bluuebunny/crossref_metadata_2025 huggingface dataset:
Distinct fungal successional trajectories following wildfire between soil horizons in a cold‐temperate forest
Authors: Yang Teng , Tedersoo Leho , Lin Xingwu , Fitzpatrick Matthew C. , Jia Yunsheng , Liu Xu , Ni Yingying , Shi Yu , Lu Pengpeng , Zhu Jianguo , Chu Haiyan
Published: March 2020

Soil fungi represent a major component of below‐ground biodiversity that determines the succession and recovery of forests after disturbance. However, their successional trajectories and driving mechanisms following wildfire remain unclear.

We examined fungal biomass, richness, composition and enzymes across three soil horizons (Oe, A1 and A2) along a near‐complete fire chronosequence (1, 2, 8, 14, 30, 49 and c. 260 yr) in cold‐temperate forests of the Great Khingan Mountains, China. The importance of soil properties, spatial distance and tree composition were also tested.

Ectomycorrhizal fungal richness and β‐glucosidase activity were strongly reduced by burning and significantly increased with ‘time since fire’ in the Oe horizon but not in the mineral horizons. Time since fire and soil C : N ratio were the primary drivers of fungal composition in the Oe and A1/A2 horizons, respectively. Ectomycorrhizal fungal composition was remarkably sensitive to fire history in the Oe horizon, while saprotroph community was strongly affected by time since fire in the deeper soil horizon and this effect emerged 18 years after fire in the A2 horizon.

Our study demonstrates pronounced horizon‐dependent successional trajectories following wildfire and indicates interactive effects of time since fire, soil stoichiometry and spatial distance in the reassembly of below‐ground fungal communities in a cold and fire‐prone region.
Towards a Hybrid Account of Luck
Authors: de Grefte Job
Published: March 2020

The concept of luck is important in various areas of philosophy. In this paper, I argue that two prominent accounts of luck, the modal and the probabilistic account of luck, need to be combined to accommodate the various ways in which luck comes in degrees. I briefly sketch such a hybrid account of luck, distinguish it from two similar accounts recently proposed, and consider some objections.
Trauma and the content of hallucinations and post‐traumatic intrusions in first‐episode psychosis
Authors: Peach Natalie , Alvarez‐Jimenez Mario , Cropper Simon J. , Sun Pamela , Halpin Emma , O’Connell Jessica , Bendall Sarah
Published: March 2020

Objective

Increasing evidence suggests experiences of childhood trauma may be causally related to the development of hallucinations. Cognitive theories of psychosis suggest post‐traumatic intrusions to be a primary mechanism in this relationship. These theories predict that the content of hallucinations will be related to traumatic experiences; however, few studies have investigated this. This study examined the relationship between childhood trauma, the content of hallucinations, and the content of post‐traumatic intrusions in a sample with first‐episode psychosis.

Methods

Sixty‐six young people aged 15–25 experiencing a first episode of psychosis were recruited from an early intervention service. Participants completed assessments of traumatic experiences, hallucination content, and post‐traumatic intrusion content using a systematic coding frame. The coding frame assessed for three types of relationships between traumatic experiences, the content of hallucinations, and the content of post‐traumatic intrusions: direct relationships (hallucination content exactly matching the trauma/intrusion), thematic relationships (hallucinations with the same themes as the trauma/intrusion), and no relationship (hallucination and trauma/intrusion content unrelated).

Results

Of those people who reported trauma and hallucinations (n = 36), 22 of these (61%) experienced post‐traumatic intrusions, and of these, 16 (73%) experienced hallucinations that were directly or thematically related to their post‐traumatic intrusions. Twelve people experienced hallucination content directly related to their trauma, six of whom (50%) also had intrusions relating to the same traumatic event as their hallucinations.

Conclusions

The finding that some people experience hallucinations and post‐traumatic intrusions relating to the same traumatic event supports theories proposing a continuum of memory intrusion fragmentation. These results indicate that early intervention services for young people with psychosis should provide assessment and intervention for trauma and PTSD and should consider the impact of past traumatic events on the content of current hallucinatory experience.

Practitioner points

Trauma and post‐traumatic stress disorder should be assessed in those experiencing a first episode of psychosis. Interventions for trauma should be offered in early intervention for psychosis services.

In a notable proportion of people, hallucination content is related to traumatic experiences.

Clinical assessment and formulation of hallucinations requires consideration of how past traumatic events may be contributing to hallucinatory experience.

It is important for clinicians to have an understanding of the phenomenological differences between hallucinations and post‐traumatic intrusions when conducting clinical assessments with people with comorbid psychosis and PTSD.
Hydraulic acclimation in a Mediterranean oak subjected to permanent throughfall exclusion results in increased stem hydraulic capacitance
Authors: Salomón Roberto L. , Steppe Kathy , Ourcival Jean M. , Villers Selwyn , Rodríguez‐Calcerrada Jesús , Schapman Roderick , Limousin Jean M.
Published: March 2020

Stem water storage capacity and hydraulic capacitance (CS) play a crucial role in tree survival under drought‐stress. To investigate whether CS adjusts to increasing water deficit, variation in stem water content (StWC) was monitored in vivo for 2 years and related to periodical measurements of tree water potential in Mediterranean Quercus ilex trees subjected either to permanent throughfall exclusion (TE) or to control conditions. Seasonal reductions in StWC were larger in TE trees relative to control ones, resulting in greater seasonal CS (154 and 80 kg m−3 MPa−1, respectively), but only during the first phase of the desorption curve, when predawn water potential was above −1.1 MPa. Below this point, CS decreased substantially and did not differ between treatments (<20 kg m−3 MPa−1). The allometric relationship between tree diameter and sapwood area, measured via electrical resistivity tomography, was not affected by TE. Our results suggest that (a) CS response to water deficit in the drought‐tolerant Q. ilex might be more important to optimize carbon gain during well‐hydrated periods than to prevent drought‐induced embolism formation during severe drought stress, and (b) enhanced CS during early summer does not result from proportional increases in sapwood volume, but mostly from increased elastic water.
Sally–Anne test and regional cerebral blood flow in Alzheimer's disease dementia
Authors: Takenoshita Shintaro , Hayashi Satoshi , Shinya Takayoshi , Miki Tomoko , Yokota Osamu , Maki Yohko , Hattori Hideyuki , Yamada Norihito , Terada Seishi
Published: March 2020

Aim

It was recently reported that theory of mind is disturbed in mild Alzheimer's disease dementia (ADD). Some studies have reported reduced scores of ADD patients on false belief tests, even on first‐order false belief tests. However, few studies have pursued the neural substrate of false belief tests in patients with ADD in a real‐world setting.

Methods

Sixty‐three patients with ADD from outpatient units took the Sally–Anne test and underwent brain single‐photon emission computed tomography. Of these patients, 29 answered the Sally–Anne test correctly (successful group) and 34 incorrectly (unsuccessful group). We compared the regional cerebral blood flow between the successful and unsuccessful groups.

Results

A comparison of the two groups showed a significantly lower uptake in the bilateral posterior cingulate gyrus in the unsuccessful group than in the successful group.

Conclusions

The posterior cingulate gyrus is known to be particularly activated when individuals remember personal events and infer the mental states of others. We suppose that memory or mentalization in the posterior cingulate gyrus—or both—is essential for patients with ADD to be able to pass the Sally–Anne test.
Coeval deposition of transgressive and normal regressive stratal packages in a structurally controlled area of the Viking Formation, central Alberta, Canada
Authors: Schultz Sarah K. , MacEachern James A. , Catuneanu Octavian , Dashtgard Shahin E.
Published: March 2020

Variability in accommodation and sedimentation rates within a basin generates significant deviations in the along‐strike stratal stacking patterns of systems tracts. This variability can lead to coeval depositional units that record the juxtaposition of transgressive (retrogradational) and regressive (progradational) stratal stacking patterns. In scenarios where transgressive and regressive units are deposited concurrently, challenges arise when attempting to correlate and place systems tracts into a sequence stratigraphic framework. In these scenarios, the maximum flooding surface records a high level of diachroneity, with the position of the surface variable throughout the stratigraphic column. In this study, Viking Formation (late Albian) deposits in the Western Canada Sedimentary Basin, central Alberta, Canada, preserve significant along‐strike variability of palaeoshorelines that developed in response to autogenic processes as well as allogenic controls that were active during deposition. Specifically, structural reactivation of Precambrian basement structures during Viking deposition led to significant variability in depositional environments along the palaeoshoreline. The incremental basement reactivation of the Precambrian Snowbird Tectonic Zone influenced sedimentation patterns and the creation of anomalous zones of accommodation in localized areas of the basin. Across fault boundaries and within the anomalously thick strata, both progradational and retrogradational stacking patterns occur within broadly contemporaneous deposits, complicating the correlation of stratigraphic units. While the concomitant deposition of transgressive and regressive units has been documented in a number of modern marine analogues, the concept is rarely applied to ancient successions. By identifying along‐strike variabilities in shoreline geometries and incorporating the autogenic and allogenic controls that were active during deposition, a more accurate sequence stratigraphic framework can be proposed.
Improvement of the digital image correlation close to the borders of an object
Authors: Baconnais M. , Réthoré J. , François M.
Published: March 2020

The measurement error of the finite‐element‐based Digital Image Correlation is reduced along the borders of an object by using the precise measurement, obtained by Virtual Image Correlation (VIC). The proposed method is called Virtual and Digital Image Correlation (VDIC). The boundary, identified by the VIC with a subpixel precision, is used firstly to create an adapted mesh and secondly to create a pixel mask. Futhermore, the VDIC also uses the VIC measurement of the boundary in the deformed state as a constraint on the radial displacement field along the border. The optimal values of the parameters of the VDIC are discussed throughout a sensitivity analysis. The compared performances of the constrained and unconstrained VDIC are obtained thanks to a synthetic test of a plate with a hole in tension. Finally, the method is checked on a sample geometry which includes holes and a U‐shaped notch.
Numerical Study of Rotor–Stator Interaction of a Centrifugal Pump at Part Load With Special Emphasis on Unsteady Blade Load
Authors: Casimir Nicolas , Zhu Xiangyuan , Hundshagen Markus , Ludwig Gerhard , Skoda Romuald
Published: March 2020

Three-dimensional (3D) unsteady Reynolds-averaged Navier–Stokes (URANS) flow simulations are conducted to investigate the highly unsteady flow field at part load operation of a centrifugal pump. By the availability of unsteady flow field measurement data in the impeller wake region, a thorough validation of the simulation method is performed. Grid independence of the results is ensured. Unsteady characteristics in terms of head and shaft power as well as transient blade loads are evaluated to assess the unsteady pump performance. Significant mis-loading of the blading is revealed when one blade passes the volute tongue and associated with the strong unsteady and 3D flow field in the impeller-volute tongue region. Negative radial velocity in the tongue region is the origin of a vortex at the blade pressure side and a subsequent pressure drop that leads to even temporally negative blade loading. The results provide a detailed insight in the complex part load flow field that might be utilized for an improved pump design. As a valuable secondary outcome, a comparison of results obtained by two widely used computational fluid dynamics (CFD) codes for pump flow simulation is provided, i.e., the commercial code ansyscfx and the branch foam-extend of the open source software openfoam. It is found that the results of both methods in terms of unsteady characteristics as well as local ensemble-averaged velocity field are consistent.
Effects of Wall Slip on Convective Heat Transfers of Giesekus Fluid in Microannulus
Authors: Moayed Mohseni Mehdi , Tissot Gilles , Badawi Michael
Published: March 2020

Convective heat transfer and effect of nonlinear wall slip are studied analytically in concentric microannulus for viscoelastic fluids obeying the Giesekus constitutive equation. Laminar, thermally, and hydrodynamically fully developed flow is considered. A nonlinear Navier model with nonzero slip critical shear stress is employed for the slip equation at both walls. Critical shear stress will cause three slip flow regimes: no slip condition, slip only at the inner wall, and slip at both walls. Thermal boundary conditions are assumed to be peripherally and axially constant fluxes at the walls. Governing equations are solved to obtain temperature profiles and Nusselt number and effects of slip parameters, elasticity, and Brinkman number are discussed. Two regimes are compared when slip occurs at both walls or only at the inner wall. The results indicate that by increasing slip effect and elasticity, heat transfer between wall and fluid is enhanced, but it decreases by increasing Brinkman number. In the case where the heat flux is dominant in the outer wall, the inner wall Nusselt curve shows a singularity for a critical Brinkman number because at this Brinkman number the bulk temperature will be equal to the wall temperature.
Discussion: “Thermoelastic Interactions in a Slim Strip Due to a Moving Heat Source Under Dual-Phase-Lag Heat Transfer” (Sarkar, N., and Mondal, S., 2019, ASME J. Heat Transfer, 141(12), p. 124501)
Authors: Pantokratoras Asterios
Published: March 2020

Some errors exist in the above paper.
The Effects of Layer-by-Layer Thickness and Fiber Volume Fraction Variation on the Mechanical Performance of a Pressure Vessel
Authors: Özaslan Emre , Yetgin Ali , Acar Bülent , Coşkun Volkan , Olğar Tarık
Published: March 2020

Due to high stiffness/weight ratio, composite materials are widely used in aerospace applications such as motor case of rockets which can be regarded as a pressure vessel. The most commonly used method to manufacture pressure vessels is the wet filament winding. However, the mechanical performance of a filament wound pressure vessel directly depends on the manufacturing process, manufacturing site environmental condition, and material properties of matrix and fiber. The designed pressure vessel may not be manufactured because of the mentioned issues. Therefore, manufacturing of filament wound composite structures are based on manufacturing experience and experiment. In this study, effects of layer-by-layer thickness and fiber volume fraction variation due to manufacturing process on the mechanical performance were investigated for filament wound pressure vessel with unequal dome openings. First, the finite element model was created for designed thickness dimensions and constant material properties for all layers. Then, the model was updated. The updated finite element model considered the thickness of each layer separately and variation of fiber volume fraction between the layers. Effects of the thickness and fiber volume fraction on the stress distribution along the motor axial direction were shown. Also hydrostatic pressurization tests were performed to verify finite element analysis in terms of fiber direction strain through the motor case outer surface. Important aspects of analyzing a filament wound pressure vessel were addressed for designers.
Use of the Discrete Transfer Method for Determination of the Radiation Heat Transfer in a Building Environment
Authors: Ganem Ricardo , Kirkpatrick Allan T. , Burns Patrick
Published: March 2020

In order to evaluate comfort conditions inside a room it is necessary to estimate the mean radiant temperature (Tmrt) distribution on it. The generally accepted method to calculate radiation exchange within non-participating enclosures is the Radiosity Intensity Method (RIM). However it is very difficult to compute mean radiant temperatures with this method. This paper proposes the use of a new version of the Discrete Transfer Method (DTM). The DTM has been used before inside combustion chambers and furnaces but rarely in non-participating enclosures, such as a room. However, the Discrete Transfer Method can be used in these kind of enclosures, as this paper demonstrates, to compute the mean radiant temperature. The types of building enclosures examined are ones with with radiant heating panels, windows, and direct solar gain.
Ground-Coupled Heat and Moisture Transfer From Buildings: Part 1 — Analysis and Modeling
Authors: Deru Michael P. , Kirkpatrick Allan T.
Published: March 2020

Ground-heat transfer is tightly coupled with soil-moisture transfer. The coupling is threefold: heat is transferred by thermal conduction and by moisture transfer; the thermal properties of soil are strong functions of the moisture content; and moisture phase change includes latent heat effects and changes in thermal and hydraulic properties. A heat and moisture transfer model was developed to study the ground-coupled heat and moisture transfer from buildings. The model also includes detailed considerations of the atmospheric boundary conditions, including precipitation. Solutions for the soil temperature distribution are obtained using a finite element procedure. The model compared well with the seasonal variation of measured ground temperatures.
The Salt River Project SunDish Dish-Stirling System
Authors: Mayette Jessica B. , Davenport Roger L. , Forristall Russell E.
Published: March 2020

The SunDish is a solar thermal power system designed to produce utility-grade electricity from concentrated sunlight. The system is based on a reflective solar dish concentrator that concentrates solar energy to a Stirling engine/generator, producing a net output of up to 22kW at 1000 W/sq. m. of insolation (Stine and Diver, 1994). Salt River Project (SRP), Science Applications International Corporation (SAIC), STM Corporation, and the U.S. Department of Energy have cooperated to install and operate a prototype SunDish at the Salt River Pima-Maricopa Indian Community Landfill (SRP-MICL) in Tempe, Arizona. Operational results and experiences are discussed. At the site, methane gas is collected from the landfill and used as fuel in the SunDish to generate electricity when sunlight is not available due to clouds, and at night. Gas operation has presented some challenges, and operational experiences and incidents are discussed. Finally, design changes and system improvements that have resulted from operation of the prototype SunDish are discussed.
A Study of the Performance of a Hybrid Liquid Desiccant Cooling System Using Lithium Chloride
Authors: Mago Pedro , Goswami D. Yogi
Published: March 2020

A hybrid desiccant system using aqueous lithium chloride was studied by simulation, laboratory test, and field tests. This paper presents field test of a hybrid solar liquid desiccant cooling system conducted at a test house at the University of Florida’s Energy Research and Education Park. These tests consisted of operating the air conditioning system at the test house in two configurations: the conventional vapor compression system and the hybrid desiccant system. For each configuration the system was operated in two modes: recirculation, and 100% ventilation air.

Experiments were conduct to study the influence of the air mass flow rate, temperature of the inlet air, temperature of the desiccant, and desiccant mass flow rate on the performance of both system configurations.

Based on the field test results it was found that the hybrid desiccant system improves the air conditioning performance in the field test house by decreasing the outlet humidity and temperature of the air. It was also found that the hybrid desiccant cooling system is more cost effective for the case 100% fresh air ventilation than recirculation.
Simulation of an Air-Cooled Solar-Assisted Absorption Air Conditioning System
Authors: Solari L. H. Alva , González J. E.
Published: March 2020

This paper investigates the technical feasibility of using a compact, air-cooled, solar-assisted, absorption air conditioning system in Puerto Rico and similar regions. Computer simulations were conducted to evaluate the system’s performance when subjected to dynamic cooling loads. Within the computer model, heat and mass balances are conducted on each component of the system, including the solar collectors, thermal storage tank, the air-cooled condenser, and the air-cooled absorber. Guidance on component design and insight into the effects of such operating factors as ambient air temperature were gained from exercising the simulation model. Comparisons are made with an absorption air conditioning system that uses a cooling tower instead of air-cooled components. The particular absorption system of study is one that uses lithium bromide and water as the absorbent and refrigerant, respectively. The heat input to the absorption system generator is provided by an array of flat plate collectors that are coupled to a thermal storage tank. Systems having nominal cooling capacities of 10.5, 14, and 17.5 kW were considered. Useful information about the number of collectors needed, storage tank volume and efficiency of the overall system is presented.
A Method for Measuring the Creep Behavior of Pressurized Polymer Tubing
Authors: Wu Chunhui , Mantell Susan C. , Davidson Jane H.
Published: March 2020

Polymer components have been proposed for use in domestic solar hot water heating systems. A polymer heat exchanger is under development for such systems. For heat transfer considerations, the heat exchanger will be comprised of many thin walled tubes. The heat exchanger must survive 10 years of service at high pressure (1.55 MPa) and high temperature (82°C). A novel method has been developed for evaluating the long term performance (creep) of the polymer tubing. Traditional creep testing, performed with dog bone test specimens can not be applied because the thin walled tubing has anisotropic material properties. Consequently, performance must be evaluated directly on the extruded tubing. The method entails wrapping a Constantan wire around the tube specimen to continuously record the hoop strain. For pressure loading of tubing, this method offers significant improvements over strain gage instrumentation. In this paper, the test method is described, an analysis of the strain transfer between the tubing and wire wrap is presented, and strain data for polypropylene tubing measured with a strain gage and wire wrap are compared. The data show that the wire measurement method can be successfully used for the characterization of long term mechanical behavior of polymer tubes.
The Thermal Penalty of an Immersed Heat Exchanger in Integral Collector Storage System
Authors: Arora Saurabh , Davidson Jane , Burch Jay , Mantell Susan
Published: March 2020

The use of a heat exchanger in solar water heating systems reduces the overall system efficiency. In this paper, we derive a simple “penalty factor” that gives the fractional reduction in thermal efficiency imposed by a heat exchanger immersed in an isothermal integral collector storage (ICS) system. The penalty factor depends only on the effectiveness of the heat exchanger, the capacitance of the hot water delivered, and the product of the loss coefficient and aperture area of the ICS. This factor allows the designer to select an appropriate heat exchanger without extensive simulation or experiments. Application of the penalty factor for a load-side (or on-demand) heat exchanger, which operates intermittently at varying flow rates, is discussed and illustrated through example.
Wind Heat Loss From Corrugated, Transpired Solar Collectors
Authors: Gawlik Keith M. , Kutscher Charles F.
Published: March 2020

Heat transfer from a perforated, sinusoidal plate with suction to air flowing over the plate, perpendicular to the corrugations, has been studied numerically and experimentally. This study used a numerical model, validated by wind tunnel tests and hot wire anemometer/resistance thermometer measurements, to determine the heat loss to the air stream over the plate as a function of wind speed, suction velocity, and plate geometry. Both attached and separated flow regimes were observed, and the criterion for flow attachment was determined to be ReV0,P≥6.93ReU∞,A0.5. Correlations were developed for heat transfer to the air stream for each flow regime. For attached flow, the heat transfer can be represented as Nuatt = Nuflat{1 + 0.81 (A/P)0.5}. For separated flow, the following correlation applies: Nusep = 2.05(A/P)1.40Re1.63
Reducing the Costs of Grid-Connected Photovoltaic Systems
Authors: Dunlop James P. , Farhi Brian N. , Post Harold N. , Szaro Jennifer S. , Ventre Gerard G.
Published: March 2020

This paper presents alternative approaches for reducing the costs of roof-mounted, grid-connected photovoltaic (PV) systems. Six cost reduction approaches are presented, together with examples, data and information from Florida and other states. Finally, the paper identifies these areas on which efforts should be focused to achieve the 2020 cost goals established by the U.S. photovoltaic industry.
Solar Ice-Makers Powered by Photovoltaic Cells in Barbados
Authors: Headley Oliver StC. , Hinds William
Published: March 2020

Since incident solar radiation and cooling demand are in phase for most of the day at Caribbean sites, and between 4 and 7 kWh/m2 of solar energy is available virtually every day, solar cooling makes sense. A solar ice maker with a capacity of 50 lbs (22.7 kg) of ice per day was operated at CERMES, UWI, Barbados, for six months using 1.1kWp of BP Solar photovoltaic (PV) panels. This was a pilot study for a full scale, one-tonne-per-day solar ice maker at the fishing village of Skeete’s Bay on the southeast coast of Barbados at a new fishing complex. The Skeete’s Bay solar PV ice maker system uses 148 BP Solar 275F solar PV modules with a maximum output of 4.75A and 17.0V. These are wired in series-parallel to form an array with a nominal output of 11,100W (48V at 231A). This power is directed into a battery bank of twenty four12V, 200Ah (100hour rate) lead acid batteries. Two Trace SW4048 inverters power two Scotsman model 1200AE-32A flake ice machines, each producing 1170 lbs (531kg) per day and feeding into a common storage bin of 4.1m3.
Design of “SIREC-1” Wire Mesh Open Volumetric Solar Receiver Prototype
Authors: Téllez Félix M. , Romero Manuel , Marcos María J.
Published: March 2020

The paper describes the design and status of development of a new open volumetric air receiver prototype. This receiver design, though developed in two phases, constitutes one deliverable in a Spanish project carried out by CIEMAT, IAER and INABENSA. The project, called SIREC, is partially financed by the European Funds for the Regional Development program (FEDER). The receiver prototype is now in fabrication and will be tested in the Sulzer volumetric receiver test facility at the Plataforma Solar de Almería (PSA) in Spain. Testing is scheduled for April, 2001. The prototype design includes an air return system and modular absorber elements, to facilitate their replacement and reduce manufacturing costs. The absorber is wire mesh. A computer code has been set up to select the mesh size (wire diameter and mesh distance) and number of screens. A sensitivity analysis for a variety of operating conditions has been carried out with this code to guide the absorber design and its testing.
Solar Power Tower (SPT) Design Innovations to Improve Reliability and Performance: Reducing Technical Risk and Cost
Authors: Zavoico Alexis B. , Gould William R. , Kelly Bruce D. , Pastoril Ignacio Grimaldi
Published: March 2020

Solar Two (SII) completed successful operations in the spring of 1999 and demonstrated advanced molten-salt power tower technology. It proved that solar energy could be collected and stored on a large scale. The 10 MWe SII power plant operated over a wide range of conditions and demonstrated that electrical power could be generated and dispatched at night during peak demand periods reliably and cost effectively. The experience gained from designing and operating SII is being applied to the design of the next generation commercial Solar Power Tower, 15 MWe Solar Tres (S III) to be located near Cordoba, Spain. The S III design criteria have been developed incorporating the SII lessons learned and a conceptual design is being prepared. Design innovations impact all SIII system elements and result in:

• Molten-nitrate salt thermal storage capacity for 24 hour a day of full electrical energy production.

• Thermal Storage raises annual plant capacity factor from 20–22% for SII to over 60% for SIII.

• Improved plant availability with a 6% improvement in overall annual plant efficiency.

• Improved receiver thermal efficiency by 3%.

• Significant reductions in capital and operating costs.

This paper provides an overview of the technological innovations in SIII resulting from Solar II experience.
The Role of “Allowable Flux Density” in the Design and Operation of Molten-Salt Solar Central Receivers
Authors: Vant-Hull Lorin L.
Published: March 2020

In the 1980’s, the Utility Study [Hilesland and Harder, 1988] identified the external cylindrical molten-salt-in-tube receiver with a surround heliostat field as the most cost effective and practical design for commercial applications. Such designs typically require 50–1000 MW of design-point thermal power at outlet temperatures around 1050 °F (565 °C). Using computer codes such as RCELL [Lipps and Vant-Hull, 1981] or DELSOL [Kistler, 1987] it is straightforward to design an optical system to meet these requirements, defining the smallest receiver (lower cost and thermal losses) and the most cost effective heliostat field. As the performance of heliostats in the anti-sun locations is better, such fields tend to be biased (in the northern hemisphere) to the north side of the receiver, and produce very high flux densities there; typically 2–5 MW/m2. However, the receiver is typicaly limited to a salt velocity and temperature dependent allowable flux density (AFD) of about 1 MW/m2. Design methods to reduce this peak flux to a nominally acceptable value in a cost effective manner are presented. Residual excess flux events under non-nominal conditions are handled by a real-time processor which selects specific heliostats for removal from track. This same processor is used to preheat the receiver, using a special algorithm to define the required flux density.
EuroTrough Design Issues and Prototype Testing at PSA
Authors: Lüpfert Eckhard , Geyer Michael , Schiel Wolfgang , Esteban Antonio , Osuna Rafael , Zarza Eduardo , Nava Paul
Published: March 2020

A parabolic trough collector has been developed for various applications in the 200–400°C temperature range in solar fields up to the hundreds Megawatts range. The design of a new support structure of the collector included concept studies, wind tunnel measurements, finite elements method (FEM) analyses and resulted in a structure with a central framework element. This torque box design will have lower weight and less deformation of the collector structure than the other designs considered. Therefore it will be possible in future to connect more collector elements on one drive which results in reduced total number of drives and interconnecting pipes, thus reducing the installation cost and thermal losses. In terms of the degree of material usage further weight reduction will be possible. The presented design has a significant potential for cost reduction, the most important goal of the EuroTrough project. The prototype has been set-up and is under testing at PSA (Plataforma Solar de Almería) for its thermal and mechanical properties.
greenius: A New Simulation Environment for Technical and Economical Analysis of Renewable Independent Power Projects
Authors: Quaschning Volker , Ortmanns Winfried , Kistner Rainer , Geyer Michael
Published: March 2020

The use of modern simulation tools when planing renewable independent power projects minimizes the risks of these projects. Simulation tools can also help to find the best project site for a special technology or the best technology for a special site. However, a user-friendly powerful simulation tool that provides detailed technical as well as economical analysis of multiple technology types such as photovoltaics, wind energy and solar thermal power plants did not exist until now.

The new simulation environment greenius offers all these possibilities. The main emphasis when developing this software was on the user-friendly interface and the calculation performance. Some simulation results demonstrate the capabilities of the greenius software.
Development of a Molten-Salt Thermocline Thermal Storage System for Parabolic Trough Plants
Authors: Pacheco James E. , Showalter Steven K. , Kolb William J.
Published: March 2020

Thermal storage improves the dispatchability and marketability of parabolic trough power plants allowing them to produce electricity on demand independent of solar collection. One such thermal storage system, a thermocline, uses a single tank containing a fluid with a thermal gradient running vertically through the tank, where hotter fluid (lower density) is at the top of the tank and colder fluid is at the base of the tank. The thermal gradient separates the two temperature potentials. A low-cost filler material provides the bulk of the thermal capacitance of the thermal storage, prevents convective mixing, and reduces the amount of fluid required. In this paper, development of a thermocline system that uses molten-nitrate salt as the heat transfer fluid is described and compared to a two-tank molten salt system. Results of isothermal and thermal cycling tests on candidate materials and salt safety tests are presented as well as results from a small pilot-scale (2.3 MWh) thermocline.
Solar-Upgrading of Fuels for Generation of Electricity
Authors: Tamme Rainer , Buck Reiner , Epstein Michael , Fisher Uriyel , Sugarmen Chemi
Published: March 2020

This paper presents a novel process comprising solar upgrading of hydrocarbons by steam reforming in solar specific receiver reactors and utilizing the upgraded, hydrogen-rich fuel, in high efficiency conversion systems, such as gas turbines or fuel cells. In comparison to conventionally heated processes, about 30 % of fuel can be saved with respect to the same specific output. Such processes can be used in small scale as a stand-alone system for off-grid markets, as well as in large scale to be operated in connection with conventional combined-cycle plants. The solar reforming process has an intrinsic potential for solar/fossil hybrid operation, as well as a capability of solar energy storage to increase the capacity factor.

The complete reforming process will be demonstrated in the SOLASYS project, supported by the European Commission in the JOULE/THERMIE framework. The project has been started in June 1998. The SOLASYS plant is designed for 300 kWel output, it consists of the solar field, the solar reformer and a gas turbine, modified to enable operation both on fossil fuel as well as on the product gas from the solar reformer. The SOLASYS plant will be operated at the experimental solar test facility of the Weizmann Institute of Science, Israel. Start-up of the pilot plant is scheduled for the end of the year 2000.

The midterm goal is to replace fossil fuel feedstock by renewable or non conventional feedstocks in order to increase the share of renewable energy and to establish processes with only minor or no CO2 emissions. Examples are given for solar upgrading of bio-gas from municipal solid waste as well as for upgrading of weak gas resources. With some feedstock pretreatment (removal of sulfur components, adjustment of composition) the product gases after solar reforming can be used for further processing to methanol or other chemical compounds.
Structure-based mechanism of preferential complex formation by apoptosis signal–regulating kinases
Authors: Trevelyan Sarah J. , Brewster Jodi L. , Burgess Abigail E. , Crowther Jennifer M. , Cadell Antonia L. , Parker Benjamin L. , Croucher David R. , Dobson Renwick C. J. , Murphy James M. , Mace Peter D.
Published: March 2020

SAM domains mediate heterotypic and homotypic interactions between ASK family kinases.
A semi-automated method for extracting channels and channel profiles from lidar-derived digital elevation models
Authors: Dong Pinliang , Zhong Ruofei , Xia Jisheng , Tan Shucheng
Published: March 2020

With the advent of digital elevation models (DEMs) and geographic information systems (GIS), several methods have been proposed to extract channels from raster DEMs. Light detection and ranging (lidar) can produce high-resolution DEMs and poses new challenges to existing methods for channel extraction. This paper introduces a semi-automated method for extracting stream channels and channel profiles from high-resolution DEMs using image processing techniques. Based on user-specified approximate locations of start and end points and a few simple parameters, the method implements five automated steps: (1) channel detection using a local minimum value search; (2) channel delineation using Bresenham’s line algorithm and mathematical morphological operation; (3) vectorization; (4) profile generation; and (5) accuracy assessment. The method is implemented as an ArcGIS Python add-in toolbar named Channel Extraction. The application of the toolbar is demonstrated using a lidar-derived DEM in a study area along the San Andreas fault in California, USA. The software and test data are freely available for download (see Supplemental Files1). The demonstrated samples suggest that this new semi-automated method for extracting channels and channel profiles is flexible and user-friendly and can produce accurate results to support geomorphic studies.
Effectiveness of antimicrobial stewardship programmes in neonatology: a systematic review
Authors: Araujo da Silva André Ricardo , Marques Amanda , Di Biase Clara , Faitanin Monique , Murni Indah , Dramowski Angela , Hübner Johannes , Zingg Walter
Published: March 2020

Introduction

Antimicrobial stewardship programmes (ASPs) are recommended to improve antibiotic use in healthcare and reduce antimicrobial resistance (AMR). Our aim was to investigate the effectiveness of ASPs in reducing antibiotic consumption, use of broad-spectrum/restricted antibiotics, antibiotic resistance and healthcare-associated infections (HAIs) in neonates.

Methods

We searched PUBMED, SCIELO, EMBASE and the Cochrane Database (January 2000–April 2019) to identify studies on the effectiveness of ASPs in neonatal wards and/or neonatal intensive care units (NICUs). Outcomes were as follows: reduction of antibiotic consumption overall and of broad-spectrum/target antibiotics, inappropriate antibiotic use, antibiotic resistance and HAIs. ASPs conducted in settings other than acute care hospitals, for children older than 1 month, and ASPs addressing antifungal and antiviral agents, were excluded.

Results

The initial search identified 53 173 titles and abstracts; following the application of filters and inclusion criteria, a total of six publications were included in the final analysis. All studies, of which one was multi-centre study, were published after 2010. Five studies were conducted exclusively in NICUs. Four articles applied multimodal interventions. Reduction of antibiotic consumption overall and/or inappropriate antibiotic use were reported by four articles; reduction of broad-spectrum/targeted antibiotics were reported by four studies; No article evaluated the impact of ASPs on AMR or the incidence of HAI in neonates.

Conclusion

ASPs can be effectively applied in neonatal settings. Limiting the use of broad-spectrum antibiotics and shorting the duration of antibiotic treatment are the most promising approaches. The impact of ASPs on AMR and HAI needs to be evaluated in long-term studies.
Meta-analysis of cardiovascular superiority trials published in theNew England Journal of Medicineto elucidate the concept of superiority margin
Authors: Gamad Nanda , Shafiq Nusrat , Malhotra Samir
Published: March 2020

Objective

To show that overpowered trials claim statistical significance detouring clinical relevance and warrant the need of superiority margin to avoid such misinterpretation.

Design

Selective review of articles published in the New England Journal of Medicine between 1 January 2015 and 31 December 2018 and meta-analysis following Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist.

Eligibility criteria for selecting studies and methods

Published superiority trials evaluating cardiovascular diseases and diabetes mellitus with positive efficacy outcome were eligible. Fixed effects meta-analysis was performed using RevMan V.5.3 to calculate overall effect estimate, pooled HR and it was compared with mean clinically significant difference.

Results

Thirteen eligible trials with 164 721 participants provided the quantitative data for this review. Largely, the primary efficacy endpoint in these trials was the composite of cardiovascular death, non-fatal myocardial infarction, unstable angina requiring rehospitalisation, coronary revascularisation and fatal or non-fatal stroke. The pooled HR was 0.86 (95% CI 0.84 to 0.89, I2=45%) which was lower than the mean clinically significant difference of 0.196 (19.6%, range: 0.09375–0.35) of these studies. There was a wide 95% CI in these studies from 0.56 to 0.99. The upper margin of CI in most of the studies was close to the line of no difference. Absolute risk reduction was small (1.19% to 2.3%) translating to a high median number needed to treat of 63 (range: 43 to 84) over a follow-up duration of 2.95 years.

Conclusions

The results of this meta-analysis indicate that overpowered trials give statistically significant results undermining clinical relevance. To avoid such misuse of current statistical tools, there is a need to derive superiority margin. We hope to generate debate on considering clinically significant difference, used to calculate sample size, as superiority margin.
Vestibular dysfunction due to thalamic metastasis of a corticotropic carcinoma in a dog
Authors: Soler Arias Elber Alberto , Trigo Roberto Hector , Gomez Alvarez Christian Mauricio , Castillo Víctor Alejandro
Published: March 2020

Metastatic pituitary carcinoma and central vestibular syndrome originating in the thalamus are not common disorders in dogs. An 11‐year‐old Maltese dog with pituitary‐dependent hypercortisolism presented signs of central vestibular dysfunction after trilostane treatment. Interestingly, the patient showed remission of vestibular signs after drug withdrawal, but two weeks later, with a new administration of trilostane, these signs reappeared after 48 hours. Postmortem, two neoplasms were found: one in the pituitary gland and the other in the thalamus, both with intense positivity for adrenocorticotropic hormone. Findings were conclusive of a functional corticotropic pituitary carcinoma with thalamic metastasis. Altogether, the vestibular dysfunction in this case was attributed to the effect of the mass in the thalamus, and the remission and reappearance of vestibular signs were associated with the level and the effect of cortisol, which depend on the trilostane therapy. Consequently, thalamic metastasis should be considered as a differential diagnosis in dogs with central vestibular dysfunction.
Antimicrobial prescriptions and adherence to prudent use guidelines for selected canine diseases in Switzerland in 2016
Authors: Lutz Bérénice , Lehner Claudia , Schmitt Kira , Willi Barbara , Schüpbach Gertraud , Mevissen Meike , Peter Ruth , Müntener Cedric , Naegeli Hanspeter , Schuller Simone
Published: March 2020

Background

Antimicrobial resistance is an increasing problem in human and veterinary medicine and is closely linked to the use of antimicrobials. The objective of this study was to describe antimicrobial prescriptions for selected canine diseases in Switzerland during 2016.

Methods

Dogs presented to two university hospitals and 14 private practices for acute diarrhoea (AD; n=371), suspected or confirmed urinary tract infections (UTIs; n=245), respiratory tract infections (RTIs; n=274) or wound infections (WIs; n=175) were included. Clinical history, diagnostic work‐up and antimicrobial prescription (class, dosage and duration) were retrospectively assessed. A justification score was applied to evaluate appropriateness of antimicrobial therapy based on available national and international consensus guidelines.

Results

Antimicrobials were prescribed in 65 per cent of dogs with AD, 88 per cent with UTI, 62 per cent with RTI and 90 per cent with WI. The most prescribed antimicrobial classes (monotherapy and combination therapy) were potentiated aminopenicillins (59 per cent), nitroimidazoles (22 per cent), non‐potentiated aminopenicillins (16 per cent) and fluoroquinolones (13 per cent). Overall, 38 per cent (95 per cent CI 0.35 to 0.41) of the prescriptions were in accordance with consensus guidelines. In dogs with AD, antimicrobial therapy was associated with the presence of haemorrhagic diarrhoea (P<0.05) and complied in 32 per cent with consensus guidelines, which recommend antimicrobial treatment only when sepsis is suspected. A bacterial aetiology was confirmed via culture and/or sediment examination in 36 per cent of dogs with suspected UTI.

Conclusions

Overall, adherence to consensus guidelines was poor both, at university hospitals and private practices. Antimicrobial stewardship measures are therefore needed to improve prudent use.