Hourly resolution forward curves for power: statistical modeling meets market fundamentals

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Agile Ways of Working: A Team Maturity Perspective

With the agile approach to managing software development projects comes an increased dependability on well functioning teams, since many of the practices are built on teamwork. The objective of this study was to investigate if, and how, team development from a group psychological perspective is related to some work practices of agile teams. Data were collected from 34 agile teams (200 individuals) from six software development organizations and one university in both Brazil and Sweden using the Group Development Questionnaire (Scale IV) and the Perceptive Agile Measurement (PAM). The result indicates a strong correlation between levels of group maturity and the two agile practices \emph{iterative development} and \emph{retrospectives}. We, therefore, conclude that agile teams at different group development stages adopt parts of team agility differently, thus confirming previous studies but with more data and by investigating concrete and applied agile practices. We thereby add evidence to the hypothesis that an agile implementation and management of agile projects need to be adapted to the group maturity levels of the agile teams

Atrial high rate episodes predict clinical outcome in patients with cardiac resynchronization therapy

OBJECTIVES: Up to 50% of patients qualified for cardiac resynchronization therapy (CRT) have documented atrial fibrillation (AF) prior to CRT-implantation. This finding is associated with worse prognosis but few studies have evaluated the importance of post-implant device-detected AF. This study aimed to assess the prognostic impact of device-detected atrial high rate episodes (AHRE), as a surrogate for atrial fibrillation (AF).DESIGN: Data was retrospectively obtained from consecutive patients receiving CRT. Baseline clinical data and data from CRT device-interrogations, performed at a median of 12.2 months after CRT-implantation, were evaluated with regard to prediction of the composite endpoint of death, heart transplant or appropriate shock therapy. Median follow-up time was 51 months post-implant.RESULTS: The study included 377 patients. Preoperative AF was present in 49% and associated with worse outcome. The cumulative burden of AHRE at 12 months post-implant was an independent predictor of the primary endpoint. During the first 12 months after CRT-implantation, AHRE were detected in 25% of the patients with no preoperative diagnosis of AF. This finding was not associated with worse outcome.CONCLUSIONS: In CRT recipients, the cumulative burden of AHRE during first year of follow-up was associated with worse long-term clinical outcome. Prospective trials are needed to determine if a rhythm control strategy is to be preferred in patients with CRT

Distributed Massive MIMO via all-Digital Radio Over Fiber

A crucial challenge in the implementation of distributed massive multiple-input multiple-output (MIMO) architectures is to provide phase coherence while, at the same time, limit the complexity of the remote-radio heads (RRHs), which is important for cost-efficient scalability. To address this challenge, we present in this paper a phase-coherent distributed MIMO architecture, based on off-the-shelf, low-cost components. In the proposed architecture, up- and down-conversion are carried out at the central unit (CU). The RRHs are connected to the CU by means of optical fibers carrying oversampled radio-frequency (RF) 1-bit signals. In the downlink, the 1-bit signal is generated via sigma-delta modulation. At the RRH, the RF signal is recovered from the 1-bit signal through a bandpass filter and a power amplifier, and then fed to an antenna. In the uplink, the 1-bit signal is generated by a comparator whose inputs are the low-noise-amplified received RF signal and a suitably designed dither signal. The performance of the proposed architecture is evaluated with satisfactory results both via simulation and measurements from a testbed

Self-Service Business Intelligence: Konsekvenserna av flexibilitet

Dagens föränderliga och dynamiska marknad har lett till att organisationer tvingas vara flexibla för att snabbare kunna fatta beslut och anpassa sig. Vidare har detta lett till en förändring inom Business Intelligence (BI), där en nyare lösning kallad Self-Service Business Intelligence (SSBI) har vuxit fram. SSBI syftar huvudsakligen till att förbättra beslutsfattande i organisationer genom att göra processen för beslutsfattande snabbare och ge användare mer flexibilitet. Flexibiliteten ger användare möjlighet att betjäna sig själva i arbetet för att ta fram beslutsunderlag. Uppsatsen argumenterar för att den flexibilitet som SSBI är tänkt att medföra inte kommer utan oproblematiska konsekvenser. Uppsatsen presenterar teoretiska förhållningssätt till SSBI som beskriver möjligheter och utmaningar med SSBI. Teorin jämförs därefter med empiri som utvunnits från sex intervjuer med olika leverantörer av BI-lösningar. Studien har identifierat att för att uppnå ändamålsenlig flexibilitet krävs det att datakvaliteten och tillförlitligheten säkerställs och att adekvat utbildning ges. Uppsatsen ifrågasätter därför begreppet “self-service” eftersom den eftersträvade effekten att låta användare betjäna sig själva inte sker utan att konsekvenserna av flexibilitet beaktas

Rheumatoid arthritis is getting less frequent—results of a nationwide population-based cohort study

Objectives: The objectives of this study were to examine changes in incidence and prevalence of RA between 1990 and 2014, and to explore if there is any geographic variation in incidence and prevalence of RA in the UK Methods: Design Prospective cohort study Setting Primary care Participants People contributing acceptable data to Clinical Practice Research Datalink (CPRD) between 01/01/1990 and 31/12/2014 were included. Read codes were used to identify RA cases ≥18 years in age. Outcomes Prevalence and incidence rates for each year standardised to the 2014 population. Region specific incidence and prevalence of RA for the year 2014 standardized to the overall population. Results: The incidence and prevalence of RA was 3.81 per 10,000 person-years and 0.67% respectively in 2014. The annual incidence of RA reduced by -1.6%(-0.8% to - 2.5%) between 1990 and 2014, with significant joinpoints at 1994 and 2002. The prevalence of RA increased by 3.7%(3.2% to 4.1%)/year from 1990 to 2005; and reduced by -1.1%(-2.0% to -0.2%)/year between 2005 and 2014. There were significant differences in the occurrence of RA throughout different regions of the UK, with highest incidence in East Midlands, Yorkshire and Humber; and highest prevalence in North East, and Yorkshire and Humber. Conclusion: The incidence of RA is decreasing, with a reduction in prevalence in recent years. There is significant geographic variation in occurrence of RA in UK. Further research is required to identify the reasons underlying this phenomenon so that public-health interventions can be designed to further reduce the incidence of RA

Detailed Analysis of Variants in FTO in Association with Body Composition in a Cohort of 70-Year-Olds Suggests a Weakened Effect among Elderly

The rs9939609 single-nucleotide polymorphism (SNP) in the fat mass and obesity (FTO) gene has previously been associated with higher BMI levels in children and young adults. In contrast, this association was not found in elderly men. BMI is a measure of overweight in relation to the individuals' height, but offers no insight into the regional body fat composition or distribution.To examine whether the FTO gene is associated with overweight and body composition-related phenotypes rather than BMI, we measured waist circumference, total fat mass, trunk fat mass, leg fat mass, visceral and subcutaneous adipose tissue, and daily energy intake in 985 humans (493 women) at the age of 70 years. In total, 733 SNPs located in the FTO gene were genotyped in order to examine whether rs9939609 alone or the other SNPs, or their combinations, are linked to obesity-related measures in elderly humans.Cross-sectional analysis of the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) cohort.Neither a single SNP, such as rs9939609, nor a SNP combination was significantly linked to overweight, body composition-related measures, or daily energy intake in elderly humans. Of note, these observations hold both among men and women.Due to the diversity of measurements included in the study, our findings strengthen the view that the effect of FTO on body composition appears to be less profound in later life compared to younger ages and that this is seemingly independent of gender

Understanding how excess lead iodide precursor improves halide perovskite solar cell performance

The presence of excess lead iodide in halide perovskites has been key for surpassing 20% photon-to-power conversion efficiency. To achieve even higher power conversion efficiencies, it is important to understand the role of remnant lead iodide in these perovskites. To that end, we explored the mechanism facilitating this effect by identifying the impact of excess lead iodide within the perovskite film on charge diffusion length, using electron-beam-induced current measurements, and on film formation properties, from grazing-incidence wide-angle X-ray scattering and high-resolution transmission electron microscopy. Based on our results, we propose that excess lead iodide in the perovskite precursors can reduce the halide vacancy concentration and lead to formation of azimuthal angle-oriented cubic alpha-perovskite crystals in-between 0 degrees and 90 degrees. We further identify a higher perovskite carrier concentration inside the nanostructured titanium dioxide layer than in the capping layer. These effects are consistent with enhanced lead iodide-rich perovskite solar cell performance and illustrate the role of lead iodide