had to report higher levels of symptom distress than males in order to have their symptoms documented.

CONCLUSIONS

Females need to report higher levels of symptom distress than do males for healthcare professionals to identify and document their symptoms. It can be hypothesized that females are not receiving the same attention and symptom alleviation as men. If so, this highlights a serious inequality in care that requires further exploration.

CLINICAL RELEVANCE

Considering that common reasons why people seek health care are troublesome symptoms of illness, and that the clinical and demographic characteristics of inpatients are changing towards more advanced ages with serious illnesses, inadequate symptom assessment and management are a serious threat to the care quality.

[GPs' Perceptions of Strengths and Shortcomings of the ICD-10 for Diagnosis of depression]

AIM

For the health care of people with depressive disorders, general practitioners are important contact persons. Some investigations have shown an under-diagnosis of these patients in GPs' surgeries. The significance of the ICD-10 for the diagnosis of depression is disputed. The BMBF-funded study "PSYTIA - Psychotherapy in old age" engages, among others, with the treatment of older people with depression in GPs' surgeries. This study presents the strengths and shortcomings of the ICD-10 for diagnosis of depression from the point of view of GPs.

METHODS

With the help of a questionnaire, 402 teaching GPs were asked how they diagnose and treat elderly people (60+) with depressive disorders in their practices. The response rate was 23.6%. 2 open-ended questions dealt with GPs' perceptions of strengths and shortcomings of ICD-10 for the diagnosis of depression. The responses were matched to inductively developed overarching categories.

RESULTS

About three-quarters of the respondents answered the 2 questions. While nearly one-fifth of the respondents did not state any opinion about the suitability of ICD-10 as a diagnostic instrument for depressive disorders, 41% of the respondents mentioned the shortcomings and one-third the strengths of ICD-10. Shortcomings and strengths relate primarily to the complexity of the instrument and its manageability in everyday practice.

CONCLUSIONS

The results show that application of ICD-10 in a GP's surgery depends on a holistic, hermeneutical approach to the case in family practice, a need for efficient practice management, and billing. These different perceptions explain the heterogeneous and ambivalent assessment of the suitability of ICD-10 for the diagnosis of depression.

Coronary changes in the Atlantic salmon Salmo salar L: characterization and impact of dietary fatty acid compositions

Consumption of fatty acids from fishes is widely regarded as beneficial for preventing cardiovascular disorders. Nevertheless, salmonids themselves are victims of vascular diseases. As the pathogenesis and nature of these changes are elusive, they are here addressed using novel morphological and transcriptional approaches. Coronary arteries of wild Atlantic salmon Salmo salar L., (n = 12) were investigated using histological and immunohistochemical techniques, and RT-qPCR was employed to investigate expression of stretch-induced genes. In an experimental trial, fish were fed diets with different fatty acids composition, and histological features of the coronary arteries (n = 36) were investigated. In addition, the heart fatty acid profile (n = 60) was analysed. There were no differences in morphological or immunological features between wild fish and groups of experimental fish. Arteriosclerotic lesions consisted of smooth muscle cells in dissimilar differential stages embedded in considerable amounts of extracellular matrix in a similar fashion to what is seen in early stages of human atherosclerosis. No fat accumulations were observed, and very few inflammatory cells were present. In affected arteries, there was an induction of stretch-related genes, pointing to a stress-related response. We suggest that salmon may have a natural resistance to developing atherosclerosis, which corresponds well with their high investment in lipid metabolism.

Atlantic salmon, Salmo salar L. are broadly susceptible to isolates representing the North American genogroups of infectious hematopoietic necrosis virus

Beginning in 1992, three epidemic waves of infectious hematopoietic necrosis, often with high mortality, occurred in farmed Atlantic salmon Salmo salar L. on the west coast of North America. We compared the virulence of eleven strains of infectious hematopoietic necrosis virus (IHNV), representing the U, M and L genogroups, in experimental challenges of juvenile Atlantic salmon in freshwater. All strains caused mortality and there was wide variation within genogroups: cumulative mortality for five U-group strains ranged from 20 to 100%, four M-group strains ranged 30-63% and two L-group strains varied from 41 to 81%. Thus, unlike Pacific salmonids, there was no apparent correlation of virulence in a particular host species with virus genogroup. The mortality patterns indicated two different phenotypes in terms of kinetics of disease progression and final per cent mortality, with nine strains having moderate virulence and two strains (from the U and L genogroups) having high virulence. These phenotypes were investigated by histopathology and immunohistochemistry to describe the variation in the course of IHNV disease in Atlantic salmon. The results from this study demonstrate that IHNV may become a major threat to farmed Atlantic salmon in other regions of the world where the virus has been, or may be, introduced.

Continuity means "preserving a consistent whole"--A grounded theory study

Living with a chronic disease like chronic heart failure (CHF) results in disruptions, losses, and setbacks in the participants’ daily lives that affect health and well-being. By using grounded theory method, we illuminate whether persons with CHF experience discontinuity in life and, if so, what helps them to preserve and strengthen continuity in their daily lives. Thirteen individual interviews and one group interview with five participants, aged 62 to 88 years, were carried out. Through data collection and data analysis, we constructed three concepts that make up a model illustrating the participants’ experiences in daily life in relation to corporeality, temporality, and identity: experiences of discontinuity, recapturing approaches, and reconciliation. The first concept, experiences of discontinuity, was constructed from the following categories: the alienated body, the disrupted time, and the threatened self. The second concept, recapturing approaches, consists of categories with continuity creative constructions: repossessing the body, maintaining a façade, seizing the day, restoring the balance of time, and preserving self. These actions are intended to overcome problems and master changes in order to maintain balance in daily life through constructions that recreate normality and predictability. The third concept, reconciliation, was constructed from three categories: feel normal, set to adjust, and be positioned. These categories describe how the participants minimize their experiences of discontinuity by recapturing approaches in order to reconcile with various changes and maintain continuity in daily life. Our findings provide a fresh perspective on continuity that may contribute to the development of significant interventions in continuity of care for persons with CHF. However, continuity requires that healthcare systems support each patient's ability to manage change, reorientation, and adjustment to the new situation in order to make it easier for the patient to create and continue living their daily lives as they desire.

Women's help-seeking behaviour during a first acute myocardial infarction

Studies indicate that the time from onset of symptoms to medical treatment has decreased in acute myocardial infarction (AMI). However, there are still variations indicating that women wait longer than men before making the decision to seek medical care. Multidimensional factors hindering and facilitating the decision have been identified in previous studies, though few have fully explored how social context affects women's expectations, interpretations and actions and so influences the decision-making process. The aim of this study was therefore to identify how women's experiences interacted and influenced the decision to seek medical care at their first AMI. Seventeen women, aged 38-75 years, were interviewed, at home or in the hospital, between June 2011 and May 2012. Grounded theory was used as a method, and data collection and analysis were carried out simultaneously. The results showed that before deciding to seek medical care, these women went through three defined but interrelated processes that together hindered their normal activities and made them act according to existential needs. The women's experiences of the progression of the disease, in terms of both symptoms and time, were very different, so they sought medical care at different times, sometimes life-threateningly late and sometimes before developing an AMI. Three mechanisms had to coincide if the women were to receive medical care. First, the women had to acknowledge their symptoms as something more than common bodily changes. Second, the healthcare system had to be accessible when the women made their decision to seek care. Third, the women must have come into contact with healthcare providers when the heart muscle had taken enough damage to measure.

Health Promotion Can Postpone Frailty: Results from the RCT Elderly Persons in the Risk Zone

OBJECTIVE

Very old persons (80+) are often described as "frail", implying that they are particularly vulnerable to adverse health outcomes. Elderly Persons in the Risk Zone was designed to determine whether a preventive home visit or multiprofessional senior group meetings could postpone deterioration in frailty if the intervention is carried out when the person is not so frail.

DESIGN AND SAMPLE

The study was a RCT with follow-ups at 1 and 2 years. A total of 459 persons (80+), still living at home, were included. Participants were independent in activities of daily life and cognitively intact.

MEASURES

Frailty was measured in two complementary ways, with the sum of eight frailty indicators and with the Mob-T Scale measuring tiredness in daily activities.

RESULTS

Both interventions showed favorable effects in postponing the progression of frailty measured as tiredness in daily activities for up to 1 year. However, neither of the two interventions was effective in postponing frailty measured with the sum of frailty indicators.

CONCLUSIONS

The results in this study show the potential of health promotion to older persons. The multiprofessional approach, including a broad spectrum of information and knowledge, might have been an important factor contributing to a more positive view of aging.

Host tropism of infectious salmon anaemia virus in marine and freshwater fish species

The aquatic orthomyxovirus infectious salmon anaemia virus (ISAV) causes a severe disease in farmed Atlantic salmon, Salmo salar L. Although some ISA outbreaks are caused by horizontal transmission of virus between farms, the source and reservoir of the virus is largely unknown and a wild host has been hypothesized. Atlantic salmon are farmed in open net-pens, allowing transmission of pathogens from wild fish and the surrounding environment to the farmed fish. In this study, a large number of fish species were investigated for ISAV host potential. For orthomyxoviruses, a specific receptor binding is the first requirement for infection; thus, the fish species were investigated for the presence of the ISAV receptor. The receptor was found to be widely distributed across the fish species. All salmonids expressed the receptor. However, only some of the cod-like and perch-like fish did, and all flat fish were negative. In the majority of the positive species, the receptor was found on endothelial cells and/or on red blood cells. The study forms a basis for further investigations and opens up the possibility for screening species to determine whether a wild host of ISAV exists.

Health-care encounters create both discontinuity and continuity in daily life when living with chronic heart failure-A grounded theory study

Living with chronic heart failure (CHF) often involves lifelong contact with health care, more or less frequently, depending on fluctuating health-generating disruptions in everyday life. To reduce the influence on continuity in life, health-care professionals should preferably focus on supporting patients in managing their daily lives, based on their perspective. The aim of this study was to describe how the interaction in health-care encounters contributes to either continuity or discontinuity in the daily life for persons with CHF. Interviews with 18 participants were carried out, using the grounded theory method, through data collection and analysis. Two core concepts were constructed from data which reveal a model that illuminates the characteristics of the encounters, the actions of health-care professionals and the normative discourse. Patient-centred agenda consists of the categories: “Experiencing a subordinate approach,” “Objectifying during the encounter” and “Expected to be compliant.” This describes how health-care professionals enhance discontinuity in daily life by using a paternalistic approach in the encounter. Person-centred agenda consists of the categories: “Experiencing an empowering approach,” “Person-centredness during the encounter” and “Expected to be capable.” It describes how participants perceive that health-care professionals enable them to deal with everyday life which enhances continuity. The findings highlight the importance of health-care professionals’ attitudes and communication in encounters with patients. Health care must be designed to support and promote patients’ own strategic thinking by strengthening their self-image to enhance continuity in everyday life. The experience of discontinuity is based on the prevailing health-care culture which focuses on disease and medical treatment and regards it as superior to the illness experience in an everyday life context. We therefore strongly suggest a paradigm shift in the health-care organisation and culture in order to support the patients in their efforts to live a meaningful, rich life, in spite of the chronic illness CHF.

Psychometric analysis of the Multidimensional Fatigue Inventory in a sample of persons treated for myocardial infarction

BACKGROUND AND PURPOSE

Fatigue after myocardial infarction is a frequent and distressing symptom in the early recovery phase. The purpose of this study is to psychometrically evaluate the Multidimensional Fatigue Inventory (MFI-20).

METHODS

The MFI-20 was evaluated using Rasch analysis.

RESULTS

The result showed that the MFI-20 can be used to obtain a global score reflecting an underlying unidimensional trait of fatigue; a transformation of the summarized raw scale scores into interval scale scores could be made. Also, 4 of the 5 original dimensions separately fitted the Rasch model.

CONCLUSIONS

Calculation of a global score increases the possibility of identifying persons experiencing fatigue after myocardial infarction, and using the MFI-20 dimension scores increases the possibility of determining each person's specific fatigue profile.

When practice precedes theory - A mixed methods evaluation of students' learning experiences in an undergraduate study program in nursing

A key area for consideration is determining how optimal conditions for learning can be created. Higher education in nursing aims to prepare students to develop their capabilities to become independent professionals. The aim of this study was to evaluate the effects of sequencing clinical practice prior to theoretical studies on student's experiences of self-directed learning readiness and students' approach to learning in the second year of a three-year undergraduate study program in nursing. 123 nursing students was included in the study and divided in two groups. In group A (n = 60) clinical practice preceded theoretical studies. In group (n = 63) theoretical studies preceded clinical practice. Learning readiness was measured using the Directed Learning Readiness Scale for Nursing Education (SDLRSNE), and learning process was measured using the revised two-factor version of the Study Process Questionnaire (R-SPQ-2F). Students were also asked to write down their personal reflections throughout the course. By using a mixed method design, the qualitative component focused on the students' personal experiences in relation to the sequencing of theoretical studies and clinical practice. The quantitative component provided information about learning readiness before and after the intervention. Our findings confirm that students are sensitive and adaptable to their learning contexts, and that the sequencing of courses is subordinate to a pedagogical style enhancing students' deep learning approaches, which needs to be incorporated in the development of undergraduate nursing programs.

Effects of chewing gum against postoperative ileus after pancreaticoduodenectomy--a randomized controlled trial

Background

Postoperative ileus is common after surgery. One non-pharmacological intervention that has shown promising results in reducing the duration of postoperative ileus is chewing gum after surgery. However, this has not been investigated in upper gastrointestinal surgery such as pancreatic surgery. Hence the aim of this study was to investigate the effects of chewing gum treatment on patients undergoing pancreaticoduodenectomy ad modum whipple due to pancreatic or periampullary cancer.

Methods

This study was conducted as a phase III trial that was terminated early. Patients diagnosed with pancreatic tumours scheduled for pancreaticoduodenectomy ad modum whipple were included. The treatment group received chewing gum postoperatively and standard care. Controls received glucose solution and standard care. Chewing gum and glucose were used four times a day during the whole hospital stay. Time to first flatus and stool was defined as the primary outcome. The secondary outcome was start with clear liquids, start with liquid diet and length of hospital stay.

Results

No statistically significant differences could be observed between the chewing gum intervention group and the control group. However, a numerical difference in mean time was observed in first flatus, first stool, start of clear fluids, and start of liquid diet and length of hospital stay in favour of the intervention group.

Conclusions

Although this study did not find statistically significant differences favouring the use of chewing gum for postoperative ileus, a positive trend was observed of a reduction of the impact of postoperative ileus among patients after pancreatic surgery. It also contributes valuable methodological experience that is important for future studies of chewing gum interventions during recovery after pancreatic surgery.

Trial registration

ClinicalTrials.gov identifier: NCT02319512, publication date 2014-12-17.

Immersion challenge with low and highly virulent infectious salmon anaemia virus reveals different pathogenesis in Atlantic salmon, Salmo salar L

The salmonid orthomyxovirus infectious salmon anaemia virus (ISAV) causes disease of varying severity in farmed Atlantic salmon, Salmo salar L. Field observations suggest that host factors, the environment and differences between ISAV strains attribute to the large variation in disease progression. Variation in host mortality and dissemination of ISAV isolates with high and low virulence (based on a previously published injection challenge) were investigated using immersion challenge. Virus dissemination was determined using real-time PCR and immunohistochemistry in several organs, including blood. Surprisingly, the low virulent virus (LVI) replicated and produced nucleoprotein at earlier time points post-infection compared to the virus of high virulence (HVI). This was particularly noticeable in the gills as indicated by different viral load profiles. However, the HVI reached a higher maximum viral load in all tested organs and full blood. This was associated with a higher mortality of 100% as compared to 20% in the LVI group by day 23 post-infection. Immersion challenge represented a more natural infection method and suggested that specific entry routes into the fish may be of key importance between ISAV strains. The results suggest that a difference in virulence is important for variations in virus dissemination and pathogenesis (disease development).

Temperature measurements of shocked silica aerogel foam

We present recent results of equation-of-state (EOS) measurements of shocked silica (SiO_{2}) aerogel foam at the OMEGA laser facility. Silica aerogel is an important low-density pressure standard used in many high energy density experiments, including the novel technique of shock and release. Due to its many applications, it has been a heavily studied material and has a well-known Hugoniot curve. This work then complements the velocity and pressure measurements with additional temperature data providing the full EOS information within the warm dense matter regime for the temperature interval of 1-15 eV and shock velocities between 10 and 40 km/s corresponding to shock pressures of 0.3-2 Mbar. The experimental results were compared with hydrodynamic simulations and EOS models. We found that the measured temperature was systematically lower than suggested by theoretical calculations. Simulations provide a possible explanation that the emission measured by optical pyrometry comes from a radiative precursor rather than from the shock front, which could have important implications for such measurements.

Sex-specific trends in 4-year survival in 37 276 men and women with acute myocardial infarction before the age of 55 years in Sweden, 1987-2006: a register-based cohort study

OBJECTIVE

To examine sex-specific trends in 4-year mortality among young patients with first acute myocardial infarction (AMI), 1987-2006.

DESIGN

Prospective cohort study.

SETTING

Sweden.

PARTICIPANTS

We identified 37 276 cases (19.4% women; age, 25-54 years) from the Swedish Inpatient Register, 1987-2006, who had survived 28 days after an AMI.

OUTCOME MEASURES

4-year mortality from all causes and standard mortality ratio (SMR).

RESULTS

From the first to last 5-year period, the absolute excess risk decreased from 1.38 to 0.50 and 1.53 to 0.59 per 100 person-years among men aged 25-44 and 45-54 years, respectively. Corresponding figures for women were a decrease from 2.26 to 1.17 and from 1.93 to 1.45 per 100 person-years, respectively. Trends for women were non-linear, decreasing to the same extent as those for men until the third period, then increasing. For the last 5-year period, the standardised mortality ratio for young survivors of AMI compared with the general population was 4.34 (95% CI 3.04 to 5.87) and 2.43 (95% CI 2.12 to 2.76) for men aged 25-44 and 45-54 years, respectively, and 13.53 (95% CI 8.36 to 19.93) and 6.42 (95% CI 5.24 to 7.73) for women, respectively. Deaths not associated with cardiovascular causes increased from 21.5% to 44.6% in men and 41.5% to 65.9% in women.

CONCLUSIONS

Young male survivors of AMI have low absolute long-term mortality rates, but these rates remain twofold to fourfold that of the general population. After favourable development until 2001, women now have higher absolute mortality than men and a 6-fold to 14-fold risk of death compared with women in the general population.

Equation of state measurements of warm dense carbon using laser-driven shock and release technique

We present a new approach to equation of state experiments that utilizes a laser-driven shock and release technique combined with spatially resolved x-ray Thomson scattering, radiography, velocity interferometry, and optical pyrometry to obtain independent measurements of pressure, density, and temperature for carbon at warm dense matter conditions. The uniqueness of this approach relies on using a laser to create very high initial pressures to enable a very deep release when the shock moves into a low-density pressure standard. This results in material at near normal solid density and temperatures around 10 eV. The spatially resolved Thomson scattering measurements facilitate a temperature determination of the released material by isolating the scattering signal from a specific region in the target. Our results are consistent with quantum molecular dynamics calculations for carbon at these conditions and are compared to several equation of state models.

Infectious salmon anaemia - pathogenesis and tropism

Infectious salmon anaemia (ISA) is a serious disease of farmed Atlantic salmon caused by the aquatic orthomyxovirus infectious salmon anaemia virus (ISAV). ISA was first detected in Norway in 1984 and was characterized by severe anaemia and circulatory disturbances. This review elucidates factors related to the pathogenesis of ISA in Atlantic salmon, the dissemination of the virus in the host and the general distribution of the 4-O-acetylated sialic acids ISAV receptor. The knowledge contributes to the understanding of this disease, and why, almost 30 years after the first detection, it is still causing problems for the aquaculture industry.

Comparison between x-ray scattering and velocity-interferometry measurements from shocked liquid deuterium

The equation of state of light elements is essential to understand the structure of Jovian planets and inertial confinement fusion research. The Omega laser was used to drive a planar shock wave in the cryogenically cooled deuterium, creating warm dense matter conditions. X-ray scattering was used to determine the spectrum near the boundary of the collective and noncollective scattering regimes using a narrow band x-ray source in backscattering geometry. Our scattering spectra are thus sensitive to the individual electron motion as well as the collective plasma behavior and provide a measurement of the electron density, temperature, and ionization state. Our data are consistent with velocity-interferometry measurements previously taken on the same shocked deuterium conditions and presented by K. Falk et al. [High Energy Density Phys. 8, 76 (2012)]. This work presents a comparison of the two diagnostic systems and offers a detailed discussion of challenges encountered.

Bright laser-driven neutron source based on the relativistic transparency of solids

Neutrons are unique particles to probe samples in many fields of research ranging from biology to material sciences to engineering and security applications. Access to bright, pulsed sources is currently limited to large accelerator facilities and there has been a growing need for compact sources over the recent years. Short pulse laser driven neutron sources could be a compact and relatively cheap way to produce neutrons with energies in excess of 10 MeV. For more than a decade experiments have tried to obtain neutron numbers sufficient for applications. Our recent experiments demonstrated an ion acceleration mechanism based on the concept of relativistic transparency. Using this new mechanism, we produced an intense beam of high energy (up to 170 MeV) deuterons directed into a Be converter to produce a forward peaked neutron flux with a record yield, on the order of 10(10)  n/sr. We present results comparing the two acceleration mechanisms and the first short pulse laser generated neutron radiograph.

Inelastic x-ray scattering from shocked liquid deuterium

The Fermi-degenerate plasma conditions created in liquid deuterium by a laser-ablation-driven shock wave were probed with noncollective, spectrally resolved, inelastic x-ray Thomson scattering employing Cl Ly(α) line emission at 2.96 keV. These first x-ray Thomson scattering measurements of the microscopic properties of shocked deuterium show an inferred spatially averaged electron temperature of 8±5  eV, an electron density of 2.2(±0.5)×10(23)  cm(-3), and an ionization of 0.8 (-0.25, +0.15). Two-dimensional hydrodynamic simulations using equation-of-state models suited for the extreme parameters occurring in inertial confinement fusion research and planetary interiors are consistent with the experimental results.

Health Is Belonging: Lived Experiences during Recovery after Pancreaticoduodenectomy

The aim of this study was to explore the lived experience of the symptoms, health, and illness reported by patients recovering after pancreaticoduodenectomy ad modum Whipple due to pancreatic or periampullary cancer. Thirteen patients with pancreatic or periampullary cancer who underwent pancreaticoduodenectomy ad modum Whipple between 2006 and 2008 were interviewed during postoperative recovery. Data were analysed using the phenomenological-hermeneutic method. The structural analysis of patient experiences revealed that recovery after pancreaticoduodenectomy was described as recapturing everyday life, being healthy, and looking to the future. Participants experienced symptoms but did not dwell on them, instead they stated that their general health was good. They strived to regain their former precancer selves and be a part of as well as contribute to the social context. Overall, the participants' view of the future was positive, and improvement in their health generated further confidence and encouragement. This study suggests that persons recovering from pancreaticoduodenectomy ad modum Whipple due to a pancreatic or periampullary tumour experience health despite postoperative symptoms. They manage their symptoms by means of different strategies and express a positive view of the future. Nurses working with such patients should adopt a person-centred approach focusing on patient perspectives, participation, and possibilities.

A sense of home in residential care

Moving into a residential care facility requires a great deal of adjustment to an environment and lifestyle entirely different from that of one's previous life. Attachment to place is believed to help create a sense of home and maintain self-identity, supporting successful adjustment to contingencies of ageing. The purpose of this study was to deepen our understanding of processes and strategies by which older people create a sense of home in residential care. Our findings show that a sense of home in residential care involves strategies related to three dimensions of the environment - attachment to place, to space and attachment beyond the institution - and that the circumstances under which older people manage or fail in creating attachment, consist of psychosocial processes involving both individual and shared attitudes and beliefs. Assuming that attachment is important to human existence regardless of age, attention must be paid to optimize the circumstances under which attachment is created in residential care, and how nursing interventions can help speed up this process due to the frail and vulnerable state of most older residents.

Multiple passage of infectious salmon anaemia virus in rainbow trout, Oncorhynchus mykiss (Walbaum), did not induce increased virus load

The infectious salmon anaemia virus (ISAV) has not been observed to cause natural disease in farmed rainbow trout, Onchorhynchus mykiss (Walbaum), but may cause high mortality in farmed Atlantic salmon, Salmo salar L. In this study, ISAV was passaged 10 times in succession by intraperitoneal injections of serum from previous passage into naïve rainbow trout. The serum viraemia was monitored by real-time qPCR. The rainbow trout in this study became infected but did not develop ISA. No clinical signs were observed in the rainbow trout in any passage, but replication of ISAV was detected from Day 4 post-infection (p.i.). Neither increased relative virus loads nor histopathological and immunohistochemical findings consistent with ISA were observed. However, the expression of interferon type I and Mx genes were slightly up-regulated in the hearts of some individual fish at day 17 p.i. Sequencing of all open reading frames in the ISAV genome of the 10th passage revealed two nucleotide mutations, one in segment 6 coding for the haemagglutinin-esterase (HE) and one in segment 1 coding for the basic polymerase 2 (PB2). The mutation in HE resulted in an amino acid substitution T/K(312) .

Measuring electron-positron annihilation radiation from laser plasma interactions

We investigated various diagnostic techniques to measure the 511 keV annihilation radiations. These include step-wedge filters, transmission crystal spectroscopy, single-hit CCD detectors, and streaked scintillating detection. While none of the diagnostics recorded conclusive results, the step-wedge filter that is sensitive to the energy range between 100 keV and 700 keV shows a signal around 500 keV that is clearly departing from a pure Bremsstrahlung spectrum and that we ascribe to annihilation radiation.

Presence and interaction of inflammatory cells in the spleen of Atlantic cod, Gadus morhua L., infected with Francisella noatunensis

Serious infectious diseases, accompanied by macrophage-dominated chronic inflammation, are common in farmed Atlantic cod. To increase knowledge relating to morphological aspects of such inflammatory responses, cod were challenged with Francisella noatunensis, an important bacterial pathogen of this fish species. Tissue and cell dynamics in the spleen were examined sequentially over 60 days. Small clusters of mainly macrophage-like cells (MLCs) staining for non-specific esterase and acid phosphatase developed with time. These foci were transiently infiltrated by pleomorphic proliferating cells of unknown nature and by granulocyte-like cells (GCLCs) staining for peroxidase and lysozyme. The latter cell type, which appeared to be resident in the red pulp of control fish, migrated into the inflammatory foci of infected fish. Cells expressing genes encoding IFN-γ and IL-8 increased in number during the study period. Bacteria were detected only in the MLCs and their number increased despite the extensive inflammation. Our results demonstrate an intimate spatial relationship in inflammatory foci between at least three cell types. The presence of GCLCs, together with MLCs, suggests pyogranulomatous inflammation as a more appropriate descriptive term than granulomatous inflammation.