Debate continues about the nature of the Cretaceous-Paleogene (K-Pg) mass extinction event. An abrupt crisis triggered by a bolide impact contrasts with ideas of a more gradual extinction involving flood volcanism or climatic changes. Evidence from high latitudes has also been used to suggest that the severity of the extinction decreased from low latitudes towards the poles. Here we present a r...

This paper describes how to compute equations of plane models of minimal Du Val double planes of general type with pg = q = 1 and K = 2, . . . , 8. A double plane with K = 8 having bicanonical map not composed with the associated involution is also constructed. The computations are done using the algebra system Magma. 2000 Mathematics Classification: 14J29, 14Q05.

The potential for antibiotic residues in calves from consuming milk containing penicillin G or amoxicillin was investigated. Six calves were fed milk replacer, 6% body weight twice daily, containing 0.293, 2.92, or 5.85 microg of penicillin/ml (ppm) G or 0.25, 1.0, or 2.0 microg of amoxicillin/ml for three consecutive feedings. Urine and blood samples were collected after each feeding. Serum an...

概 要 少な くとも約5年 間に わた り持続 してい る慢性 心房性 頻拍症の36才 男子例 について報告 した. 心電 図上第I誘 導 のP波 は陰性,心 房拍動 数は1分 間120~150の こ とが多 く比較的緩徐 であ り,か つ,多 くの場 合 にWenckebach周 期あ るいは2:1の 房室 ブ ロック を伴 なつ た.PP間 隔,お よび房 室間 伝導 は 自然 にも変 動す る他に,情 動,体 動,体 位変換 などに よ り容易 に変 化 し,そ の 範囲は1分 間 約190の1:1房 室伝導 に まで及 び,他 方,Aschner試 験 に よ りPP間 隔は1秒 以上 に まで延長 した.digitalis薬, procaine amide.,迷 走神経 反射 な どに よ り,異所性調律 の消失は きたさなかつた. 本頻 拍は発作性 頻 拍症 とは種 々の...

A major glutamine tRNA from rat liver was purified. Post-labeling techniques showed its nucleotide sequence to be: pG-G-U-U-C-C-A-U-m(1)G-G-U-G-psi-A-A-D-Gm-G-D-D-A-G-C-A-C-U-C-U-G-G-A-Cm-U-C-U-G-A-A-psi-C-C-A-G-C-G-A-U-m(5)C-m(5)C-G-A-G-psi-psi-C-A-m(1)A-A-U-C-U-C-G-G-U-G-G-A-A-C-C-U-C-C-A(OH).Images

Stephen Stich Rutgers University Abstract: While we are enthusiastic about a Darwinian approach to culture, we argue that the overview presented in the target article does not sufficiently emphasize the crucial explanatory role that psychology plays in the study of culture. We use a number of examples to illustrate the variety of ways that appeal to psychological factors can help explain cultu...

Water anomalies still defy explanation. In the supercooled liquid, many quantities, for example heat capacity and isothermal compressibility κT, show a large increase. The question arises if these quantities diverge, or if they go through a maximum. The answer is key to our understanding of water anomalies. However, it has remained elusive in experiments because crystallization always occurred ...

Minimal surfaces of general type with pg = q (i.e with χ(O) = 1, the minimal possible value) have attracted the interest of many authors, but we are very far from a complete classification of them. Gieseker theorem ensures that there are only a finite number of families, but recent results show that the number of this families is huge, at least for the case pg = q = 0 (cf. [PK] for many example...