Subsequent Burning Research Articles

Fire severity and the legacy of mountain pine beetle outbreak: high-severity fire peaks with mixed live and dead vegetation

Bark beetle outbreaks and wildfires are two of the most prevalent disturbances that influence tree mortality, regeneration, and successional trajectories in western North American forests. Subboreal forests have experienced broad overlaps in these disturbances, and recent wildfires have burned through landscapes with substantial tree mortality from prior outbreaks. This study investigated how fuel conditions associated with mountain pine beetle outbreaks influence the probability of high burn severity (i.e. stand-replacing fire) across a range of fire weather conditions in subboreal forests of central interior British Columbia, Canada. We focused on three large fires that occurred in 2012, 2013, and 2014. We characterized outbreak severity, outbreak-influenced prefire vegetation, and subsequent burn severity using Landsat spectral vegetation indices, high-resolution imagery, and field observations. Substantial portions of the prefire landscape contained mixtures of live and dead vegetation created by variable beetle damage and vegetation response—spatial patterns that are related to, but distinct from, peak outbreak severity. We evaluated drivers—fuels, weather, and topography—of high-severity fire under ‘extreme,’ ‘moderate,’ and ‘benign’ fire weather conditions (i.e. burning conditions) using Boosted Regression Trees. While fire weather was a primary driver in most cases, prefire vegetation was an influential predictor variable across all burning conditions, and the probability of high-severity fire was highest when prefire vegetation was a mixture of tree mortality from bark beetles and live vegetation. Thus, while weather and drought are important drivers of wildfires in subboreal forests, bottom-up drivers of elevation and vegetation, including the fuel legacies of bark beetle outbreaks, are crucial factors influencing high-severity burning. The legacy of recent bark beetle outbreaks will continue for decades on these landscapes, affecting fuel structures, future wildfires, forest dynamics, and the broader social-ecological systems of the region.

A Most Reactive Mixture Analysis of Ozone- and Temperature-Enhanced n-Heptane Droplet Autoignition and Cool Flame Burning in Microgravity

ABSTRACT Numerical simulations are used to study effects of ozone (O3) and thermal enhancement on autoignition and subsequent burning characteristics of isolated n-heptane droplets in microgravity conditions. Particular focus is given to effects of O3 on low temperature combustion, or cool flames. Levels of ambient O3 mole fraction and ambient temperature are varied from 0 to 0.03 and 400 K to 750 K, respectively. A comparison between two low temperature chemistry enhancement strategies – O3 addition and temperature increase – are investigated on an equivalent energy addition basis to evaluate relative effects on combustion characteristics. Results of this study are analyzed using physical and mixture fraction approaches because of unique insights offered by these frameworks. Ignition and ensuing flame propagation are investigated via a most reactive mixture analysis, evaluated using homogeneous reactor simulations of mixture compositions and temperatures surrounding the droplet. Lastly, a Damköhler number analysis is performed to explore oscillatory ignition dynamics.

Second-Entry Burns Reduce Mid-Canopy Fuels and Create Resilient Forest Structure in Yosemite National Park, California

Understanding the patterns and underlying drivers of forest structure is critical for managing landscape processes and multiple resource management. Merging several landscape-scale datasets, including long-term fire histories, airborne LiDAR, and downscaled topo-climatic data, we assessed complex ecological questions regarding the interactions of forest structure, climate, and fire in the Yosemite National Park, a protected area historically dominated by frequent fire and largely free of the impacts of commercial industrial logging. We found that forest structure broadly corresponded with forest types arranged across elevation-driven climatic gradients and that repeated burning shifts forest structure towards conditions that are consistent with increased resilience, biodiversity, and ecosystem health and function. Specifically, across all forest types, tree density and mid-canopy strata cover was significantly reduced compared to overstory canopy and the indices of forest health improved after two fires, but no additional change occurred with subsequent burns. This study provides valuable information for managers who seek to refine prescriptions based on an enhanced understanding of fire-mediated changes in ladder fuels and tree density and those seeking to define the number of treatments needed to mitigate severe fire risk and enhance resiliency to repeated fires. In addition, our study highlights the utility of large-landscape LiDAR acquisitions for supporting fire, forest, and wildlife management prioritization and wildfire risk assessments for numerous valued resources.

The Dynamic Temperate and Boreal Fire and Forest-Ecosystem Simulator (DYNAFFOREST): Development and evaluation

Fire is a dominant disturbance in temperate and boreal biomes, and increasing burned area with climate change may fundamentally alter forests. Improved information about how fire-induced changes to forests may feedback to affect subsequent burning at regional scales could inform forest management and climate-mitigation strategies. However, fire is simplistically represented in Earth System Models, and regional statistical fire models often assume sufficient fuels, contributing to uncertainty in future projections. To address this challenge, we developed the Dynamic Temperate and Boreal Fire and Forest-Ecosystem Simulator (DYNAFFOREST). DYNAFFOREST represents the hierarchical structuring of forests, from individual cohorts to continental extents, making it possible to simulate feedbacks between fire and forests at broad scales over decades to centuries. We parameterized DYNAFFOREST for the western United States of America and benchmarked simulations with observations. DYNAFFOREST recreated patterns of forest cover, structure, and downed fuels, and was capable of capturing average 20th-century fire activity.

<sup>22</sup>Ne(α, n)<sup>25</sup>Mg: The key neutron source in massive stars

<p indent="0mm">The origin of heavy elements from iron to uranium in the universe is an important frontier direction for nuclear astrophysics. It is considered to be one of the 11 greatest unanswered questions of physics in this century. The neutron capture reaction can overcome the Coulomb barrier and is the key way to generate heavy elements in the universe. The average life of free neutrons is only about <sc>15 min.</sc> Therefore, the neutron source is a hot topic for understanding the origin of heavy elements. There are two main neutron sources in the s-process nucleosynthesis, one is the ¹³C(α, n)¹⁶O reaction, the other is the ²²Ne(α, n)²⁵Mg reaction. The ¹³C(α, n)¹⁶O reaction mainly provides neutrons for the s-process nucleosynthesis of small or medium mass stars, and affects the nucleosynthesis of nuclides with the mass numbers from 90 to 209; while the ²²Ne(α, n)²⁵Mg reaction mainly provides neutrons for the s-process nucleosynthesis of massive stars and affects the nucleosynthesis of nuclides with the mass number less than 90. The ²²Ne(α, n)²⁵Mg reaction takes place in the core helium burning phase and the subsequent shell carbon burning phase of massive stars. Due to the difficulty of experiment measurement, the data of the ²²Ne(α, n)²⁵Mg reaction rate is still lacking, which leads to the problem of understanding effective neutron supply in the nucleosynthesis of the heavy elements in massive stars. Limited by cosmic ray backgrounds, a large number of key reactions in hydrostatic nuclear burning phases cannot be accurately measured. Therefore, direct measurement of these reactions has gradually moved from the earth-surface to underground laboratories. The Laboratory for Underground Nuclear Astrophysics (LUNA) experimental platform in Italy is a mature underground nuclear astrophysics laboratory in the world. Since the 1990s, direct measurement of many nuclear reactions has been carried out. Jinping Underground Nuclear Astrophysics Laboratory (JUNA) is a new experimental platform. JUNA is located in the world’s deepest underground laboratory—China JinPing Underground Laboratory (CJPL). JUNA team has successfully developed a <sc>10 mA</sc> low-energy accelerator and experimental terminal, which aims to conduct experimental research on a number of key nuclear reactions in hydrostatic hydrogen and helium burnings of stars in an underground environment with very low background. Since its operation in the underground laboratory at the end of 2020, JUNA has completed the first phase of experimental tasks and successfully studied several key nuclear reactions including the neutron source reaction¹³C(α, n)¹⁶O. In this paper, we review the motivation of the key neutron source ²²Ne(α, n)²⁵Mg in the origin of heavy elements and in the massive stars, the latest research progress of this neutron source and future research plan, especially the underground direct measurement experimental plan. As the key neutron source reaction of the s-process, the ²²Ne(α, n)²⁵Mg reaction is of great significance for understanding the origin of heavy elements in the universe. As the first experiment in the second phase of JUNA, the ²²Ne(α, n)²⁵Mg reaction is expected to achieve world-class research results and provides the crucial nuclear input for understanding the nucleosynthesis in weak s-process.

Stages and time-scales of ignition and burning of live fuels for different convective heat fluxes

Wildland fires impact ecosystems and communities worldwide. Many wildfires burn in living or a mixture of living and senescent vegetation. Therefore, it is necessary to understand the burning behavior of living fuels, in contrast to just dead or dried fuels, to more effectively support fire management decisions. In this study, the ignition and burning behaviors of needles placed in convective heat flux were evaluated. The species included longleaf pine (Pinuspalustris), Douglas-fir (Pseudotsuga menziesii), western red cedar (Thuja plicata), ponderosa pine (Pinus ponderosa), western larch (Larix occidentalis), pacific yew (Taxus brevifolia), white spruce (Picea glauca), and sagebrush (Artemisia tridentate). The ignition and burning behaviors were related to live fuel moisture content (LFMC), pilot flame temperatures, and convective heat fluxes. The different stages of ignition and burning were captured using high-speed imaging. In general, four burning stages can be observed: droplet ejection and burning, a transition stage, flaming combustion, and smoldering combustion. Ejection and subsequent burning of droplets can occur prior to sustained flaming ignition only in live fuels. For some species (e.g., longleaf pine, ponderosa pine, white spruce), droplet ejection and burning can reduce ignition times relative to dried fuel with lower LFMC. In general, the transition stage tends to take longer than the flaming and droplet stages (when these occur). During the transition stage, the fuels are heated, and pyrolysis occurs. Time-scales to ignition and the different stages of ignition and burning vary more among live fuels than dead and dried fuels. This conclusion indicates that other parameters, such as chemical composition and structural morphology of the fuel, can significantly influence the burning of live fuels.

Prescribed fire and other fuel-reduction treatments alter ground spider assemblages in a Southern Appalachian hardwood forest

Prescribed burns and understory thinnings are forest management practices aimed at reducing fuel loads to lessen wildfire threat in the Southern Appalachians, USA. Spiders play a critical role in forest ecosystems by controlling insect populations and providing an important food source for vertebrates. We used pitfall and colored pan traps to investigate how abundance, species richness, and diversity of spiders differed among three fuel reduction treatments administered repeatedly over a 15-year period and untreated controls. Additionally, we examined how spiders responded to one round (before and after) of fuel reduction treatments. We established treatments within the 15-year period as follows: mechanical understory removal (twice; M), prescribed burning (four times; B), mechanical understory removal followed one year later by high-severity prescribed burns and three subsequent burns (MB), and untreated controls (C). Our study period (2014–2016) occurred after multiple prescribed burns and two rounds of mechanical understory removal had occurred. Salticidae and Lycosidae were the two most commonly collected spider families in Southern Appalachian hardwood forests. Generally, we found increased spider abundances within all fuel-reduction treatments compared to controls. Individual spider families and species showed variable responses to treatments, but abundance of several spider families was greater in one or more fuel-reduction treatments than in controls. Additionally, abundance of several spider families and hunting/web building guilds (webs built for hunting purposes or defense) exhibited yearly differences to the last round of fuel-reduction treatments. Overall, our results suggest that changes in the overstory and understory of a forest are important drivers of regional spider abundance and assemblages, and forest management practices that modify forest structure can dramatically alter spider abundance and richness, usually in a positive manner.

Результаты анкетирования специалистов центров управления в кризисных ситуациях по вопросам реагирования на чрезвычайные ситуации

Introduction. Timely response to emergency situations is an urgent task in the framework of improving management in the structure of EMERCOM of Russian. The high need for the rapid creation and development of digital products, the management of digital services require a rethinking of approaches to the organizational and functional structures of government bodies. The rapid development of artificial intelligence models and algorithms inevitably leads to digital transformation processes, including at the stage of emergency response. To identify problems at the stage of responding to emergencies, a survey questionnaire was drawn up for specialists and employees of Crisis Management Centers of EMERCOM of Russia. The system of Crisis Management Centers of EMERCOM of Russia provides a solution to many complexly structured control tasks. Targets and goals. The aim of the work is to determine the priority of emergency criteria for their subsequent classification and search in the knowledge base. In order to achieve this goal, it is necessary to conduct a survey of specialists of Crisis Management Centers of EMERCOM of Russia on the widest range of issues in the field of emergency response. Methods. In the course of the work, statistical and dispersion-correlation analysis of the obtained data was carried out. Expert opinions were ranked, after which their consistency was determined. Results and its discussion. Conducted a survey of employees of Crisis Management Centers of EMERCOM of Russia (430 specialists) in 15 constituent entities of the Russian Federation, survey results were analyzed in order to obtain data to determine the number of response forces and means. A priority sequence of criteria has been obtained for three types of emergency situations: transport accidents, explosions (including those with subsequent burning) and (or) destruction (collapse) in buildings and structures, accidents in life support systems. This sequence is necessary to classify and search for emergencies in the knowledge base in order to determine the required number of forces and means to respond. Conclusions. The application of the results of the work will allow carrying out procedures for classifying emergencies, ranking their criteria, as well as determining the required number of forces and means for response. Keywords: survey, emergency, crisis management center, dispersion-correlation analysis, classification, ranking.

Phases and Time-Scales of Ignition and Burning of Live Fuels

Wildland fires impact ecosystems and communities worldwide. Many wildfires burn in living or a mixture of living and senescent vegetation. Therefore, it is necessary to understand the burning behavior of living fuels, in contrast to just dead or dried fuels, to more effectively support fire management decisions. In this study, the ignition and burning behaviors of needles placed in convective heat flux were evaluated. The species included longleaf pine (Pinus palustris), Douglas-fir (Pseudotsuga menziesii), western red cedar (Thuja plicata), ponderosa pine (Pinus ponderosa), western larch (Larix occidentalis), pacific yew (Taxus brevifolia), white spruce (Picea glauca), and sagebrush (Artemisia tridentate). The ignition and burning behaviors were related to live fuel moisture content (LFMC), pilot flame temperatures, and convective heat fluxes. The different phases of ignition and burning were captured using high-speed imaging. In general, four burning phases can be observed: droplet ejection and burning, a transition phase, flaming combustion, and smoldering combustion. Ejection and subsequent burning of droplets can occur prior to sustained flaming ignition only in live fuels. For some species (e.g., longleaf pine, ponderosa pine, white spruce) droplet ejection and burning can reduce ignition times relative to dried fuel with lower LFMC. In general, the transition phase tends to take longer than the flaming and droplet phases (when these occur). During the transition phase, the fuels are heated and pyrolysis occurs. Time-scales to ignition and the different phases of ignition and burning vary more among live fuels than dead and dried fuels. This conclusion indicates that other parameters, such as chemical composition and structural morphology of the fuel, can significantly influence the burning of live fuels.

Ignition and burning of the composite sample impacted by the Bunsen burner flame: A fully coupled simulation

Experimental study and three-dimensional simulation of warming up, ignition, and subsequent burning out of the composite material impacted by the attached Bunsen burner flame is presented. The specimen is the fiberglass-reinforced composite with the epoxy resin binder. In the experiment, vertical specimen was located above the laminar diffusion flame, and transient variation of specimen mass and surface temperatures was recorded until the matrix polymer burned out. In the simulations, thermal decomposition of the composite was evaluated by the in-house pyrolysis model Pyropolis coupled with the general-purpose CFD solver, which simulated the flames generated by the burner and by the combustible volatiles. Formal kinetics of thermal decomposition of matrix polymer and the heat of combustion of volatiles have been derived from the microscale combustion calorimetry measurements. The simulation results include favorable comparisons of experimental and predicted dynamics of material degradation and flame behavior. Transient spatial distributions of surface temperature, burning rate, and heat fluxes (net, radiative and convective) are demonstrated. This study is the step towards developing the computational framework capable of replicating and predicting the outcome of standard fire tests UL94 and VBB.

The M/V X-Press Pearl Nurdle Spill: Contamination of Burnt Plastic and Unburnt Nurdles along Sri Lanka's Beaches.

In May 2021, the M/V X-Press Pearl cargo ship caught fire 18 km off the west coast of Sri Lanka and spilled ∼1680 tons of spherical pieces of plastic or "nurdles" (∼5 mm; white in color). Nurdles are the preproduction plastic used to manufacture a wide range of end products. Exposure to combustion, heat, and chemicals led to agglomeration, fragmentation, charring, and chemical modification of the plastic, creating an unprecedented complex spill of visibly burnt plastic and unburnt nurdles. These pieces span a continuum of colors, shapes, sizes, and densities with high variability that could impact cleanup efforts, alter transport in the ocean, and potentially affect wildlife. Visibly burnt plastic was 3-fold more chemically complex than visibly unburnt nurdles. This added chemical complexity included combustion-derived polycyclic aromatic hydrocarbons. A portion of the burnt material contained petroleum-derived biomarkers, indicating that it encountered some fossil-fuel products during the spill. The findings of this research highlight the added complexity caused by the fire and subsequent burning of plastic for cleanup operations, monitoring, and damage assessment and provides recommendations to further understand and combat the impacts of this and future spills.

Previous wildfires and management treatments moderate subsequent fire severity

We investigated the relative importance of daily fire weather, landscape position, climate, recent forest and fuels management, and fire history to explaining patterns of remotely-sensed burn severity – as measured by the Relativized Burn Ratio – in 150 fires occurring from 2001 to 2019, which burned conifer forests of northeastern Washington State, USA. Daily fire weather, annual precipitation anomalies, and species’ fire resistance traits were important predictors of wildfire burn severity. In areas burned within the past two to three decades, prior fire decreased the severity of subsequent burns, particularly for the first 16 postfire years. In areas managed before a wildfire, thinning and prescribed burning treatments lowered burn severity relative to untreated controls. Prescribed burning was the most effective treatment at lowering subsequent burn severity, and prescribed burned areas were usually unburned or burned at low severity in subsequent wildfires. Patches that were harvested and planted <10 years before a wildfire burned with slightly higher severity. In areas managed within 5 years after an initial fire, postfire harvest and planting reduced prevalence of stand-replacing fire in reburns. However, overall, postfire management actions after a first wildfire only weakly influenced the severity of subsequent fires. The importance of fire-fire interactions to moderating burn severity establishes the importance of stabilizing feedbacks in active fire regimes, and our results demonstrate how silvicultural treatments can be combined with prescribed fire and wildfires to maintain resilient landscapes.

Ignition and Combustion Characteristics of Laser Irradiated Nanoparticle Pellets and Nanolaminates

This experimental study investigates low power (3 W) laser ignition and the subsequent burning characteristics of consolidated nanoparticle pellets and loose nanolaminate flakes. The effects of laser absorption, packing density (bulk porosity), and material properties on ignition are quantified, while simplified numerical models are used to examine their predominance. It is found that ignition of consolidated Al/CuO pellets is controlled by their effective thermal conductivity, such that ignition delay (approximately 1 to 100 ms) is minimized in the most porous specimen. However, the burning rate of these pellets is a compromise between the availability of reactive interfaces and the porosity allowing for gas expansion. On the other hand, ignition of loose nanolaminate flakes is predominately controlled by power absorption in the laser irradiated layer made of Al or , especially when the thickness of the layer is smaller than 60 nm. Ignition delay (approximately 0.1 to 1 ms) is tunable by adjusting the thickness of the top layer, which absorbs more radiation compared to a top Al layer. Moreover, the burning rate of the nanolaminate samples is a compromise between the layer thickness for power absorption and the equivalence ratio that controls the extent of reactions.

Carbon life cycle assessment of shelterbelts in Saskatchewan, Canada

Shelterbelts are rows of trees planted around farmyards and field for protection against soil erosion, promotion of biodiversity and wildlife habitat. Additionally, to carbon sequestration through growth in tree biomass and carbon sinks in agricultural soil. In recent years, removal of shelterbelts has become more common, as crop land is preferred under higher crop prices, resulting in increased GHG emissions and decreases in carbon sinks. It is likely that landowners are making decisions without the knowledge of carbon sequestered by these trees. In this study, the level of carbon sequestration for the six common shelterbelt tree species found in Saskatchewan (hybrid poplar, green ash, Manitoba maple, Scots pine, white spruce, and caragana) was estimated using a carbon - life cycle analysis method. Net amount of carbon sequestered was estimated for five sequestration/emission stages – 1) seedling production, 2) transportation of seedlings to farm, 3) planting, 4) maintenance, and 5) growth of shelterbelts on farm. Since some landowners are removing shelterbelts, a removal stage was also included. During removal of shelterbelts, CO2 emissions were produced through: (i) physical process of removing the trees and subsequent burning of the wood; and (ii) loss of soil carbon after the removal over a long period of time. The functional unit for the analysis was one linear kilometer of shelterbelt, the normal structure of shelterbelts on agricultural land. All emissions/sequestration levels were measured as carbon dioxide (CO2) by multiplying the molecular weight of carbon dioxide to that of carbon (44/12). Other than the growth stage of shelterbelts, all other stages contributed net greenhouse gas emissions, which offset by carbon sequestration during tree growth. Hybrid poplar is a rapidly growing tree and sequesters the most carbon of the six species in all soil zones. A one km long hybrid poplar shelterbelt sequestered upwards of 1923 t CO2 by age 60 years in the Brown soil zone, compared to 2086 t CO2 over the same period in the Black soil zone. In comparison, in the Brown soil zone, Manitoba maple and white spruce sequestered 756 and 732 t CO2, respectively over the same period. If a landowner decides to remove a 60-year-old shelterbelt, 1205 t CO2 is lost within a short period after removal, whereas 718 t of remaining CO2 is retained as dead organic matter, which is slowly released over a period. Although field shelterbelts may emit greenhouse gases in the earlier stages of development, overall, they are net sinks of carbon and can therefore play a significant role in Canada's plan to reduce GHG emissions from agriculture.

Smoldering and Flaming of Disc Wood Particles Under External Radiation: Autoignition and Size Effect

Wildfires are global issues that cause severe damages to the society and environment. Wood particles and firebrands are the most common fuels in wildfires, but the size effect on the flaming and smoldering ignitions as well as the subsequent burning behavior is still poorly understood. In this work, a well-controlled experiment was performed to investigate smoldering and flaming ignitions of stationary disc-shaped wood particles with different diameters (25–60 mm) and thicknesses (15–25 mm) under varying radiant heat flux. The ignition difficulty, in terms of the minimum heat flux, increases from smoldering ignition to piloted flaming ignition and then to flaming autoignition. As the sample thickness increases, the minimum heat flux, ignition temperature, and burning duration for flaming autoignition all increase, while the peak burning flux decreases, but they are insensitive to the sample diameter. During ignition and burning processes, the disc particle is deformed due to the interaction between chemical reactions and thermomechanical stresses, especially for smoldering. The characteristic thickness of the smoldering front on wood is also found to be 10–15 mm. This study sheds light on the size effect on the ignition of wood particles by wildfire radiation and helps understand the interaction between flaming and smoldering wildfires.

Impact of Wheat Harvest on Levels and Sources of PM2.5-associated PAHs in an Urban Area Located at the Center of Beijing-Tianjin-Hebei Region

Wheat harvest and subsequent straw burning for maize planting can cause severe PM2.5 and PAH pollutions and deteriorate the air quality of nearby cities in consequence. PM2.5 samples were collected in Baoding urban area (BUA) from June 18 to July 7 of 2019, during and after wheat harvest (DWH and AWH, respectively). The “Migration Effect” (i.e., PM2.5 and PAHs transferred from rural to urban during DWH and AWH, respectively) was proved by both the later time for appearance of peak values of PM2.5 and PAHs and the air mass origins in BUA. The daily average PM2.5 (reported in µg m–3) 137 of DWH was 2.58 times 53.1 of AWH for BUA, regardless of its lower levels than the corresponding 156 and 75.6 for an adjacent rural site (ARS). The reverse trend was found for PAH mass contents (in µg g–1), AWH possessed much higher value of 139 than 27.8 of DWH, while no significant fluctuations occurred for PAH concentrations due to the varied PM2.5 levels. Four PAH sources including biomass burning (BB), coal combustion (CC), vehicle exhaust (VE) and industrial emissions (IN) were identified using positive matrix factorization (PMF). BB was the biggest contributor during whole sampling period (WSP), followed by CC, VE, and IN. BB increased from 17.3% to 37.1% along with the transition from DWH to AWH, indicated the impact of straw burning for maize planting. High share of CC suggested that coal was still an important civil fuel. The strict emission reduction measures made the industry smallest contributor in BUA. Lower VE share in BUA than ARS demonstrated that influence of high-intensity operation of wheat harvesters and rotary cultivators.

Neutrophil-derived heparin binding protein triggers vascular leakage and synergizes with myeloperoxidase at the early stage of severe burns (With video).

BackgroundBurn shock caused by vascular leakage is one of the main causes of high mortality in severe burn injury. However, the pathophysiological mechanism of vascular leakage is still unclear. The purpose of this study was to explore the molecular mechanism of vascular leakage in the early stage of severe burn and provide a new target for the treatment of severe burns.MethodsNeutrophils were isolated from human peripheral blood by magnetic beads sorting. ELISA was used to detect neutrophil-derived granule proteins and glycocalyx injury products in plasma. The vascular leakage and neutrophil movement were assessed by in vivo laser confocal imaging in mice, and high-quality video were provided. Adhesion-related molecules were investigated by qRT-PCR. The damage to glycocalyx of mice vascular endothelial cells was observed by transmission electron microscope and scanning electron microscope. Proteomic analysis, flow cytometry and immunofluorescence were used to further study the relationship between human peripheral blood neutrophil-derived hypochlorite (HOCl) and CD44 of human vascular endothelial cells.ResultsIn this study, we found that rapidly increasing activated neutrophils secrete heparin binding protein (HBP) and myeloperoxidase (MPO) after severe burn injury. Increased HBP triggers vascular leakage with synergy of MPO, results in systemic edema and burn shock. Furthermore, we found that the MPO catalytic product HOCl but not MPO triggers CD44 extracellular domain shedding from vascular endothelial cells to damage the glycocalyx. Damage to the glycocalyx results in firm adhesion of neutrophils and increases vascular leakage. However, MPO inhibitors partially protect the glycocalyx of vascular endothelial cells. The combination of HBP and MPO inhibitors markedly reduces vascular leakage and systemic edema in the early stage of severe burns.ConclusionsTaken together, these data reveal that neutrophil-derived HBP and MPO play an important synergies role in triggering vascular leakage at the early stage of severe burns. Targeted intervention in these two biomolecules may introduce new strategies for helping to reduce large amount of fluid loss and subsequent burn shock.

Excerptum de Talmud: Study and Edition of a Thirteenth-Century Latin Translation by Isaac Lampurlanés Farré

Reviewed by: Excerptum de Talmud: Study and Edition of a Thirteenth-Century Latin Translation by Isaac Lampurlanés Farré Constant Mews Lampurlanés Farré, Isaac, Excerptum de Talmud: Study and Edition of a Thirteenth-Century Latin Translation (Contact and Transmission, 1), Turnhout, Brepols, 2020; hardback; pp. 302; 44 b/w tables; R.R.P. €85.00; ISBN 97820503586908. The so-called 'trial of the Talmud' that took place in Paris in 1240 and the subsequent burning of many copies of the Talmud in the following year is not a comfortable subject. This volume—the first to appear in a new Brepols series 'Contact and Transmission'—devoted to intercultural encounters from late antiquity to the early modern period provides a study in a meticulously documented critical edition of a Latin summary of the Talmud, along with an English translation, by Isaac Lampurlanés Farré. This summary, the so-called Excerptum de Talmud, is itself based on the much larger Extractiones de Talmud, a sequentially organized collection of almost 1900 passages culled from the Talmud, critically edited by Ulisse Ceccini and Óscar de la Cruz Palma in 2018 within the Brepols series 'Corpus Christianorum Continuatio Mediaevalis' (CCCM, 29, Brepols, 2018). All of these authors are part of an energetic research team based at Barcelona, devoted to studying the Latin Talmud. This study, edition, and translation lives up to the high editorial standards already established by that team. The first part of this volume contains three chapters that contextualize the summary that is edited and translated in its second part. The opening chapter describes the events that led up to the Paris trial of 1240. It started in 1238, when Nicholas Donin, a convert to Christianity from Judaism (who had himself been excommunicated by the Jewish community in Paris over a decade earlier) decided to take a list of thirty-five articles based on the Talmud to Pope Gregory IX. Lampurlanés Farré is more concerned to provide the basic facts in this process than to reflect on what might have provoked this extraordinary move. While Petrus Alphonsi and Peter the Venerable had quoted briefly from the Talmud a century earlier, the idea of pursuing a campaign against this text, held in such honour by Jewish communities, was completely original. With the formal end of the Albigensian Crusade in 1229, the idea of identifying the Talmud as a Jewish heresy that targeted Christianity provided justification for launching a vicious anti-Jewish campaign. One suspects that Odo of Châteauroux, appointed by William of Auvergne as Chancellor of the University of Paris in 1238, may have encouraged Donin to go to Rome and thus initiate an official ecclesiastical campaign against the Talmud. The trial that ensued, which involved rabbi Yehiel of Paris and Rabbi [End Page 228] Judah ben David of Melun, is recorded in a detailed Jewish account, as well as a briefer Christian narrative. This in turn led to mass burning (twenty-four cartloads, it is reported) of copies of the Talmud in 1241–42. For reasons that are not fully explained in this volume, the death of Pope Gregory IX on 22 August 1141, followed by the very short papacy of Celestine IV and a vacancy of some eighteen months prior to the enthronement of Innocent IV on 25 June 1243, resulted in a relaxation of the anti-Jewish campaign. While there are no references to the Talmud in the proceedings of the 1245 Council of Lyons, Odo of Châteauroux was certainly involved in promoting a second phase in proceedings against the Talmud in the years immediately following the Council. One suspects that the resumption of the campaign against the Talmud provided an opportunity for a hard-line faction within the Church to re-assert ecclesiastical authority, at least in Paris—perhaps as a move against those Christians who were interested in learning from Jewish tradition. Lampurlanés Farré focuses more on the textual production of the massive Extractiones de Talmud in the years 1245 and 1248, in which Donin was certainly involved, as was Odo of Châteauroux, who was made a cardinal in 1244. Odo's involvement in the affair led to a second trial of the Talmud...

Fire behavior of flame retarded sandwich structures containing PET foam cores and epoxy face sheets

AbstractWithin this work, the investigation on interactions of a phosphorus‐containing flame retardant (FR) DEPAl in epoxy face sheets and five different FRs in the PET‐foam core of a sandwich laminate on the fire behavior is focused. Fourteen different combinations of resin face sheets and PET foam cores are produced by vacuum assisted resin infusion (VARI). The combustion behavior of the sandwich laminates is tested by cone calorimetry. The time to ignition is lowered when a FR resin is used while the subsequent burning behavior is mainly influenced by the PET foam core. In order to evaluate the interactions of the flame retardants in the core and face sheet, a total improvement value (TIV) was set up which compares the performance related to the specific FR combinations. The highest TIV value (76%) indicating positive interactions with DEPAl was observed with a 2‐PSMP‐PET core, the lowest value (−2%) with a DEPZn‐PET core.

Urethral Orifice Genital Herpes Caused by HSV-1 in a Female Patient: A Case Report

Abstract Introduction: Genital herpes is one of the most common sexually transmitted infections worldwide. Most genital herpes occur on the genitalia, perineum, buttocks, upper thighs, or perianal areas. However, there were reports of rare cases of genital herpes on urethral orifice. Herein, we report a case of a patient who was diagnosed with urethral orifice genital herpes, a place likely to be ignored. Case presentation: A 53-year-old woman presented with vagina pruritus at first, with subsequent burning sensation around urethra. Mycostatin and mycospor were administered for the treatment of the pruritus. Then levofloxacin was prescribed. Finally, the patient was given treatment with acyclovir. Different from other cases, the investigation showed herpes simplex virus type 1 DNA positive and herpes simplex virus type 2 DNA negative by PCR. The patient was therefore diagnosed with genital herpes. Discussion: Most genital herpes happen on the genitalia, perineum, buttocks, upper thighs, or perianal areas. Few cases have been reported that genital herpes occurred on urethral orifice till now. Conclusion: If there is no typical symptoms that patient present with herpes simplex virus type 1 or 2 positive, urethral orifice genital herpes should be considered.