Altitude calibration of the Tromsø medium frequency radar

This publication is the inaugural report in the series Tromsø Geophysical Observatory Reports.Although the Tromsø Medium Frequency Radar situated at Ramfjordmoen, Norway (69°N, 19°E) has been operating for over a quarter of a century, no definitive altitude calibration has ever been documented using independent measurements of the same atmosphere. Here we perform calibrations using the recently installed (November 2003) Nippon/Norway Tromsø Meteor Radar by identifying wind features in the same volume. We also perform an independent check using oscilloscope measurements supplemented by an acoustic delay line

Mental distress, help seeking, and use of health services among university students. The SHoT-study 2018, Norway

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The relationship between headache-attributed disability and lost productivity: 3 Attack frequency is the dominating variable.

BACKGROUND: In an earlier paper, we examined the relationship between headache-attributed disability, measured as proportion of time in ictal state, and lost productivity. In a linear model, we found positive and significant associations with lost paid worktime, lost household worktime and total lost productivity (paid + household), but with high variance, which was increased when headache intensity was introduced as a factor. We speculated that analyses based on headache frequency alone as the independent variable, eliminating both the subjectivity of intensity estimates and the uncertainties of duration, might show stronger associations. METHODS: Focusing on migraine, we used individual participant data from 16 countries surveyed either in population-based studies or in the Eurolight project. These data included frequency (headache days/month), usual attack duration (hours), usual headache intensity ("not bad", "quite bad", "very bad") and lost productivity from paid and household work according to enquiries using the Headache-Attributed Lost Time (HALT) questionnaire. We used multiple linear regressions, calculating regression equations along with unstandardized and standardized regression coefficients. We made line and bar charts to visualize relationships. RESULTS: Both frequency and intensity were significant predictors of lost productivity in all multiple linear regressions, but duration was a non-significant predictor in several of the regressions. Predicted productivity in paid work decreased among males by 0.75-0.85 days/3 months for each increase of 1 headache day/month, and among females by 0.34-0.53 days/3 months. In household chores, decreases in productivity for each added day/month of headache were more similar (0.67-0.87 days/3 months among males, 0.83-0.89 days/3 months among females). Visualizations showed that the impact of duration varied little across the range of 2-24 h. The standardized regression coefficients demonstrated that frequency was a much better predictor of lost productivity than intensity or duration. CONCLUSION: In the relationship between migraine-attributed impairment (symptom burden) and lost productivity, frequency (migraine days/month) is the dominating variable - more important than headache intensity and far more important than episode duration. This has major implications for current practice in headache care and for health policy and health-resource investment. Preventative drugs, grossly underutilized in current practice, offer a high prospect of economic benefit (cost-saving), but new preventative drugs are needed with better efficacy and/or tolerability

Analiza prijelazne pojave adaptivnih filtara primjenom općeg radnog okvira

Employing a recently introduced framework in which a large number of adaptive filter algorithms can be viewed as special cases, we present a generalized transient analysis. An important implication of this is that while the theoretical analysis is performed for a generic filter coefficient update equation the results are directly applicable to a large range of adaptive filter algorithms simply by specifying some parameters of this generic filter coefficient update equation. In particular we point out that theoretical learning curves for the Least Mean Square (LMS), Normalized Least Mean Square (NLMS), the Affine Projection Algorithm (APA) and its relatives, as well as the Recursive Least Squares (RLS) algorithm are obtained as special cases of a general result. Subsequently, the recently introduced Fast Euclidian Direction Search (FEDS) algorithms as well as the Pradhan-Reddy subband adaptive filter (PRSAF) are used as non-trivial examples when we demonstrate the usefulness and versatility of the proposed approach to adaptive filter transient analysis through an experimental evaluation.U radu se predstavlja poopćena analiza prijelaznih pojava adaptivnih filtara, koja se zasniva na primjeni nedavno predstavljenog radnog okvira koji velik broj raznih algoritama adaptivnih filtara promatra kao specijalne slučajeve. Važna posljedica toga je da su rezultati, iako se teoretska analiza provodi na generičkoj jednadžbi za osvježavanje koeficijenta filtra, izravno primjenjivi na razne algoritme adaptivnih filtara jednostavnom specificikacijom nekih parametara generičke jednadžbe za osvježavanje koeficijenata filtra. Posebno se naglašava da su teoretske krivulje učenja za algoritam najmanjih kvadrata (LMS), normalizirani algoritam najmanjih kvadrata (NLMS), afini projekcijski algoritam (APA) i njemu srodnih algoritama, kao i za rekurzivni algoritam najmanjih kvadrata (RLS) dobivene kao posebni slučajevi poopćenog rješenja. Potom se nedavno predstavljeni algoritmi brze euklidske usmjerene pretrage (FEDS) te Pradhan-Reddy pojasni adaptivni filtar (PRSAF) koriste kao netrivijalni primjeri za dokazivanje korisnosti i univerzalnosti predloženog pristupa analizi prijelaznih pojava adaptivnih filtara kroz eksperimentalnu evaluaciju

A Simplified Normalized Subband Adaptive Filter (NSAF) with NLMS-like complexity

The Normalized Subband Adaptive Filter (NSAF) is a popular algorithm exhibiting moderate computational complexity and enhanced convergence speed relative to the ubiquitous Normalized Least Mean Square (NLMS) algorithm. Traditionally, the NSAF has made use of sophisticated perfect reconstruction (PR) filter banks and a block updating scheme, in which the adaptive filter vector is updated once every N samples, with N being equal to the number of subbands. Here we argue, first from a theoretical point of view, that an extremely simple two band filter bank with the simplest possible length 2 FIR filters, {1, −1} and {1, 1}, can be successfully used either with a sample by sample adaptive filter update, or with a block update performed for every second input signal sample. We demonstrate that this scheme actually works well through simulations. In short we obtain better convergence performance than the NLMS with a (multiplicative) computationally complexity proportional to 2M , M being the length of the adaptive filter to be identified, with the block update and even better performance if we are willing to accept a computational complexity proportional to 4M

‘I wanted to go, but they said wait’: Mothers’ bargaining power and strategies in careseeking for ill newborns in Ethiopia

Introduction To prevent the 2.6 million newborn deaths occurring worldwide every year, health system improvements and changes in care-taker behaviour are necessary. Mothers are commonly assumed to be of particular importance in care-seeking for ill babies; however, few studies have investigated their participation in these processes. This study explores mothers’ roles in decision making and strategies in care-seeking for newborns falling ill in Ethiopia. Methods A qualitative study was conducted in Butajira, Ethiopia. Data were collected during the autumn of 2015 and comprised 41 interviews and seven focus group discussions. Participants included primary care-takers who had experienced recent newborn illness or death, health care workers and community members. Data were analysed using thematic analysis. Results Choices about whether, where and how to seek care for ill newborns were made through cooperation and negotiation among household members. Mothers were considered the ones that initially identified or recognised illness, but their actual opportunities to seek care were bounded by structural and cultural constraints. Mothers’ limited bargaining power, contained by financial resources and gendered decision making, shaped their roles in care-seeking. We identified three strategies mothers took on in decision making for newborn illness: (a) acceptance and adaptation (to the lack of options), (b) negotiation and avoidance of advice from others, and (c) active care-seeking and opposition against the husband’s or community’s advice. Conclusion While the literature on newborn health and parenting emphasizes the key role of mothers in care-seeking, their actual opportunities to seek care are shaped by factors commonly beyond their control. Efforts to promote care-seeking for ill children should recognise that mothers’ capabilities to make decisions are embedded in gendered social processes and financial power structures. Thus, policies should not only target individual mothers, but the wider decision making group, including the head of households and extended family.publishedVersio