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Evidence from the northwestern Venezuelan Andes for extraterrestrial impact: The black mat enigma
Mahaney, W.C.,Kalm, V.,Krinsley, D.H.,Tricart, P.,Schwartz, S.,Dohm, J.,Kim, K.J.,Kapran, B.,Milner, M.W.,Beukens, R.,Boccia, S.,Hancock, R.G.V.,Hart, K.M.,Kelleher, B. Elsevier 2010 Geomorphology Vol.116 No.1
<P><B>Abstract</B></P><P>A carbon-rich black layer encrusted on a sandy pebbly bed of outwash in the northern Venezuelan Andes, previously considered the result of an alpine grass fire, is now recognized as a ‘black mat’ candidate correlative with Clovis Age sites in North America, falling within the range of ‘black mat’ dated sites (~12.9ka cal BP). As such, the bed at site MUM7B, which dates to <11.8ka <SUP>14</SUP>C years BP (raw dates) and appears to be contemporaneous with the Younger Dryas (YD) cooling event, marks a possibly much more extensive occurrence than previously identified. No fossils (megafauna) or tool assemblages were observed at this newly identified candidate site (3800a.m.s.l.), as in the case of the North American sites. Here, evidence is presented for an extraterrestrial impact event at ~12.9ka. The impact-related Andean bed, located ~20cm above 13.7–13.3ka cal BP alluvial and glaciolacustrine deposits, falls within the sediment characteristics and age range of ‘black mat’ dated sites (~12.9ka cal BP) in North America. Site sediment characteristics include: carbon, glassy spherules, magnetic microspherules, carbon mat ‘welded’ onto coarse granular material, occasional presence of platinum group metals (Rh and Ru), planar deformation features (pdfs) in fine silt-size fragmental grains of quartz, as well as orthoclase, and monazite (with an abundance of Rare Earth Elements—REEs). If the candidate site is ‘black mat’, correlative with the ‘black mat’ sites of North America, such an extensive occurrence may support the hypothesized airburst/impact over the Laurentide Glacier, which led to a reversal of Allerød warming and the onset of YD cooling and readvance of glaciers. While this finding does not confirm such, it merits further investigation, which includes the reconnaissance for additional sites in South America. Furthermore, if confirmed, such an extensive occurrence may corroborate an impact origin.</P>
Gitte S. Jensen,Aaron N. Hart,Lue Ann Zaske,Kelly M. Patterson,Christian Drapeau 한국식품영양과학회 2007 Journal of medicinal food Vol.10 No.3
The present research was designed to study the effects of an extract from the edible cyanophyta Aphanizomenonflos-aquaeon human natural killer (NK) cells. We have previously shown, using a double-blind randomized placebo-con-trolled crossover design, that ingestion of 1.5 g of dried whole A. flos-aquaeresulted in a transient reduction in peripheralblood NK cells in 21 healthy human volunteers, suggesting increased NK cell homing into tissue. We have now identified anextract from A. flos-aquae(AFAe) that directly activates NK cells in vitroand modulates the chemokine receptor profile. NKcell activation was evaluated by expression of CD25 and CD69 on CD3. CD56. cells after 18 hours. Changes in CXCR3and CXCR4 chemokine receptor expression after 560 minutes were evaluated by immunostaining and flow cytometry. AFAeinduced the expression of CD69 on CD3. CD56. NK cells, induced CD25 expression on 25% of these cells, and acted insynergy with interleukin 2. NK cells enriched by RosetteSep?? (StemCell Technologies Inc., Vancouver, BC, Canada) werenot activated by AFAe, indicating that the NK activation was dependent on other cells such as monocytes. The low-molecu-lar-weight fraction . 5,000 of AFAe was responsible for the most robust NK cell activation, suggesting novel compounds dif-