bluuebunny/crossref_metadata_2025 huggingface dataset:
Anisotropic diffusion of membrane proteins at experimental timescales
Authors: Javanainen Matti , Martinez-Seara Hector , Kelly Christopher V. , Jungwirth Pavel , Fábián Balázs
Published: July 2021

Single-particle tracking (SPT) experiments of lipids and membrane proteins provide a wealth of information about the properties of biomembranes. Careful analysis of SPT trajectories can reveal deviations from ideal Brownian behavior. Among others, this includes confinement effects and anomalous diffusion, which are manifestations of both the nanoscale structure of the underlying membrane and the structure of the diffuser. With the rapid increase in temporal and spatial resolution of experimental methods, a new aspect of the motion of the particle, namely, anisotropic diffusion, might become relevant. This aspect that so far received only little attention is the anisotropy of the diffusive motion and may soon provide an additional proxy to the structure and topology of biomembranes. Unfortunately, the theoretical framework for detecting and interpreting anisotropy effects is currently scattered and incomplete. Here, we provide a computational method to evaluate the degree of anisotropy directly from molecular dynamics simulations and also point out a way to compare the obtained results with those available from SPT experiments. In order to probe the effects of anisotropic diffusion, we performed coarse-grained molecular dynamics simulations of peripheral and integral membrane proteins in flat and curved bilayers. In agreement with the theoretical basis, our computational results indicate that anisotropy can persist up to the rotational relaxation time [τ=(2Dr)−1], after which isotropic diffusion is observed. Moreover, the underlying topology of the membrane bilayer can couple with the geometry of the particle, thus extending the spatiotemporal domain over which this type of motion can be detected.
Potential impacts of shale and tight gas developments on unconfined aquifers – a chemical screening framework
Authors: Doble Rebecca , Mallants Dirk , Aghbelagh Yousef Beiraghdar , Gonzalez Dennis , Davies Phil , Peeters Luk , Crosbie Russell
Published: July 2021

The Geological and Bioregional Assessment Program examines the potential impacts of shale, tight and deep coal gas development on water and the environment. A key part of the project was quantifying the potential for a decline in the water quality of unconfined aquifers due to unintentional chemical release at the soil surface. To assess this hazard, a quantitative analysis of chemical migration pathways was undertaken, which involved the estimation of contaminant attenuation by dilution and dispersion in soil and groundwater. This provided a conservative screening approach to identify areas for further analysis. Attenuation calculations involved one-dimensional advection-dispersion (AD) simulations through the unsaturated zone, and three-dimensional AD solute transport within the surficial aquifers. Dilution factor (DF) relationships for the combined effect of attenuation in the unsaturated and saturated zone were used to construct spatial maps of the potential for impact on aquifer properties after accidental chemical spills. A higher DF (therefore lower consequence of the surface contamination) was associated with deeper unsaturated zones characterized by heavier soils near the surface, and lower ground water velocities due to lower hydraulic conductivity and/or hydraulic gradient in the saturated zone. The framework was applied across the Cooper Basin and Beetaloo Sub-basin and resulted in two types of maps. The first identified areas being more susceptible to contamination if soil remediation does not occur within a 10-year period. The second map shows the spatially variable combined DFs for a ground water receptor, which may be used to develop site-specific management plans and mitigation measures.
Geochemical evidence for a new Triassic petroleum system on the western margin of Australia
Authors: Grosjean Emmanuelle , Edwards Dianne S. , Rollet Nadege , Boreham Christopher J. , Nguyen Duy , Buckler Tamara
Published: July 2021

The unexpected discovery of oil in Triassic sedimentary rocks of the Phoenix South 1 well on Australia’s North West Shelf (NWS) has catalysed exploration interest in pre-Jurassic plays in the region. Subsequent neighbouring wells Roc 1–2, Phoenix South 2–3 and Dorado 1–3 drilled between 2015 and 2019 penetrated gas and/or oil columns, with the Dorado field containing one of the largest oil resources found in Australia in three decades. This study aims to understand the source of the oils and gases of the greater Phoenix area, Bedout Sub-basin using a multiparameter geochemical approach. Isotopic analyses combined with biomarker data confirm that these fluids represent a new Triassic petroleum system on the NWS unrelated to the Lower Triassic Hovea Member petroleum system of the Perth Basin. The Bedout Sub-basin fluids were generated from source rocks deposited in paralic environments with mixed type II/III kerogen, with lagoonal organofacies exhibiting excellent liquids potential. The Roc 1–2 gases and the Phoenix South 1 oil are likely sourced proximally by Lower–Middle Triassic TR10–TR15 sequences. Loss of gas within the Phoenix South 1 fluid due to potential trap breach has resulted in the formation of in-place oil. These discoveries are testament to new hydrocarbon plays within the Lower–Middle Triassic succession on the NWS.
Geological and Bioregional Assessments: a program to encourage industry development and improve regulatory efficiency while maintaining the highest possible environmental standards
Authors: Stacey Andrew , Bouma Mitchell , Turner Emily , Baskys Mitchell
Published: July 2021

The Australian Government’s $35.4 million Geological and Bioregional Assessment (GBA) Program provides independent scientific information and baseline data to governments, the community and regional industries on the potential impacts of shale, tight and deep coal gas development on water and the environment. The program aims to encourage industry development and growth by improving the understanding of upstream operations and their potential impacts to drive regulatory efficiency while maintaining the highest environmental standards. The GBA program comprises a series of independent scientific studies undertaken by CSIRO and Geoscience Australia, supported by the Bureau of Meteorology and managed by the Department of Agriculture, Water and the Environment. The program was conducted in three stages and focuses on where industry is currently exploring, conducting assessments across three regions; the Cooper Basin, Beetaloo Sub-basin and the Isa Superbasin, each with potential to supply gas to the East Coast Gas Market. The GBA program brings together a range of disciplines to collect, aggregate and analyse environmental baseline data to conceptualise the geologic, hydrologic, ecologic and anthropogenic features of these regions. This robust ‘conceptual’ understanding of the regions combined with rigorous hazard identification enables the program to prioritise potential impacts on water and the environment, improving regulatory efficiency by focusing regulators towards managing those activities where the potential impacts can’t be avoided. Additional papers and presentations from our partners in the GBA program tell the story of how the Program was developed and delivered. The Program leaves a legacy of publicly available baseline data, information and assessment tools that will make regulation of the industry more efficient in the regions assessed.
Geological and Bioregional Assessments: a tale of two basins
Authors: Huddlestone-Holmes Cameron R. , Holland Kate , Peeters Luk J. M.
Published: July 2021

The Australian Government’s $35.4 million Geological and Bioregional Assessment (GBA) Program is assessing the potential impacts of shale, tight and deep coal gas development on water and the environment in the Beetaloo, Isa and Cooper GBA regions. This paper compares the outcomes of impact assessments for the Beetaloo and Cooper GBA regions, highlighting the role that local geology, hydrogeology, ecology and regulatory regimes play when assessing potential impacts of unconventional gas development. Unconventional gas development activities between basins are broadly consistent, involving drilling, stimulation of the reservoir (typically through hydraulic fracturing), production and processing of hydrocarbons, export to market and decommissioning and rehabilitation. The characteristics of these activities and their potential impacts are strongly influenced by local factors including the geology, environment, industry practices and regulatory regimes. While subsurface impacts associated with hydraulic fracturing and well integrity are considered unlikely in both regions, regional geology means there is greater stratigraphic separation between target resources and overlying aquifers in the Beetaloo Sub-basin than in the Cooper Basin. Local ecological conditions and species influence the nature of potential impacts on protected matters in the two basins, which are mostly associated with surface disturbance and spills or accidental release of fluids. A key similarity between the two regions is the broadly consistent regulation and management of potential impacts in the two basins. Preliminary results of the causal network analysis indicate that mitigation measures are available for all pathways in which unconventional gas resource development activities may have the potential to impact on endpoints.
Real time emissions monitoring: the foundation of a blockchain enabled carbon economy
Authors: Nielsen Preben , Johnston Shaun , Black Philip
Published: July 2021

With 49% of the world’s gross domestic product under net zero goals, the global community is changing in how it treats emissions and carbon releases, with shareholders, stakeholders and investors demanding transparency on current performance and strategies to reduce or offset emissions. High frequency, reliable data empowers an organisation to strategically optimise and track emissions to reach committed goals from the asset level to the board room and across direct, indirect and supply chain sources (Scope 1, 2 and 3). A carbon footprinting solution, which provides a holistic view of total greenhouse gas emissions, requires a combination of carbon accounting, control system integration, emissions monitoring and greenhouse gas reporting software, to deliver an automated, reliable and verifiable real-time emissions/carbon reporting solution. This solution is also critical in providing managed data which can be utilised in the carbon economy and when combined with a blockchain platform, results in a holistic data transfer chain for emissions reporting which is secure, transparent and trusted throughout industry and government. The role of comprehensive, connected environmental monitoring will be explored in the role of effective emissions offset and carbon trading economies with blockchain supported technologies being presented as an enabling aspect of the overall solution. Smart contracts embedded within a blockchain solution could automate trading mechanisms however require quality emissions monitoring data as a foundation for successful implementation. The role of quality emissions monitoring and governance in this process will be presented together with implications for industry and government for the carbon economy.
Effective engagement on process safety fundamentals in challenging times
Authors: Cary Olivia K. , Netscher Nick
Published: July 2021

Esso Australia Resources Pty Ltd (EAPL) and BHP Billiton Petroleum (Bass Strait) Pty Ltd own a range of offshore and onshore hydrocarbon production facilities, which have been operated by EAPL for over 50 years. Over this time, EAPL has lived a rich history of process safety experiences, and developed a range of processes and systems to manage process safety risks. Despite technical system refinement and advances across industry we continue to experience process safety events, and manage risks with plant both at the start and end of its lifecycle. Many of our major hazards are inherent to our operations, and do not become lower risk with lower product price or field activity levels. It is therefore critical that we maintain a laser focus on managing process safety risks during this time of unprecedented change, and find impactful opportunities to engage with operations, maintenance and technical teams on their role in process safety. To this end, EAPL have commenced a journey of scenario based process safety management and applying it to our most significant risks. The outcome has been a step change in process safety literacy across our business, an increased awareness of safe operating conditions and a workforce engaged in managing safeguard health. This study shares how a scenario based approach can leverage a traditional safety case and safety management system approach and make process safety personal:
Simplifying communication of higher risks and the equipment and processes that keep us safe
Clarifying safeguard ownership and responsibilities for safeguard health management
Embedding safeguard health management in routine operations and maintenance tasks
Strengthening critical safeguards which mostly depend on human performance to be effective
Sediment provenance analysis of the Permian from the Perth Basin using an automated Raman heavy mineral technique
Authors: Munday Stuart , Forbes Anne , Fairey Brenton , Hennig-Breitfeld Juliane , Breitfeld Tim , Hicks Tim , Sheehan Jordan , Kocijan Bow
Published: July 2021

The Early Permian in the onshore Perth Basin has experienced several significant discoveries in the last 8 years. Beginning with the play-opening Waitsia discovery (AWE), this was followed more recently by the Beharra Springs Deep (Beach Energy) and West Erregulla (Strike) discoveries. In addition, Late Permian sands (Dongara and Wagina sandstones) have long been recognised as excellent reservoirs in the basin. This study attempts to better understand the provenance of the Early and Late Permian sediments using automated Raman spectroscopy as a tool to identify variations in heavy mineral assemblages. Automated Raman spectroscopy analysis of heavy minerals minimises operator bias inherent in more traditional optical heavy mineral analyses. These data are integrated with publicly available chemostratigraphy data to enable a better understanding of sediment provenance variations with stratigraphy. In addition, publicly available detrital zircon geochronological data are incorporated to help further understand sediment sources. A transect of wells is investigated, from Arrowsmith-1 in the southernmost extent to Depot Hill-1 and Mt Horner-1 in the north. While the elemental (chemostratigraphy) data suggest some changes in sediment provenance through the Permian of the Perth Basin, the Raman heavy mineral data confirm a number of sediment provenance changes both at key formational boundaries (e.g. top Kingia sandstone) and complex sediment provenance variation within reservoir sandstone units. These results are integrated to demonstrate how sediment provenance holds the key to understanding controls on variable reservoir quality as well as understanding the early infill in this basin.
Importance of Australia's offshore oil and gas infrastructure for fish
Authors: McLean D. , Bond T. , Harvey E. S. , Ierodiaconou D. , Cure K. , Taylor M. , Whitmarsh S. , Sih T. , Macreadie P. I.
Published: July 2021

An assessment to remove, partially remove, leave in situ or repurpose oil and gas infrastructure at end of field life can be more robust if it uses rigorous, relevant and accurate data. We used industry remotely operated vehicle (ROV) video, specialised high-definition stereo-video systems and partnered with industry to enhance future ROV campaigns for the collection of scientific data from infrastructure. Data from 17 pipelines and 51 wells were analysed to report on patterns in fish species richness and abundance in Australia’s north, north-west and south-east regions. This represents the largest synthesised data set on marine communities for pipelines and wells, globally. We observed 401 fish species, 350 along pipelines and 113 on well infrastructure. Potential new fish species, critically endangered species, unique behaviours and diverse communities were discovered around pipeline and well infrastructure. Predicting the environmental consequences of different decommissioning options relies on a region-specific understanding of the ecological communities that are associated with these structures. We showcase marine research from around Australia that will inform local decommissioning and contribute to a more comprehensive global understanding of the impact of subsea infrastructure in our oceans.
Resolving lithostratigraphic complexities in the Crayfish Group, Otway Basin using chemostratigraphy
Authors: Bendall Betina , Forbes Anne , Hill Tony
Published: July 2021

The Otway Basin comprises a significant part of the eastern Australian Southern Rift System, a divergent passive continental margin formed during the Cretaceous separation of the Australian and Antarctic continents. Early rifting activity resulted in the development of many half grabens within the Otway Basin, which are largely infilled by sediments of the Casterton Formation and Crayfish Group. Despite over 20 years of exploration and hydrocarbon production from these units however, their lithostratigraphic characterisation and nomenclature remain ambiguous, with structural complexity and prevalent lateral facies changes leading to confusion in their basin-wide correlation. Deposited in a largely non-marine, fluvial/lacustrine environment, repeating cycles of sandstones and shales of the Crayfish Group can be difficult to resolve using petrology, palynology and wireline log data. The use of chemostratigraphy is favoured as an investigative tool in this situation since changes in provenance, lithic composition, facies, weathering and diagenesis are reflected in the mineralogy of the sediments, resulting in variations in their inorganic geochemistry. Uniform sedimentary successions can thus potentially be differentiated into unique sequences and packages based on their characteristic geochemistry, aiding in the resolution of complex structural relationships and facies changes. In this study, we present new inorganic geochemistry data for four key wells in the South Australian (SA) Penola Trough and interpret the geochemistry data consistent with, and building on, the chemostratigraphic schema of Forbes et al. to demonstrate its utility and robustness. We then undertake inter-well wireline log correlations across the SA Penola Trough using the wells with chemostratigraphic data as controls.
Finding net zero: how green LNG can improve the competitiveness of Australian LNG
Authors: Toleman Daniel , Cullen Lucy
Published: July 2021

Liquefied natural gas (LNG) will continue to play a critical role in the global energy mix. Even under sustainable development scenarios, which envisage aggressive emissions reductions, LNG demand grows through 2040. The benefits of gas combustion over coal are clear and well known, but pressure is mounting for LNG players to make their gas even cleaner by reducing emissions and decarbonising portfolios. Asian LNG buyers are increasingly carbon-conscious. Six ‘carbon-neutral’ cargoes and a long-term supply tender have been announced. More are likely to follow as visibility on carbon credentials becomes the norm, potentially leading to greater scrutiny of projects and new price premiums. As a result, Australian LNG operators, many of whom have comparatively large carbon footprints, must begin the journey towards carbon neutrality. Innovation is key, with proposals including the use of batteries, renewable energy and carbon capture and storage. This study will highlight how these solutions can be deployed to improve Australian LNG’s carbon competitiveness. Regulation must advance in parallel with technology. There remains a lack of transparency and standardised emissions measurement across the industry. The definition of carbon-neutral itself is inconsistent, ranging from carbon-neutrality up to the point-of-sale all the way to an ambitious objective to offset full life cycle emissions. But the trend towards greener LNG is here to stay. In a jurisdiction at the forefront of carbon reduction, Australian players have an opportunity to partner with buyers to shape this new, ‘greener’ market. This study will consider what Australian operators must do to maintain competitiveness in a changing world.
Policy roadmap to net zero: the role of gas in decarbonising the National Energy Market
Authors: Byrom Stephanie , Bongers Geoffrey D. , Boston Andy
Published: July 2021

As the National Energy Market (NEM) changes to a more diverse grid with emissions reduction targets, the way we value technologies must also change (Boston et al. 2017). This change in value is fundamental as the future low emissions grid will require careful planning and implementation to guarantee the lowest total system cost is maintained, particularly as a net zero grid will be drastically larger than the current system. This planning must include system strength. The Australian Energy Market Operator Integrated System Plan states that the current market mechanisms cannot facilitate achieving a low emissions grid (Australian Energy Market Operator (AEMO) 2020a). Policy and market mechanisms will need to be designed for this changing system. If net zero is to be met, Modelling of Energy and Grid Services by Red Vector and Gamma Energy technology has shown that this future grid needs to contain:

approximately 100GW of variable renewable energy;
almost 20GW of firm, low emissions generation, such as gas or coal with carbon capture and storage (CCS), bioenergy with CCS and hydroelectric power. If CCS is not available, nuclear power will be required;
more than 10GW of storage, including pumped hydro energy storage and other energy storage technologies and
over 30GW of firm, dispatchable peaking plant, including coal- and gas-fired power generation.

This study sets out the role for gas in a policy road map to net zero for the NEM, harnessing and reforming existing policies, as well as introducing new mechanisms to achieve net zero emissions while retaining a reliable grid at the lowest total system cost.
The CSIRO In-Situ Laboratory: a field laboratory for derisking underground gas storage
Authors: Michael Karsten , Ricard Ludovic , Stalker Linda , Hortle Allison
Published: July 2021

The industry in western Australia has committed to addressing their carbon emissions in response to the governments aspiration of net zero greenhouse gas emissions by 2050. Natural gas will play an important role in the transition to a fully renewable energy market but will require the geological storage of carbon dioxide to limit emissions and enable the production of blue hydrogen. Underground storage of energy in general (e.g. natural gas, hydrogen, compressed air) will be needed increasingly for providing options for temporary storage of energy from renewable resources and for energy export. Storage operations would need to provide adequate monitoring systems in compliance with yet to be defined regulations and to assure the public that potential leakage or induced seismicity could be confidently detected, managed and remediated. The In-Situ Laboratory in the southwest of western Australia was established in 2019 as a research field site to support low emissions technologies development and provides a unique field site for fluid injection experiments in a fault zone and testing of monitoring technologies between 400m depth and the ground surface. The site currently consists of three wells instrumented with fibre optics, pressure, temperature and electric resistivity sensors as well as downhole geophones. A controlled release of CO2 and various water injection tests have demonstrated the ability to detect pressure and temperature effects associated with fluid injection. Future experiments planned at the site will help in improving the sensitivity of monitoring technologies and could contribute to defining adequate monitoring requirements for carbon dioxide, hydrogen and other energy storage operations.
Measurement of gas contents in shale reservoirs – impact of gas density and implications for gas resource estimates
Authors: Ekundayo Jamiu M. , Rezaee Reza , Fan Chunyan
Published: July 2021

Gas shale reservoirs pose unique measurement challenges due to their ultra-low petrophysical properties and complicated pore structures. A small variation in an experimental parameter, under high-pressure conditions, may result in huge discrepancies in gas contents and the resource estimates derived from such data. This study illustrates the impact of the equation of state on the gas content determined for a shale sample. The gas content was determined from laboratory-measured high-pressure methane adsorption isotherms and theoretically described by a hybrid type model. The modelling involved the use of the Dubinin–Radushkevich isotherm to obtain the adsorbed phase density followed by the Langmuir isotherm to describe the resultant absolute adsorptions. Significant variations were observed in measured adsorption isotherms due to the variations in gas densities calculated from different equations of states. The model parameters and the gas in-place volumes estimated from those parameters also varied significantly.
Business environment review 2020
Authors: Molyneux Simon
Published: July 2021

The petroleum (oil, gas and LNG) business environment in 2020 was adverse. Two factors disrupted the foundations of the global oil and gas industry. First, the COVID-19 global pandemic caused an unprecedented reduction of demand that combined with high levels of production resulted in oversupply of oil, gas and LNG. This gap between supply and demand resulted in a collapse in commodity prices, reduced revenues and cancelling or deferral of investment. Second, societal awareness of the impact of climate change on planet Earth increased. Pressure to reduce carbon emissions and a concomitant societal-shift against carbon-emissions intensive petroleum-based forms of energy generation intensified. Many major players in the petroleum industry re-framed their strategies to focus on energy supply in general and in some cases plan to cease their exploration, development and production activities in the coming decades. In Australia, in part global factors manifested in the deferral of investment decisions on three LNG investments. The Australian Government signalled that gas developments would be a critical part of Australia’s post-COVID recovery and that management of abandonment and decommissioning liabilities would be a factor in the approval of transactions leading to a change in ownership. This paper will describe each of the factors faced by the industry in 2020 and frame the issues facing the petroleum industry in 2021 and beyond.
The narrowing of dendrite branches across nodes follows a well-defined scaling law
Authors: Liao Maijia , Liang Xin , Howard Jonathon
Published: July 2021

Significance

To study the systematic variation of dendrite diameters, we established a superresolution method that allows us to resolve dendrite diameters inDrosophilaclass IV dendritic arborization neurons, a model cell for studying branching morphogenesis. Interestingly, the diameters do not follow any of the known scaling laws. We propose a different scaling law that follows from two concepts: Terminal branches have the smallest diameters, whose average is about 230 nm, and there is an incremental increase in cross-sectional area needed to support each additional terminal branch. The law is consistent with the growing dendritic tips making the primary metabolic demand, which is supplied by microtubule-based transport. If the law generalizes to other neurons, it may facilitate segmentation in connectomic studies.
Emergent inequality and business cycles in a simple behavioral macroeconomic model
Authors: Asano Yuki M. , Kolb Jakob J. , Heitzig Jobst , Farmer J. Doyne
Published: July 2021

Significance

Macroeconomic models play an important role in guiding fiscal and monetary policy. At the core of many of these models is the assumption of a single representative, rational agent. We develop a model that loosens these constraints and explicitly models the social dynamics of households embedded in a social network. In some circumstances this leads to endogenously oscillating economic output resembling business cycles, where households spontaneously become rich or poor. Nonetheless, the production of the economy is close to optimal, even though each household acts myopically. This presents an alternative approach to macroeconomics without using rationality assumptions on households.
Of pumpkin spice lattes and hamplanets
Authors: Signorelli Julia
Published: July 2021

The present study establishes what comprises the genre ofventingas opposed torantingand how venting functions within the Reddit community Fat People Stories. In this subreddit, users compose either real or fictional narratives describing encounters with people of size who are perceived to exhibit rude behavior. Given the sensitive nature of these discussions, they are often fraught with negative emotional expression, and individuals seek a variety of outlets to release these emotions and find commiseration and diversion. An analytical corpus of 45,867 words across ten posts and corresponding comment sections was gathered and analyzed usingAskehave and Nielsen’s (2005)two-dimensional genre model and supplemented with discourse analysis of the individual texts. As the study explores how venting unfolds in a digitally mediated environment, insights gained can have implications for how humans sort through negative emotions in face-to-face communication, and, more specifically, for discourse surrounding public health and body weight.
Spectral asymptotics of Laplacians associated with a class of higher-dimensional graph-directed self-similar measures
*
Authors: Ngai Sze-Man , Xie Yuanyuan
Published: July 2021

The spectral dimension of a fractal Laplacian encodes important geometric, analytic, and measure-theoretic information. Unlike standard Laplacians on Euclidean spaces or Riemannian manifolds, the spectral dimension of fractal Laplacians are often non-integral and difficult to compute. The computation is much harder in higher-dimensions. In this paper, we set up a framework for computing the spectral dimension of the Laplacians defined by a class of graph-directed self-similar measures on

R

d

(d ⩾ 2) satisfying the graph open set condition. The main ingredients of this framework include a technique of Naimark and Solomyak and a vector-valued renewal theorem of Lau et al.
Magnetless reflective gyrotropic spatial isolator metasurface
Authors: Lavigne Guillaume , Caloz Christophe
Published: July 2021

We present the concept of a magnetless reflective gyrotropic spatial isolator (RGSI) metasurface. This is a birefringent metasurface that reflects vertically polarized incident waves into a horizontally polarized waves, and absorbs horizontally polarized incident waves, hence providing isolation between the two orthogonal polarization. We first synthesize the metasurface using surface susceptibility-based generalized sheet transition conditions. We then propose a mirror-backed metaparticle implementation of this metasurface, where transistor-loaded resonators provide the desired magnetless nonreciprocal response. Finally, we demonstrate the metasurface by full-wave simulation results. The proposed RGSI metasurface may be used in various electromagnetic applications, and may also serve as a step towards more sophisticated magnetless nonreciprocal metasurface systems.
Box filtering for real-time curvature scale-space computation
Authors: Hennig M , Mertsching B
Published: July 2021

Curvature scale-space (CSS) analysis is an important technique for contour-based object recognition in digital images. To compute the CSS for a given contour, it is systematically convolved (smoothed) with Gaussians with increasing standard deviation. The convolutions are computationally expensive, especially for large and high resolution contours, but can be approximated using box filtering (also known as mean and average filtering). Together with running sums, the convolutions can be accelerated by 2–3 magnitudes without significant loss of precision. Nonetheless, box filtering has not been systematically investigated in connection with CSS computation. In this work, we present a theoretical and experimental analysis of different box-filtering techniques in this context and conclude which is the most efficient implementation. Based on this, the CSS of a contour can be computed in real time with high precision.
On the selection of an actuating device for a gas-dynamic drive of an object, performing a flat turning maneuver
Authors: Kondratyev A B
Published: July 2021

This paper contains an analysis of the control efficiency influence on the actuating medium supply amount of the gas-dynamic drive of an object, performing a flat turning maneuver, with two different types of actuating devices; it also defines the required momentum impulses. The required momenta are determined depending on the initial position of the object and the time of its transition to the final position. The influence of the actuating device time constant on the control efficiency has been evaluated, and the value of the relative operation speed, at which the engine time constant does not affect the transition time from the initial state to the final one, has been defined.
Aircraft cockpit information field control methodology
Authors: Neretin E S , Lunev E M , Grigoriev N M , Ivanov A S
Published: July 2021

The work is devoted to the development of a human-machine interface (HMI) of the decision support system for the problem of four-dimensional navigation. As part of the work, the analysis of the functionality of modern flight management systems, which is designed to solve the problem of four-dimensional navigation, was carried out. The problems that arise during flights along the four-dimensional navigation routes are determined, and the insufficiency of the existing functionality of modern flight management systems for solving these problems is substantiated. The paper proposes the functionality of the decision support system as an addition to the functionality of the flight management systems, as well as the organization of the HMI of the decision support system, which provides display of the necessary information for the decision-making process by the crew.
The importance of temporal resolution in modeling deep decarbonization of the electric power sector
Authors: Bistline John E T
Published: July 2021

Power sector decarbonization is a central pillar of economy-wide emissions reductions. However, model complexity, especially temporal resolution, can materially impact power sector decarbonization pathways. Using a detailed electric sector capacity planning and dispatch model, this analysis explores impacts of temporal resolution on electric sector investments and costs and how these outcomes vary under different policy and technology assumptions. Results show that approaches to simplify temporal variability used in many integrated assessment and energy system models may not replicate fundamental relationships for power sector decarbonization or may exhibit large quantitative deviations from more detailed modeling, including abatement costs rising nonlinearly at higher decarbonization levels; variable renewables and batteries being accompanied by additional low-/zero-/negative-emissions resources, especially approaching 100% decarbonization; and carbon removal technologies altering electric sector costs and investments. Representative day approaches can preserve many of these properties with large reductions in computational complexity. Simplified temporal aggregation approaches tend to understate the value of broader technological portfolios, firm low-emitting technologies, wind generation, and energy storage resources and can overstate the value of solar generation. Approximation accuracy also depends on assumptions about technological cost and availability: differences across approaches are smaller when carbon removal is available and when renewables costs are lower. The analysis indicates that higher temporal resolution is increasingly important for policy analysis, electric sector planning, and technology valuation in scenarios with deeper decarbonization and higher variable renewables.
Assessing the impact of climate change on soil erosion in East Africa using a convection-permitting climate model
Authors: Chapman Sarah , Birch Cathryn E , Galdos Marcelo V , Pope Edward , Davie Jemma , Bradshaw Catherine , Eze Samuel , Marsham John H
Published: July 2021

East Africa is highly reliant on agriculture and has high rates of soil erosion which negatively impact agricultural yields. Climate projections suggest that rainfall intensity will increase in East Africa, which is likely to increase soil erosion. Soil erosion estimates require information on rainfall erosivity, which is calculated using sub-daily storm characteristics that are known to be biased in traditional parameterized convection climate models. Convection-permitting climate models, which are run at higher resolution to negate the need for convection parameterization, generally better represent rainfall intensity and frequency. We use a novel convection-permitting pan-Africa regional climate model (CP4A) to estimate rainfall erosivity in Tanzania and Malawi, and compare it to its parameterized counterpart (P25), to determine if there is a benefit to using convection-permitting climate models to look at rainfall erosivity. We use eight year historical and end-of-century (RCP8.5) climate simulations to examine the impact of climate change on soil erosion in Tanzania and Malawi based on rainfall erosivity estimates from CP4A and P25 applied to the Revised Universal Soil Loss Equation. The effectiveness of soil conservation measures was also evaluated. Rainfall erosivity was lower in P25 than in CP4A and was a poorer match to observational storm characteristics, even after bias-correction. These results suggest that parameterized convection regional and global climate models might under-estimate rainfall erosivity, and the associated soil erosion. We found high values of present day erosion in mountainous regions in Tanzania and Malawi in CP4A. Under climate change, areas at high risk of soil erosion expanded due to increases in rainfall intensity in CP4A. Terracing was less effective at reducing soil erosion risk in the future than in the present day, and more extensive soil management may be required to manage soil erosion and reduce the negative impacts of soil erosion on agriculture.
The impact of film thickness on the properties of ZnO/PVA nanocomposite film
Authors: Khan Shaheer Ahmed , Rahman Ataur , Dafa-Alla Ibrahim Fatima Babiker
Published: July 2021

Polymer inorganic nanocomposites are attracting a considerable amount of interest due to their enhanced electrical and optical properties. The inclusion of inorganic nanoparticles into the polymer matrix results in a significant change in the nanocomposite’s properties. With this in mind, we have developed a nanocomposite film based on zinc oxide (ZnO) and polyvinyl alcohol (PVA) using a solution casting method with varying concentrations of ZnO nano powder in the PVA matrix. The ZnO / PVA film surface morphology was observed by the scanning electron microscope (SEM). The micrographs indicate that ZnO nanoparticles in the PVA matrix are homogeneously distributed. XRD results indicated that the crystallinity of the film was influenced by the interaction of ZnO nanoparticles and the PVA main chain. Crystallinity is also affected by the doping of ZnO nanoparticles in the PVA matrix and it increases when the concentration of ZnO is low and then decreases when the excess concentration of ZnO is present in the PVA matrix. The FTIR transmission spectra confirmed that significant interaction took place between the ZnO nanoparticles and the PVA main chain over the wave number range of 400–4000 cm−1. The UV–vis spectra reveal that the increase in concentration of ZnO nanoparticles in the polymer matrix results in the movement of the absorption edge in the direction of higher wavelength or lower energy associated with the blue/green portion of the visible spectrum. A decrease in the optical energy bandgap is observed with the increase in nano ZnO concentration in the matrix. Thickness has a signifcant affect on the properties of the ZnO/PVA nanocomposite and the morphology, particle size, degree of crystallinity and bandgap of the ZnO/PVA nanocomposite samples were influenced by the thickness of the sample. The optimal thickess of 0.03 mm with a weight percentage of 16.6% (ZnO) and 83.3% (PVA matrix) was selected due to its higher bandgap of 4.22 eV, reduced agglomeration/aggregation and smaller ZnO particle size of 14.23 nm in the matrix. The optimal film can be used in photovoltaic research.
Completion pancreatectomy or a pancreas-preserving procedure during relaparotomy for pancreatic fistula after pancreatoduodenectomy: a multicentre cohort study and meta-analysis
Authors: Groen J V , Smits F J , Koole D , Besselink M G , Busch O R , den Dulk M , van Eijck C H J , Groot Koerkamp B , van der Harst E , de Hingh I H , Karsten T M , de Meijer V E , Pranger B K , Molenaar I Q , Bonsing B A , van Santvoort H C , Mieog J S D ,   the Dutch Pancreatic Cancer Group
Published: July 2021

Background

Despite the fact that primary percutaneous catheter drainage has become standard practice, some patients with pancreatic fistula after pancreatoduodenectomy ultimately undergo a relaparotomy. The aim of this study was to compare completion pancreatectomy with a pancreas-preserving procedure in patients undergoing relaparotomy for pancreatic fistula after pancreatoduodenectomy.

Methods

This retrospective cohort study of nine institutions included patients who underwent relaparotomy for pancreatic fistula after pancreatoduodenectomy from 2005–2018. Furthermore, a systematic review and meta-analysis were performed according to the PRISMA guidelines.

Results

From 4877 patients undergoing pancreatoduodenectomy, 786 (16 per cent) developed a pancreatic fistula grade B/C and 162 (3 per cent) underwent a relaparotomy for pancreatic fistula. Of these patients, 36 (22 per cent) underwent a completion pancreatectomy and 126 (78 per cent) a pancreas-preserving procedure. Mortality was higher after completion pancreatectomy (20 (56 per cent) versus 40 patients (32 per cent); P = 0.009), which remained after adjusting for sex, age, BMI, ASA score, previous reintervention, and organ failure in the 24 h before relaparotomy (adjusted odds ratio 2.55, 95 per cent c.i. 1.07 to 6.08). The proportion of additional reinterventions was not different between groups (23 (64 per cent) versus 84 patients (67 per cent); P = 0.756). The meta-analysis including 33 studies evaluating 745 patients, confirmed the association between completion pancreatectomy and mortality (Mantel–Haenszel random-effects model: odds ratio 1.99, 95 per cent c.i. 1.03 to 3.84).

Conclusion

Based on the current data, a pancreas-preserving procedure seems preferable to completion pancreatectomy in patients in whom a relaparotomy is deemed necessary for pancreatic fistula after pancreatoduodenectomy.
Associations between pancreatic expression quantitative traits and risk of pancreatic ductal adenocarcinoma
Authors: Pistoni Laura , Gentiluomo Manuel , Lu Ye , López de Maturana Evangelina , Hlavac Viktor , Vanella Giuseppe , Darvasi Erika , Milanetto Anna Caterina , Oliverius Martin , Vashist Yogesh , Di Leo Milena , Mohelnikova-Duchonova Beatrice , Talar-Wojnarowska Renata , Gheorghe Cristian , Petrone Maria Chiara , Strobel Oliver , Arcidiacono Paolo Giorgio , Vodickova Ludmila , Szentesi Andrea , Capurso Gabriele , Gajdán László , Malleo Giuseppe , Theodoropoulos George E , Basso Daniela , Soucek Pavel , Brenner Hermann , Lawlor Rita T , Morelli Luca , Ivanauskas Audrius ,   PanGenEU Study Investigators, Kauffmann Emanuele Federico , Macauda Angelica , Gazouli Maria , Archibugi Livia , Nentwich Michael , Loveček Martin , Cavestro Giulia Martina , Vodicka Pavel , Landi Stefano , Tavano Francesca , Sperti Cosimo , Hackert Thilo , Kupcinskas Juozas , Pezzilli Raffaele , Andriulli Angelo , Pollina Luca , Kreivenaite Edita , Gioffreda Domenica , Jamroziak Krzysztof , Hegyi Péter , Izbicki Jakob R , Testoni Sabrina Gloria Giulia , Zuppardo Raffaella Alessia , Bozzato Dania , Neoptolemos John P , Malats Núria , Canzian Federico , Campa Daniele
Published: July 2021

Pancreatic ductal adenocarcinoma (PDAC) is among the most lethal cancers. Its poor prognosis is predominantly due to the fact that most patients remain asymptomatic until the disease reaches an advanced stage, alongside the lack of early markers and screening strategies. A better understanding of PDAC risk factors is essential for the identification of groups at high risk in the population. Genome-wide association studies (GWAS) have been a powerful tool for detecting genetic variants associated with complex traits, including pancreatic cancer. By exploiting functional and GWAS data, we investigated the associations between polymorphisms affecting gene function in the pancreas (expression quantitative trait loci, eQTLs) and PDAC risk. In a two-phase approach, we analysed 13 713 PDAC cases and 43 784 controls and identified a genome-wide significant association between the A allele of the rs2035875 polymorphism and increased PDAC risk (P = 7.14 × 10−10). This allele is known to be associated with increased expression in the pancreas of the keratin genes KRT8 and KRT18, whose increased levels have been reported to correlate with various tumour cell characteristics. Additionally, the A allele of the rs789744 variant was associated with decreased risk of developing PDAC (P = 3.56 × 10–6). This single nucleotide polymorphism is situated in the SRGAP1 gene and the A allele is associated with higher expression of the gene, which in turn inactivates the cyclin-dependent protein 42 (CDC42) gene expression, thus decreasing the risk of PDAC. In conclusion, we present here a functional-based novel PDAC risk locus and an additional strong candidate supported by significant associations and plausible biological mechanisms.
COVID-19: a pandemic converged with global tobacco epidemic and widespread vaping—state of the evidence
Authors: Besaratinia Ahmad
Published: July 2021

This review highlights the convergence of three global health challenges at a crossroad where the pandemic of coronavirus disease 2019 (COVID-19) meets the tobacco epidemic and vaping. It begins with an overview of the current knowledge on the biology, pathophysiology and epidemiology of COVID-19. It then presents the state of smoking and vaping during the pandemic by summarizing the published data on prevalence, use patterns, product availability/accessibility, sales records and motivation to quit before and after the start of the pandemic. It highlights the state of evidence on the association of tobacco product use with COVID-19 infection and transmission rates, symptom severity and clinical outcomes. Also discussed are proposed biological mechanisms and behavioral factors that may modulate COVID-19 risk in tobacco product users. Furthermore, competing hypotheses on the protective effect of nicotine against COVID-19 as well as the claimed ‘smokers’ paradox’ are discussed. Considerations and challenges of COVID-19 vaccination in tobacco product users are underscored. Collectively, the present data show an ‘incomplete’ but rapidly shaping picture on the association of tobacco product use and COVID-19 infection, disease course and clinical outcomes. Evidence is also growing on the mechanisms by which tobacco product use may contribute to COVID-19 pathophysiology. Although we await definitive conclusions on the relative risk of COVID-19 infection in tobacco product users, compelling data confirm that many comorbidities associated with/caused by smoking predispose to COVID-19 infection, severe disease and poor prognosis. Additionally, it is becoming increasing clear that should smokers get the disease, they are more likely to have serious health consequences.