Some limitations of using super-pressure balloons for probing the middle atmosphere of Venus are discussed. In particular, the accuracy of derived vertical wind velocities obtained from the VEGA flights is questioned. Concerns about using baseline superpressure balloons to achieve circumnavigation of Venus are raised. Alternatives to super-pressure balloons are reconsidered. To acquire long dur...

Reliability of kinetic parameters are crucial in understanding enzyme kinetics within cellular system. The present study suggests a few cautions that need introspection for estimation of parameters like M K , Max V and I K using Lineweaver-Burk plots. The quality of 50 IC too needs a thorough reinvestigation because of its direct link with I K and M K values. Inhibition kinetics under both stea...

A reinvestigation of the relationship between the Crick-Harper-Raper (CHR) and the GIH clinical units (CU) of secretin has been undertaken in anaesthetized cats with the knowledge that for some time before 1970 the CHR standard used by The Boots Company to assay secretin had lost some specific activity. One clinical unit of GIH secretin (batch no. 17421) is 3-8 times more potent than 1 Crick-Ha...

A reinvestigation of Strychnos icaja roots has resulted in the isolation of two tertiary quasi-symmetric bisindole alkaloids named strychnogucines A (1) and B (2). Their structures were identified by means of spectroscopic data interpretation. Compound 2 was highly active in vitro and compound 1 moderately active against four strains of Plasmodium falciparum. Strychnogucine B (2) was more activ...

A series of 6alpha- and 6beta-substituted benztropines were synthesized. A marked enantioselectivity was observed for the 6beta-methoxylated benztropines, the (1R)-isomers being more potent than the corresponding (1S) compounds. The racemic 6alpha-methoxy-3-(4',4' '-difluorodiphenylmethoxy)tropane (5 g) was the most potent compound. It has been found that modifications at the 6-position of benz...

Purpose: The construction industry in Pakistan faces a turbulent environment and multiple challenges to achieve its targets. In such situations, the interest innovation grows, especially management innovation, conviction about significant role boosting organizational performance gains researchers’ interest. Accordingly, this article examines mediating of relationship between performance. Design...

This paper reworks and expands on the results of existing simulation studies, investigating the performance of various robust estimators of scale for Tukey’s three corner distributions. We focus attention on the popular biweight A-estimator, but also propose a new estimator based on the Student’s t-distribution, which attains efficiency close to that of the A-estimator. We investigate use of mo...

The crystal structure of the mineral lautite (copper arsenic sulfide), CuAsS, previously described as either centrosymmetric [Pnma; Marumo & Nowacki (1964 ▶). Schweiz. Miner. Petro. Mitt.44, 439-454] or noncentrosymmetric [Pna2(1); Craig & Stephenson (1965 ▶). Acta Cryst.19, 543-547], was reinvestigated by means of single-crystal X-ray diffraction. The centrosymmetric structural model reported ...

We have recently shown that the exclusion process causing the replacement of DNA ligases II by DNA ligase I in amphibian eggs after fertilization does not occur in the case of Xenopus laevis [Hardy, S., Aoufouchi, S., Thiebaud, P., and Prigent, C., (1991) Nucleic Acids Res. 19, 701-705]. Since this result is in contradiction with the situation reported in axolotl and Pleurodeles we decided to r...