Evaluation of approaches to increase the effectiveness of various disinfectants against biofilm communities of different ages

Disinfectants are used as the main agents against microorganisms circulating on the surfaces of food enterprises. However, the adaptive ability of microorganisms to form biofilms complicates the process of surface cleaning and reduces the effectiveness of disinfectants. Modern disinfectants act against freely circulating microflora, but it is known that they are not always effective against biofilms. The purpose of this study was to investigate effective disinfectant compositions with bactericidal effect on binary bacterial biofilms of different ages. The article describes the effects of disinfectants based on chlorine, peracetic acid and quaternary ammonium compounds with enzymes in concentrations recommended by the manufacturer and increased several times on Salmonella 38, Brochothrix thermosphacta 2726 and Staphylococcus equorum 2736 planktonic cultures and binary biofilms. Binary biofilms of different ages (2 and 9 days old) were exposed to disinfectants with various active ingredients in combination with adjuvants, i. e. hydrogen peroxide 6% and various concentrations of isopropyl alcohol (30%). All products in concentrations recommended by the manufacturer did not have a disinfectant effect against the studied biofilm cultures. As a result of the work, it was found that the most effective disinfectants against multispecies biofilms were quaternary ammonium compounds in combination with enzymes and chlorine in combination with isopropyl alcohol (30%). The results obtained allow to expand knowledge about effective methods for controlling biofilms.Disinfectants are used as the main agents against microorganisms circulating on the surfaces of food enterprises. However, the adaptive ability of microorganisms to form biofilms complicates the process of surface cleaning and reduces the effectiveness of disinfectants. Modern disinfectants act against freely circulating microflora, but it is known that they are not always effective against biofilms. The purpose of this study was to investigate effective disinfectant compositions with bactericidal effect on binary bacterial biofilms of different ages. The article describes the effects of disinfectants based on chlorine, peracetic acid and quaternary ammonium compounds with enzymes in concentrations recommended by the manufacturer and increased several times on Salmonella 38, Brochothrix thermosphacta 2726 and Staphylococcus equorum 2736 planktonic cultures and binary biofilms. Binary biofilms of different ages (2 and 9 days old) were exposed to disinfectants with various active ingredients in combination with adjuvants, i. e. hydrogen peroxide 6% and various concentrations of isopropyl alcohol (30%). All products in concentrations recommended by the manufacturer did not have a disinfectant effect against the studied biofilm cultures. As a result of the work, it was found that the most effective disinfectants against multispecies biofilms were quaternary ammonium compounds in combination with enzymes and chlorine in combination with isopropyl alcohol (30%). The results obtained allow to expand knowledge about effective methods for controlling biofilms

Evaluating the effect of various types of disinfectants on bacterial biofilms

Biofilm formation on equipment surfaces is a potential food safety hazard, providing increased resistance and persistence of pathogens and spoilage microorganisms in food production environments. The issue of preventing the biofilm formation is extremely important, since a wide range of disinfectants does not always provide the proper effect. The article discusses the antimicrobial effectiveness of disinfectants with various active ingredients (based on active chlorine, peracetic acid and quaternary ammonium compounds (QAC) with enzymatic substances) on binary biofilms. The objects of the study were the strains of pathogenic and opportunistic microorganisms isolated from abiotic surfaces of food production environments and food products. Different effects of disinfectants on biofilms formed by bacteria have been established. Disinfectant based on peracetic acid and chlorine had the greatest effect on binary biofilms of Brochothrix thermosphacta/Salmonella spp. and Staphylococcus equorum/Salmonella spp. The greatest antimicrobial effect on biofilm of Listeria monocytogenes 12/Pseudomonas azotoformans 6 was shown by a chlorine-based disinfectant. Disinfectants based on chlorine and QAC with enzymatic substances were most effective against the binary biofilm of L. monocytogenes 12/Salmonella spp. 14. However, none of the disinfectants had absolute antimicrobial effectiveness against the studied binary biofilms. Biofilm-forming microorganisms have shown resistance to the recommended concentrations of disinfectants. Therefore, currently, it is extremely important to revise approaches to hygiene at enterprises by finding working concentrations of new antimicrobial agents and new procedure that are effective for destroying biofilms

Распознавание аэродинамических объектов по спектральным портретам с учетом конструктивных особенностей турбореактивных двигателей

In the article the device of radar-tracking recognition allowing on the basis of the analysis of a design of impellent installation to define a class (type) of observable air object is considered. Determination of the class (type) of the observed object was carried out by studying the ratios of the modulation frequencies of the spectral radar portrait. The solving rule, as well as the device block diagram are obtained, allowing to define the class and, in addition, the type of the observed air object equipped with a turbojet engine. To form a posteriori probability density, the numerical method of Monte-Carlo was used. The results of the mathematical modelling, confirming the efficiency of the proposed device, are presented. В статье рассмотрено устройство радиолокационного распознавания, позволяющее на основании анализа конструкции двигательной установки определять класс (тип) наблюдаемого воздушного объекта. Определение класса (типа) наблюдаемого объекта осуществлялось путем исследования соотношений модуляционных частот спектрального радиолокационного портрета. Получены решающее правило, а также структурная схема устройства, позволяющие определять класс и дополнительно тип наблюдаемого воздушного объекта, оснащенного турбореактивным двигателем. Для формирования апостериорной плотности вероятности использовали численный метод Монте-Карло. Представлены результаты математического моделирования, подтверждающие эффективность предложенного устройства.

УЧЕТ РАСПРЕДЕЛЕНИЯ УГЛОВ ПРОСТРАНСТВЕННОЙ ОРИЕНТАЦИИ ЛЕТАТЕЛЬНОГО АППАРАТА ПРИ АДАПТАЦИИ РАДИОЛОКАЦИОННЫХ ПОРТРЕТОВ К ИЗМЕНЯЮЩИМСЯ УСЛОВИЯМ НАБЛЮДЕНИЯ

A method for estimating and accounting for the statistical distributions of angels for the spatial orientation of an aircraft in the interest of adapting radar systems to changing observation conditions is considered. The influence of the object observation condition on the distribution parameters of the angles of its orientation is analyzed by the method of mathematical modeling. Estimates of the analyzed distribution laws were formed by two methods: the method of statistical test and the Monte-Carlo method. The advantages and disadvantages of each method are considered. The obtained estimates of current distributions of object orientation angles allow adapting radar portraits to changing observation conditions.Рассмотрен способ оценки и учета статистических распределений углов пространственной ориентации летательного аппарата в интересах адаптации радиолокационных систем к изменяющимся условиям наблюдения. Методом математического моделирования проанализировано влияние условий наблюдения объекта на параметры распределения углов его ориентации. Оценки анализируемых законов распределения формировались двумя методами: методом статистических испытаний и методом Монте-Карло. Рассмотрены достоинства и недостатки каждого из методов. Полученные оценки текущих распределений углов ориентации объекта позволяют адаптировать радиолокационные портреты к изменяющимся условиям наблюдения

ПОВЫШЕНИЕ ЭФФЕКТИВНОСТИ СИСТЕМ РАДИОЛОКАЦИОННОГО РАСПОЗНАВАНИЯ ЗА СЧЕТ АДАПТАЦИИ К ПРОСТРАНСТВЕННОЙ ОРИЕНТАЦИИ ОБЪЕКТА НАБЛЮДЕНИЯ

An important aspect of creation of effective recognition systems is the adaptation of radiolocation portraits to the corners of the spatial orientation of the observed object. The modeling complex for estimation of efficiency of the recognition system has been developed. Using mathematical modeling, it is shown that the utilization of adaptive range-finding radiolocation portraits of the object of observation on the basis of the most plausible estimates of its angles of spatial orientation increases of the efficiency of recognition. It is noted that in the conditions of limit of time for making decision about the class of an object, the methods of adaptation must be improved.Важным аспектом создания эффективных систем распознавания является адаптация радиолокационных портретов к углам пространственной ориентации наблюдаемого объекта. Для оценки эффективности системы распознавания разработан моделирующий комплекс. Методом математического моделирования показано, что использование адаптивных дальномерных радиолокационных портретов объекта наблюдения на основе максимально правдоподобных оценок его пространственной ориентации, повышает эффективность распознавания. Отмечено, что в условиях ограничения времени на принятие решения о классе объекта методы адаптации необходимо совершенствовать

ПОВЫШЕНИЕ ТОЧНОСТИ ОЦЕНИВАНИЯ ОРИЕНТАЦИИ ЛЕТАТЕЛЬНОГО АППАРАТА В ИНТЕРЕСАХ АДАПТАЦИИ РАДИОЛОКАЦИОННЫХ ПОРТРЕТОВ К УСЛОВИЯМ НАБЛЮДЕНИЯ

The article is devoted to the increasing of the spatial orientation angles estimation accuracy of the aircraft with reference to radar systems. The structural device scheme of the spatial orientation angles estimation of the radar observation object was worked out. Using the method of mathematical modeling there was examined the errors measuring spherical coordinates object influencing to its spatial orientation angles estimation. It is shown that the using of filtered rectangular coordinates meanings of the aircraft allows increasing its spatial orientation angles estimation accuracy. The advantages and disadvantages of the aircraft spatial orientation angles estimation by the proposed method are shown in the interests of radar profiles adaptation to the observation conditions.Статья посвящена повышению точности оценивания углов ориентации летательного аппарата применительно к радиолокационным системам. Разработана структурная схема устройства оценивания углов пространственной ориентации объекта радиолокационного наблюдения. Методом математического моделирования исследовано влияние ошибок измерения сферических координат объекта на оценку углов его пространственной ориентации. Показано, что использование фильтрованных значений прямоугольных координат летательного аппарата позволяет повысить точность оценивания его углов пространственной ориентации. Отмечены достоинства и недостатки предложенного подхода оценки углов пространственной ориентации летательного аппарата в интересах адаптации радиолокационных портретов к условиям наблюдения

Report on identification of keystone species and processes across regional seas. DEVOTES FP7 Project

WP6, Deliverable 6.1, DEVOTES ProjectIn managing for marine biodiversity, it is worth recognising that, whilst every species contributes to biodiversity, each contribution is not of equal importance. Some have important effects and interactions, both primary and secondary, on other components in the community and therefore by their presence or absence directly affect the biodiversity of the community as a whole. Keystone species have been defined as species that have a disproportionate effect on their environment relative to their abundance. As such, keystone species might be of particular relevance for the marine biodiversity characterisation within the assessment of Good Environmental Status (GEnS), for the Marine Strategy Framework Directive (MSFD).The DEVOTES Keystone Catalogue and associated deliverable document is a review of potential keystone species of the different European marine habitats. The catalogue has 844 individual entries, which includes 210 distinct species and 19 groups classified by major habitat in the Baltic Sea, North East Atlantic, Mediterranean, Black Sea (EU Regional Seas) and Norwegian Sea (Non-­‐EU Sea). The catalogue and the report make use/cite 164 and 204 sources respectively. The keystones in the catalogue are indicated by models, by use as indicators, by published work (e.g. on traits and interactions with other species), and by expert opinion based on understanding of systems and roles of species/groups. A total of 74 species were considered to act as keystone predators, 79 as keystone engineers, 66 as keystone habitat forming species, while a few were thought of having multiple roles in their marine ecosystems. Benthic invertebrates accounted for 50% of the reported keystone species/groups, while macroalgae contributed 17% and fish12%. Angiosperms were consistently put forward as keystone habitat forming and engineering species in all areas. A significant number of keystones were invasive alien species.Only one keystone, the bivalve Mya arenaria, was common to all four EU regional seas. The Mediterranean Sea had the largest number of potential keystones (56% of the entries) with the least in the Norwegian Sea. There were very few keystones in deep waters (Bathyal-­‐Abyssal, 200+ m), with most reported in sublittoral shallow and shelf seabeds or for pelagic species in marine waters with few in reduced/variable salinity waters. The gaps in coverage and expertise in the catalogue are analysed at the habitat and sea level, within the MSFD biodiversity component groups and in light of knowledge and outputs from ecosystem models (Ecopath with Ecosim).The understanding of keystones is discussed as to when a species may be a dominant or keystone with respect to the definition term concerning ‘disproportionate abundance’, how important are the ‘disproportionate effects’ in relation to habitat formers and engineers, what separates a key predator and key prey for mid-­‐trophic range species and how context dependency makes a species a keystone. Keystone alien invasive species are reviewed and the use of keystone species model outputs investigated. In the penultimate sections of the review the current level of protection on keystone species and the possibilities for a keystone operational metric and their use in management and in GEnS assessments for the MSFD are discussed. The final section highlights the one keystone species and its interactions not covered in the catalogue but with the greatest impact on almost all marine ecosystems, Homo sapiens

Наследственная детерминация уровня аспартатаминотрансферазы у крупного рогатого скота голштинской породы

Farm animals’ growth, development and realization of productive qualities are closely interrelated by enzymatic transformations of amino acids, proteins and other complex nitrogenous compounds. Aspartate aminotransferase (AsT) is involved in the metabolism of amino acids in the cycles of urea, tricarboxylic acids and gluconeogenesis. The level of AsT in the blood depends on many paratypical and genetic factors. The paper presents the results of a biochemical analysis of the AsT content in the blood serum of Holstein bulls aged 12-13 months, who are descendants of 4 breeding bulls. Blood sampling was carried out in animals with a live weight of 330-365 kg, bred in the conditions of a large livestock enterprise located in Western Siberia. The level of AsT in the blood serum of animals was determined by the Reitman-Frenkel colourimetric method using reagents “Transaminase AsT Novo” (manufacturer “Vector-Best” Russia). It was found that the average value of the AsT content in the groups of sons was lower than the generally accepted physiological norm and, for all descendants, was 22.44 ± 1.29 E/l. The reference interval for AsT based on the central 95% percentile with 90% confidence intervals was 12.29 (8.67...15.91) - 34.84(31.2... 38.5) E/l. The descendants of different fathers had different phenotypic variability of the indicator and differed in the level of AST. Thus, the descendants of the bull-producer Brio were characterized by a higher level compared to the sons of the bulls Malstrem and Fabio by 1.69 and 1.8 times, respectively. The revealed differences indicate the hereditary determination of the AsT level in Holstein cattle. The strength of the influence of the father’s factor was 0.18.Рост, развитие и реализация продуктивных качеств сельскохозяйственных животных тесно взаимосвязаны ферментативными превращениями аминокислот, белков и других сложных азотистых соединений. Аспартатаминотрансфераза (АсТ) участвует в метаболизме аминокислот, в циклах мочевины, трикарбоновых кислот и глюконеогенезе. Уровень АсТ в крови зависит от многих паратипических и генетических факторов. В работе представлены результаты биохимического анализа содержания АсТ в сыворотке крови бычков голштинской породы в возрасте 12–13 месяцев, являющихся потомками четырех быков-производителей. Взятие крови осуществляли у животных с живой массой 330–365 кг, разводимых в условиях крупного животноводческого предприятия, расположенного на территории Западной Сибири. Уровень АсТ в сыворотке крови животных определяли колориметрическим методом РайтманаФренкеля с использованием реактивов «Трансаминаза АсТ Ново» (производитель «Вектор-Бест» Россия). Установлено, что среднее значение содержания АсТ в группах сыновей было ниже общепринятой физиологической нормы и по всем потомкам составило 22,44 ± 1,29 Е/л. Референсный интервал для АсТ на основе центрального 95%-го процентиля с указанием 90%-х доверительных интервалов составил 12,29 (8,67–15,91) – 34,84 (31,2–38,5) Е/л. Потомки разных отцов имели разную фенотипическую изменчивость показателя и различались по уровню АсТ. Так, потомки быка-производителя Brio характеризовались более высоким её уровнем в сравнении с сыновьями быков Malstrem и Fabio – в 1,69 и 1,8 раза соответственно. Выявленные различия указывают на наследственную детерминацию уровня АсТ у крупного рогатого скота голштинской породы. Сила влияния фактора отца составила 0,18.

НЕКОТОРЫЕ БИОЛОГИЧЕСКИЕ И ХОЗЯЙСТВЕННО ПОЛЕЗНЫЕ ОСОБЕННОСТИ КРАСНОГО СКОТА АЛТАЙСКОГО КРАЯ РАЗНОГО ПРОИСХОЖДЕНИЯ

The paper characterizes 52 producers of red steppe, 49 - red Danish and 169 Angler bulls of “Barnaulskoye” enterprise in terms of erythrocyte antigen occurrence. The authors used 53 antiserums in order to determine erythrocytic antigens of 9 genetic systems. The highest frequency observed was F antigen frequency equal to 0.976-1.000. This gene was not observed in one servicing red steppe bull and four servicing Angler bulls. All red Danish bulls had F allele in a homo- or heterozygous state. The concentration of antigens A2, B2, O1, Y2, G’, Q’ (system B), C1, C2, E, R2, W, X2 (system C), H’ (system S) in the red bulls was high and equal to 0.249-0.592. The frequency of erythrocytic antigens B1, I1, P2, T1, T2, Y1, I’, D’, J2’, P1’, B” (B), R1 (C), J (J), S2, U and H” (S) was the lowest at 0-0.122. All 53 blood factors were observed in Angler cattle, but no antigens B1, P2, R1, U и B1, Y1, B” were observed in the red steppe and red Danish cattle. There are no significant differences observed in genetic similarity among three red breeds; the index of genetic similarity are 0.9211-0.9307, which indicates a high relationship among them. The highest number of ejaculates and native sperm was obtained from Angler servicing bulls, the excess over other breeds was 11.9-13.9 and 15.1-42.8%. Red steppe bulls were characterized by lowest amount of ejaculate and less bioproducts for cryopreservation were received from them. The total breeding efficiency of cows with red steppe bull sperm was 85.1%, the superiority over Danish and Angler red cattle was 7.1-11.5%.Приведена характеристика 52 производителей красной степной, 49 – красной датской и 169 быков англерской породы ОАО Племпредприятие «Барнаульское» по встречаемости эритроцитарных антигенов. В тестах использовано 53 антисыворотки, с помощью которых определяли эритроцитарные антигены 9 генетических систем. Наибольшей была частота антигена F, составив 0,976–1,000, он отсутствовал только у одного производителя красной степной породы и у четырёх – англерской породы. Все быки красной датской породы были носителями аллеля F в гомо- или гетерозиготном состоянии. Концентрация антигенов A2, B2, O1, Y2, Gʹ, Qʹ (система В), С1, С2, Е, R 2, W, X2 (система С), Hʹ (система S) у быков красных пород была высокой и составила 0,249–0,592. Наоборот, частота эритроцитарных антигенов B1, I1, P2, T1, T2, Y1, Iʹ, Dʹ, J2 ʹ, P1ʹ, Bʹʹ (B), R1 (C), J (J), S2, U и Hʹʹ (S) была наименьшей и составила 0–0,122. У англерских производителей встречались все 53 определяемых фактора крови, однако у красных степных и у красных датских не выявлены соответственно эритроцитарные антигены B 1, P2, R1, U и B1, Y1, Bʹʹ. Между животными трёх красных пород не выявлено достоверных различий по индексам генетического сходства, которые равны 0,9211–0,9307, что свидетельствует о высоком родстве между ними. От производителей англерской породы получено наивысшее количество эякулятов и нативной спермы, превышение над другими породами составило 11,9–13,9 и 15,1–42,8 %. Красные степные быки характеризовались наименьшим объёмом эякулята и от них получено меньше доз биопродукции для криоконсервации. Общая оплодотворяемость коров спермой быков красной степной породы составила 85,1 %, превосходство над красными датскими и англерскими производителями составило 7,1–11,5 абс.%