Sporeless mutants of Bacillus thuringiensis. II. mutants derived from var. thuringiensis and var. sotto.

Three sporeless mutants of Bacillus thuringiensis, 2 derived from var. thuringiensis and 1 from var. sotto were selected after mutagenic treatment. They were completely lacking in ability to form spores, yet maintained intact insecticidal activity.     

The effects of age and nutritional state on m.e.p.p. amplitude

Summary A quantitative restriction of food intake for 7 days reduced the amplitude of spontaneous miniature endplate potentials by about 1/3 in rats aged 30 days but not in rats aged 110 days.I would like to thank Dr D. V. Roberts for encouragement and advice and the Medical Research Council and the Muscular Dystrophy Group of Great Britain for financial support.     

Toxic substances produced byFusarium. III. Production and screening of phytotoxic substances ofF. oxysporum f. sp.carthami responsible for the wilt disease of safflowerCarthamus tinctorius Linn.

Summary Fusarium oxysporum f. sp.carthami, a causative agent for the wilt disease of safflower (Carthamus tinctorius Linn.), has been shown to produce diacetoxyscirpenol, T-2 toxin, fusaric acid and lycomarasmin in artificial media. These substances produced disease syndromes, similar to those seen after the natural infection, when administered in healthy plants. Diacetoxyscirpenol and T-2 toxin have been detected in diseased safflower plants after inoculating with the wilt pathogen. This study is the first demonstration of vivotoxicity of diacetoxyscirpenol.     

Biochemical compartmentation of fish tissues. II. Nonspecific phosphomonoesterases in brain.

The specific activities of acid and alkaline phosphatases in different regions of the brain of 9 nutritionally important fishes were worked out. The region consisting of pituitary, hypothalamus and thalamus showed the highest acid and alkaline phosphatase activities. Least activities of both the enzymes were found in the cerebellum and medulla oblongata. The piscivorous fishes contain the highest acid and alkaline phosphatase activity followed by cat fishes and major carps. The distributional pattern of these 2 enzymes in 4 regions of the brain of 9 fishes is the same.     

Ultrastructure of cell-mediated immunity. I. Comparison between E and EA rosettes.

The ultrastructural comparison between E and EA rosettes showed that, in the former, the rosetting lymphocytes are mostly round in shape and their interaction with sheep erythrocytes only consists of limited areas of membrane contact, in the latter, rosetting lymphocytes are mostly in the shape of uropods and surrounding ox red cells show pseudopods protruding towards the lymphocyte and coming into contact with it.     

The portraiture of the honourable Robert Boyle,F.R.S.

“To whom is the Consecration of Medal, Stature or even Pyramid more jusly due, than to … the late Illustraious Boyle? … for the happy Improvement of Otto Guericks Magdeburg Exhausterm and for his Profound and Noble Researches into all the abstruser Parts and Recesses of the most useful Philosophy … I have named the Illustrious Boyle, and fix his Trophy here.”

John Evelyn, Numismata, 1697.

     

Aging of the erythrocyte. III. Cation content

Summary Studies on the main cation content of density-separated bovine erythrocytes showed a progressive decrease in the levels of K⁺ and Mg²⁺ with increasing cell density (and age) accompanied by an increase in the level of Na⁺. The magnitude of net cation loss corresponded to that of red cell volume decrease, but could not account for the total increase in the microviscosity of the erythrocyte interior.     

Spin label studies of ATP phosphoribosyltransferase of E. coli.

Covalently bound bromoacetamide nitroxides have been used to detect the conformational changes and enzyme association induced by its feedback inhibitor, histidine.     

美国登月火箭项目进展

研究美国登月火箭的项目管理有助于我国探月工程的规划。2004年美国公布重返月球计划。为实现这一目标，美国国家航空航天局决定以航天飞机推进系统为基础研制新型运载火箭。新火箭于2006年被命名为“战神”，包括“战神”-1乘员运载火箭和“战神”-5货物运载火箭两种型号。目前，“战神”-1火箭已完成系统需求评审，进入设计评审阶段。火箭第一级、上面级、上面级发动机以及电子设备的研制合同都已于2007年授出。预计2009年5月进行首次试验飞行，2015年3月进行首次载人飞行。而“战神”-5火箭还处于早期研究阶段。由于预算调整和航天项目的复杂性，“战神”火箭的研制已经有所拖延。虽然大型航天集团和国家航空航天局努力争取更多预算，但“战神”火箭未来的研制不排除进一步拖延的可能。     

Aging of the erythrocyte. II. Activities of peroxide-detoxifying enzymes

Summary The activity of glutathione peroxidase decreases and that of catalase does not change during erythrocyte aging, as judged from a comparison of bovine red cell fractions separated by density.We are indebted to Prof. W. Leyko for many stimulating discussions.     

Use ofEscherichia coli A.T.C.C. 9637 for the asymmetric hydrolysis of amino acid derivatives

Riassunto L'azione delle acilasi presenti nelle cellule diE. coli A.T.C.C. 9637 è stata studiata utilizzando diversi substrati. Si è così trovato che alcuni cloroacetil e fenilacetil amino acidi subiscono un'idrolisi asimmetrica.