Ionospheric measurements of relative coronal brightness during the total solar eclipses of 11 August, 1999 and 9 July, 1945

Swept-frequency (1-10 MHz) ionosonde measurements were made at Helston, Cornwall (50 degrees 06'N, 5 degrees 18'W) during the total solar eclipse on August 11, 1999. Soundings were made every three minutes. We present a method for estimating the percentage of the ionising solar radiation which remains unobscured at any time during the eclipse by comparing the variation of the ionospheric E-layer with the behaviour of the layer during a control day. Application to the ionosonde date for II August, 1999, shows that the flux of solar ionising radiation fell to a minimum of 25 +/- 2% of the value before and after the eclipse. For comparison, the same technique was also applied to measurements made during the total solar eclipse of 9 July, 1945, at Sormjole (63 degrees 68'N, 20 degrees 20'E) and yielded a corresponding minimum of 16 +/- 2%. Therefore the method can detect variations in the fraction of solar emissions that originate from the unobscured corona and chromosphere. We discuss the differences between these two eclipses in terms of the nature of the eclipse, short-term fluctuations, the sunspot cycle and the recently-discovered long-term change in the coronal magnetic field.

Evidence of chromosome fusion in Gymnotus sylvius Albert & Fernandes-Matoli, 1999 (Teleostei: Gymnotiformes) detected by telomeric probes and R-banding

Gymnotus cf. carapo and Gynznotus sylvius are two fish species inhabiting the Upper Parana River Basin, presenting respectively 2n =54 and 2n = 40 chromosomes. In the present cytogenetic analysis, R-banding and telomere-sequence hybridization were carried out in order to determine the possible relationship between the karyotipes of these two species. Incorporation bands (R-bands) obtained for the two species allowed the identification of chromosome similarities, showing to be an usefull alternative to the G-banding methods, which fail in producing satisfying results in most of analyzed fish species. This approach, associated with the hybridization of telomeric sequences, permited to identify chromosomal rearrangements that could be used as indicators of karyotypic evolution within the group. In the present case, telomeric sequences were detected in the centromeric region of two metacentric chromosome pairs of Gymnotus sylvius. The results obtained after hybridization with the telomere sequences, coupled with the chromosome homeologies detected by R-banding, showed that G. cf carapo and G. sylvius should present a common ancestor, and this may also be corroborated by the similarities found in three chromosome pairs, that seem to have been conserved during the evolution of the two species. Based on the data here presented we propose that G. sylvius may have undergone a recent process of chromosome fusion that resulted in the diminution of its chromosome number.

Characterization of the optical properties of atmospheric aerosols in Amazonia from long-term AERONET monitoring (1993-1995 and 1999-2006)

We present a new climatology of atmospheric aerosols (primarily pyrogenic and biogenic) for the Brazilian tropics on the basis of a high-quality data set of spectral aerosol optical depth and directional sky radiance measurements from Aerosol Robotic Network (AERONET) Cimel Sun-sky radiometers at more than 15 sites distributed across the Amazon basin and adjacent Cerrado region. This network is the only long-term project (with a record including observations from more than 11 years at some locations) ever to have provided ground-based remotely-sensed column aerosol properties for this critical region. Distinctive features of the Amazonian area aerosol are presented by partitioning the region into three aerosol regimes: southern Amazonian forest, Cerrado, and northern Amazonian forest. The monitoring sites generally include measurements from the interval 1999-2006, but some sites have measurement records that date back to the initial days of the AERONET program in 1993. Seasonal time series of aerosol optical depth (AOD), angstrom ngstrom exponent, and columnar-averaged microphysical properties of the aerosol derived from sky radiance inversion techniques (single-scattering albedo, volume size distribution, fine mode fraction of AOD, etc.) are described and contrasted for the defined regions. During the wet season, occurrences of mineral dust penetrating deep into the interior were observed.

Ramprogram solfångarutveckling och systematik. FoU 1997-1999. Slutrapport BFR projekt 19960605

Man kan förbättra energibesparingen på årsbasis för ett traditionellt svenskt kombisolvärmesystem från knappt 20 % för ett referenssystem till över 25 %. Alla de studerade systemen har 10 m2 solfångare, lika stor tank, och samma värme- och tappvarmvattenlast. Skillnaderna består endast i systemutformning. Arbetet har utförts genom mätningar i värmelaboratorium och simuleringsberäkningar. Inom området optisk design av solenergisystem har metoder utvecklats för: - analys av solinstråningens himmelsfordelning och asymmetriska årsfordelning - optimering av sollangare med reflektorer - optimering av solceller med tillsatsreflektorer Programmet PRESIM, grafisk indatabehandlare till simuleringsprogrammet TRNSYS, har vidareutvecklats i linje med användarnas önskemål, men förutsättningarna för fortsatt utveckling har försämrats. En förbättrad version, delvis finansierad av Statens energimyndighet och anpassad till TRNSYS 15.0, kommer att släppas under år 2000, men därefter kommer aktiviteten att ligga på en lägre nivå.

The panorama and outcomes of reported pregnancies within a well defined population in rural Vietnam 1999-2004

Background Pregnancy outcomes in the general population are important public health indicators. Purpose The overall aim of this study was to investigate the outcomes of reported pregnancies within a well-defined population, to identify risk groups for adverse pregnancy outcomes, and to suggest preventive measures. Method A prospective population-based cohort study of pregnant women in Bavi district, Vietnam between 1 January 1999 and 30 June 2004. Results Pregnancy outcome was reported for 5,259 cases; 4,152 (79%) resulted in a live birth, 67 (1.3%) in a stillbirth, 733 (14%) in an induced abortion, and 282 (5.4%) in a spontaneous abortion. There was an increased risk of home delivery for women from ethnic minorities (OR?=?1.85; 95%CI?=?1.06–3.24) or with less than 6 years of schooling (OR?=?7.36; 95%CI?=?3.54–15.30). The risk of stillbirth was increased for ethnic minorities (OR?=?6.34; 95%CI?=?1.33–30.29) and women delivering at home (OR?=?6.81; 95%CI?=?2.40–19.30). The risk of induced abortion increased with maternal age. Conclusion Our findings emphasize the public health significance of access to adequate family planning, counselling, and maternal health care for all women. Policies should specifically target women from high-risk groups.

Do we need a new classification system for female sexual dysfunction? A comment on the 1999 consensus classification system.

This Article does not have an abstract.