Imprints of Ocean Chaotic Intrinsic Variability on Bottom Pressure and Implications for Data and Model Analyses

Soft-tissue sarcomas are rare tumors characterized by pathogenetic, morphological, and clinical intrinsic variability. Median survival of patients with advanced tumors are usually chemo- and radio-resistant, and standard treatments yield low response rates and poor survival results. The identification of defined genomic alterations in sarcoma could represent the premise for targeted treatments. Summarizing, soft-tissue sarcomas can be differentiated into histotypes with reciprocal chromosomal translocations, with defined oncogenic mutations and complex karyotypes. If the latter are improbably approached with targeted treatments, many suggest that innovative therapies interfering with the identified fusion oncoproteins and altered pathways could be potentially resolutive. In most cases, the characteristic genetic signature is discouragingly defined as “undruggable”, which poses a challenge for the development of novel pharmacological approaches. In this review, a summary of genomic alterations recognized in most common soft-tissue sarcoma is reported together with current and future therapeutic opportunities.

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Critical Review of EMC Standards for the Measurement of Radiated Electromagnetic Emissions from Transit Line and Rolling Stock

Energies ◽

10.3390/en14030759 ◽

2021 ◽

Vol 14 (3) ◽

pp. 759

Author(s):

Andrea Mariscotti

Keyword(s):

Time Distribution ◽

Communication Systems ◽

Electromagnetic Compatibility ◽

Transportation Systems ◽

Operating Conditions ◽

Rolling Stock ◽

Intrinsic Variability ◽

Statistical Characterization ◽

Electromagnetic Emissions

Accurate and comprehensive methods for the assessment of radiated electromagnetic emissions in modern electric transportation systems are a necessity. The characteristics and susceptibility of modern victim signaling and communication radio services, operating within and outside the right-of-way, require an update of the measurement methods integrating or replacing the swept frequency technique with time domain approaches. Applicable standards are the EN 50121 (equivalent to the IEC 62236) and Urban Mass Transport Association (UMTA) with additional specifications from project contracts. This work discusses the standardized methods and settings, and the representative operating conditions, highlighting areas where improvements are possible and opportune (statistical characterization of measurement results, identification and distinction of emissions and line resonances, and narrowband and broadband phenomena). In particular for the Electromagnetic Compatibility (EMC) assessment with new Digital Communication Systems, the characterization of time distribution of spectral properties is discussed, e.g., by means of Amplitude Probability Distribution and including time distribution information. The problem of determination of site and setup uncertainty and repeatability is also discussed, observing on one hand the lack of clear indications in standards and, on the other hand, the non-ideality and intrinsic variability of measurement conditions (e.g., rolling stock operating conditions, synchronization issues, and electric arc intermittence).

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Potential deployment of offshore bottom pressure gauges and adoption of data assimilation for tsunami warning system in the western Mediterranean Sea

Geoscience Letters ◽

10.1186/s40562-019-0149-8 ◽

2019 ◽

Vol 6 (1) ◽

Cited By ~ 4

Author(s):

Mohammad Heidarzadeh ◽

Yuchen Wang ◽

Kenji Satake ◽

Iyan E. Mulia

Keyword(s):

Data Assimilation ◽

Warning System ◽

Western Mediterranean ◽

Tsunami Warning ◽

Sensitivity Analyses ◽

Bottom Pressure ◽

Tsunami Warning System ◽

Earthquake Scenarios ◽

The North ◽

Western Mediterranean Basin

AbstractWestern Mediterranean Basin (WMB) is among tsunamigenic zones with numerous historical records of tsunami damage and deaths. Most recently, a moderate tsunami on 21 May 2003 offshore Algeria, North Africa, was a fresh call for strengthening tsunami warning capabilities in this enclosed water basin. Here, we propose to deploy offshore bottom pressure gauges (OBPGs) and to adopt the framework of a tsunami data assimilation (TDA) approach for providing timely tsunami forecasts. We demonstrate the potential enhancement of the tsunami warning system through the case study of the 2003 Algeria tsunami. Four scenarios of OBPG arrangements involving 10, 5, 3 and 2 gauges are considered. The offshore gauges are located at distances of 120–300 km from the North African coast. The warning lead times are 20, 30, 48 and 55 min for four points of interest considered in this study: Ibiza, Palma, Sant Antoni and Barcelona, respectively. The forecast accuracies are in the range of 69–85% for the four OBPG scenarios revealing acceptable accuracies for tsunami warnings. We conclude that installation of OBPGs in the WMB can be helpful for providing successful and timely tsunami forecasts. We note that the OBPG scenarios proposed in this study are applicable only for the case of the 2003 Algeria tsunami. Further studies including sensitivity analyses (e.g., number of OBPG stations; earthquake magnitude, strike, epicenter) are required in order to determine OBPG arrangements that could be useful for various earthquake scenarios in the WMB.

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Safe option-critic: learning safety in the option-critic architecture

The Knowledge Engineering Review ◽

10.1017/s0269888921000035 ◽

2021 ◽

Vol 36 ◽

Author(s):

Arushi Jain ◽

Khimya Khetarpal ◽

Doina Precup

Keyword(s):

Model Uncertainty ◽

Gradient Algorithm ◽

Intrinsic Variability ◽

Expected Return ◽

Practical Applications ◽

Hierarchical Reinforcement Learning ◽

Continuous State ◽

End Conditions ◽

Policy Gradient ◽

High Uncertainty

Abstract Designing hierarchical reinforcement learning algorithms that exhibit safe behaviour is not only vital for practical applications but also facilitates a better understanding of an agent’s decisions. We tackle this problem in the options framework (Sutton, Precup & Singh, 1999), a particular way to specify temporally abstract actions which allow an agent to use sub-policies with start and end conditions. We consider a behaviour as safe that avoids regions of state space with high uncertainty in the outcomes of actions. We propose an optimization objective that learns safe options by encouraging the agent to visit states with higher behavioural consistency. The proposed objective results in a trade-off between maximizing the standard expected return and minimizing the effect of model uncertainty in the return. We propose a policy gradient algorithm to optimize the constrained objective function. We examine the quantitative and qualitative behaviours of the proposed approach in a tabular grid world, continuous-state puddle world, and three games from the Arcade Learning Environment: Ms. Pacman, Amidar, and Q*Bert. Our approach achieves a reduction in the variance of return, boosts performance in environments with intrinsic variability in the reward structure, and compares favourably both with primitive actions and with risk-neutral options.

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The molecular identity of the characean OH− transporter: a candidate related to the SLC4 family of animal pH regulators

PROTOPLASMA ◽

10.1007/s00709-021-01677-3 ◽

2021 ◽

Author(s):

Bianca N. Quade ◽

Mark D. Parker ◽

Marion C. Hoepflinger ◽

Shaunna Phipps ◽

Mary A. Bisson ◽

...

Keyword(s):

Inorganic Carbon ◽

Membrane Conductance ◽

Resting Potential ◽

Large Scatter ◽

Intrinsic Variability ◽

Molecular Identity ◽

Ph Banding ◽

Chara Australis ◽

Ph Increase ◽

External Ph

AbstractCharaceae are closely related to the ancient algal ancestors of all land plants. The long characean cells display a pH banding pattern to facilitate inorganic carbon import in the acid zones for photosynthetic efficiency. The excess OH−, generated in the cytoplasm after CO2 is taken into the chloroplasts, is disposed of in the alkaline band. To identify the transporter responsible, we searched the Chara australis transcriptome for homologues of mouse Slc4a11, which functions as OH−/H+ transporter. We found a single Slc4-like sequence CL5060.2 (named CaSLOT). When CaSLOT was expressed in Xenopus oocytes, an increase in membrane conductance and hyperpolarization of resting potential difference (PD) was observed with external pH increase to 9.5. These features recall the behavior of Slc4a11 in oocytes and are consistent with the action of a pH-dependent OH−/H+ conductance. The large scatter in the data might reflect intrinsic variability of CaSLOT transporter activation, inefficient expression in the oocyte due to evolutionary distance between ancient algae and frogs, or absence of putative activating factor present in Chara cytoplasm. CaSLOT homologues were found in chlorophyte and charophyte algae, but surprisingly not in related charophytes Zygnematophyceae or Coleochaetophyceae.

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Analysis of Ocean Bottom Pressure Anomalies and Seismic Activities in the MedRidge Zone

Remote Sensing ◽

10.3390/rs13071242 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1242

Author(s):

Hakan S. Kutoglu ◽

Kazimierz Becek

Keyword(s):

Time Series ◽

Mass Change ◽

Ocean Bottom ◽

Bottom Pressure ◽

Vertical Movements ◽

Ocean Bottom Pressure ◽

Continuous Mass ◽

Mediterranean Ridge Accretionary Complex ◽

Gravity Recovery ◽

Periodic Components

The Mediterranean Ridge accretionary complex (MAC) is a product of the convergence of Africa–Europe–Aegean plates. As a result, the region exhibits a continuous mass change (horizontal/vertical movements) that generates earthquakes. Over the last 50 years, approximately 430 earthquakes with M ≥ 5, including 36 M ≥ 6 earthquakes, have been recorded in the region. This study aims to link the ocean bottom deformations manifested through ocean bottom pressure variations with the earthquakes’ time series. To this end, we investigated the time series of the ocean bottom pressure (OBP) anomalies derived from the Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On (GRACE-FO) satellite missions. The OBP time series comprises a decreasing trend in addition to 1.02, 1.52, 4.27, and 10.66-year periodic components, which can be explained by atmosphere, oceans, and hydrosphere (AOH) processes, the Earth’s pole movement, solar activity, and core–mantle coupling. It can be inferred from the results that the OBP anomalies time series/mass change is linked to a rising trend and periods in the earthquakes’ energy time series. Based on this preliminary work, ocean-bottom pressure variation appears to be a promising lead for further research.

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Frequency-Domain Analysis of the Energy Budget in an Idealized Coupled Ocean–Atmosphere Model

Journal of Climate ◽

10.1175/jcli-d-19-0118.1 ◽

2020 ◽

Vol 33 (2) ◽

pp. 707-726 ◽

Cited By ~ 1

Author(s):

Paige E. Martin ◽

Brian K. Arbic ◽

Andrew McC. Hogg ◽

Andrew E. Kiss ◽

James R. Munroe ◽

...

Keyword(s):

Frequency Domain ◽

Time Scales ◽

Energy Budget ◽

Western Boundary Current ◽

Spectral Energy ◽

Western Boundary ◽

Intrinsic Variability ◽

Boundary Current ◽

Ocean Atmosphere ◽

Atmosphere Model

AbstractClimate variability is investigated by identifying the energy sources and sinks in an idealized, coupled, ocean–atmosphere model, tuned to mimic the North Atlantic region. The spectral energy budget is calculated in the frequency domain to determine the processes that either deposit energy into or extract energy from each fluid, over time scales from one day up to 100 years. Nonlinear advection of kinetic energy is found to be the dominant source of low-frequency variability in both the ocean and the atmosphere, albeit in differing layers in each fluid. To understand the spatial patterns of the spectral energy budget, spatial maps of certain terms in the spectral energy budget are plotted, averaged over various frequency bands. These maps reveal three dynamically distinct regions: along the western boundary, the western boundary current separation, and the remainder of the domain. The western boundary current separation is found to be a preferred region to energize oceanic variability across a broad range of time scales (from monthly to decadal), while the western boundary itself acts as the dominant sink of energy in the domain at time scales longer than 50 days. This study paves the way for future work, using the same spectral methods, to address the question of forced versus intrinsic variability in a coupled climate system.

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The Response to Stratospheric Forcing and Its Dependence on the State of the Troposphere

Journal of the Atmospheric Sciences ◽

10.1175/2009jas2937.1 ◽

2009 ◽

Vol 66 (7) ◽

pp. 2107-2115 ◽

Cited By ~ 35

Author(s):

Cegeon J. Chan ◽

R. Alan Plumb

Keyword(s):

Time Scale ◽

Equilibrium Temperature ◽

Intrinsic Variability ◽

Winter Solstice ◽

Fluctuation Dissipation ◽

Fluctuation Dissipation Theorem ◽

Order Of Magnitude ◽

Leading Mode ◽

Set Up ◽

Hemisphere Winter

Abstract In simple GCMs, the time scale associated with the persistence of one particular phase of the model’s leading mode of variability can often be unrealistically large. In a particularly extreme example, the time scale in the Polvani–Kushner model is about an order of magnitude larger than the observed atmosphere. From the fluctuation–dissipation theorem, one implication of these simple models is that responses are exaggerated, since such setups are overly sensitive to any external forcing. Although the model’s equilibrium temperature is set up to represent perpetual Southern Hemisphere winter solstice, it is found that the tropospheric eddy-driven jet has a preference for two distinct regions: the subtropics and midlatitudes. Because of this bimodality, the jet persists in one region for thousands of days before “switching” to another. As a result, the time scale associated with the intrinsic variability is unrealistic. In this paper, the authors systematically vary the model’s tropospheric equilibrium temperature profile, one configuration being identical to that of Polvani and Kushner. Modest changes to the tropospheric state to either side of the parameter space removed the bimodality in the zonal-mean zonal jet’s spatial distribution and significantly reduced the time scale associated with the model’s internal mode. Consequently, the tropospheric response to the same stratospheric forcing is significantly weaker than in the Polvani and Kushner case.

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Near-field tsunami forecasting from cabled ocean bottom pressure data

Journal of Geophysical Research Atmospheres ◽

10.1029/2008jb005988 ◽

2009 ◽

Vol 114 (B6) ◽

Cited By ~ 94

Author(s):

Hiroaki Tsushima ◽

Ryota Hino ◽

Hiromi Fujimoto ◽

Yuichiro Tanioka ◽

Fumihiko Imamura

Keyword(s):

Near Field ◽

Ocean Bottom ◽

Bottom Pressure ◽

Pressure Data ◽

Ocean Bottom Pressure ◽

Tsunami Forecasting

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Analysis Methods of Bottom Pressure for Fractured-Vuggy Reservoir

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.291-294.3449 ◽

2011 ◽

Vol 291-294 ◽

pp. 3449-3453

Author(s):

Bao Hua Chang ◽

Wei Xiong ◽

Shu Sheng Gao

Keyword(s):

Bottom Pressure ◽

Simple Method ◽

Wellhead Pressure ◽

Analysis Methods ◽

Wellbore Pressure

It’s difficult to measure bottom pressure in the fractured-vuggy reservoir, and measuring cost is usually high; In this paper, using the modified Beggs-Brill method, the variety of wellbore pressure has been calculated and analyzed. Results show that the variety of wellhead pressure is consistent with that of bottom pressure, and the variety of wellhead pressure is greater than that of bottom pressure. Thereby a simple method of predicting bottom pressure through wellhead pressure is established. Through example calculation, it’s confirmed that this method has a certain reliability and practicability.

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