scholarly journals Impact of Unsteady Flow Events on Bedload Transport: A Review of Laboratory Experiments

Water ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 907 ◽  
Author(s):  
Magdalena M. Mrokowska ◽  
Paweł M. Rowiński
Keyword(s):  
Unsteady Flow ◽  
Laboratory Experiments ◽  
Current Knowledge ◽  
Bedload Transport ◽  
Ephemeral Streams ◽  
Flow Conditions ◽  
Future Directions ◽  
Alluvial Rivers ◽  
Gravel Bed Streams ◽  
The Impact

Recent advances in understanding bedload transport under unsteady flow conditions are presented, with a particular emphasis on laboratory experiments. The contribution of laboratory studies to the explanation of key processes of sediment transport observed in alluvial rivers, ephemeral streams, and river reaches below a dam is demonstrated, primarily focusing on bedload transport in gravel-bed streams. The state of current knowledge on the impact of flow properties (unsteady flow hydrograph shape and duration, flood cycles) and sediment attributes (bed structure, sediment availability, bed composition) on bedload are discussed, along with unsteady flow dynamics of the water-sediment system. Experiments published in recent years are summarized, the main findings are presented, and future directions of research are suggested.

The Oxford Handbook of Hope

2017 ◽  
Keyword(s):  
Current Knowledge ◽  
Physical And Mental Health ◽  
Comprehensive Overview ◽  
Future Directions ◽  
Theoretical Perspectives ◽  
The Many ◽  
The Impact ◽  
Made In

The Oxford Handbook of Hope provides a comprehensive overview of current knowledge regarding the science and practice of hope. Hope has long been a topic of interest to philosophers and the general public, but it was only in recent decades that hope became a focus of psychological science. Rick Snyder defined hope as a cognitive trait that helps individuals to identify and pursue goals and consists of two components: pathways, the perceived capacity to identify strategies necessary to achieve goals, and agency, the willpower or motivation to pursue those pathways to achieve goals. Hope has become one of most robust and promising topics in the burgeoning field of positive psychology. This book reviews the progress that has been made in the past 25 years regarding the origins and influence of hope. Topics covered include current theoretical perspectives on how best to define hope and how it is distinct from related constructs, current best practices for measuring and quantifying hope, interventions and strategies for promoting hope across different settings and the lifespan, the impact that hope has on many dimensions and domains of physical and mental health, and the many ways and contexts in which hope promotes resilience and positive functioning. Experts in the field both review what is currently known about the role of hope in different domains and identify topics and questions that can help to guide the next decade of research. The handbook concludes with a collaborative vision on the future directions of the science of hope.

scholarly journals Nanoplastic Impact on the Gut-Brain Axis: Current Knowledge and Future Directions

2021 ◽  
Vol 22 (23) ◽  
pp. 12795
Author(s):  
Wojciech Grodzicki ◽  
Katarzyna Dziendzikowska ◽  
Joanna Gromadzka-Ostrowska ◽  
Marcin Kruszewski
Keyword(s):  
Current Knowledge ◽  
Intestinal Barrier ◽  
Plastic Pollution ◽  
Behavioral Disturbances ◽  
Future Directions ◽  
Human Environment ◽  
Synthetic Materials ◽  
Significant Burden ◽  
The Impact ◽  
The Brain

The widespread usage of plastic places a significant burden on the environment and impacts numerous aquatic and terrestrial species. Humans in particular can be affected by plastic pollution, predominantly via inhalation and ingestion, as well as trophic transfer along the food chain. Under natural conditions synthetic materials undergo degradation into micro- and nanoparticles, especially prone to interact with biological systems. Organisms exposed to nanoplastic accumulate it in multiple tissues, including the gut and the brain. This phenomenon raises a question about the impact of nanoparticulate plastics on the communication pathways between these organs. The aim of this review is to explore an unsettling possibility of the influence of nanoplastic on the gut-brain axis and provide a comprehensive summary of available data regarding this subject. The scarce but consistent evidence shows that exposure to plastic nanoparticles can indeed affect both the digestive and the nervous system. Reported outcomes include microbiota alterations, intestinal barrier permeability, oxidative stress, inflammation, neurotoxicity and behavioral disturbances. Taking into consideration these alarming observations and the ubiquitous presence of plastics in human environment, more research is urgently needed in order to identify any potential threats that nanoplastic exposure can pose to the functioning of the gut-brain axis.

scholarly journals Lifecycle cost optimization of pipeline projects

2020 ◽  
Vol 69 (7) ◽  
pp. 656-667
Author(s):  
Abdulrahman Al-Khomairi ◽  
BongSeog Jung ◽  
Ibrahim Elsebaie
Keyword(s):  
Unsteady Flow ◽  
Cost Optimization ◽  
Pipe Diameter ◽  
Pipe Material ◽  
Flow Conditions ◽  
Surge Tank ◽  
Cost Component ◽  
Wide Range ◽  
Optimum Solution ◽  
The Impact

Abstract Lifecycle cost optimization for a pipeline network with medium-sized pipes is performed considering steady and unsteady flow conditions. Genetic algorithms are used to generate a wide range of hydraulically acceptable solutions and search for the most economical solutions. The impact of each cost component on the total cost is determined in this study. The decision variables include the pipe diameter, pipe material, pipe pressure rating, surge tank size and operational and maintenance costs over the project service life. A real-case project is presented to crosscheck the suggested procedure. Significant cost variations are observed, even between equally acceptable designs. Furthermore, the operational cost has a deterministic effect on the parameters of the optimum solution. Compared to conventional design wisdom that focuses on reducing the pipe diameter as much as possible to reduce the project cost, this approach demonstrates that significant savings in pipeline project costs can be achieved by carefully investigating all possible design alternatives under steady and unsteady flow conditions.

Translating Principles of Speech Science to Clinical Practice: Current and Future Trends in Craniofacial Disorders

2008 ◽  
Vol 18 (1) ◽  
pp. 31-40 ◽  
Author(s):  
David J. Zajac
Keyword(s):  
Clinical Practice ◽  
Speech Intelligibility ◽  
Current Practice ◽  
Computer Assisted ◽  
Behavioral Management ◽  
Single Word ◽  
Future Directions ◽  
Speech Science ◽  
The Impact ◽  
Opinion Article

Abstract The purpose of this opinion article is to review the impact of the principles and technology of speech science on clinical practice in the area of craniofacial disorders. Current practice relative to (a) speech aerodynamic assessment, (b) computer-assisted single-word speech intelligibility testing, and (c) behavioral management of hypernasal resonance are reviewed. Future directions and/or refinement of each area are also identified. It is suggested that both challenging and rewarding times are in store for clinical researchers in craniofacial disorders.

Free Fatty Acid Receptors as New Potential Targets in Colorectal Cancer

2020 ◽  
Vol 21 (14) ◽  
pp. 1397-1404
Author(s):  
Adrian Bartoszek ◽  
Jakub Fichna ◽  
Aleksandra Tarasiuk ◽  
Agata Binienda ◽  
Adam Fabisiak ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Current Knowledge ◽  
Developed Countries ◽  
Future Directions ◽  
Screening Programs ◽  
Pharmacological Targets ◽  
The Family ◽  
Free Fatty Acid Receptors

Colorectal cancer (CRC) is one of the most common cancers worldwide. In developed countries, its mortality remains high, yet the prevalence has established owing to effective screening programs; however due to the westernization of lifestyle, the incidences in many other countries have increased. Although the treatment of CRC has improved in the last few years, the side effects of these approaches cannot be neglected. Recently, members of the family of free fatty acid receptors (FFARs) have become attractive pharmacological targets in many diseases, including asthma; studies also point to their role in carcinogenesis. Here, we discuss current knowledge and future directions in FFAR research related to CRC. Contradictory results of FFARs modulation may derive from the pleiotropic effects of FFAR ligands, receptor distribution and different signal transduction. Hence, we indicate directions of further studies to fully use the potential of FFARs in CRC.

Alcohol Consumption and Risk of Uterine Fibroids

2020 ◽  
Vol 20 (4) ◽  
pp. 247-258 ◽  
Author(s):  
Hajra Takala ◽  
Qiwei Yang ◽  
Ahmed M. Abd El Razek ◽  
Mohamed Ali ◽  
Ayman Al-Hendy
Keyword(s):  
Alcohol Consumption ◽  
Animal Studies ◽  
Molecular Mechanisms ◽  
Legal Status ◽  
Current Knowledge ◽  
Uterine Fibroids ◽  
Future Directions ◽  
Working Adults ◽  
The Us ◽  
Alcohol Related Problems

Lifestyle factors, such as alcohol intake, have placed a substantial burden on public health. Alcohol consumption is increasing globally due to several factors including easy accessibility of this addictive substance besides its legal status and social acceptability. In the US, alcohol is the third leading preventable cause of death (after tobacco, poor diet and physical inactivity) with an estimated 88,000 people dying from alcohol-related causes annually, representing 1 in 10 deaths among working adults. Furthermore, the economic burden of excess drinking costs the US around $249 billion ($191.1 billion related to binge drinking). Although men likely drink more than women do, women are at much higher risk for alcohol-related problems. Alcohol use is also considered to be one of the most common non-communicable diseases, which affects reproductive health. This review article summarizes the current knowledge about alcohol-related pathogenesis of uterine fibroids (UFs) and highlights the molecular mechanisms that contribute to the development of UFs in response to alcohol consumption. Additionally, the effect of alcohol on the levels of various factors that are involved in UFs pathogenesis, such as steroid hormones, growth factors and cytokines, are summarized in this review. Animal studies of deleterious alcohol effect and future directions are discussed as well.

From Silent Spring to The Frog of War

2017 ◽  
Author(s):  
David K. Skelly
Keyword(s):  
Natural History ◽  
Laboratory Experiments ◽  
Wild Populations ◽  
Rachel Carson ◽  
Chemical Agents ◽  
Silent Spring ◽  
The World ◽  
History Information ◽  
Wildlife Populations ◽  
The Impact

This chapter presents two examples to demonstrate that natural history is the necessary basis of any reliable understanding of the world. More than a half century ago, Rachel Carson revolutionized the public’s view of pesticides. The foundation of her success was the careful use of natural history data, collated from across North America. The examples she assembled left little doubt that DDT and other pesticides were causing a widespread decline in birds. More recently, the case for the impact of atrazine on wildlife was based on laboratory experiments, without the advantage of natural history observations. For atrazine, natural history observations now suggest that other chemical agents are more likely to be responsible for feminization of wildlife populations. Developing expectations for scientists to collect natural history information can help to avoid over-extrapolating lab results to wild populations, a tendency often seen when those lab results conform to preconceptions about chemicals in the environment.

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