ABSTRACT
The substorm current wedge (SCW) is a fundamental component of geomagnetic substorms. Models tend to describe the SCW as a simple line current flowing into the ionosphere toward dawn and out of the ionosphere toward dusk, linked by a westward electrojet. We use multispacecraft observations from perigee passes of the Cluster 1 and 4 spacecraft during a substorm on 15 January 2010, in conjunction with ground-based observations, to examine the spatial structuring and temporal variability of the SCW. At this time, the spacecraft traveled east-west azimuthally above the auroral region. We show that the SCW has significant azimuthal substructure on scales of 100 km at altitudes of 4000-7000 km. We identify 26 individual current sheets in the Cluster 4 data and 34 individual current sheets in the Cluster 1 data, with Cluster 1 passing through the SCW 120-240 s after Cluster 4 at 1300-2000 km higher altitude. Both spacecraft observed large-scale regions of net upward and downward field-aligned current, consistent with the large-scale characteristics of the SCW, although sheets of oppositely directed currents were observed within both regions. We show that the majority of these current sheets were closely aligned to a north-south direction, in contrast to the expected east-west orientation of the preonset aurora. Comparing our results with observations of the field-aligned current associated with bursty bulk flows (BBFs), we conclude that significant questions remain for the explanation of SCW structuring by BBF-driven "wedgelets." Our results therefore represent constraints on future modeling and theoretical frameworks on the generation of the SCW. KEY POINTS: The substorm current wedge (SCW) has significant azimuthal structureCurrent sheets within the SCW are north-south alignedThe substructure of the SCW raises questions for the proposed wedgelet scenario.
ABSTRACT
The extent of where magnetic reconnection (MR), the dominant process responsible for energy and plasma transport into the magnetosphere, operates across Earth's dayside magnetopause has previously been only indirectly shown by observations. We report the first direct evidence of X-line structure resulting from the operation of MR at each of two widely separated locations along the tilted, subsolar line of maximum current on Earth's magnetopause, confirming the operation of MR at two or more sites across the extended region where MR is expected to occur. The evidence results from in-situ observations of the associated ion and electron plasma distributions, present within each magnetic X-line structure, taken by two spacecraft passing through the active MR regions simultaneously.
ABSTRACT
In our postmortem examinations of patients in the canton of Thurgau from May 1989 through December 1991 we found a cholelithiasis or a condition after a cholecystectomy of gallstones in 44% of the women and 23% of the men. While gallstones were found in only 11% of the women and 7% of the men up to age 50, half of all women and every third man in the age group over 90 had gallstones. Among the gallstone carriers, 8% of the women and 2.5% of the men had developed a gall bladder--gall duct carcinoma. Where a liver cirrhosis was present, gallstones occurred at nearly the same rate in both sexes (45%/44%). 33% of the persons with gallstones had a solitary stone, and 31% had more than 10 stones. More than a third of all stones had a cholesterol content of more than 80%, and every seventh stone had a bilirubin content higher than 80%. The calcium content of more than 40% of the stones exceeded 5%. The examination for bilirubin can be easily performed with some exercise by means of the bilirubin test field on the urine sticks supplied by the Boehringer Mannheim company.
