scholarly journals Supplemental Material: Evidence for enhanced fluvial channel mobility and fine sediment export due to precipitation seasonality during the Paleocene-Eocene thermal maximum

2021 ◽  
Author(s):  
Eric Barefoot ◽  
et al.
Keyword(s):  
Data File ◽  
Fine Sediment ◽  
Field Methods ◽  
Channel Mobility ◽  
Detailed Explanation ◽  
Thermal Maximum ◽  
Precipitation Seasonality ◽  
Sediment Export ◽  
Future Work ◽  
Material Evidence

A more-detailed explanation of the field methods used to collect the data for this study, and the statistical tools used to analyze the data, in addition to a description of how the data file is organized. This information should be applied in conjunction with the data and code if readers are interested in using these data for future work.<br>

scholarly journals Supplemental Material: Evidence for enhanced fluvial channel mobility and fine sediment export due to precipitation seasonality during the Paleocene-Eocene thermal maximum

2021 ◽  
Author(s):  
Eric Barefoot ◽  
et al.
Keyword(s):  
Data File ◽  
Fine Sediment ◽  
Field Methods ◽  
Channel Mobility ◽  
Detailed Explanation ◽  
Thermal Maximum ◽  
Precipitation Seasonality ◽  
Sediment Export ◽  
Future Work ◽  
Material Evidence

A more-detailed explanation of the field methods used to collect the data for this study, and the statistical tools used to analyze the data, in addition to a description of how the data file is organized. This information should be applied in conjunction with the data and code if readers are interested in using these data for future work.<br>

scholarly journals Evidence for enhanced fluvial channel mobility and fine sediment export due to precipitation seasonality during the Paleocene-Eocene thermal maximum

Geology ◽  
2021 ◽  
Author(s):  
Eric A. Barefoot ◽  
Jeffrey A. Nittrouer ◽  
Brady Z. Foreman ◽  
Elizabeth A. Hajek ◽  
Gerald R. Dickens ◽  
...  
Keyword(s):  
Climate Models ◽  
Water Discharge ◽  
Experimental Studies ◽  
Fine Sediment ◽  
Sediment Flux ◽  
Mean Annual Precipitation ◽  
Fluvial Sediment ◽  
Channel Mobility ◽  
Thermal Maximum ◽  
Precipitation Seasonality

The Paleocene-Eocene thermal maximum (PETM) was the most extreme example of an abrupt global warming event in the Cenozoic, and it is widely discussed as a past analog for contemporary climate change. Anomalous accumulation of terrigenous mud in marginal shelf environments and concentration of sand in terrestrial deposits during the PETM have both been inferred to represent an increase in fluvial sediment flux. A corresponding increase in water discharge or river slope would have been required to transport this additional sediment. However, in many locations, evidence for changes in fluvial slope is weak, and geochemical proxies and climate models indicate that while runoff variability may have increased, mean annual precipitation was unaffected or potentially decreased. Here, we explored whether changes in river morphodynamics under variable-discharge conditions could have contributed to increased fluvial sand concentration during the PETM. Using field observations, we reconstructed channel paleohydraulics, mobility, and avulsion behavior for the Wasatch Formation (Piceance Basin, Colorado, USA). Our data provide no evidence for changes in fluvial slope during the PETM, and thus no evidence for enhanced sediment discharge. However, our data do show evidence of increased fluvial bar reworking and advection of sediment to floodplains during channel avulsion, consistent with experimental studies of alluvial systems subjected to variable discharge. High discharge variability increases channel mobility and floodplain reworking, which retains coarse sediment while remobilizing and exporting fine sediment through the alluvial system. This mechanism can explain anomalous fine sediment accumulation on continental shelves without invoking sustained increases in fluvial sediment and water discharge.

Multiparticle Effective Field and Related Methods in Micromechanics of Composite Materials

2001 ◽  
Vol 54 (1) ◽  
pp. 1-47 ◽  
Author(s):  
V. A. Buryachenko
Keyword(s):  
Composite Materials ◽  
Perturbation Methods ◽  
Infinite System ◽  
Effective Field ◽  
Field Methods ◽  
System Of Integral Equations ◽  
Linear Elastic ◽  
Self Consistent ◽  
Future Work ◽  
Graded Structures

The numerous approaches used in micromechanics can be classified into four broad categories: perturbation methods, self-consistent methods of truncation of a hierarchy, variational methods, and the model methods. In detail we will consider the self-consistent methods applied to linear elastic problems, based on some approximate and closing assumptions for truncating of an infinite system of integral equations involved and their approximate solution. We consider multiparticle effective field methods, effective medium methods, the Mori-Tanaka method, differential methods and some others. This review article tends to concentrate on methods and concepts, their possible generalizations, and connections of different methods, rather than explicit results. In the framework of a unique scheme, we undertake an attempt to analyze the wide class of statical and dynamical, local and nonlocal, linear and nonlinear micromechanical problems of composite materials with deterministic (periodic and non-periodic) and random (statistically homogeneous and inhomogeneous, so-called graded) structures, containing coated or uncoated inclusions of any shape and orientation and subjected to coupled or uncoupled, homogeneous or inhomogeneous, external fields of different physical natures. The last section contains a discussion of prospects for future work. The article includes 540 references.

scholarly journals The OpenNebula Cloud Toolkit

2011 ◽  
pp. 19-43 ◽  
Author(s):  
Daniel Molina ◽  
Carlos Martín Sánchez ◽  
Jaime Melis ◽  
Javier Fontán ◽  
Constantino Vázquez ◽  
...  
Keyword(s):  
Research And Development ◽  
Large Scale ◽  
Virtual Machines ◽  
Lessons Learned ◽  
Use Case ◽  
Distributed Management ◽  
Detailed Explanation ◽  
Physical Resources ◽  
History Of ◽  
Future Work

This chapter aims to describe the OpenNebula Cloud Toolkit, a framework born as a result of many years of research and development that intends to provide an efficient and scalable solution for the large-scale distributed management of Virtual Machines running on a pool of physical resources. A description of the history of the project is presented, along with a detailed explanation of the characteristics of the Toolkit, including directions on how to install and configure the software, enumeration of the interfaces exposed, and information on how to use and configure the three types of clouds (private, hybrid, and public) that can be built with the framework. The chapter ends with a practical use case that shows how to deploy a service composed of Virtual Machines on top of an OpenNebula cloud, and with the lessons learned during the project and the future work planned for the Toolkit.

scholarly journals Health information behavior of speakers of endangered languages

2020 ◽  
Vol 52 (4) ◽  
pp. 1042-1049
Author(s):  
Mary Burke
Keyword(s):  
Health Information ◽  
Information Behavior ◽  
Indigenous Communities ◽  
Information Resources ◽  
Endangered Languages ◽  
Field Methods ◽  
Language Endangerment ◽  
Ethnographic Interviews ◽  
Health Information Resources ◽  
Future Work

With the advent of increased attention towards language endangerment comes the need for a better understanding of how speakers of endangered languages interact with information, specifically health information resources. This paper builds on health information behavior literature and participatory research models with indigenous communities to develop strategies for future work with indigenous communities of speakers of endangered languages, proposing a participatory methodology for future work with these communities related to health, using ethnographic interviews and focus groups. Lack of infrastructure, multilingualism, and distrust of outsiders are found to be major barriers between this population and health information resources. Approaching health information behavior research with an interdisciplinary and participatory model incorporating ethnographic and linguistic field methods into traditional information behavior methodologies can mitigate the challenges these barriers present. Understanding the health information behavior of speakers of endangered languages will aid in future efforts to make health information resources accessible to wider audiences and to document indigenous knowledge. Currently, fieldwork with speakers of endangered languages is confined to linguistic and anthropological investigation. Through the proposed methodology, community members can work alongside linguists and information professionals to create culturally appropriate health information resources in their native language.

Catchment scale simulations of the climatic regulation of fine sediment evacuation after widespread landsliding

2020 ◽  
Author(s):  
Thomas Croissant ◽  
Robert Hilton ◽  
Dimitri Lague ◽  
Alexander Densmore ◽  
Jamie Howarth ◽  
...  
Keyword(s):  
New Zealand ◽  
Temporal Dynamics ◽  
Water Discharge ◽  
Sediment Concentration ◽  
Fine Sediment ◽  
Sediment Supply ◽  
Storm Events ◽  
Catchment Scale ◽  
Relaxation Phase ◽  
Sediment Export

&lt;p&gt;In mountain ranges, widespread landsliding triggered by large earthquakes can mobilise large amounts of non-cohesive sediment and organic matter that can be transported by rivers during the post-seismic landscape relaxation phase. The timescales over which this occurs are likely to be decades, meaning that it is difficult to establish the controls on post-seismic sediment evacuation from modern-day case studies. River gauging station data, reservoir and lake sediments have been helpful to constrain the temporal dynamics of fine sediment evacuation. However, key unknowns remain, particularly with regard to the competition between sediment supply and river transport capacity in space and time. Here, we attempt to tackle this using a 2D morphodynamic approach by applying the numerical model Eros at the catchment scale. We aim to systematically investigate how the properties of landslide populations and the runoff intensity and variability combine to control fine sediment export as suspended load from storm events to years and decades. Our focus is on the Potters Creek catchment located in the Southern Alps of New Zealand, where the Alpine Fault can generate Mw 8 earthquakes and which has one of the highest precipitation rates measured in the world. The chosen tectonic scenarios encompass different earthquake shaking intensities that translate to various landslide densities. Landslide properties are randomly sampled from empirical scaling relationships and the mobilised sediment is introduced in the landscape using a runout algorithm. The runoff distribution is constrained by empirical data and applied as climate forcing of the simulations. Prior to the quantification of the sediment export, we set up a calibration phase to constrain the sediment entrainment and deposition laws against data measured in the West Coast of New Zealand. Subsequently, an exploration phase is developed to quantify the sediment evacuation sensitivity to climatic parameters and the earthquake-derived landslide distribution properties. We find that the post-seismic sediment discharge is strongly controlled by the amount of sediment supplied and the accessibility of the sediment to fluvial transport. These two properties control the power-law scaling relationship (intercept and slope) between daily sediment concentration and water discharge. Runoff intensity and the sequence of discharge events plays a central role on the export velocity of the fine sediment. Simulations show that fine sediment transport can rapidly (with year) return to apparent pre-disturbance levels, before experiencing a renewed wave of sediment at the catchment outlet from more distal sources. These simulations provide new insight on the common controls and complexities of the evacuation of fine sediment from earthquake-triggered landslides.&lt;/p&gt;

Present status of radio astrometry with baselines ≤ 35 km

1978 ◽  
Vol 48 ◽  
pp. 175-178 ◽  
Author(s):  
K. J. Johnston
Keyword(s):  
Present Status ◽  
Future Work

A summary of results for radio astrometry with baselines ≤ 35 km and priorities for future work are given.

Near-field scanning optical microscopy

1986 ◽  
Vol 44 ◽  
pp. 642-643
Author(s):  
E. Betzig ◽  
A. Harootunian ◽  
M. Isaacson ◽  
A. Lewis
Keyword(s):  
Near Field ◽  
Optical Microscope ◽  
Visible Radiation ◽  
Field Methods ◽  
Optical Elements ◽  
Optical Region ◽  
Order Of Magnitude ◽  
Nondestructive Imaging ◽  
Scanning Optical Microscopy ◽  
Near Field Scanning

In general, conventional methods of optical imaging are limited in spatial resolution by either the wavelength of the radiation used or by the aberrations of the optical elements. This is true whether one uses a scanning probe or a fixed beam method. The reason for the wavelength limit of resolution is due to the far field methods of producing or detecting the radiation. If one resorts to restricting our probes to the near field optical region, then the possibility exists of obtaining spatial resolutions more than an order of magnitude smaller than the optical wavelength of the radiation used. In this paper, we will describe the principles underlying such "near field" imaging and present some preliminary results from a near field scanning optical microscope (NS0M) that uses visible radiation and is capable of resolutions comparable to an SEM. The advantage of such a technique is the possibility of completely nondestructive imaging in air at spatial resolutions of about 50nm.

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