Burn Site Research Articles

The Clean Water Act and biosolids: A 45‐year chronological review of biosolids land application research in Colorado

The 1972 U.S. Clean Water Act set forth the generation of biosolids. In Colorado, biosolids land application research began in 1976 and continues today. Pastureland research suggested that sewage effluent could effectively be land applied to benefit aboveground plant growth and to polish water prior to reaching receiving waters. Forest wildfire-affected ecosystems can also benefit from biosolids applications; application rates of up to 80 Mg ha-1 can lead to greater plant establishment, soil microbial activity, and nutrient turnover and reduced nutrient and heavy metal concentrations in runoff below livestock and USEPA drinking water standards. Long-term (24-yr) observations in oil shale-mined lands showed that biosolids (up to 224 Mg ha-1 ) can have a positive effect on microbial-mediated nutrient cycling and, in turn, on aboveground plant community structure. Biosolids applications of up to 40 Mg ha-1 in high-elevation shrubland ecosystems, dominated by Mo-containing shale deposits, can aid in reducing imbalances between Mo and Cu in soils and plants; excessive plant Mo, when consumed by ruminants, can lead to molybdenosis. Biosolids and lime applications (both at 224 Mg ha-1 ) have been shown to improve long-term reclamation success on acid-generating, heavy metal-containing fluvial mine tailings. Thirty years of grazing land research, focused on soil and aboveground plant benefits, illustrate that soil health and plant productivity can be improved to the greatest extent at biosolids application rates close to 10 Mg ha-1 . Finally, 40 yr of dryland agroecosystem research (a) have helped identify biosolids N fertilizer equivalency (∼8kg N Mg-1 ) and thus dryland winter wheat application rates (e.g., 4.5-6.7 dry Mg ha-1 ); (b) have identified first-year mineralization rates of 25-32%; (c) dispute the "time bomb" theory by showing that plant metal uptake follows an exponential rise to a maximum; (d) showcase economic return to producers via increased wheat grain protein content; (e) suggest that biosolids-borne proteins and their degradation products are labile C and N sources; (f) have led to long-term tracking of micronutrients and heavy metals in soils and revealed that plants-soil concentrations will not lead to groundwater degradation and that plants are safe for human consumption; and (g) have shown that biosolids provide Zn, helping to overcome soil deficiencies and enhancing Zn biofortification in wheat grain. This latter point is important because ∼2 billion people globally suffer from Zn deficiencies. Forty-five years of research in Colorado have proven that biosolids can enhance environmental quality, improve soil health, and produce healthy food products.

The Impact of a Forest Fire Event on Moth Assemblages in Western Bohemia, Czech Republic

Fire has major impact on species diversity in natural ecosystems around the world. The consequences of fires for invertebrates can be immediate, and recovery of species assemblages may be a long-term process. We recorded moth communities from May to November 2019 in a pine forest in Western Bohemia, Czech Republic, where a local fire occurred in April of that year. We used UV light traps at one burned site and two neighboring unburned sites with a similar character as the burned site before the fire event. We analyzed moth assemblages using several species diversity indices – index of dominance, Shannon-Wiener index and Shannon-Wiener evenness, Simpson index, and Chao1 nonparametric estimation. We detected 67 species at the burned site, and 97 and 106 at the unburned sites. The three most frequently trapped species at all sites were Macaria liturata, Buphalus piniaria and Thera obeliscata, representing common forest geometrid moths. We observed a decline in species number and abundance at the burned site compared to the unburned sites, probably due to the direct mortality of larvae. On the contrary, the burned site was more diverse according to the diversity indices. The fire disrupted the original character of the coniferous forest, which was proved by a decline of species feeding on conifers and Vaccinium spp. The burned site attracted species associated with dry habitats such as Eublemma purpurina, Charissa obscurata and Scopula rubiginata. Even though wildfires are viewed negatively in general, they might temporarily enhance diversity in a homogeneous landscape.

Small herbivores with big impacts: Tundra voles (Microtus oeconomus) alter post-fire ecosystem dynamics.

Fire is an important ecological disturbance that can reset ecosystems and initiate changes in plant community composition, ecosystem biogeochemistry, and primary productivity. As herbivores rely on primary producers for food, changes in vegetation may alter plant-herbivore interactions with important-but often unexplored-feedbacks to ecosystems. Here we examined the impact of post-fire changes in plant community composition and structure on habitat suitability and rodent herbivore activity in response to a large, severe, and unprecedented fire in northern Alaskan tundra. In moist acidic tundra where the fire occurred, tundra voles (Microtus oeconomus) are the dominant herbivore and rely on the tussock forming sedge Eriophorum vaginatum for both food and nesting material. Tundra voles were 10 times more abundant at the burned site compared with nearby unburned tundra 7-12 years after the fire. Fire increased the habitat suitability for voles by increasing plant productivity and biomass, food quality, and cover through both taller vegetation and increased microtopography. As a result of elevated vole abundance, Eriophorum mortality caused by vole herbivory was two orders of magnitude higher than natural mortality and approached the magnitude of the mortality rate resulting directly from the fire. These findings suggest that post-fire increases in herbivore pressure on Eriophorum could, in turn, disrupt graminoid recovery and enhance shrub encroachment. Tundra state transitions from graminoid to shrub dominated are also evident following other disturbances and fertilization experiments, suggesting that as Arctic temperatures rise, greater available nutrients and increased frequencies of large-scale disturbances may also alter plant-animal interactions with cascading impacts on plant communities and ecosystem function.

Assessing the immediate impacts of the 2019/2020 bushfires on land snails in north-eastern New South Wales

ABSTRACT This study aimed to improve our understanding of the immediate response of 26 priority species of land snail that may have been severely impacted by the 2019/2020 megafire event in north-eastern New South Wales. Our study covered a range of ecosystem types over an area of approximately 20,400 km2. We searched 70 survey sites that differed in burn severity for all species of land snail visually on-site and by sifting leaf litter samples under a microscope in the laboratory. These survey sites were selected for representing pre-existing occurrence records of priority species at sites that differed in mapped fire severity classes as based on Fire Extent and Severity data available from public sources. We also surveyed unburnt sites for comparative purposes. We found that nearly all survey sites encompassed a patchwork of areas with different burn extent and severity and that more humid forest types were overall affected by lower fire extent and severity than surrounding more xeric forest types. Only one site with extreme fire extent and severity was surveyed. The survey covered 165 historical occurrence records, 96 of which (58%) were re-confirmed. We also found 55 new occurrence records, 11 of which were in burnt and 44 in unburnt sites. Burnt and unburnt sites showed slight, yet insignificant differences in the redetection rate of species, which was generally low (on average 50–65%). Our data does not reveal an association between the number of specimens found at sites and burn severity and extent (from unburnt to extreme burnt). While we infer that populations have declined in areas affected by more severe fires, we found proportions of the survey area to be affected by fires of lower severity, which likely did not substantially affect the size of local land snail populations. Based on this, we conclude that initial concerns that the bushfires had led to a substantial deterioration of the conservation status of land snails are not generally corroborated. Instead, we have assessed just 3 species (10% of all studied species) as of conservation concern and 7 species (23%) as near threatened due to direct impacts of the 2019/2020 megafires. However, the paucity of occurrence records for many species and our limited knowledge of their ecology hampers a more detailed assessment of the potential fire impacts on many species, including possible on-going threats. Long-term monitoring and research are critical to ensure effective management especially of narrow range endemics.

Aerosols optical and radiative properties in Indonesia based on AERONET version 3

Heterogeneity in seasonal aerosol types due to different sources, local characteristics, and meteorology lead to different optical and radiative properties from one place to another. This study analyzes the long-term averages of aerosol optical and radiative properties obtained by the Aerosol Robotic Network (AERONET) version 3 at four sites in Indonesia representing fire prone areas (Palangka Raya, Pontianak, Jambi: 2012–2020), and urban-industrial (Bandung: 2009–2018). We examined the seasonal variation of aerosol optical depth (AOD), Angstrom Exponent (AE), Precipitable Water Vapor (PWV), and Single Scattering Albedo (SSA) combined with meteorological parameters at these Indonesian sites. Multiple clustering techniques from different relationships among various aerosol optical and radiative parameters was employed to further study the aerosol type in respect to different seasonality. The results exhibited a distinct seasonal pattern at all sites except Bandung, whereas AOD increased owing to forest and peat fire outbreaks during the dry season. The trend in AOD annual depicts an increase in Bandung as emission from urban/industrial increases episodically, while it depicts a decrease at the three biomass burning sites. As AOD increased, Palangka Raya, Pontianak, and Jambi exhibited wider ranges of observed AE (1.2–1.8) and high FMF (>0.8) in the dry burning period (June to October). On the other hand, Bandung has more aerosol distribution in the range of FMF values 0.6–1 and AE 1–1.6, compared with other sites, suggesting contribution of complex aerosol emission from different sources and likely due to the formation of secondary aerosol production from trace gases. Palangka Raya, Pontianak, and Jambi exhibited non-absorbing characteristics, as indicated by high SSA (>0.95), high FMF, and high EAE values (1.2–1.7) with no discrepancy in seasonal patterns, implying that biomass burning aerosols in Indonesia tend to cool the atmosphere with strong scattering rather than absorbing. At Bandung, aerosols mixed with slightly absorbing and non-absorbing aerosols owing to urban and industrial emissions. This study lays a foundation for further research on the contribution of aerosol radiative forcing to climate within the complex aerosol and cloud environments in Indonesia.

Demographic and dietary responses of small mammals to high severity fire

ABSTRACT Populations of many animal species decline after fire, with some individuals killed during the fire and others succumbing to impoverished conditions in the post-fire environment. For individuals that survive a fire, an ability to exploit scarce resources in the burnt landscape is particularly important. In this study, we compared the numbers, survival and diets of three species of small mammal at two sites in tall open-forest in the Australian Capital Territory, Australia. The first site was subjected to a high severity experimental fire in February 1980, while the second nearby site was unburnt and served as a control. Relative numbers and survival of the Agile Antechinus (Antechinus agilis) and Mainland Dusky Antechinus (A. mimetes) declined post-fire and remained lower than in the control site until spring 1980 when populations at both sites crashed following the post-mating death of males. These patterns reversed for A. mimetes in 1981 and 1982 and for A. agilis in 1982, with numbers and survival then being higher in the burnt than in the control site. Relative numbers of the Bush Rat (Rattus fuscipes) increased in a similar manner in both sites until the end of the study after 29 months, and monthly survival remained high throughout. The diets of the three species were similar between the control and burnt site before the fire. In the four months post-fire the diets of the two Antechinus species in the burnt site contained fewer ground-dwelling invertebrates compared with the control, whereas the dietary diversity of R. fuscipes in the burnt site increased due to increased consumption of food groups such as grasses and ferns that otherwise were seldom eaten. The dietary diversity of all species was similar between the two sites 12–16 months post-fire. The results suggest that the fire had short-term effects on the two species of Antechinus, most likely by depleting populations of their prey, while the demography of R. fuscipes was scarcely affected by fire owing to its ability to switch food groups within its already omnivorous diet. Dietary flexibility may be an important but often overlooked mechanism facilitating species’ persistence in post-fire environments.

Pediatric major burns: a monocentric retrospective review of etiology and outcomes (2008–2020)

BackgroundBurns are one of the most common causes of mortality and morbidity among children. This study aims to assess the epidemiology of pediatric major burns in a third level hospital in Spain to evaluate demographics, etiology, and outcomes.MethodsA retrospective study was held by the Plastic, Reconstructive and Burn Surgery department of the hospital. We included 147 patients under 18 admitted to hospital between January 2008 and December 2020 who meet the inclusion criteria: partial thickness burns > 10% total body surface area (TBSA) in patients < 18 years old. Clinical data extracted included age, gender, date of admission, %TBSA, burn types, severity and sites of burn, length of stay, length of ventilator support, intensive care admission, blood transfusion, surgical interventions, and complications.ResultsThree groups of age were analyzed. The average %TBSA was 18.7 (SE 0.9). Scalds were the main mechanism of injury (70.1%) and upper extremity was the most frequent location affected (68%). The 28.6% of patients suffered some complication, but the mortality rate was low (0.7%). In our series, the group aged 13–18 showed significantly higher %TBSA, more number of surgeries and blood transfusions.ConclusionsScald burns are the most frequent mechanism of injury in pediatric burns. However, teenagers suffer more severe burns and complications, usually caused by flame. Despite the low mortality rates, more measures of prevention should be taken to increase children security.Level of evidence: Level IV, Risk/Prognostic.

DOZER LINES INFLUENCE POST-FIRE PLANT COMMUNITY RECOVERY

As wildfires increase in extent and intensity and threaten local communities, active suppression tactics are becoming more common, including the creation of fire lines. Post-fire, these sites can become populated with non-native species and risk type conversion if native species recovery is lacking. Minimal research exists on the plant community trajectory of these mechanically disturbed sites. We studied the 32-Fire located east of Chico, CA. A fire line approximately 0.5 km long ranging in width from 6–12.2 m was created by a bulldozer. To assess plant recovery, we established plots in three pre-fire vegetation types: California Black Oak (Quercus kelloggii Newb.), Manzanita (Arctostaphylos manzanita Parry), and Wedgeleaf Ceanothus (Ceanothus cuneatus [Hook.] Nutt.) within three disturbance levels: burned, unburned (reference), and disturbed dozer line. Sites were sampled in 2018 (six-months post-fire) and in 2019 (18-months post-fire). In 2019, dozer line sites in the Manzanita and Wedgeleaf Ceanothus vegetation types did not have the dominant species found in similar unburned or burned sites. Across all vegetation types, dozer line sites had significantly higher average percent non-native species cover, compared with respective burned (P < 0.001, 95% C.I. = 33.2, 64.8) and unburned areas (P < 0.001, 95% C.I. = -77.2, -45.5). While unburned Wedgeleaf sites average non-native cover was 11% (SD = 9) in 2018 and 20% (SD = 5) in 2019, Wedgeleaf dozer line sites average non-native cover remained high between survey years at approximately 85%. Manzanita dozer line sites had average nonnative cover of 76% (SD = 16) and 57% (SD = 25) in 2018 and 2019, respectively, while unburned Manzanita had 9% (SD = 9) and 16% (SD = 16). Manzanita and Wedgeleaf Ceanothus species present on the study site are obligate seeders. Since neither species survived the implementation of the dozer line and no new recruitment of these species was observed, future recruitment of obligate seeders in these areas is unlikely. This suggests that dozer line sites with obligate seeders as dominant or co-dominant species are at risk of type conversion from native chaparral to annual grasslands dominated by non-native species.

Variability of Permafrost and Landscape Conditions Following Forest Fires in the Central Yakutian Taiga Zone

In the last two decades in Central Yakutia, there has been a significant change in cryogenic landscapes related to climate warming and anthropogenic disturbances. This period is characterized by the activity of forest fires, which significantly impact permafrost landscapes. We observed the dynamics of cryogenic landscapes after a forest fire in 2001 at the Neleger station in Central Yakutia, 35 km northwest of Yakutsk. The observations included ground temperature and active layer thickness monitoring and statements of changes in the soil moisture content of the active layer. Increases in ground temperature, the active layer thickness, and soil moisture content on the burnt site after a forest fire in Neleger station were noted in the first six to seven years after the disturbance. We found that, following forest fires, permafrost progressively restabilizes as forest cover redevelops over time. The results of the studies will become the basis for planning restoration work after forest fires in permafrost landscapes of Central Yakutia.

Epidemiological and Clinical Characteristics of 5,569 Pediatric Burns in Central China From 2013 to 2019.

BackgroundPediatric burns of all the ages are prevalent worldwide, posing a severe health risk to children. This study aims to examine pediatric burns' clinical characteristics and epidemiology in central China.MethodsThe pediatric patients of the Burn Research Center, Department of the First People's Hospital of Zhengzhou City from 2013 to 2019 were retrospectively studied and the relevant data were collected from the hospitalized medical records [e.g., demographic, etiology, length of stay (LOS), age, gender, burn area and depth, number of surgeries, cost, and outcome].ResultsA total of 5,569 pediatric burn patients were included, accounting for 43.9% of the total burn population. Electric burns represented a relatively small proportion (1.17%) but were more likely to lead to disabilities or death than scalds (90.63%) and flames (5.12%). The median age was 2 years [interquartile range (IQR): 1–4] and the boys/girls ratio ranged from 1.3:1 to 1.6:1. The most commonly burnt anatomic sites were the limbs (38.3%), with a median %TBSA (total body surface area) of 6 (IQR: 4–10). The complications of shock and pneumonia accounted for 7.6 and 19.2%, respectively. The peak months of pediatric burns included January, May, and August and the rural/urban ratio reached 1.61:1. The percentage of burn wounds treated surgically increased considerably from 2013 to 2019 (3.8 vs. 37.8%). The median hospital LOS was 15 days (IQR: 8–28 days), with the three high-risk factors (e.g., more surgeries, more %TBSA, full-thickness skin burns). The median cost of hospitalization was 1,511 USD (IQR: 848–2,648 USD) and the main risk factors consisted of full-thickness burns, more %TBSA, longer LOS, and more surgical procedures. Among all the patients, LA50 was 78.63% (95% CI = 75.12–83.45) and the overall mortality reached 0.1% since seven deaths were recorded.ConclusionScalds, flames, contact, and chemicals are the main causes of burns among children aged 1–5 years in central China. Accordingly, various prevention strategies should be employed depending upon the cause of the burn.

Impact of roadside burning on genetic diversity in ahigh-biomass invasive grass.

The invasive grass–fire cycle is a widely documented feedback phenomenon in which invasive grasses increase vegetation flammability and fire frequency, resulting in further invasion and compounded effects on fire regimes. Few studies have examined the role of short‐term adaptation in driving the invasive grass–fire cycle, despite invasive species often thriving after introduction to new environments. We used a replicated (nine locations), paired sampling design (burn vs unburnt sites) to test the hypothesis that roadside burning increases genetic diversity and thus adaptive potential in the invasive, high‐biomass grass Cenchrus ciliaris. Between four and five samples per site (n = 93) were genotyped using the DArTseq platform, and we filtered the data to produce panels of 15,965 neutral and 5030 non‐neutral single nucleotide polymorphism (SNP) markers. Using fastSTRUCTURE, we detected three distinct genetic clusters with extremely high F ST values among them (0.94–0.97) suggesting three different cultivars. We found high rates of asexual reproduction, possibly related to clonality or apomixis common in this species. At three locations, burnt and unburnt sites were genetically different, but genetic structure was not consistently related to fire management across the study region. Burning was associated with high genetic diversity and sexual reproduction in one genetic cluster, but with low genetic diversity and clonality in another. Individual SNPs were associated with longitude and genetic clustering, but not with recent fire management. Overall, we found limited evidence that roadside burning consistently increased genetic diversity and adaptive potential in C. ciliaris; evolutionary and breeding history more strongly shaped genetic structure. Roadside burning could therefore continue to be used for managing biomass in this species, with continued monitoring. Our study provides a framework for detecting fire‐related changes on a genetic level–a process that could be used as an early warning system to detect the invasive grass–fire cycle in future.

Quantifying the post‐fire recovery of taxonomic and functional diversity of dung beetles in the Brazilian Pantanal

Abstract The Pantanal is the largest wetland in the world and a World Heritage Site. During 2019–2020, the Pantanal has experienced the most severe burning in its history, with vast destroyed areas of vegetation and killed wildlife. Since the long‐term damage caused by fire to the Pantanal is still unknown, understanding how the biodiversity responds to post‐fire disturbance over a short‐term is an important step for conservation initiatives. The authors studied the effects of fire on dung beetle communities, a recognised bioindicator group, in the Brazilian Pantanal. For this, the authors assessed the patterns of taxonomic and functional diversity between unburned and burned sites (16 months post‐fire). The authors found that taxonomic and functional diversity of dung beetles were similar between unburned and burned grasslands, but with a distinct taxonomic composition post‐fire. The functional traits composition was similar between unburned and burned sites, demonstrating that this metric is less sensitive to fire effects in the Brazilian Pantanal. The study's results provide evidence that dung beetles exhibit high resistance to the occurrence of fire and fast recovery from its consequences. Thus, due to its ecological functions (secondary seed dispersion, nutrient cycling and others), these insects may assist ecological restoration of burned sites, being useful tools in restoration approaches for areas of the Pantanal that have been affected by fire. Finally, combining traditional taxonomic community attributes with functional diversity measurements provides a more comprehensive picture of responses of dung beetle communities, post‐fire, over a short‐term in the Brazilian Pantanal.

Biomechanical modeling of novel high expansion auxetic skin grafts.

Over 20 million burn injuries are reported every year, with severe cases requiring skin grafting. Traditionally, split thickness skin grafts are prepared by excising a small portion of healthy skin and its incision patterning using a suitable meshing device, which allows the graft to be expanded beyond its capacity. To date, the maximum expansion achieved through skin grafting has been reported to be less than three times, which is not sufficient for covering large burn sites with limited donor site skin. In this work, we have attempted to study skin graft expansion potential with novel auxetic patterns, which are known to exhibit negative Poisson's effect. Two-layer skin graft models were developed using eight different auxetic incision patterns, and subjected to uniaxial and biaxial tensile strains. The Poisson's ratio, meshing ratio, and induced stresses were characterized for all graft models. The numerical results indicated expansion potentials greater than that of traditional skin grafts across all loads. Extremely high expansions (i.e., >30 times) were estimated for the I-Shaped Re-entrant and Rotating Triangles shaped auxetic models without rupture. Such pioneering findings are anticipated to initiate ground-breaking advances towards skin graft research and improved outcomes in burn surgeries.

Ecophysiological and Growth-Related Traits of Two Geophytes Three Years after the Fire Event in Grassland Steppe.

Deliblato Sands is the single largest expanse of sand in Europe. It is the most fire-prone area of Serbia due to the absence of surface water, sandy soils, specific microclimate conditions, and vegetation composition. Post-fire regeneration is a long-term process that includes many aspects of vegetation regrowth and habitat recovery. In the third year following one of the disastrous fires, the growth dynamics of two geophyte species in unburned and burned sites were studied. During the growing season, burned and unburned populations of Crocus reticulatus Steven ex Adam and Iris pumila L. were assessed for growth parameters (biomass production, specific leaf area, leaf area index) and leaf-level ecophysiological traits (photosystem II efficiency, chlorophyll amount, relative water content). Species acclimated differently to changed abiotic and biotic site conditions after the fire event. C. reticulatus burned and unburned populations differed significantly in terms of flowering phenology and ecophysiological traits, whereas I. pumila burned and unburned populations differed significantly in terms of growth parameters. The findings support the assertion that geophytes are generally well adapted to environmental disturbances. Species, however, responded differently to fire-induced changes in the physicochemical and biotic environment, depending on their ecological requirements and adaptive capacity.

Expansion potential of skin grafts with alternating slit based auxetic incisions

Due to a dearth of skin substitutes, severe burn injuries result in millions of deaths every year. Split thickness skin grafting, which involves the projection of a parallel incision pattern on a small section of excised healthy skin, is commonly used to improve the expansion and cover a large burn site. The true expansion capacity of such grafts is currently limited to less than three times, which is insufficient for treating severe burn damage. In this work, we investigated the expansion potential of skin grafts using alternating slit based auxetic incision designs, with the hypothesis that this would lead to greater expansion than standard graft models. Nine two-layer skin graft models were developed with varying slit lengths and spacing, and the Poisson's ratio, meshing ratios, and induced stresses were estimated under uniaxial and biaxial load tests. For up to 100% applied strains, the Poisson's ratio increased with increase in the unit cell spacing. For the biaxial tests, equal lengths of the slits of the pattern, with a high unit cell spacing, was found to lead to a greater skin cover and lower stress localization in the graft models. However, when the graft models were tested up to the ultimate tensile strength of skin, a low unit cell spacing was found to be more desirable. Maximum uniaxial and biaxial meshing ratios, approximately 13 and 5 times higher than that of traditional grafts respectively, were quantified. Such expansion potentials and stress estimations with skin grafts have not been reported previously and would be indispensable for ground breaking advances in burn surgery research.

Local injection of botulinum toxin type A (BTX-A) prevents scarring esophageal stricture caused by electrocautery in rabbit models.

BackgroundBenign esophageal strictures are common in clinical practice. The commonly used methods for preventing benign esophageal strictures still have many shortcomings. In this study, we investigated the preventive effect and possible mechanism of endoscopic local injection of botulinum toxin type A (BTX-A) on scarring esophageal stricture caused by electrocautery in rabbit models, with an attempt to provide a theoretical basis for the clinical application of BTX-A in the prevention of benign esophageal stricture.MethodsAdult male New Zealand rabbits were randomly divided into 4 groups: cautery group (cauterized with 30 W electrocoagulation power without other intervention), saline group (injected with normal saline at 4 spots in the local esophagus after modeling), BTX-A I group (injected with 10 U of BTX-A after modeling), and BTX-A II group (injected with 20 U of BTX-A after modeling). Body weight was measured at postoperative weeks 1, 2, and 4. Esophagography was performed, and the internal diameter of the esophagus was measured. The esophageal tissues were harvested for hematoxylin and eosin (HE) staining and Masson staining. Type I, type III collagen levels and the mRNA expression of transforming growth factor β1 (TGF-β1) in esophageal tissues were detected.ResultsCompared with the cautery and saline groups, the BTX-A I and BTX-A II groups had significantly higher body weight, larger esophageal internal diameter, lower type I and type III collagen levels, and lower TGF-β1 mRNA expression levels in esophageal tissues at postoperative week 4. Comparisons between the BTX-A I and BTX-A II groups showed no significant differences in terms of body weight, esophageal internal diameter, and type I collagen level at postoperative week 4. However, the BTX-A II group had a significantly lower type III collagen level and TGF-β1 mRNA expression level than the BTX-A I group.ConclusionsLocal injection of BTX-A can alleviate esophageal stricture after electrocautery and has a preventive effect on benign esophageal stricture caused by electrocautery in rabbits. The mechanism may be that BTX-A down-regulates the expression of TGF-β1 in the esophageal tissue at the burn site and reduces the deposition of collagen.

Verdwenen bos opnieuw op de kaart

Vanished forest back on the map Mapping woodland in the late medieval Netherlands based on the distribution of woodland-related place names In the Netherlands plans are being developed to increase woodland substantially. But where? And what should new stretches of woodland be like to fulfill their intended functions? Historical information may help answering these questions. However, only for the period after 1850 detailed nation-wide cartographic information is available. Initiated by the Cultural Heritage Agency of the Netherlands (rce) a big data analysis was carried out on a national scale to gain insight in the distribution and character of woodland in the late medieval period (1000-1500). Starting point was a database containing all 6284 Dutch place names. Medieval place names that refer to (the use of) woodland in general or to specific types of woodland were selected and mapped. The resulting distribution shows interesting regional differences but is distorted and incomplete. The next step is to supplement it by using national inventories of ‘ancient woodland’, historically known medieval woods, archaeological data on medieval charcoal burning sites and perhaps also known sites of ‘ancient woodland’ plant species. Regional inventories of field names will then be used to validate resulting spatial patterns.

Comparative study of three scores in predicting the death risk of severe burn patients

Objective: To explore the predictive values of the modified Baux score, Belgian Outcome in Burn Injury score, and Ryan score on the death risk of severe burn patients. Methods: A retrospective case series study was conducted. From February 2018 to November 2019, 260 severe burn patients who met the inclusion criteria were admitted to the Department of Burns of the First Affiliated Hospital of Nanchang University, including 158 males and 102 females, aged 36 (3, 53) years. According to the final outcome, the patients were divided into survival group (n=229) and death group (n=31). Data of patients were compared and statistically analyzed with chi-square test or Mann-Whitney U test between the two groups, including the gender, age, cause of burn, site of burn, total burn area, depth of burn, combined inhalation injury, and combined underlying diseases on admission, and the modified Baux score, Belgian Outcome in Burn Injury score, and Ryan score calculated based on part of the aforementioned data. The Kendall tau-b coefficient method was used to analyze the consistency of the above-mentioned three scores in 260 severe burn patients. The receiver operating characteristic (ROC) curves of the above-mentioned three scores predicting the death risk of 260 severe burn patients were drawn, and the area under the curve (AUC), the optimal threshold, and the sensitivity and specificity under the optimal threshold were calculated. The quality of AUC of the above-mentioned three scores was compared by Delong test. Results: The gender, site of burn, and depth of burn of patients between the two groups were all similar (P>0.05). The age, total burn area, proportion of flame burn, proportion of combined inhalation injury, and proportion of combined underlying diseases of patients in death group were significantly higher than those in survival group (with Z values of 5.53 and 17.78, respectively, χ2 values of 16.23, 15.89, and 17.78, respectively, P<0.01); the modified Baux score, Belgian Outcome in Burn Injury score, and Ryan score of patients in death group were 142 (115, 155), 7 (5, 7), 2 (2, 3), all significantly higher than 64 (27, 87), 1 (0, 3), 0 (0, 1) in survival group (with Z values of 7.91, 7.64, and 7.61, respectively, P<0.01). In 260 severe burn patients, the results between the modified Baux score and Ryan score, modified Baux score and Belgian Outcome in Burn Injury score, Ryan score and Belgian Outcome in Burn Injury score were significantly consistent (with Kendall tau-b coefficients of 0.75, 0.71, and 0.86, respectively, P<0.01). The AUCs of ROC curves of the modified Baux score, Belgian Outcome in Burn Injury score, and Ryan score for predicting the death risk of 260 severe burn patients were 0.92, 0.89, and 0.85, respectively (with 95% confidence intervals of 0.86-0.98, 0.83-0.95, and 0.78-0.93, respectively, P<0.01); the optimal thresholds were 106.5, 4.5, and 1.5 points, respectively; the sensitivity under the optimal threshold were 88.5%, 76.9%, and 73.1%, respectively, and the specificity under the optimal threshold were 88.5%, 87.2%, and 86.3%, respectively. The modified Baux score was similar to Belgian Outcome in Burn Injury score in the AUC quality (z=1.25, P>0.05), which were both significantly better than the AUC quality of Ryan score (with z values of 2.35 and 2.11, respectively, P<0.05). Conclusions: The modified Baux score, Belgian Outcome in Burn Injury score, and Ryan score have good ability in predicting the death risk of severe burn patients. From the perspective of clinical practice, the modified Baux score is more suitable as a predictive tool for the prognosis of severe burn patients.

Precise Quantification of Land Cover before and after Planned Disturbance Events with UAS-Derived Imagery

This paper introduces a detailed procedure to utilize the high temporal and spatial resolution capabilities of an unmanned aerial system (UAS) to document vegetation at regular intervals both before and after a planned disturbance, a key component in natural disturbance-based management (NDBM), which uses treatments such as harvest and prescribed burns toward the removal of vegetation fuel loads. We developed a protocol and applied it to timber harvest and prescribed burn events. Geographic image-based analysis (GEOBIA) was used for the classification of UAS orthomosaics. The land cover classes included (1) bare ground, (2) litter, (3) green vegetation, and (4) burned vegetation for the prairie burn site, and (1) mature canopy, (2) understory vegetation, and (3) bare ground for the timber harvest site. Sample datasets for both kinds of disturbances were used to train a support vector machine (SVM) classifier algorithm, which produced four land cover classifications for each site. Statistical analysis (a two-tailed t-test) indicated there was no significant difference in image classification efficacies between the two disturbance types. This research provides a framework to use UASs to assess land cover, which is valuable for supporting effective land management practices and ensuring the sustainability of land practices along with other planned disturbances, such as construction and mining.

Contrasting successional responses of soil bacteria and fungi to post-logging burn severity

Globally, forest ecosystems are increasingly impacted by natural and anthropogenic disturbances including fire, timber harvesting and land clearance. Understanding how soil bacteria and fungi are impacted by logging and burning is important for resource management, as these microbiota underpin many essential ecosystem processes such as nutrient cycling and soil formation. Using amplicon sequencing and qPCR of the bacterial 16S rRNA gene and fungal ITS1 region, we quantified the abundance, diversity, and composition of soil bacterial and fungal communities in undisturbed forest and adjacent logged and burnt sites, which included a mosaic of burning severities (unburnt, low severity and high severity burns). Our study was conducted over a 12-month time series post-burn, in the temperate wet eucalypt forests of Tasmania, Australia. We found that over this 12-month period i) after high severity burns, total abundance and diversity returned to pre-disturbance levels in bacterial communities but not in fungal communities and ii) for each disturbance severity, the composition of bacterial communities became more similar to the undisturbed reference communities over time, while fungal communities did not. We also characterised the succession of disturbance responsive taxa in logged and burnt communities, with the relative dominance of copiotrophic bacteria and fire-associated Ascomycota fungi shifting towards oligotrophic bacteria and fire-associated Basidiomycota fungi by 12-months. Further, we highlight specific taxa that respond positively or negatively to the impacts of fire disturbance and discuss the ecological implications of our findings for forest management.