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The Stardust â a successful encounter with the remarkable comet Wild 2
On January 2, 2004 the Stardust spacecraft completed a close flyby of comet Wild2 (P81). Flying at a relative speed of 6.1 km/s within 237km of the 5 km nucleus, the spacecraft took 72 close-in images, measured the flux of impacting particles and did TOF mass spectrometry
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Target loads of atmospheric sulfur and nitrogen deposition for protection of acid sensitive aquatic resources in the Adirondack Mountains, New York
The dynamic watershed acid-base chemistry model of acidification of groundwater in catchments (MAGIC) was used to calculate target loads (TLs) of atmospheric sulfur and nitrogen deposition expected to be protective of aquatic health in lakes in the Adirondack ecoregion of New York. The TLs were calculated for two future dates (2050 and 2100) and three levels of protection against lake acidification (acid neutralizing capacity (ANC) of 0, 20, and 50 ÎŒeq Lâ»Âč). Regional sulfur and nitrogen deposition estimates were combined with TLs to calculate exceedances. Target load results, and associated exceedances, were extrapolated to the regional population of Adirondack lakes. About 30% of Adirondack lakes had simulated TL of sulfur deposition less than 50 meq mâ»ÂČ yr to protect lake ANC to 50 ÎŒeq Lâ»Âč. About 600 Adirondack lakes receive ambient sulfur deposition that is above this TL, in some cases by more than a factor of 2. Some critical criteria threshold values were simulated to be unobtainable in some lakes even if sulfur deposition was to be decreased to zero and held at zero until the specified endpoint year. We also summarize important lessons for the use of target loads in the management of acid-impacted aquatic ecosystems, such as those in North America, Europe, and Asia
Phylogeny of the Australian Solanum dioicum group using seven nuclear genes: Testing Symonâs fruit and seed dispersal hypotheses.
The dioecious and andromonoecious Solanum taxa (the âS. dioicum groupâ) of the Australian Monsoon Tropics have been the subject of phylogenetic and taxonomic study for decades, yet much of their basic biology is still unknown. This is especially true for plant-animal interactions, including the influence of fruit form and calyx morphology on seed dispersal. We combine field/greenhouse observations and specimen-based study with phylogenetic analysis of seven nuclear regions obtained via a microfluidic PCR-based enrichment strategy and high-throughput sequencing, and present the first species-tree hypothesis for the S. dioicum group. Our results suggest that epizoochorous trample burr seed dispersal (strongly linked to calyx accrescence) is far more common among Australian Solanum than previously thought and support the hypothesis that the combination of large fleshy fruits and endozoochorous dispersal represents a reversal in this study group. The general lack of direct evidence related to biotic dispersal (epizoochorous or endozoochorous) may be a function of declines and/or extinctions of vertebrate dispersers. Because of this, some taxa might now rely on secondary dispersal mechanisms (e.g. shakers, tumbleweeds, rafting) as a means to maintain current populations and establish new ones
Bronchiectasis Rheumatoid Overlap Syndrome Is an Independent Risk Factor for Mortality in Patients With Bronchiectasis:A Multicenter Cohort Study
BACKGROUND: This study assessed if bronchiectasis (BR) and rheumatoid arthritis (RA), when manifesting as an overlap syndrome (BROS), were associated with worse outcomes than other BR etiologies applying the Bronchiectasis Severity Index (BSI).
METHODS: Data were collected from the BSI databases of 1,716 adult patients with BR across six centers: Edinburgh, United Kingdom (608 patients); Dundee, United Kingdom (n = 286); Leuven, Belgium (n = 253); Monza, Italy (n = 201); Galway, Ireland (n = 242); and Newcastle, United Kingdom (n = 126). Patients were categorized as having BROS (those with RA and BR without interstitial lung disease), idiopathic BR, bronchiectasis-COPD overlap syndrome (BCOS), and "other" BR etiologies. Mortality rates, hospitalization, and exacerbation frequency were recorded.
RESULTS: A total of 147 patients with BROS (8.5% of the cohort) were identified. There was a statistically significant relationship between BROS and mortality, although this relationship was not associated with higher rates of BR exacerbations or BR-related hospitalizations. The mortality rate over a mean of 48 months was 9.3% for idiopathic BR, 8.6% in patients with other causes of BR, 18% for RA, and 28.5% for BCOS. Mortality was statistically higher in patients with BROS and BCOS compared with those with all other etiologies. The BSI scores were statistically but not clinically significantly higher in those with BROS compared with those with idiopathic BR (BSI mean, 7.7 vs 7.1, respectively; P < .05). Patients with BCOS had significantly higher BSI scores (mean, 10.4), Pseudomonas aeruginosa colonization rates (24%), and previous hospitalization rates (58%).
CONCLUSIONS: Both the BROS and BCOS groups have an excess of mortality. The mechanisms for this finding may be complex, but these data emphasize that these subgroups require additional study to understand this excess mortality
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