Deep Learning Denoising Applied to the University of Utah Seismic Stations Network Data

The European Physical Journal C

The production cross-section of a top quark in association with a W boson is measured using proton–proton collisions at . The dataset corresponds to an integrated luminosity of , and was collected in 2012 by the ATLAS detector at the Large Hadron Collider at CERN. The analysis is performed in the single-lepton channel. Events are selected by requiring one isolated lepton (electron or muon) and at least three jets. A neural network is trained to separate the tW signal from the dominant background. The cross-section is extracted from a binned profile maximum-likelihood fit to a two-dimensional discriminant built from the neural-network output and the invariant mass of the hadronically decaying W boson. The measured cross-section is , in good agreement with the Standard Model expectation.

A pouch and an automatic packager for packaging medications into the pouch. One embodiment provides a pouch for containing a plurality of medications. The pouch includes a plurality of discrete compartments, each containing a sub-batch of medications. The pouch also includes serrations at opposite ends of the pouch to separate the pouch from adjacent pouches. The pouch further includes a continuous identifier that spans multiple compartments to give an appearance of one continuous pouch. The plurality of discrete compartments are separated by seals, but not serrations. The continuous identifier includes a border within the opposite ends of the pouch.

This is the Final Technical Report for CRASH-worthy Trustworthy Systems Research and Development CTSRD, SRI Project 19800, sponsored by the Defense Advanced Research Projects Agency DARPA and the Air Force Research Laboratory AFRL, under contract FA8750-10-C-0237 CTSRD as part of the DARPA I2O Clean-slate Resilient Adaptable and Secure Hosts CRASH program. CTSRD was a highly innovative DARPA I2O research project concerned with designing and prototyping new computer hardware-software systems with significantly greater potential trustworthiness than anything at the time. CTSRD was a joint project between the SRI International Computer Science Laboratory and the University of Cambridge Department of Computer Science and Technology. The last few years of the project were devoted primarily to enhancing technology transfer via a close collaboration with Arm Limited.Descriptors:

Journal of high energy physics

A search is presented for the production of the Standard Model Higgs boson in association with a high-energy photon. With a focus on the vector-boson fusion process and the dominant Higgs boson decay into b-quark pairs, the search benefits from a large reduction of multijet background compared to more inclusive searches. Results are reported from the analysis of 132 fb− 1 of pp collision data at= 13 TeV collected with the ATLAS detector at the LHC. The measured Higgs boson signal yield in this final-state signature is 1. 3±1. 0 times the Standard Model prediction. The observed significance of the Higgs boson signal above the background is 1. 3 standard deviations, compared to an expected significance of 1. 0 standard deviations.

Test of the universality of $tau$ and $mu$ lepton couplings in $W$-boson decays from $tar{t}$ events with the ATLAS detector IRIS IRIS Home Sfoglia Macrotipologie & tipologie Autore Titolo Riviste Serie IT Italiano Italiano English English LOGIN 1.IRIS 2.SIARI UNITN 3.03 Contributo in periodico (Part of a journal) 4.03.1 Articolo su rivista (Journal article) Test of the universality of $tau$ and $mu$ lepton couplings in $W$-boson decays from $tar{t}$ events with the ATLAS detector / Aad, Georges; Ricci, Ester; Follega, Francesco Maria; Iuppa, Roberto; Others,. - In: NATURE PHYSICS. - ISSN 1745-2481. - 2020:(2020). Test of the universality of $tau$ and $mu$ lepton couplings in $W$-boson decays from $tar{t}$ events with the ATLAS detector Ricci, Ester;Follega, Francesco Maria;Iuppa, Roberto; 2020-01-01 Scheda breve Scheda completa Scheda completa (DC) Anno di pubblicazione (Date of publication) 2020 …

Physical Review D

A search for the direct production of the supersymmetric partners of τ-leptons (staus) in final states with two hadronically decaying τ-leptons is presented. The analysis uses a dataset of p p collisions corresponding to an integrated luminosity of 139 fb− 1, recorded with the ATLAS detector at the Large Hadron Collider at a center-of-mass energy of 13 TeV. No significant deviation from the expected Standard Model background is observed. Limits are derived in scenarios of direct production of stau pairs with each stau decaying into the stable lightest neutralino and one τ-lepton in simplified models where the two stau mass eigenstates are degenerate. Stau masses from 120 GeV to 390 GeV are excluded at 95% confidence level for a massless lightest neutralino.

The root causes of many security vulnerabilities include a pernicious combination of two problems, often regarded as inescapable aspects of computing. First, the protection mechanisms provided by the mainstream processor architecture and C/C++ language abstractions, dating back to the 1970s and before, provide only coarse-grain virtual-memory-based protection. Second, mainstream system engineering relies almost exclusively on test-and-debug methods, with (at best) prose specifications. These methods have historically sufficed commercially for much of the computer industry, but they fail to prevent large numbers of exploitable bugs, and the security problems that this causes are becoming ever more acute.In this paper we show how more rigorous engineering methods can be applied to the development of a new security-enhanced processor architecture, with its accompanying hardware implementation …

Queue

Overall, there are two broad types of security review: white box and black box. A white-box review is one in which the attackers have nearly full access to information such as code, design documents, and other information that will make it easier for them to design and carry out a successful attack. A black-box review, or test, is one in which the attackers can see the system only in the same way that a normal user or consumer would.

Physical Review D

Combined measurements of Higgs boson production cross sections and branching fractions are presented. The combination is based on the analyses of the Higgs boson decay modes H→ γ γ, Z Z*, W W*, τ τ, b b, μ μ, searches for decays into invisible final states, and on measurements of off-shell Higgs boson production. Up to 79.8 fb− 1 of proton–proton collision data collected at s= 13 TeV with the ATLAS detector are used. Results are presented for the gluon–gluon fusion and vector-boson fusion processes, and for associated production with vector bosons or top-quarks. The global signal strength is determined to be μ= 1.1 1− 0.08+ 0.09. The combined measurement yields an observed (expected) significance for the vector-boson fusion production process of 6.5 σ (5.3 σ). Measurements in kinematic regions defined within the simplified template cross section framework are also shown. The results are interpreted …

Physical review D

A search is presented for pair production of long-lived neutral particles using 33 fb− 1 of s= 13 TeV proton–proton collision data, collected during 2016 by the ATLAS detector at the LHC. This search focuses on a topology in which one long-lived particle decays in the ATLAS inner detector and the other decays in the muon spectrometer. Special techniques are employed to reconstruct the displaced tracks and vertices in the inner detector and in the muon spectrometer. One event is observed that passes the full event selection, which is consistent with the estimated background. Limits are placed on scalar boson propagators with masses from 125 GeV to 1000 GeV decaying into pairs of long-lived hidden-sector scalars with masses from 8 GeV to 400 GeV. The limits placed on several low-mass scalars extend previous exclusion limits in the range of proper lifetimes c τ from 5 cm to 1 m.

A pharmaceutical storage and retrieval system and a method of storing and retrieving pharmaceutical containers from the system. The system includes a pharmaceutical storage and retrieval and a controller operatively coupled to the device to control storage and retrieval functions of the device. The device includes a gantry assembly, a shelving assembly, a user access assembly, and a user authorization system that function in a coordinated manner to carry out the storage and retrieval functions of the device.

Applied and Computational Harmonic Analysis

Input data is high-dimensional while the intrinsic dimension of this data maybe low. Data analysis methods aim to uncover the underlying low dimensional structure imposed by the low dimensional hidden parameters. In general, uncovering these hidden parameters is achieved by utilizing distance metrics that considers the set of attributes as a single monolithic set. However, the transformation of a low dimensional phenomena into measurement of high dimensional observations can distort the distance metric. This distortion can affect the quality of the desired estimated low dimensional geometric structure. In this paper, we propose to utilize the redundancy in the feature domain by analyzing multiple subsets of features that are called views. The proposed methods utilize the consensus between different views to extract valuable geometric information that unifies multiple views about the intrinsic relationships among …

Physical Review D

A search for heavy resonances decaying into a W or Z boson and a Higgs boson produced in proton− proton collisions at the Large Hadron Collider at s= 13 TeV is presented. The analysis utilizes the dominant W→ q q′ or Z→ q q and H→ b b decays with substructure techniques applied to large-radius jets. A sample corresponding to an integrated luminosity of 139 fb− 1 collected with the ATLAS detector is analyzed and no significant excess of data is observed over the background prediction. The results are interpreted in the context of the heavy vector triplet model with spin-1 W′ and Z′ bosons. Upper limits on the cross section are set for resonances with mass between 1.5 and 5.0 TeV, ranging from 6.8 to 0.53 fb for W′→ W H and from 8.7 to 0.53 fb for Z′→ Z H at the 95% confidence level.

Communications of the ACM

How and where software should translate data into a human-readable form.

Communications of the ACM

Dead functions and dead features.

Physics Letters B

Searches for the Higgs boson decays and are performed using data corresponding to an integrated luminosity of 139 fb collected with the ATLAS detector in collisions at TeV at the LHC. No significant signals are observed, in agreement with the Standard Model expectation. For a Higgs boson mass of 125 GeV, the observed (expected) upper limit at the 95% confidence level on the branching fraction is () and on is (). These results represent improvements by factors of about five and six on the previous best limits on and respectively.

Queue

Removing dead code from systems is one of KV's favorite koding pastimes because there is nothing quite like that feeling you get when you get rid of something you know wasn't being used. Code removal is like cleaning house, only sometimes you clean house with a flame thrower, which, honestly, is very satisfying. Since you're using a version-control system (you had better be using a VCS!), it's very easy to remove code without worry. If you ever need the code you removed, you can retrieve it from the VCS at will.

BMC Musculoskeletal Disorders

Background Non-surgical multidisciplinary management is often the first pathway of care for patients with chronic low back pain (LBP). This study explores if patient characteristics recorded at the initial service examination have an association with a poor response to this pathway of care in an advanced practice physiotherapist-led tertiary service. Methods Two hundred and forty nine patients undergoing non-surgical multidisciplinary management for their LBP across 8 tertiary public hospitals in Queensland, Australia participated in this prospective longitudinal study. Generalised linear models (logistic family) examined the relationship between patient characteristics and a poor response at 6 months follow-up using a Global Rating of Change measure. Results Overall 79 of the 178 (44%) patients completing the Global …

The European Physical Journal C

Electron and photon triggers covering transverse energies from 5  to several are essential for the ATLAS experiment to record signals for a wide variety of physics: from Standard Model processes to searches for new phenomena in both proton–proton and heavy-ion collisions. To cope with a fourfold increase of peak LHC luminosity from 2015 to 2018 (Run 2), to , and a similar increase in the number of interactions per beam-crossing to about 60, trigger algorithms and selections were optimised to control the rates while retaining a high efficiency for physics analyses. For proton–proton collisions, the single-electron trigger efficiency relative to a single-electron offline selection is at least 75% for an offline electron of 31 , and rises to 96% at 60 ; the trigger efficiency of a 25  leg of the primary diphoton trigger relative to a tight offline photon selection is more than 96% for an offline photon of …

AGU Fall Meeting 2020

Snow depth spatial variability is a function of interactions among static variables, such as terrain, vegetation, and soil properties and dynamic meteorological variables, such as wind speed and direction, solar radiation, and soil moisture that occur over a range of spatial scales. Unpiloted Aerial System (UAS) lidar allows for the ability to map high spatiotemporal resolution snow depth observations at watershed scales with a high degree of vertical accuracy. Using modest cost, commercially available components, UAS lidar surveys were used to map snow depth and vegetation with high vertical and horizontal resolution in open terrain and mixed coniferous and deciduous forests at the University of New Hampshire's Thompson Farm Research Observatory, New Hampshire, United States. Despite the shallow, ephemeral snowpack, snow depth exhibited coherent spatial patterns. This spatial structure was analyzed …

AGU Fall Meeting 2020

Episodes of slow uplift and subsidence of the ground, called bradyseism, characterize the recent dynamics of the Campi Flegrei caldera (Italy). In the last decades two major bradyseismic crises occurred, in 1969/1972 and in 1982/1984, with a ground uplift of 1.70 m and 1.85 m, respectively. Thousands of earthquakes, with a maximum magnitude of 4.2, caused the partial evacuation of the town of Pozzuoli in October 1983. This was followed by about 20 years of overall subsidence, about 1 m in total, until 2005. After 2005 the Campi Flegrei caldera has been rising again, with a slower rate, and a total maximum vertical displacement in the central area of ca. 70 cm. The two signals of ground deformation and background seismicity have been found to share similar accelerating trends. The failure forecast method can provide a first assessment of failure time on present‐day unrest signals at Campi Flegrei caldera (Italy) based on the monitoring data collected in [2011, 2020] and under the assumption to extrapolate such a trend into the future. In this study, we apply a probabilistic approach that enhances the well‐established method by incorporating stochastic perturbations in the linearized equations. The stochastic formulation enables the processing of decade‐long time windows of data, including the effects of variable dynamics that characterize the unrest. We provide temporal forecasts with uncertainty quantification, potentially indicative of eruption dates. The basis of the failure forecast method is a fundamental law for failing materials: ẇ^-α ẅ = A, where ẇ is the rate of the precursor signal, and α, A are model parameters that we fit on the …

AGU Fall Meeting 2020

• The Apollo Heat Flow Experiments were both within areas dominated by Thorium-rich crust. How the PKT came to exist depends on internal structure.• Determining the physical and thermal structure of the lunar core and deep interior is critical for understanding the Moon's formation. Geophysical data reveal the evolution of the lunar dynamo, by which the Moon may have generated and maintained its own magnetic field. They also provide context for thermal emission and volcanism studies.

AGU Fall Meeting 2020

Snow depth spatial variability is a function of interactions among static variables, such as terrain, vegetation, and soil properties and dynamic meteorological variables, such as wind speed and direction, solar radiation, and soil moisture that occur over a range of spatial scales. Unpiloted Aerial System (UAS) lidar allows for the ability to map high spatiotemporal resolution snow depth observations at watershed scales with a high degree of vertical accuracy. Using modest cost, commercially available components, UAS lidar surveys were used to map snow depth and vegetation with high vertical and horizontal resolution in open terrain and mixed coniferous and deciduous forests at the University of New Hampshire's Thompson Farm Research Observatory, New Hampshire, United States. Despite the shallow, ephemeral snowpack, snow depth exhibited coherent spatial patterns. This spatial structure was analyzed …

AGU Fall Meeting 2020

Snow depth spatial variability is a function of interactions among static variables, such as terrain, vegetation, and soil properties and dynamic meteorological variables, such as wind speed and direction, solar radiation, and soil moisture that occur over a range of spatial scales. Unpiloted Aerial System (UAS) lidar allows for the ability to map high spatiotemporal resolution snow depth observations at watershed scales with a high degree of vertical accuracy. Using modest cost, commercially available components, UAS lidar surveys were used to map snow depth and vegetation with high vertical and horizontal resolution in open terrain and mixed coniferous and deciduous forests at the University of New Hampshire's Thompson Farm Research Observatory, New Hampshire, United States. Despite the shallow, ephemeral snowpack, snow depth exhibited coherent spatial patterns. This spatial structure was analyzed …

AGU Fall Meeting 2020

• The Apollo Heat Flow Experiments were both within areas dominated by Thorium-rich crust. How the PKT came to exist depends on internal structure.• Determining the physical and thermal structure of the lunar core and deep interior is critical for understanding the Moon's formation. Geophysical data reveal the evolution of the lunar dynamo, by which the Moon may have generated and maintained its own magnetic field. They also provide context for thermal emission and volcanism studies.

AGU Fall Meeting 2020

• The Apollo Heat Flow Experiments were both within areas dominated by Thorium-rich crust. How the PKT came to exist depends on internal structure.• Determining the physical and thermal structure of the lunar core and deep interior is critical for understanding the Moon's formation. Geophysical data reveal the evolution of the lunar dynamo, by which the Moon may have generated and maintained its own magnetic field. They also provide context for thermal emission and volcanism studies.

AGU Fall Meeting 2020

Concentrations and the stable isotopic composition of bulk aerosol nitrate (NO3−) were quantified from two GEOTRACES cruises: (a) Alaska–Tahiti (GP15; n = 22) and (b) Peru–Tahiti (GP16; n = 17) to explore the hypothesis that a marine source influences aerosol NO3− in the equatorial Pacific. The δ15N‐NO3− ranged from −14.5‰–0.5‰, with lowest values furthest from the coast, primarily reflecting a shift in sources. The δ18O‐ and Δ17O‐NO3− were both relatively high (65.2‰–85.4‰ and 21.4‰–30.7‰, respectively) and decreased away from continental regions, reflecting a shift in the oxidants that influence the formation of NO3−. Transport modeling and co‐occurrence of low δ15N, δ18O and Δ17O provided evidence for an important influence of marine‐derived alkyl nitrates (RONO2) on aerosol NO3− formation. Based on the Δ17O, we quantified that the contribution of RONO2 to aerosol NO3− can be as …

AGU Fall Meeting 2020

Element-calcium ratios in the skeleton of cold-water coral Desmophyllum dianthus represent potential archives for paleo-reconstruction of several ocean properties including temperature and nutrient concentrations. However, relatively large uncertainties in these proxy calibrations and heterogeneity in the skeletal composition have limited its application to date. We address these issues by analyzing corals cultured under systematically varied seawater conditions (phosphate, barium, temperature, pH, feeding frequency) over a two-year period, and refine the calibration of P/Ca, Ba/Ca, U/Ca, and Li/Mg proxies for seawater phosphate, barium, carbonate ion concentration, and temperature, respectively. Composition of the corals is determined using laser-ablation ICPMS, with robust plasma conditions established using the Normalized Argon Index [1], and proxy element incorporation is evaluated for influences of temperature, pH, and feeding frequency. The aragonite precipitated during the stages of the culturing experiment is identified using fluorescent and geochemical labelling of the skeleton through calcein and lead isotopes, respectively. This approach allows us to resolve monthly and annual increments in these slow growing (1-2mm/year) organisms, and also to evaluate the influence of calcification rate on the composition. We address the issue of heterogeneity by adapting methods for LA-ICPMS imaging to create macroscale images to reveal the full pattern of skeletogenesis and related compositional variability of D. dianthus. Preliminary images suggest that heterogeneity stems from the asymmetric precipitation of aragonite, and from …

AGU Fall Meeting 2020

The joint NASA-ESA-ASI Cassini-Huygens mission [2, 3], which investigated the Saturnian system from 2004 to 2017, provided the first detailed look at its largest moon, Titan. Through 127 targeted flybys of the Cassini orbiter and in situ investigations of the lower atmosphere and surface by the Huygens probe, Titan was revealed for the first time. The mission uncovered surface features such as seas, lakes, dunes, mountains, filled and desiccated river valleys and plains [4-7] that were reminiscent of Earth in some respects but utterly different in others, as well as a dynamic atmosphere laden with organic molecules and replete with multiple layers of haze, clouds and rain [8-11](Fig. 1). Titan provides a unique opportunity to study terrestrial processes in a completely different regime, and to learn about our home planet even as we learn about the solar system.In addition to its astounding successes, Cassini-Huygens left many questions about Titan unanswered (see Section 2). Insights into some of these questions will be provided by NASA’s forthcoming Dragonfly mission, which will land on Titan’s equatorial dune fields and sample the troposphere, surface and low latitude regions. However, Dragonfly will not address many other questions raised by Cassini-Huygens [12], including those related to global-scale geological history, atmospheric seasonal cycle and chemical processes, and origin and evolution of the polar seas, among other things. Furthermore, after Dragonfly only equatorial in situ measurements will

AGU Fall Meeting 2020

The Pliocene epoch (5.3-2.6 million years ago) is the last time Earth experienced atmospheric carbon dioxide levels comparable to present day anthropogenic levels. As such, this time interval is a potential analogue for future, warmer Earth system states. One enigmatic feature of Pliocene climate is a reduced east-west sea surface temperature gradient in the equatorial Pacific (indicative of reduced equatorial upwelling) coinciding with enhanced biological productivity in the eastern equatorial Pacific (indicative of enhanced equatorial upwelling). Here we use boron isotopes to investigate these dynamics and to reconstruct the zonal surface pH gradient across the Pliocene equatorial Pacific. We find a strengthened pH gradient relative to modern (with more acidic conditions in the east than the west) despite a reduced temperature gradient at this time. These findings are in contrast to modern-day dynamics in which …

AGU Fall Meeting 2020

The joint NASA-ESA-ASI Cassini-Huygens mission [2, 3], which investigated the Saturnian system from 2004 to 2017, provided the first detailed look at its largest moon, Titan. Through 127 targeted flybys of the Cassini orbiter and in situ investigations of the lower atmosphere and surface by the Huygens probe, Titan was revealed for the first time. The mission uncovered surface features such as seas, lakes, dunes, mountains, filled and desiccated river valleys and plains [4-7] that were reminiscent of Earth in some respects but utterly different in others, as well as a dynamic atmosphere laden with organic molecules and replete with multiple layers of haze, clouds and rain [8-11](Fig. 1). Titan provides a unique opportunity to study terrestrial processes in a completely different regime, and to learn about our home planet even as we learn about the solar system.In addition to its astounding successes, Cassini-Huygens left many questions about Titan unanswered (see Section 2). Insights into some of these questions will be provided by NASA’s forthcoming Dragonfly mission, which will land on Titan’s equatorial dune fields and sample the troposphere, surface and low latitude regions. However, Dragonfly will not address many other questions raised by Cassini-Huygens [12], including those related to global-scale geological history, atmospheric seasonal cycle and chemical processes, and origin and evolution of the polar seas, among other things. Furthermore, after Dragonfly only equatorial in situ measurements will

AGU Fall Meeting 2020

Given rapid socio-economic growth in the Greater Mekong (GM) region, home to nearly 150 million people from 6 countries, since 2009, hundreds of more dams have been constructed to meet growing and competing water demands such as domestic water supply, food production, hydropower generation, disaster controls, and recreation. Nevertheless, six of the total 13 river basins in the GM are multi-national river basins, making access to existing available data, particularly reservoir data, extremely challenging. Furthermore, multi-reservoir operating policies were not developed until 2014 for domestic seven river basins in Vietnam to ensure dam safety and address competing water demands. This thus raises question how to quantify impacts of dam development and current existing/missing reservoir operating policies for poorly gauged and" geopolitically ungauged" dammed basins in this important region.

AGU Fall Meeting 2020

Social, economic, and environmental implications due to anthropogenic activities are further challenging the sustainability of present methods and frameworks in water resources management. Potential future climate change and socio-economic conditions will pressure the quantity and quality of available water resources in many parts of the world. It is widely acknowledged that there is a need for frameworks that can capture the complex dynamics of society and the environment to help develop more sustainable water resources management strategies. In this research, through the use of storytelling methods, narrative storylines were developed to support a detailed and stakeholder-led description of plausible future scenarios in a watershed. Storylines were used to represent and communicate the interactions (and uncertainty) of the physical aspects of climate and socio-economic drivers in a human-water system …

AGU Fall Meeting 2020

Western boundary current instability gives rise to extraordinary subsurface diatom blooms in the Middle Atlantic Bight slope sea - NASA/ADS Now on home page ads icon ads Enable full ADS view NASA/ADS Western boundary current instability gives rise to extraordinary subsurface diatom blooms in the Middle Atlantic Bight slope sea Oliver, H. ; Zhang, WG ; Smith, WO, Jr. ; Alatalo, P. ; Chappell, D. ; Hirzel, A. ; Packard, G. ; Selden, C. ; Poole, J. ; Sosik, HM ; Stanley, R. ; Zhu, Y. ; McGillicuddy, DJ, Jr. Abstract Publication: AGU Fall Meeting Abstracts Pub Date: December 2020 Bibcode: 2020AGUFMB060.0022O Keywords: 0410 Biodiversity; BIOGEOSCIENCES; 0466 Modeling; BIOGEOSCIENCES; 0480 Remote sensing; BIOGEOSCIENCES; 1922 Forecasting; INFORMATICS No Sources Found © The SAO/NASA Astrophysics Data System adshelp[at]cfa.harvard.edu The ADS is operated by the Smithsonian …

AGU Fall Meeting 2020

Peatlands are one of the largest natural sources of atmospheric methane (CH 4), a potent greenhouse gas; therefore, understanding the impacts of changing environments on peatland CH 4 emissions are critically important for understanding the implications for climate forcing. Climate warming has been found to stimulate peatland CH 4 emissions; however, the underlying mechanisms for this stimulating impact remain understudied. A newly developed terrestrial biosphere model-ELM_SPRUCE-was integrated with observational data obtained from the SPRUCE (Spruce and Peatland Responses Under Changing Environments) project; the model was then applied to understand the CH 4 processes in a northern temperate peatland under a gradient of warming treatments. Warming accelerates all belowground C cycling processes, including mineralization of soil organic matter (SOM) and dissolved organic carbon …

AGU Fall Meeting 2020

Mangroves have been identified as important buffers of coastal storm and wave energy, biological resources, and carbon sinks. Despite their obvious importance, mangroves face a variety of threats, including drowning due to the combined effects of sea level rise (eustatic and relative) and sediment starvation (natural and anthropogenic). The largest mangrove stand in the world, the Sundarbans National Forest in Bangladesh and India, appears relatively healthy in the modern day, as the total area remains nearly constant. This mangrove stand is located on the topset of the Ganges-Brahmaputra-Meghna (GBM) Delta, through which the namesake rivers carry> 1x10^ 9 tons of sediment per year. Future changes to water level, sediment supply, and storm frequency and intensity may upset the delicate balance, threatening the delta health and sustainability. In this study, we examine modern sediment transport and …

AGU Fall Meeting 2020

Hyporheic exchange facilitates many biogeochemical reactions, but it is difficult to predict exactly how water quality will change along hyporheic flowpaths. Water quality is often modeled as a function of hyporheic residence time with the assumption that reaction rates are uniform along hyporheic flowpaths. However, testing this assumption in the field would require sampling multiple locations along a flowpath while also accounting for non-steady boundary conditions. To test the uniformity of reaction rates along simplified hyporheic flowpaths, we monitored spatial patterns in water quality along a 12-m long artificial hyporheic mesocosm system at the HJ Andrews Experimental Forest (Oregon, USA). The mesocosm consists of twelve 1-m aluminum columns packed with local streambed sediment and connected in series, through which fresh streamwater is continually pumped. This system reduces the complexity of …

AGU Fall Meeting 2020

A threshold pressure gradient is needed to trigger fluid flow in low-permeability porous media, causing a nonlinear relationship between the pressure gradient and flow velocity at low-pressure gradient levels (ie, the non-Darcian flow behavior) and thus has important implications in shale oil and gas recovery and high-level nuclear waste disposal in geologic repositories. Despite the importance of non-Darcian flow in many natural and engineering processes, it is still unclear how temperature influences the threshold gradient. To answer this fundamental question, a customized core flooding system designed for high-precision measurements of hydraulic gradients and permeability in swelling bentonite clay was used. The measurements were conducted under steady-state flow conditions using a NaCl solution having 0.1 M ionic strength and clay/sand mixtures. The temperatures range from 20 to 90 and the mass …

AGU Fall Meeting 2020

Accurate monitoring of crop gross primary production (GPP) is critical for designing effective management practices and policies and that can contribute to increasing crop yield. Large uncertainties exist in the current crop GPP estimation because of the assumptions and complexity in models, coarse resolution of climate data, and the indirect link between GPP and the" greenness"(eg NDVI). Recent advances in solar-induced chlorophyll fluorescence (SIF) may provide a better measure of crop GPP, since it directly measures plant photosynthetic activity (ie electron transport rate) and has been shown to be strongly correlated with GPP. New spectral indices such as near-infrared radiance of vegetation (NIR v, Rad) have also been proposed as an accurate proxy of crop GPP. In this study, we aim to improve crop GPP estimation through integrating SIF and spectral indices. By analyzing 12 site-year SIF and …