KOI-126: a triply eclipsing hierarchical triple with two low-mass stars

The Kepler spacecraft has been monitoring the light from 150,000 stars in its primary quest to detect transiting exoplanets. Here, we report on the detection of an eclipsing stellar hierarchical triple, identified in the Kepler photometry. KOI-126 [A, (B, C)], is composed of a low-mass binary [masses M(B) = 0.2413 ± 0.0030 solar mass (M(⊙)), M(C) = 0.2127 ± 0.0026 M(⊙); radii R(B) = 0.2543 ± 0.0014 solar radius (R(⊙)), R(C) = 0.2318 ± 0.0013 R(⊙); orbital period P(1) = 1.76713 ± 0.00019 days] on an eccentric orbit about a third star (mass M(A) = 1.347 ± 0.032 M(⊙); radius R(A) = 2.0254 ± 0.0098 R(⊙); period of orbit around the low-mass binary P(2) = 33.9214 ± 0.0013 days; eccentricity of that orbit e(2) = 0.3043 ± 0.0024). The low-mass pair probe the poorly sampled fully convective stellar domain offering a crucial benchmark for theoretical stellar models.     

Nitrogen excretion in cockroaches: uric Acid is not a major product

Thin-layer chromatographic and enzymatic spectrophotometric analyses have failed to detect uric acid in fecal extracts from American cockroaches on specified diets. Uric acid appears in the excreta when it is a dietary constituent, although most of it is apparently absorbed and stored internally. Surprisingly, ammonia is a major excretory product.     

Effects of migratory geese on nitrogen availability and primary productivity in subarctic barley fields

 Migratory geese affect agricultural production by removing biomass and by depositing fecal nutrients. This study used ¹⁵N as a tracer to examine the quantitative effects of goose fecal N contributions on agricultural production. Barley (Hordeum vulgare cv. Datal) was grown for the production of ¹⁵N-labeled grain and straw. Two Canada geese (Branta canadensis Taverners) were fed the grain after harvest to obtain ¹⁵N-labeled and unlabeled feces. Net N mineralization and micro-plot studies both indicated that in comparison to barley grain and straw, goose feces provided the greatest amount of available N to the soil and to the subsequent crop, and consequently higher barley yields (59% and 62% increase, respectively). However, C mineralization was greater from grain, with 56% evolved compared to 49% and 26% for feces and straw, respectively. Goose feces also provided the greatest addition of N for the barley plants, with fertilizer N recovery efficiency (FNRE) of 16%, compared to FNRE of 10% from the grain amendment, and 1.2% from the straw amendment. The amount of N available in fecal material from leftover grain consumed by grazing geese is small in comparison to total crop needs, but is a potential source of mineral N during the critical early growth of crops grown in cold, high-latitude soils. Received: 16 May 1999