The earliest spectroscopy of the GRB 030329 afterglow with 6-m telescope

The earliest BTA (SAO RAS 6-m telescope) spectroscopic observations of the GRB 030329 optical transient (OT) are presented, which almost coincide in time with the "first break" ($t\sim 0.5$ day after the GRB) of the OT light curve. The beginning of spectral changes are seen as early as $\sim 10-12$ hours after the GRB. So, the onset of the spectral changes for $t<1$ day indicates that the contribution from Type Ic supernova (SN) into the OT optical flux can be detected earlier. The properties of early spectra of GRB 030329/SN 2003dh can be consistent with a shock moving into a stellar wind formed from the pre-SN. Such a behavior (similar to that near the UV shock breakout in SNe) can be explained by the existence of a dense matter in the immediate surroundings of massive stellar GRB/SN progenitor). The urgency is emphasized of observation of early GRB/SN spectra for solving a question that is essential for understanding GRB physical mechanism: {\it Do all} long-duration gamma-ray bursts are caused by (or physically connected to) {\it ordinary} core-collapse supernovae? If clear association of normal/ordinary core-collapse SNe (SN Ib/c, and others SN types) and GRBs would be revealed in numbers of cases, we may have strong observational limits for gamma-ray beaming and for real energetics of the GRB sources.Comment: 4 pages, 5 figures. Proceedings of the 4th Workshop "Gamma-Ray Bursts in the Afterglow Era", Roma, 2004 October 18-22, eds. L. Piro, L. Amati, S. Covino, and B. Gendre. Il Nuovo Cimento, in pres

Cytoplasmic linker proteins promote microtubule rescue in vivo

The role of plus end–tracking proteins in regulating microtubule (MT) dynamics was investigated by expressing a dominant negative mutant that removed endogenous cytoplasmic linker proteins (CLIPs) from MT plus ends. In control CHO cells, MTs exhibited asymmetric behavior: MTs persistently grew toward the plasma membrane and displayed frequent fluctuations of length near the cell periphery. In the absence of CLIPs, the microtubule rescue frequency was reduced by sevenfold. MT behavior became symmetrical, consisting of persistent growth and persistent shortening. Removal of CLIPs also caused loss of p150Glued but not CLIP-associating protein (CLASP2) or EB1. This result raised the possibility that the change in dynamics was a result of the loss of either CLIPs or p150Glued. To distinguish between these possibilities, we performed rescue experiments. Normal MT dynamics were restored by expression of the CLIP-170 head domain, but p150Glued was not recruited back to MT plus ends. Expression of p150Glued head domain only partially restored MT dynamics. We conclude that the CLIP head domain is sufficient to alter MT dynamics either by itself serving as a rescue factor or indirectly by recruiting a rescue factor. By promoting a high rescue frequency, CLIPs provide a mechanism by which MT plus ends may be concentrated near the cell margin

PROBLEMS OF NUTRIENT ADDITIVES IN FOOD PRODUCTS

This article presents the importance of nutrient additives, aspects of their application and safety control, international codification of nutrient additives, description of dangerous nutrient additives.В настоящей статье приведены свойства и назначение пищевых добавок, причины и особенности их применения, контроль безопасности, международная классификация пищевых добавок, описание некоторых опасных свойств пищевых ингредиентов

Событийный PR в системе интегрированных коммуникаций

The article is devoted to the definition of event PR and its ways of realization. It considers main PR and market specialists’ approaches to the definition of the term «event PR». The author explores characteristic features of event PR campaigns, and their place among other integrated PR communications. The goal of this analytic article is to study advantages of event PR in promotion of brand, trademark and company as a whole. PR-events peculiarities, forms and requirements are evaluated within the study as well as high level of event PR effectiveness for goods and services promotion.Статья посвящена изучению возможностей событийного PR, способам его реализации. Рассматриваются основные подходы маркетологов и специалистов по связям с общественностью к интерпретации научной категории «событийный PR». Авторы изучают характерные признаки событийных мероприятий, а также их место среди других интегрированных PR коммуникаций. Целью исследования является изучение преимуществ событийного PR для продвижения бренда, торговой марки и организации в целом. Определяются особенности PR-мероприятий, а также их формы и требования, необходимые для достижения необходимого результата. Доказывается высокий уровень эффективности событийного PR для продвижения товара или услуг

Academic physical education system: questionnaire survey to rate student satisfaction

Objective of the study was to analyze the student satisfaction with the academic physical education servic

Emergence of Anti-Cancer Drug Resistance: Exploring the Importance of the Microenvironmental Niche via a Spatial Model

Practically, all chemotherapeutic agents lead to drug resistance. Clinically, it is a challenge to determine whether resistance arises prior to, or as a result of, cancer therapy. Further, a number of different intracellular and microenvironmental factors have been correlated with the emergence of drug resistance. With the goal of better understanding drug resistance and its connection with the tumor microenvironment, we have developed a hybrid discrete-continuous mathematical model. In this model, cancer cells described through a particle-spring approach respond to dynamically changing oxygen and DNA damaging drug concentrations described through partial differential equations. We thoroughly explored the behavior of our self-calibrated model under the following common conditions: a fixed layout of the vasculature, an identical initial configuration of cancer cells, the same mechanism of drug action, and one mechanism of cellular response to the drug. We considered one set of simulations in which drug resistance existed prior to the start of treatment, and another set in which drug resistance is acquired in response to treatment. This allows us to compare how both kinds of resistance influence the spatial and temporal dynamics of the developing tumor, and its clonal diversity. We show that both pre-existing and acquired resistance can give rise to three biologically distinct parameter regimes: successful tumor eradication, reduced effectiveness of drug during the course of treatment (resistance), and complete treatment failure