| 1. |
- Wettermark, B., et al.
(författare)
-
The Nordic prescription databases as a resource for pharmacoepidemiological researcha literature review
- 2013
-
Ingår i: Pharmacoepidemiology and Drug Safety. - : Wiley. - 1053-8569 .- 1099-1557. ; 22:7, s. 691-699
-
Forskningsöversikt (refereegranskat)abstract
- Purpose All five Nordic countries have nationwide prescription databases covering all dispensed drugs, with potential for linkage to outcomes. The aim of this review is to present an overview of therapeutic areas studied and methods applied in pharmacoepidemiologic studies using data from these databases. Methods The study consists of a Medline-based structured literature review of scientific papers published during 2005-2010 using data from the prescription databases in Denmark, Finland, Iceland, Norway, and Sweden, covering 25 million inhabitants. Relevant studies were analyzed in terms of pharmacological group, study population, outcomes examined, type of study (drug utilization vs. effect of drug therapy), country of origin, and extent of cross-national collaboration. Results A total of 515 studies were identified. Of these, 262 were conducted in Denmark, 97 in Finland, 4 in Iceland, 87 in Norway, and 61 in Sweden. Four studies used data from more than one Nordic country. The most commonly studied drugs were those acting on the nervous system, followed by cardiovascular drugs and gastrointestinal/endocrine drugs. A total of 228 studies examined drug utilization and 263 focused on the effects and safety of drug therapy. Pregnant women were the most commonly studied population in safety studies, whereas prescribers' adherence to guidelines was the most frequent topic of drug utilization studies. Conclusions The Nordic prescription databases, with their possibility of record-linkage, represent an outstanding resource for assessing the beneficial and adverse effects of drug use in large populations, under routine care conditions, and with the potential for long-term follow-up. Copyright (c) 2013 John Wiley & Sons, Ltd.
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
- Zhou, Helin, et al.
(författare)
-
Close electric field changes associated with upward-initiated lightning at the Gaisberg Tower
- 2011
-
Ingår i: 2011 International Symposium on Lightning Protection, XI SIPDA 2011. - 9781457718977 ; , s. 87-90
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- We examine in detail the simultaneous lightning current waveforms, close electric field changes, and lighting location system data for upward lightning discharges initiated from the Gaisberg Tower (GBT) from 2005 to 2009. Out of 205 upward flashes, we find that most of upward flashes (179/205 or 87%) are initiated at the tower top without any nearby preceding discharge activity, 26 flashes (13%) are initiated by nearby triggering lightning discharges, including 10 positive cloud-to-ground lightning, 1 negative cloud-to-ground lightning, and 15 cloud discharges. The possible reasons for self-triggered upward flashes dominating at the GBT would be the field enhancement due to the Gaisberg Mountain above 800 m of the surrounding terrain of the city of Salzburg and low cloud base during cold season.
|
|
| 7. |
- Zhou, Helin, et al.
(författare)
-
Mixed mode of charge transfer to ground for initial continuous current pulses in upward lightning
- 2011
-
Ingår i: 2011 7th Asia-Pacific International Conference on Lightning (APL). ; , s. 677-681
-
Konferensbidrag (refereegranskat)abstract
- In this paper, we discuss properties of initial continuous current (ICC) pulses superimposed on the slow varying initial stage current in upward flashes initiated from the Gaisberg Tower (GBT) based on simultaneous current, near/far electric field measurements. ICC pulses are usually associated with M-component mode of charge transfer to ground, if only one branch of the lightning channel is active. However, there are several cases in which ICC pulses involve a predominantly leader/return-stroke mode of charge transfer to ground in a new channel that connects to the old channel carrying continuous current. With the help of high-speed video camera records, we find that this mixed mode of charge transfer for ICC pulses, leader-return stroke in one channel and continuous current in another channel, occurring simultaneously during the initial stage current in upward lightning from tall towers is very common. This is in contrast to triggered-lightning where usually only one channel is dominant and ICC pulses are associated predominantly with M-component mode of charge transfer. Also, ICC pulses with mixed-mode of charge transfer have shorter risetimes, larger peaks, and shorter half-peak widths.
|
|
| 8. |
- Zhu, B., et al.
(författare)
-
Estimation of channel characteristics of narrow bipolar events based on the transmission-line model
- 2010
-
Ingår i: Journal of Geophysical Research. - 0148-0227 .- 2156-2202. ; 115:19, s. D19105-
-
Tidskriftsartikel (refereegranskat)abstract
- Narrow bipolar event (NBE) is a distinct class of intracloud lightning discharge, which is associated with the strongest radio frequency emissions and produces typical narrow bipolar radiation field waveforms. On the basis of the transmission-line model, we introduce a direct technique to measure the time taken by the current front to propagate along the channel from distant radiation field pulses; the channel length of the NBE can then be estimated by multiplying this time by an assumed propagation speed. Our method involves integrating over the initial half cycle of narrow bipolar waveform of the NBE. The ratio of the integral result to the initial peak amplitude makes a good approximation to the time taken by the current front to travel along the channel, even though the current amplitude suffers heavy attenuation along the propagating channel. This method can be applied to all NBEs which produce narrow bipolar radiation field waveforms. Besides, if both the far radiation field and the near-electrostatic field measurements were available, one could combine the method here and that of Eack (2004) to obtain the channel length of the NBE.
|
|
