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Individual plant and population biomass of dominant shrubs in Patagonian grazed fields
Oatibia,Gastón R; Aguiar,Martín R; Cipriotti,Pablo A; Troiano,Fernando;
Ecolog?-a austral , 2010,
Abstract: estimating aboveground biomass of vegetation is essential for population, community and ecosystem studies. in systems dominated or co-dominated by woody species, biomass estimation is difficult, and rapid and non-destructive methods are needed. in this study, we describe biomass distribution in different components (i.e., wood, leaves) and how this changes with shrub size for the three dominant species of shrubs in the occidental district of the patagonian steppe. we also describe the population size structure of the three species in grazed fields and estimate their contribution to total abundance and biomass through a non-destructive method. we developed allometric equations to estimate aboveground biomass components of individual shrubs from structural descriptors (i.e., diameter and height of the crown), sampling individual plants of different sizes. the variable that best predicted biomass of the three species was the sum of the height and the average diameter of the crown (calculated with the largest diameter and its perpendicular). allometric models for each species explained more than 83% of the variability of individual aboveground biomass. at the individual level, species had different proportions of wood, leaves and specific wood weight. increasing shrub size was accompanied by changes in the proportion of leaves to wood, and in some cases, the percentage of dead crown. at the population level, the three species differed in size distribution in moderately grazed fields. development of allometric models from a population perspective is important to study demographic processes that drive community and ecosystem responses to environmental and land-use changes.
Health Benefits of Methylxanthines in Cacao and Chocolate
Rafael Franco,Ainhoa Oatibia-Astibia,Eva Martínez-Pinilla
Nutrients , 2013, DOI: 10.3390/nu5104159
Abstract: One may wonder why methylxanthines are so abundant in beverages used by humans for centuries, or in cola-drinks that have been heavily consumed since their appearance. It is likely that humans have stuck to any brew containing compounds with psychoactive properties, resulting in a better daily life, i.e., more efficient thinking, exploring, hunting, etc., however, without the serious side effects of drugs of abuse. The physiological effects of methylxanthines have been known for a long time and they are mainly mediated by the so-called adenosine receptors. Caffeine and theobromine are the most abundant methylxanthines in cacao and their physiological effects are notable. Their health-promoting benefits are so remarkable that chocolate is explored as a functional food. The consequences of adenosine receptor blockade by natural compounds present in cacao/chocolate are here reviewed. Palatability and health benefits of methylxanthines, in general, and theobromine, in particular, have further contributed to sustain one of the most innocuous and pleasant habits: chocolate consumption.
Stress Loops Effect in Ductile Failure of Mild Steel  [PDF]
O.O. Oluwole
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2009, DOI: 10.4236/jmmce.2009.84026
Abstract: A simulation study of effect of stress on mild steel microstructure has revealed stress loops at areas of stress application which are believed to be the root cause of the ductile failure morphology (cup and cone) in ductile alloys under plane strain conditions. The areas of concentration of these stress loops were observed to be that of subsequent instability (or necking) observed in mild steel and other materials of low friction (flow) stress. Shear stress loops with angular bearing of 450 to the tensile axis were observed to instigate both the failure site and shear morphology in these materials. In plane stress conditions, shear was seen to be that of a wave shape running obliquely to area of stress application resulting in oblique necking observed in thin mild steel sheets.
Boundary Value Problem for an Operator-Differential Riccati Equation in the Hilbert Space on the Interval  [PDF]
O. O. Pokutnyi
Advances in Pure Mathematics (APM) , 2015, DOI: 10.4236/apm.2015.514081
Abstract: The paper is devoted to obtaining the necessary and sufficient conditions of the solvability of weakly perturbed boundary-value problems for the nonlinear operator-differential Riccati equation in the Hilbert space on the interval and whole line with parameter ?. We find the solution of the given boundary value problem which for ε = 0 turns in one of the solutions of generating boundary value problem. Solution of the generating problem is constructed with the using generalized operator in analytical form. Iterative process for finding of solutions of weakly nonlinear equation with quadratic error is constructed.
Vertex-transitive maps on a torus
O. Such
ACTA MATHEMATICA UNIVERSITATIS COMENIANAE , 2011,
Abstract: We examine FVT (free, vertex transitive) actions of wallpaper groups on semiregular tilings. By taking quotients by lattices we then obtain various families of FVT maps on a torus, and describe the presentations of groups acting on the torus. Altogether there are 29 families, 5 arising from the orientation preserving wallpaper groups and 2 from each of the remaining wallpaper groups. We prove that all vertex-transitive maps on torus admit an FVT map structure.
Vertex-transitive maps on a torus
O. Such
ACTA MATHEMATICA UNIVERSITATIS COMENIANAE , 2011,
Abstract: We examine FVT (free, vertex transitive) actions of wallpaper groups on semiregular tilings. By taking quotients by lattices we then obtain various families of FVT maps on a torus, and describe the presentations of groups acting on the torus. Altogether there are 29 families, 5 arising from the orientation preserving wallpaper groups and 2 from each of the remaining wallpaper groups. We prove that all vertex-transitive maps on torus admit an FVT map structure.
Definition of secret reasons of errors, appeared during aviation operators’ professional activity Определение скрытых причин происхождения ошибок, возникающих в профессиональной деятельности авиационных операторов ВИЗНАЧЕННЯ ПРИХОВАНИХ ПРИЧИН ПОХОДЖЕННЯ ПОМИЛОК, ЩО ВИНИКАЮТЬ У ПРОФЕС ЙН Й Д ЯЛЬНОСТ
O.?. Луппо,О.М. Ал?кс??в
Proceedings of National Aviation University , 2005,
Abstract: Development of discover secret reasons of error actions of aviation operators allows to define reasons of secret factors of error action in time and will give opportunity to develop more effective prevention measures in order to prevent mistake actions in time. Разработана система выявления скрытых причин ошибочных действий авиационных операторов, позволяющая своевременно определять причины и механизмы возникновения скрытых факторов, которые приводят к ошибочным действиям, и осуществлять более действенные профилактические мероприятия по их своевременному предотвращению. Розроблено систему виявлення прихованих причин помилкових д й ав ац йних оператор в, що дозволя сво часно визначати причини механ зми виникнення прихованих чинник в, як призводять до помилкових д й, та зд йснювати б льш д в проф лактичн заходи щодо х сво часного запоб гання.
НТЕГРАЦ Я ЗАСОБ В Д АГНОСТИКИ, ПРОГНОЗУВАННЯ КЕРУВАННЯ Р ВНЕМ БЕЗПЕКИ ПОЛЬОТ В Integration of diagnosis, prognosis and management level of safety Интеграция средств диагностики, прогнозирования и управления уровнем безопасности полетов
В.П. Харченко,O.?. Луппо,О.М. Ал?кс??в
Proceedings of National Aviation University , 2007,
Abstract: Розглянуто один з шлях в п двищення контролю за р внем безпеки польот в нтеграц я вс х засоб в форм у комплексних автоматизованих системах. Запропоновано виб р кращого вар анта засобу керування р внем безпеки польот в за допомогою комплексного автоматизованого застосування математичних моделей, методолог чних п дход в до виконання початкових етап в моделювання, концептуального проектування, формал зац алгоритм зац моделей. One of ways rise and control after a level of safety flights is integration of all facilities and forms in the complex automated systems. Acceptance of decision about the choice of the best forms management of mean safety flights level in such terms is erected to satisfaction a number of indexes, and in spite of their possible contradiction is a problem which it is possible to decide by means the complex automated use application of mathematical models, methodological approaches to implementation initial stages of design, conceptual design, formalization and algoritmizationi of models and bases management mean of safety flights level. Рассмотрен один из путей повышения и контроля за уровнем безопасности полетов - интеграция всех средств и форм в комплексных автоматизированных системах. Предлагается выбор лучшего варианта средства управления уровнем безопасности полетов с помощью комплексного автоматизированного применения математических моделей, методологических логических подходов к выполнению начальных этапов моделирования, концептуального проектирования, формализации и алгоритмизации моделей.
НОВ П ДХОДИ ДО КЛАСИФ КАЦ ПРИЧИН АВ АЦ ЙНИХ ПОД Й ТА НЦИДЕНТ В ЯК ЕФЕКТИВНИЙ ЗАС Б П ДВИЩЕННЯ БЕЗПЕКИ ПОЛЬОТ В New approaches to the classification of causes of aviation accidents and incidents as an effective means of improving safety Новые подходы к классификации причин авиационных происшестви
O.?. Луппо,О.М. Ал?кс??в
Proceedings of National Aviation University , 2007,
Abstract: Розглянуто класиф кац ю ав ац йних под й та нцидент в, що да змогу оц нити питому частку кожно структури в зниженн безпеки польот . Виявлено головн причини та частоту повторюваност ав ац йних под й та нцидент в. Оц нено ефективн сть ран ше розроблених проф лактичних заход в щодо попередження однотипних ав ац йних под й та нцидент в у майбутньому. Classification of accidents and incidents makes principle of hieratic collateral subordination, which determines separate classification of direct and main reasons that enables to estimate weight destiny of every structure in the decline of safety flight and expose most bottleneck in the aviation system. Exposure of main reasons and frequency of their repetition, for a concrete period, allows to define the role of each components in the decline of safety of flights and estimate efficiency of the before developed prophylactic measures from warning of the same type aviation events and incidents in a future. Рассмотрены классификация авиационных происшествий и инцидентов, что позволяет оценить удельную долю каждой структуры в снижении безопасности полете. Выявлены основные причины и частоту повторяемости авиационных происшествий и инцидентов. Оценена эффективность ранее разработанных профилактических мероприятий по предупреждению однотипных авиационных происшествий и инцидентов в будущем.
THE PLACE AND THE ROLE OF THE INFORMATION AND COMMUNICATION TECHNOLOGIES IN THE SYSTEM OF EDUCATION IN EUROPEAN UNION COUNTRIES М СЦЕ ТА РОЛЬ НФОРМАЦ ЙНИХ ТА КОМУН КАЦ ЙНИХ ТЕХНОЛОГ Й В СИСТЕМ ОСВ ТИ КРА Н ВРОПЕЙСЬКОГО СОЮЗУ
О.В. Oвчарук
Information Technologies and Learning Tools , 2010,
Abstract: The article deals with the analysis of the problems of ICT application in education sphere in European Union. Particularly the article is about the pupils and teachers access to electronic means and Internet, as well as about ICT place in the school curricula. Стаття присвячена анал зу проблем нформатизац осв ти в кра нах вропейського Союзу, зокрема, доступу учн в та педагог в до електронних засоб в навчання, мереж нтернет. Подано нформац ю щодо м сця КТ в зм ст осв ти загальноосв тн х навчальних заклад в.
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