A chymotryps in l ike endopeptidase has been purif ied by ion-exchange chromatography, affinity chromatography, and gel f i l tration. The enzyme preparation is homogeneous in the u l t r a centrifuge and disc electrophoresis. The enzyme is proved to be free f rom any other proteolytic activities. The molecular weight of the proteinase as determined w i t h several techniques (ultracentrifugati...

Recently, there has been a great deal of interest in the research literature regarding how environmental practices (EPs) can improve firm performance. According to Rondinelli and Vastag (1995), firms may have been reacting to an increasingly difficult regulatory environment or responding to market pressure. Either way, the responses of firms to environmental pressures has led to practices that ...

The present work shows the results obtained from experimental investigations of the augmentation of turbulent flow heat transfer in a horizontal tube by means of mesh inserts with air as the working fluid. Sixteen types of mesh inserts with screen diameters of 22mm, 18mm, 14mm and 10mm for varying distance between the screens of 50mm, 100mm, 150mm and 200mm in the porosity range of 99.73 to 99....

Mixture-of-experts (MoE) models are a powerful paradigm for modeling of data arising from complex data generating processes (DGPs). In this article, we demonstrate how different MoE models can be constructed to approximate the underlying DGPs of arbitrary types of data. Due to the probabilistic nature of MoE models, we propose the maximum quasilikelihood (MQL) estimator as a method for estimati...

Undisputable fact is that 14000 people in Sub-Saharan Africa are being infected daily with HIV and 11000 are dying every day due to HIV/AIDS related illnesses. In this region more than 60% of the people live below UN poverty line of US$ 1 per day. Some studies have shown that poverty and HIV infection are in correlation, but none has shown whether HIV/AIDS in Sub-Saharan Africa is an outcome of...

A time-of-flight mass spectrometric study of the prompt and metastable decomposition of ions produced by “‘Cf fission fragment bombardment is presented. Results for a series of polypeptides with molecular weights between 1000 and 14000 u are given. Comparisons are made between the amount of fragmentation observed in ions desorbed from bulk (electrosprayed) polypeptide samples and the amount of ...

Abstract The topic of sustainability, and in particular the sustainability practices companies, is especially relevant nowadays. introduction such very important for Eastern European countries, including Bulgaria. This study part a large-scale university project (UNWE, Sofia) that focuses precisely on international business. aim to find out if Bulgarian companies are familiar with sustainable w...

This article goes through the implementation of a mass sensor based on mode localization with two coupled quartz resonators. The resonators are digitally by mean field programmable gate array that also allows to compensate their fabrication defects. As both this compensation and coupling digital, resonances can be close in frequency, especially as Q factor these is much higher than conventional...