A new model of glucocorticoid-induced metanephric maldevelopment

Summary A new experimental model of glucocortocoid-induced tubular cyst formation has been developed in metanephric organ culture. The addition of cortisol (1.4×10^–5 M) to chemically defined serum-free culture medium produces cystic changes during in vitro nephrogenesis. The model isolates the role of glucocorticoids in experimental cyst formation.Acknowledgment. This work has been supported by Basil O'Connor Starter Research Grant No.5-349 from the March of Dimes Birth Defects Foundation.     

低维特征空间中基于旋转图像的三维环境模型配准方法

近年来,异类机器人之间(如飞行机器人和地面机器人)的协作成为机器人学研究发展的一个新的领域.异类机器人协作的难点之一是协作环境建模,而由于所获得的环境模型具有不同的观测视角和尺度,其环境建模中的模型配准是一个难点和关键.目前,能够适用于大视角差、大尺度差场景配准的方法并不多,基于旋转图像的配准方法被认为是一种可行方案,但其中存在的计算负担大和在野外环境中的鲁棒性差使得其也很难在实际系统中应用.基于此,面向三维点云环境模型,以旋转图像为基础,提出了一种新的基于低维特征空间的模型配准方法.首先,通过引入模型曲率、旋转图像熵值和激光反射强度3个特征构建了一个三维特征空间,得到候选对应点集合.然后,在候选对应点集合中利用旋转图像的方法查找正确的对应关系,实现模型配准.由于低维特征空间的引入,基于旋转图像特征的对应点搜索区域大大减小,因此算法计算效率得到了极大改善.同时由于引入的新特征与场景旋转图像特征的互补性,算法的鲁棒性和精确性也得到了提升.这些性能改进最后通过实验得到了验证.     

A heuristic model of creativity

Zusammenfassung Im Rahmen eines heuristischen Modells und unter dem Einfluss der psychoanaleptischen Drogc Psilocybin wird die regulierend-complementierende geistige Tätigkeit untersucht. Gesunde, junge Volontäre vermögen nach oraler Verabreichung von 10–12 mg Psilocybin gedruckte Texte zu lesen, obgleich der obere Teil jeder Zeile bis zu 74% unsichtbar ist.     

A new synthesis of dehydromunduserone

Zusammenfassung Eine einfache Synthese von Dehydromunduseron aus 7,2,4,5-Tetramethoxy-isoflavon wird beschrieben.     

Evaluation of oral vaccination against mouse-typhoid in a new animal model

Summary In a simple, new animal model the spread of mouse-typhoid within a mouse-colony was studied and oral vaccination against this disease was evaluated. Live vaccine was superior to inactivated vaccine.     

A new quinoline-carbamate aphicide

Summary We found that it was nearly impossible to apply the quinoline-carbamate aphicide per os by means of synthetic diets, owing to its high feeding-deterrent-effect. After application via the roots of the host plant, this systemic compound is deposited on the leaf surface. The results suggest that the toxic effect is not the result of the oral uptake of phloem sap, but of the tarsal contact with the toxicant. Sensitivity of aphids to this compound and LD₅₀-values were determined after topical applicationsWe are grateful to the Deutsche Forschungsgemeinschaft for offering a grant.Israel Institute for Biological Research, Ness-Ziona, visiting professor (Oct. 1974–Sep. 1975), Institut für Angewandte Zoologie der Universität Bonn (BRD).     

A new guanidine alkaloid

Zusammenfassung Ein neues Alkaloid, Pterogynin, wurde aus der Rinde vonPterogyne nitens Tul. (Leguminosae) isoliert und seine Struktur bestimmt. Es handelt sich um das N,N-Di(isopenten-2-yl)-guanidin.

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Part XIV ofStudies on Plants; proceding part, R. A.Corral, O. O.Orazi and I. A.Benages, Tetrahedron Letters545 (1968).     

A new air sampler

Zusammenfassung Beschreibung eines verbesserten Luftprobensammlers zur Bestimmung von Keimzahlen in der Luft.     

A rat model of neurobehavioral development

Summary The neurobehavioral evolution of the normally growing rat has been investigated by means of a series of reflex, motor and sensory tests from birth up to weaning. A sequential development of behavioral reponses has been assessed over this 21-days period, the 2nd week following birth representing an important step in the neurobehavioral maturation of the rat. This rat model may be considered as an useful reference to evaluate changes that may be induced by pharmacological and toxicological agents in the developing exposed rat.Acknowledgment. We thank Mrs D. Huot-Blais for her secretarial assistance.     

A model of enzymatic kinetics]

In this Note, we study a system of differential equations representing the kinetics of an enzymatic reaction. For a closed system, and in the domain where it has a biological significance, it is shown that: (i) there exists a unique equilibrium point, which is an asymptotically stable point; (ii) if several enzymes act on the same substrates, the equilibrium values of the substrates concentrations take their values within the range of the equilibrium values achieved with each of these enzymes, (iii) the kinetics of the reaction can be approached by a single first-order differential equation, which may be seen as a generalization of the Michaelis equation.     

A new spectrophotometric determination of nitrazepam

Riassunto È stata studiata per via spettrofotometrica la reazione cromatica tra nitrazepam e 1,2-naftochinone in dimetilformammide (DMF) in presenza di ammoniaca. È stato stabilito che in soluzione si forma un addotto molecolare dei due reagenti in rapporto molare 11. Tale reazione viene proposta come metodo di determinazione colorimetrica del nitrazepam in liquidi biologici quali sangue, saliva ed urina.     

A new partial synthesis of holaphyllamine

Résumé L'holaphyllamine peut être aisément préparée à partir du 3, 6-ditosyloxy-5-pregnan-20-one par réaction avec NaN₃.     

A new N-glucuronide metabolite of carbamazepine

Summary An N-glucuronide metabolite of carbamazepine was identified in the bile of the isolated perfused rat liver by means of permethylation, gas chromatography and mass spectrometry.This research was supported by grants from the National Institutes of Health (Nos. N01-NS-5-2328, AM-17665) and the James Whitcomb Riley Memorial Association (No. 74-15) and a grant from the Epilepsy, Foundation of America.