Partial purification and comparison of precipitation techniques of proteolytic enzymes from trout (Salmo gairdnerii) heads

Proteolytic enzymes have been detected and partially purified from trout (Salmo gairdnerii) heads, which were preserved at −20 °C. Proteolytic enzymes, either in crude extract or in partial purified samples, were stable for 15 days with an optimum temperature of 55 °C. Proteolytic activity was very high in either alkaline or acidic pH regions. A particular ratio of cold acetone to crude extract (1.25:1) was found to be best for the partial purification of proteases, with a 99% recovery, compared with the partial purifications achieved using different cold acetone ratios or ammonium sulphate. This recovery was also confirmed via measurement of the particles (particle size analyser) contained either in crude extract or in the precipitated samples. The existence of mainly Zn–serine and possibly some Zn-acidic proteases was observed.     

Cycle bases of graphs and sampled manifolds

Point samples of a surface in are the dominant output of a multitude of 3D scanning devices. The usefulness of these devices rests on being able to extract properties of the surface from the sample. We show that, under certain sampling conditions, the minimum cycle basis of a nearest neighbor graph of the sample encodes topological information about the surface and yields bases for the trivial and non-trivial loops of the surface. We validate our results by experiments.     

Browsing shortcuts as a means to improve information seeking of blind people in the WWW

This paper presents a “Semantic Web application framework” which allows different applications to be designed and developed for improving the accessibility of the World Wide Web (WWW). The framework promotes the idea of creating a community of people federating into groups (ontology creators, annotators, user-agent developers, end-users) each playing a specific role, without the coordination of any central authority. The use of a specialised voice web browser for blind people, called SeEBrowser, is presented and discussed as an example of an accessibility tool developed based on the framework. SeEBrowser utilises annotations of web pages and provides browsing shortcuts. Browsing shortcuts are mechanisms, which facilitate blind people in moving efficiently through various elements of a web page (e.g. functional elements such as forms, navigational aids etc.) during the information-seeking process, hence operating effectively as a vital counterbalance to low accessibility. Finally, an experimental user study is presented and discussed which evaluates SeEBrowser with and without the use of browsing shortcuts.     

Electron Effective Mass and <Emphasis Type="Italic">g</Emphasis> Factor in Wide HgTe Quantum Wells

The magnetic-field (0 T < B < 9 T) dependence of the longitudinal and Hall resistances at fixed temperatures (2 K < T < 50 K) for the HgCdTe/HgTe/HgCdTe system with a HgTe quantum well 20.3 nm in width are measured. The activation analysis of the magnetoresistance curves is used as a tool for identifying the mobility gaps between neighboring Landau levels. The activation-energy values obtained from the temperature dependences of the longitudinal resistance in the plateau regions of the quantum Hall effect with the filling factors ν = 1, 2, 3 make it possible to estimate the effective mass and the g factor of electrons in the system under study. Indications concerning the possibility of large values of the g factor (? 80) are obtained.     

Effect of way of cooking on content of essential polyunsaturated fatty acids in muscle tissue of humpback salmon (Oncorhynchus gorbuscha)

Contents of fatty acids in filets of unfrozen (control), boiled, fried, roasted and boiled in a small amount of water humpback salmon, collected from a wholesale market in Krasnoyarsk city (Siberia, Russia) were analyzed. Special attention was paid to essential polyunsaturated fatty acids of ω3 family: eicosapentaenoic, 20:5ω3 (EPA) and docosahexaenoic, 22:6ω3 (DHA). Heat treatment in general did not decrease content of EPA and DHA in humpback, except a modest reduction during frying. Cooked humpback appeared to be the valuable source of essential ω3 PUFAs, namely EPA and DHA. It was hypothesized that the absence of significant reduction of PUFAs’ contents in red flesh of fishes of Salmonidae family during heat treatment may be due to a high level of natural antioxidants which formed in the course of evolution as adaptation to their ecological niche.     

The interplay of online shopping motivations and experiential factors on personalized e-commerce: A complexity theory approach

The present study aims to examine purchase behavior in personalized online shopping by employing complexity theory, based on customers’ online shopping experience and online shopping motivations. To address its objectives, a conceptual model is proposed along with research propositions. The research propositions are validated through a survey on 401 customers’ experience with online shopping, by using the data analysis tool fsQCA (fuzzy-set Qualitative Comparative Analysis). The results, indicate nine configurations of online shopping experience and online shopping motivations that lead to high purchase intentions. This study takes a step further the literature of online shopping and the theoretical ground of how customers’ online shopping experience combines with their online shopping motivations in order to predict and explain increased intention to purchase. The findings offer implications for both researchers and online retailers, regarding the development of new theories in personalized e-commerce and the provision of personalized services.