Search results: Found 18

Listing 1 - 10 of 18 << page
of 2
>>
Sort by
Fatigue Damage

Author:
ISBN: 9783038426240 9783038426257 Year: Pages: VI, 204 DOI: 10.3390/books978-3-03842-625-7 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: General and Civil Engineering
Added to DOAB on : 2017-12-22 11:24:46
License:

Loading...
Export citation

Choose an application

Abstract

There is an increasing acknowledgement in the engineering community that the response to this challenge, that is, prevention of catastrophic failure, generally requires a systems approach and necessitates engagement of a large pool of multidisciplinary expertise and the deployment of tools for systems analysis. This multidisciplinary pool includes materials science, structural analysis, manufacturing technologies, quality control and evaluation, mathematics, physics, and probability and reliability. Furthermore, from the scientific point of view, there is also an increasing acknowledgement that addressing the complex engineering problems of today requires the use of concepts and approaches that can account for size and time scaling effects. The Special Issue scope embraces interdisciplinary work aimed at understanding and deploying physics of fatigue and failure techniques, advancing experimental and theoretical failure analysis, modelling of the structural response with respect to both local and global failures, and structural design that accounts for scale and time effects in preventing engineering failures.

Keywords

Fatigue --- Design --- Crack growth --- Fracture

Mechanical Signaling in Plants: From Perception to Consequences for Growth and Morphogenesis (Thigmomorphogenesis) and Ecological Significance

Authors: --- --- ---
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889450749 Year: Pages: 93 DOI: 10.3389/978-2-88945-074-9 Language: English
Publisher: Frontiers Media SA
Subject: Botany --- Science (General)
Added to DOAB on : 2017-07-06 13:27:36
License:

Loading...
Export citation

Choose an application

Abstract

During the 1970s, renewed interest in plant mechanical signaling led to the discovery that plants subjected to mechanical stimulation develop shorter and thicker axes than undisturbed plants, a syndrome called thigmomorphogenesis. Currently, mechanosensing is being intensively studied because of its involvement in many physiological processes in plants and particularly in the control of plant morphogenesis. From an ecological point of view, the shaping of plant architecture has to be precisely organized in space to ensure light capture as well as mechanical stability. In natural environments terrestrial plants are subjected to mechanical stimulation mainly due to wind, but also due to precipitation, while aquatic and marine plants are subjected to current and wave energy. Plants acclimate to mechanically challenging environments by sensing mechanical stimulations and modifying their growth in length and diameter and their tissue properties to reduce potential for buckling or breakage. From a morphogenetic point of view, both external and internal mechanical cues play an important role in the control of cell division and meristem development likely by modulating microtubule orientation. How mechanical stimulations are being sensed by plants is an area of intense research. Different types of mechanosensors have been discovered or proposed, including ion channels gated by membrane tension (stretch activation) and plasma membrane receptor-like kinases that monitor the cell wall deformations. Electrophysiologists have measured the conductances of some stretch-activated channels and have showed that SAC of different structures can exhibit different conductances. The role of these differences in conductance has not yet been established. Once a mechanical stimulus has been perceived, it must be converted into a biological signal that can lead to variations of plant phenotype. Calcium has been shown to function as an early second messenger, tightly linked with changes in cytosolic and apoplastic pH. Transcriptional analyses of the effect of mechanical stimulation have revealed a considerable number of differentially expressed genes, some of which appear to be specific to mechanical signal transduction. These genes can thus serve as markers of mechanosensing, for example, in studies attempting to define signalling threshold, or variations of mechanosensitivity (accommodation). Quantitative biomechanical studies have lead to a model of mechanoperception which links mechanical state and plant responses, and provides an integrative tool to study the regulation of mechanosensing. This model includes parameters (sensitivity and threshold) that can be estimated experimentally. It has also been shown that plants are desensitized when exposed to multiple mechanical signals as a function of their mechanical history. Finally, mechanosensing is also involved in osmoregulation or cell expansion. The links between these different processes involving mechanical signalling need further investigation. This frontier research topic provides an overview of the different aspects of mechanical signaling in plants, spanning perception, effects on plant growth and morphogenesis, and broad ecological significance.During the 1970s, renewed interest in plant mechanical signaling led to the discovery that plants subjected to mechanical stimulation develop shorter and thicker axes than undisturbed plants, a syndrome called thigmomorphogenesis. Currently, mechanosensing is being intensively studied because of its involvement in many physiological processes in plants and particularly in the control of plant morphogenesis. From an ecological point of view, the shaping of plant architecture has to be precisely organized in space to ensure light capture as well as mechanical stability. In natural environments terrestrial plants are subjected to mechanical stimulation mainly due to wind, but also due to precipitation, while aquatic and marine plants are subjected to current and wave energy. Plants acclimate to mechanically challenging environments by sensing mechanical stimulations and modifying their growth in length and diameter and their tissue properties to reduce potential for buckling or breakage. From a morphogenetic point of view, both external and internal mechanical cues play an important role in the control of cell division and meristem development likely by modulating microtubule orientation. How mechanical stimulations are being sensed by plants is an area of intense research. Different types of mechanosensors have been discovered or proposed, including ion channels gated by membrane tension (stretch activation) and plasma membrane receptor-like kinases that monitor the cell wall deformations. Electrophysiologists have measured the conductances of some stretch-activated channels and have showed that SAC of different structures can exhibit different conductances. The role of these differences in conductance has not yet been established. Once a mechanical stimulus has been perceived, it must be converted into a biological signal that can lead to variations of plant phenotype. Calcium has been shown to function as an early second messenger, tightly linked with changes in cytosolic and apoplastic pH. Transcriptional analyses of the effect of mechanical stimulation have revealed a considerable number of differentially expressed genes, some of which appear to be specific to mechanical signal transduction. These genes can thus serve as markers of mechanosensing, for example, in studies attempting to define signalling threshold, or variations of mechanosensitivity (accommodation). Quantitative biomechanical studies have lead to a model of mechanoperception which links mechanical state and plant responses, and provides an integrative tool to study the regulation of mechanosensing. This model includes parameters (sensitivity and threshold) that can be estimated experimentally. It has also been shown that plants are desensitized when exposed to multiple mechanical signals as a function of their mechanical history. Finally, mechanosensing is also involved in osmoregulation or cell expansion. The links between these different processes involving mechanical signalling need further investigation. This frontier research topic provides an overview of the different aspects of mechanical signaling in plants, spanning perception, effects on plant growth and morphogenesis, and broad ecological significance.

Physiological Adaptations to Swimming in Fish

Authors: --- ---
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889452460 Year: Pages: 88 DOI: 10.3389/978-2-88945-246-0 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Physiology --- Oceanography
Added to DOAB on : 2018-02-27 16:16:44
License:

Loading...
Export citation

Choose an application

Abstract

Swimming is an integral part of the life history of many fish species as is intimately linked with their ability to express feeding and predator avoidance behaviors, habitat selection and environmental preferences, social and reproductive behaviors as well as migratory behaviors. Therefore, swimming is an important determinant factor of fitness in a true Darwinian sense and, not surprisingly, swimming performance has been often used as a measure of physiological fitness in fish. The main aim of this Research Topic is to showcase some of the current studies designed to improve our understanding of the physiological energetic and metabolic requirements of swimming and of the adaptive responses to swimming in fish.

Nutrition in Pregnancy - Volume II

Authors: ---
ISBN: 9783038423690 9783038423683 Year: Pages: XX, 270 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Medicine (General)
Added to DOAB on : 2017-04-28 10:21:23
License:

Loading...
Export citation

Choose an application

Abstract

Maternal nutrition during pregnancy is of considerable interest to women, their partners and their health care professionals. In developing countries, maternal undernutrition is a major concern. However, with the increased prevalence of abundant high calorie diets, their impact upon pregnancy outcome is of concern. In addition to the amount of nutrition available and its macronutrient composition within a diet, there is emerging evidence highlighting important roles for the lesser studied micronutrients. Added to this complexity is the distinction between maternal and fetal nutrition and the impact the placenta plays in nutrient metabolism and overall nutrient supply to the fetus. Together, these many variables contribute to placental development and function, fetal growth, and, where placental/fetal nutrition and growth is compromised, through poor maternal diet, and/or diet induced alterations in placental metabolism, the impact is dramatic and can lead to lifelong implications for the offspring. This Special Issue book aims to highlight research in many of these areas.

Growth, Employment, and Poverty in Latin America

Authors: --- --- ---
Book Series: WIDER Studies in Development Economics ISBN: 9780198801085 Year: Pages: 528 DOI: 10.1093/oso/9780198801085.001.0001 Language: English
Publisher: Oxford University Press Grant: UNU WIDER
Subject: Economics
Added to DOAB on : 2017-05-24 11:01:59
License:

Loading...
Export citation

Choose an application

Abstract

This book examines the links between economic growth, changing employment conditions, and the reduction of poverty in Latin America in the 2000s. Our analysis answers the following broad questions: Has economic growth resulted in gains in standards of living and reductions in poverty via improved labour market conditions in Latin America in the 2000s, and have these improvements halted or been reversed since the international crisis of 2008? How do the rate and character of economic growth, changes in the various employment and earnings indicators, and changes in poverty and inequality indicators relate to each other? Our contribution is an in-depth study of the multi-pronged growth-employment-poverty nexus based on a large number of labour market indicators (twelve employment and earnings indicators and four poverty and inequality indicators) for a large number of Latin American countries (sixteen of them). The book presents a positive and hopeful set of findings for the period 2000 to 2012/13. Economic growth took place and brought about improvements in almost all labour market indicators and consequent reductions in poverty rates. But not all improvements were equal in size or caused by the same things. Some macroeconomic factors were associated with changes in labour market conditions, some of them always in the welfare-improving direction and some others always in the welfare-reducing direction. Most countries in the region suffered a deterioration in at least some labour market indicators as a consequence of the international crisis of 2008, but the negative effects were reversed very quickly in most countries.

Tavoitteena sujuva arki

Authors: --- ---
ISBN: 9789520306106 9789520306090 Year: Pages: 254 Language: Finnish
Publisher: Tampere University Press
Subject: Sociology
Added to DOAB on : 2017-11-30 11:02:29
License:

Loading...
Export citation

Choose an application

Abstract

The growth of cultural diversity in Finnish social and health care workplaces challenges to develop not only ways of working and interaction but also organizational structures. Work communities as a whole are facing new challenges. The aim of this book is to help work communities develop well-functioning practices for intercultural work. Effective interaction between cultures provides the foundation not only for the well-being of staff and customers, but also for the financial success of the organization. The paper presents five action studies in the social and health care organization, which analyzed the abrasion points of everyday interaction, developed functional practices and corrective measures, and evaluated the effects of interventions. The aim of the project was to bring about structural reforms in support of inter-cultural work, since only the changes would become permanent.

Has Latin American Inequality Changed Direction?: Looking Over the Long Run

Authors: ---
ISBN: 9783319446202 9783319446219 Year: Pages: 419 DOI: 10.1007/978-3-319-44621-9 Language: English
Publisher: Springer Nature
Subject: Manufactures --- Economics --- Business and Management
Added to DOAB on : 2017-03-14 12:17:48
License:

Loading...
Export citation

Choose an application

Abstract

This book brings together a range of ideas and theories to arrive at a deeper understanding of inequality in Latin America and its complex realities. To so, it addresses questions such as: What are the origins of inequality in Latin America? How can we create societies that are more equal in terms of income distribution, gender equality and opportunities? How can we remedy the social divide that is making Latin America one of the most unequal regions on earth? What are the roles played by market forces, institutions and ideology in terms of inequality?In this book, a group of global experts gathered by the Institute for the Integration of Latin America and the Caribbean (INTAL), part of the Inter-American Development Bank (IDB), show readers how various types of inequality, such as economical, educational, racial and gender inequality have been practiced in countries like Brazil, Bolivia, Chile, Mexico and many others through the centuries.Presenting new ideas, new evidence, and new methods, the book subsequently analyzes how to move forward with second-generation reforms that lay the foundations for more egalitarian societies. As such, it offers a valuable and insightful guide for development economists, historians and Latin American specialists alike, as well as students, educators, policymakers and all citizens with an interest in development, inequality and the Latin American region.

Harnessing Useful Rhizosphere Microorganisms for Pathogen and Pest Biocontrol

Authors: --- ---
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889450596 Year: Pages: 334 DOI: 10.3389/978-2-88945-059-6 Language: English
Publisher: Frontiers Media SA
Subject: Botany --- Microbiology --- Science (General)
Added to DOAB on : 2017-07-06 13:27:36
License:

Loading...
Export citation

Choose an application

Abstract

Growing demographic trends require sustainable technologies to improve quality and yield of future food productions. However, there is uncertainty about plant protection strategies in many agro-ecosystems. Pests, diseases, and weeds are overwhelmingly controlled by chemicals which pose health risks and cause other undesirable effects.Therefore, an increasing concern on control measures emerged in recent years. Many chemicals became questioned with regard to their sustainability and are (or will be) banned. Alternative management tools are studied, relying on biological, and low impact solutions. This ResearchTopic concerns microbial biocontrol agents, root-associated microbiomes, and rhizosphere networks. Understanding how they interact or respond to (a)biotic environmental cues is instrumental for an effective and sustainable impact. The rhizosphere is in this regard a fundamental object of study, because of its role in plant productivity. This e-book provides a polyhedral perspective on many issues in which beneficial microorganisms are involved. Data indeed demonstrate that they represent an as yet poorly-explored resource, whose exploitation may actively sustain plant protection and crop production. Given the huge number of microbial species present on the planet, the microorganisms studied represent just the tip of an iceberg. Data produced are, however, informative enough about their genetic and functional biodiversity, as well as about the ecosystem services they provide to underp in crop production. Challenges for future research work concern not only the biology of these species, but also the practices required to protect their biodiversity and to extend their application in the wide range of agricultural soils and systems present in the world. Agriculture cannot remain successfully and sustainable unless plant germplasm and useful microbial species are integrated, a goal for which new knowledge and information-based approaches are urgently needed.Growing demographic trends require sustainable technologies to improve quality and yield of future food productions. However, there is uncertainty about plant protection strategies in many agro-ecosystems. Pests, diseases, and weeds are overwhelmingly controlled by chemicals which pose health risks and cause other undesirable effects.Therefore, an increasing concern on control measures emerged in recent years. Many chemicals became questioned with regard to their sustainability and are (or will be) banned. Alternative management tools are studied, relying on biological, and low impact solutions. This ResearchTopic concerns microbial biocontrol agents, root-associated microbiomes, and rhizosphere networks. Understanding how they interact or respond to (a)biotic environmental cues is instrumental for an effective and sustainable impact. The rhizosphere is in this regard a fundamental object of study, because of its role in plant productivity. This e-book provides a polyhedral perspective on many issues in which beneficial microorganisms are involved. Data indeed demonstrate that they represent an as yet poorly-explored resource, whose exploitation may actively sustain plant protection and crop production. Given the huge number of microbial species present on the planet, the microorganisms studied represent just the tip of an iceberg. Data produced are, however, informative enough about their genetic and functional biodiversity, as well as about the ecosystem services they provide to underp in crop production. Challenges for future research work concern not only the biology of these species, but also the practices required to protect their biodiversity and to extend their application in the wide range of agricultural soils and systems present in the world. Agriculture cannot remain successfully and sustainable unless plant germplasm and useful microbial species are integrated, a goal for which new knowledge and information-based approaches are urgently needed.

Advancements in Algal Biofuels Research - Recent Evaluation of Algal Biomass Production and Conversion Methods of into Fuels and High Value Co-products

Authors: ---
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889451982 Year: Pages: 81 DOI: 10.3389/978-2-88945-198-2 Language: English
Publisher: Frontiers Media SA
Subject: Biotechnology --- General and Civil Engineering
Added to DOAB on : 2017-10-13 14:57:01
License:

Loading...
Export citation

Choose an application

Abstract

Algae biomass has enormous potential to produce fuels and value-added products. Algae-derived biofuels and bioproducts offer great promise in contributing to U.S. energy security and in mitigating the environmental concerns associated with conventional fuels. Algae’s ability to grow in low quality water/wastewater and to accumulate lipids has encouraged scientists to investigate algae as a medium for wastewater treatment and a potential source of fuel and bioproducts. There are growing demands for biomass-based transportation fuels, including biodiesel, bio-oil, biomethane, biohydrogen, and other high-value products (nutraceuticals, proteins, omega-3 etc.). Algae can help address these needs. The topic of algae energy includes the production and characterization of algae cultures, conversion into fuel feedstocks and high value products, and optimization of product isolation and use. In view of the increasing efforts in algae biomass production and conversion into energy and high-value products, the current research topic covers important aspects of algal strain selection, culture systems, inorganic carbon utilization, lipid metabolism and quality, biomass harvesting, extraction of lipids and proteins, and thermochemical conversion of algal feedstocks into biocrude.

Smelly Fumes: Volatile-Mediated Communication between Bacteria and Other Organisms

Authors: --- --- ---
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889452224 Year: Pages: 227 DOI: 10.3389/978-2-88945-222-4 Language: English
Publisher: Frontiers Media SA
Subject: Microbiology --- Science (General)
Added to DOAB on : 2017-10-13 14:57:01
License:

Loading...
Export citation

Choose an application

Abstract

This e-book summarizes recent advances in the young and rapidly developing field of microbial volatiles. Articles included here reveal novel information about the chemical diversity of bacterial and fungal volatiles, their functions, their roles in inter-specific and inter-kingdom interactions and the metabolic and physiological changes their exposure causes in the target organisms. The e-book is divided in three chapters: (1) Natural Functions of Microbial Volatiles; (2) Volatile Production and Ecosystem Functioning and (3) Volatile Detection and Identification.

Listing 1 - 10 of 18 << page
of 2
>>
Sort by