Biogeomorphological research frontiers: from ant mounds to Mars

2020 ◽  
Author(s):  
Heather Viles
Keyword(s):  
High Risk ◽  
Spatial Scales ◽  
The Past ◽  
Scientific Controversies ◽  
Wide Range ◽  
Geomorphological Processes ◽  
Temporal And Spatial ◽  
Ecological Dimension ◽  
Research Frontiers ◽  
Ant Mounds

<p>Biogeomorphology is a vibrant area of scientific research which focuses on the two-way interrelationships between ecological and geomorphological processes across a wide range of temporal and spatial scales. Whilst ecological influences on geomorphology were often perceived in the past as a rather niche topic, most geomorphologists now  consider the ecological dimension as being crucial to the evolution and behaviour of geomorphological systems. However, there is still much to be done to explore the intersections between ecology and geomorphology. It is now timely to investigate what frontier research in biogeomorphology might look like over the coming years. This paper explores some characteristics of frontier research (addressing scientific controversies, focusing on hard-to-answer questions, employing atypical methods and concepts, being paradigm-challenging, and having a high risk of failure) in the context of tomorrow’s biogeomorphology. As examples, the paper addresses current progress in research on the geomorphological contributions of ants on Earth, and microbial biosignatures on Mars.</p>

scholarly journals The Value of Citizen Science in Increasing Our Knowledge of Under-Sampled Biodiversity: An Overview of Public Documentation of Auchenorrhyncha and the Hoppers of North Carolina

2021 ◽  
Vol 9 ◽  
Author(s):  
Kyle D. Kittelberger ◽  
Solomon V. Hendrix ◽  
Çağan Hakkı Şekercioğlu
Keyword(s):  
North Carolina ◽  
Citizen Science ◽  
Spatial Scales ◽  
The United States ◽  
Undescribed Species ◽  
The Past ◽  
Global Biodiversity ◽  
Temporal And Spatial

Due to the increasing popularity of websites specializing in nature documentation, there has been a surge in the number of people enthusiastic about observing and documenting nature over the past 2 decades. These citizen scientists are recording biodiversity on unprecedented temporal and spatial scales, rendering data of tremendous value to the scientific community. In this study, we investigate the role of citizen science in increasing knowledge of global biodiversity through the examination of notable contributions to the understanding of the insect suborder Auchenorrhyncha, also known as true hoppers, in North America. We have compiled a comprehensive summary of citizen science contributions—published and unpublished—to the understanding of hopper diversity, finding over fifty previously unpublished country and state records as well as dozens of undescribed and potentially undescribed species. We compare citizen science contributions to those published in the literature as well as specimen records in collections in the United States and Canada, illuminating the fact that the copious data afforded by citizen science contributions are underutilized. We also introduce the website Hoppers of North Carolina, a revolutionary new benchmark for tracking hopper diversity, disseminating knowledge from the literature, and incorporating citizen science. Finally, we provide a series of recommendations for both the entomological community and citizen science platforms on how best to approach, utilize, and increase the quality of sightings from the general public.

Arctic systems in the Quaternary: ecological collision, faunal mosaics and the consequences of a wobbling climate

2017 ◽  
Vol 91 (4) ◽  
pp. 409-421 ◽  
Author(s):  
E.P. Hoberg ◽  
J.A. Cook ◽  
S.J. Agosta ◽  
W. Boeger ◽  
K.E. Galbreath ◽  
...  
Keyword(s):  
Spatial Scales ◽  
Pathogen Transmission ◽  
Tipping Points ◽  
Climate Oscillations ◽  
The Past ◽  
Ecological Barriers ◽  
History Of ◽  
Temporal And Spatial ◽  
Time Frames ◽  
Faunal Assembly

AbstractClimate oscillations and episodic processes interact with evolution, ecology and biogeography to determine the structure and complex mosaic that is the biosphere. Parasites and parasite–host assemblages are key components in a general explanatory paradigm for global biodiversity. We explore faunal assembly in the context of Quaternary time frames of the past 2.6 million years, a period dominated by episodic shifts in climate. Climate drivers cross a continuum from geological to contemporary timescales and serve to determine the structure and distribution of complex biotas. Cycles within cycles are apparent, with drivers that are layered, multifactorial and complex. These cycles influence the dynamics and duration of shifts in environmental structure on varying temporal and spatial scales. An understanding of the dynamics of high-latitude systems, the history of the Beringian nexus (the intermittent land connection linking Eurasia and North America) and downstream patterns of diversity depend on teasing apart the complexity of biotic assembly and persistence. Although climate oscillations have dominated the Quaternary, contemporary dynamics are driven by tipping points and shifting balances emerging from anthropogenic forces that are disrupting ecological structure. Climate change driven by anthropogenic forcing has supplanted a history of episodic variation and is eliminating ecological barriers and constraints on development and distribution for pathogen transmission. A framework to explore interactions of episodic processes on faunal structure and assembly is the Stockholm Paradigm, which appropriately shifts the focus from cospeciation to complexity and contingency in explanations of diversity.

scholarly journals The Application of Complexity Analysis in Brain Blood-Oxygen Signal

2021 ◽  
Vol 11 (11) ◽  
pp. 1415
Author(s):  
Xiaoyang Xin ◽  
Shuyang Long ◽  
Mengdan Sun ◽  
Xiaoqing Gao
Keyword(s):  
Complexity Analysis ◽  
Spatial Scales ◽  
Blood Oxygen ◽  
Complexity Measures ◽  
Future Directions ◽  
Brain Physiology ◽  
Wide Range ◽  
Signal Complexity ◽  
Temporal And Spatial ◽  
The Brain

One of the daunting features of the brain is its physiology complexity, which arises from the interaction of numerous neuronal circuits that operate over a wide range of temporal and spatial scales, enabling the brain to adapt to the constantly changing environment and to perform various cognitive functions. As a reflection of the complexity of brain physiology, the complexity of brain blood-oxygen signal has been frequently studied in recent years. This paper reviews previous literature regarding the following three aspects: (1) whether the complexity of the brain blood-oxygen signal can serve as a reliable biomarker for distinguishing different patient populations; (2) which is the best algorithm for complexity measure? And (3) how to select the optimal parameters for complexity measures. We then discuss future directions for blood-oxygen signal complexity analysis, including improving complexity measurement based on the characteristics of both spatial patterns of brain blood-oxygen signal and latency of complexity itself. In conclusion, the current review helps to better understand complexity analysis in brain blood-oxygen signal analysis and provide useful information for future studies.

scholarly journals The implications of disconnectivity for the study of contemporary geomorphic processes

2017 ◽  
Vol 19 (1) ◽  
pp. 5-15
Author(s):  
SLAYMAKER Olav
Keyword(s):  
Human Activities ◽  
Spatial Scales ◽  
Scale Problem ◽  
Conservation Of Mass ◽  
Natural Processes ◽  
The Past ◽  
Temporal And Spatial ◽  
Spatio Temporal ◽  
Geomorphic Processes

The emphasis on the understanding of contemporary geomorphic processes that has dominated Anglophone geomorphological literature over the past 50 years has seen huge progress but also some set-backs. We now have reliable measurements of mean rates of operation of all subaerial processes responsible for modification of landforms and landscapes and have made good progress in estimating the role of human activities as compared with “natural” processes. Some limited progress has been achieved in understanding the scale problem but problems remain. Perhaps the single most surprising development has been the recognition of the ubiquity of disconnectivity in geomorphic systems, the need to calculate virtual velocities of whole geomorphic systems and the relevance of this understanding to the general spatio-temporal scale problem. We have always known that most geomorphic processes operate intermittently but we have continued to depend on models that imply that mass and energy move freely through geomorphic systems and that conservation of mass and energy occurrs uninterruptedly at all temporal and spatial scales.

scholarly journals Red noise in steady-state multiphase flow

2021 ◽  
Author(s):  
Catherine Spurin ◽  
Gaetano Garfi ◽  
Maja Rücker ◽  
Tom Bultreys ◽  
Samuel Krevor ◽  
...  
Keyword(s):  
Steady State ◽  
Multiphase Flow ◽  
Pore Space ◽  
Spatial Scales ◽  
Pressure Fluctuations ◽  
Subsurface Flow ◽  
Porous Rock ◽  
Wide Range ◽  
Temporal And Spatial ◽  
Continuous Range

Understanding the interaction between competing fluids in the pore space of rocks is key for predicting subsurface flow and trapping, such as with CO2 in a saline aquifer. These processes occur over a large span of timescales (from seconds to thousands of years), and length scales (from microns to kilometres). Understanding the link between these temporal and spatial scales will enable us to interpolate between observations made at different resolutions. In this work we explore the temporal scales present during macroscopically steady-state multiphase flow in a porous rock using differential pressure measurements. We observe a cascade of timescales in the pressure differential i.e. a continuous range of frequencies, with lower frequencies having greater amplitudes. We demonstrate a scaling of the spectral density with frequency of S ∼ 1/f^2, or red noise, to describe the dynamics. This scaling is independent of the flow rate of the fluids or the fraction of the flow taken by water. This red, or Brownian, noise indicates a stochastic process where pressure fluctuations are seen throughout the pore space, resulting in intermittent filling of pores over a wide range of time-scales, from seconds to minutes in these experiments. This observation will aid future modelling of subsurface flow as it suggests self-organised critically of the system with no characteristic time or length scale.

Development and Application of a Storage Model for River Flow Forecasting

1983 ◽  
Vol 14 (3) ◽  
pp. 139-154 ◽  
Author(s):  
Takeshi Hata ◽  
Malcolm G. Anderson
Keyword(s):  
River Flow ◽  
Spatial Scales ◽  
Forecasting Model ◽  
Data Input ◽  
Storage Model ◽  
Topographic Data ◽  
River Flow Forecasting ◽  
Wide Range ◽  
Temporal And Spatial

A lumped sequential river flow forecasting model is outlined. It is shown to be flexible in both temporal and spatial scales, thereby allowing simulations to be undertaken for a wide range of practical purposes. In addition, the required data input is very low, and is restricted to topographic data for only small segments of the entire catchment. The model is successfully applied to the River Avon in England and the River Kako in Japan.

Putting Capitalism in Its Place: Economies of Worth and the Practice of Australian History

2021 ◽  
Vol 121 (1) ◽  
pp. 195-217
Author(s):  
Frances Flanagan ◽  
Ben Huf
Keyword(s):  
Social Order ◽  
Economic History ◽  
Common Good ◽  
Spatial Scales ◽  
New Left ◽  
History Of Capitalism ◽  
The Past ◽  
History Of ◽  
The Common ◽  
Temporal And Spatial

Writing histories of capitalism involves making decisions about how to contextualise the wider non-capitalist formations that underpin and sustain capitalist processes. This article introduces Boltanski and Thévenot’s economies of worth (EW) framework as a tool and stimulus for historians to historicise capitalism as a social order while simultaneously avoiding the determinism of concepts such as commodification and capitalist accumulation. The article identifies four dominant approaches to contextualisation of capitalism in Australia in the past: economic history, radical nationalism, the New Left and settler capitalism. It then introduces EW, a repertoire of competing conceptions of the common good that, we argue, offers a framework for systematically drawing contested, hybrid and co-existent forms of capitalist and non-capitalist value, or “worth,” into view across multiple temporal and spatial scales. The potential usefulness of this framework is illustrated through a discussion of recent scholarship in the history of capitalism in Australia.

Temporal and Spatial Variations of Atmospheric CO2 Growth reproduced by Ground-Based Remote Sensing and CO2 Inverse Modelling

2020 ◽  
Author(s):  
Lev Labzovskii ◽  
Samuel Takele Kenea ◽  
Jinwon Kim ◽  
Young-Hwa Byun ◽  
Tae-Young Goo ◽  
...  
Keyword(s):  
El Niño ◽  
El Nino ◽  
Spatial Scales ◽  
Central Africa ◽  
Global Scale ◽  
Spatial Variations ◽  
Temporal And Spatial Variations ◽  
Spatial Coverage ◽  
Wide Range ◽  
Temporal And Spatial

<p>Atmospheric CO<sub>2</sub> growth rate is the primary driver of the global warming and a valuable indicator of the interannual changes in carbon cycle. We broaden the knowledge about temporal and spatial variations of annual CO<sub>2</sub> growth (AGR) by using CO<sub>2</sub> observations from the Total Column Observing Network (TCCON), CO<sub>2</sub> simulations from Carbon Tracker (CT) and Copernicus Atmospheric Monitoring System (CAMS) models together with the global-scale AGR references from Global Carbon Budget (GCB) and satellite data (SAT) for 2004-2019 years. TCCON and the CO<sub>2</sub> models reveal temporal AGR variations (AGR<sub>TCCON</sub> = 1.71 – 3.35 ppm, AGR<sub>CT</sub> = 1.59 – 3.30 ppm, AGR<sub>CAMS</sub> = 1.66 – 3.13 ppm) of the similar magnitude to the global-scale CO<sub>2</sub> growth references (AGR<sub>GCB</sub> = 1.59 – 3.23 ppm, AGR<sub>SAT</sub> = 1.55 – 2.92 ppm). However, TCCON estimates of global AGR agree well with the referenced AGR growth only during the 2010s since the network has considerably improved its spatial coverage after 2009. Moreover, TCCON-based AGRs reasonably agree (r = 0.67) with strength of El Nino Southern Oscillations (ENSO) in the 2010s. The highest atmospheric CO<sub>2</sub> growth (2015-2016) driven by the very strong El-Nino event is accurately reproduced by TCCON that provided AGR of 2015-2016 years (3.29 ± 0.98 ppm) in very close agreement to the SAT reference (3.23 ± 0.50 ppm). We validate CAMS and CT simulations of AGR versus the newly-acquired TCCON-based AGR (as the point-location reference) for an every single TCCON site and low agreement (r < 0.50) is evidenced only at 3 out of 20 stations. This minor caveat has not affected the accuracy of simulated global AGR since it exhibits high agreement with SAT, GCB (r = 0.74 – 0.78) and TCCON (r > 0.65) references at global scales. Moreover, the correlation of AGR simulations across all grid cells (3 x 2 degree) between CAMS and CT is nearly perfect (r = 0.95) for the modeling period (2004-2016). Similarly, land-wise AGR intercomparison between CAMS and CT yields in perfect correlation (r ≧ 0.90) for 15 out of 20 MODIS land classes where the least vegetated areas exhibit the highest agreement. From spatial perspective, the highest AGR estimates (> 20% from the median value) are observed in the regions with intense combustion (East Asia) or with frequent biomass burning (Amazon, Central Africa). The slight disagreement of AGR spatial variability simulated by CT and CAMS is likely driven by the latter two regions of SH where drier conditions during El-Nino events allegedly increase the probability for divergence between the models. In overall, the current estimates of global AGR are consistent across a wide range of the data sources and strengthening of CO<sub>2</sub> observational infrastructure should further improve the accuracy of AGR estimates on global and fine spatial scales.</p>

Optical Properties of HVEM Accelerators

1975 ◽  
Vol 33 ◽  
pp. 180-181
Author(s):  
A. Strojnik ◽  
J.W. Scholl ◽  
V. Bevc
Keyword(s):  
Optical Properties ◽  
Electron Accelerator ◽  
Systematic Investigation ◽  
Electron Source ◽  
High Brightness ◽  
The Past ◽  
Wide Range ◽  
Optical Behavior

The electron accelerator, as inserted between the electron source (injector) and the imaging column of the HVEM, is usually a strong lens and should be optimized in order to ensure high brightness over a wide range of accelerating voltages and illuminating conditions. This is especially true in the case of the STEM where the brightness directly determines the highest resolution attainable. In the past, the optical behavior of accelerators was usually determined for a particular configuration. During the development of the accelerator for the Arizona 1 MEV STEM, systematic investigation was made of the major optical properties for a variety of electrode configurations, number of stages N, accelerating voltages, 1 and 10 MEV, and a range of injection voltages ϕ0 = 1, 3, 10, 30, 100, 300 kV).

1610: High-Risk Patients Undergoing Radical Prostatectomy Today are Less High-Risk than in the Past

2005 ◽  
Vol 173 (4S) ◽  
pp. 436-436
Author(s):  
Christopher J. Kane ◽  
Martha K. Terris ◽  
William J. Aronson ◽  
Joseph C. Presti ◽  
Christopher L. Amling ◽  
...  
Keyword(s):  
High Risk ◽  
Radical Prostatectomy ◽  
High Risk Patients ◽  
The Past ◽  
Risk Patients
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