Brain hemorrhage after electrical burn injury: Case report and probable mechanism.

PubMed

Axayacalt, Gutierrez Aceves Guillermo; Alejandro, Ceja Espinosa; Marcos, Rios Alanis; Inocencio, Ruiz Flores Milton; Alfredo, Herrera Gonzalez Jose

2016-01-01

High-voltage electric injury may induce lesion in different organs. In addition to the local tissue damage, electrical injuries may lead to neurological deficits, musculoskeletal damage, and cardiovascular injury. Severe vascular damage may occur making the blood vessels involved prone to thrombosis and spontaneous rupture. Here, we present the case of a 39-year-old male who suffered an electrical burn with high tension wire causing intracranial bleeding. He presented with an electrical burn in the parietal area (entry zone) and the left forearm (exit zone). The head tomography scan revealed an intraparenchimatous bleeding in the left parietal area. In this case, the electric way was the scalp, cranial bone, blood vessels and brain, upper limb muscle, and skin. The damage was different according to the dielectric property in each tissue. The injury was in the scalp, cerebral blood vessel, skeletal muscle, and upper limb skin. The main damage was in brain's blood vessels because of the dielectric and geometric features that lead to bleeding, high temperature, and gas delivering. This is a report of a patient with an electric brain injury that can be useful to elucidate the behavior of the high voltage electrical current flow into the nervous system.

The effect of adipose derived stromal vascular fraction on stasis zone in an experimental burn model.

PubMed

Eyuboglu, Atilla Adnan; Uysal, Cagri A; Ozgun, Gonca; Coskun, Erhan; Markal Ertas, Nilgun; Haberal, Mehmet

2018-03-01

Stasis zone is the surrounding area of the coagulation zone which is an important part determining the extent of the necrosis in burn patients. In our study we aim to salvage the stasis zone by injecting adipose derived stromal vascular fraction (ADSVF). Thermal injury was applied on dorsum of Sprague-Dawley rats (n=20) by the "comb burn" model as described previously. When the burn injury was established on Sprague-Dawley rats (30min); rat dorsum was separated into 2 equal parts consisting of 4 burn zones (3 stasis zone) on each pair. ADSVF cells harvested from inguinal fat pads of Sprague-Dawley rats (n=5) were injected on the right side while same amount of phosphate buffered saline (PBS) injected on the left side of the same animal. One week later, average vital tissue on the statis zone was determined by macroscopy, angiography and microscopy. Vascular density, inflammatory cell density, gradient of fibrosis and epithelial thickness were determined via immunohistochemical assay. Macroscopic stasis zone tissue viability (32±3.28%, 57±4.28%) (p<0.01), average number of vessels (10.28±1.28, 19.43±1.72) (p<0.01), capillary count (15.67±1.97, 25.35±2.15) (p<0.01) vascular density (1.55±0.38, 2.14±0.45) (p<0.01) epithelial thickness (0.014±0.009mm, 0.024±0.0011mm) were higher on ADSVF side. Fibrosis gradient (1.87±0.51, 1.50±0.43) (p<0.01) and inflammatory cell density (1.33±0.40, 1.20±0.32) (p<0.01) were higher on the PBS side. Macroscopic and microscopic findings determined that ADSVF has a statistically significant benefit for salvaging stasis zone on acute burn injuries. Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.

Water repellency and soil moisture variations under Rosmarinus officinalis in a burned soil

NASA Astrophysics Data System (ADS)

Gimeno-García, E.; Pascual-Aguilar, J. A.; Llovet, J.

2009-04-01

Mediterranean semi-arid landscapes are characterised by the patchiness of the vegetation cover, in which variations in the distribution pattern of soil water repellency (SWR) can be of major importance for their hydrological and geomorphological effects in burned areas, and also for their ecological implications concerning to the re-establishment of their plant cover. Within a broader research framework, the present work studies the influence of Rosmarinus officinalis vegetated patches on SWR in burned and unburned soils and its relationship with the field soil moisture content (SMC). The results presented here are the first step analysing the spatial pattern of sink and source runoff areas in a burned hillslope. The study area is located in the municipality of Les Useres, 40 km from Castellón city (E Spain), where a wildfire occurred in August 2007. We selected a burned SSE facing hillslope, located at 570 m a.s.l., with 12 ° slope angle, in which it was possible to identify the presence of two unique shrub species: Quercus coccifera L. and Rosmarinus officinalis L., which were distributed in a patchy mosaic. Twenty microsites with burned R. officinalis and eight at the nearest unburned area were selected. At the burned microsites, it was possible to distinguish three concentric zones (I, II and III) around the stumps showing differences on their soil surface appearance, which indicate a gradient of fire severity. Those differences were considered for soil sampling (1 sample per zone at each microsite, n= 84, form the first 2 cm of the mineral A horizon) and field soil moisture measurements determined by means of the moisture meter HH2 with ThetaProbe sensor type ML2x (5 measurements per zone at each microsite, n= 420), which were taken one day after the first rainfall event after fire, when 11 mm were registered in the study area. Results showed that the largest repellency persistence (measured by means of the Water Drop Penetration Time test, WDPT) was found close to the burned R. officinalis stumps, where all soil samples showed water repellency, with mean WDPT of 68 seconds. Generally, we observed a sharp hydrophobic/hydrophilic boundary between the zones I (stump) and II (intermediate). Soil samples from bare soil (zone III) were entirely wettable. At control microsites, SWR was present only in one of the unburned R. officinalis samples. On the basis that unburned microsites are representative of the pre-fire conditions at the burned ones, these results imply that fire caused a significant increase in SWR occurrence at the soil surface. Field SMC showed statistically significant differences between the three zones. Both control and burned microsites showed the same trend, with an increasing gradient towards the outer zone. Furthermore, burned microsites showed larger differences in SMC between zone I and zone III (18% and 27%, respectively) than the unburned ones. It could be explained because at burned stumps, the largest persistence of water repellency and the highest SOM content might decrease the wettability of aggregates, slowing their rates of wetting, which might not occur at all during the rainstorms. In fact, there was obtained a significant and negative Pearson's correlation coefficients between SMC and WDPT, and between SMC and SOM at burned microsites. However, no correlation between field SMC and WDPT was found from control microsites. Moreover, at the burned microsites, the partial correlation analysis with SOM as control variable revealed that SMC and WDPT were influenced by the SOM. In addition, it is necessary to consider the existence of root channels with the development of preferential flow pathways, which could enhance deeper water infiltration in the stump areas. These results provide evidences of the importance of microsite soil surface properties on SMC variability on semiarid burned slopes. The existence of SWR and lowest SMC detected at burned stumps opposite to the highest SMC after rainfall and the absence of SWR in burned bare soil zones could be key factors for the differences in overland flow and erosional response of burned areas characterised by the patchiness of the vegetation cover.

Delayed Gratification Habitable Zones (DG-HZs): When Deep Outer Solar System Regions Become Balmy During Post-Main Sequence Stellar Evolution

NASA Astrophysics Data System (ADS)

Stern, S. A.

2002-09-01

Late in the Sun's evolution it, like all low and moderate mass stars, it will burn as a red giant, generating 1000s of solar luminosities for a few tens of millions of years. A dozen years ago this stage of stellar evolution was predicted to create observable sublimation signatures in systems where Kuiper Belts (KBs) are extant (Stern et al. 1990, Nature, 345, 305); recently, the SWAS spacecraft detected such systems (Melnick et al. 2001, 412, 160). During the red giant phase, the habitable zone of our solar system will lie in the region where Triton, Pluto-Charon, and KBOs orbit. Compared to the 1 AU habitable zone where Earth resided early in the solar system's history, this "delayed gratification habitable zone (DG-HZ)" will enjoy a far less biologically hazardous environment-- with far lower harmful UV radiation levels from the Sun, and a far quieter collisional environment. Objects like Triton, Pluto-Charon, and KBOs, which are known to be rich in both water and organics, will then become possible sites for biochemical and perhaps even biological evolution. The Sun's DG-HZ may only be of academic interest owing to its great separation from us in time. However, several 108 approximately solar-type Milky Way stars burn as luminous red giants today. Thus, if icy-organic objects are common in the 20-50 AU zones of these stars, as they are in our solar system (and as inferred in numerous main sequence stellar disk systems), then DG-HZs form a kind of niche habitable zone that is likely to be numerically common in the galaxy. I will show the calculated temporal evolution of DG-HZs around various stellar types using modern stellar evolution luminosity tracks, and then discuss various aspects of DG-HZs, including the effects of stellar pulsations and mass loss winds. This work was supported by NASA's Origins of Solar Systems Program.

Effect of the historical land use on the structure of forest soils in European Russia

NASA Astrophysics Data System (ADS)

Bobrovskii, M. V.

2010-12-01

The morphological structure of the soils in the forest areas of European Russia was analyzed. It was shown that most of the soils were formed under the impact of both biotic and anthropogenic factors. Soils with poorly differentiated profiles without podzolization features are typical for the least disturbed forest ecosystems. The presence of an eluvial (EL) horizon is associated with the signs of old plowing and (or) fires. The character and rate of the soil cover transformation under various impacts of the historical land use (felling, plowing, pasturing, burning, etc.) are discussed. The technologies of the main traditional farming systems in the forest zone of European Russia (slash-and-burn, fallow, and shifting farming systems) are considered; their effect on the long-term dynamics of the soil cover is estimated. Farming and the related impacts of historical land use can be a major reason for the formation of degraded soils in the forest zone of European Russia.

Deep mixing of 3He: reconciling Big Bang and stellar nucleosynthesis.

PubMed

Eggleton, Peter P; Dearborn, David S P; Lattanzio, John C

2006-12-08

Low-mass stars, approximately 1 to 2 solar masses, near the Main Sequence are efficient at producing the helium isotope 3He, which they mix into the convective envelope on the giant branch and should distribute into the Galaxy by way of envelope loss. This process is so efficient that it is difficult to reconcile the low observed cosmic abundance of 3He with the predictions of both stellar and Big Bang nucleosynthesis. Here we find, by modeling a red giant with a fully three-dimensional hydrodynamic code and a full nucleosynthetic network, that mixing arises in the supposedly stable and radiative zone between the hydrogen-burning shell and the base of the convective envelope. This mixing is due to Rayleigh-Taylor instability within a zone just above the hydrogen-burning shell, where a nuclear reaction lowers the mean molecular weight slightly. Thus, we are able to remove the threat that 3He production in low-mass stars poses to the Big Bang nucleosynthesis of 3He.

Landscape Patterns of Burn Severity in the Soberanes Fire of 2016

NASA Technical Reports Server (NTRS)

Potter, Christopher

2016-01-01

The Soberanes Fire started on July 22, 2016 in Monterey County on the California Central Coast from an illegal campfire. This fire burned for 10 weeks at a record cost of more than $208 million for protection and control. A progressive analysis of the normalized burn ratio from the Landsat satellite showed that the final high burn severity (HBS) area for the Soberanes Fire comprised 22 percent of the total area burned, whereas final moderate burn severity (MBS) area comprised about 10 percent of the total area burned of approximately 53,470 ha (132,130 acres). The resulting landscape pattern of burn severity classes from the 2016 Soberanes Fire revealed that the majority of HBS area was located in the elevation zone between 500 and 1000 m, in the slope zone between 15 percent and 30 percent, or on south-facing aspects.

Monitoring the impact of straw burning on particulate pollution using satellite and in-situ observations in the North China Plain

NASA Astrophysics Data System (ADS)

Zeng, C.

2015-12-01

The North China Plain is one of the main grain producing areas of China, but is also a severe straw burning zone. Winter wheat and summer corn harvests in this area usually occur from the beginning of Jun and Oct, respectively. After harvest, farmers usually burn out the remaining straw for convenience. However, straw burning can release a large quantity of air pollutants and can consequently result in a significant deterioration in regional air quality. To monitor the impact of straw burning on particulate pollution, daily MODIS thermal anomaly products (MOD14 and MYD14) were used to identify dates and regions of straw burning. Then the corresponding MODIS AOD products (MOD04 and MYD04) and particulate matter (PM) concentration observations from ground stations were integrated using a geostatistical method. By combining the accurate station-based PM observations and satellite data of well spatial coverage, PM concentration distribution maps were generated. Meanwhile, NCEP reanalysis data were used to obtain the corresponding surface wind pattern maps. Preliminary results show that satellite and station-based observations can indicate the impact of straw burning on PM pollution during harvest time. Air qualities during these times are obviously affected by the straw burning and surface wind field. Moreover, the air quality of the southeast study region is susceptible to the straw burning in adjacent areas due to the characteristic of the terrain.

Recent changes in annual area burned in interior Alaska: The impact of fire management

USGS Publications Warehouse

Calef, M.P.; Varvak, Anna; McGuire, A. David; Chapin, F. S.; Reinhold, K. B.

2015-01-01

The Alaskan boreal forest is characterized by frequent extensive wildfires whose spatial extent has been mapped for the past 70 years. Simple predictions based on this record indicate that area burned will increase as a response to climate warming in Alaska. However, two additional factors have affected the area burned in this time record: the Pacific decadal oscillation (PDO) switched from cool and moist to warm and dry in the late 1970s and the Alaska Fire Service instituted a fire suppression policy in the late 1980s. In this paper a geographic information system (GIS) is used in combination with statistical analyses to reevaluate the changes in area burned through time in Alaska considering both the influence of the PDO and fire management. The authors found that the area burned has increased since the PDO switch and that fire management drastically decreased the area burned in highly suppressed zones. However, the temporal analysis of this study shows that the area burned is increasing more rapidly in suppressed zones than in the unsuppressed zone since the late 1980s. These results indicate that fire policies as well as regional climate patterns are important as large-scale controls on fires over time and across the Alaskan boreal forest.

Fort Independence: An Eighteenth-Century Frontier Homesite and Militia Post in South Carolina.

DTIC Science & Technology

1982-12-01

zone was designated Zone 3. The matrix was a moist , black muck with some rocks present, as well as chunks of burned and unburned logs, a 60 x 90cm...area of strong Tory sentiment, Fort ." Independence was important in maintaining South Carolina’s frontier at a critical time. The fort was burned by...Fort Independence was important in maintaining South Carolina’s frontier at a critical time. The fort was burned by Tories in early 1779

Multifuel evaluation of rich/quench/lean combustor

NASA Technical Reports Server (NTRS)

Novick, A. S.; Troth, D. L.; Notardonato, J.

1982-01-01

Test results on the RQL low NO(x) industrial gas turbine engine are reported. The air-staged combustor comprises an initial rich burning zone, followed by a quench zone, and a lean reaction and dilution zone. The combustor was tested as part of the DoE/NASA program to define the technology for developing a durable, low-emission gas turbine combustor capable of operation with minimally processed petroleum residual, synthetic, or low/mid-heating value gaseous fuels. The properties of three liquid and two gaseous fuels burned in the combustor trials are detailed. The combustor featured air staging, variable geometry, and generative/convective cooling. The lean/rich mixtures could be varied in zones simultaneously or separately while maintaining a specified pressure drop. Low NO(x) and smoke emissions were produced with each fuel burned, while high combustor efficiencies were obtained.

Performance of a Model Rich Burn-quick Mix-lean Burn Combustor at Elevated Temperature and Pressure

NASA Technical Reports Server (NTRS)

Peterson, Christopher O.; Sowa, William A.; Samuelsen, G. S.

2002-01-01

As interest in pollutant emission from stationary and aero-engine gas turbines increases, combustor engineers must consider various configurations. One configuration of increasing interest is the staged, rich burn - quick mix - lean burn (RQL) combustor. This report summarizes an investigation conducted in a recently developed high pressure gas turbine combustor facility. The model RQL combustor was plenum fed and modular in design. The fuel used for this study is Jet-A which was injected from a simplex atomizer. Emission (CO2, CO, O2, UHC, NOx) measurements were obtained using a stationary exit plane water-cooled probe and a traversing water-cooled probe which sampled from the rich zone exit and the lean zone entrance. The RQL combustor was operated at inlet temperatures ranging from 367 to 700 K, pressures ranging from 200 to 1000 kPa, and combustor reference velocities ranging from 10 to 20 m/s. Variations were also made in the rich zone and lean zone equivalence ratios. Several significant trends were observed. NOx production increased with reaction temperature, lean zone equivalence ratio and residence time and decreased with increased rich zone equivalence ratio. NOx production in the model RQL combustor increased to the 0.4 power with increased pressure. This correlation, compared to those obtained for non-staged combustors (0.5 to 0.7), suggests a reduced dependence on NOx on pressure for staged combustors. Emissions profiles suggest that rich zone mixing is not uniform and that the rich zone contributes on the order of 16 percent to the total NOx produced.

Prehospital burn management in a combat zone.

PubMed

Lairet, Kimberly F; Lairet, Julio R; King, Booker T; Renz, Evan M; Blackbourne, Lorne H

2012-01-01

The purpose of this article is to provide a descriptive study of the management of burns in the prehospital setting of a combat zone. A retrospective chart review was performed of U.S. casualties with >20% total-body-surface-area thermal burns, transported from the site of injury to Ibn Sina Combat Support Hospital (CSH) between January 1, 2006, and August 30, 2009. Ibn Sina CSH received 225 burn casualties between January 2006 and August 2009. Of these, 48 met the inclusion criteria. The mean Injury Severity Score was 31.7 (range 4 to 75). Prehospital vascular access was obtained in 24 casualties (50%), and 20 of the casualties received fluid resuscitation. Out of the 48 casualties enrolled, 28 (58.3%) did not receive prehospital fluid resuscitation. Of the casualties who received fluid resuscitation, nearly all received volumes in excess of the guidelines established by the American Burn Association and those recommended by the Committee for Tactical Combat Casualty Care. With regard to pain management in the prehospital setting, 13 casualties (27.1%) received pain medication. With regard to the prehospital fluid resuscitation of primary thermal injury in the combat zone, two extremes were noted. The first group did not receive any fluid resuscitation; the second group was resuscitated with fluid volumes higher than those expected if established guidelines were utilized. Pain management was not uniformly provided to major burn casualties, even in several with vascular access. These observations support improved education of prehospital personnel serving in a combat zone.

Characteristics and source apportionment of organic matter in PM(2.5) from cities in different climatic zones of China

NASA Astrophysics Data System (ADS)

Feng, Jialiang

For the first time, the dependency of the characteristics of organic matter in PM2.5 on geographical and climatic zones in three metropolitan cities of China was studied. Seasonal samples were collected at suburban and urban sites in Beijing, Shanghai and Guangzhou in 2002 and 2003. To further support the above study, seasonal samples were also collected at Changdao Island, a remote island, in Bohai Sea/Yellow Sea. Concentrations of organic carbon (OC), elemental carbon (EC), water-soluble organic carbon (WSOC), and solvent-extractable organic compounds (SEOC) were analyzed. The characteristics of the n-alkanes, polycyclic aromatic hydrocarbons, n-fatty acids, n-alkanols and molecular markers such as triterpanes were determined and used for source identification. Source apportionment was complemented by Chemical Mass Balance (CMB) modeling using the measured organic species as tracers. The impact of wind speed and wind direction on air quality was studied by back trajectory calculations and analysis. In general, traffic emissions were the largest contributors of OC followed by coal burning, kitchen emissions, vegetative detritus and biomass burning. However, in the space-heating season in Northern China, coal burning was the most important contributor of OC in the suburban areas of Beijing and at Changdao. Beijing had the highest concentration of organic aerosol followed by Guangzhou and Shanghai, while seasonal variation was in reverse order. Dispersion conditions determined by local topographies and meteorology were responsible for this trend. Contrary to common understanding, pollutant concentrations at the suburban sites were higher than the urban sites in all three cities. The main reason was the rapid urbanization of the suburban areas in the immediate vicinity of urban centers since China opened up for economic development, in addition, large numbers of manufacturing plants were relocated from the cities to the countryside in an attempt to clean up the urban environment. WSOC/TC ratios were comparable in all three cities at 0.2-0.3 and this value can be considered typical for urban aerosols from Chinese cities. Similar PAH/ALK ratios were found in the three cities, and PAHs were from a mixed contribution of coal burning and engine exhaust. More than half of the resolved SEOC was found to be n-fatty acids and they were mainly from kitchen emissions based on source profile comparisons and CMB analysis. The increase of contribution from coal burning in Beijing due to space heating was identified by the different distribution of triterpanes in summer and winter. The relative concentrations of semivolatile fossil fuel residue n-alkanes (<=C26) were inversely dependent on the ambient temperature. Similar trend was found in the concentrations of the semivolatile PAHs (molecular weight <=228). This was mainly caused by the gas/particle partitioning of semivolatile species in the different climatic zones. The enrichment of higher molecular weight plant wax compounds from Beijing to Shanghai to Guangzhou was a reflection of the variations of the vegetation in the different climatic zones. The seasonal variations in the concentrations and compositions of organic matter at Changdao were similar to the three cities, especially to Beijing. The remote island was also impacted by anthropogenic pollutants, and transported particles played a significant role in the contribution of the organic matter exemplified by the high WSOC/TC, low C18:1/C18 fatty acid, and high BeP/(BeP+BaP) ratios.

European Regional Climate Zone Modeling of a Commercial Absorption Heat Pump Hot Water Heater

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharma, Vishaldeep; Shen, Bo; Keinath, Chris

2017-01-01

High efficiency gas-burning hot water heating takes advantage of a condensing heat exchanger to deliver improved combustion efficiency over a standard non-condensing configuration. The water heating is always lower than the gas heating value. In contrast, Gas Absorption Heat Pump (GAHP) hot water heating combines the efficiency of gas burning with the performance increase from a heat pump to offer significant gas energy savings. An ammonia-water system also has the advantage of zero Ozone Depletion Potential and low Global Warming Potential. In comparison with air source electric heat pumps, the absorption system can maintain higher coefficients of performance in coldermore » climates. In this work, a GAHP commercial water heating system was compared to a condensing gas storage system for a range of locations and climate zones across Europe. The thermodynamic performance map of a single effect ammonia-water absorption system was used in a building energy modeling software that could also incorporate the changing ambient air temperature and water mains temperature for a specific location, as well as a full-service restaurant water draw pattern.« less

Deep Mixing of 3He: Reconciling Big Bang and Stellar Nucleosynthesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eggleton, P P; Dearborn, D P; Lattanzio, J

2006-07-26

Low-mass stars, {approx} 1-2 solar masses, near the Main Sequence are efficient at producing {sup 3}He, which they mix into the convective envelope on the giant branch and should distribute into the Galaxy by way of envelope loss. This process is so efficient that it is difficult to reconcile the low observed cosmic abundance of {sup 3}He with the predictions of both stellar and Big Bang nucleosynthesis. In this paper we find, by modeling a red giant with a fully three-dimensional hydrodynamic code and a full nucleosynthetic network, that mixing arises in the supposedly stable and radiative zone between themore » hydrogen-burning shell and the base of the convective envelope. This mixing is due to Rayleigh-Taylor instability within a zone just above the hydrogen-burning shell, where a nuclear reaction lowers the mean molecular weight slightly. Thus we are able to remove the threat that {sup 3}He production in low-mass stars poses to the Big Bang nucleosynthesis of {sup 3}He.« less

Beneficial Effects of Hydrogen-Rich Saline on Early Burn-Wound Progression in Rats

PubMed Central

Guo, Song Xue; Jin, Yun Yun; Fang, Quan; You, Chuan Gang; Wang, Xin Gang; Hu, Xin Lei; Han, Chun-Mao

2015-01-01

Introduction Deep burn wounds undergo a dynamic process known as wound progression that results in a deepening and extension of the initial burn area. The zone of stasis is more likely to develop more severe during wound progression in the presence of hypoperfusion. Hydrogen has been reported to alleviate injury triggered by ischaemia/reperfusion and burns in various organs by selectively quenching oxygen free radicals. The aim of this study was to investigate the possible protective effects of hydrogen against early burn-wound progression. Methods Deep-burn models were established through contact with a boiled, rectangular, brass comb for 20 s. Fifty-six Sprague-Dawley rats were randomly divided into sham, burn plus saline, and burn plus hydrogen-rich saline (HS) groups with sacrifice and analysis at various time windows (6 h, 24 h, 48 h) post burn. Indexes of oxidative stress, apoptosis and autophagy were measured in each group. The zone of stasis was evaluated using immunofluorescence staining, ELISA, and Western blot to explore the underlying effects and mechanisms post burn. Results The burn-induced increase in malondialdehyde was markedly reduced with HS, while the activities of endogenous antioxidant enzymes were significantly increased. Moreover, HS treatment attenuated increases in apoptosis and autophagy postburn in wounds, according to the TUNEL staining results and the expression analysis of Bax, Bcl-2, caspase-3, Beclin-1 and Atg-5 proteins. Additionally, HS lowered the level of myeloperoxidase and expression of TNF-α, IL-1β, and IL-6 in the zone of stasis while augmenting IL-10. The elevated levels of Akt phosphorylation and NF-κB p65 expression post burn were also downregulated by HS management. Conclusion Hydrogen can attenuate early wound progression following deep burn injury. The beneficial effect of hydrogen was mediated by attenuating oxidative stress, which inhibited apoptosis and inflammation, and the Akt/NF-κB signalling pathway may be involved in regulating the release of inflammatory cytokines. PMID:25874619

Endothelial necrosis at 1h post-burn predicts progression of tissue injury

PubMed Central

Hirth, Douglas; McClain, Steve A.; Singer, Adam J.; Clark, Richard A.F.

2013-01-01

Burn injury progression has not been well characterized at the cellular level. To define burn injury progression in terms of cell death, histopathologic spatiotemporal relationships of cellular necrosis and apoptosis were investigated in a validated porcine model of vertical burn injury progression. Cell necrosis was identified by High Mobility Group Box 1 protein and apoptosis by Caspase 3a staining of tissue samples taken 1h, 24h and 7 days post-burn. Level of endothelial cell necrosis at 1h was predictive of level of apoptosis at 24h (Pearson's r=0.87) and of level of tissue necrosis at 7 days (Pearson's r=0.87). Furthermore, endothelial cell necrosis was deeper than interstitial cell necrosis at 1h (p<0.001). Endothelial cell necrosis at 1h divided the zone of injury progression (Jackson's zone of stasis) into an upper subzone with necrotic endothelial cells and initially viable adnexal and interstitial cells at 1h that progressed to necrosis by 24h, and a lower zone with initially viable endothelial cells at 1h, but necrosis and apoptosis of all cell types by 24h. Importantly, this spatiotemporal series of events and rapid progression resembles myocardial infarction and stroke, and implicates mechanisms of these injuries, ischemia, ischemia reperfusion, and programmed cell death, in burn progression. PMID:23627744

Initial fuel temperature effects on burning rate of pool fire.

PubMed

Chen, Bing; Lu, Shou-Xiang; Li, Chang-Hai; Kang, Quan-Sheng; Lecoustre, Vivien

2011-04-15

The influence of the initial fuel temperature on the burning behavior of n-heptane pool fire was experimentally studied at the State Key Laboratory of Fire Science (SKLFS) large test hall. Circular pool fires with diameters of 100mm, 141 mm, and 200 mm were considered with initial fuel temperatures ranging from 290 K to 363 K. Burning rate and temperature distributions in fuel and vessel wall were recorded during the combustion. The burning rate exhibited five typical stages: initial development, steady burning, transition, bulk boiling burning, and decay. The burning rate during the steady burning stage was observed to be relatively independent of the initial fuel temperature. In contrast, the burning rate of the bulk boiling burning stage increases with increased initial fuel temperature. It was also observed that increased initial fuel temperature decreases the duration of steady burning stage. When the initial temperature approaches the boiling point, the steady burning stage nearly disappears and the burning rate moves directly from the initial development stage to the transition stage. The fuel surface temperature increases to its boiling point at the steady burning stage, shortly after ignition, and the bulk liquid reaches boiling temperature at the bulk boiling burning stage. No distinguished cold zone is formed in the fuel bed. However, boiling zone is observed and the thickness increases to its maximum value when the bulk boiling phenomena occurs. Copyright © 2011 Elsevier B.V. All rights reserved.

Orbital Decay in Binaries with Evolved Stars

NASA Astrophysics Data System (ADS)

Sun, Meng; Arras, Phil; Weinberg, Nevin N.; Troup, Nicholas; Majewski, Steven R.

2018-01-01

Two mechanisms are often invoked to explain tidal friction in binary systems. The ``dynamical tide” is the resonant excitation of internal gravity waves by the tide, and their subsequent damping by nonlinear fluid processes or thermal diffusion. The ``equilibrium tide” refers to non-resonant excitation of fluid motion in the star’s convection zone, with damping by interaction with the turbulent eddies. There have been numerous studies of these processes in main sequence stars, but less so on the subgiant and red giant branches. Motivated by the newly discovered close binary systems in the Apache Point Observatory Galactic Evolution Experiment (APOGEE-1), we have performed calculations of both the dynamical and equilibrium tide processes for stars over a range of mass as the star’s cease core hydrogen burning and evolve to shell burning. Even for stars which had a radiative core on the main sequence, the dynamical tide may have very large amplitude in the newly radiative core in post-main sequence, giving rise to wave breaking. The resulting large dynamical tide dissipation rate is compared to the equilibrium tide, and the range of secondary masses and orbital periods over which rapid orbital decay may occur will be discussed, as well as applications to close APOGEE binaries.

Astaxanthin protects against early burn-wound progression in rats by attenuating oxidative stress-induced inflammation and mitochondria-related apoptosis

PubMed Central

Fang, Quan; Guo, Songxue; Zhou, Hanlei; Han, Rui; Wu, Pan; Han, Chunmao

2017-01-01

Burn-wound progression can occur in the initial or peri-burn area after a deep burn injury. The stasis zone has a higher risk of deterioration mediated by multiple factors but is also considered salvageable. Astaxanthin (ATX), which is extracted from some marine organisms, is a natural compound with a strong antioxidant effect that has been reported to attenuate organ injuries caused by traumatic injuries. Hence, we investigated the potential effects of ATX on preventing early burn-wound progression. A classic “comb” burn rat model was established in this study for histological and biological assessments, which revealed that ATX, particularly higher doses, alleviated histological deterioration in the stasis zone. Additionally, we observed dose-dependent improvements in oxidative stress and the release of inflammatory mediators after ATX treatment. Furthermore, ATX dose-dependently attenuated burn-induced apoptosis in the wound areas, and this effect was accompanied by increases in Akt and Bad phosphorylation and a downregulation of cytochrome C and caspase expression. In addition, the administration of Ly 294002 further verified the effect of ATX. In summary, we demonstrated that ATX protected against early burn-wound progression in a rat deep-burn model. This protection might be mediated by the attenuation of oxidative stress-induced inflammation and mitochondria-related apoptosis. PMID:28128352

Low NO sub x heavy fuel combustor concept program

NASA Technical Reports Server (NTRS)

Russell, P.; Beal, G.; Hinton, B.

1981-01-01

A gas turbine technology program to improve and optimize the staged rich lean low NOx combustor concept is described. Subscale combustor tests to develop the design information for optimization of the fuel preparation, rich burn, quick air quench, and lean burn steps of the combustion process were run. The program provides information for the design of high pressure full scale gas turbine combustors capable of providing environmentally clean combustion of minimally of minimally processed and synthetic fuels. It is concluded that liquid fuel atomization and mixing, rich zone stoichiometry, rich zone liner cooling, rich zone residence time, and quench zone stoichiometry are important considerations in the design and scale up of the rich lean combustor.

Co-production of Nitrogen-15 and Oxygen-18 in Explosive Helium Burning and Implications for Supernova Graphite Grains

NASA Astrophysics Data System (ADS)

Bojazi, Michael

My Masters research involves simulations of a supernova whereby a shock wave of constant Mach number is sent through a 15-solar-mass star evolved to the point of core-collapse. The resulting nucleosynthesis is examined with the intent of explaining the overproduction, relative to solar values, of nitrogen-15 and oxygen-18 abundances in supernova presolar graphite grains, as experimentally determined by Groopman et al. via a NanoSIMS analysis. We find such overabundances to be present in the helium-rich zone. Oxygen-18 is leftover from presupernova helium burning while nitrogen-15 is produced by explosive helium burning. Interestingly, anomalous excesses in molybdenum-95 and molybdenum-97 abundances in SiC X grains, discovered by Pellin et al. using the CHARISMA instrument, probably arise from explosive helium burning as well. These results signal the importance of the helium-rich zone for supernova presolar grain growth. We suggest that matter deep from the supernova, which is rich in iron-peak elements, gets injected into the helium-rich zone. Small TiC grains form in this material. These subgrains then traverse the helium-rich zone and serve as seeds for the growth of the graphite or SiC X grains.

Quantifying the fire regime distributions for severity in Yosemite National Park, California, USA

USGS Publications Warehouse

Thode, Andrea E.; van Wagtendonk, Jan W.; Miller, Jay D.; Quinn, James F.

2011-01-01

This paper quantifies current fire severity distributions for 19 different fire-regime types in Yosemite National Park, California, USA. Landsat Thematic Mapper remote sensing data are used to map burn severity for 99 fires (cumulatively over 97 000 ha) that burned in Yosemite over a 20-year period. These maps are used to quantify the frequency distributions of fire severity by fire-regime type. A classification is created for the resultant distributions and they are discussed within the context of four vegetation zones: the foothill shrub and woodland zone; the lower montane forest zone; the upper montane forest zone and the subalpine forest zone. The severity distributions can form a building block from which to discuss current fire regimes across the Sierra Nevada in California. This work establishes a framework for comparing the effects of current fires on our landscapes with our notions of how fires historically burned, and how current fire severity distributions differ from our desired future conditions. As this process is refined, a new set of information will be available to researchers and land managers to help understand how fire regimes have changed from the past and how we might attempt to manage them in the future.

Alternative pathways to landscape transformation: Invasive grasses, burn severity and fire frequency in arid ecosystems

USGS Publications Warehouse

Klinger, Robert C.; Brooks, Matthew L.

2017-01-01

Arid ecosystems are often vulnerable to transformation to invasive-dominated states following fire, but data on persistence of these states are sparse. The grass/fire cycle is a feedback process between invasive annual grasses and fire frequency that often leads to the formation of alternative vegetation states dominated by the invasive grasses. However, other components of fire regimes, such as burn severity, also have the potential to produce long-term vegetation transformations. Our goal was to evaluate the influence of both fire frequency and burn severity on the transformation of woody-dominated communities to communities dominated by invasive grasses in major elevation zones of the Mojave Desert of western North America.We used a chronosequence design to collect data on herbaceous and woody cover at 229 unburned reference plots and 578 plots that burned between 1972 and 2010. We stratified the plots by elevation zone (low, mid, high), fire frequency (1–3 times) and years post-fire (YPF; 1–5, 6–10, 11–20 and 21–40 YPF). Burn severity for each plot was estimated by the difference normalized burn ratio.We identified two broad post-fire successional pathways. One was an outcome of fire frequency, resulting in a strong potential transformation via the grass/fire cycle. The second pathway was driven by burn severity, the critical aspect being that long-term transformation of a community could occur from just one fire in areas that burned at high or sometimes moderate severity. Dominance by invasive grasses was most likely to occur in low-and high-elevation communities; cover of native herbaceous species was often greater than that of invasive grasses in the mid-elevation zone.Synthesis. Invasive grasses can dominate a site that burned only one time in many decades at high severity, or a site that burned at low severity but multiple times in the same time period. However, high burn severity may predispose areas to more frequent fire because they have relatively high cover of invasive annual grass, suggesting burn severity and fire frequency have both independent and synergistic effects. Resilience in vegetation structure following fire in many arid communities may be limited to a narrow window of low burn severity in areas that have not burned in many decades.

In vivo terahertz imaging of rat skin burns

NASA Astrophysics Data System (ADS)

Tewari, Priyamvada; Kealey, Colin P.; Bennett, David B.; Bajwa, Neha; Barnett, Kelli S.; Singh, Rahul S.; Culjat, Martin O.; Stojadinovic, Alexander; Grundfest, Warren S.; Taylor, Zachary D.

2012-04-01

A reflective, pulsed terahertz (THz) imaging system was used to acquire high-resolution (d10-90/ λ~1.925) images of deep, partial thickness burns in a live rat. The rat's abdomen was burned with a brass brand heated to ~220°C and pressed against the skin with contact pressure for ~10 sec. The burn injury was imaged beneath a Mylar window every 15 to 30 min for up to 7 h. Initial images display an increase in local water concentration of the burned skin as evidenced by a marked increase in THz reflectivity, and this likely correlates to the post-injury inflammatory response. After ~1 h the area of increased reflectivity consolidated to the region of skin that had direct contact with the brand. Additionally, a low reflecting ring of tissue could be observed surrounding the highly reflective burned tissue. We hypothesize that these regions of increased and decreased reflectivity correlate to the zones of coagulation and stasis that are the classic foundation of burn wound histopathology. While further investigations are necessary to confirm this hypothesis, if true, it likely represents the first in vivo THz images of these pathologic zones and may represent a significant step forward in clinical application of THz technology.

Condensation and mixing in supernova ejecta

NASA Astrophysics Data System (ADS)

Fedkin, A. V.; Meyer, B. S.; Grossman, L.

2010-06-01

Low-density graphite spherules from the Murchison carbonaceous chondrite contain TiC grains and possess excess 28Si and 44Ca (from decay of short-lived 44Ti). These and other isotopic anomalies indicate that such grains formed by condensation from mixtures of ejecta from the interior of a core-collapse supernova with those from the exterior. Using homogenized chemical and isotopic model compositions of the eight main burning zones as end-members, Travaglio et al. (1999) attempted to find mixtures whose isotopic compositions match those observed in the graphite spherules, subject to the condition that the atomic C/O ratio = 1. They were partially successful, but this chemical condition does not guarantee condensation of TiC at a higher temperature than graphite, which is indicated by the spherule textures. In the present work, model compositions of relatively thin layers of ejecta within the main burning zones computed by Rauscher et al. (2002) for Type II supernovae of 15, 21 and 25 M ʘ are used to construct mixtures whose chemical compositions cause equilibrium condensation of TiC at a higher temperature than graphite in an attempt to match the textures and isotopic compositions of the spherules simultaneously. The variation of pressure with temperature and the change in elemental abundances with time due to radioactive decay were taken into account in the condensation calculations. Layers were found within the main Ni, O/Ne, He/C and He/N zones that, when mixed together, simultaneously match the carbon, nitrogen and oxygen isotopic compositions, 44Ti/ 48Ti ratios and inferred initial 26Al/ 27Al ratios of the low-density graphite spherules, even at subsolar 12C/ 13C ratios. Due to the relatively large proportion of material from the Ni zone and the relative amounts of the two layers of the Ni zone required to meet these conditions, predicted 28Si excesses are larger than observed in the low-density graphite spherules, and large negative δ46Ti/ 48Ti, δ47Ti/ 48Ti, δ49Ti/ 48Ti and δ50Ti/ 48Ti are produced, in contrast to the observed normal δ46Ti/ 48Ti and δ47Ti/ 48Ti, large positive δ49Ti/ 48Ti and smaller positive δ50Ti/ 48Ti. Although better matches to the observed δ46Ti/ 48Ti, δ47Ti/ 48Ti and 28Si excesses can be found using much smaller amounts of Ni zone material and some Si/S zone material, it is very difficult to match simultaneously the Ti and Si isotopic compositions in any mixtures of material from these deep layers with He/C and He/N zone material, regardless of the condensation sequence. The occurrence of Fe-rich, Si-poor metal grains inside the graphite spherules does not have a satisfactory explanation.

Experimental Investigation of Premixed Turbulent Hydrocarbon/Air Bunsen Flames

NASA Astrophysics Data System (ADS)

Tamadonfar, Parsa

Through the influence of turbulence, the front of a premixed turbulent flame is subjected to the motions of eddies that leads to an increase in the flame surface area, and the term flame wrinkling is commonly used to describe it. If it is assumed that the flame front would continue to burn locally unaffected by the stretch, then the total turbulent burning velocity is expected to increase proportionally to the increase in the flame surface area caused by wrinkling. When the turbulence intensity is high enough such that the stretch due to hydrodynamics and flame curvature would influence the local premixed laminar burning velocity, then the actual laminar burning velocity (that is, flamelet consumption velocity) should reflect the influence of stretch. To address this issue, obtaining the knowledge of instantaneous flame front structures, flame brush characteristics, and burning velocities of premixed turbulent flames is necessary. Two axisymmetric Bunsen-type burners were used to produce premixed turbulent flames, and three optical measurement techniques were utilized: Particle image velocimetry to measure the turbulence statistics; Rayleigh scattering method to measure the temperature fields of premixed turbulent flames, and Mie scattering method to visualize the flame front contours of premixed turbulent flames. Three hydrocarbons (methane, ethane, and propane) were used as the fuel in the experiments. The turbulence was generated using different perforated plates mounted upstream of the burner exit. A series of comprehensive parameters including the thermal flame front thickness, characteristic flame height, mean flame brush thickness, mean volume of the turbulent flame region, two-dimensional flame front curvature, local flame front angle, two-dimensional flame surface density, wrinkled flame surface area, turbulent burning velocity, mean flamelet consumption velocity, mean turbulent flame stretch factor, mean turbulent Markstein length and number, and mean fuel consumption rate were systematically evaluated from the experimental data. The normalized preheat zone and reaction zone thicknesses decreased with increasing non-dimensional turbulence intensity in ultra-lean premixed turbulent flames under a constant equivalence ratio of 0.6, whereas they increased with increasing equivalence ratios from 0.6 to 1.0 under a constant bulk flow velocity. The normalized preheat zone and reaction zone thicknesses showed no overall trend with increasing non-dimensional longitudinal integral length scale. The normalized preheat zone and reaction zone thicknesses decreased by increasing the Karlovitz number, suggesting that increasing the total stretch rate is the controlling mechanism in the reduction of flame front thickness for the experimental conditions studied in this thesis. In general, the leading edge and half-burning surface turbulent burning velocities were enhanced with increasing equivalence ratio from lean to stoichiometric mixtures, whereas they decreased with increasing equivalence ratio for rich mixtures. These velocities were enhanced with increasing total turbulence intensity. The leading edge and half-burning surface turbulent burning velocities for lean/stoichiometric mixtures were observed to be smaller than that for rich mixtures. The mean turbulent flame stretch factor displayed a dependence on the equivalence ratio and turbulence intensity. Results show that the mean turbulent flame stretch factors for lean/stoichiometric and rich mixtures were not equal when the unstrained premixed laminar burning velocity, non-dimensional bulk flow velocity, non-dimensional turbulence intensity, and non-dimensional longitudinal integral length scale were kept constant.

Constraints on CEMP-no progenitors from nuclear astrophysics

NASA Astrophysics Data System (ADS)

Choplin, Arthur; Maeder, André; Meynet, Georges; Chiappini, Cristina

2016-09-01

Context. The CEMP-no stars are long-lived small mass stars presenting a very low iron content and overabundances of carbon with no sign or only very weak signs of s- or r-elements. Although the origin of this abundance pattern is still a matter of debate, it was very likely inherited from a previous massive star, which we call the source star. Aims: We rely on a recent classification of CEMP-no stars arguing that some of them are made of a material processed by hydrogen burning that was enriched in products of helium burning during the nuclear life of the source star. We examine the possibility of forming CEMP-no stars with this material. Methods: We study the nucleosynthesis of the CNO cycle and the Ne-Na Mg-Al chains in a hydrogen burning single zone while injecting the helium burning products 12C, 16O, 22Ne, and 26Mg. We investigate the impact of changing density, temperature and the injection rate. The nuclear reaction rates involving the creation and destruction of 27Al are also examined. Results: 14N, 23Na, 24Mg, and 27Al are formed when injecting 12C, 16O, 22Ne, and 26Mg in the hydrogen burning zone. The 12C/13C ratio is constant under various conditions in the hydrogen burning zone. The predicted [Al/Fe] ratio varies up to ~ 2 dex depending on the prescription used for the reaction rates involving 27Al. Conclusions: The experiments we carried out support the view that some CEMP-no stars are made of a material processed by hydrogen burning that comes from a massive star experiencing mild to strong rotational mixing. During its burning, this material was likely enriched in helium burning products. No material coming from the carbon-oxygen rich core of the source star should be added to form the daughter star, otherwise the 12C/13C ratio would be largely above the observed range of values.

Soil microbial abundance, activity and diversity response in two different altitude-adapted plant communities affected by wildfire in Sierra Nevada National Park (Granada, Spain)

NASA Astrophysics Data System (ADS)

Bárcenas-Moreno, Gema; Zavala, Lorena; Jordan, Antonio; Bååth, Erland; Mataix-Beneyto, Jorge

2013-04-01

Plant communities can play an important role in fire severity and post-fire ecosystem recovery due to their role as combustible and different plant-soil microorganisms interactions. Possible differences induced by plant and microorganisms response after fire could affect the general ecosystem short and long-term response and its sustainability. The main objective of this work was the evaluation of the effect of wildfire on soil microbial abundance, activity and diversity in two different plant communities associated to different altitudes in Sierra Nevada National Park (Granada, Spain). Samples were collected in two areas located on the Sierra Nevada Mountain between 1700 and 2000 m above sea level which were affected by a large wildfire in 2005. Two samplings were carried out 8 and 20 months after fire and samples were collected in both burned and unburned (control) zones in each plant community area. Area A is located at 1700m and it is formed by Quercus rotundifolia forest while area B is located at 2000 m altitude and is composed of alpine vegetation formed by creeping bearing shrubs. Microbial biomass measured by Fumigation-Extraction method followed the same trend in both areas showing slight and no significant differences between burned and unburned area during the study period while viable and cultivable bacteria abundance were markedly higher in fire affected samples than in the control ones in both samplings. Viable and cultivable filamentous fungi had different behavior depending of plant vegetation community studied showing no differences between burned and unburned area in area A while was significantly higher in burned samples than in the control ones in area B. Microbial activity monitoring with soil microbial respiration appears to had been affected immediately after fire since microbial respiration was lower in burned samples from area A than in unburned one only 8 months after fire and no significant differences were observed between burned and unburned samples in area B. Soil microbial community composition studied by Principal Component Analyses (PCA) of the PLFA pattern revealed both fire and seasonal effects. General overview of the results could lead to think in a slight negative or even positive effect of fire on soil microbial parameters studied, mainly in zone B. Nevertheless if we calculate the ratio between C-biomass and organic-C we find lower ratio in fire-affected samples than in the control ones in both areas, showing the most marked effect on area B which remain with this tendency 20 months after fire. Acknowledgements: This research was supported by the CICYT co-financed FEDER project CGL2006-11107-C02-01/BOS. We are grateful for the Sierra Nevada National Park support during the study.

Radiative effects of biomass burning aerosols and cloudiness on seasonal carbon cycle in the Amazon region

NASA Astrophysics Data System (ADS)

Moreira, D. S.; Longo, K.; Freitas, S.; Mercado, L. M.; Miller, J. B.; Rosario, N. M. E. D.; Gatti, L.; Yamasoe, M. A.

2017-12-01

The Amazon region is characterized by high cloudiness, mainly due to convective clouds during most of the year due to the high humidity, and heat availability. However, during the Austral winter, the northward movement of the inter-tropical convergence zone (ITCZ) from its climatological position, significantly reducing cloudiness and precipitation, facilitating vegetation fires. Consequently, during these dry months, biomass burning aerosols contribute to relatively high values of aerosol optical depth (AOD) in Amazonia, typically exceeding 1.0 in the 550 nm wavelength. Both clouds and aerosols scatter solar radiation, reducing the direct irradiance and increasing the diffuse fraction that reaches the surface, decreasing near surface temperature and increasing photosynthetically active radiation (PAR) availability. This, in turn, affects energy and CO2 fluxes within the vegetation canopy. We applied an atmospheric model fully coupled to terrestrial carbon cycle model to assess the relative impact of biomass burning aerosols and clouds on CO2 fluxes in the Amazon region. Our results indicate that during most of the year, gross primary productivity (GPP) is high mainly due to high soil moisture and high values of the diffuse fraction of solar irradiation due to cloudiness. Therefore, heterotrophic and autotrophic respiration are both high, increasing the NEE values (i.e. reducing the net land sink). On the other hand, during the dry season, with a significant reduction of cloudiness, the biomass burning aerosol is mainly responsible for the increase in the diffuse fraction of solar irradiation and the GPP of the forest. However, the low soil moisture during the dry season, especially in the eastern Amazon, reduces heterotrophic and autotrophic respiration and thus compensates for reduced GPP compared to the wet season. Different reasons, an anthropogenic one (human induced fires during the dry season) and a natural one (cloudiness), lead to a somewhat stable value of NEE all year long in Amazonia.

Combustion chamber and thermal vapor stream producing apparatus and method

DOEpatents

Sperry, John S.; Krajicek, Richard W.; Cradeur, Robert R.

1978-01-01

A new and improved method and apparatus for burning a hydrocarbon fuel for producing a high pressure thermal vapor stream comprising steam and combustion gases for injecting into a subterranean formation for the recovery of liquefiable minerals therefrom, wherein a high pressure combustion chamber having multiple refractory lined combustion zones of varying diameters is provided for burning a hydrocarbon fuel and pressurized air in predetermined ratios injected into the chamber for producing hot combustion gases essentially free of oxidizing components and solid carbonaceous particles. The combustion zones are formed by zones of increasing diameters up a final zone of decreasing diameter to provide expansion zones which cause turbulence through controlled thorough mixing of the air and fuel to facilitate complete combustion. The high pressure air and fuel is injected into the first of the multiple zones where ignition occurs with a portion of the air injected at or near the point of ignition to further provide turbulence and more complete combustion.

Climate change and wildfire around southern Africa

NASA Astrophysics Data System (ADS)

Kimura, K.

2013-12-01

When the climate change in southern Africa is analyzed, the effects of rainfall by Inter Tropical Convergence Zone(ITCZ) and cyclone are important. In this study, the rainfall patterns are analyzed with synoptic analysis. The southern limit of ITCZ is around the arid zone around Namibia, Botswana, Zimbabwe and Mozambique. This zone has some effects of both ITCZ and extratropical cyclones by season. As well as this, the eastern part of this area has heavy rainfall by the cyclone from the Indian Ocean once in several years. In the other hand, a lot of wildfire occurs in this area. The main cause of the wildfire is anthropogenic misbehavior of the fire by the slash-and-burn agriculture. Recently we can find the wildfire detected with the satellite imagery like Terra/Aqua MODIS. We can compare the weather environment and the wildfire occurrence with Geographical Information System. We have tried making the fire weather index suitable for the southern African semi-arid area.

Magnetic braking of stellar cores in red giants and supergiants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maeder, André; Meynet, Georges, E-mail: andre.maeder@unige, E-mail: georges.meynet@unige.ch

2014-10-01

Magnetic configurations, stable on the long term, appear to exist in various evolutionary phases, from main-sequence stars to white dwarfs and neutron stars. The large-scale ordered nature of these fields, often approximately dipolar, and their scaling according to the flux conservation scenario favor a fossil field model. We make some first estimates of the magnetic coupling between the stellar cores and the outer layers in red giants and supergiants. Analytical expressions of the truncation radius of the field coupling are established for a convective envelope and for a rotating radiative zone with horizontal turbulence. The timescales of the internal exchangesmore » of angular momentum are considered. Numerical estimates are made on the basis of recent model grids. The direct magnetic coupling of the core to the extended convective envelope of red giants and supergiants appears unlikely. However, we find that the intermediate radiative zone is fully coupled to the core during the He-burning and later phases. This coupling is able to produce a strong spin down of the core of red giants and supergiants, also leading to relatively slowly rotating stellar remnants such as white dwarfs and pulsars. Some angular momentum is also transferred to the outer convective envelope of red giants and supergiants during the He-burning phase and later.« less

Distribution, Transport, and Accumulation of Pyrogenic Black Carbon in Post-Wildfire Watersheds

NASA Astrophysics Data System (ADS)

Galanter, A.; Cadol, D. D.; Frey, B.; Lohse, K. A.

2014-12-01

Large, high severity wildfires greatly alter forest structure, water quality, and soil development/erosion. With increased frequency of such wildfires also follows heavy post-wildfire debris flows and flooding which deliver high loads of sediment and pyrogenic black carbon (PyC) to downstream waterways. The accumulation of PyC is a multi-faceted and dynamic issue in the critical zone. Generated by incomplete combustion of organic matter, PyC (in the form of soot and char) impacts turbidity, biological and chemical oxygen demand, and pH. In addition, PyC has the potential to sequester contaminants and can store carbon over short and long timescales. The impacts of two recent wildfires in Northern New Mexico are studied with the goal of understanding the fluxes and residence times of PyC in post-wildfire, mountainous watersheds. Employing burn severity maps and geospatial data, we selected three sites to collect soil and water samples to characterize PyC: a control, an area impacted by a large, severe burn (2011), and an area impacted by a smaller, less severe burn (2013). By collaborating with researchers at the Jemez Critical Zone Observatory, soil samples are being analyzed and will provide pre-wildfire PyC concentrations for the 2013 burn area. In this study, PyC is treated as both a particulate and a solute that is transported throughout the watershed as well as degraded in soils, surface water and groundwater. We used two black carbon quantification methods: the chemo-thermal oxidation (CTO-375) method to distinguish between soil soot and char, and the benzene polycarboxylic acids (BPCA) method to quantify the total concentrations of PyC in soil and water samples. Preliminary soil data from the CTO-375 method show comparable soot concentrations in the control, 2011, and 2013 burn indicating that the soot is more recalcitrant than char and remains in the watershed long after a wildfire. This data also suggests that the fluxes of black carbon over short time scales are composed mainly of char.

Common Occurrence of Explosive Hydrogen Burning in Type II Supernovae

NASA Astrophysics Data System (ADS)

Liu, Nan; Stephan, Thomas; Boehnke, Patrick; Nittler, Larry R.; Meyer, Bradley S.; O’D. Alexander, Conel M.; Davis, Andrew M.; Trappitsch, Reto; Pellin, Michael J.

2018-03-01

We report Mo isotopic data for 16 15N-rich presolar SiC grains of type AB (14N/15N < solar, AB1) and their correlated Sr and Ba isotope ratios when available. Of the 16 AB1 grains, 8 show s-process Mo isotopic compositions, together with s-process Ba and/or Sr isotopic compositions. We found that a higher percentage of AB1 grains show anomalous isotopic compositions than that of AB2 grains (14N/15N > solar), thus providing further support to the division of the two AB subgroups recently proposed by Liu et al., who showed that AB1 grains most likely originated from Type II supernovae (SNe) with explosive H burning. Comparison of the Sr, Mo, and Ba isotopic compositions of the AB1 grains with SN model predictions indicates that the s-process isotopic compositions of AB1 grains resulted from neutron-capture processes occurring during the progenitor massive stars’ pre-SN evolution rather than from an explosive neutron-capture process. In addition, the observations of (1) explosive H burning occurring in the C-rich regions of the progenitor SNe of X grains as suggested by the isotopic compositions of X grains, and (2) explosive H burning occurring both at the bottom of the He/C zone and at the top of the He/N zone as suggested by model simulations, imply that explosive H burning is a common phenomenon in outer SN zones.

Common Occurrence of Explosive Hydrogen Burning in Type II Supernovae

DOE PAGES

Liu, Nan; Stephan, Thomas; Boehnke, Patrick; ...

2018-03-16

In this paper, we report Mo isotopic data for 16 15N-rich presolar SiC grains of type AB ( 14N/ 15N < solar, AB1) and their correlated Sr and Ba isotope ratios when available. Of the 16 AB1 grains, 8 show s-process Mo isotopic compositions, together with s-process Ba and/or Sr isotopic compositions. We found that a higher percentage of AB1 grains show anomalous isotopic compositions than that of AB2 grains ( 14N/ 15N > solar), thus providing further support to the division of the two AB subgroups recently proposed by Liu et al., who showed that AB1 grains most likelymore » originated from Type II supernovae (SNe) with explosive H burning. Comparison of the Sr, Mo, and Ba isotopic compositions of the AB1 grains with SN model predictions indicates that the s-process isotopic compositions of AB1 grains resulted from neutron-capture processes occurring during the progenitor massive stars' pre-SN evolution rather than from an explosive neutron-capture process. Finally, in addition, the observations of (1) explosive H burning occurring in the C-rich regions of the progenitor SNe of X grains as suggested by the isotopic compositions of X grains, and (2) explosive H burning occurring both at the bottom of the He/C zone and at the top of the He/N zone as suggested by model simulations, imply that explosive H burning is a common phenomenon in outer SN zones.« less

Common Occurrence of Explosive Hydrogen Burning in Type II Supernovae

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Nan; Stephan, Thomas; Boehnke, Patrick

In this paper, we report Mo isotopic data for 16 15N-rich presolar SiC grains of type AB ( 14N/ 15N < solar, AB1) and their correlated Sr and Ba isotope ratios when available. Of the 16 AB1 grains, 8 show s-process Mo isotopic compositions, together with s-process Ba and/or Sr isotopic compositions. We found that a higher percentage of AB1 grains show anomalous isotopic compositions than that of AB2 grains ( 14N/ 15N > solar), thus providing further support to the division of the two AB subgroups recently proposed by Liu et al., who showed that AB1 grains most likelymore » originated from Type II supernovae (SNe) with explosive H burning. Comparison of the Sr, Mo, and Ba isotopic compositions of the AB1 grains with SN model predictions indicates that the s-process isotopic compositions of AB1 grains resulted from neutron-capture processes occurring during the progenitor massive stars' pre-SN evolution rather than from an explosive neutron-capture process. Finally, in addition, the observations of (1) explosive H burning occurring in the C-rich regions of the progenitor SNe of X grains as suggested by the isotopic compositions of X grains, and (2) explosive H burning occurring both at the bottom of the He/C zone and at the top of the He/N zone as suggested by model simulations, imply that explosive H burning is a common phenomenon in outer SN zones.« less

Rich burn combustor technology at Pratt and Whitney

NASA Technical Reports Server (NTRS)

Lohmann, Robert P.; Rosfjord, T. J.

1992-01-01

The topics covered include the following: near term objectives; rich burn quick quench combustor (RBQC); RBQC critical technology areas; cylindrical RBQQ combustor rig; modular RBQQ combustor; cylindrical rig objectives; quench zone mixing; noneffusive cooled liner; variable geometry requirements; and sector combustor rig.

76 FR 31583 - Reorganization of Foreign-Trade Zone 152, (Expansion of Service Area) Under Alternative Site...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-01

... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Order No. 1763] Reorganization of Foreign-Trade Zone 152, (Expansion of Service Area) Under Alternative Site Framework, Burns Harbor, IN Pursuant to its authority under the Foreign-Trade Zones Act of June 18, 1934, as amended (19 U.S.C. 81a-81u), the...

Component testing of a ground based gas turbine steam cooled rich-burn primary zone combustor for emissions control of nitrogeneous fuels

NASA Technical Reports Server (NTRS)

Schultz, D. F.

1986-01-01

This effort summarizes the work performed on a steam cooled, rich-burn primary zone, variable geometry combustor designed for combustion of nitrogeneous fuels such as heavy oils or synthetic crude oils. The steam cooling was employed to determine its feasibility and assess its usefulness as part of a ground based gas turbine bottoming cycle. Variable combustor geometry was employed to demonstrate its ability to control primary and secondary zone equivalence ratios and overall pressure drop. Both concepts proved to be highly successful in achieving their desired objectives. The steam cooling reduced peak liner temperatures to less than 800 K. This low temperature offers the potential of both long life and reduced use of strategic materials for liner fabrication. These degrees of variable geometry were successfully employed to control air flow distribution within the combustor. A variable blade angle axial flow air swirler was used to control primary zone air flow, while the secondary and tertiary zone air flows were controlled by rotating bands which regulated air flow to the secondary zone quench holes and the dilutions holes respectively.

Testing the shorter and variable recurrence interval hypothesis along the Cholame segment of the San Andreas Fault

NASA Astrophysics Data System (ADS)

Williams, A.; Arrowsmith, R.; Rockwell, T. K.; Akciz, S. O.; Grant Ludwig, L.

2016-12-01

The Cholame segment of the San Andreas Fault interacts with the Parkfield segment to the northwest with its creep and M6 earthquakes and the locked Carrizo segment to the southeast. Although offset reconstructions exist for this 75 km reach, rupture behavior is poorly characterized, limiting seismic hazard evaluation. Here we present new paleoseismic results from 2 fault perpendicular 26 m long trenches connected by a 15 m long fault parallel trench. The site is located south of the Parkfield segment 20 km southeast of Highway 46. Site geomorphology is characterized by several 50 m offset drainages northwest of the trenches, small shutter ridges and sag ponds, and alluvial fans crossing the fault. Fault zone stratigraphy consists of alternating finely bedded sands, silts, and gravels, and bioturbated soil horizons. The strata record 3-4 earthquakes and possible deformation post-1857, similar to the LY4 site 38 km southeast. E4, E3 and the most recent earthquake (MRE) are well supported by evidence of decreasing vertical offset up-sequence, capped fissure fill and colluvial wedges, which create small horst and graben structures. Units display vertical offsets ranging from 60 cm at the base to 12 cm near the MRE horizon, small colluvial wedges, and sag deposits within the 4 m wide fault zone. E2—the penultimate-is less certain, supported only by the decreasing offset in the stratigraphic sequence. The E4 event horizon is a gradational clayey silt sag deposit capped by discontinuous gravel, 18 cm at its thickest point and extending 4.8 m across the fault zone. The E3 and E2 event horizons are capped by thin bedded silty clay, and bounded by discontinuous burn horizons. The MRE horizon extends 6 m across the main fault zone, and consists of a silty clay sag deposit capped by very fine, bedded sand and coarse gravel, 22 cm at its thickest point and overlying a burn horizon. If the MRE is indeed the 1857 event, it has significant potential in correlation with the high quality rupture records at Bidart (70 km southeast), and Frazier Mountain (180 km southeast). This site contains abundant detrital charcoal in many of the units and burn horizons at or near event horizons providing great potential for bracketing the age of these paleoearthquakes.

78 FR 38200 - Safety Zones; Annual Independence Day Fireworks Displays, Skagway, Haines, and Wrangell, AK

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-26

..., darkness punctuated by bright flashes of light, and burning debris has the potential to result in serious... enforcement of these safety zones will be of short duration, approximately three hours. Furthermore, vessels...

Improving work-zone delineation on limited access highways.

DOT National Transportation Integrated Search

1989-01-01

The purpose of this study was to investigate vehicle guidance through work zones by evaluating the effectiveness of two primary components of traffic control relative to delineation. First, a comparison of the steady-burn lights presently used on top...

HERMES: A Model to Describe Deformation, Burning, Explosion, and Detonation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reaugh, J E

2011-11-22

HERMES (High Explosive Response to MEchanical Stimulus) was developed to fill the need for a model to describe an explosive response of the type described as BVR (Burn to Violent Response) or HEVR (High Explosive Violent Response). Characteristically this response leaves a substantial amount of explosive unconsumed, the time to reaction is long, and the peak pressure developed is low. In contrast, detonations characteristically consume all explosive present, the time to reaction is short, and peak pressures are high. However, most of the previous models to describe explosive response were models for detonation. The earliest models to describe the responsemore » of explosives to mechanical stimulus in computer simulations were applied to intentional detonation (performance) of nearly ideal explosives. In this case, an ideal explosive is one with a vanishingly small reaction zone. A detonation is supersonic with respect to the undetonated explosive (reactant). The reactant cannot respond to the pressure of the detonation before the detonation front arrives, so the precise compressibility of the reactant does not matter. Further, the mesh sizes that were practical for the computer resources then available were large with respect to the reaction zone. As a result, methods then used to model detonations, known as {beta}-burn or program burn, were not intended to resolve the structure of the reaction zone. Instead, these methods spread the detonation front over a few finite-difference zones, in the same spirit that artificial viscosity is used to spread the shock front in inert materials over a few finite-difference zones. These methods are still widely used when the structure of the reaction zone and the build-up to detonation are unimportant. Later detonation models resolved the reaction zone. These models were applied both to performance, particularly as it is affected by the size of the charge, and to situations in which the stimulus was less than that needed for reliable performance, whether as a result of accident, hazard, or a fault in the detonation train. These models describe the build-up of detonation from a shock stimulus. They are generally consistent with the mesoscale picture of ignition at many small defects in the plane of the shock front and the growth of the resulting hot-spots, leading to detonation in heterogeneous explosives such as plastic-bonded explosives (PBX). The models included terms for ignition, and also for the growth of reaction as tracked by the local mass fraction of product gas, {lambda}. The growth of reaction in such models incorporates a form factor that describes the change of surface area per unit volume (specific surface area) as the reaction progresses. For unimolecular crystalline-based explosives, the form factor is consistent with the mesoscale picture of a galaxy of hot spots burning outward and eventually interacting with each other. For composite explosives and propellants, where the fuel and oxidizer are segregated, the diffusion flame at the fuel-oxidizer interface can be interpreted with a different form factor that corresponds to grains burning inward from their surfaces. The form factor influences the energy release rate, and the amount of energy released in the reaction zone. Since the 19th century, gun and cannon propellants have used perforated geometric shapes that produce an increasing surface area as the propellant burns. This helps maintain the pressure as burning continues while the projectile travels down the barrel, which thereby increases the volume of the hot gas. Interior ballistics calculations use a geometric form factor to describe the changing surface area precisely. As a result, with a suitably modified form factor, detonation models can represent burning and explosion in damaged and broken reactant. The disadvantage of such models in application to accidents is that the ignition term does not distinguish between a value of pressure that results from a shock, and the same pressure that results from a more gradual increase. This disagrees with experiments, where explosives were subjected to a gradual rise in pressure and did not exhibit reaction. More recent models do distinguish between slow pressure rises and shocks, and have had some success in the describing the response of explosives to single and multiple shocks, and the increase of shock sensitivity with porosity, at least over a limited range. The original formulation is appropriate for sustained shocks, but further work is ongoing to describe the response to short pulses. The HERMES model combines features from these prior models. It describes burning and explosion in damaged reactant, and also will develop a detonation if the gradual rise in pressure from burning steepens into a strong-enough shock. The shock strength needed for detonation in a fixed run distance decreases with increasing porosity.« less

Rapid and selective enzymatic debridement of porcine comb burns with bromelain-derived Debrase: acute-phase preservation of noninjured tissue and zone of stasis.

PubMed

Singer, Adam J; McClain, Steve A; Taira, Breena R; Rooney, Jean; Steinhauff, Nicole; Rosenberg, Lior

2010-01-01

Deep burns are associated with the formation of an eschar, which delays healing and increases the risk of infection. Surgical debridement of the eschar is, at present, the fastest means to achieve an eschar-free bed, but the process can not differentiate between the viable tissue and the eschar and follow the minute irregularities of the interface between the two. We evaluated the efficacy and selectivity of a novel enzymatic bromelain-based debriding agent, Debrase Gel Dressing (Debrase), in a porcine comb burn model. We hypothesized that Debrase would result in rapid debridement of the eschar without adverse effects on the surrounding uninjured skin. This is a prospective, controlled, animal experiment. Five domestic pigs (20-25 kg) were used in this study. Sixteen burns were created on each animal's dorsum using a brass comb with four rectangular prongs preheated in boiling water and applied for 30 seconds, resulting in four rectangular 10 x 20 mm full-thickness burns and separated by three 5 x 20 mm unburned interspaces representing the zone of stasis. The burned keratin layer (blisters) was removed, and the burns were treated with a single, topical, Debrase or control vehicle application for 4 hours. The Debrase/control was then wiped off using a metal forceps handle, and the burns were treated with a topical silver sulfadiazine (SSD). The wounds were observed, and full-thickness biopsies were obtained at 4 and 48 hours for evidence of dermal thickness, vascular thrombosis, and burn depth, both within the comb burns and the unburned interspaces in between them. Chi-square and t tests are used for data analysis. A single 4-hour topical application of Debrase resulted in rapid and complete eschar dissolution of all the burns in which the keratin layer was removed. The remaining dermis was thinner (1.1 +/- 0.7 mm) than in the control burns (2.1 +/- 0.3 mm; difference 0.9 mm [95% confidence interval: 0.3-1.4]) and was viable with no injury to the normal surrounding skin or to the unburned interspaces between the burns, which represents the zone of stasis. In control burns, the entire thickness of the dermis was necrotic. At 48 hours, Debrase-treated areas were found partially desiccated under SSD treatment. The unburned interspaces demonstrated partial-thickness necrosis in two third and full-thickness necrosis in one third of wounds. In contrast, full-thickness necrosis was noted in all control interspaces (P = .05). In a porcine comb burn model, a single, 4-hour topical application of Debrase resulted in rapid removal of the necrotic layer of the dermis with preservation of unburned tissues. At 48 hours, SSD treatment resulted in superficial tissue damage and partial preservation of the unburned interspaces.

Quantifying the effects of wildfire on changes in soil properties by surface burning of soils from the Boulder Creek Critical Zone Observatory

USGS Publications Warehouse

Wieting, Celeste; Ebel, Brian A.; Singha, Kamini

2017-01-01

Study regionThis study used intact soil cores collected at the Boulder Creek Critical Zone Observatory near Boulder, Colorado, USA to explore fire impacts on soil properties.Study focusThree soil scenarios were considered: unburned control soils, and low- and high-temperature burned soils. We explored simulated fire impacts on field-saturated hydraulic conductivity, dry bulk density, total organic carbon, and infiltration processes during rainfall simulations.New hydrological insights for the regionSoils burned to high temperatures became more homogeneous with depth with respect to total organic carbon and bulk density, suggesting reductions in near-surface porosity. Organic matter decreased significantly with increasing soil temperature. Tension infiltration experiments suggested a decrease in infiltration rates from unburned to low-temperature burned soils, and an increase in infiltration rates in high-temperature burned soils. Non-parametric statistical tests showed that field-saturated hydraulic conductivity similarly decreased from unburned to low-temperature burned soils, and then increased with high-temperature burned soils. We interpret these changes result from the combustion of surface and near-surface organic materials, enabling water to infiltrate directly into soil instead of being stored in the litter and duff layer at the surface. Together, these results indicate that fire-induced changes in soil properties from low temperatures were not as drastic as high temperatures, but that reductions in surface soil water repellency in high temperatures may increase infiltration relative to low temperatures.

Stellar evolution of high mass based on the Ledoux criterion for convection

NASA Technical Reports Server (NTRS)

Stothers, R.; Chin, C.

1972-01-01

Theoretical evolutionary sequences of models for stars of 15 and 30 solar masses were computed from the zero-age main sequence to the end of core helium burning. During the earliest stages of core helium depletion, the envelope rapidly expands into the red-supergiant configuration. At 15 solar mass, a blue loop on the H-R diagram ensues if the initial metals abundance, initial helium abundance, or C-12 + alpha particle reaction rate is sufficiently large, or if the 3-alpha reaction rate is sufficiently small. These quantities affect the opacity of the base of the outer convection zone, the mass of the core, and the thermal properties of the core. The blue loop occurs abruptly and fully developed when the critical value of any of these quantities is exceeded, and the effective temperature range and fraction of the lifetime of core helium burning during the slow phase of the blue loop vary surprisingly little. At 30 solar mass no blue loop occurs for any reasonable set of input parameters.

Analysis of solid propellant combustion in a closed vessel including secondary reaction

NASA Technical Reports Server (NTRS)

Benreuven, M.; Summerfield, M.

1980-01-01

A theory for combustion of solid propellants in a closed vessel is presented allowing for residual exothermic chemical reaction in the bulk of the gas in the vessel. Particular attention is given to propellants exhibiting thick gaseous flame zones such as nitrocellulose, double-base and nitramine propellants. For these, the reaction at high pressures is assumed to involve mainly the oxidation of residual hydrocarbons by NO. It is shown that the direct dynamic coupling between the exothermicity, the molecular weight reduction and the changing pressure can influence the dp/dt-p traces obtained, in a manner not directly related to mass burning rate of the solid. Energy and species conservation equations are derived for the bulk of the vessel in differential form; the system is solved numerically. The results show the effect of extended chemical reaction upon measurable combustion characteristics such as dp/dt-p and burn rate pressure exponent, demonstrating its potential importance in interpretation of closed vessel firing data, depending on the pace of the residual gas phase reactions.

78 FR 29094 - Safety Zone; Coronado Fourth of July Fireworks, Glorietta Bay; Coronado, CA

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-17

... waterways, darkness punctuated by bright flashes of light and burning debris has the potential to result in...: The safety zone will only be in effect for one hour, late in the evening when vessel traffic is low...

Early effects of forest fire on streamflow characteristics.

Treesearch

H.W. Berndt

1971-01-01

A comparison of streamflow records from three small mountain streams in north-central Washington before, during, and after a severe forest fire showed three immediate effects of destructive burning. These were: 1. Flow rate was greatly reduced while the fire was actively burning. 2. Destruction of vegetation in the riparian zone reduced...

Modelling of pore coarsening in the high burn-up structure of UO2 fuel

NASA Astrophysics Data System (ADS)

Veshchunov, M. S.; Tarasov, V. I.

2017-05-01

The model for coalescence of randomly distributed immobile pores owing to their growth and impingement, applied by the authors earlier to consideration of the porosity evolution in the high burn-up structure (HBS) at the UO2 fuel pellet periphery (rim zone), was further developed and validated. Predictions of the original model, taking into consideration only binary impingements of growing immobile pores, qualitatively correctly describe the decrease of the pore number density with the increase of the fractional porosity, however notably underestimate the coalescence rate at high burn-ups attained in the outmost region of the rim zone. In order to overcome this discrepancy, the next approximation of the model taking into consideration triple impingements of growing pores was developed. The advanced model provides a reasonable consent with experimental data, thus demonstrating the validity of the proposed pore coarsening mechanism in the HBS.

Using Multitemporal and Multispectral Airborne Lidar to Assess Depth of Peat Loss and Correspondence With a New Active Normalized Burn Ratio for Wildfires

NASA Astrophysics Data System (ADS)

Chasmer, L. E.; Hopkinson, C. D.; Petrone, R. M.; Sitar, M.

2017-12-01

Accuracy of depth of burn (an indicator of consumption) in peatland soils using prefire and postfire airborne light detection and ranging (lidar) data is determined within a wetland-upland forest environment near Fort McMurray, Alberta, Canada. The relationship between peat soil burn depth and an "active" normalized burn ratio (ANBR) is also examined beneath partially and fully burned forest and understory canopies using state-of-the-art active reflectance from a multispectral lidar compared with normalized burn ratio (NBR) derived from Landsat 7 ETM+. We find significant correspondence between depth of burn, lidar-derived ANBR, and difference NBR (dNBR) from Landsat. However, low-resolution optical imagery excludes peatland burn losses in transition zones, which are highly sensitive to peat loss via combustion. The findings presented here illustrate the utility of this new remote sensing technology for expanding an area of research where it has previously been challenging to spatially detect and quantify such wildfire burn losses.

Ground Penetrating Radar, a Method for Exploration and Monitoring of Coal Fires in China

NASA Astrophysics Data System (ADS)

Gundelach, Volker

2010-05-01

Due to the climate change it is a global task to fight against gas emission of coal fires. In China exists many burning coal seams which should be extinguished. A Chinese-German initiative tries to find new technologies and solutions to control these fires. Most of the fires are close to the surface in arid areas. In that case GPR is a possible geophysical method to get detailed information about the structure of the soil. Mining activities and the burning coal are leaving voids which collapse or still exist as dangerous areas. With GPR it is possible to detect voids and clefts. Crevices are potential paths for oxygen transport from the surface to the fire. The knowledge of these structures would help to extinguish the fire. The heat of the burning coal changes the permittivity and the conductivity of the rock. This affects the radar signal and makes it possible to separate burning zones from intact zones. Monitoring of the burning zones helps to find optimal solutions for fire extinguishing strategies. Several field campaigns were made in China. One campaign was in the province Xinjiang with a 50 MHz system from Mala on a steep dipping coal seam. Other campaigns were in the Inner Mongolia with 40 MHz to 200 MHz antennae from GSSI on shallow dipping coal seams. The experiences from these measurements will be shown. The surveys were collected in rough terrain. The data from the unshielded antennae contained a lot of effects coming through the air. The limits of detecting crevices with GPR will be demonstrated. Some parts of the measurements over burning coal were influenced by strong anomalies of the magnetization. Modeling of the radar signal helps at the interpretation. Parts of the interpretation from the surveys can be validated by the outcrop of the investigated structures. A spatial visualization of the results is the basis for discussions.

Fluid Chemistry Dynamics Before and After Fire in the Jemez River Basin Critical Zone Observatory

NASA Astrophysics Data System (ADS)

Chorover, J.; Perdrial, J. N.; Field, J. P.; Pelletier, J. D.; Pohlmann, M. A.; Losleben, M. V.; Lasharr, K.; Amistadi, M.; Brooks, P. D.; McIntosh, J. C.; Meixner, T.; Gallery, R.; Rich, V. I.; Rasmussen, C.; Schaap, M. G.; Breshears, D. D.

2013-12-01

The largest wildfire in New Mexico state history (prior to the Whitewater-Baldy fire of 2012) burned the eastern portion of the Jemez River Basin Critical Zone Observatory (JRB CZO) in June-July 2011. This Los Conchas fire burned large stands of ponderosa pine and mixed conifer (MC) forest within the East Fork Jemez River watershed generating massive post-fire erosion. We asked the question: What are the implications of wildfire on pulsed carbon and other bio-active element redistributions in impacted soils and catchments? As soon as possible following the fire, our research group installed sensor and sampler instrumentation in soil profiles in an intensively burned zero order basin (ZOB), enabling the initiation of comparisons to a similarly instrumented, unburned MC ZOB. The signal of biomass combustion was propagated through soil and stream. Post-burn solute fluxes were dominated by highly-aromatic character DOM, as well as elevated DIC, sulfate, chloride and non-hydrolyzing cation (Ca, Mg, K) concentrations deriving from biomass combustion. Supporting an apparent trend of increasing wildfire in western montane forests, the Thompson Ridge wildfire burned MC forest throughout much of the western previously unburned portion of the Valles Caldera National Preserve in June 2013, including the (until then) "unburned" MC ZOB sites comprising CZO sensor and sampler network arrays. Post-burn soil samples were collected for geochemical, physical, and microbial composition characterizations. Solute and gas fluxes were monitored in situ to compare CZ response following this high intensity burn to three years of pre-burn data. Results indicate that the post-fire pulse of water soluble, biomass-derived ions and carbon into underlying and downslope soils is generating landscape-scale element distribution that could affect recolonization by biota in the ensuing secondary succession.

Burn me twice, shame on who? Interactions between successive forest fires across a temperate mountain region.

PubMed

Harvey, Brian J; Donato, Daniel C; Turner, Monica G

2016-09-01

Increasing rates of natural disturbances under a warming climate raise important questions about how multiple disturbances interact. Escalating wildfire activity in recent decades has resulted in some forests re-burning in short succession, but how the severity of one wildfire affects that of a subsequent wildfire is not fully understood. We used a field-validated, satellite-derived, burn-severity atlas to assess interactions between successive wildfires across the US Northern Rocky Mountains a 300,000-km 2 region dominated by fire-prone forests. In areas that experienced two wildfires between 1984 and 2010, we asked: (1) How do overall frequency distributions of burn-severity classes compare between first and second fires? (2) In a given location, how does burn severity of the second fire relate to that of the first? (3) Do interactions between successive fires vary by forest zone or the interval between fires? (4) What factors increase the probability of burning twice as stand-replacing fire? Within the study area, 138,061 ha burned twice between 1984 and 2010. Overall, frequency distributions of burn severity classes (low, moderate, high; quantified using relativized remote sensing indices) were similar between the first and second fires; however burn severity was 5-13% lower in second fires on average. Negative interactions between fires were most pronounced in lower-elevation forests and woodlands, when fire intervals were <10 yr, and when burn severity was low in the first fire. When the first fire burned as high severity and fire intervals exceeded 10-12 yr, burn-severity interactions switched from negative to positive, with high-severity fire begetting subsequent high-severity fire. Locations most likely to experience successive stand-replacing fires were high-elevation forests, which are adapted to high-severity fire, and areas conducive to abundant post-fire tree regeneration. Broadly similar severities among short-interval "re-burns" and other wildfires indicate that positive severity feedbacks, an oft-posited agent of ecosystem decline or state shift, are not an inevitable outcome of re-burning. Nonetheless, context-dependent shifts in both the magnitude and direction of wildfire interactions (associated with forest zone, initial burn-severity, and disturbance interval) illustrate complexities in disturbance interactions and can inform management and predictions of future system dynamics. © 2016 by the Ecological Society of America.

Total N exports from once vs. repeatedly burnt Pine plantations

NASA Astrophysics Data System (ADS)

Gonzalez Pelayo, Oscar; Hosseini, Mohammadreza; Varandas, Daniela; Machado, Ana Isabel; Prats Alegre, Sergio; Coelho, Celeste O. A.; Geissen, Violette; Ritsema, Coen; Keizer, Jan Jacob

2014-05-01

Post-fire nutrient losses in Mediterranean forested areas have been suggested as a key driver for ecosystem degradation. The role of fire recurrence in soil nutrient depletion, however, has been poorly studied. The EU-funded CASCADE project addresses this research gap in the study case in Portugal, having as overarching aim to assess if repeated wildfires lead to land degradation in Maritime Pine stands through a gradual process or, instead, through tipping-points in plant-water-soil relationships. Following a large wildfire in September 2012 affecting more than 3000 ha in the municipality of Viseu (central Portugal), total N losses are being monitored in three zones: 4x burnt since 1975; 1x burnt since 197, i.e. in 2012); unburnt since 1975. Within each zone, three replicate slopes were selected with similar slope angles and expositions and, at each slope, three pairs of erosion plots of approximately 0.25 m2 were installed on the lower, middle and lower slope section. Additionally, a catchment outlet within the 4x burned zones was equipped with a gauging station for automatic recording of water level sensor and tubidity and for collecting stream flow samples using an automatic sampler. Preliminary results from the first 6 months after the 2012-wildfire suggested that total N losses were, on average, twice as high at the 4x times burned slopes than at the 1x burned slopes. Nonetheless, temporal patterns in average losses during these initial six months were similar for the two zones. By contrast, the results obtained during the subsequent spring and summer seasons suggested that average total N losses from the 1x burned slopes closely approximated those from the 4x burned slopes. At the unburned slopes, total N losses were very small and limited to few rainfall events. Interestingly, at the catchment outlet the total N values were 66% higher compared to the 4x times burned microplots, highlighting the importance of up-scaling effects in terms of nutrient losses. Preliminary results on total N losses during the first post-fire year showed that nutrient depletion can be triggered by increasing the fire regime. The up-scaling effect suggested an increase in nutrient exportations from micro-plot to catchment scale. These results are being further investigated to establish the relationships between soil fertility losses and fire recurrence.

Wildfire effects on vadose zone hydrology in forested boreal peatland microforms

NASA Astrophysics Data System (ADS)

Thompson, Dan K.; Waddington, James M.

2013-04-01

SummaryPeatland vulnerability to wildfire disturbance has been shown to vary as a function of hummock and hollow microforms and vadose zone hydrology, with low-lying hollow microforms most susceptible to deep combustion of peat. To better understand how this microform induced pattern of burning alters vadose water storage, pore-water pressure, and water table relationships, we examined a paired burned and unburned peatland in the boreal plain region of north central Alberta. Water table response to rain events increased significantly after wildfire, resulting in a more variable unsaturated zone thickness that was more responsive to smaller rain events. Water storage losses in the vadose zone occurred primarily at depths greater than 15 cm. Large peat surface water loss occurred in hummock microforms in the early spring due to the presence of unsaturated frozen peat at depth, likely a result of a vapour gradient from the unfrozen peat into the frozen peat underneath. During this period, the loss of water storage in the vadose zone satisfied up to 25% of daily evaporative demand, compared to only 3-5% during ice-free periods. A similar but less severe drying was observed late in summer, with burned hummocks the most vulnerable with high pore-water pressures. The enhanced surface drying observed is a precursor to high pore-water pressure conditions that inhibit Sphagnum regeneration. Our observations point to a paradox where the hummocks, being most resistant to combustion, are themselves most prone to high pore-water pressures following wildfire. The harsher hummock environment may contribute to the observed delay in post-fire Sphagnum regeneration in hummocks compared to hollows.

Reassessment of the use of fire as a management tool in deciduous forests of eastern North America.

PubMed

Matlack, Glenn R

2013-10-01

Prescribed burning is increasingly being used in the deciduous forests of eastern North America. Recent work suggests that historical fire frequency has been overestimated east of the prairie-woodland transition zone, and its introduction could potentially reduce forest herb and shrub diversity. Fire-history recreations derived from sedimentary charcoal, tree fire scars, and estimates of Native American burning suggest point-return times ranging from 5-10 years to centuries and millennia. Actual return times were probably longer because such records suffer from selective sampling, small sample sizes, and a probable publication bias toward frequent fire. Archeological evidence shows the environmental effect of fire could be severe in the immediate neighborhood of a Native American village. Population density appears to have been low through most of the Holocene, however, and villages were strongly clustered at a regional scale. Thus, it appears that the majority of forests of the eastern United States were little affected by burning before European settlement. Use of prescribed burning assumes that most forest species are tolerant of fire and that burning will have only a minimal effect on diversity. However, common adaptations such as serotiny, epicormic sprouting, resprouting from rhizomes, and smoke-cued germination are unknown across most of the deciduous region. Experimental studies of burning show vegetation responses similar to other forms of disturbance that remove stems and litter and do not necessarily imply adaptation to fire. The general lack of adaptation could potentially cause a reduction in diversity if burning were introduced. These observations suggest a need for a fine-grained examination of fire history with systematic sampling in which all subregions, landscape positions, and community types are represented. Responses to burning need to be examined in noncommercial and nonwoody species in rigorous manipulative experiments. Until such information is available, it seems prudent to limit the use of prescribed burning east of the prairie-woodland transition zone. © 2013 Society for Conservation Biology.

Improving the effectiveness of nighttime temporary traffic control warning devices, volume 1 : evaluation of lights on nighttime work zone channelization devices.

DOT National Transportation Integrated Search

2013-10-01

Currently, the Illinois Department of Transportation (IDOT) is one of the few state transportation agencies that : require warning lights on nighttime work zone channelization devices, such as drums and barricades. The intent : of the steady-burn, am...

40 CFR 52.1020 - Identification of plan.

Code of Federal Regulations, 2010 CFR

2010-07-01

... you wish to obtain materials from a docket in the EPA Headquarters Library, please call the Office of... 102 Open Burning 03/17/2005 02/21/2008, 73 FR 9459 Chapter 103 Fuel Burning Equipment Particular... Applicability. State of Maine MAPA 1 form for Chapter 102 Open Burning Regulation Maine 01/03/2003 02/21/2008...

40 CFR 52.1020 - Identification of plan.

Code of Federal Regulations, 2011 CFR

2011-07-01

... you wish to obtain materials from a docket in the EPA Headquarters Library, please call the Office of... 102 Open Burning 03/17/2005 02/21/2008, 73 FR 9459 Chapter 103 Fuel Burning Equipment Particular... Applicability. State of Maine MAPA 1 form for Chapter 102 Open Burning Regulation Maine 01/03/2003 02/21/2008...

Auxiliary reactor for a hydrocarbon reforming system

DOEpatents

Clawson, Lawrence G.; Dorson, Matthew H.; Mitchell, William L.; Nowicki, Brian J.; Bentley, Jeffrey M.; Davis, Robert; Rumsey, Jennifer W.

2006-01-17

An auxiliary reactor for use with a reformer reactor having at least one reaction zone, and including a burner for burning fuel and creating a heated auxiliary reactor gas stream, and heat exchanger for transferring heat from auxiliary reactor gas stream and heat transfer medium, preferably two-phase water, to reformer reaction zone. Auxiliary reactor may include first cylindrical wall defining a chamber for burning fuel and creating a heated auxiliary reactor gas stream, the chamber having an inlet end, an outlet end, a second cylindrical wall surrounding first wall and a second annular chamber there between. The reactor being configured so heated auxiliary reactor gas flows out the outlet end and into and through second annular chamber and conduit which is disposed in second annular chamber, the conduit adapted to carry heat transfer medium and being connectable to reformer reaction zone for additional heat exchange.

Mixing of Pure Air Jets with a Reacting Fuel-Rich Crossflow

NASA Technical Reports Server (NTRS)

Leong, M. Y.; Samuelsen, G. S.; Holdeman, J. D.

1997-01-01

Jets in a crossflow play an integral role in practical combustion systems such as can and annular gas turbine combustors in conventional systems, and the Rich-burn/Quick-mix/Lean-burn (RQL) combustor utilized in stationary applications and proposed for advanced subsonic and supersonic transports. The success of the RQL combustor rests with the performance of the quick-mixing section that bridges the rich and lean zones. The mixing of jet air with a rich crossflow to bring the reaction to completion in the lean zone must be performed rapidly and thoroughly in order to decrease the extent of near-stoichiometric fluid pocket formation. Fluid pockets at near-stoichiometric equivalence ratios are undesirable because the high temperatures attained accelerate pollutant formation kinetics associated with nitric oxide (NO). The present study develops a model experiment designed to reveal the processes that occur when jet air is introduced into hot effluent emanating from a fuel-rich reaction zone.

Pollution by Arsenic, Mercury and other Heavy Metals in Sunchulli mining district of Apolobamba (Bolivia)

NASA Astrophysics Data System (ADS)

Terán Mita, Tania; Faz Cano, Angel; Muñoz, Maria Angeles; Millán Gómez, Rocio; Chincheros Paniagua, Jaime

2010-05-01

In Bolivia, metal mining activities since historical times have been one of the most important sources of environmental pollution. This is the case of the National Area of Apolobamba Integrated Management (ANMIN of Apolobamba) in La Paz, Bolivia, where intense gold mining activities have been carried out from former times to the present, with very little gold extraction and very primitive mineral processing technology; in fact, mercury is still being used in the amalgam processes of the gold concentration, which is burned outdoors to recover the gold. Sunchullí is a representative mining district in ANMIN of Apolobamba where mining activity is mainly gold extraction and its water effluents go to the Amazonian basin; in this mining district the productivity of extracted mineral is very low but the processes can result in heavy-metal contamination of the air, water, soils and plants. Due to its high toxicity, the contamination by arsenic and mercury create the most critical environmental problems. In addition, some other heavy metals may also be present such as lead, copper, zinc and cadmium. These heavy metals could be incorporated in the trophic chain, through the flora and the fauna, in their bio-available and soluble forms. Inhabitants of this area consume foodcrops, fish from lakes and rivers and use the waters for the livestock, domestic use, and irrigation. The aim of this work was to evaluate the heavy metals pollution by gold mining activities in Sunchullí area. In Sunchullí two representative zones were distinguished and sampled. Zone near the mining operation site was considered as affected by mineral extraction processes, while far away zones represented the non affected ones by the mining operation. In each zone, 3 plots were established; in each plot, 3 soil sampling points were selected in a random manner and analysed separately. In each sampling point, two samples were taken, one at the surface, from 0-5 cm depth (topsoil), and the other between 5 and 15 cm (subsurface). In addition, surface soils from mercury burn areas were also taken. Arsenic, mercury, lead, copper, zinc and cadmium total, DTPA and water extractable metals were determined. In both zones, the results show that mining activities do not increase heavy metals levels except for arsenic (17.20 - 69.25 mg/kg) that presents high concentrations surpassing the Belgium reference levels (19.00 mg/kg), in some cases stands out the high mercury values in the affected zone (2.07 mg/kg, 1.18 mg/kg, 1.93 mg/kg). The most polluted soils are mercury burn areas with high levels of mercury (4.21 - 21.79 mg/kg) surpassing levels according to the Holland regulation (0.3 mg/kg). Workers and population are in close contact with these soils without any type of protection.

Area burned in alpine treeline ecotones reflects region-wide trends

Treesearch

C. Alina Cansler; Donald McKenzie; Charles B. Halpern

2016-01-01

The direct effects of climate change on alpine treeline ecotones – the transition zones between subalpine forest and non-forested alpine vegetation – have been studied extensively, but climate-induced changes in disturbance regimes have received less attention. To determine if recent increases in area burned extend to these higher-elevation landscapes, we analysed...

Traveling-Wave Thermoacoustic Engines With Internal Combustion

DOEpatents

Weiland, Nathan Thomas; Zinn, Ben T.; Swift, Gregory William

2004-05-11

Thermoacoustic devices are disclosed wherein, for some embodiments, a combustion zone provides heat to a regenerator using a mean flow of compressible fluid. In other embodiments, burning of a combustible mixture within the combustion zone is pulsed in phase with the acoustic pressure oscillations to increase acoustic power output. In an example embodiment, the combustion zone and the regenerator are thermally insulated from other components within the thermoacoustic device.

On issue of increasing profitability of automated energy technology complexes for preparation and combustion of water-coal suspensions

NASA Astrophysics Data System (ADS)

Brylina, O. G.; Osintsev, K. V.; Prikhodko, YU S.; Savosteenko, N. V.

2018-03-01

The article considers the issues of energy technological complexes economy increase on the existing techniques of water-coal suspensions preparation and burning basis due to application of highly effective control systems of electric drives and neurocontrol. The automated control system structure for the main boiler components is given. The electric drive structure is disclosed by the example of pumps (for transfer of coal-water mash and / or suspension). A system for controlling and diagnosing a heat and power complex based on a multi-zone regulator is proposed. The possibility of using neural networks for implementing the control algorithms outlined in the article is considered.

The First 3D Simulations of Carbon Burning in a Massive Star

NASA Astrophysics Data System (ADS)

Cristini, A.; Meakin, C.; Hirschi, R.; Arnett, D.; Georgy, C.; Viallet, M.

2017-11-01

We present the first detailed three-dimensional hydrodynamic implicit large eddy simulations of turbulent convection for carbon burning. The simulations start with an initial radial profile mapped from a carbon burning shell within a 15 M⊙ stellar evolution model. We considered 4 resolutions from 1283 to 10243 zones. These simulations confirm that convective boundary mixing (CBM) occurs via turbulent entrainment as in the case of oxygen burning. The expansion of the boundary into the surrounding stable region and the entrainment rate are smaller at the bottom boundary because it is stiffer than the upper boundary. The results of this and similar studies call for improved CBM prescriptions in 1D stellar evolution models.

Numerical and experimental investigation of the effect of geometry on combustion characteristics of solid-fuel ramjet

NASA Astrophysics Data System (ADS)

Gong, Lunkun; Chen, Xiong; Musa, Omer; Yang, Haitao; Zhou, Changsheng

2017-12-01

Numerical and experimental investigation on the solid-fuel ramjet was carried out to study the effect of geometry on combustion characteristics. The two-dimensional axisymmetric program developed in the present study adopted finite rate chemistry and second-order moment turbulence-chemistry models, together with k-ω shear stress transport (SST) turbulence model. Experimental data were obtained by burning cylindrical polyethylene using a connected pipe facility. The simulation results show that a fuel-rich zone near the solid fuel surface and an air-rich zone in the core exist in the chamber, and the chemical reactions occur mainly in the interface of this two regions; The physical reasons for the effect of geometry on regression rate is the variation of turbulent viscosity due to the geometry change. Port-to-inlet diameter ratio is the main parameter influencing the turbulent viscosity, and a linear relationship between port-to-inlet diameter and regression rate were obtained. The air mass flow rate and air-fuel ratio are the main influencing factors on ramjet performances. Based on the simulation results, the correlations between geometry and air-fuel ratio were obtained, and the effect of geometry on ramjet performances was analyzed according to the correlation. Three-dimensional regression rate contour obtained experimentally indicates that the regression rate which shows axisymmetric distribution due to the symmetry structure increases sharply, followed by slow decrease in axial direction. The radiation heat transfer in recirculation zone cannot be ignored. Compared with the experimental results, the deviations of calculated average regression rate and characteristic velocity are about 5%. Concerning the effect of geometry on air-fuel ratio, the deviations between experimental and theoretical results are less than 10%.

The progress of Chinese burn medicine from the Third Military Medical University-in memory of its pioneer, Professor Li Ao.

PubMed

Li, Haisheng; Zhou, Junyi; Peng, Yizhi; Zhang, Jiaping; Peng, Xi; Luo, Qizhi; Yuan, Zhiqiang; Yan, Hong; Peng, Daizhi; He, Weifeng; Wang, Fengjun; Liang, Guangping; Huang, Yuesheng; Wu, Jun; Luo, Gaoxing

2017-01-01

Professor Li Ao was one of the founders of Chinese burn medicine and one of the most renowned doctors and researchers of burns in China. He established one of the Chinese earliest special departments for burns at Third Military Medical University (TMMU) in 1958. To memorialize Professor Li Ao on his 100th birthday in 2017 and introduce our extensive experience, it is our honor to briefly review the development and achievement of the Chinese burn medicine from TMMU. The epidemiology and outcomes of admitted burn patients since 1958 were reviewed. Furthermore, main achievements of basic and clinical research for the past roughly 60 years were presented. These achievements mainly included the Chinese Rule of Nine, fluid resuscitation protocol, experience in inhalation injury, wound treatment strategies, prevention and treatment of burn infections, nutrition therapy, organ support therapies, and rehabilitation. The progress shaped and enriched modern Chinese burn medicine and promoted the development of world burn medicine.

Particulate and trace gas emissions from large biomass fire in North America

Treesearch

Lawrence F. Radke; Dean A. Hegg; Peter V. Hobbs; J.David Nance; Jamie H. Lyons; Krista K. Laursen; Raymond E. Weiss; Phillip J. Riggan; Darold E. Ward

1991-01-01

In this chapter we describe the results of airborne studies of smokes from 17 biomass fuel fires, including 14 prescribed fires and 3 wildfires, burned primarily in the temperate zone of North America between 34° and 49°N latitude. The prescribed fires were in forested lands and logging debris and varied in areas burned from 10 to 700 hectares...

Cars Spectroscopy of Propellant Flames

DTIC Science & Technology

1983-11-01

applicability of CARS in studies of the combustion of propellants and other reactive systems. Broadband CARS spectra were obtained from both the reaction zone...ref 12). When ienited vith a flame, propellant burned in air with a luainous flame. A-e Ignittou with i hot wire resulted in flameless burning (fizz...ester). Current models of nitramine propellant combustion are essentially models of HMX (cyclotetranithylene tetranitramine) and RDX deflagration. The

Chapter 2 evolution of burn management in the u.s. Military: impact on nursing.

PubMed

Schmidt, Patricia; Mann-Salinas, Elizabeth A

2014-01-01

As the only burn center in the Department of Defense, the U.S. Army Institute of Surgical Research is the primary location for care of service members with burn injuries. The combat operations in Iraq and Afghanistan during the past decade have caused an increase in burn patients. As a result of this increased need, advancements in care were developed. The speed and precision of transporting patients from the battlefield to the burn center has improved over previous conflicts. Technological advancements to support treating complications of burn wound healing were leveraged and are now integrated into daily practice. Clinical decision support systems were developed and deployed at the burn center as well as to combat support hospitals in combat zones. Technology advancements in rehabilitation have allowed more service members to return to active duty or live productive civilian lives. All of these advancements were developed in a patient-centered, interdisciplinary environment where the nurses are integrated throughout the research process and clinical practice with the end goal of healing combat burns in mind.

Effects of normal acceleration on transient burning rate augmentation of an aluminized solid propellant

NASA Technical Reports Server (NTRS)

Northam, G. B.

1972-01-01

Instantaneous burning rate data for a polybutadiene acrylic acid propellant, containing 16 weight percent aluminum, were calculated from the pressure histories of a test motor with 96.77 sq cm of burning area and a 5.08-cm-thick propellant web. Additional acceleration tests were conducted with reduced propellant web thicknesses of 3.81, 2.54, and 1.27 cm. The metallic residue collected from the various web thickness tests was characterized by weight and shape and correlated with the instantaneous burning rate measurements. Rapid depressurization extinction tests were conducted in order that surface pitting characteristics due to localized increased burning rate could be correlated with the residue analysis and the instantaneous burning rate data. The acceleration-induced burning rate augmentation was strongly dependent on propellant distance burned, or burning time, and thus was transient in nature. The results from the extinction tests and the residue analyses indicate that the transient rate augmentation was highly dependent on local enhancement of the combustion zone heat feedback to the surface by the growth of molten residue particles on or just above the burning surface. The size, shape, and number density of molten residue particles, rather than the total residue weight, determined the acceleration-induced burning rate augmentation.

Addition agents effects on hydrocarbon fuels burning

NASA Astrophysics Data System (ADS)

Larionov, V. M.; Mitrofanov, G. A.; Sakhovskii, A. V.

2016-01-01

Literature review on addition agents effects on hydrocarbon fuels burning has been conducted. The impact results in flame pattern and burning velocity change, energy efficiency increase, environmentally harmful NOx and CO emission reduction and damping of self-oscillations in flow. An assumption about water molecules dissociation phenomenon existing in a number of practical applications and being neglected in most explanations for physical- chemical processes taking place in case of injection of water/steam into combustion zone has been noted. The hypothesis about necessity of water dissociation account has been proposed. It can be useful for low temperature combustion process control and NOx emission reduction.

The Detection of Burn-Through Weld Defects Using Noncontact Ultrasonics

PubMed Central

Abbasi, Zeynab; Yuhas, Donald; Zhang, Lu; Basantes, Alexandra-Del-Carmen; Tehrani, Niloofar Nabili; Ozevin, Didem; Indacochea, Ernesto

2018-01-01

Nearly all manufactured products in the metal industry involve welding. The detection and correction of defects during welding improve the product reliability and quality, and prevent unexpected failures. Nonintrusive process control is critical for avoiding these defects. This paper investigates the detection of burn-through damage using noncontact, air-coupled ultrasonics, which can be adapted to the immediate and in-situ inspection of welded samples. The burn-through leads to a larger volume of degraded weld zone, providing a resistance path for the wave to travel which results in lower velocity, energy ratio, and amplitude. Wave energy dispersion occurs due to the increase of weld burn-through resulting in higher wave attenuation. Weld sample micrographs are used to validate the ultrasonic results. PMID:29342875

Droplet burning at zero G

NASA Technical Reports Server (NTRS)

Williams, F. A.

1978-01-01

Questions of the importance and feasibility of performing experiments on droplet burning at zero gravity in Spacelab were studied. Information on the physics and chemistry of droplet combustion, with attention directed specifically to the chemical kinetics, heat and mass transfer, and fluid mechanics of the phenomena involved, are presented. The work was divided into three phases, the justification, the feasibility, and the conceptual development of a preliminary design. Results from the experiments performed revealed a few new facts concerning droplet burning, notably burning rates in excess of theoretical prediction and a phenomenon of flash extinction, both likely traceable to accumulation of carbon produced by gas-phase pyrolysis in the fuel-rich zone enclosed by the reaction surface. These experiments also showed that they were primarily due to timing difficulties.

Recovery of the Chaparral Riparian Zone After Wildfire

Treesearch

Frank W. Davis; Edward A. Keller; Anuja Parikh; Joan Florsheim

1989-01-01

After the Wheeler Fire in southern California in July 1985, we monitored sediment deposition and vegetation recovery in a section of the severely burned chaparral riparian zone of the North Fork of Matilija Creek, near Ojai, California. Increased runoff was accompanied by low magnitude debris flows and fluvial transport of gravel, most of which was added to the channel...

Stellar evolution with turbulent diffusion. I. A new formalism of mixing.

NASA Astrophysics Data System (ADS)

Deng, L.; Bressan, A.; Chiosi, C.

1996-09-01

In this paper we present a new formulation of diffusive mixing in stellar interiors aimed at casting light on the kind of mixing that should take place in the so-called overshoot regions surrounding fully convective zones. Key points of the analysis are the inclusion the concept of scale length most effective for mixing, by means of which the diffusion coefficient is formulated, and the inclusion of intermittence and stirring, two properties of turbulence known from laboratory fluid dynamics. The formalism is applied to follow the evolution of a 20Msun_ star with composition Z=0.008 and Y=0.25. Depending on the value of the diffusion coefficient holding in the overshoot region, the evolutionary behaviour of the test stars goes from the case of virtually no mixing (semiconvective like structures) to that of full mixing over there (standard overshoot models). Indeed, the efficiency of mixing in this region drives the extension of the intermediate fully convective shell developing at the onset of the the shell H-burning, and in turn the path in the HR Diagram (HRD). Models with low efficiency of mixing burn helium in the core at high effective temperatures, models with intermediate efficiency perform extended loops in the HRD, finally models with high efficiency spend the whole core He-burning phase at low effective temperatures. In order to cast light on this important point of stellar structure, we test whether or not in the regions of the H-burning shell a convective layer can develop. More precisely, we examine whether the Schwarzschild or the Ledoux criterion ought to be adopted in this region. Furthermore, we test the response of stellar models to the kind of mixing supposed to occur in the H-burning shell regions. Finally, comparing the time scale of thermal dissipation to the evolutionary time scale, we get the conclusion that no mixing in this region should occur. The models with intermediate efficiency of mixing and no mixing at all in the shell H-burning regions are of particular interest as they possess at the same time evolutionary characteristics that are separately typical of models calculated with different schemes of mixing. In other words, the new models share the same properties of models with standard overshoot, namely a wider main sequence band, higher luminosity, and longer lifetimes than classical models, but they also possess extended loops that are the main signature of the classical (semiconvective) description of convection at the border of the core.

Influence of water mist on propagation and suppression of laminar premixed flame

NASA Astrophysics Data System (ADS)

Belyakov, Nikolay S.; Babushok, Valeri I.; Minaev, Sergei S.

2018-03-01

The combustion of premixed gas mixtures containing micro droplets of water was studied using one-dimensional approximation. The dependencies of the burning velocity and flammability limits on the initial conditions and on the properties of liquid droplets were analyzed. Effects of droplet size and concentration of added liquid were studied. It was demonstrated that the droplets with smaller diameters are more effective in reducing the flame velocity. For droplets vaporizing in the reaction zone, the burning velocity is independent of droplet size, and it depends only on the concentration of added liquid. With further increase of the droplet diameter the droplets are passing through the reaction zone with completion of vaporization in the combustion products. It was demonstrated that for droplets above a certain size there are two stable stationary modes of flame propagation with transition of hysteresis type. The critical conditions of the transition are due to the appearance of the temperature maximum at the flame front and the temperature gradient with heat losses from the reaction zone to the products, as a result of droplet vaporization passing through the reaction zone. The critical conditions are similar to the critical conditions of the classical flammability limits of flame with the thermal mechanism of flame propagation. The maximum decrease in the burning velocity and decrease in the combustion temperature at the critical turning point corresponds to predictions of the classical theories of flammability limits of Zel'dovich and Spalding. The stability analysis of stationary modes of flame propagation in the presence of water mist showed the lack of oscillatory processes in the frames of the assumed model.

Early Reconstruction of Distal Leg and Foot in Acute High-Voltage Electrical Burn: Does Location of Pedicle in the Zone of Injury Affect the Outcome of Distally Based Sural Flap?

PubMed

Asʼadi, Kamran; Salehi, Seyed Hamid; Shoar, Saeed

2017-01-01

Distally based fasciocutaneous sural flap is popular in the reconstruction of distal leg and foot burns. However, utilization of this technique in high-voltage electrical injury has been challenging. The present study aimed to compare the outcome of early aggressive debridement and coverage of contact point of acute high-voltage electrical injury using distally based fasciocutaneous sural flap between high-risk and low-risk patients defined by the anatomic proximity of the flap pedicle to the zone of injury. A total of 51 patients with contact point of high-voltage electrical burn (HVEB) in distal leg and foot undergoing distally based fasciocutaneous sural flap were included in this prospective clinical study. In 28 patients, the flap pedicle was not involved in the contact point of high-voltage electrical injury (low risk/control group), whereas in 21 patients, it was located inside the zone of injury (high-risk/case group). Patients were followed up for a median of 21 months (range, 12-44 months). Wound dimensions to be covered were relatively similar between the 2 groups. Complications of flap survival (primary outcome) and other minor early and late complications (secondary outcome) did not significantly differ between the 2 groups (P > 0.05). Provided that early and completed debridements of contact points of HVEB were achieved, distally based sural flap is feasible and there is reliable coverage in HVEB even in patients with flap pedicle located in vicinity of the zone of injury.

Using relative humidity to predict spotfire probability on prescribed burns

Treesearch

John R. Weir

2007-01-01

Spotfires have and always will be a problem that burn bosses and fire crews will have to contend with on prescribed burns. Weather factors (temperature, wind speed and relative humidity) are the main variables burn bosses can use to predict and monitor prescribed fire behavior. At the Oklahoma State University Research Range, prescribed burns are conducted during...

Initial Burn Pan (JMTF) Testing Results

DTIC Science & Technology

2016-03-01

of Testing and Materials (ASTM) standard for fire - resistant boom. It had not been used for over 15 years and was almost completely destroyed when...Environment Canada had produced operational guides, provided standards for fire - resistant booms and igniting techniques needed to perform offshore burns...are currently in the smoke zone; and the heat from the fire could be felt from that area. While no one was injured, some miscommunication at the

Apoptosis of hair follicle cells in the second-degree burn wound unders hypernatremic conditions.

PubMed

Harada, T; Izaki, S; Tsutsumi, H; Kobayashi, M; Kitamura, K

1998-08-01

Progressive burn wound necrosis is an important factor as a cause of delayed healing during clinical therapy of burns. Among the causes of progressive necrosis have been attributed an insufficient blood supply or a dehydration at the zone of stasis just beneath the zone of coagulation. In a previous study evidence was presented that hypernatremia, an osmotic injury, may act to promote progressive tissue or cell death of the superficial dermal wound resulting from a heat injury. To test this hypothesis pathological features of cell death in the second-degree burn wound in the rat with hypernatremia were investigated and evidence for apoptosis in hair follicle cells was observed. Rats in the hypernatremic group were administered 10 ml of hypertonic sodium solution (850 meq 1(-1)) and the control rats were treated with 10 ml of hyponatremic solution (100 meq 1(-1)) to prevent hypernatremia. After 24 h postburn the average incidence of hair follicles (ratio to the normal skin) in the hypernatremic group was 30.1 +/-11.6 per cent and significantly lower when compared with the control group (87.6+/-6.0 per cent). The numbers of hair follicles were studied by haematoxylin and eosin stain, and the apoptotic process was investigated by an immunochemical assay and electron microscopy.

Historical record of black carbon in urban soils and its environmental implications.

PubMed

He, Yue; Zhang, Gan-Lin

2009-10-01

Energy use in urbanization has fundamentally changed the pattern and fluxes of carbon cycling, which has global and local environmental impacts. Here we have investigated organic carbon (OC) and black carbon (BC) in six soil profiles from two contrast zones in an ancient city (Nanjing) in China. BC in soils was widely variable, from 0.22 to 32.19 g kg(-1). Its average concentration in an ancient residential area (Zone 1) was, 0.91 g kg(-1), whereas in Zone 2, an industrial and commercial area, the figure was 8.62 g kg(-1). The ratio of BC/OC ranged from 0.06 to 1.29 in soil profiles, with an average of 0.29. The vertical distribution of BC in soil is suggested to reflect the history of BC formation from burning of biomass and/or fossil fuel. BC in the surface layer of soils was mainly from traffic emission (especially from diesel vehicles). In contrast, in cultural layers BC was formed from historical coal use. The contents of BC and the ratio of BC/OC may reflect different human activities and pollution sources in the contrasting urban zones. In addition, the significant correlation of heavy metals (Cu, Pb, and Zn) with BC contents in some culture layers suggests the sorption of the metals by BC or their coexistence resulted from the coal-involved smelting.

Predictive Factors of Mortality in Burn Patients

PubMed Central

Fazeli, Shahram; Karami-Matin, Reza; Kakaei, Neda; Pourghorban, Samira; Safari-Faramani, Roya; Safari-Faramani, Bahare

2014-01-01

Background: Burn injuries impose a considerable burden on healthcare systems in Iran. It is among the top ten causes of mortality and a main cause of disability. Objectives: This study aimed to examine factors influencing mortality in burn patients admitted to the main educational tertiary referral hospital in Kermanshah. Patients and Methods: All patients admitted to the Imam Khomeini Hospital (from March 2011 to March 2012), due to thermal burn injuries were included in the study. We applied multiple logistic regressions to identify risk and protective factors of mortality. Also we calculated lethal area fifty percent (LA50), as an aggregate index for hospital quality. Results: During the study period, 540 burn patients were admitted. Male to female ratio was 1.12:1. Twenty three percent of the patients were less than 15 years-old. Median of age was 25 years (Inter Quartile Range, 16 - 37). Overall, probability of death was 25.8%. Lethal area fifty percent (LA50) was 50.82 (CI 95%: 47.76 - 54.48). In the final model, after adjustment of sex, age, total body surface area (TBSA), cause of burn and it’s severity, female gender (P < 0.05), age ≥ 60 years (in comparison with age less than 15 years, P < 0.05) and larger burn size (P < 0.0001) were identified as the main risk factors of death in these patients. Conclusions: Findings showed that the main risk factors of death were female gender, burn size and old age. Directing more attention to these vulnerable patients is required to reduce mortality and improve patient survival. PMID:24719826

Combustion of Methane Hydrate

NASA Astrophysics Data System (ADS)

Roshandell, Melika

A significant methane storehouse is in the form of methane hydrates on the sea floor and in the arctic permafrost. Methane hydrates are ice-like structures composed of water cages housing a guest methane molecule. This caged methane represents a resource of energy and a potential source of strong greenhouse gas. Most research related to methane hydrates has been focused on their formation and dissociation because they can form solid plugs that complicate transport of oil and gas in pipelines. This dissertation explores the direct burning of these methane hydrates where heat from the combustion process dissociates the hydrate into water and methane, and the released methane fuels the methane/air diffusion flame heat source. In contrast to the pipeline applications, very little research has been done on the combustion and burning characteristics of methane hydrates. This is the first dissertation on this subject. In this study, energy release and combustion characteristics of methane hydrates were investigated both theoretically and experimentally. The experimental study involved collaboration with another research group, particularly in the creation of methane hydrate samples. The experiments were difficult because hydrates form at high pressure within a narrow temperature range. The process can be slow and the resulting hydrate can have somewhat variable properties (e.g., extent of clathration, shape, compactness). The experimental study examined broad characteristics of hydrate combustion, including flame appearance, burning time, conditions leading to flame extinguishment, the amount of hydrate water melted versus evaporated, and flame temperature. These properties were observed for samples of different physical size. Hydrate formation is a very slow process with pure water and methane. The addition of small amounts of surfactant increased substantially the hydrate formation rate. The effects of surfactant on burning characteristics were also studied. One finding from the experimental component of the research was that hydrates can burn completely, and that they burn most rapidly just after ignition and then burn steadily when some of the water in the dissociated zone is allowed to drain away. Excessive surfactant in the water creates a foam layer around the hydrate that acts as an insulator. The layer prevents sufficient heat flux from reaching the hydrate surface below the foam to release additional methane and the hydrate flame extinguishes. No self-healing or ice-freezing processes were observed in any of the combustion experiments. There is some variability, but a typical hydrate flame is receiving between one and two moles of water vapor from the liquid dissociated zone of the hydrate for each mole of methane it receives from the dissociating solid region. This limits the flame temperature to approximately 1800 K. In the theoretical portion of the study, a physical model using an energy balance from methane combustion was developed to understand the energy transfer between the three phases of gas, liquid and solid during the hydrate burn. Also this study provides an understanding of the different factors impacting the hydrate's continuous burn, such as the amount of water vapor in the flame. The theoretical study revealed how the water layer thickness on the hydrate surface, and its effect on the temperature gradient through the dissociated zone, plays a significant role in the hydrate dissociation rate and methane release rate. Motivated by the above mentioned observation from the theoretical analysis, a 1-D two-phase numerical simulation based on a moving front model for hydrate dissociation from a thermal source was developed. This model was focused on the dynamic growth of the dissociated zone and its effect on the dissociation rate. The model indicated that the rate of hydrate dissociation with a thermal source is a function of the dissociated zone thickness. It shows that in order for a continuous dissociation and methane release, some of the water from the dissociated zone needs to be drained. The results are consistent with the experimental observations. The understanding derived from the experiments and the numerical model permitted a brief exploration into the potential effects of pressure on the combustion of methane hydrates. The prediction is that combustion should improve under high pressure conditions because the evaporation of water is suppressed allowing more energy into the dissociation. Future experiments are needed to validate these initial findings.

Coal combustion system

DOEpatents

Wilkes, Colin; Mongia, Hukam C.; Tramm, Peter C.

1988-01-01

In a coal combustion system suitable for a gas turbine engine, pulverized coal is transported to a rich zone combustor and burned at an equivalence ratio exceeding 1 at a temperature above the slagging temperature of the coal so that combustible hot gas and molten slag issue from the rich zone combustor. A coolant screen of water stretches across a throat of a quench stage and cools the combustible gas and molten slag to below the slagging temperature of the coal so that the slag freezes and shatters into small pellets. The pelletized slag is separated from the combustible gas in a first inertia separator. Residual ash is separated from the combustible gas in a second inertia separator. The combustible gas is mixed with secondary air in a lean zone combustor and burned at an equivalence ratio of less than 1 to produce hot gas motive at temperature above the coal slagging temperature. The motive fluid is cooled in a dilution stage to an acceptable turbine inlet temperature before being transported to the turbine.

Mechanism of influence water vapor on combustion characteristics of propane-air mixture

NASA Astrophysics Data System (ADS)

Larionov, V. M.; Mitrofanov, G. A.; Sachovskii, A. V.; Kozar, N. K.

2016-01-01

The article discusses the results of an experimental study of the effect of water vapor at the flame temperature. Propane-butane mixture with air is burning on a modified Bunsen burner. Steam temperature was varied from 180 to 260 degrees. Combustion parameters changed by steam temperature and its proportion in the mixture with the fuel. The fuel-air mixture is burned in the excess air ratio of 0.1. It has been established that the injection of steam changes the characteristics of combustion fuel-air mixture and increase the combustion temperature. The concentration of CO in the combustion products is substantially reduced. Raising the temperature in the combustion zone is associated with increased enthalpy of the fuel by the added steam enthalpy. Reducing the concentration of CO is caused by decrease in the average temperature in the combustion zone by applying steam. Concentration of active hydrogen radicals and oxygen increases in the combustion zone. That has a positive effect on the process of combustion.

The Impact of Fire on Active Layer Thicknes

NASA Astrophysics Data System (ADS)

Schaefer, K. M.; Parsekian, A.; Natali, S.; Ludwig, S.; Michaelides, R. J.; Zebker, H. A.; Chen, J.

2016-12-01

Fire influences permafrost thermodynamics by darkening the surface to increase solar absorption and removing insulating moss and organic soil, resulting in an increase in Active Layer Thickness (ALT). The summer of 2015 was one of the worst fire years on record in Alaska with multiple fires in the Yukon-Kuskokwim (YK) Delta. To understand the impacts of fire on permafrost, we need large-scale, extensive measurements of ALT both within and outside the fire zones. In August 2016, we surveyed ALT across multiple fire zones in the YK Delta using Ground Penetrating Radar (GPR) and mechanical probing. GPR uses pulsed, radio-frequency electromagnetic waves to noninvasively image the subsurface and is an effective tool to quickly map ALT over large areas. We supplemented this ALT data with measurements of Volumetric Water Content (VWC), Organic Layer Thickness (OLT), and burn severity. We quantified the impacts of fire by statistically comparing the measurements inside and outside the fire zones and statistically regressing ALT against VWC, change in OLT, and burn severity.

Post-wildfire effects on carbon and water vapour dynamics in a Spanish black pine forest.

PubMed

Dadi, T; Rubio, E; Martínez-García, E; López-Serrano, F R; Andrés-Abellán, M; García-Morote, F A; De las Heras, J

2015-04-01

Two eddy covariance systems were installed in a high-severity burned zone (BZ) and an adjacent unburned (UNB) zone to monitor water vapour and carbon dioxide fluxes for 21 months (from June 2011 to February 2013) at a Spanish black pine forest affected by a stand-replacing wildfire and located in a mountainous area of central-eastern Spain. The differences between both sites were significant especially during the growing season, affecting gross primary productivity (GPP) more than ecosystem respiration (Reco). Net ecosystem exchange (NEE) for 2012 was -3.97 and 1.80 t C ha(-1) year(-1) for the unburned and burned sites, respectively, the GPP being 64% lower for the BZ than the UNB zone. Evapotranspiration (ET) at the UNB was 18% greater than at the BZ. Difference between sites was 160 mm during the whole studied period. This study reflects the effect of one of the major disturbances that can affect Mediterranean ecosystems, showing that carbon fluxes are more dramatically concerned than water vapour fluxes.

Heat Effects of Promoters and Determination of Burn Criterion in Promoted Combustion Testing

NASA Technical Reports Server (NTRS)

Sparks, Kyle M.; Stoltzfus, Joel M.; Steinberg, Theodore A.; Lynn, David

2010-01-01

Promoted ignition testing (NASA Test 17) [1] is used to determine the relative flammability of metal rods in oxygen-enriched atmospheres. A promoter is used to ignite a metal sample rod, initiating sample burning. If a predetermined length of the sample burns, beyond the promoter, the material is considered flammable at the condition tested. Historically, this burn length has been somewhat arbitrary. Experiments were performed to better understand this test by obtaining insight into the effect a burning promoter has on the preheating of a test sample. Test samples of several metallic materials were prepared and coupled to fast-responding thermocouples along their length. Thermocouple measurements and test video were synchronized to determine temperature increase with respect to time and length along each test sample. A recommended flammability burn length, based on a sample preheat of 500 F, was determined based on the preheated zone measured from these tests. This length was determined to be 30 mm (1.18 in.). Validation of this length and its rationale are presented.

Pilot study of radiofrequency ablation therapy without surgical excision for T1 breast cancer: evaluation with MRI and vacuum-assisted core needle biopsy and safety management.

PubMed

Yamamoto, Naohito; Fujimoto, Hiroshi; Nakamura, Rikiya; Arai, Manabu; Yoshii, Atsushi; Kaji, Sachiko; Itami, Makiko

2011-01-01

There is increasing demand for minimally invasive treatments for small breast cancer mainly because of the desire for better cosmetic results. Although radiofrequency ablation (RFA) is an attractive approach as a local control method for small breast cancer, the problems of histological effectiveness and safety management remain. A total of 29 patients including one patient with bilateral breast cancer were enrolled in this study. The mean tumor size of 30 breasts was 12.8 mm (range 5-19 mm). Under general anesthesia, RFA was performed with a Cool-tip RF system (Valleylab, Boulder, CO, USA) after sentinel lymph node biopsy. Postoperative evaluation with magnetic resonance imaging (MRI) and vacuum-assisted core needle biopsy was done 3-4 weeks after RFA before radiotherapy. Ablated tumors were evaluated with hematoxylin-eosin (H&E) and nicotinamide adenine dinucleotide (NADH)-diaphorase staining. If needed, adjuvant chemo and/or endocrine therapy was performed. All patients except one completed one session of RFA. The mean temperature near the center of the tumors was 89.6°C (range 78-100°C). Postoperative MRI showed the ablated zone clearly in all patients. MRI revealed no hypervascularity of the tumors in the ablated zone. Evaluation with H&E staining of the tumors showed remarkable degenerative changes in only three patients. NADH-diaphorase staining showed no viable tumor tissue in 24 patients out of 26 examined. Three patients received small diameter grade 3 skin burns, two on the outside of the thigh from the grounding pad and one on the breast skin. One patient had a breast lesion like a chronic granulomatous mastitis resulting from overreaction of the ablated zone. RFA therapy appeared relevant and applicable for patients with small breast cancer. Because small skin burns were observed as adverse events, close attention should be paid in the course of the RFA procedure.

Ignition of an organic water-coal fuel droplet floating in a heated-air flow

NASA Astrophysics Data System (ADS)

Valiullin, T. R.; Strizhak, P. A.; Shevyrev, S. A.; Bogomolov, A. R.

2017-01-01

Ignition of an organic water-coal fuel (CWSP) droplet floating in a heated-air flow has been studied experimentally. Rank B2 brown-coal particles with a size of 100 μm, used crankcase Total oil, water, and a plasticizer were used as the main CWSP components. A dedicated quartz-glass chamber has been designed with inlet and outlet elements made as truncated cones connected via a cylindrical ring. The cones were used to shape an oxidizer flow with a temperature of 500-830 K and a flow velocity of 0.5-5.0 m/s. A technique that uses a coordinate-positioning gear, a nichrome thread, and a cutter element has been developed for discharging CWSP droplets into the working zone of the chamber. Droplets with an initial size of 0.4 to 2.0 mm were used. Conditions have been determined for a droplet to float in the oxidizer flow long enough for the sustainable droplet burning to be initiated. Typical stages and integral ignition characteristics have been established. The integral parameters (ignition-delay times) of the examined processes have been compared to the results of experiments with CWSP droplets suspended on the junction of a quick-response thermocouple. It has been shown that floating fuel droplets ignite much quicker than the ones that sit still on the thermocouple due to rotation of an CWSP droplet in the oxidizer flow, more uniform heating of the droplet, and lack of heat drainage towards the droplet center. High-speed video recording of the peculiarities of floatation of a burning fuel droplet makes it possible to complement the existing models of water-coal fuel burning. The results can be used for a more substantiated modeling of furnace CWSP burning with the ANSYS, Fluent, and Sigma-Flow software packages.

Reducing mode circulating fluid bed combustion

DOEpatents

Lin, Yung-Yi; Sadhukhan, Pasupati; Fraley, Lowell D.; Hsiao, Keh-Hsien

1986-01-01

A method for combustion of sulfur-containing fuel in a circulating fluid bed combustion system wherein the fuel is burned in a primary combustion zone under reducing conditions and sulfur captured as alkaline sulfide. The reducing gas formed is oxidized to combustion gas which is then separated from solids containing alkaline sulfide. The separated solids are then oxidized and recycled to the primary combustion zone.

Development of high-speed balancing technology

NASA Technical Reports Server (NTRS)

Demuth, R.; Zorzi, E.

1981-01-01

An investigation into laser material removal showed that laser burns act in a manner typical of mechanical stress raisers causing a reduction in fatigue strength; the fatigue strength is lowered relative to the smooth specimen fatigue strength. Laser-burn zones were studied for four materials: Alloy Steel 4340, Stainless Steel 17-4 PH, Inconel 718, and Aluminum Alloy 6061-T6. Calculations were made of stress concentration factors K, for laser-burn grooves of each material type. A comparison was then made to experimentally determine the fatigue strength reduction factor. These calculations and comparisons indicated that, except for the 17-4 PH material, good agreement (a ratio of close to 1.0) existed between Kt and Kf. The performance of the 17-4 PH material has been attributed to early crack initiation due to the lower fatigue resistance of the soft, unaged laser-affected zone. Also covered in this report is the development, implementation, and testing of an influence coefficient approach to balancing a long, slender shaft under applied-torque conditions. Excellent correlation existed between the analytically predicted results and those data obtained from testing.

Implementation of Smoothed Particle Hydrodynamics for Detonation of Explosive with Application to Rock Fragmentation

NASA Astrophysics Data System (ADS)

Pramanik, R.; Deb, D.

2015-07-01

The paper presents a methodology in the SPH framework to analyze physical phenomena those occur in detonation process of an explosive. It mainly investigates the dynamic failure mechanism in surrounding brittle rock media under blast-induced stress wave and expansion of high pressure product gases. A program burn model is implemented along with JWL equation of state to simulate the reaction zone in between unreacted explosive and product gas. Numerical examples of detonation of one- and two-dimensional explosive slab have been carried out to investigate the effect of reaction zone in detonation process and outward dispersion of gaseous product. The results are compared with those obtained from existing solutions. A procedure is also developed in SPH framework to apply continuity conditions between gas and rock interface boundaries. The modified Grady-Kipp damage model for the onset of tensile yielding and Drucker-Prager model for shear failure are implemented for elasto-plastic analysis of rock medium. The results show that high compressive stress causes high crack density in the vicinity of blast hole. The major principal stress (tensile) is responsible for forming radial cracks from the blast hole. Spalling zones are also developed due to stress waves reflected from the free surfaces.

Numerical simulations of microcrack-related damage and ignition behavior of mild-impacted polymer bonded explosives.

PubMed

Yang, Kun; Wu, Yanqing; Huang, Fenglei

2018-08-15

A physical model is developed to describe the viscoelastic-plastic deformation, cracking damage, and ignition behavior of polymer-bonded explosives (PBXs) under mild impact. This model improves on the viscoelastic-statistical crack mechanical model (Visco-SCRAM) in several respects. (i) The proposed model introduces rate-dependent plasticity into the framework which is more suitable for explosives with relatively high binder content. (ii) Damage evolution is calculated by the generalized Griffith instability criterion with the dominant (most unstable) crack size rather than the averaged crack size over all crack orientations. (iii) The fast burning of cracks following ignition and the effects of gaseous products on crack opening are considered. The predicted uniaxial and triaxial stress-strain responses of PBX9501 sample under dynamic compression loading are presented to illustrate the main features of the materials. For an uncovered cylindrical PBX charge impacted by a flat-nosed rod, the simulated results show that a triangular-shaped dead zone is formed beneath the front of the rod. The cracks in the dead zone are stable due to friction-locked stress state, whereas the cracks near the front edges of dead zone become unstable and turn into hotspots due to high-shear effects. Copyright © 2018 Elsevier B.V. All rights reserved.

Modelling fire frequency and area burned across phytoclimatic regions in Spain using reanalysis data and the Canadian Fire Weather Index System

NASA Astrophysics Data System (ADS)

Bedia, J.; Herrera, S.; Gutiérrez, J. M.

2013-09-01

We develop fire occurrence and burned area models in peninsular Spain, an area of high variability in climate and fuel types, for the period 1990-2008. We based the analysis on a phytoclimatic classification aiming to the stratification of the territory into homogeneous units in terms of climatic and fuel type characteristics, allowing to test model performance under different climatic and fuel conditions. We used generalized linear models (GLM) and multivariate adaptive regression splines (MARS) as modelling algorithms and temperature, relative humidity, precipitation and wind speed, taken from the ERA-Interim reanalysis, as well as the components of the Canadian Forest Fire Weather Index (FWI) System as predictors. We also computed the standardized precipitation-evapotranspiration index (SPEI) as an additional predictor for the models of burned area. We found two contrasting fire regimes in terms of area burned and number of fires: one characterized by a bimodal annual pattern, characterizing the Nemoral and Oro-boreal phytoclimatic types, and another one exhibiting an unimodal annual cycle, with the fire season concentrated in the summer months in the Mediterranean and Arid regions. The fire occurrence models attained good skill in most of the phytoclimatic zones considered, yielding in some zones notably high correlation coefficients between the observed and modelled inter-annual fire frequencies. Total area burned also exhibited a high dependence on the meteorological drivers, although their ability to reproduce the observed annual burned area time series was poor in most cases. We identified temperature and some FWI system components as the most important explanatory variables, and also SPEI in some of the burned area models, highlighting the adequacy of the FWI system for fire modelling applications and leaving the door opened to the development a more complex modelling framework based on these predictors. Furthermore, we demonstrate the potential usefulness of ERA-Interim reanalysis data for the reconstruction of historical fire-climate relationships at the scale of analysis. Fire frequency predictions may provide a preferable basis for past fire history reconstruction, long-term monitoring and the assessment of future climate impacts on fire regimes across regions, posing several advantages over burned area as response variable.

Aerosol Characteristics in the Northern Territory of Australia During the Dry Season With an Emphasis on Biomass Burning

DTIC Science & Technology

2005-08-01

properties and concentration of aerosol particles over the Amazon tropical forest during background and biomass burning ...characterize the seasonal variation (beginning to end) in the aerosol properties of the region. The main source of aerosol is biomass burning , and... Burning Emissions Part III: Intensive Optical Properties of Biomass Burning Particles , Atmos. Chem. Phys. Discuss., 4 5201-5260 45. see e. g.

Medical effects of volcanic eruptions

NASA Astrophysics Data System (ADS)

Baxter, Peter J.

1990-09-01

Excluding famine and tsunamis, most deaths in volcanic eruptions have been from pyroclastic flows and surges (nuées ardentes) and wet debris flows (lahars). Information on the causes of death and injury in eruptions is sparse but the available literature is summarised for the benefit of volcanologists and emergency planners. In nuées, thermal injury may be at least as important as asphyxia in causing immediate deaths. The high temperature of the gases and entrained particles readily causes severe burns to the skin and the air passages and the presence of both types of injury in an individual may combine to increase the delayed mortality risk from respiratory complications or from infection of burns. Trauma from missiles or body displacement is also common, but the role of asphyxiant or irritant gases, and steam, remains unclear. The ratio of dead: injured is much higher than in other natural disasters. At the periphery of a nuée being protected inside buildings which remain intact appears to greatly increase the chances of survival. In lahars, infected wounds and crush injury are the main delayed causes of death, and the scope for preventive measures, other than evacuation, is small. The evidence from Mount St. Helens, 1980, and other major eruptions indicates that, although mortality is high within the main zone of devastation and in the open, emergency planning should concentrate on the periphery of a nuée where preventive measures are feasible and could save many lives in densely populated areas.

Pre-main Sequence Evolution and the Hydrogen-Burning Minimum Mass

NASA Astrophysics Data System (ADS)

Nakano, Takenori

There is a lower limit to the mass of the main-sequence stars (the hydrogen-burning minimum mass) below which the stars cannot replenish the energy lost from their surfaces with the energy released by the hydrogen burning in their cores. This is caused by the electron degeneracy in the stars which suppresses the increase of the central temperature with contraction. To find out the lower limit we need the accurate knowledge of the pre-main sequence evolution of very low-mass stars in which the effect of electron degeneracy is important. We review how Hayashi and Nakano (1963) carried out the first determination of this limit.

A new metric for quantifying burn severity: The Relativized Burn Ratio

Treesearch

Sean A. Parks; Gregory K. Dillon; Carol Miller

2014-01-01

Satellite-inferred burn severity data have become increasingly popular over the last decade for management and research purposes. These data typically quantify spectral change between pre-and post-fire satellite images (usually Landsat). There is an active debate regarding which of the two main equations, the delta normalized burn ratio (dNBR) and its relativized form...

EOARC - Burns |

Science.gov Websites

Skip to Main Content Area Oregon State University USDA Agricultural Research Service | Donate | College of Agricultural Sciences EOARC - Burns banner image Resources Extn Agr Sci and NR Program Ag Agricultural Research Center! Front entrance located on Hwy 205 Front entrance located on Hwy 205 Main office

Chemical Burn-Induced Stromal Demarcation Line.

PubMed

Brosh, Koby; Rozenman, Yaacov

2016-02-01

A stromal demarcation line is a well-known sign after collagen cross-linking. It has been proposed that this line is the transition zone between cellular and acellular stroma, and thus it might reveal the depth of photochemical changes in the corneal stroma. We report 2 cases of a similar demarcation line after chemical alkali burns. To the best of our knowledge, this is the first report of a stromal demarcation line after a chemical burn. Two patients presented to the emergency department after an ocular alkali burn. At presentation, both had total corneal erosion, corneal edema, and limbal ischemia. After 12 to 15 days, a stromal line was apparent by both slit-lamp examination and anterior segment optical coherence tomography. The stromal demarcation lines disappeared approximately 3 months after the injury. A stromal demarcation line may appear not only after collagen cross-linking but also after a chemical burn. The line depth may be associated with the severity of the injury, and therefore, may have prognostic significance. Patients with chemical burns should be examined for evidence of a stromal line in the cornea.

Combustion characteristics and NO formation for biomass blends in a 35-ton-per-hour travelling grate utility boiler.

PubMed

Li, Zhengqi; Zhao, Wei; Li, Ruiyang; Wang, Zhenwang; Li, Yuan; Zhao, Guangbo

2009-04-01

Measurements were taken for a 35-ton-per-hour biomass-fired travelling grate boiler. Local mean concentrations of O(2), CO, SO(2) and NO gas species and gas temperatures were determined in the region above the grate. For a 28-ton-per-hour load, the mass ratios of biomass fly ash and boiler slag were 42% and 58%, the boiler efficiency was 81.56%, and the concentrations of NO(x) and SO(2) at 6% O(2) were 257 and 84 mg/m(3). For an 18-ton-per-hour load, the fuel burning zone was nearer to the inlet than it was for the 28-ton-per-hour load, and the contents of CO and NO in the fuel burning zone above the grate were lower.

Sector Tests of a Low-NO(sub x), Lean, Direct- Injection, Multipoint Integrated Module Combustor Concept Conducted

NASA Technical Reports Server (NTRS)

Tacina, Robert R.; Wey, Chang-Lie; Laing, Peter; Mansour, Adel

2002-01-01

The low-emissions combustor development described is directed toward advanced high pressure aircraft gas-turbine applications. The emphasis of this research is to reduce nitrogen oxides (NOx) at high-power conditions and to maintain carbon monoxide and unburned hydrocarbons at their current low levels at low power conditions. Low-NOx combustors can be classified into rich-burn and lean-burn concepts. Lean-burn combustors can be further classified into lean-premixed-prevaporized (LPP) and lean direct injection (LDI) concepts. In both concepts, all the combustor air, except for liner cooling flow, enters through the combustor dome so that the combustion occurs at the lowest possible flame temperature. The LPP concept has been shown to have the lowest NOx emissions, but for advanced high-pressure-ratio engines, the possibility of autoignition or flashback precludes its use. LDI differs from LPP in that the fuel is injected directly into the flame zone, and thus, it does not have the potential for autoignition or flashback and should have greater stability. However, since it is not premixed and prevaporized, good atomization is necessary and the fuel must be mixed quickly and uniformly so that flame temperatures are low and NOx formation levels are comparable to those of LPP. The LDI concept described is a multipoint fuel injection/multiburning zone concept. Each of the multiple fuel injectors has an air swirler associated with it to provide quick mixing and a small recirculation zone for burning. The multipoint fuel injection provides quick, uniform mixing and the small multiburning zones provide for reduced burning residence time, resulting in low NOx formation. An integrated-module approach was used for the construction where chemically etched laminates, diffusion bonded together, combine the fuel injectors, air swirlers, and fuel manifold into a single element. The multipoint concept combustor was demonstrated in a 15 sector test. The configuration tested had 36 fuel injectors and fuel-air mixers that replaced two fuel injectors in a conventional dual-annular combustor. During tests, inlet temperatures were up to 870 K and inlet pressures were up to 5400 kPa. A correlation was developed that related the NOx emissions with the inlet temperature, inlet pressure, fuel-air ratio, and pressure drop. At low-power conditions, fuel staging was used so that high combustion efficiency was obtained with only one-fourth of the fuel injectors flowing. The test facility had optical access, and visual images showed the flame to be very short, approximately 25 mm long.

Experiment for Regional Sources and Sinks of Oxidants (EXPRESSO): An overview

NASA Astrophysics Data System (ADS)

Delmas, R. A.; Druilhet, A.; Cros, B.; Durand, P.; Delon, C.; Lacaux, J. P.; Brustet, J. M.; SerçA, D.; Affre, C.; Guenther, A.; Greenberg, J.; Baugh, W.; Harley, P.; Klinger, L.; Ginoux, P.; Brasseur, G.; Zimmerman, P. R.; GréGoire, J. M.; Janodet, E.; Tournier, A.; Perros, P.; Marion, Th.; Gaudichet, A.; Cachier, H.; Ruellan, S.; Masclet, P.; Cautenet, S.; Poulet, D.; Biona, C. Bouka; Nganga, D.; Tathy, J. P.; Minga, A.; Loemba-Ndembi, J.; Ceccato, P.

1999-12-01

This paper presents an overview of the Experiment for Regional Sources and Sinks of Oxidents (EXPRESSO) including the objectives of the project, a detailed description of the characteristics of the experimental region and of field instrumentation deployed, and a summary of the main results of all components of the experiment. EXPRESSO is an international, multidisciplinary effort to quantify and better understand the processes controlling surface fluxes of photochemical precursors emitted by vegetation and biomass burning along a tropical forest to savanna gradient in central Africa. The experiment was conducted at the beginning of the dry season in November-December 1996. Three main research tools were deployed during this period: (1) the French research aircraft (Avion de Recherche Atmosphérique et de Télédétection, Fokker 27), instrumented for chemistry and flux measurements (CNRS- France), (2) two satellite receivers for in situ acquisition of National Oceanic and Atmospheric Administration-advanced very high resolution radiometer (NOAA-AVHRR) imagery for fire detection (EC-JRC, Ispra, Italy), and (3) a 65-m walkup tower installed at a tropical forest site in the Republic of Congo (National Center for Atmospheric Research, Boulder, Colorado). Average dynamic and turbulence characteristics over savanna and forest ecosystems were retrieved from aircraft measurements. They illustrate the complex atmospheric circulation occurring in this region in the vicinity of the Intertropical Convergence Zone. Satellite receivers were operated three times a day to produce maps of fire distribution. Statistics and mapping of burned surfaces from NOAA-AVHRR and ERS-Along Track Scanning Radiometer space systems have been developed. The influence of biogenic and biomass burning sources on the chemical composition of the lower atmosphere was studied through both aircraft and tower measurements. The EXPRESSO field campaign was followed by modeling efforts (regional and global scales) in which model components are evaluated using the experimental data.

Evaluation of infrastructure, equipment and training of 28 burn units/burn centers in Germany, Austria and Switzerland.

PubMed

Vogt, Peter M; Busche, Marc N

2011-03-01

Treatment of burn patients requires special training and skills, and an adequate infrastructure. In the United States, burn center referral criteria and requirements of burn centers are defined by the American Burn Association (ABA) in the Guidelines for the Operation of Burn Centers, and in Germany, by the German Society for Burn Treatment (DGV). The European Burn centers in Austria and the German-speaking part of Switzerland share the standards in the setting of the German-speaking Association for Burn Therapy (DAV) with some modifications. The aim of this study was to evaluate the current infrastructure of burn centers in the three German-speaking countries with respect to the existing guidelines. Therefore, guidelines for burn center referral criteria and burn center requirements were compared between the USA (ABA) and Germany (DGV). In addition, a questionnaire was sent to all burn centers in Germany, Austria and the German-speaking part of Switzerland, in order to collect current information regarding the architectural and medical infrastructure, available equipment and care-providing personnel. The comparison of guidelines for the USA and Germany revealed similar burn center referral criteria for both countries. With respect to burn center requirements, both the USA and Germany have similar requirements, albeit with different focus points. In Germany, the main focus lies on the infrastructural requirements for burn centers, while in the US, the main focus lies on the requirements for medical and nursing personnel. Critical review of the responses from the burn centers of German-speaking countries revealed that the biggest infrastructural differences among centers were observed in burn units providing pediatric care, as compared to adult burn centers. In summary, the DGV guidelines for German-speaking countries reflect an overall adoption of the ABA guidelines, and the burn centers included in this study met those requirements. As a result of the positive experience and effective treatment of burn patients in German-speaking countries, we recommend an adoption of the ABA guidelines to those countries and societies that are in need of appropriate standards of burn care. Copyright © 2010 Elsevier Ltd and ISBI. All rights reserved.

Spatial and temporal variations of soil moisture under Rosmarinus officinalis and Quercus coccifera in a burned soil

NASA Astrophysics Data System (ADS)

Gimeno-García, E.; Pascual-Aguilar, J. A.; Llovet, J.

2009-04-01

When studying surface runoff processes, measurement of the soil moisture content (SMC) at the surface could be used to identify sinks and sources areas of runoff. Surface soil moisture patterns variability have been studied in a burned Mediterranean semi-arid area. Since surface SMC and soil water repellency (SWR) are influenced by fire and vegetation (see previous abstract), and soil water dynamics and vegetation dynamics are functionally related, it could be expected to find some changes during the following months after fire when vegetation starts to recover. The identification of these changes is the main goal of this research. The study area is located at the municipality of Les Useres, 40 km from Castellón city (E Spain), where a wildfire occured in August 2007. We selected a burned SSE facing hillslope, located at 570 m a.s.l., with 12° slope angle, in which it was possible to identify the presence of two unique shrub species: Quercus coccifera L. and Rosmarinus officinalis L., which were distributed in a patchy mosaic. Twenty microsites with burned R. officinalis and eight microsites with burned Q. coccifera were selected in an area of 7 m wide by 14 m long. At the burned microsites, it was possible to distinguish three concentric zones (I, II and III) around the stumps showing differences on their soil surface appearance, which indicate a gradient of fire severity. Those differences were considered for field soil moisture measurements. Five measurements of SMC separated approximately 10 cm per zone at each microsite (n= 420) were carried out after different rainfall events. Volumetric soil moisture was measured by means of the moisture meter HH2 with ThetaProbe sensor type ML2x, 6 cm long. SMC was monitored on three occasions, always one day after the following rainfall events: (1) the first rainfall event after fire, when 11 mm were registered (Oct-07); (2) four months later than fire (Dec-07), after six consecutive raining days with a total rain volume of 172 mm; and (3) ten months after fire (Jun-08), when 50 mm were registered in the previous ten days. The spatial pattern of SMC was determined trough geostatistical analysis using GS+ software, calculating the semivariograms, to analyse the spatial correlation scale, interpolating data to estimate values of SMC at unsampled locations by means of kriging and finally, the results of kriging were displayed as different contour maps. Results showed that spatial pattern of SMC was highly variable, with important differences recorded within short distances. In fact, the range of spatial correlation (a0), which is the distance at that spatial correlation exists, varied between 0.5 to 1.4 m. A0 also varied according to the time from fire, with values of 0.5 m in the first rainfall after fire, 0.9 m four months later and 1.4 m ten months after fire occurs. This result suggests that the extent of the wettest areas increase as the vegetation recover. After the first rainfall, the SMC spatial pattern seems to be related to the soil microsite characteristics, mainly organic matter content, presence of hydrophobicity and soil clay content. Generally, the highest SMC (26-31%) appears at the burned bare soil areas. Four months later, as the same time as Q. coccifera resprouts, and in the R. officinalis microsites an important regrowth of Brachypodium resutum is observed, the spatial pattern of SMC changed according this plant cover distribution. This pattern is more clearly observed ten months after fire, when the highest SMC values were located at Q. coccifera and B. resutum areas (28-33%). At this time, no evidence of germination of R. officinalis (obligate seeder specie) was found. The lowest SMC (19-22%) appeared at the half lower part of the plot, where there was a central strip dominated by bare soil, with scarce presence of resprouter species. These results showed that at detailed working scale, the soil moisture pattern in this burned area was highly heterogeneous and the microsite characteristics (mainly soil properties and vegetation regrowth) seem to control the SMC spatial pattern. The interaction of soil-plant-water is more complex that the few environmental factors analysed here, and future research is needed to consider other site factors, such as microtopography, surface stoniness and outcrops, root density, between others. However, the obtained results reflect the capacity of vegetated patches to act as moisture holding areas ten months after fire occurs.

Microstructure of the combustion zone: Thin-binder AP-polymer sandwiches

NASA Technical Reports Server (NTRS)

Price, E. W.; Panyam, R. R.; Sigman, R. K.

1980-01-01

Experimental results are summarized for systematic quench-burning tests on ammonium perchlorate-HC binder sandwiches with binder thicknesses in the range 10 - 150 microns. Tests included three binders (polysulfide, polybutadiene-acrylonitrile, and hydroxy terminated polybutadiene), and pressures from 1.4 to 14 MPa. In addition, deflagration limits were determined in terms of binder thickness and pressure. Results are discussed in terms of a qualitative theory of sandwich burning consolidated from various sources. Some aspects of the observed results are explained only speculatively.

Correlating Meteorological, Satellite, and Ground Sampling Data to Determine Source of PM2.5 at Bagram Airfield (BAF), Afghanistan

DTIC Science & Technology

2015-07-08

Bethesda, MD 20814 D!SSERT A TION APPROVAL FOR THE MASTER IN SCIENCE IN PUBLIC HEAL TH DISSERTATION IN THE PREVENTIVE MEDICINE AND BIOMETRICS...such as asthma, bronchitis, cardiopulmonary disease, cancer , and premature death. One source of PM2.5 is open burning (i.e. burn pits), which is...combat zones encounter many different types of environmental hazards that are associated with adverse health outcomes (e.g. cancer and respiratory

Incidence and cost of non-fatal burns in Iran: a nationwide population-based study.

PubMed

Abouie, Abolfazl; Salamati, Payman; Hafezi-Nejad, Nima; Rahimi-Movaghar, Afarin; Saadat, Soheil; Amin-Esmaeili, Masoumeh; Sharifi, Vandad; Hajebi, Ahmad; Rahimi-Movaghar, Vafa

2018-03-01

To determine the incidence and cost of non-fatal burns in Iran; this cross-sectional household survey of a nationally representative sample of 15-64 years old was conducted. Through face-to-face interviews and telephone calls, the data on the demographics, history and cost of burns were collected. The annual incidence rate of burns was estimated 129.85 per 1000 population. Burns occurred higher in younger age, female gender and urban residency. The most common burn description was as follows: unpaid work (activity during burn), home (place of burn), heat and hot substances (mechanism of burn) and upper limb (site of burn). The average total cost of burn includes victims seeking medical care was US$124 per case. The main findings of this study suggest that burns are a major public health concern in Iran. To stop this important health issue, a national program for burn prevention and education must be developed.

Transfusion medicine in the Formosa Fun Coast water park explosion: The role of combined tissue and blood banking.

PubMed

Chang, Chih-Chun; Yeh, Chin-Chuan; Chu, Fang-Yeh

2016-10-01

The Formosa Fun Coast explosion, occurring in a recreational water park located in the Northern Taiwan on 27 June 2015, made 499 people burn-injured. For those who had severe burn trauma, surgical intervention and fluid resuscitation were necessary, and potential blood transfusion therapy could be initiated, especially during and after broad escharotomy. Here, we reviewed the literature regarding transfusion medicine and skin grafting as well as described the practicing experience of combined tissue and blood bank in the burn disaster in Taiwan. It was reported that patients who were severely burn-injured could receive multiple blood transfusions during hospitalization. Since the use of skin graft became a mainstay alternative for wound coverage after the early debridement of burn wounds at the beginning of the 20th century, the development of tissue banking program was initiated. In Taiwan, the tissue banking program was started in 2006. And the first combined tissue and blood bank was established in Far Eastern Memorial Hospital in 2010, equipped with the non-sterile, clean and sterile zones distinctly segregated with a unidirectional movement in the sterile area. The sterile zone was a class 10000 clean room equipped with high efficiency particulate air filter (HEPAF) and positive air pressure ventilation. The combined tissue and blood bank has been able to provide the assigned blood products and tissue graft timely and accurately, with the concepts of centralized management. In the future, the training of tissue and blood bank technicians would be continued and fortified, particularly on the regulation and quality control for further bio- and hemovigilance. Copyright © 2016 Elsevier Ltd. All rights reserved.

Towards a Better Understanding of Biomas Burning and Large Scale Climate Dynamics on the West African Monsoon

NASA Astrophysics Data System (ADS)

Ajoku, O.; Norris, J. R.; Miller, A. J.

2017-12-01

Seasonal biomass burning and resulting black carbon (BC) emissions have been well documented to effect regional weather patterns, especially including low level convection. These effects can be due to the hydrophilic and radiative qualities of the aerosols emitted from such burning. This project focuses on utilizing observation and reanalysis data in order to understand the effects of BC advected from the Southern hemisphere impact the dynamics of the West African Monsoon. Our results show that, of all monsoon months, BC advection has a direct impact on precipitation in July. Early analysis indicates that biomass burning occuring near Angola/Congo advects over the Gulf of Guinea, towards the Intertropical Convergence Zone at around 850mb and stabalizes the atmosphere. For a broader impact, this region is home to more than 200 million people and thus understanding these climate patterns may carry great importance.

Perspectives on Fire Research Collaboration in Siberia: What Have We Learned; Why Does It Matter; and Where Do We Go from Here?

NASA Astrophysics Data System (ADS)

Conard, S. G.

2010-12-01

My first experience of the vast taiga forests of Russia, and my first chance to meet and work with Russian fire researchers, was at a 1993 conference and field experiment planned jointly by Johann G. Goldammer from Germany and Valentin V. Furyaev from Russia. This meeting was the beginning of a long and fruitful collaboration among US, Canadian, and Russian fire scientists. We all became increasingly aware of the global signifiance of the circumpolar boreal zone, and of the need for better information on the extent and effects of boreal fires. Wildfires are the dominant disturbance regime in the Russian boreal zone, burning 10 to 20 million hectares per year. These fires are a significant source of CO2 and other greenhouse gases and aerosols. Our research team published some of the first remote-sensing based estimates of the extent of fire in Russia and of the potential variability in emissions that could result from different burning conditions. Through a series of 20 prescribed burns we were able to mimic a wide range of burning conditions and obtain information on the impacts on soils, vegetation, and fuel consumption. Based on these experimental fires, we have modeled the effects of weather and fuels on fuel consumption and other factors, and related fire characteristics to emissions, carbon stocks, and soil and vegetation processes. For the past 10 years, we have focused on the ecosystem effects of fires of varying severity in the Scots pine and mixed larch forests of central Siberia, on improved remote-sensing based estimates of burned area and fire effects, and on relating fire weather indices to fire potential and fuel consumption. Logging is an increasingly important disturbance in Russia’s forests, and logged sites, with their high fuel loads seem particularly susceptible to fire. We are currently studying interactions between logging and fire, with an emphasis on the differences in fuel consumption, emissions, and carbon stocks when fires burn in logged and unlogged areas. Fire activity and emissions are projected to increase substantially in the boreal zone as climate warms. We are currently working to develop a 30-yr fire record for Siberia based on satellite data. We will integrate these data with historic fire weather, emissions, and vegetation data to estimate fuel consumption and emissions from fires in Siberia from 1980 to 2010. We will reconstruct past fire regimes using dendrochronology data for selected sub-regions. The relationships derived through this work will provide a basis for projecting the future effects of changing climate on fire patterns, emissions and carbon cycle in Siberia. This project will provide critical information for input to global change models and for analysis of the regional and global impacts of changing fire regimes in the boreal zone.

Effect of slow energy releasing on divergent detonation of Insensitive High Explosives

NASA Astrophysics Data System (ADS)

Hu, Xiaomian; Pan, Hao; Huang, Yong; Wu, Zihui

2014-03-01

There exists a slow energy releasing (SER) process in the slow reaction zone located behind the detonation wave due to the carbon cluster in the detonation products of Insensitive High Explosives (IHEs), and the process will affect the divergent detonation wave's propagation and the driving process of the explosives. To study the potential effect, a new artificial burn model including the SER process based on the programmed burn model is proposed in the paper. Quasi-steady analysis of the new model indicates that the nonlinearity of the detonation speed as a function of front curvature owes to the significant change of the reaction rate and the reaction zone length at the sonic state. What's more, in simulating the detonation of IHE JB-9014, the new model including the slow reaction can predict a slower jump-off velocity, in good agreement with the result of the test.

Effect of primary-zone water injection on pollutants from a combustor burning liquid ASTM A-1 and vaporized propane fuels

NASA Technical Reports Server (NTRS)

Ingebo, R. D.; Norgren, C. T.

1973-01-01

A combustor segment 0.457 meter (18 in.) long with a maximum cross section of 0.153 by 0.305 meter (6 by 12 in.) was operated at inlet-air temperatures of 590 and 700 K, inlet-air pressures of 4 and 10 atmospheres, and fuel-air ratios of 0.014 and 0.018 to determine the effect of primary-zone water injection on pollutants from burning either propane or ASTM A-1 fuel. At a simulated takeoff condition of 10 atmospheres and 700 K, multiple-orifice nozzles used to inject water at 1 percent of the airflow rate reduced nitrogen oxides 75 percent with propane and 65 percent with ASTM A-1 fuel. Although carbon monoxide and unburned hydrocarbons increased with water injection, they remained relatively low; and smoke numbers were well below the visibility limit.

L-form plastics in the treatment of post-burn trophic ulcers and cicatrices of the foot calcaneal area.

PubMed

Shakirov, Babur M; Tagaev, Komil R; Tursunov, Bachron S; Achtamov, Dgamshed A

2009-03-01

The burn trauma of the posterior surface of calcaneus region and ankle joint followed by cicatrix formation in the Achilles tendon zone is often complicated by unhealing trophic ulcers. Eleven patients (seven men and four women, aged 9-54 years) have been operated on under our observation for prolonged unhealing ulcers and cicatrices located in the Achilles tendon zone. After cicatrices dissection, L-form plastic surgery was performed. The postoperative period was smooth; a skin graft was appropriately fixed to the proper tissues and the wound margins. Good results were achieved in 10 cases, and no complications were noted. However, in only one patient a marginal necrosis of the external talus part adjoining the ulcer due to tissue changes has been noted, but that had no influence on the good results of the operation.

[Cement burns: a 10-year retrospective study in our burn unit. About 55 cases].

PubMed

Besset, M; Quignon, R; Dhennin, C; Yassine, A; Penaud, A

2014-06-01

Although cement burns represents only a small percentage of admissions to burn centers, their diagnosis and treatment are specific. Our retrospective study concerns all patients treated for cement burns in our unit between 1999 and 2009. This is the largest series described. Fifty-five patients, aged from 23 to 63, were treated in our burn unit from 1999 to 2009. A review of medical and socioeconomic data was made from computer data files. This population is predominantly male, young and active. These burns occurred mainly in a domestic accident situation (78.2%). Burns were limited but deep and concerned especially lower limbs. The average duration of treatment was 39days. Forty-four patients were treated medically. The mean duration of sick live for these patients was 63 days. It was only of 21 days for those treated surgically. Aesthetic and functional sequelae were present in 88% of medically treated patients and in 18% of patients treated surgically. This study demonstrates that early surgical diagnosis and the coverage (care) of these burns allows to limit the socioeconomic echo and to reduce the risk of after-effects for this population of patients mainly young and active. The necessity of strengthening the precautionary measures with these users who are informed enough about the risks incurred during the misuse of the cement is also a reality. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Long term health-related quality of life after burns is strongly dependent on pre-existing disease and psychosocial issues and less due to the burn itself.

PubMed

Orwelius, L; Willebrand, M; Gerdin, B; Ekselius, L; Fredrikson, M; Sjöberg, F

2013-03-01

Health-related quality of life (HRQoL) is reduced after a burn, and is affected by coexisting conditions. The aims of the investigation were to examine and describe effects of coexisting disease on HRQoL, and to quantify the proportion of burned people whose HRQoL was below that of a reference group matched for age, gender, and coexisting conditions. A nationwide study covering 9 years and examined HRQoL 12 and 24 months after the burn with the SF-36 questionnaire. The reference group was from the referral area of one of the hospitals. The HRQoL of the burned patients was below that of the reference group mainly in the mental dimensions, and only single patients were affected in the physical dimensions. The factor that significantly affected most HRQoL dimensions (n=6) after the burn was unemployment, whereas only smaller effects could be attributed directly to the burn. Poor HRQoL was recorded for only a small number of patients, and the decline were mostly in the mental dimensions when compared with a group adjusted for age, gender, and coexisting conditions. Factors other than the burn itself, such as mainly unemployment and pre-existing disease, were most important for the long term HRQoL experience in these patients. Copyright © 2012 Elsevier Ltd and ISBI. All rights reserved.

Burn severity estimation using GeoEye imagery, object-based image analysis (OBIA), and Composite Burn Index (CBI) measurements

NASA Astrophysics Data System (ADS)

Dragozi, E.; Gitas, Ioannis Z.; Stavrakoudis, Dimitris G.; Minakou, C.

2015-06-01

Forest fires greatly influence the stability and functions of the forest ecosystems. The ever increasing need for accurate and detailed information regarding post-fire effects (burn severity) has led to several studies on the matter. In this study the combined use of Very High Resolution (VHR) satellite data (GeoEye), Objectbased image analysis (OBIA) and Composite Burn Index (CBI) measurements in estimating burn severity, at two different time points (2011 and 2012) is assessed. The accuracy of the produced maps was assessed and changes in burn severity between the two dates were detected using the post classification comparison approach. It was found that the produced burn severity map for 2011 was approximately 10% more accurate than that of 2012. This was mainly attributed to the increased heterogeneity of the study area in the second year, which led to an increased number of mixed class objects and consequently made it more difficult to spectrally discriminate between the severity classes. Following the post-classification analysis, the severity class changes were mainly attributed to the trees' ability to survive severe fire damage and sprout new leaves. Moreover, the results of the study suggest that when classifying CBI-based burn severity using VHR imagery it would be preferable to use images captured soon after the fire.

Numerical research of reburning-process of burning of coal-dust torch

NASA Astrophysics Data System (ADS)

Trinchenko, Alexey; Paramonov, Aleksandr; Kadyrov, Marsel; Koryabkin, Aleksey

2017-10-01

This work is dedicated to numerical research of ecological indicators of technological method of decrease in emissions of nitrogen oxides at combustion of solid fuel in coal-dust torch to improve the energy efficiency of steam boilers. The technology of step burning with additional input in zone of the maximum concentration of pollutant of strongly crushed fuel for formation of molecular nitrogen on surface of the burning carbon particles is considered. Results of modeling and numerical researches of technology, their analysis and comparison with the experimental data of the reconstructed boiler are given. Results of work show that input of secondary fuel allows to reduce emissions of nitrogen oxides by boiler installation without prejudice to its economic indicators.

Method for control of subsurface coal gasification

DOEpatents

Komar, Charles A.

1976-12-14

The burn front in an in situ underground coal gasification operation is controlled by utilizing at least two parallel groups of vertical bore holes disposed in the coalbed at spaced-apart locations in planes orthogonal to the plane of maximum permeability in the coalbed. The combustion of the coal is initiated in the coalbed adjacent to one group of the bore holes to establish a combustion zone extending across the group while the pressure of the combustion supporting gas mixture and/or the combustion products is regulated at each well head by valving to control the burn rate and maintain a uniform propagation of the burn front between the spaced-apart hole groups to gasify virtually all the coal lying therebetween.

First-aid with warm water delays burn progression and increases skin survival.

PubMed

Tobalem, M; Harder, Y; Tschanz, E; Speidel, V; Pittet-Cuénod, B; Wettstein, R

2013-02-01

First aid treatment for thermal injuries with cold water removes heat and decreases inflammation. However, perfusion in the ischemic zone surrounding the coagulated core can be compromised by cold-induced vasoconstriction and favor burn progression. The aim of this study is to evaluate the effect of local warming on burn progression in the rat comb burn model. 24 male Wistar rats were randomly assigned to either no treatment (control) or application of cold (17 °C) or warm (37 °C) water applied for 20 min. Evolution of burn depth, interspace necrosis, and microcirculatory perfusion were assessed with histology, planimetry, respectively with Laser Doppler flowmetry after 1 h, as well as 1, 4, and 7 days. Consistent conversion from a superficial to a deep dermal burn within 24 h was obtained in control animals. Warm and cold water significantly delayed burn depth progression, however after 4 days the burn depth was similar in all groups. Interspace necrosis was significantly reduced by warm water treatment (62±4% vs. 69±5% (cold water) and 82±3% (control); p<0.05). This was attributed to the significantly improved perfusion after warming, which was present 1 h after burn induction and was maintained thereafter (103±4% of baseline vs. 91±3% for cold water and 80±2% for control, p<0.05). In order to limit damage after burn injury, burn progression has to be prevented. Besides delaying burn progression, the application of warm water provided an additional benefit by improving the microcirculatory perfusion, which translated into increased tissue survival. Copyright © 2012 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Behavior of Explosives Under Pressure in a Diamond Anvil Cell

DOE Office of Scientific and Technical Information (OSTI.GOV)

Foltz, M F

2006-06-20

Diamond anvil cell (DAC) studies can yield information about the pressure dependence of materials and reactions under conditions comparable to shock loading. The pressure gradient across the face of the diamonds is often deliberately minimized to create uniform pressure over much of the sample and a simplified data set. To reach very high pressures (30-40 GPa), however, it may be necessary to use ''softer'', high nitrogen content diamonds that are more susceptible to bending under pressure. The resulting enhanced pressure gradient then provides a view of high-pressure behavior under anisotropic conditions similar to those found at the burn front inmore » a bulk sample. We discuss visual observations of pressure-induced changes relative to variations in burn rate of several explosives (Triaminotrinitrobenzene, Nitromethane, CL-20) in the DAC. The burn rate behavior of both Nitromethane (NM) and Triaminotrinitrobenzene (TATB) were previously reported for pressures up to {approx}40 GPa. Nitromethane showed a near monotonic increase in burn rate to a maximum at {approx}30 GPa after which the burn rate decreased, all without color change. At higher pressures, the TATB samples had shiny (metallic) polycrystalline zones or inclusions where the pressure was highest in the sample. Around the shiny zones was a gradation of color (red to yellow) that appeared to follow the pressure gradient. The color changes are believed related to disturbances in the resonance structure of this explosive as the intermolecular separations decrease with pressure. The color and type of residue found in unvented gaskets after the burn was complete also varied with pressure. The four polymorphs of CL-20 ({alpha}, {beta}, {gamma}, {var_epsilon}-Hexanitrohexaazaisowurtzitane, HNIW) did not change color up to the highest pressure applied ({approx}30 GPa), and each polymorph demonstrated a distinctly different burn rate signature. One polymorph {beta} was so sensitive to laser ignition over a narrow pressure range that the sample could not be aligned with a low power laser without ignition. The burn rate for that one polymorph could only be measured at pressures above and below that unique pressure. This anomalous ignition threshold is discussed with respect to the matrix of possible polymorphs, most of which have not been isolated in the laboratory. The changes in behavior, color and reaction rates of all samples are discussed with respect to possible implications to chemistry at high pressure.« less

Potentials and limitations of remote fire monitoring in protected areas.

PubMed

Dos Santos, João Flávio Costa; Romeiro, Joyce Machado Nunes; de Assis, José Batuíra; Torres, Fillipe Tamiozzo Pereira; Gleriani, José Marinaldo

2018-03-01

Protected areas (PAs) play an important role in maintaining the biodiversity and ecological processes of the site. One of the greatest challenges for the PA management in several biomes in the world is wildfires. The objective of this work was to evaluate the potentialities and limitations of the use of data obtained by orbital remote sensing in the monitoring fire occurrence in PAs. Fire Occurrence Records (FORs) were analyzed in Serra do Brigadeiro State Park, Minas Gerais, Brazil, from 2007 to 2015, using photo interpreted data from TM, ETM + and OLI sensors of the Landsat series and the Hot Spot Database (HSD) from the Brazilian Institute of Space Research - INPE. It was also observed the time of permanence of the scar left by fire on the landscape, through the multitemporal analysis of the behavior of NDVI (Normalized Difference Vegetation Index) and NBR (Normalized Burn Ratio) indexes, before and after the occurrence. The greatest limitation found for the orbital remote monitoring was the presence of clouds in the passage of the sensor in dates close to the occurrence of the fires. The burned area identified by photo interpretation was 54.9% less than the area contained in the FOR. Although the HSD reported fire occurrences in the buffer zone (up to 10km from the Park), no FORs were found at a distance greater than 1100m from the boundaries of the PA. As the main potential of remote sensing, the possibility of identifying burned areas throughout the park and surroundings is highlighted, with low costs and greater accuracy. Copyright © 2017 Elsevier B.V. All rights reserved.

Phosphorus release from ash and remaining tissues of two wetland species after a prescribed fire.

PubMed

Liu, G D; Gu, B; Miao, S L; Li, Y C; Migliaccio, K W; Qian, Y

2010-01-01

Dead plant tissues and ash from a prescribed fire play an important role in nutrient balance and cycling in the Florida Everglades ecosystem. The objective of this study was to assess the dynamic changes in total phosphorus release (TPr) from ash or tissues of either cattail (Typha domingensis Pers.) or sawgrass (Cladium jamaicense Crantz) to water. Natural-dead (senesced-dead) and burning-dead (standing-dead due to a prescribed fire) cattail and sawgrass were collected from highly (H) and moderately (M) impacted zones in the Florida Everglades. This experiment was conducted by incubation and water-extraction of the materials in plastic bottles for 65 d at room temperature (24 +/- 1 degrees C). Results showed that 63 to 88%, 17 to 48%, 9 to 20%, and 13 to 28% of total P (TPp) were released as TPr from cattail and sawgrass ash, cattail tissues from the H zone, cattail tissues, and sawgrass tissues from the M zone, respectively. TPp means total P of plant tissues, whereas TPr is total P release from the tissues or ash. Most of the TPr was released within 24 h after burning. The quick release of TPr observed in this experiment may help explain the P surge in the surface water immediately following a fire in the marsh. These findings suggest that prescribed burning accelerates P release from cattail and sawgrass. They also imply that it is very important to keep the water stagnant in the first 24 h to maximize the benefits of a prescribed fire in the Everglades.

Evolution of massive stars in very young clusters and associations

NASA Technical Reports Server (NTRS)

Stothers, R. B.

1985-01-01

Statistics concerning the stellar content of young galactic clusters and associations which show well defined main sequence turnups have been analyzed in order to derive information about stellar evolution in high-mass galaxies. The analytical approach is semiempirical and uses natural spectroscopic groups of stars on the H-R diagram together with the stars' apparent magnitudes. The new approach does not depend on absolute luminosities and requires only the most basic elements of stellar evolution theory. The following conclusions are offered on the basis of the statistical analysis: (1) O-tupe main-sequence stars evolve to a spectral type of B1 during core hydrogen burning; (2) most O-type blue stragglers are newly formed massive stars burning core hydrogen; (3) supergiants lying redward of the main-sequence turnup are burning core helium; and most Wolf-Rayet stars are burning core helium and originally had masses greater than 30-40 solar mass. The statistics of the natural spectroscopic stars in young galactic clusters and associations are given in a table.

Changes in orchid populations and endophytic fungi with rainfall and prescribed burning in Pterostylis revoluta in Victoria, Australia.

PubMed

Jasinge, N U; Huynh, T; Lawrie, A C

2018-02-12

Wildfires are common in seasonally dry parts of the world with a Mediterranean climate. Prescribed burning is used to reduce fuel load and fire risk, but often without reliable information on its effects. This study investigated the effects of prescribed burns in different seasons on Pterostylis revoluta, an autumn-flowering Australian terrestrial orchid, and its orchid mycorrhizal fungi (OMFs) to find the least damaging season for a prescribed burn. Burns were conducted mid-season in spring and summer 2011 and autumn and winter 2012. Orchids were enumerated and measured during their flowering season in autumn 2011-2014 and mycorrhizal fungi were isolated before and after the burns in autumn 2011, 2012 and 2014. Micro-organisms isolated were characterized. DNA was extracted from the OMFs, and the internal transcribed spacer region was amplified by PCR. Amplicons were clustered by restriction fragment length polymorphism (RFLP), and representative amplicons were sequenced. OMF were tested for sensitivity to smoke water. The number of plants increased up to 4-fold and 90 % of plants became vegetative during this study. Isolation of mycorrhizal fungi increased and isolation of bacteria decreased. Before the burns, the main OMF isolated was unexpectedly Tulasnella calospora (Boud.) Juel. By 2014, after the burns, the expected Ceratobasidium sp. D.P. Rogers was the only OMF isolated in most burnt quadrats, whereas T. calospora was confined to a minority of unburnt 'control' and the 'spring burn' quadrats, which were also the only ones with flowering plants. The decline in rainfall during 2010-2012 probably caused the switch from mainly flowering to mainly vegetative plants and the change in OMFs. Burning in spring to summer was less damaging to this orchid than burning in autumn to winter, which should be noted by authorities in fire management plans for fire-prone areas in which this orchid occurs. © The Author(s) 2018. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The Betelgeuse Project II: Asteroseismology

NASA Astrophysics Data System (ADS)

Nance, S.; Sullivan, J. M.; Diaz, M.; Wheeler, J. Craig

2018-06-01

We explore the question of whether the interior state of massive red supergiant supernova progenitors can be effectively probed with asteroseismology. We have computed a suite of ten models with ZAMS masses from 15 to 25 M⊙ in intervals of 1 M⊙ including the effects of rotation, with the stellar evolutionary code MESA. We estimate characteristic frequencies and convective luminosities of convective zones at two illustrative stages, core helium burning and off-center convective carbon burning. We also estimate the power that might be delivered to the surface to modulate the luminous output considering various efficiencies and dissipation mechanisms. The inner convective regions should generate waves with characteristic periods of ˜ 20 days in core helium burning, ˜10 days in helium shell burning, and 0.1 to 1 day in shell carbon burning. Acoustic waves may avoid both shock and diffusive dissipation relatively early in core helium burning throughout most of the structure. In shell carbon burning, years before explosion, the signal generated in the helium shell might in some circumstances be weak enough to avoid shock dissipation, but is subject to strong thermal dissipation in the hydrogen envelope. Signals from a convective carbon-burning shell are very likely to be even more severely damped by within the envelope. In the most optimistic case, early in core helium burning, waves arriving close to the surface could represent luminosity fluctuations of a few millimagnitudes, but the conditions in the very outer reaches of the envelope suggest severe thermal damping there.

Interstitial lung disease due to fumes from heat-cutting polymer rope.

PubMed

Sharman, P; Wood-Baker, R

2013-09-01

Interstitial lung disease (ILD) due to inhalation of fume/smoke from heating or burning of synthetic polymers has not been reported previously. A fish farm worker developed ILD after cutting rope (polypropylene and nylon) for about 2 hours per day over an extended period using an electrically heated 'knife'. This process produced fume/smoke that entered the workers breathing zone. No other likely cause was identified. This case suggests that exposure to airborne contaminants generated by the heating or burning of synthetic polymers has the potential to cause serious lung disease.

Topical Application of Honey for Burn Wound Treatment - an Overview

PubMed Central

Subrahmanyam, M.

2007-01-01

Summary The use of honey in the treatment of burn wounds is discussed and an attempt is made to assess honey's current status as a burn wound dressing. Various kinds of honey are considered, as also the history of its use for this purpose since ancient times. The scientific reasons for honey's appropriateness in burns treatment are reviewed and an account is provided of the main benefits of such treatment. PMID:21991084

Climatic Zones, Soil Moisture Seasonality and Biomass Burning and Their Influence On Ozone Precursor Concentrations Over West Africa as Retrieved from Satellites

NASA Astrophysics Data System (ADS)

Onojeghuo, A. R.; Balzter, H.; Monks, P. S.

2015-12-01

West Africa is a region with six different climatic zones including a rich savannah affected by biomass burning annually, the Niger delta oil producing region with major gas flaring sites and a long coastline. Research on atmospheric pollution using remotely sensed data over West Africa has mostly been conducted at regional scale or for individual countries, with little emphasis on the dynamics of climatic zones and the diversity of land cover types. This study analyses annual seasonal dynamics of emissions of two ozone precursors stratified by climatic zone: nitrogen dioxide (NO2) from OMI and carbon monoxide (CO) from TES. The different sources of these pollutants and their seasonality are explicitly considered. Results indicate that the highest annual wet season NO2 column concentrations were in the semi-arid zone (1.33 x 1015 molecules cm-2) after prolonged periods of low soil moisture while the highest dry season were observed in the wet sub-humid zone (2.62 x 1015 molecules cm-2) where the savannah fires occur annually. The highest annual CO concentrations (> 3.1 x 1018 molecules cm-2) were from the Niger Delta, located in the humid zone. There were indications of atmospheric transport of CO from the southern hemisphere in the west season. Climate change induced soil moisture variability was most prominent in the dry sub-humid and semi-arid climatic zones (±0.015m3m-3) . The causal effects of soil moisture variability on NO2 emissions and their seasonal cycles were tested using the Granger causality test. Causal effects of inter-zonal exchanges/transport of NO2 and CO emissions respectively were inferred using Directed Acyclic Graphs. The results indicate that NO2, CO and their seasonal ratios are strongly affected by changes in soil moisture.

[Advances in the research of pressure therapy for pediatric burn patients with facial scar].

PubMed

Wei, Y T; Fu, J F; Li-Tsang, Z H P

2017-05-20

Facial scar and deformation caused by burn injury severely affect physical and psychological well-being of pediatric burn patients, which needs medical workers and pediatric burn patients' family members to pay much attention to and to perform early rehabilitation treatment. Pressure therapy is an important rehabilitative strategy for pediatric burn patients with facial scar, mainly including wearing headgears and transparent pressure facemasks, which have their own features. To achieve better treatment results, pressure therapy should be chosen according to specific condition of pediatric burn patients and combined with other assistant therapies. Successful rehabilitation for pediatric burn patients relies on cooperation of both family members of pediatric burn patients and society. Rehabilitation knowledge should be provided to parents of pediatric burn patients to acquire their full support and cooperation in order to achieve best therapeutic effects and ultimately to rebuild physical and psychological well-being of pediatric burn patients.

Experimental and Modeling Investigation of the Effect of Air Preheat on the Formation of NOx in an RQL Combustor

NASA Technical Reports Server (NTRS)

Samuelsen, G. S.; Brouwer, J.; Vardakas, M. A.; Holderman, J. D.

2012-01-01

The Rich-burn/Quick-mix/Lean-burn (RQL) combustor concept has been proposed to minimize the formation of oxides of nitrogen (NOx) in gas turbine systems. The success of this low-NOx combustor strategy is dependent upon the links between the formation of NOx, inlet air preheat temperature, and the mixing of the jet air and fuel-rich streams. Chemical equilibrium and kinetics modeling calculations and experiments were performed to further understand NOx emissions in an RQL combustor. The results indicate that as the temperature at the inlet to the mixing zone increases (due to preheating and/or operating conditions) the fuel-rich zone equivalence ratio must be increased to achieve minimum NOx formation in the primary zone of the combustor. The chemical kinetics model illustrates that there is sufficient residence time to produce NOx at concentrations that agree well with the NOx measurements. Air preheat was found to have very little effect on mixing, but preheating the air did increase NOx emissions significantly. By understanding the mechanisms governing NOx formation and the temperature dependence of key reactions in the RQL combustor, a strategy can be devised to further reduce NOx emissions using the RQL concept.

Combustion Limits and Efficiency of Turbojet Engines

NASA Technical Reports Server (NTRS)

Barnett, H. C.; Jonash, E. R.

1956-01-01

Combustion must be maintained in the turbojet-engine combustor over a wide range of operating conditions resulting from variations in required engine thrust, flight altitude, and flight speed. Furthermore, combustion must be efficient in order to provide the maximum aircraft range. Thus, two major performance criteria of the turbojet-engine combustor are (1) operatable range, or combustion limits, and (2) combustion efficiency. Several fundamental requirements for efficient, high-speed combustion are evident from the discussions presented in chapters III to V. The fuel-air ratio and pressure in the burning zone must lie within specific limits of flammability (fig. 111-16(b)) in order to have the mixture ignite and burn satisfactorily. Increases in mixture temperature will favor the flammability characteristics (ch. III). A second requirement in maintaining a stable flame -is that low local flow velocities exist in the combustion zone (ch. VI). Finally, even with these requirements satisfied, a flame needs a certain minimum space in which to release a desired amount of heat, the necessary space increasing with a decrease in pressure (ref. 1). It is apparent, then, that combustor design and operation must provide for (1) proper control of vapor fuel-air ratios in the combustion zone at or near stoichiometric, (2) mixture pressures above the minimum flammability pressures, (3) low flow velocities in the combustion zone, and (4) adequate space for the flame.

The effects of fire on ant trophic assemblage and sex allocation

PubMed Central

Caut, Stephane; Jowers, Michael J; Arnan, Xavier; Pearce-Duvet, Jessica; Rodrigo, Anselm; Cerda, Xim; Boulay, Raphaël R

2014-01-01

Fire plays a key role in ecosystem dynamics worldwide, altering energy flows and species community structure and composition. However, the functional mechanisms underlying these effects are not well understood. Many ground-dwelling animal species can shelter themselves from exposure to heat and therefore rarely suffer direct mortality. However, fire-induced alterations to the environment may change a species' relative trophic level within a food web and its mode of foraging. We assessed how fire could affect ant resource utilization at different scales in a Mediterranean forest. First, we conducted isotopic analyses on entire ant species assemblages and their potential food resources, which included plants and other arthropods, in burned and unburned plots 1 year postfire. Second, we measured the production of males and females by nests of a fire-resilient species, Aphaenogaster gibbosa, and analyzed the differences in isotopic values among workers, males, and females to test whether fire constrained resource allocation. We found that, in spite of major modifications in biotic and abiotic conditions, fire had little impact on the relative trophic position of ant species. The studied assemblage was composed of species with a wide array of diets. They ranged from being mostly herbivorous to completely omnivorous, and a given species' trophic level was the same in burned and unburned plots. In A. gibbosa nests, sexuals had greater δ15N values than workers in both burned and unburned plots, which suggests that the former had a more protein-rich diet than the latter. Fire also appeared to have a major effect on A. gibbosa sex allocation: The proportion of nests that produced male brood was greater on burned zones, as was the mean number of males produced per nest with the same reproductive investment. Our results show that generalist ants with relatively broad diets maintained a constant trophic position, even following a major disturbance like fire. However, the dramatically reduced production of females on burned zones compared to unburned zones 1 year postfire may result in considerably reduced recruitment of new colonies in the mid to long term, which could yield genetic bottlenecks and founder effects. Our study paves the way for future functional analyses of fire-induced modifications in ant populations and communities. PMID:24455159

Rehabilitation of fire-damaged forest lands in southwestern Maine

Treesearch

A. D. Nutting; James C. Rettie; Wayne G. Banks

1949-01-01

Recognizing that it can ill afford the loss of timber productivity on the large acreage of forest land burned over by the 1947 fires, the state of Maine requested assistance of the Northeastern Forest Experiment Station of the United States Forest Service in a program of research that would aid in the rehabilitation of the burned-over forest land.

Burden of burns in Portugal, 2000-2013: A clinical and economic analysis of 26,447 hospitalisations.

PubMed

Santos, João V; Oliveira, Andreia; Costa-Pereira, Altamiro; Amarante, José; Freitas, Alberto

2016-06-01

There is a lack of recent and nation-wide epidemiological studies of burns in Europe, mainly in southern Europe. There are no recent studies describing the clinical and economic burden of burns in this European area. Hence, this research aimed to describe the clinical and economic burden of burn hospitalisations in Portugal. A retrospective observational study was performed and the Portuguese hospitalisation database of public hospitals was used; all inpatients, discharged between 2000 and 2013, with a main or secondary diagnosis of burns (ICD-9-CM: 940.xx-949.xx) were taken into account. Furthermore, admissions to hospitals with and without burn centres were compared. A total of 26,447 burn hospitalisations were registered (mean of 1889burn admissions/year). The total hospitalisation rate was of 18.9hospitalisations/100,000inhabitants/year, and there was a higher incidence of male patients. Burn hospitalisations and hospitalisation rates are significantly decreasing - mostly in 0-14-year-old patients - and children below the age of 5 years represented a fifth of all admissions. Besides the important morbidity, the in-hospital mortality rate was of 4.4%. With a total annual charge of almost 13million Euros, the average cost per burn admission is increasing, and reached 8032Euros in 2013. Additionally, more than half of the patients admitted to hospitals without burn centres were not transferred to hospitals with burn centres, not following the European Burns Association transferral criteria. As the largest southern European nation-wide epidemiological study of burn patients, this research highlights that burn admissions, as well as hospitalisation rates, are decreasing significantly. This was particularly obvious among the youngest patients despite the fact that the numbers still remain very high. Moreover, the in-hospital mortality rate is still excessively high and the burn transferral criteria are not being followed. Thus, it is important to improve preventive measures, reach out to and educate providers about the burn transferral criteria, and develop specific health care strategies for children with these injuries. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

Stably operating pulse combustor and method

DOEpatents

Zinn, Ben T.; Reiner, David

1990-01-01

A pulse combustor apparatus adapted to burn either a liquid fuel or a pulverized solid fuel within a preselected volume of the combustion chamber. The combustion process is substantially restricted to an optimum combustion zone in order to attain effective pulse combustion operation.

Cyclic flow underground coal gasification process

DOEpatents

Bissett, Larry A.

1978-01-01

The present invention is directed to a method of in situ coal gasification for providing the product gas with an enriched concentration of carbon monoxide. The method is practiced by establishing a pair of combustion zones in spaced-apart boreholes within a subterranean coal bed and then cyclically terminating the combustion in the first of the two zones to establish a forward burn in the coal bed so that while an exothermic reaction is occurring in the second combustion zone to provide CO.sub.2 -laden product gas, an endothermic CO-forming reaction is occurring in the first combustion zone between the CO.sub.2 -laden gas percolating thereinto and the hot carbon in the wall defining the first combustion zone to increase the concentration of CO in the product gas. When the endothermic reaction slows to a selected activity the roles of the combustion zones are reversed by re-establishing an exothermic combustion reaction in the first zone and terminating the combustion in the second zone.

20. Historic American Buildings Survey Albert S. Burns, Photographer September ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

20. Historic American Buildings Survey Albert S. Burns, Photographer September 30, 1935. MAIN ENTRANCE - SOUTH FACADE - The Maples, 630 South Carolina Avenue Southeast, Washington, District of Columbia, DC

Isolation and identification of burn wound superbugs by molecular technique and their susceptibility to silver nanoparticles

NASA Astrophysics Data System (ADS)

Mala, R.; Celsia, A. S. Ruby

2018-02-01

Burn wound is a global problem affecting millions of people. It is the major cause of mortality and morbidity. This study was aimed to isolate and identify the wound isolates by 16S rRNA and to assess their susceptibility to antibiotics and silver nanoparticles. Silver nanoparticles were synthesized using aqueous extract of A.indica. The silver nanoparticles were characterized by FESEM, XRD, FTIR and DSC. Antibacterial susceptibility of the isolates was assessed by well diffusion method. The wound isolates were identified as S.aureus and E.coli. Both isolates were resistant to β lactum antibiotics, aminoglycoside, quinolones and macrolides. The inhibition zone exhibited by all antibiotics against both organisms was less than 5 mm. The size of silver nanoparticles were recorded as 55 nm. XRD confirmed the crystalline nature of the nanoparticles. TGA and DSC of silver nanoparticles showed the loss of weight and the melting point of silver nanoparticles was recorded at 871.3°C. Silver nano particles inhibited S.aureus and E.coli with an inhibition zone of 27 mm and 32 mm respectively. Therefore the study demonstrated that only silver containing dressings can be used in burn wounds infected by multi drug resistant super bugs.

Social participation, social support, and body image in the first year of rehabilitation in burn survivors: A longitudinal, three-wave cross-lagged panel analysis using structural equation modeling.

PubMed

Ajoudani, Fardin; Jasemi, Madineh; Lotfi, Mojgan

2018-05-15

Psychosocial outcomes of burn survivors in the first year of rehabilitation are not well studied. Considering the interrelationships among psychosocial processes in burn survivors, we assessed three psychosocial variables (i.e., social support, social participation, and body image) simultaneously in a longitudinal study. This study aimed at identifying the developmental trajectory of the main study variables and also discovering the causal pathways between social support, body image, and social participation of burn survivors in the first year of rehabilitation. One hundred individuals were enrolled in the study. The analysis was based on three waves of data collected at the time of discharge, 6 months after discharge, and 12 months after discharge. We used MSPSS, SWAP, and the p-scale for measuring the variables social support, body image, and social participation, respectively. A repeated-measures analysis of variance (ANOVA) was performed to identify the major differences in the mean levels of the main study variables across the three evaluation times. A structural equation modeling (SEM) approach was implemented in four hypothesized cross-lagged models (M1, M2, M3, and M4) to evaluate the bidirectional relationships among the main variables. All hypothesized models were tested, and their goodness-of-fit indexes were compared to identify the best fitting model. All three main variables worsen during the first six months after burn and then do not return to their earlier level. The M4 (final model) chosen to represent the data showed the best goodness-of-fit indexes (χ 2 (9)=51.76, p<.01, RMSEA=0.060, IFI=0.97, and CFI=0.98) among all hypothesized models. The effect of social participation on body image, and vice versa, seems to be relatively constant and steady. Social support at the time of discharge predicted social participation at 12 months after burn, with the relationship mediated by body image at 6 months after burn. Our study findings suggest that persistent care should be provided for burn survivors even after discharge. Copyright © 2018 Elsevier Ltd and ISBI. All rights reserved.

Local biomass burning is a dominant cause of the observed precipitation reduction in southern Africa

PubMed Central

Hodnebrog, Øivind; Myhre, Gunnar; Forster, Piers M.; Sillmann, Jana; Samset, Bjørn H.

2016-01-01

Observations indicate a precipitation decline over large parts of southern Africa since the 1950s. Concurrently, atmospheric concentrations of greenhouse gases and aerosols have increased due to anthropogenic activities. Here we show that local black carbon and organic carbon aerosol emissions from biomass burning activities are a main cause of the observed decline in southern African dry season precipitation over the last century. Near the main biomass burning regions, global and regional modelling indicates precipitation decreases of 20–30%, with large spatial variability. Increasing global CO2 concentrations further contribute to precipitation reductions, somewhat less in magnitude but covering a larger area. Whereas precipitation changes from increased CO2 are driven by large-scale circulation changes, the increase in biomass burning aerosols causes local drying of the atmosphere. This study illustrates that reducing local biomass burning aerosol emissions may be a useful way to mitigate reduced rainfall in the region. PMID:27068129

Persistent Influences of the 2002 Hayman Fire on Stream Nitrate and Dissolved Organic Carbon

NASA Astrophysics Data System (ADS)

Rhoades, C.; Pierson, D. N.; Fegel, T. S., II; Chow, A. T.; Covino, T. P.

2016-12-01

Large, high severity wildfires alter the physical and biological conditions that determine how watersheds retain and release nutrients and regulate stream water quality. For five years after the 2002 Hayman Fire burned in Colorado conifer forests, stream nitrate concentrations and export increased steadily in watersheds with extensive high-severity burning. Stream temperature and turbidity also increased in relation to the extent of high-severity burning and remained elevated above background levels throughout the initial five year post-fire period. Our recent sampling documents that 14 years after the Hayman Fire stream nitrate remains an order of magnitude higher in extensively-burned (35-90%) compared to unburned watersheds (0.2 vs 2.8 mg L-1). Nitrate represents 83% of the total dissolved N in extensively-burned watersheds compared to 29% in unburned watersheds. In contrast, dissolved organic carbon (DOC), was highest in watersheds that burned to a moderate extent (10-20%) and lowest in those with extensive burning. Catchments with a moderate extent burned had DOC concentrations 2.5 and 1.7 times more than those with extensive burning and unburned catchments, respectively. Peak concentrations of DOC and nitrate track the rising limb of the streamflow hydrograph and reach a maximum in May, but patterns among burn extent categories were seasonally consistent. Current riparian conditions are linked to stream nitrate in burned watersheds. For example, stream nitrate increases proportionally to the extent of riparian zones with low shrub cover (R2 = 0.76). We found signs of watershed recovery compared to the initial post-fire period; stream temperature and turbidity remained elevated in extensively burned catchments, but increases were only significant during the spring season. The persistent stream nitrate concentrations as well as the relation between riparian cover and post-fire stream nitrate may help prioritize restoration planting efforts and mitigate chronic, elevated nitrate export from burned watersheds.

AmeriFlux US-CZ2 Sierra Critical Zone, Sierra Transect, Ponderosa Pine Forest, Soaproot Saddle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goulden, Michael

This is the AmeriFlux version of the carbon flux data for the site US-CZ2 Sierra Critical Zone, Sierra Transect, Ponderosa Pine Forest, Soaproot Saddle. Site Description - Half hourly data are available at https://www.ess.uci.edu/~california/. This site is one of four Southern Sierra Critical Zone Observatory flux towers operated along an elevation gradient (sites are USCZ1, USCZ2, USCZ3 and USCZ4). This site is an oak/pine forest, with occasional thinning and wildfire, a prescribed understory burn ~2012, and severe drought and ~80% canopy mortality in 2011-15

[Pay close attention to the quality of life of patients and look to the future of burn rehabilitation].

PubMed

Wu, Jun; Chen, Jian

2013-04-01

After 50 years' development, a rather comprehensive burn care system has been built up in China, and it has played key roles in wound healing and salvaging victims of burn trauma. Since survival is no longer the main priority of treatment, more efforts should be made to cut down the incidence of disabilities and to improve the quality of life of the survivors. The further progress on burn rehabilitation therapies, including functional improvement, psychological rehabilitation, aesthetic recovery, and occupational and social recuperation, would bring new perspectives to our burn care system.

[Development of Terahertz Imaging Technology in the Assessment of Burn Injuries].

PubMed

Zhu, Xinjian; He, Xuan; Wang, Pin; Gao, Dandan; Qiu, Yan; He, Qinghua; Wu, Baoming

2016-02-01

Terahertz waves have unique properties and advantages, which makes it gain increasing attention and applications in the biomedical field. Burns is a common clinical trauma. Since the water-sensitive and non-destructive characteristics of terahertz, terahertz imaging techniques can be used to detect burns. So far, terahertz imaging technology in the assessment of burn injuries has been developed from ex vivo to in vivo, and high-resolution images can be obtained through the gauzes and plasters. In this paper, we mainly introduces the application of terahertz imaging technology and development in the assessment of burn injuries.

Prescribed burning effects on summer elk forage availability in the subalpine zone, Banff National Park, Canada.

PubMed

Sachro, L L; Strong, W L; Gates, C C

2005-11-01

The effects of prescribed burning on forage abundance and suitability for elk (Cervus elaphus) during the snow-free season was evaluated in east-central Banff National Park, Canada. Six coniferous forest and mixed shrub-herb plant communities (n=144 plots), and 5223ha of burned (n=131) vegetation <12 years old were sampled using a stratified semi-random design. Sampling units represented various combinations of vegetation, terrain conditions, and stand ages that were derived from digital biophysical data, with plant communities the basic unit of analysis. Burning coniferous forest stands reduced woody biomass, and increased herbaceous forage from 146 to 790 kg/ha. Increases commonly occurred in the percent cover of hairy wild rye (Leymus innovatus (Beal) Pigler) and fireweed (Chamerion angustifolium (L.) Holub.). The herbaceous components of mixed shrub-herb communities increased from 336-747 kg/ha to 517-1104 kg/ha in response to burning (P<0.025, Mann-Whitney U-test). Browse biomass (mostly Salix spp. and Betula nana L.) increased >or=220% (P

Study of Reaction Mechanism in Tracer Munitions

DTIC Science & Technology

1974-12-01

Effect of Fuel Particle Size on Reaction Zone Thickness 39 10 Temperature Distribution in Solid 41 11 Computed Reaction Rates as Func’ion of Heat Flux...dissociation (cal/g) R = gan constant (cal/mole K) r radius of fuel droplet (cm) s or x = distance increments in solid phase (cm) T = surface temperature ...of solid (*K) S T = arerage temperature in the reaction zone (°K) a t = ti-ne (sec) tb = avaporation time for droplet (sec) v = regression or burning

Antibacterial activity of some bryophytes used traditionally for the treatment of burn infections.

PubMed

Singh, Meenakshi; Singh, Shweta; Nath, Virendra; Sahu, Vinay; Rawat, Ajay Kumar Singh

2011-05-01

Plagiochasma appendiculatum L. & L. (Aytoniaceae), Conocephalum conicum (L.) Necker (Conocephalaceae), Bryum argenteum Hedw. (Bryaceae), and Mnium marginatum (With.) P. Beauv. (Mniaceae) are bryophytes (liverworts and mosses) used by traditional healers for the treatment of burn, cuts, wounds, and skin disorders. This study evaluated the antibacterial activity of four bryophytes against some common bacteria responsible for burn infections. Different fractions of bryophytes were screened using the disc diffusion (qualitative) and broth microdilution (quantitative) methods, according to the guidelines of the National Committee for Clinical and Laboratory Standards. Chloroform fractions of liverworts were more active against Gram negative strains while butanol fractions of mosses had significant activity against Gram positive bacteria. Staphylococcus aureus was the most sensitive strain of those tested with the butanol fraction of M. marginatum (moss), with the strongest inhibition zone of 102.92% and minimum inhibitory concentration of 30 μg mL(-1). Our findings support the use of the bryophytes in traditional medicine for burn infections because of their significant antibacterial activity.

H ingestion into He-burning convection zones in super-AGB stellar models as a potential site for intermediate neutron-density nucleosynthesis

DOE PAGES

Jones, Sam; Ritter, Christian; Herwig, Falk; ...

2015-12-03

We investigate the evolution of super-AGB (SAGB) thermal pulse (TP) stars for a range of metallicities (Z) and explore the effect of convective boundary mixing (CBM). With decreasing metallicity and evolution along the TP phase, the He-shell flash and the third dredge-up (TDU) occur closer together in time. After some time (depending upon the CBM parametrization), efficient TDU begins while the pulse-driven convection zone (PDCZ) is still present, causing a convective exchange of material between the PDCZ and the convective envelope. This results in the ingestion of protons into the convective He-burning pulse. Even small amounts of CBM encourage themore » interaction of the convection zones leading to transport of protons from the convective envelope into the He layer. H-burning luminosities exceed 10 9 (in some cases 10 10) L⊙. We also calculate models of dredge-out in the most massive SAGB stars and show that the dredge-out phenomenon is another likely site of convective-reactive H- 12C combustion. We discuss the substantial uncertainties of stellar evolution models under these conditions. Nevertheless, the simulations suggest that in the convective-reactive H-combustion regime of H ingestion the star may encounter conditions for the intermediate neutron capture process (i-process). We speculate that some CEMP-s/r stars could originate in i-process conditions in the H ingestion phases of low-Z SAGB stars. This scenario would however suggest a very low electron-capture supernova rate from SAGB stars. Here, we also simulate potential outbursts triggered by such H ingestion events, present their light curves and briefly discuss their transient properties.« less

Climate Change and Mountain Community Fire Management in the Cordillera Blanca, Peru

NASA Astrophysics Data System (ADS)

All, J.; Medler, M.; Cole, R. J.; Arques, S.; Schmitt, C. G.

2014-12-01

In the central Andes of Peru, climate change is altering fire risk through changes in local meteorology and fuel loading. Greater moisture and favorable growing conditions are increasing vegetative productivity, which in turn increases fuel loads. This process is accentuated during El Nino events and potentially results in increased fire occurrence and frequency during relatively dry La Nina events. Park officials are concerned about the ramification of the changes on local ecology and tourist use of the resources. However, using a time-series of two different products from the MODIS Terra and Aqua platforms (Active Fire and Burned Area), TRMM 3B43 precipitation data, and Multivariate ENSO Index data we document fire occurrence and extent from 2000 to 2010 and our analysis indicates that fires are burning exclusively during winter months when there are no natural ignition sources. Globally, fire is used in conjunction with grazing to improve the regeneration and yield of grasses. During our interviews, locals claimed to only set fires in the buffer zone outside of the park, but our analysis indicates that the buffer zone rarely burns and that most fires begin within the park and only occasionally move into the buffer zones. Additionally, we determined that although this is small-scale fire activity every year, overall fire is having a very minor effect on local systems. The park service must develop programs to work with local grazing stakeholders to better limit the impacts of fire, while also address the negative perceptions from tourists in the future. In this instance, fire perception and fire reality are not the same and the challenge for resource managers is how to reconcile these two factors in order to more effectively manage the parklands.

Trauma mechanisms and injury patterns in pediatric burn patients.

PubMed

Moehrlen, Theres; Szucs, Thomas; Landolt, Markus A; Meuli, Martin; Schiestl, Clemens; Moehrlen, Ueli

2018-03-01

The objective of this study was to evaluate the frequency, severity, exact patterns and mechanisms of burn injuries in children. The patient records of children with acute burns admitted to the University Children's Hospital of Zurich were retrospectively reviewed over an 11year period. The age group with the highest risk, were children under the age of five (69%). Boys were overrepresented in all age groups, but the gender imbalance increased with age. Infants and toddlers were mainly injured by scalds and contact burns. Conversely, almost three quarters of injuries over the age of 9 were caused by flame. The majority of scald injuries was a result of pulling down hot liquids. The typical distribution of this accident scenario involved mainly the face, trunk and arms. More than half of all flame injuries occurred due to fire accelerants. 55% of children were passively involved while other children throwing flammable substances into a fire. Most of these injuries involved the face and arms. This study shows that burn etiology is age dependent. Additionally, our results demonstrate the diversity of burn accidents and their resulting injuries. These findings may help better specify target groups and subjects for prevention. Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.

The treatment of sulphur mustard burns with laser debridement.

PubMed

Evison, D; Brown, R F R; Rice, P

2006-01-01

The chemical warfare agent, sulphur mustard (SM), is a potent blistering agent in man. Skin exposure can produce partial-thickness burns which take up to three months to heal. The aim of this study was to investigate the use of early laser ablation as a means of accelerating this exceptionally slow rate of healing. Four circular partial-thickness SM burns were induced on the dorsum of nine large white pigs (under general anaesthesia). At 72 h post-exposure, three burns per animal were ablated with a single pass of an UltraPulse 5000C CO(2) laser, at a fluence of 5-6 J cm(-2). All the burns were dressed with silver sulphadiazine and a semi-occlusive dressing. At one, two and three weeks post-surgery three animals were culled and all lesions excised for histological analysis. Burn depth was confirmed and measurements of the radii of regenerative epithelium were performed allowing the area of the zone of re-epithelialisation in each lesion to be calculated. Laser-treated lesions showed a significant increase (350%) in healing rates compared to controls (p<0.005). At two weeks, the laser-treated sites were 95% healed in comparison with control sites (28% healed). These data suggest that laser ablation may be effective in the treatment of partial-thickness SM-induced skin injury.

A preliminary study of the effect of equivalence ratio on a low emissions gas turbine combustor using KIVA-2

NASA Astrophysics Data System (ADS)

Yang, S. L.; Chen, R.; Cline, M. C.

The staged turbine combustor (STC) concept has drawn more and more attention since the late 70's because of its potential in reducing pollutant emissions where a high power output is required. A numerical study is performed to investigate the chemically reactive flow with sprays inside a STC combustor using a modified version of the KIVA-II code. This STC combustor consists of a fuel nozzle (FN), a rich-burn (RB) zone, a converging connecting section, a quick-quench (QQ) zone, a diverging connecting section, and a lean-combustion (LC) zone. An advanced airblast fuel nozzle, which has two fuel injection passages and four air flow passages for providing swirl, is used in this study. The effect of the equivalence ratio phi on the performance of the STC combustor is reported in this paper for phi range of 1.2 to 2.0. Preliminary results reveal some major features of the flow and temperature fields inside the STC combustor. Distributions of velocity, temperature, and some critical species information inside the FN/RB zone illustrate the effect of phi on the flame temperature and the NO(x) formation in rich burning. The co- and counter-rotating bulk flow, and the sandwiched-ring-shape temperature field in the QQ/LC zone, typical of the confined inclined jet-in-cross flow, are clearly shown from the computation. The predicted mass-weighted standard deviation and the pattern factor of temperature show that the mixing performance of the STC combustor is very good. The temperature of the fluid leaving the LC zone is very uniform. As expected. lower value of the emission index of NO can be achieved with larger value of phi. Prediction of the NO(x) emission shows that there is no excessive thermal NO(x) produced in the QQ/LC zone for all the cases studied.

Antibacterial properties of tualang honey and its effect in burn wound management: a comparative study

PubMed Central

2010-01-01

Background The use of honey as a natural product of Apis spp. for burn treatment has been widely applied for centuries. Tualang honey has been reported to have antibacterial properties against various microorganisms, including those from burn-related diagnoses, and is cheaper and easier to be absorbed by Aquacel dressing. The aim of this study is to evaluate the potential antibacterial properties of tualang honey dressing and to determine its effectiveness as a partial thickness burn wound dressing. Methods In order to quantitate the bioburden of the swabs, pour plates were performed to obtain the colony count (CFU/ml). Swabs obtained from burn wounds were streaked on blood agar and MacConkey agar for bacterial isolation and identification. Later, antibacterial activity of Aquacel-tualang honey, Aquacel-Manuka honey, Aquacel-Ag and Aquacel- plain dressings against bacteria isolated from patients were tested (in-vitro) to see the effectiveness of those dressings by zone of inhibition assays. Results Seven organisms were isolated. Four types of Gram-negative bacteria, namely Enterobacter cloacae, Klebsiella pneumoniae, Pseudomonas spp. and Acinetobacter spp., and three Gram-positive bacteria, namely Staphylococcus aureus, coagulase-negative Staphylococcus aureus (CONS) and Streptococcus spp., were isolated. Total bacterial count decreased on day 6 and onwards. In the in-vitro antibacterial study, Aquacel-Ag and Aquacel-Manuka honey dressings gave better zone of inhibition for Gram positive bacteria compared to Aquacel-Tualang honey dressing. However, comparable results were obtained against Gram negative bacteria tested with Aquacel-Manuka honey and Aquacel-Tualang honey dressing. Conclusions Tualang honey has a bactericidal as well as bacteriostatic effect. It is useful as a dressing, as it is easier to apply and is less sticky compared to Manuka honey. However, for Gram positive bacteria, tualang honey is not as effective as usual care products such as silver-based dressing or medical grade honey dressing. PMID:20576085

Antibacterial properties of tualang honey and its effect in burn wound management: a comparative study.

PubMed

Nasir, Nur-Azida Mohd; Halim, Ahmad Sukari; Singh, Kirnpal-Kaur Banga; Dorai, Ananda Aravazhi; Haneef, Mehru-Nisha Muhammad

2010-06-24

The use of honey as a natural product of Apis spp. for burn treatment has been widely applied for centuries. Tualang honey has been reported to have antibacterial properties against various microorganisms, including those from burn-related diagnoses, and is cheaper and easier to be absorbed by Aquacel dressing. The aim of this study is to evaluate the potential antibacterial properties of tualang honey dressing and to determine its effectiveness as a partial thickness burn wound dressing. In order to quantitate the bioburden of the swabs, pour plates were performed to obtain the colony count (CFU/ml). Swabs obtained from burn wounds were streaked on blood agar and MacConkey agar for bacterial isolation and identification. Later, antibacterial activity of Aquacel-tualang honey, Aquacel-Manuka honey, Aquacel-Ag and Aquacel- plain dressings against bacteria isolated from patients were tested (in-vitro) to see the effectiveness of those dressings by zone of inhibition assays. Seven organisms were isolated. Four types of Gram-negative bacteria, namely Enterobacter cloacae, Klebsiella pneumoniae, Pseudomonas spp. and Acinetobacter spp., and three Gram-positive bacteria, namely Staphylococcus aureus, coagulase-negative Staphylococcus aureus (CONS) and Streptococcus spp., were isolated. Total bacterial count decreased on day 6 and onwards. In the in-vitro antibacterial study, Aquacel-Ag and Aquacel-Manuka honey dressings gave better zone of inhibition for Gram positive bacteria compared to Aquacel-Tualang honey dressing. However, comparable results were obtained against Gram negative bacteria tested with Aquacel-Manuka honey and Aquacel-Tualang honey dressing. Tualang honey has a bactericidal as well as bacteriostatic effect. It is useful as a dressing, as it is easier to apply and is less sticky compared to Manuka honey. However, for Gram positive bacteria, tualang honey is not as effective as usual care products such as silver-based dressing or medical grade honey dressing.

Nitrogen dynamics in northern peatland ecosystems

EPA Science Inventory

Nitrogen pollution has become a global issue over the last century due to increased fertilizer use and burning of fossil fuels. Excess N has been responsible for algal blooms, hypoxic zones, climate change, and human health issues. Extent of peatlands in the Great Lakes basin is ...

Measurement of transient gas flow parameters by diode laser absorption spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bolshov, M A; Kuritsyn, Yu A; Liger, V V

2015-04-30

An absorption spectrometer based on diode lasers is developed for measuring two-dimension maps of temperature and water vapour concentration distributions in the combustion zones of two mixing supersonic flows of fuel and oxidiser in the single run regime. The method of measuring parameters of hot combustion zones is based on detection of transient spectra of water vapour absorption. The design of the spectrometer considerably reduces the influence of water vapour absorption along the path of a sensing laser beam outside the burning chamber. The optical scheme is developed, capable of matching measurement results in different runs of mixture burning. Amore » new algorithm is suggested for obtaining information about the mixture temperature by constructing the correlation functions of the experimental spectrum with those simulated from databases. A two-dimensional map of temperature distribution in a test chamber is obtained for the first time under the conditions of plasma-induced combusion of the ethylene – air mixture. (laser applications and other topics in quantum electronics)« less

Comparison of Mixing Calculations for Reacting and Non-Reacting Flows in a Cylindrical Duct

NASA Technical Reports Server (NTRS)

Oechsle, V. L.; Mongia, H. C.; Holdeman, J. D.

1994-01-01

A production 3-D elliptic flow code has been used to calculate non-reacting and reacting flow fields in an experimental mixing section relevant to a rich burn/quick mix/lean burn (RQL) combustion system. A number of test cases have been run to assess the effects of the variation in the number of orifices, mass flow ratio, and rich-zone equivalence ratio on the flow field and mixing rates. The calculated normalized temperature profiles for the non-reacting flow field agree qualitatively well with the normalized conserved variable isopleths for the reacting flow field indicating that non-reacting mixing experiments are appropriate for screening and ranking potential rapid mixing concepts. For a given set of jet momentum-flux ratio, mass flow ratio, and density ratio (J, MR, and DR), the reacting flow calculations show a reduced level of mixing compared to the non-reacting cases. In addition, the rich-zone equivalence ratio has noticeable effect on the mixing flow characteristics for reacting flows.

Impact of Wildfire on Microbial Biomass in Critical Zone Observatory

NASA Astrophysics Data System (ADS)

Murphy, M. A.; Fairbanks, D.; Chorover, J.; Gallery, R. E.; Rich, V. I.

2014-12-01

The recovery of the critical zone following disturbances such as wildfire is not fully understood. Wildfires have increased in size and intensity in western US forests in recent years and these fires influence soil microbial communities, both in composition and overall biomass. Studies have typically shown a 50% post-fire decline in overall microbial biomass (µg per g soil) that can persist for years. There is however, some variability in the severity of biomass decline, and its relationship with burn severity and landscape position have not yet been studied. Since microbial biomass has a cascade of impacts in soil systems, from helping control the rate and diversity the biogeochemical processes occurring, to promoting soil fertility, to impacting the nature and structure of soil carbon (C), fire's lasting impact on it is one mechanistic determinant of the overall post-fire recovery of impacted ecosystems. Additionally, microbial biomass measurements hold potential for testing and incorporation into land surface models (NoahMP, CLM, etc.) in order to improve estimates of long-term effects of climate change and disturbances such as fire on the C cycle. In order to refine our understanding of the impact of fire on microbial biomass and then relate that to biogeochemical processes and ecosystem recovery, we used chloroform fumigation extraction to quantify total microbial biomass C (Cmic ). One year after the June 2013 Thompson Ridge fire in the Jemez River Basin Critical Zone Observatory, we are measuring the Cmic of 22 sites across a gradient of burn severities and 4 control unburned sites, from six depth intervals at each site (0-2, 2-5, 5-10, 10-20, 20-30, and 30-40 cm). We hypothesize that the decrease in microbial biomass in burned sites relative to control sites will correlate with changes in soil biogeochemistry related to burn severity; and that the extent of the impact on biomass will be inversely related to depth in the soil column. Additionally, as the project progresses, we will relate microbial biomass to microbial functional assays as proxy for biogeochemical activity, and test variation by landscape position and aspect.

Sun tanning-related burns--a 3-year experience.

PubMed

Piccolo-Lobo, M S; Piccolo, N S; Piccolo-Daher, M T; Cardoso, V M

1992-04-01

A retrospective study has analyzed 562 sun-related burns out of 19,643 patients treated at our institution from 1 March 1988 to 28 February 1991. These patients were analysed according to sex, age, burn area, mode and length of treatment and outcome. Females, mainly adults, represented 60.8 per cent of all patients presenting burned due to sun bathing. There is a marked seasonal incidence, proportionally constant throughout these 3 years. The main causes of injury were sun only (36.7 per cent), sun plus fig leaf 'tea' tanning lotion (17.7 per cent) and lemon juice (17.7 per cent). Healing to normal skin appearance was achieved in 99.1 per cent, 0.7 per cent healed with scarring and one patient died due to massive sepsis. The effect of sunlight on skin and the process of 'sunburn' when using homemade plant-derived tanning lotions containing substances which can induce a photodermatitis reaction is also discussed.

[Ischemic cholangiopathy induced by extended burns].

PubMed

Cohen, Laurence; Angot, Emilie; Goria, Odile; Koning, Edith; François, Arnaud; Sabourin, Jean-Christophe

2013-04-01

Ischemic cholangiopathy is a recently described entity occurring mainly after hepatic grafts. Very few cases after intensive care unit (ICU) for extended burn injury were reported. We report the case of a 73-year-old woman consulting in an hepatology unit, for a jaundice appearing during a hospitalisation in an intensive care unit and increasing from her leaving from ICU, where she was treated for an extended burn injury. She had no pre-existing biological features of biliary disease. Biological tests were normal. Magnetic resonance imaging acquisitions of biliary tracts pointed out severe stenosing lesions of diffuse cholangiopathy concerning intrahepatic biliary tract, mainly peri-hilar. Biopsie from the liver confirmed the diagnosis, showing a biliary cirrhosis with bile infarcts. This case is the fourth case of ischemic cholangiopathy after extended burn injury, concerning a patient without a prior history of hepatic or biliary illness and appearing after hospitalisation in intensive care unit. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Propolis: A Wonder Bees Product and Its Pharmacological Potentials

PubMed Central

Wagh, Vijay D.

2013-01-01

Propolis is a natural resinous mixture produced by honey bees from substances collected from parts of plants, buds, and exudates. Due to its waxy nature and mechanical properties, bees use propolis in the construction and repair of their hives for sealing openings and cracks and smoothing out the internal walls and as a protective barrier against external invaders like snakes, lizards, and so forth, or against weathering threats like wind and rain. Bees gather propolis from different plants, in the temperate climate zone mainly from poplar. Current antimicrobial applications of propolis include formulations for cold syndrome (upper respiratory tract infections, common cold, and flu-like infections), wound healing, treatment of burns, acne, herpes simplex and genitalis, and neurodermatitis. Worldwide propolis has a tremendous popularity, but in India the studies over propolis have just started, not extensively reported except few regions of India like Maharashtra, West Bengal, Tamil Nadu, Gujrat, and Madhya Pradesh. PMID:24382957

Short Term Soil Respiration Response to Fire in a Semi-arid Ecosystem

NASA Astrophysics Data System (ADS)

Rozin, A. G.

2015-12-01

In the Intermountain West (USA), fire is an important driver of carbon cycling in the environment. Increasing frequency and severity of fires, either through management actions or wildfires, is expected with changing climates in the Western United States. When burning is used as a management tool, it may be beneficial and control the growth of nuisance vegetation, promote the regeneration of grasses and forage species, and reduce hazardous fuel loads to minimize the risk of future wildfires. However, high intensity wildfires often have a negative effect, resulting in a loss of carbon storage and a shift of vegetation communities. This delays recovery of the ecosystem for years or decades and alters the historic fire regime. A 2000 acre prescribed burn in the Reynolds Creek Critical Zone Observatory provided the opportunity to quantify pre and post-burn soil carbon stores and soil carbon losses by heterotrophic respiration. Pre and post-burn soil samples were collected for physical and biogeochemical characterization to quantify substrate availability and possible limitations for heterotrophic respiration. CO2 fluxes were continuously monitored in situ before and immediately after the fire to understand the short-term response of soil respiration to varying burn severities.

Properties of convective oxygen and silicon burning shells in supernova progenitors

NASA Astrophysics Data System (ADS)

Collins, Christine; Müller, Bernhard; Heger, Alexander

2018-01-01

Recent 3D simulations have suggested that convective seed perturbations from shell burning can play an important role in triggering neutrino-driven supernova explosions. Since isolated simulations cannot determine whether this perturbation-aided mechanism is of general relevance across the progenitor mass range, we here investigate the pertinent properties of convective oxygen and silicon burning shells in a broad range of pre-supernova stellar evolution models. We find that conditions for perturbation-aided explosions are most favourable in the extended oxygen shells of progenitors between about 16 and 26 solar masses, which exhibit large-scale convective overturn with high convective Mach numbers. Although the highest convective Mach numbers of up to 0.3 are reached in the oxygen shells of low-mass progenitors, convection is typically dominated by small-scale modes in these shells, which implies a more modest role of initial perturbations in the explosion mechanism. Convective silicon burning rarely provides the high Mach numbers and large-scale perturbations required for perturbation-aided explosions. We also find that about 40 per cent of progenitors between 16 and 26 solar masses exhibit simultaneous oxygen and neon burning in the same convection zone as a result of a shell merger shortly before collapse.

Forest Fires Darken Snow for Years following Disturbance: Magnitude, Duration, and Composition of Light Absorbing Impurities in Seasonal Snow across a Chronosequence of Burned Forests in the Colorado River Headwaters

NASA Astrophysics Data System (ADS)

Gleason, K. E.; Arienzo, M. M.; Chellman, N.; McConnell, J.

2017-12-01

Charred forests shed black carbon and burned debris, which accumulates and concentrates on winter snowpack, reducing snow surface albedo, and subsequently increasing snowmelt rates, and advancing the date of snow disappearance. Forest fires have occurred across vast areas of the seasonal snow zone in recent decades, however we do not understand the long-term implications of burned forests in montane headwaters to snow hydrology and downstream water resources. Across a chronosequence of nine burned forests in the Colorado River Headwaters, we sampled snow throughout the complete snowpack profile to conserve the composition, properties, and vertical stratigraphy of impurities in the snowpack during maximum snow accumulation. Using state-of-the-art geochemical analyses, we determined the magnitude, composition, and particle size distribution of black carbon, dust, and other impurities in the snowpack relative to years-since fire. Forest fires continue to darken snow for many years following fire, however the magnitude, composition, and particle size distribution of impurities change through time, altering the post-fire radiative forcing on snow as a burned forest ages.

Generalized Pseudo-Reaction Zone Model for Non-Ideal Explosives

NASA Astrophysics Data System (ADS)

Wescott, Bradley

2007-06-01

The pseudo-reaction zone model was proposed to improve engineering scale simulations when using Detonation Shock Dynamics with high explosives that have a slow reaction component. In this work an extension of the pseudo-reaction zone model is developed for non-ideal explosives that propagate well below their steady-planar Chapman-Jouguet velocity. A programmed burn method utilizing Detonation Shock Dynamics and a detonation velocity dependent pseudo-reaction rate has been developed for non-ideal explosives and applied to the explosive mixture of ammonium nitrate and fuel oil (ANFO). The pseudo-reaction rate is calibrated to the experimentally obtained normal detonation velocity---shock curvature relation. The generalized pseudo-reaction zone model proposed here predicts the cylinder expansion to within 1% by accounting for the slow reaction in ANFO.

Removal of oxides of nitrogen from gases in multi-stage coal combustion

DOEpatents

Mollot, D.J.; Bonk, D.L.; Dowdy, T.E.

1998-01-13

Polluting NO{sub x} gas values are removed from off-gas of a multi-stage coal combustion process which includes an initial carbonizing reaction, firing of char from this reaction in a fluidized bed reactor, and burning of gases from the carbonizing and fluidized bed reactions in a topping combustor having a first, fuel-rich zone and a second, fuel-lean zone. The improvement by means of which NO{sub x} gases are removed is directed to introducing NO{sub x}-free oxidizing gas such as compressor air into the second, fuel-lean zone and completing combustion with this source of oxidizing gas. Excess air fed to the fluidized bed reactor is also controlled to obtain desired stoichiometry in the first, fuel-rich zone of the topping combustor. 2 figs.

Removal of oxides of nitrogen from gases in multi-stage coal combustion

DOEpatents

Mollot, Darren J.; Bonk, Donald L.; Dowdy, Thomas E.

1998-01-01

Polluting NO.sub.x gas values are removed from off-gas of a multi-stage coal combustion process which includes an initial carbonizing reaction, firing of char from this reaction in a fluidized bed reactor, and burning of gases from the carbonizing and fluidized bed reactions in a topping combustor having a first, fuel-rich zone and a second, fuel-lean zone. The improvement by means of which NO.sub.x gases are removed is directed to introducing NO.sub.x -free oxidizing gas such as compressor air into the second, fuel-lean zone and completing combustion with this source of oxidizing gas. Excess air fed to the fluidized bed reactor is also controlled to obtain desired stoichiometry in the first, fuel-rich zone of the topping combustor.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Menikoff, Ralph

The Zel’dovich-von Neumann-Doering (ZND) profile of a detonation wave is derived. Two basic assumptions are required: i. An equation of state (EOS) for a partly burned explosive; P(V, e, λ). ii. A burn rate for the reaction progress variable; d/dt λ = R(V, e, λ). For a steady planar detonation wave the reactive flow PDEs can be reduced to ODEs. The detonation wave profile can be determined from an ODE plus algebraic equations for points on the partly burned detonation loci with a specified wave speed. Furthermore, for the CJ detonation speed the end of the reaction zone is sonic.more » A solution to the reactive flow equations can be constructed with a rarefaction wave following the detonation wave profile. This corresponds to an underdriven detonation wave, and the rarefaction is know as a Taylor wave.« less

Posters also presented at the Symposium

NASA Astrophysics Data System (ADS)

Eldridge, J. J.; Bray, J. C.; McClelland, L. A. S.; Xiao, L.

2017-11-01

I am reporting on our team's progress in investigating fundamental properties of convective shells in the deep stellar interior during advanced stages of stellar evolution. We have performed a series of 3D hydrodynamic simulations of convection in conditions similar to those in the O-shell burning phase of massive stars. We focus on characterizing the convective boundary and the mixing of material across this boundary. Results from 7683 and 15363 grids are encouragingly similar (typically within 20%). Several global quantities, including the rate of mass entrainment at the convective boundary and the driving luminosity, are related by scaling laws. We investigate the effect of several of our assumptions, including the treatment of the nuclear burning driving the convection or that of neutrino cooling. The burning of the entrained material from above the convection zone could have important implications for pre-supernova nucleosynthesis.

Prescribed fire experiences on crop residue removal for biomass exploitations. Application to the maritime pine forests in the Mediterranean Basin.

PubMed

Molina, Juan Ramón; García, Juan Pedro; Fernández, Juan José; Rodríguez Y Silva, Francisco

2018-01-15

Socioeconomic changes, climate change, rural migration and fire exclusion have led to a high woody biomass accumulation increasing potential wildfire severity. Mechanical thinning and prescribed burning practices are commonly used to prevent large fires. The purpose of this study was to assess burning treatment effectiveness following mechanical thinning from biomass harvesting. Prescribed burning to reduce residue removal could help mitigate fire behavior, mainly in strategic management or critical focal points. Field samplings were conducted before and immediately after burnings on different environmental scenarios where fuel load was classified by categories. Prescribed fires reduced available fuel in all fuel categories, mainly in surface litter layer. Total fuel load reduction ranged from 59.07% to 86.18%. In this sense, fuel reduction effects were more pronounced when burns were conducted fewer than 10% on surface litter moisture. The difference in fuel consumption among scenarios was higher for most all woody fuel components and decomposition litter layer than for surface litter layer. Managers can use this information to design technical prescription to achieve the targets while decomposed litter retention maintaining the soil properties and biodiversity. Understanding the most effective "burn window" should help better plan prescribed burning, both in term of fire behavior and fuel consumption, without altering ecosystem properties. Copyright © 2017 Elsevier B.V. All rights reserved.

Face Allotransplantation and Burns: a Review

PubMed Central

A, Arno; JP, Barret; RA, Harrison; MG, Jeschke

2012-01-01

Burns may represent one of the main indications for face allotransplantation. Severely disfigured faces featuring a devastating appearance and great functional impairments are not only seen as burn sequelae, but also occur as a result of other traumatic injuries, oncological surgical resections, benign tumors (e.g., neurofibromatosis), and major congenital malformations. To date, sixteen human face composite tissue allotransplantations have been performed with success. Despite the initial scepticism about its applicability, due mainly to ethical and technical reasons, the previous worldwide cases and their associated positive outcomes –including acceptable immunosuppressive regimens, excellent aesthetic and functional results, and good psychological acceptance by the recipient- , enable the conclusion that face composite tissue allotransplantation has become another therapeutic strategy in the reconstructive surgical armamentarium, which bears special consideration when dealing with severely disfigured burned patients. The aim of this review is to describe the basics of face composite tissue allotransplantation and give an overview of some of the cases performed until now, with special attention paid to debating the pros and cons of its applicability in burn patients. PMID:22274632

Stably operating pulse combustor and method

DOEpatents

Zinn, B.T.; Reiner, D.

1990-05-29

A pulse combustor apparatus is described which is adapted to burn either a liquid fuel or a pulverized solid fuel within a preselected volume of the combustion chamber. The combustion process is substantially restricted to an optimum combustion zone in order to attain effective pulse combustion operation. 4 figs.

Postdischarge Cause-of-Death Analysis of Combat-Related Burn Patients

PubMed Central

Escolas, Sandra M.; Orman, Jean A.; Chung, Kevin K.; Renz, Evan M.

2017-01-01

Combat operations in Iraq and Afghanistan have resulted in up to 8.8% of combat-related casualties suffering burns. From World War I through Desert Storm, burns have been associated with approximately 4% of the combat-related deaths. Experiencing a blast injury and exposure to killing and death while deployed has been shown to increase suicide risk. Although several studies of military populations have investigated risk factors for death among burn patients during the acute phase, no studies have reported mortality rates, cause-of-death, or the prevalence of suicide after hospital discharge. This study examined the case fatality rate, causes of death, and the prevalence of suicide among 830 combat burn patients discharged from the sole burn center in the U.S. Department of Defense, between March 7, 2003 and March 6, 2013. Cause-of-death was determined through the Armed Forces Medical Examiner’s Office and the Office of the Secretary of Defense’s National Death Index. A total of 11 deaths occurred among the 830 burn survivors, for an overall case fatality rate of 1.3%. Of the 11 who died, five deaths were related to accidental poisoning by exposure to drugs; three were related to operations of war (two after returning to the war zone), and the remaining three died from other accidental causes (one explosion and two vehicle crashes). There was no indication of suicide or suspicion of suicide as a cause-of-death for the former patients included in this study, suggesting that combat burn injury did not appear to increase the risk of death by suicide in our study population. Further research is needed to understand the factors that contribute to the apparent resilience of combat burn survivors. PMID:26629656

Lightning Forcing in Global Fire Models: The Importance of Temporal Resolution

NASA Astrophysics Data System (ADS)

Felsberg, A.; Kloster, S.; Wilkenskjeld, S.; Krause, A.; Lasslop, G.

2018-01-01

In global fire models, lightning is typically prescribed from observational data with monthly mean temporal resolution while meteorological forcings, such as precipitation or temperature, are prescribed in a daily resolution. In this study, we investigate the importance of the temporal resolution of the lightning forcing for the simulation of burned area by varying from daily to monthly and annual mean forcing. For this, we utilize the vegetation fire model JSBACH-SPITFIRE to simulate burned area, forced with meteorological and lightning data derived from the general circulation model ECHAM6. On a global scale, differences in burned area caused by lightning forcing applied in coarser temporal resolution stay below 0.55% compared to the use of daily mean forcing. Regionally, however, differences reach up to 100%, depending on the region and season. Monthly averaged lightning forcing as well as the monthly lightning climatology cause differences through an interaction between lightning ignitions and fire prone weather conditions, accounted for by the fire danger index. This interaction leads to decreased burned area in the boreal zone and increased burned area in the Tropics and Subtropics under the coarser temporal resolution. The exclusion of interannual variability, when forced with the lightning climatology, has only a minor impact on the simulated burned area. Annually averaged lightning forcing causes differences as a direct result of the eliminated seasonal characteristics of lightning. Burned area is decreased in summer and increased in winter where fuel is available. Regions with little seasonality, such as the Tropics and Subtropics, experience an increase in burned area.

ASTEROSEISMOLOGY OF THE NEARBY SN II PROGENITOR RIGEL. II. {epsilon}-MECHANISM TRIGGERING GRAVITY-MODE PULSATIONS?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moravveji, Ehsan; Moya, Andres; Guinan, Edward F., E-mail: moravveji@iasbs.ac.ir

2012-04-10

The cores of luminous B- and A-type (BA) supergiant stars are the seeds of later core-collapse supernovae. Thus, constraining the near-core conditions in this class of stars can place tighter constraints on the size, mass, and chemical composition of supernova remnants. Asteroseismology of these massive stars is one possible approach into such investigations. Recently, Moravveji et al. in 2012 (hereafter Paper I) extracted 19 significant frequencies from a 6-year radial velocity monitoring of Rigel ({beta} Ori, B8 Ia). The periods they determined broadly range from 1.22 to 74.74 days. Based on our differentially rotating stellar structure and evolution model, Rigel,more » at its current evolutionary state, is undergoing core He burning and shell H burning. Linear fully non-adiabatic non-radial stability analyses result in the excitation of a dense spectrum of non-radial gravity-dominated mixed modes. The fundamental radial mode (l = 0) and its overtones are all stable. When the hydrogen-burning shell is located even partially in the radiative zone, a favorable condition for destabilization of g-modes through the so-called {epsilon}-mechanism becomes viable. Only those g-modes that have high relative amplitudes in the hydrogen-burning (radiative) zone can survive the strong radiative damping. From the entire observed range of variability periods of Rigel (found in Paper I), and based on our model, only those modes with periods ranging between 21 and 127 days can be theoretically explained by the {epsilon}-mechanism. The origin of the short-period variations (found in Paper I) still remains unexplained. Because Rigel is similar to other massive BA supergiants, we believe that the {epsilon}-mechanism may be able to explain the long-period variations in {alpha} Cygni class of pulsating stars.« less

NO 2 oxidation reactivity and burning mode of diesel particulates

DOE PAGES

Strzelec, Andrea; Vander Wal, Randy L.; Thompson, Thomas N.; ...

2016-03-24

The NO 2 oxidation kinetics and burning mode for diesel particulate from light-duty and medium-duty engines fueled with either ultra low sulfur diesel or soy methyl ester biodiesel blends have been investigated and are shown to be significantly different from oxidation by O 2. Oxidation kinetics were measured using a flow-through packed bed microreactor for temperature programmed reactions and isothermal differential pulsed oxidation reactions. The burning mode was evaluated using the same reactor system for flowing BET specific surface area measurements and HR-TEM with fringe analysis to evaluate the nanostructure of the nascent and partially oxidized particulates. The low activationmore » energy measured, specific surface area progression with extent of oxidation, HR-TEM images and difference plots of fringe length and tortuosity paint a consistent picture of higher reactivity for NO 2, which reacts indiscriminately immediately upon contact with the surface, leading to the Zone I or shrinking core type oxidation. In comparison, O 2 oxidation is shown to have relatively lower reactivity, preferentially attacking highly curved lamella, which are more reactive due to bond strain, and short lamella, which have a higher proportion of more reactive edge sites. Furthermore, this preferential oxidation leads to Zone II type oxidation, where solid phase diffusion of oxygen via pores contributes significantly to slowing the overall oxidation rate, by comparison.« less

Epidemiological data and costs of burn injuries in workers in Switzerland: an argument for immediate treatment in burn centres.

PubMed

de Roche, R; Lüscher, N J; Debrunner, H U; Fischer, R

1994-02-01

A complete statistical evaluation of epidemiological data and costs of burn injuries in 1984 with a follow-up for 5 years is presented, considering a collective of 1.77 million workers in Switzerland. The majority of burns are minor injuries; only about 5 per cent of the burn victims are admitted to a hospital, 0.2 per cent died. Burn injuries at work are rare, mainly owing to strict safety measures. Only one-fifth of the costs caused by burns are due to medical treatment. All other expenses result from continuation of payments of salaries and annuities. The treatment of the few severely burned patients in burn units produces effective costs which are higher than the tariff paid by the insurance. Even so, the predominant portion of the enormous costs is taken up by wages while off work and annuities. As our conclusion we stress the importance of primary care for all severe burns including all burns of the hands in a specialized centre. Any economic effort for primary burn treatment, however high it may be, is justified if the duration of rehabilitation and invalidity can be reduced.

The solar Lithium problem: is the explanation due solely to mixing or also to the e-capture decay rate of 7Be?

NASA Astrophysics Data System (ADS)

Vescovi, Diego; Busso, Maurizio; Palmerini, Sara; Trippella, Oscar

2018-01-01

The nucleosynthesis of 7Li is one of the most crucial problems in nuclear as- trophysics, as its observations in several sites are hard to be explained. Concerning the Sun, the most common interpretations of the low Li abundance invoke either burning in early stages or non-convective mixing below the envelope. Here we apply a diffusive mechanism of mixing, together with a recent estimate of the rate for e-captures on 7Be, to establish whether the solar Li destruction should be attributed to purely pre-Main Se- quence (MS) nuclear processes or if the coupling of mixing and nucleosynthesis on the MS can account for it. Our preliminary results indicate that, whether Li survives the pre- MS phase, the changes of the 7Be e--capture rate do not affect its production/destruction. The low Li abundance should then depend only on diffusion processes from the bottom of the convective envelope to the lowerlying tachocline zone. We suggest that, if diffusive processes occurred over the age of the Sun, they required diffusive mass transfers of a few 10-13 M⊙/yr to explain the Li drop. This is a high estimate: future works will tell us if it is realistic or not. In this second case, pre-MS burning would remain the only alternative.

Ethnicity and etiology in burn trauma.

PubMed

Papp, Anthony; Haythornthwaite, Jordan

2014-01-01

The purpose of this study was to retrieve data from the British Columbia Professional Firefighters Burn Unit registry, with a focus on ethnicity and how it is involved in burn trauma. It is hypothesized that mechanism, severity, and other patient characteristics are significantly different among different ethnic groups. Furthermore, it is believed that these data can be used to augment burn prevention strategies. Data for burn patients admitted from 1979 to 2009 were reviewed from the burn registry. The main focus was with differences seen among the four main ethnicities throughout the analysis, Caucasian, Aboriginal, Asian, and Indoasian, reflecting the population distribution of the region. Age and sex were also considered when looking at burn mechanism, severity, contributing and copresenting factors. Caucasians were the largest group (79.1%) and included the largest male:female ratio (3.3:1), with high numbers of flame injury (53.9%). Caucasians presented with the highest mortality (6.6% compared with 4.1% for all other ethnicities; P < .006). Asian patients (8.1%) showed significantly higher occurrences of urban (64%) and workplace (28.9%) injuries with a larger proportion of scald injury (38.9%). Indoasian patients included larger numbers of women (36.4%) and household scald injuries (33.9%) whereas Aboriginals suffered the most flame injuries (60.1%) in rural areas with more frequent contributing factors such as alcohol. The study found multiple significant differences in the burn injury population when segmented by ethnicity. Though the exact reasons for these differences are difficult to say with certainty, it allows a unique opportunity to focus communication and prevention efforts to specific communities.

Resistance of the boreal forest to high burn rates.

PubMed

Héon, Jessie; Arseneault, Dominique; Parisien, Marc-André

2014-09-23

Boreal ecosystems and their large carbon stocks are strongly shaped by extensive wildfires. Coupling climate projections with records of area burned during the last 3 decades across the North American boreal zone suggests that area burned will increase by 30-500% by the end of the 21st century, with a cascading effect on ecosystem dynamics and on the boreal carbon balance. Fire size and the frequency of large-fire years are both expected to increase. However, how fire size and time since previous fire will influence future burn rates is poorly understood, mostly because of incomplete records of past fire overlaps. Here, we reconstruct the length of overlapping fires along a 190-km-long transect during the last 200 y in one of the most fire-prone boreal regions of North America to document how fire size and time since previous fire will influence future fire recurrence. We provide direct field evidence that extreme burn rates can be sustained by a few occasional droughts triggering immense fires. However, we also show that the most fire-prone areas of the North American boreal forest are resistant to high burn rates because of overabundant young forest stands, thereby creating a fuel-mediated negative feedback on fire activity. These findings will help refine projections of fire effect on boreal ecosystems and their large carbon stocks.

Resistance of the boreal forest to high burn rates

PubMed Central

Héon, Jessie; Arseneault, Dominique; Parisien, Marc-André

2014-01-01

Boreal ecosystems and their large carbon stocks are strongly shaped by extensive wildfires. Coupling climate projections with records of area burned during the last 3 decades across the North American boreal zone suggests that area burned will increase by 30–500% by the end of the 21st century, with a cascading effect on ecosystem dynamics and on the boreal carbon balance. Fire size and the frequency of large-fire years are both expected to increase. However, how fire size and time since previous fire will influence future burn rates is poorly understood, mostly because of incomplete records of past fire overlaps. Here, we reconstruct the length of overlapping fires along a 190-km-long transect during the last 200 y in one of the most fire-prone boreal regions of North America to document how fire size and time since previous fire will influence future fire recurrence. We provide direct field evidence that extreme burn rates can be sustained by a few occasional droughts triggering immense fires. However, we also show that the most fire-prone areas of the North American boreal forest are resistant to high burn rates because of overabundant young forest stands, thereby creating a fuel-mediated negative feedback on fire activity. These findings will help refine projections of fire effect on boreal ecosystems and their large carbon stocks. PMID:25201981

Maternal burn-out: an exploratory study.

PubMed

Séjourné, N; Sanchez-Rodriguez, R; Leboullenger, A; Callahan, S

2018-02-21

Maternal burn-out is a psychological, emotional and physiological condition resulting from the accumulation of various stressors characterised by a moderate but also a chronic and repetitive dimension. Little research has focused on this syndrome. The current study aims to assess maternal burn-out rate and to identify factors associated with this state of exhaustion. 263 French mothers aged between 20 and 49 years answered five scales quantifying maternal burn-out, perceived social support, parental stress, depression and anxiety symptoms and history of postnatal depression. About 20% of mothers were affected by maternal burn-out. The main factors related to maternal burn-out were having a child perceived as difficult, history of postnatal depression, anxiety, satisfaction of a balance between professional and personal life and parental stress. This research shows the need for further work on maternal burn-out to better understand and prevent this syndrome.

Childhood burns in south eastern Nigeria.

PubMed

Archibong, A E; Antia, U E; Udosen, J

1997-06-01

In a ten year retrospective study of burns in children in University of Calabar Teaching Hospital (UCTH), Calabar, the main causes were hot water, hot soup or oil (56.6%) involving children mostly in the one to three year age group. The relative safety of the home environment seen in other forms of paediatric trauma is not observed in burns in children. A changing pattern of burns in children has emerged within the region with naked flames/bush fire coming second and affecting 22.7% of the children. Chemical burns hitherto a rare occurrence is now frequent because of the storage of caustic soda and acids in living rooms by soap making parents. Burns affecting the perineum, axilla and buttocks are difficult to keep clean and frequently lead to infections, with associated increased morbidity. Causes of childhood burns are largely preventable requiring active social/medical education and public enlightenment campaigns on the various methods of prevention.

Solid-propellant rocket motor internal ballistic performance variation analysis, phase 2

NASA Technical Reports Server (NTRS)

Sforzini, R. H.; Foster, W. A., Jr.

1976-01-01

The Monte Carlo method was used to investigate thrust imbalance and its first time derivative throughtout the burning time of pairs of solid rocket motors firing in parallel. Results obtained compare favorably with Titan 3 C flight performance data. Statistical correlations of the thrust imbalance at various times with corresponding nominal trace slopes suggest several alternative methods of predicting thrust imbalance. The effect of circular-perforated grain deformation on internal ballistics is discussed, and a modified design analysis computer program which permits such an evaluation is presented. Comparisons with SRM firings indicate that grain deformation may account for a portion of the so-called scale factor on burning rate between large motors and strand burners or small ballistic test motors. Thermoelastic effects on burning rate are also investigated. Burning surface temperature is calculated by coupling the solid phase energy equation containing a strain rate term with a model of gas phase combustion zone using the Zeldovich-Novozhilov technique. Comparisons of solutions with and without the strain rate term indicate a small but possibly significant effect of the thermoelastic coupling.

Enhancement of burning velocity by dissociated oxygen atoms

NASA Astrophysics Data System (ADS)

Akashi, Haruaki; Yoshinaga, Tomokazu; Sasaki, Koichi

2015-09-01

Green technology, such as preventing global warming, has been developed for years. Researches on plasma assisted combustion is one of the technologies and have been done for investigating more efficient combustion, more efficient use of fossil fuel with plasmas or applying electric fields. In the ignition time delay analyses with the dissociated oxygen atoms which is generated by non-equilibrium plasma had significant effect on the ignition time. In this paper, dissociated oxygen could effect on burning velocity or not has been examined using CHEMKIN. As a result, no effect can be seen with dissociation degree of lower than 10-3. But there is an effect on the enhancement of burning velocity with higher degree of 10-3. At the dissociation degree of 5×10-2, the burning velocity is enhanced at a factor of 1.24. And it is found that the distributions of each species in front of preheat zone are completely different. The combustion process is proceeded several steps in advance, and generation of H2O, CO and CO2 can be seen before combustion in higher dissociation case. This work was supported by KAKENHI (22340170).

β -decay rate of 59Fe in shell burning environment and its influence on the production of 60Fe in a massive star

NASA Astrophysics Data System (ADS)

Li, K. A.; Lam, Y. H.; Qi, C.; Tang, X. D.; Zhang, N. T.

2016-12-01

We deduced the stellar β -decay rate of 59Fe at typical carbon-shell burning temperature by taking the experimental Gamow-Teller transition strengths of the 59Fe excited states. The result is also compared with those derived from large-scale shell model calculations. The new rate is up to a factor of 2.5 lower than the theoretical rate of Fuller, Fowler, and Newman (FFN) and up to a factor of 5 higher than decay rate of Langanke and Martínez-Pinedo (LMP) in the temperature region 0.5 ≤T ≤2 GK. We estimated the impact of the newly determined rate on the synthesis of cosmic γ emitter 60Fe in C-shell burning and explosive C/Ne burning using a one-zone model calculation. Our results show that 59Fe stellar β decay plays an important role in 60Fe nucleosynthesis, even though the uncertainty of the decay rate is rather large due to the error of B (GT) strengths.

Slag processing system for direct coal-fired gas turbines

DOEpatents

Pillsbury, Paul W.

1990-01-01

Direct coal-fired gas turbine systems and methods for their operation are provided by this invention. The gas turbine system includes a primary zone for burning coal in the presence of compressed air to produce hot combustion gases and debris, such as molten slag. The turbine system further includes a secondary combustion zone for the lean combustion of the hot combustion gases. The operation of the system is improved by the addition of a cyclone separator for removing debris from the hot combustion gases. The cyclone separator is disposed between the primary and secondary combustion zones and is in pressurized communication with these zones. In a novel aspect of the invention, the cyclone separator includes an integrally disposed impact separator for at least separating a portion of the molten slag from the hot combustion gases.

Effects of burn location and investigator on burn depth in a porcine model.

PubMed

Singer, Adam J; Toussaint, Jimmy; Chung, Won Taek; Thode, Henry C; McClain, Steve; Raut, Vivek

2016-02-01

In order to be useful, animal models should be reproducible and consistent regardless of sampling bias, investigator creating burn, and burn location. We determined the variability in burn depth based on biopsy location, burn location and investigator in a porcine model of partial thickness burns. 24 partial thickness burns (2.5 cm by 2.5 cm each) were created on the backs of 2 anesthetized pigs by 2 investigators (one experienced, one inexperienced) using a previously validated model. In one of the pigs, the necrotic epidermis covering each burn was removed. Five full thickness 4mm punch biopsies were obtained 1h after injury from the four corners and center of the burns and stained with Hematoxylin and Eosin and Masson's trichrome for determination of burn depth by a board certified dermatopathologist blinded to burn location and investigator. Comparisons of burn depth by biopsy location, burn location and investigator were performed with t-tests and ANOVA as appropriate. The mean (SD) depth of injury to blood vessels (the main determinant of burn progression) in debrided and non-debrided pigs pooled together was 1.8 (0.3)mm, which included 75% of the dermal depth. Non-debrided burns were 0.24 mm deeper than debrided burns (P<0.001). Burn depth increased marginally from cephalic to caudal in non-debrided burns, but showed no statistical differences for these locations, in debrided burns. Additionally, there were also no statistical differences in burn depths from midline to lateral in either of these burn types. Burn depth was similar for both investigators and among biopsy locations. Burn depth was greater for caudal locations in non-debrided burns and overall non-debrided burns were deeper than debrided burns. However, burn depth did not differ based on investigator, biopsy site, and medial-lateral location. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

Global analysis of the persistence of the spectral signal associated with burned areas

NASA Astrophysics Data System (ADS)

Melchiorre, A.; Boschetti, L.

2015-12-01

Systematic global burned area maps at coarse spatial resolution (350 m - 1 km) have been produced in the past two decades from several Earth Observation (EO) systems (including MODIS, Spot-VGT, AVHRR, MERIS), and have been extensively used in a variety of applications related to emissions estimation, fire ecology, and vegetation monitoring (Mouillot et al. 2014). There is however a strong need for moderate to high resolution (10-30 m) global burned area maps, in order to improve emission estimations, in particular on heterogeneous landscapes and for local scale air quality applications, for fire management and environmental restoration, and in support of carbon accounting (Hyer and Reid 2009; Mouillot et al. 2014; Randerson et al. 2012). Fires causes a non-permanent land cover change: the ash and charcoal left by the fire can be visible for a period ranging from a few weeks in savannas and grasslands ecosystems, to over a year in forest ecosystems (Roy et al. 2010). This poses a major challenge for designing a global burned area mapping system from moderate resolution (10-30 m) EO data, due to the low revisit time frequency of the satellites (Boschetti et al. 2015). As a consequence, a quantitative assessment of the permanence of the spectral signature of burned areas at global scale is a necessary step to assess the feasibility of global burned area mapping with moderate resolution sensors. This study presents a global analysis of the post-fire reflectance of burned areas, using the MODIS MCD45A1 global burned area product to identify the location and timing of burning, and the MO(Y)D09 global surface reflectance product to retrieve the time series of reflectance values after the fire. The result is a spatially explicit map of persistence of burned area signal, which is then summarized by landcover type, and by fire zone using the subcontinental regions defined by Giglio et al. (2006).

Budgets of fixed nitrogen in the Orinoco Savannah Region: Role of pyrodenitrification

NASA Astrophysics Data System (ADS)

Sanhueza, Eugenio; Crutzen, Paul J.

1998-12-01

Human activities have strongly altered the amount of fixed nitrogen that cycles in many regions of the industrialized world, with serious environmental consequences. Past studies conducted at the Orinoco savannahs of Venezuela offer a unique possibility for reviewing the cycling of nitrogen species in a tropical environment. The available information for the Orinoco savannahs is critically reviewed, and, despite many uncertainties, we present a budget analysis of both the fixed N in the soil-vegetation system and atmospheric NOy. Analysis of the data indicates that nitrogen fixation, especially by legumes, and ammonia emission from vegetation and animal wastes needs considerable attention in future research efforts. In contrast with many regions of the world, in the studied region, nonindustrial sources, foremost biomass burning, dominate the soil-vegetation and atmospheric budgets of fixed N. In general, N cycling is mainly driven by biomass burning. The resulting pyrodenitrification in the soil-vegetation system is the largest single process that, during the following wet season, may promote biological fixation to compensate for the N losses from fires during the burning season. However, a gradual impoverishment of the N status of the savannah ecosystems cannot be excluded. During the dry season, biomass burning is also the main source of atmospheric NOy, which is largely exported, mainly in the direction of the Amazon forest. Together with other nutrients, a "fertilization" of the Amazon forest due to biomass burning in the savannah may be the result. These issues require further scientific analysis.

What factors play a role in preventing self-immolation? Results from a case-control study in Iran

PubMed Central

Karim, Hosein; Schwebel, David C.; Bazargan-Hejazi, Shahrzad; Mohammadi, Reza; Choubsaz, Mansour; Heidari Zadie, Zahra; Ahmadi, Alireza

2015-01-01

Abstract: Background: To investigate factors related to prevention of self-immolation in west of Iran. Methods: In a case-control study, 30 consecutive cases of deliberate self-inflicted burns admitted to the regional burn center (Imam Khomeini hospital in Kermanshah province, Iran) were compared with controls selected from the community and matched by sex, age, district-county of residence, and rural vs urban living environment. The following characteristics relevant to preventing self-immolation were collected from all cases and controls: main domestic fuel used in the household, awareness about complications of burn injuries, and use of counseling services. Results: Descriptive analyses revealed that kerosene was the main domestic fuel in the household for 83% of cases. Not surprisingly, the main means of self-immolation in 93% of the patients was kerosene, with other fuels such as petrol and domestic gas used in remaining cases. The majority of cases and controls were aware of the potential complications of burn injuries. Use of counseling services was more common in controls. Conclusions: All three aspects of preventing self-immolation – having kerosene and other fuels in the home, being aware of the complications of burn injuries, and using counseling services were present in both the cases and controls. This suggests a large portion of residents in rural Iran are potential self-immolation victims. Increasing preventive strategies may reduce risk of suicide by self-immolation. PMID:26081518

Mass distribution and elemental analysis of the resultant atmospheric aerosol particles generated in controlled biomass burning processes

NASA Astrophysics Data System (ADS)

Ordou, N.; Agranovski, I. E.

2017-12-01

Air contamination resulting from bushfires is becoming increasingly important research question, as such disasters frequently occur in many countries. The objectives of this project were focused on physical and chemical characterisations of particulate emission resulting from burning of common representatives of Australian vegetation under controlled laboratory conditions. It was found that leaves are burned mostly with flaming phase and producing black smoke resulting in larger particles compared to white smoke in case of branches and grass, dominated by smouldering phase, producing finer particles. Following elemental analysis determined nine main elements in three different size fractions of particulate matter for each category of burning material, ranging from 14.1 μm to particle sizes below 2.54 μm. Potassium was found to be one of the main biomass markers, and sulphur was the ubiquitous element among the smoke particles followed by less prevalent trace elements like Na, Al, Mg, Zn, Si, Ca, and Fe.

Methylated spirit burns: an ongoing problem.

PubMed

Jansbeken, J R H; Vloemans, A F P M; Tempelman, F R H; Breederveld, R S

2012-09-01

Despite many educational campaigns we still see burns caused by methylated spirit every year. We undertook a retrospective study to analyse the impact of this problem. We retrospectively collected data of all patients with burns caused by methylated spirit over twelve years from 1996 to 2008. Our main endpoints were: incidence, age, mechanism of injury, total body surface area (TBSA) burned, burn depth, need for surgery and length of hospital stay. Ninety-seven patients with methylated spirit burns were included. During the study period there was no decrease in the number of patients annually admitted to the burn unit with methylated spirit burns. 28% of the patients (n=27) were younger than eighteen years old, 15% (n=15) were ten years old or younger. The most common cause of burns was carelessness in activities involving barbecues, campfires and fondues. Mean TBSA burned was 16% (SD 12.4). 70% (n=68) had full thickness burns. 66% (n=64) needed grafting. Mean length of hospital stay was 23 days (SD 24.7). The use of methylated spirit is an ongoing problem, which continues to cause severe burns in adults and children. Therefore methylated spirit should be banned in households. We suggest sale only in specialised shops, clear labelling and mandatory warnings. Copyright © 2012 Elsevier Ltd and ISBI. All rights reserved.

Epidemiologic characteristics, knowledge and risk factors of unintentional burns in rural children in Zunyi, Southwest China

PubMed Central

Shi, Shangpeng; Yang, Huajun; Hui, Ya; Zhou, Xiang; Wang, Tao; Luo, Ya; Xiang, Huiyun; Shi, Xiuquan

2016-01-01

We investigated the knowledge level and risk factors for pediatric unintentional burns in rural Southwest China with an aim to provide basic evidence for the prevention strategies. A stratified sampling method was used to recruit 1842 rural children from 9 schools. Self-reported burns during the past 12 months and relevant risk factors were collected by questionnaires. The burn incidence of all surveyed children was 12.7% (95% confidence interval [95% CI] 11.2–14.2%). We found that burn incidence had a trend to increase with the increasing school grade level and a trend to decrease with increasing knowledge scores on burns. The top two causes of burns were hot liquids (36.3%) and hot object (29.5%). More than 30% of children had little knowledge about preventive measures and how to give first-aid after burns. The main risk factors for burns included female gender, left-behind children by parents who were working in cities, and poor mother school education level. As the incidence of pediatric unintentional burns was high in rural southwest China, schools, families, and local public health agencies should put efforts into health education targeting burn prevention and first-aid measures after burns, particularly in “left-behind” children and those with mothers with poor education. PMID:27748426

The main concern of burn survivors in Iran

PubMed Central

Zamanzadeh, Vahid; Valizadeh, Lila; Lotfi, Mojgan; Salehi, Feridoon; Khalili, Assef

2016-01-01

Background: The present work was conducted to study the burn patients’ experiences to get an insight into their main concerns when they suffer the tragic event, recover from it, and adjust back in the society, so that better rehabilitation programs can be planned corresponding to their needs as well as to the needs of the society and the existing situations. Materials and Methods: In this qualitative study, 17 burn survivors were enrolled. Unstructured interviews were used for data collection. All the interviews were recorded, transcribed, and analyzed using qualitative content analysis method. Results: Based on the existing elements of the explicit textual meanings, two categories of threat and disturbance were formed. The category of threat was extracted from the following five subcategories: (a) Threat to physical life; (b) threat to the process of living; (c) psychological threat; (d) spiritual threat; and (e) social threat. The category of disturbance was extracted from the following three subcategories: (a) Sensory disturbance: Suffering pain; (b) self-concept disturbance; and (c) behavioral disturbance. Conclusions: Burn survivors experience severe pain, enduring and suffering in their daily activities after burn. Passing through these difficult trajectories is perceived as a threat and disturbance in self-integrity. PMID:27563326

Post-wildfire natural restoration of riparian vegetation under stable hydro-geomorphic conditions: Nahal Grar, Northern Negev Desert, Israel

NASA Astrophysics Data System (ADS)

Egozi, Roey

2015-04-01

Wildfires are common to the Mediterranean region due to its defined dry season and long historical anthropogenic activities. Most of post-wildfire studies focus on mountains areas and thus refer to the hill-slope and its physical characteristics, e.g. morphology, length, angles, and aspect; its soil characteristics, e.g. type, infiltration rate, repellency; and its vegetative covers, e.g. planted trees vs. natural forest or native vs. exotic vegetation. In contrary there is very limited literature focusing on ecological and hydro-geomorphic aspects of post-wildfire of riparian vegetation / zone probably because of its negligible burned area relative to the spread of the fire, sometimes, over the whole watershed area. The limited literature on the topic is surprising given the fact that riparian vegetation zone has been acknowledged as a unique and important habitat supporting rich biodiversity. Herein we report on a wildfire event occurred on October 14th 2009 in a river section of Nahal Grar, Northern Negev Desert, Israel. The wildfire although was limited in its area (only 3 hectare) extended over the channel alone from bank to bank and thus provide a unique case study of completely burn down of riparian vegetation, mainly dense stands of Common Red (Australis Phragmites. Therefore a detailed study of this event provides an opportunity to tackle one of the basics questions which is determining the rate of natural restoration process that act at the immediate time after the wildfire event occurred. This type of information is most valuable to professional and stakeholders for better management of post-fire riparian zones. The results of the study suggest that under stable conditions, i.e. no major flood events occurred; disturbance time was short and ranged over 200 days due to, almost, immediate recovery of the riparian vegetation. However the re-growth of the riparian vegetation was not even but rather deferential and more complex then reported in the literature. In addition during that period no morphological changes were measured in the channel bed and banks; similarly no changes observed to base flow discharge though slight changes were measured to water pH probably due to the large quantities of ash on river bed.

The Attack on Psychosomatic Integrity: a Study of the Psychological Sequelae of Burn Trauma

PubMed Central

Cavaleri, V.; Epifanio, M.S.; Benigno, A.; Conte, F.; Di Pasquale, A.

2009-01-01

Summary Burns pathology is characterized not only by insidious damage to the patients' outward appearance but also by the equally painful emotional difficulties they encounter as they reorganize their identity and their personal history. This exploratory survey, combining research work with medical action, considers the cases of 41 outpatients who were hospitalized and subjected to skin grafting. The patients were recruited through the database of the Palermo Civic Hospital Plastic Surgery and Burns Therapy Operative Unit. The questionnaires were compiled 6 and 12 months post-burn (12 months' observation). The main objective of the research was to investigate the quality of life of burn patients in relation to the way they handled their condition on the emotional level, in order to cope with the stress caused by the burn. PMID:21991160

Evaluation of the Effects of Honey on Acute-Phase Deep Burn Wounds

PubMed Central

Nakajima, Yukari; Mukai, Kanae; Nasruddin; Komatsu, Emi; Iuchi, Terumi; Kitayama, Yukie; Sugama, Junko; Nakatani, Toshio

2013-01-01

This study aimed to clarify the effects of honey on acute-phase deep burn wounds. Two deep burn wounds were created on mice which were divided into four groups: no treatment, silver sulfadiazine, manuka honey, and Japanese acacia honey. Wound sizes were calculated as expanded wound areas and sampled 30 minutes and 1–4 days after wounding for histological observation. The wound sections were subjected to hematoxylin and eosin and immunohistological staining to detect necrotic cells, apoptotic cells, neutrophils, and macrophages. The no treatment group formed a scar. The redness around the wound edges in the silver sulfadiazine group was the most intense. All groups exhibited increased wound areas after wounding. The proportions of necrotic cells and the numbers of neutrophils in the manuka and acacia honey groups were lower than those in the no treatment and silver sulfadiazine groups until day 3; however, there were no significant differences between all groups on day 4. These results show that honey treatment on deep burn wounds cannot prevent wound progression. Moreover, comparing our observations with those of Jackson, there are some differences between humans and animals in this regard, and the zone of hyperemia and its surrounding area fall into necrosis, which contributes to burn wound progression. PMID:24348720

A porcine deep dermal partial thickness burn model with hypertrophic scarring.

PubMed

Cuttle, Leila; Kempf, Margit; Phillips, Gael E; Mill, Julie; Hayes, Mark T; Fraser, John F; Wang, Xue-Qing; Kimble, Roy M

2006-11-01

We developed a reproducible model of deep dermal partial thickness burn injury in juvenile Large White pigs. The contact burn is created using water at 92 degrees C for 15s in a bottle with the bottom replaced with plastic wrap. The depth of injury was determined by a histopathologist who examined tissue sections 2 and 6 days after injury in a blinded manner. Upon creation, the circular wound area developed white eschar and a hyperaemic zone around the wound border. Animals were kept for 6 weeks or 99 days to examine the wound healing process. The wounds took between 3 and 5 weeks for complete re-epithelialisation. Most wounds developed contracted, purple, hypertrophic scars. On measurement, the thickness of the burned skin was approximately 1.8 times that of the control skin at week 6 and approximately 2.2 times thicker than control skin at 99 days after injury. We have developed various methods to assess healing wounds, including digital photographic analysis, depth of organising granulation tissue, immunohistochemistry, electron microscopy and tensiometry. Immunohistochemistry and electron microscopy showed that our porcine hypertrophic scar appears similar to human hypertrophic scarring. The development of this model allows us to test and compare different treatments on burn wounds.

Evaluation of the effects of honey on acute-phase deep burn wounds.

PubMed

Nakajima, Yukari; Mukai, Kanae; Nasruddin; Komatsu, Emi; Iuchi, Terumi; Kitayama, Yukie; Sugama, Junko; Nakatani, Toshio

2013-01-01

This study aimed to clarify the effects of honey on acute-phase deep burn wounds. Two deep burn wounds were created on mice which were divided into four groups: no treatment, silver sulfadiazine, manuka honey, and Japanese acacia honey. Wound sizes were calculated as expanded wound areas and sampled 30 minutes and 1-4 days after wounding for histological observation. The wound sections were subjected to hematoxylin and eosin and immunohistological staining to detect necrotic cells, apoptotic cells, neutrophils, and macrophages. The no treatment group formed a scar. The redness around the wound edges in the silver sulfadiazine group was the most intense. All groups exhibited increased wound areas after wounding. The proportions of necrotic cells and the numbers of neutrophils in the manuka and acacia honey groups were lower than those in the no treatment and silver sulfadiazine groups until day 3; however, there were no significant differences between all groups on day 4. These results show that honey treatment on deep burn wounds cannot prevent wound progression. Moreover, comparing our observations with those of Jackson, there are some differences between humans and animals in this regard, and the zone of hyperemia and its surrounding area fall into necrosis, which contributes to burn wound progression.

Generalized Pseudo-Reaction Zone Model for Non-Ideal Explosives

NASA Astrophysics Data System (ADS)

Wescott, B. L.

2007-12-01

The pseudo-reaction zone model was proposed to improve engineering scale simulations with high explosives that have a slow reaction component. In this work an extension of the pseudo-reaction zone model is developed for non-ideal explosives that propagate well below the steady-planar Chapman-Jouguet velocity. A programmed burn method utilizing Detonation Shock Dynamics (DSD) and a detonation velocity dependent pseudo-reaction rate has been developed for non-ideal explosives and applied to the explosive mixture of ammonium nitrate and fuel oil (ANFO). The pseudo-reaction rate is calibrated to the experimentally obtained normal detonation velocity—shock curvature relation. Cylinder test simulations predict the proper expansion to within 1% even though significant reaction occurs as the cylinder expands.

Space images processing methodology for assessment of atmosphere pollution impact on forest-swamp territories

NASA Astrophysics Data System (ADS)

Polichtchouk, Yuri; Tokareva, Olga; Bulgakova, Irina V.

2003-03-01

Methodical problems of space images processing for assessment of atmosphere pollution impact on forest ecosystems using geoinformation systems are developed. An approach to quantitative assessment of atmosphere pollution impact on forest ecosystems is based on calculating relative squares of forest landscapes which are inside atmosphere pollution zones. Landscape structure of forested territories in the southern part of Western Siberia are determined on the basis of procession of middle resolution space images from spaceborn Resource-O. Particularities of atmosphere pollution zones modeling caused by gas burning in torches on territories of oil fields are considered. Pollution zones were revealed by modeling of contaminants dispersal in atmosphere with standard models. Polluted landscapes squares are calculated depending on atmosphere pollution level.

Human Mars Mission Performance Crew Taxi Profile. Part 1

NASA Technical Reports Server (NTRS)

Duaro, Vince A.

1999-01-01

This timeline was generated on the Integrated Mission Program (IMP). All burn events over 2 seconds are finite with IMP solving a two point boundary value setup for begin burn time, burn time and control angles. Perigee and apogee shown above are mean orbital values. Significant events are listed. Each finite thrust event has two lines. The first is the beginning time showing the initial conditions, thrust and ISP used. The second has the end burn conditions and the delta v and time of burn. This case is an abort from the 750 x 750 phasing abort, using the taxi's main engines. An abort using the Reaction Control System (RCS) was also investigated but required a large increase in RCS propellant and was abandoned.

3D hydrodynamic simulations of carbon burning in massive stars

NASA Astrophysics Data System (ADS)

Cristini, A.; Meakin, C.; Hirschi, R.; Arnett, D.; Georgy, C.; Viallet, M.; Walkington, I.

2017-10-01

We present the first detailed 3D hydrodynamic implicit large eddy simulations of turbulent convection of carbon burning in massive stars. Simulations begin with radial profiles mapped from a carbon-burning shell within a 15 M⊙ 1D stellar evolution model. We consider models with 1283, 2563, 5123, and 10243 zones. The turbulent flow properties of these carbon-burning simulations are very similar to the oxygen-burning case. We performed a mean field analysis of the kinetic energy budgets within the Reynolds-averaged Navier-Stokes framework. For the upper convective boundary region, we find that the numerical dissipation is insensitive to resolution for linear mesh resolutions above 512 grid points. For the stiffer, more stratified lower boundary, our highest resolution model still shows signs of decreasing sub-grid dissipation suggesting it is not yet numerically converged. We find that the widths of the upper and lower boundaries are roughly 30 per cent and 10 per cent of the local pressure scaleheights, respectively. The shape of the boundaries is significantly different from those used in stellar evolution models. As in past oxygen-shell-burning simulations, we observe entrainment at both boundaries in our carbon-shell-burning simulations. In the large Péclet number regime found in the advanced phases, the entrainment rate is roughly inversely proportional to the bulk Richardson number, RiB (∝RiB-α, 0.5 ≲ α ≲ 1.0). We thus suggest the use of RiB as a means to take into account the results of 3D hydrodynamics simulations in new 1D prescriptions of convective boundary mixing.

Accounting for Mass Transfer Kinetics when Modeling the Impact of Low Permeability Layers in a Groundwater Source Zone on Dissolved Contaminant Fate and Transport

DTIC Science & Technology

2014-03-27

Clay Interface) ...................................................................................................... 40 Figure 9: Time-Dependent...vs Constant Dissolution Rate BTCs (Monitoring Well in Clay ...pits, poured down sanitary sewer systems, and partially burned in fire training pits. Poor handling and disposal of chlorinated solvents have

76 FR 64820 - Safety Zone; Mainardi/Kinsey Wedding Fireworks, Lake Erie, Lakewood, OH

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-19

... detonations, dangerous detonations, dangerous projectiles, and falling or burning debris that may cause death... cause finds that those procedures are ``impracticable, unnecessary, or contrary to the public interest.'' Under 5 U.S.C. 553(b)(B), the Coast Guard finds that good cause exists for not publishing a notice of...

14 CFR 25.1193 - Cowling and nacelle skin.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Cowling and nacelle skin. 25.1193 Section... and nacelle skin. (a) Each cowling must be constructed and supported so that it can resist any... openings or by burning through external skin, any other zone or region where it would create additional...

Burn hazards of the deployed environment in wartime: epidemiology of noncombat burns from ongoing United States military operations.

PubMed

Kauvar, David S; Wade, Charles E; Baer, David G

2009-10-01

Service in the deployed military environment carries risks for accidental (noncombat-related) burns. Examining these risks can assist in the development of military burn prevention measures. This study endeavored to examine noncombat burn epidemiology in the context of similar civilian data. We performed a retrospective cohort study of consecutive casualties evacuated from operational military theaters in Iraq and Afghanistan to the sole tertiary military burn center in the US. Military data were compared with database samples of the US population from the American Burn Association and the Centers for Disease Control and Prevention. The main causes of the 180 noncombat burns seen from March 2003 to June 2008 were waste burning, fuel mishaps, and unintentional ordinance detonations. Overall prevalence of noncombat burns was 19.5 burns/100,000 person-years lived. If causes specific to military operations are removed, military prevalence was 13.0/100,000. More than one-third of noncombat burns occurred in the first year of the study; a period of stability followed. A similar US population had an accidental burn prevalence of 7.1/100,000 from 2003 to 2007. Burn size, presence of inhalation injury, and burn center mortality were not different from those in a similar civilian cohort. Deployed service members have a greater risk of unintentional burns than a similar civilian cohort does. This is in part because of the specific dangers of military activities. More attention to deployed military burn prevention is needed, especially early in combat support operations.

[Plant communities in the terrestrial-aquatic transition zone in the paramo of Chingaza, Colombia].

PubMed

Schmidt-Mumm, Udo; Vargas Ríos, Orlando

2012-03-01

Plant communities in the terrestrial-aquatic transition zone in the paramo of Chingaza, Colombia. High Andean paramo ecosystems are an important water resource for many towns, and major cities in this region. The aquatic and wetland vegetation of different paramo lakes, pond, swamps and bogs was studied according to the classical phytosociological approach, which is based on homogenous stands, but excludes any border phenomena or transitional zone. The present research aimed at determining the aquatic and wetland vegetation along different moisture gradients. A total of 89 species in 30 transects were reported, of which Crassula venezuelensis, Carex honplandii, Callitriche nubigena, Eleocharis macrostachya, Ranunculus flagelliformis, R. nubigenus, Eleocharis stenocarpa, Galium ascendens y Alopecurus aequalis were present in more than one third of the transects. Numerical classification and indicator species analysis resulted in the definition of the next 18 communities: 1) Calamagrostis effusa, 2) Sphagnum cuspidatum, 3) Cyperus rufus, 4) Eleocharis stenocarpa, 5) Carex acutata, 6) Poa annua,7) Valeriana sp., 8) Ranunculus flagelliformis, 9) Carex bonplandii, 10) Festuca andicola. 11) Muhlenbergia fustigiata, 12) Elatine paramoana, 13) Isoëtes palmeri, 14) Crassula venezuelensis, 15) Lilaeopsis macloviana, 16) Callitriche nubigena, 17) Potamogeton paramoanus and 18) Potamogeton illinoensis. The ordination of communities reveals the presence of three different aquatic-terrestrial gradients which are related to the life form structure of species that characterized the various communities. We concluded that patchiness and heterogeneity of the vegetation is mainly the result of alterations caused by human activities (burning, cattle raise and material extraction for road and dam construction).

Characterization of ignition transient processes in kerosene-fueled model scramjet engine by dual-pulse laser-induced plasma

NASA Astrophysics Data System (ADS)

Li, Xipeng; Liu, Weidong; Pan, Yu; Yang, Leichao; An, Bin; Zhu, Jiajian

2018-03-01

Dual-pulse laser-induced plasma ignition of kerosene in cavity at model scramjet engine is studied. The simulated flight condition is Ma 6 at 30 km, and the isolator entrance has a Mach number of 2.92, a total pressure of 2.6 MPa and a stagnation temperature of 1650 K. Two independent laser pulses at 532 nm with a pulse width of 10 ns, a diameter of 12 mm and a maximum energy of 300 mJ are focused into cavity for ignition. The flame structure and propagation during transient ignition processes are captured by simultaneous CH* and OH* chemiluminescence imaging. The entire ignition process of kerosene can be divided into five stages, which are referred as turbulent dissipation stage, quasi-stable state, combustion enhancement stage, reverting stage and combustion stabilization stage. A local closed loop of propagations of the burning mixtures from the shear layer into the recirculation zone of cavity is revealed, which the large-scale eddy in the shear layer plays a key role. The enhancement of mass exchange between shear layer and the recirculation zone of cavity could promote the flame propagation process and enhance the ignition capability as well as extend the ignition limits. A cavity shear-layer stabilized combustion of kerosene is established in the supersonic flow roughly 3.3 ms after the laser pulse. Chemical reactions mainly occur in the shear layer and the near-wall zone downstream of the cavity. The distribution of OH* is thicker than CH* at stable combustion condition.

SO2 damage to forests recorded by ERTS-1. [Ontario, Canada

NASA Technical Reports Server (NTRS)

Murtha, P. A.

1974-01-01

Sulfur dioxide fumes have been affecting the forests around Wawa, Ontario, which have been under surveillance for a number of years and were recently covered by ultra-small-scale (1:160,000) air photography for damage-assessment purposes. Image interpretation supported by electronic color enhancement was used to delineate on ERTS imagery three damage zones (total-kill, heavy-kill and medium-damage zones). The zones delineated on ERTS imagery are similar to the results of aerial sketch-mapping and air photo interpretation. Band 5 provided the greatest detail for assessing the damage to the forests, followed in successive order by bands 4, 6 and 7. Comparison with ERTS images obtained in the winter showed that even though the total-kill could be separated from heavy-kill damage zones, total-kill could not be consistently separated from clear-cut logging, burned areas, frozen lakes and bogs.

Oil shale retorting and combustion system

DOEpatents

Pitrolo, Augustine A.; Mei, Joseph S.; Shang, Jerry Y.

1983-01-01

The present invention is directed to the extraction of energy values from l shale containing considerable concentrations of calcium carbonate in an efficient manner. The volatiles are separated from the oil shale in a retorting zone of a fluidized bed where the temperature and the concentration of oxygen are maintained at sufficiently low levels so that the volatiles are extracted from the oil shale with minimal combustion of the volatiles and with minimal calcination of the calcium carbonate. These gaseous volatiles and the calcium carbonate flow from the retorting zone into a freeboard combustion zone where the volatiles are burned in the presence of excess air. In this zone the calcination of the calcium carbonate occurs but at the expense of less BTU's than would be required by the calcination reaction in the event both the retorting and combustion steps took place simultaneously. The heat values in the products of combustion are satisfactorily recovered in a suitable heat exchange system.

30 CFR 19.9 - Performance.

Code of Federal Regulations, 2010 CFR

2010-07-01

... MINING PRODUCTS ELECTRIC CAP LAMPS § 19.9 Performance. In addition to the general design and the safety... respect to performance, as follows: (a) Time of burning and candlepower. Permissible electric cap lamps.... The life of a bulb is the number of hours its main filament will burn in the cap lamp or its...

Feet sunk in molten aluminium: The burn and its prevention.

PubMed

Alonso-Peña, David; Arnáiz-García, María Elena; Valero-Gasalla, Javier Luis; Arnáiz-García, Ana María; Campillo-Campaña, Ramón; Alonso-Peña, Javier; González-Santos, Jose María; Fernández-Díaz, Alaska Leonor; Arnáiz, Javier

2015-08-01

Nowadays, despite improvements in safety rules and inspections in the metal industry, foundry workers are not free from burn accidents. Injuries caused by molten metals include burns secondary to molten iron, aluminium, zinc, copper, brass, bronze, manganese, lead and steel. Molten aluminium is one of the most common causative agents of burns (60%); however, only a few publications exist concerning injuries from molten aluminium. The main mechanisms of lesion from molten aluminium include direct contact of the molten metal with the skin or through safety apparel, or when the metal splash burns through the pants and rolls downward along the leg. Herein, we report three cases of deep dermal burns after 'soaking' the foot in liquid aluminium and its evolutive features. This paper aims to show our experience in the management of burns due to molten aluminium. We describe the current management principles and the key features of injury prevention. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

Fungal infections in burns: a comprehensive review

PubMed Central

Struck, M.F.; Gille, J.

2013-01-01

Summary Burn wound infections remain the most important factor limiting survival in burn intensive care units. Large wound surface, impaired immune systems, and broad-spectrum antibiotic therapy contribute to the growth of opportunistic fungal species. Faced with challenging fluid resuscitation, wound excision and cardiopulmonary stabilization, mycosis in burns are likely to be underestimated. Diagnostic performance can sometimes be delayed because clinical signs are unspecific and differentiation between colonization and infection is difficult. Therapeutic measures range from infection prophylaxis over treatment with antifungal agents towards radical amputation of infected limbs. New methods of early and reliable detection of fungal organisms, as well as the use of novel antifungal substances, are promising but require wider establishment to confirm the beneficial effects in burn patients. This review aims to highlight the main important aspects of fungal infections in burns including incidence, infection control, diagnostic and therapeutic approaches, prognosis and outcomes. PMID:24563641

Epidemiology and outcome analysis of hand burns: A 5-year retrospective review of 378 cases in a burn center in Eastern China.

PubMed

Wang, Kang-an; Sun, Yu; Wu, Guo-sheng; Wang, Yi-ru; Xia, Zhao-fan

2015-11-01

Hands are frequent sites of burn but few related studies were reported in China. The aim of this study was to examine the impacts of gender, age, seasons, place, etiology, total body surface area (TBSA), depth, infection and comorbidities on prognosis following injury in a cohort of hand burn inpatients. This is a retrospective study of total 378 inpatients admitted to the burn center of Changhai hospital from January 2009 to December 2013. The present research showed the male inpatients were predominant and most of the inpatients aged from 20 to 49. Flame (37.04%) and electricity (25.40%) were the major causes of hand burns. Hand burns happened more commonly in work place (60.85%). The study preliminarily pointed out that male, flame and depth were the most significant factors impacting surgery. The main factors relevant to amputation were identified including the electrical burns and other etiology of burns. In addition, depth of hand burns was proved to have a higher impact on length of hospital stay (LOS) than other factors. The results of this study not only provide the necessary information of hand burns in Eastern China but also give the suggestions for the prevention of hand burns. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

Fluid dynamics of the unsteady two phase processes leading to DDT in granular solid propellants

NASA Technical Reports Server (NTRS)

Krier, H.; Butler, P. B.; Lembeck, M. F.

1980-01-01

Deflagration to Detonation (DDT) was predicted to occur in porous beds of high-energy solid propellants by solving the unsteady fluid mechanical convective heat transfer from hot gas products, obtained from the rapid burning at high pressures, provides the impetus to develop a narrow combustion zone and a resulting strong shock. A parametric study clearly indicates that DDT occurs only when a combination of the solids loading fraction, the burning rate constants, the propellant chemical energy, and the particle size provide for critical energy and gas release to support a detonation wave. Predictions for the run-up length to detonation as a function of these parameters are presented.

No herbicide residues found in smoke from prescribed fires

Treesearch

Charles K. McMahon; Parshall B. Bush

1992-01-01

Some concerns have been expressed by workers conducting prescribed burns on forest lands treated with herbicides.The major concern has based on speculation that hazardous levels of airborne herbicide residues may be present in the smoke near breathing zones of forest workers. Much of this speculation is based on fire hazard caution statements found on product labels...

Wildfire and Oak Regeneration at the Urban Fringe

Treesearch

Joan L. Schwan; Herb Fong; Hilary K. Hug

1997-01-01

In July 1992, wildfire burned 500 acres of rural lands owned by Stanford University. Within the fire zone are five plots, ranging in size from 0.1 acre to more than 1 acre, on which nearly 600 naturally established juvenile California oaks (Q. agrifolia, Q. douglasii, and Q. lobata) have been monitored since 1990. Surveys following...

Fire severity in intermittent stream drainages, Western Cascade Range, Oregon.

Treesearch

Jennifer E. Tollefson; Frederick J. Swanson; John H. Cissel

2004-01-01

We quantified fire severity patterns within intermittent stream drainages in a recently burned area of the central western Cascades, Oregon. Aerial photographs were used to estimate post fire live canopy cover within streamside and upland zones on the southeast and southwest-facing slopes of 33 watersheds. Live canopy cover did not differ significantly between...

NanoSIMS isotope studies of rare types of presolar silicon carbide grains from the Murchison meteorite: Implications for supernova models and the role of 14C

NASA Astrophysics Data System (ADS)

Hoppe, Peter; Pignatari, Marco; Kodolányi, János; Gröner, Elmar; Amari, Sachiko

2018-01-01

We have conducted a NanoSIMS ion imaging survey of about 1800 presolar silicon carbide (SiC) grains from the Murchison meteorite. A total of 21 supernova (SN) X grains, two SN C grains, and two putative nova grains were identified. Six particularly interesting grains, two X and C grains each and the two putative nova grains were subsequently studied in greater detail, namely, for C-, N-, Mg-Al-, Si-, S-, and Ca-Ti-isotopic compositions and for the initial presence of radioactive 26Al (half life 716,000 yr), 32Si (half life 153 yr), and 44Ti (half life 60 yr). Their isotope data along with those of three X grains from the literature were compared with model predictions for 15 M⊙ and 25 M⊙ Type II supernovae (SNe). The best fits were found for 25 M⊙ SN models that consider for the He shell the temperature and density of a 15 M⊙ SN and ingestion of H into the He shell before the explosion. In these models a C- and Si-rich zone forms at the bottom of the He burning zone (C/Si zone). The region above the C/Si zone is termed the O/nova zone and exhibits the isotopic fingerprints of explosive H burning. Satisfactory fits of measured C-, N-, and Si-isotopic compositions and of 26Al/27Al ratios require small-scale mixing of matter originating from a region extending over 0.2 M⊙ for X and C grains and over 0.4 M⊙ for one of the putative nova grains, involving matter from a thin Si-rich layer slightly below the C/Si zone, the C/Si zone, and the O/nova zone. Simultaneous fitting of 14N/15N and 26Al/27Al requires a C-N fractionation of a factor of 50 during SiC condensation. This leads to preferential incorporation of radioactive 14C (half life 5700 yr) over directly produced 14N and can account for the 14N/15N along with 26Al/27Al ratios as observed in the SiC grains. The good fit for one of the putative nova grains along with its high 26Al/27Al points towards a SN origin and supports previous suggestions that some grains classified as nova grains might be from SNe. Apparent problems with the small-scale mixing scheme considered here are C/O ratios that are mostly <1 if C-, N-, and Si-isotopic compositions and 26Al/27Al ratios are simultaneously matched, underproduction of 32Si, and overproduction of 44Ti. This confirms the limitations of one-dimensional hydrodynamical models for H ingestion and stresses the need to better study the convective-boundary mixing mechanisms at the bottom of the convective He shell in massive star progenitors. This is crucial to define the effective size of the C/Si zone formed by the SN shock. The comparison between the Si isotope data of the SN grains and the models gives a hint that the predicted 30Si is too high at the bottom of the He burning shell.

Alternative Conceptions about Burning Held by Atayal Indigene Students in Taiwan

ERIC Educational Resources Information Center

Chang, Jen-Min; Lee, Huei; Yen, Chiung-Fen

2010-01-01

The purpose of this study was to investigate the alternative conceptions about burning phenomena among Atayal indigene elementary school students in Taiwan. The main difference from other relevant research is that this study assesses Atayal people's worldview by means of a questionnaire developed specifically for this purpose. There were three…

MORBIDITY AND SURVIVAL PROBABILITY IN BURN PATIENTS IN MODERN BURN CARE

PubMed Central

Jeschke, Marc G.; Pinto, Ruxandra; Kraft, Robert; Nathens, Avery B.; Finnerty, Celeste C.; Gamelli, Richard L.; Gibran, Nicole S.; Klein, Matthew B.; Arnoldo, Brett D.; Tompkins, Ronald G.; Herndon, David N.

2014-01-01

Objective Characterizing burn sizes that are associated with an increased risk of mortality and morbidity is critical because it would allow identifying patients who might derive the greatest benefit from individualized, experimental, or innovative therapies. Although scores have been established to predict mortality, few data addressing other outcomes exist. The objective of this study was to determine burn sizes that are associated with increased mortality and morbidity after burn. Design and Patients Burn patients were prospectively enrolled as part of the multicenter prospective cohort study, Inflammation and the Host Response to Injury Glue Grant, with the following inclusion criteria: 0–99 years of age, admission within 96 hours after injury, and >20% total body surface area burns requiring at least one surgical intervention. Setting Six major burn centers in North America. Measurements and Main Results Burn size cutoff values were determined for mortality, burn wound infection (at least two infections), sepsis (as defined by ABA sepsis criteria), pneumonia, acute respiratory distress syndrome, and multiple organ failure (DENVER2 score >3) for both children (<16 years) and adults (16–65 years). Five-hundred seventy-three patients were enrolled, of which 226 patients were children. Twenty-three patients were older than 65 years and were excluded from the cutoff analysis. In children, the cutoff burn size for mortality, sepsis, infection, and multiple organ failure was approximately 60% total body surface area burned. In adults, the cutoff for these outcomes was lower, at approximately 40% total body surface area burned. Conclusions In the modern burn care setting, adults with over 40% total body surface area burned and children with over 60% total body surface area burned are at high risk for morbidity and mortality, even in highly specialized centers. PMID:25559438

Characteristics of Polybrominated Diphenyl Ethers Released from Thermal Treatment and Open Burning of E-Waste.

PubMed

Li, Ting-Yu; Zhou, Jun-Feng; Wu, Chen-Chou; Bao, Lian-Jun; Shi, Lei; Zeng, Eddy Y

2018-04-17

Primitive processing of e-waste potentially releases abundant organic contaminants to the environment, but the magnitudes and mechanisms remain to be adequately addressed. We conducted thermal treatment and open burning of typical e-wastes, that is, plastics and printed circuit boards. Emission factors of the sum of 39 polybrominated diphenyl ethers (∑ 39 PBDE) were 817-1.60 × 10 5 ng g -1 in thermal treatment and nondetected-9.14 × 10 4 ng g -1 , in open burning. Airborne particles (87%) were the main carriers of PBDEs, followed by residual ashes (13%) and gaseous constituents (0.3%), in thermal treatment, while they were 30%, 43% and 27% in open burning. The output-input mass ratios of ∑ 39 PBDE were 0.12-3.76 in thermal treatment and 0-0.16 in open burning. All PBDEs were largely affiliated with fine particles, with geometric mean diameters at 0.61-0.83 μm in thermal degradation and 0.57-1.16 μm in open burning from plastic casings, and 0.44-0.56 and nondetected- 0.55 μm, from printed circuit boards. Evaporation and reabsorption may be the main emission mechanisms for lightly brominated BDEs, but heavily brominated BDEs tend to affiliate with particles from heating or combustion. The different size distributions of particulate PBDEs in emission sources and adjacent air implicated a noteworthy redisposition process during atmospheric dispersal.

Exposure risk to carcinogenic PAHs in indoor-air during biomass combustion whilst cooking in rural India

NASA Astrophysics Data System (ADS)

Bhargava, Anuj; Khanna, R. N.; Bhargava, S. K.; Kumar, Sushil

In India, a vast majority of rural household burns unprocessed biomass, as an energy source, to cook food. The biomass is burnt indoors in conventionally homemade clay-stoves, called 'Chulha', which results in the generation of a variety of airborne products along with polycyclic aromatic hydrocarbons (PAHs) in an uncontrolled manner. We report here the concentrations and profile of carcinogenic PAHs, co-sampled with respirable suspended particulate matter, in rural indoors during burning of biomass vis-à-vis liquified petroleum gas as the energy source. There is a limited data on the subject in the literature. The seasonal variation has also been studied. Sampling was done in breathing zone and in surrounding areas concurrent with cooking on chulha. PAHs were extracted in methylene chloride and analyzed over HPLC after column clean up on silica gel. Our study revealed that the concentrations of carcinogenic PAHs were fairly high in breathing zone and in surrounding areas while cooking over chulha in rural India. PAHs concentrations increased substantially during biomass combustion. Concentrations were high during CDC combustion and low during LPG combustion or the non-cooking period. This trend was conserved in both the seasons. Concentrations of total PAHs were greater in winter as compared to summer and greatest in the breathing zone. Di-benz( a,h)anthracene, benzo( k)-fluoranthene and chrysene contributed maximum. Benzo( a)pyrene contributed moderately. Maximum concentrations of indoor air benzo( a)pyrene (>1.5 μg/m 3) were found in breathing zone in winter. The daily exposure to high concentrations of carcinogenic PAHs in indoor air environment while cooking food could be impacting for chronic pulmonary illnesses in rural Indian women.

Patterns of burns and scalds in Mongolian children: a hospital-based prospective study.

PubMed

Gerelmaa, Gunsmaa; Tumen-Ulzii, Badarch; Nakahara, Shinji; Ichikawa, Masao

2018-03-01

To describe the circumstances of burn injury occurrence among Mongolian children and the products involved. Study participants were children aged 15 years and younger who were admitted to the Burn Unit of the National Trauma Orthopedic Research Center from August 2015 to July 2016. We collected data on participant demographics and the aetiology and clinical features of their burn injuries, and we analysed the data based on the NOMESCO Classification model. Of 906 children, 83% were aged 0-3 years, 66% were injured around the cooking area in the traditional tent-like dwelling called a ger or a detached house where no specified kitchen exists, and 28% were injured in a kitchen. Burn injuries resulted mostly from exposure to overflowing hot liquids (93%). Electric pots and electric kettles were the products most frequently involved in causing burn injuries (41% and 14%, respectively). Of 601 major burn injuries, 52% were due to electric pots. Moreover, burn injuries inflicted by electric pots were most likely to be major burn injuries (83%). Children typically fell into electric pots, while electric kettles were often pulled down by children. Burn injuries among Mongolian children mainly occurred in cooking area of a ger involving electric pots. The current practice of cooking on the floor should be reconsidered for child burn prevention. © 2018 John Wiley & Sons Ltd.

Particulate matter characteristics during agricultural waste burning in Taichung City, Taiwan.

PubMed

Cheng, Man-Ting; Horng, Chuen-Liang; Su, Yi-Ru; Lin, Li-Kai; Lin, Yu-Chi; Chou, Charles C-K

2009-06-15

Agricultural waste burning is performed after harvest periods in June and November in Taiwan. Typically, farmers use open burning to dispose of excess rice straw. PM(2.5) and PM(2.5-10) measurements were conducted at National Chung Hsing University in Taichung City using a dichotomous sampler. The sampling times were during straw burning periods after rice harvest during 2002-2005. Ionic species including SO(4)(2-), NO(3)(-), NH(4)(+), K(+), Ca(2+), Cl(-) and Na(+) and carbonaceous species (EC and OC) in PM(2.5) and PM(2.5-10) were analyzed. The results showed that the average PM(2.5) and PM(2.5-10) concentrations were 123.6 and 31.5 microg m(-3) during agricultural waste burning periods and 32.6 and 21.4 microg m(-3) during non-waste burning periods, respectively. The fine aerosol ionic species including Cl(-), K(+) and NO(3)(-) increased 11.0, 6.7 and 5.5 times during agricultural burning periods compared with periods when agricultural waste burning is not performed. K(+) was found mainly in the fine mode during agricultural burning. High nitrogen oxidation ratio was found during agricultural waste burning periods which might be caused by the conversion of Nitrogen dioxide (NO(2)) to NO(3)(-). It is concluded that agricultural waste burning with low dispersion often causes high PM(2.5) and gases pollutant events.

Rehabilitation and social adjustment of people with burns in society.

PubMed

Din, Sirajud; Shah, Mussawar; Asadullah; Jamal, Humera; Bilal, Muhammad

2015-02-01

The present study was conducted on rehabilitation and social adjustment of people with burns in society with the main objective to determine the relationship between social adjustment of people with burns and their psychosocial rehabilitation. The study was limited to the Burn Unit, Khyber Teaching Hospital, Peshawar, Pakistan. At bi-variate level, the following were observed: the relationship of psychosocial rehabilitation was highly significant (P=0.000) considering that people with burns feel shame in the society, a highly significant relation (P=0.000) was found between psychosocial rehabilitation and burn as the hurdle to contact other members of the society, a highly significant (P=0.000) relation was found between psychosocial rehabilitation and perception that society provides social support to people with burns, a highly significant (P=0.000) relationship between psychosocial rehabilitation and people with burns feel alienated from the society, a significant association (P=0.024) was found between psychosocial rehabilitation and loss of social network, and a significant (P=0.002) association between psychosocial rehabilitation and society insult toward people with burns. Regular provision of treatment, quota in job allocation for people with burns, initiation of stipend through Benazir Income Support Program, and keeping and updating record of burns at the district level in census centers were suggested as recommendations in light of the study. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

Determinants of burn first aid knowledge: Cross-sectional study.

PubMed

Wallace, Hilary J; O'Neill, Tomas B; Wood, Fiona M; Edgar, Dale W; Rea, Suzanne M

2013-09-01

This study investigated demographic factors, experience of burn/care and first aid course attendance as factors influencing burn first aid knowledge. A cross-sectional study was undertaken using convenience sampling of members of sporting and recreation clubs. The main outcome measure was the proportion of correct responses to multiple-choice questions relating to four burn scenarios: (1) scald, (2) contact burn, (3) ignited clothing, and (4) chemical burn. A total of 2602 responses were obtained. Large gaps (30-50% incorrect answers) were identified in burn first aid knowledge across all scenarios. 15% more individuals gave correct answers if they had attended a first aid course compared to those who had not (p<0.0001); this proportion increased if the course was undertaken within the previous five years (p<0.0001) or contained a burns-specific component (p<0.0001). Males and younger (≤25 years) and older (≥65 years) age-groups had relatively lower levels of burn first aid knowledge. Gender and age were significant predictors of first aid course attendance, with males and younger (≤25 years) and older (≥65 years) age-groups less likely to have attended a first aid course. In this sample, first aid training undertaken within the last 5 years with a specific burns component was associated with enhanced burn first aid knowledge. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

Evaluation of burn injuries related to liquefied petroleum gas.

PubMed

Tarim, Mehmet Akin

2014-01-01

Liquefied petroleum gas (LPG) is a fuel that is widely used for domestic, agricultural, and industrial purposes. LPG is also commonly used in restaurants, industries, and cars; however, the home continues to be the main site for accidents. In Turkey, the increased usage of LPG as a cooking or heating fuel has resulted in many burn injuries from LPG mishaps. Between January 2000 and June 2011, 56 LPG-burned patients were compared with 112 flame-burned patients. There were no significant differences with respect to the mean age, sex, hospitalization time, and mortality in both groups. In the LPG-caused burn cases, 41 burns (73.2%) occurred at home, seven (12.5) were work-related mishaps, and eight (14.3) were associated with car accidents. The majority of the LPG burns (82%, 46 patients) resulted from a gas leak, and 18% of them were related to the failure to close LPG tubes in the patients' kitchens (10 patients). Burns to the face and neck (82 vs 67%, P = .039) and upper (62 vs 23%, P = .000) and lower (70 vs 45%, P = .002) extremities were significantly higher in LPG-caused burn cases than flame-burned cases. General awareness regarding the risk of LPG and first aid for burns appears to be lacking. The LPG delivery system should be standardized throughout countries that widely use LPG.

Runout distance and dynamic pressure of pyroclastic density currents: Evidence from 18 May 1980 blast surge of Mount St. Helens

NASA Astrophysics Data System (ADS)

Gardner, J. E.; Andrews, B. J.

2016-12-01

Pyroclastic density currents (flows and surges) are one of the most deadly hazards associated with volcanic eruptions. Understanding what controls how far such currents will travel, and how their dynamic pressure evolves, could help mitigate their hazards. The distance a ground hugging, pyroclastic density current travels is partly limited by when it reverses buoyancy and lifts off into the atmosphere. The 1980 blast surge of Mount St. Helens offers an example of a current seen to lift off. Before lofting, it had traveled up to 20 km and leveled more than 600 km3 of thick forest (the blowdown zone). The outer edge of the devastated area - where burned trees that were left standing (the singe zone) - is where the surge is thought to have lifted off. We recently examined deposits in the outer parts of the blowdown and in the singe zone at 32 sites. The important finding is that the laterally moving surge travelled into the singe zone, and hence the change in tree damage does not mark the run out distance of the ground hugging surge. Eyewitness accounts and impacts on trees and vehicles reveal that the surge consisted of a fast, dilute "overcurrent" and a slower "undercurrent", where most of the mass (and heat) was retained. Reasonable estimates for flow density and velocity show that dynamic pressure of the surge (i.e., its ability to topple trees) peaked near the base of the overcurrent. We propose that when the overcurrent began to lift off, the height of peak dynamic pressure rose above the trees and stopped toppling them. The slower undercurrent continued forward, burning trees but it lacked the dynamic pressure needed to topple them. Grain-size variations argue that it slowed from 30 m/s when it entered the singe zone to 3 m/s at the far end. Buoyancy reversal and liftoff are thus not preserved in the deposits where the surge lofted upwards.

Iron and molecular opacities and the evolution of Population I stars

NASA Technical Reports Server (NTRS)

Stothers, Richard B.; Chin, Chao-Wen

1993-01-01

Effects of recent opacity revisions on the evolution of Population I stars are explored over the range 1.5-60 solar masses. Opacity parameters considered include the angular momentum coupling scheme for iron, the relative iron abundance, the total metal abundance, and diatomic and triatomic molecular sources. Only the total metal abundance exerts an important control over the evolutionary tracks. Blue loops on the H-R diagram during core helium burning can be very sensitive to opacity, but only insofar as the simple formation or suppression of a blue loop is concerned. The blue loops are most robust for stellar masses around 10 solar masses. We confirm, from a comparison of stellar models with observational data, that the total metal abundance is close to solar and that convective core overshooting is likely to be very slight. The new models predict the existence of an iron convection zone in the envelope and a great widening of the main-sequence band in the H-R diagram at luminosities brighter than 100,000 solar luminosities.

Seek a Minor Sun: The Distribution of Habitable Planets in the Hertzsprung-Russell-Rosenberg Diagram

NASA Astrophysics Data System (ADS)

Gaidos, Eric

2015-07-01

The Sun-Earth systems has long been used as a template to understand habitable planets around other stars and to develop missions to seek them. However, two decades of exoplanet studies have shown that many, if not most planetary systems around G dwarf stars do not resemble the Solar System. Moreover, an objective census of our Galaxy might ignore solar- type stars and focus on M dwarfs, which constitute some 80% of all stars in the neighborhood. Recent work has shown that M dwarfs have more close-in planets than solar-type stars, and perhaps more planets in the "habitable zone" defined by stellar irradiation. M dwarfs also burn hydrogen over a vastly longer time; slow evolution on the main sequence means a planet can remain habitable for much longer, providing a more permissive environment for the evo- lution of life and intelligence. If M dwarfs are such compelling locales to look for life, why are we ourselves not orbiting a red Sun?

Biomass burning signals over the South Atlantic Ocean before and during the El Niño event of 2015/16

NASA Astrophysics Data System (ADS)

Arnold, Sabrina G.; Feist, Dietrich G.; Marshall, Julia; Guillermo Nuñez Ramirez, Tonatiuh

2017-04-01

The Max Planck Institute for Biogeochemistry (MPI-BGC) has been operating a Fourier-Transform Spectrometer (FTS) on Ascension Island (8° S, 14° W) as part of the Total Carbon Column Observation Network (TCCON). Since 2012, this instrument has been observing column-averaged dry-air mole fractions (commonly referred to as Xgas) of greenhouse gases like CO2, CH4, CO, N2O and others. Due to its location in the southern trade wind zone, the station is downwind from Africa most of the time. Different parts of the total column above the station are influenced by fluxes from different regions. Especially the lower layers of the free troposphere just above the planetary boundary layer (PBL) show strong biomass burning signals. XCH4 and especially XCO are strongly enhanced during the northern and southern African burning seasons. For XCO, enhancements of 50-100% in the total column can be observed on the time scale of days. Transport model simulations suggest that biomass burning signals from as far as the Eastern Indian Ocean may be detected over Ascension Island. Most of these effects are not visible from observations in the PBL. The 5-year time series allows a first look at the effect of the 2015/16 El Niño on the biomass burning patterns in the Southern Hemisphere.

[Electrical burns in children. 3 years of case histories].

PubMed

Caneira, E; Serafim, Z; Duarte, R; Leal, M J

1996-01-01

The Burn Unit of Dona Estefânia Hospital admitted a total of 454 patients from January 1992 to January 1995, 24 of these patients suffered from electric shock. Of these 24 patients 3 suffered burns in the mouth, 15 in one or both hands and 6 multiple burns. In 19 patients the burns were up to 1%. A description is made of 5 cases, male children between the ages of 9 and 13 years, which were deemed severe. The incidents occurred outdoors with different voltages and in activities considered of ludic or experimental nature: two on the roof of a house, two with railway cables and one with an electrical cable in a port zone. The burnt areas vary between 4% and 70%, all of them 2nd and 3rd degree, with hospitalization lasting from 36 to 116 days. In addition to early and coordinated medical and rehabilitative treatment, according to individual needs, a description is also made of the cutaneous sequelae (deforming cicatrices, bridles), neurologic and psychologic sequelae, with emphasis on a patient who underwent amputation of the lower left leg and 4th and 5th ranges of the right foot. It was concluded that measures should be taken in education and legislation to prevent these accidents. Relevance is given to the need for a multidisciplinary team and specialized center for the treatment of these patients.

Ionization and chemiluminescence during the progressive aeration of methane flames

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weinberg, Felix; Carleton, Fred

Saturation currents and chemiluminescence, especially at the CH{sup *} and C{sub 2}{sup *} wavelengths, are measured for a range of small, laminar methane flames during progressive addition of air, with the principal objective of distinguishing between pure diffusion flames, premixed flames of compositions falling between the upper and lower flammability limits, and the broad range of aerated flames lying in between these regimes. Flame areas defined by the loci of maximum luminosity and by schlieren contours were recorded, so that saturation current densities, CH{sup *} and C{sub 2}{sup *} emission per unit flame area, as well as burning velocities couldmore » be deduced. For admixtures of less than 70 vol.%, air appears to act, surprisingly, as an inert diluent as regards saturation currents, so that saturation currents are essentially proportional to fuel flow alone. Much the same applies to chemiluminescence. However, schlieren contours, which were recorded both to provide a basis for burning velocity measurements and to explore density changes in the reactants, indicated the presence of a burner - stabilised propagating reaction zone ahead of the luminous flame surface starting at around 50 vol.% and possibly even at lower air admixtures. This evidence of a steep change in refractive index is indicative of a premixed reaction zone involving the added oxygen, which however generates no chemi-ionization and emits no light. Even photographing the flame by radiation emitted at the CH{sup *} and C{sub 2}{sup *} wavelengths shows no sign of its existence. Its burning velocity is about 10 cm/s, when stabilized by the surrounding diffusion flame. The most plausible rationale for these observations is the formation of syngas by the partial oxidation of methane. The subsequent burning of CO and H{sub 2} is known to occur without chemi-ionization or appreciable light emission. (author)« less

Apyrase Elicits Host Antimicrobial Responses and Resolves Infection in Burns.

PubMed

Bayliss, Jill M; Levi, Benjamin; Wu, Jianfeng; Wang, Stewart C; Su, Grace L; Xi, Chuanwu

The authors previously reported that adenosine triphosphate (ATP) stimulates biofilm formation and removal of the ATP could reduce biofilm formation. The main objective of this study was to evaluate the effects of the ATP-hydrolyzing enzyme, apyrase, on control of Acinetabacter baumannii infection in the burn wound as well as to assess host skin antimicrobial responses. The authors found that apyrase stimulated nitric oxide formation at the wound site and reduced CD55 expression, thereby inducing the assembly of membrane attack complexes. Apyrase treatment nearly eradicated multidrug-resistant A. baumannii from burn wounds in the absence of antibiotics. Apyrase may be an effective therapy against antibiotic-resistant bacterial infections in burns.

Exposure to bushfire smoke during prescribed burns and wildfires: firefighters' exposure risks and options.

PubMed

Reisen, Fabienne; Hansen, Dane; Meyer, C P Mick

2011-02-01

Firefighters are exposed to known health-damaging air pollutants present in bushfire smoke and poorly managed exposure can result in serious health issues. A better understanding of exposure levels and the major factors influencing exposures is crucial for the development of mitigation strategies to minimise exposure risks and adverse health impacts. This study monitored air toxics within the breathing zone of firefighters at prescribed burns and at wildfires in Australia. The results showed that exposure levels were highly variable, with higher exposures (sometimes exceeding occupational exposure standards) associated with particular work tasks (such as patrol and suppression) and with certain burn conditions. The majority of firefighter's exposures were at low and moderate levels (~60%), however considerable attention should be given to the high (~30%) and very high (6%) exposure risk situations for which acute and chronic health risks are very likely and for which control strategies should be developed and implemented to minimise health risks. Copyright © 2010 Elsevier Ltd. All rights reserved.

The “fire stick farming” hypothesis: Australian Aboriginal foraging strategies, biodiversity, and anthropogenic fire mosaics

PubMed Central

Bliege Bird, R.; Bird, D. W.; Codding, B. F.; Parker, C. H.; Jones, J. H.

2008-01-01

Aboriginal burning in Australia has long been assumed to be a “resource management” strategy, but no quantitative tests of this hypothesis have ever been conducted. We combine ethnographic observations of contemporary Aboriginal hunting and burning with satellite image analysis of anthropogenic and natural landscape structure to demonstrate the processes through which Aboriginal burning shapes arid-zone vegetational diversity. Anthropogenic landscapes contain a greater diversity of successional stages than landscapes under a lightning fire regime, and differences are of scale, not of kind. Landscape scale is directly linked to foraging for small, burrowed prey (monitor lizards), which is a specialty of Aboriginal women. The maintenance of small-scale habitat mosaics increases small-animal hunting productivity. These results have implications for understanding the unique biodiversity of the Australian continent, through time and space. In particular, anthropogenic influences on the habitat structure of paleolandscapes are likely to be spatially localized and linked to less mobile, “broad-spectrum” foraging economies. PMID:18809925

Epidemiology and outcome analysis of scalds in children caused by "guo lian kang": an 11-year review in a burn center in China.

PubMed

Zhu, Liqiang; Zhang, Hong; Shi, Fusheng; Yi, Dong; Zhu, Guangjun

2015-03-01

The objective of this study was to investigate the epidemiological characteristics of scalds induced by "guo lian kang" (literally "stove connected to bed") in children. The demographic, burn features, outcome, and other information of 0-14-year-old children with "guo lian kang"-induced scalds admitted to the burn treatment center of the 322 Hospital of the People's Liberation Army in Datong from 30 September 2001 to 31 December 2011 were analyzed. Among the 1993 children clearly documented with scalds due to hot liquid in vessels, 795 (39.89%) had burns due to "guo lian kang." The proportion of the pediatric burns caused by "guo lian kang" was 55.56% in 2002 and 37.30% in 2011, with a decreasing trend. One-year-old children accounted for the highest proportion of children with burns due to "guo lian kang" (male:female=1.54:1). Scalding mostly occurred from October to May; the most common times were around 8:00 AM, 11:00 AM, and 7:00 PM. Most scalds occurred on the upper limbs, 90.22% of which were dermal burns. The median burn area was 11% of the total body surface area. The burn agent was mainly hot water in pots. Scalding mostly occurred when the children accidentally sat on, or fell or stepped into the pot while playing. Among the children with "guo lian kang"-induced scalds, up to 42.26% of the children did not receive any treatment before hospital admission, and 18.86% of the children were admitted to the hospital ≥6h after the occurrence of burns. In addition, 74.97% of the children's families can afford the medical expenses, while 5.28% abandoned treatment because of financial difficulties. There were no significant differences between children with scalds caused by "guo lian kang" and scalds caused due to other reasons considering the age and sex. Compared to scalds due to other reasons, children with "guo lian kang"-induced scalds had greater burn area and depth, shock incidence, surgery rate, blood transfusion rate, length of hospital stay, and hospitalization costs. Preventive measures against burns should be taken from October to May and mainly during cooking time in order to prevent burns in children less than 3 years of age, especially in 1-year-old boys. The most simple and effective preventive measure is to install a barrier between the pot and bed. The incidence of shock in children may be reduced if parents and primary medical staff undergo training to perform first aid for burns and if there are improvements in the referral system after burns. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

A silver coated dressing reduces the incidence of early burn wound cellulitis and associated costs of inpatient treatment: comparative patient care audits.

PubMed

Fong, J; Wood, F; Fowler, B

2005-08-01

In 2000 and 2002, the Royal Perth Hospital (RPH) Burn Unit, Western Australia, conducted two 'before and after' patient care audits comparing the effectiveness and cost of Silvazine (silver sulphadiazine and chlorhexidine digluconate cream) and Acticoat, a new dressing product for in-patient treatment of early burn wounds. The main outcome variables were: burn wound cellulitis, antibiotic use and cost of treatment. Two patient care audits and a comparative sample were used. The two regimes audited were, 'standard treatment' of twice daily showers or washes with 4% chlorhexidine soap and Silvazine cream as a topical dressing (2000, n=51), compared with the 'new treatment' of daily showers of the burn wound with 4% chlorhexidine soap and the application of an Acticoat dressing (2002, n=19). In 2002, costs were also examined using a sample of matched pairs (n=8) of current and previous patients. The main findings were: when using Acticoat the incidence of infection and antibiotic use fell from 55% (28/51) and 57% (29/51) in 2000 to 10.5% (2/19) and 5.2% (1/19) in 2002. The total costs (excluding antibiotics, staffing and surgery) for those treated with Silvazine were US$ 109,357 and those treated with Acticoat were US$ 78,907, demonstrating a saving of US$ 30,450 with the new treatment. The average length of stay (LOS) in hospital was 17.25 days for the Silvazine group and 12.5 days for the Acticoat group-a difference of 4.75 days. These audits demonstrate that Acticoat results in a reduced incidence of burn wound cellulitis, antibiotic use and overall cost compared to Silvazine in the treatment of early burn wounds.

Influence of regional biomass burning on the highly elevated organic carbon concentrations observed at Gosan, South Korea during a strong Asian dust period.

PubMed

Nguyen, Duc Luong; Kim, Jin Young; Ghim, Young Sung; Shim, Shang-Gyoo

2015-03-01

PM2.5 carbonaceous particles were measured at Gosan, South Korea during 29 March-11 April 2002 which includes a pollution period (30 March-01 April) when the highest concentrations of major anthropogenic species (nss-SO4 (2-), NO3 (-), and NH4 (+)) were observed and a strong Asian dust (AD) period (08-10 April) when the highest concentrations of mainly dust-originated trace elements (Al, Ca, Mg, and Fe) were seen. The concentrations of elemental carbon (EC) measured in the pollution period were higher than those measured in the strong AD period, whereas an inverse variation in the concentrations of organic carbon (OC) was observed. Based on the OC/EC ratios, the possible source that mainly contributed to the highly elevated OC concentrations measured in the strong AD period was biomass burning. The influence of the long-range transport of smoke plumes emitted from regional biomass burning sources was evaluated by using MODIS (Moderate Resolution Imaging Spectroradiometer) satellite data for fire locations and the potential source contribution function analysis. The most potential source regions of biomass burning were the Primorsky and Amur regions in Far Eastern Russia and southeastern and southwestern Siberia, Russia. Further discussion on the source characteristics suggested that the high OC concentrations measured in the strong AD period were significantly affected by the smoldering phase of biomass burning. In addition to biomass burning, secondary OC (SOC) formed during atmospheric long-range transport should be also considered as an important source of OC concentration measured at Gosan. Although this study dealt with the episodic case of the concurrent increase of dust and biomass burning particles, understanding the characteristics of heterogeneous mixing aerosol is essential in assessing the radiative forcing of aerosol.

Comparison Between Civilian Burns and Combat Burns From Operation Iraqi Freedom and Operation Enduring Freedom

PubMed Central

Wolf, Steven E.; Kauvar, David S.; Wade, Charles E.; Cancio, Leopoldo C.; Renz, Evan P.; Horvath, Edward E.; White, Christopher E.; Park, Myung S.; Wanek, Sandra; Albrecht, Michael A.; Blackbourne, Lorne H.; Barillo, David J.; Holcomb, John B.

2006-01-01

Objective: To assess outcome differences between locally burned civilians and military personnel burned in a distant combat zone treated in the same facility. Summary Background Data: The United States Army Institute of Surgical Research (USAISR) Burn Center serves as a referral center for civilians and is the sole center for significant burns in military personnel. We made the hypothesis that outcomes for military personnel burned in the current conflict in Iraq and Afghanistan would be poorer because of delays to definitive treatment, other associated injury, and distance of evacuation. Methods: We reviewed the civilian and military records of patients treated at the USAISR from the outset of hostilities in Iraq in April 2003 to May 2005. Demographics, injury data, mortality, and clinical outcomes were compared. Results: We cared for 751 patients during this time period, 273 of whom were military (36%). Military injuries occurred in a younger population (41 ± 19 vs. 26 ± 7 years for civilian and military respectively, P < 0.0001) with a longer time from injury to burn center arrival (1 ± 5 days vs. 6 ± 5, P < 0.0001), a higher Injury Severity Score (ISS 5 ± 8 vs. 9 ± 11, P < 0.0001), and a higher incidence of inhalation injury (8% vs. 13%, P = 0.024). Total burn size did not differ. Mortality was 7.1% in the civilian and 3.8% in the military group (P = 0.076). When civilians outside the age range of the military cohort were excluded, civilian mortality was 5.0%, which did not differ from the military group (P = 0.57). Total body surface area (TBSA) burned, age ≥40 years, presence of inhalation injury, and ventilator days were found to be important predictors of mortality by stepwise regression, and were used in a final predictive model with the area under receiver operator characteristic curve of 0.97 for both populations considered together. No significant effect of either group was identified during development. Conclusions: Mortality does not differ between civilians evacuated locally and military personnel injured in distant austere environments treated at the same center. PMID:16772782

Comparison between civilian burns and combat burns from Operation Iraqi Freedom and Operation Enduring Freedom.

PubMed

Wolf, Steven E; Kauvar, David S; Wade, Charles E; Cancio, Leopoldo C; Renz, Evan P; Horvath, Edward E; White, Christopher E; Park, Myung S; Wanek, Sandra; Albrecht, Michael A; Blackbourne, Lorne H; Barillo, David J; Holcomb, John B

2006-06-01

To assess outcome differences between locally burned civilians and military personnel burned in a distant combat zone treated in the same facility. The United States Army Institute of Surgical Research (USAISR) Burn Center serves as a referral center for civilians and is the sole center for significant burns in military personnel. We made the hypothesis that outcomes for military personnel burned in the current conflict in Iraq and Afghanistan would be poorer because of delays to definitive treatment, other associated injury, and distance of evacuation. We reviewed the civilian and military records of patients treated at the USAISR from the outset of hostilities in Iraq in April 2003 to May 2005. Demographics, injury data, mortality, and clinical outcomes were compared. : We cared for 751 patients during this time period, 273 of whom were military (36%). Military injuries occurred in a younger population (41 +/- 19 vs. 26 +/- 7 years for civilian and military respectively, P < 0.0001) with a longer time from injury to burn center arrival (1 +/- 5 days vs. 6 +/- 5, P < 0.0001), a higher Injury Severity Score (ISS 5 +/- 8 vs. 9 +/- 11, P < 0.0001), and a higher incidence of inhalation injury (8% vs. 13%, P = 0.024). Total burn size did not differ. Mortality was 7.1% in the civilian and 3.8% in the military group (P = 0.076). When civilians outside the age range of the military cohort were excluded, civilian mortality was 5.0%, which did not differ from the military group (P = 0.57). Total body surface area (TBSA) burned, age > or =40 years, presence of inhalation injury, and ventilator days were found to be important predictors of mortality by stepwise regression, and were used in a final predictive model with the area under receiver operator characteristic curve of 0.97 for both populations considered together. No significant effect of either group was identified during development. Mortality does not differ between civilians evacuated locally and military personnel injured in distant austere environments treated at the same center.

Influence of logging on the effects of wildfire in Siberia

NASA Astrophysics Data System (ADS)

Kukavskaya, E. A.; Buryak, L. V.; Ivanova, G. A.; Conard, S. G.; Kalenskaya, O. P.; Zhila, S. V.; McRae, D. J.

2013-12-01

The Russian boreal zone supports a huge terrestrial carbon pool. Moreover, it is a tremendous reservoir of wood products concentrated mainly in Siberia. The main natural disturbance in these forests is wildfire, which modifies the carbon budget and has potentially important climate feedbacks. In addition, both legal and illegal logging increase landscape complexity and affect burning conditions and fuel consumption. We investigated 100 individual sites with different histories of logging and fire on a total of 23 study areas in three different regions of Siberia to evaluate the impacts of fire and logging on fuel loads, carbon emissions, and tree regeneration in pine and larch forests. We found large variations of fire and logging effects among regions depending on growing conditions and type of logging activity. Logged areas in the Angara region had the highest surface and ground fuel loads (up to 135 t ha-1), mainly due to logging debris. This resulted in high carbon emissions where fires occurred on logged sites (up to 41 tC ha-1). The Shushenskoe/Minusinsk and Zabaikal regions are characterized by better slash removal and a smaller amount of carbon emitted to the atmosphere during fires. Illegal logging, which is widespread in the Zabaikal region, resulted in an increase in fire hazard and higher carbon emissions than legal logging. The highest fuel loads (on average 108 t ha-1) and carbon emissions (18-28 tC ha-1) in the Zabaikal region are on repeatedly burned unlogged sites where trees fell on the ground following the first fire event. Partial logging in the Shushenskoe/Minusinsk region has insufficient impact on stand density, tree mortality, and other forest conditions to substantially increase fire hazard or affect carbon stocks. Repeated fires on logged sites resulted in insufficient tree regeneration and transformation of forest to grasslands. We conclude that negative impacts of fire and logging on air quality, the carbon cycle, and ecosystem sustainability could be decreased by better slash removal in the Angara region, removal of trees killed by fire in the Zabaikal region, and tree planting after fires in drier conditions where natural regeneration is hampered by soil overheating and grass proliferation.

Siberian and North American Biomass Burning Contributions to the Processes that Influenced the 2008 Arctic Aircraft and Satellite Field Campaigns

NASA Astrophysics Data System (ADS)

Soja, A. J.; Stocks, B. J.; Carr, R.; Pierce, R. B.; Natarajan, M.; Fromm, M.

2009-05-01

Current climate change scenarios predict increases in biomass burning in terms of increases in fire frequency, area burned, fire season length and fire season severity, particularly in boreal regions. Climate and weather control fire danger, which strongly influences the severity of fire events, and these in turn, feed back to the climate system through direct and indirect emissions, modifying cloud condensation nuclei and altering albedo (affecting the energy balance) through vegetative land cover change and deposition. Additionally, fire emissions adversely influence air quality and human health downwind of burning. The boreal zone is significant because this region stores the largest reservoir of terrestrial carbon, globally, and will experience climate change impacts earliest. Boreal biomass burning is an integral component to several of the primary goals of the ARCTAS (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites) and ARCPAC (Aerosol, Radiation, and Cloud Processes affecting Arctic Climate) 2008 field campaigns, which include its implication for atmospheric composition and climate, aerosol radiative forcing, and chemical processes with a focus on ozone and aerosols. Both the spring and summer phases of ARCTAS and ARCPAC offered substantial opportunities for sampling fresh and aged biomass burning emissions. However, the extent to which spring biomass burning influenced arctic haze was unexpected, which could inform our knowledge of the formation of arctic haze and the early deposition of black carbon on the icy arctic surface. There is already evidence of increased extreme fire seasons that correlate with warming across the circumboreal zone. In this presentation, we discuss seasonal and annual fire activity and anomalies that relate to the ARCTAS and ARCPAC spring (April 1 - 20) and summer (June 18 - July 13) periods across Siberia and North America, with particular emphasis on fire danger and fire behavior as they relate to smoke emissions. Fire severity and subsequent emission levels are directly related to fire danger conditions, which reflect and incorporate both antecedent and current weather. In this century, it is predicted that fire regime increases will be the catalyst for ecosystem change, which will force ecosystems to move more rapidly towards a new equilibrium with climate. However, the reasons for ecosystem change are often accompanied by social and political drivers of land cover change, which complicate the relationship between fire and weather. For instance, since the collapse of the former Soviet Union, financial support for fire fighting is minimal, communal agricultural lands have been abandoned and a number of species are no longer protected (e.g. Saiga in Kalmykia), and each of these factors strongly influences vegetation cover and fire regimes, leading to a complicated interaction of processes that control fire and its affect on the larger environment.

Macro-Scale Reactive Flow Model for High-Explosive Detonation in Support of ASCI Weapon Safety Milepost

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reaugh, J E

2002-01-03

Explosive grain-scale simulations are not practical for weapon safety simulations. Indeed for nearly ideal explosives with reaction zones of order 500 {micro}m, even reactive flow models are not practical for weapon safety simulations. By design, reactive flow models must resolve the reaction zone, which implies computational cells with dimension of order 50 {micro}m for such explosives. The desired result for a simulation in which the reaction zone is not resolved is that the explosive behaves as an ideal one. The pressure at the shock front rises to the Chapman-Jouget (CJ) pressure with a reaction zone dimension that is like thatmore » of a shock propagating in an unreactive medium, on the order of a few computational cells. It should propagate with the detonation velocity that is determined by the equation of state of the products. In the past, this was achieved in one dimensional simulations with ''beta-burn'', a method in which the extent of conversion to final product is proportional to the approach of the specific volume in the shock front to the specific volume of the CJ state. One drawback with this method is that there is a relatively long build-up to steady detonation that is typically 50 to 100 computational cells. The need for relatively coarsely zoned simulations in two dimensions lead to ''program-burn'' by which the time to detonation can be determined by a simple ray-tracing algorithm when there are no barriers or shadows. Complications arise in two and three dimensions to the extent that some calculations of the lighting time in complex geometry can give incorrect results. We sought to develop a model based on reactive flow that might help the needs of the Weapon Safety Simulation milepost. Important features of the model are: (1) That it be useable with any equation of state description of the explosive product gases including both JWL and LEOS table forms. (2) That it exhibits the desired dependence on zone size. We believe that the model described here does exhibit these features.« less

Investigations of ash fouling with cattle wastes as reburn fuel in a small-scale boiler burner under transient conditions.

PubMed

Oh, Hyukjin; Annamalai, Kalyan; Sweeten, John M

2008-04-01

Fouling behavior under reburn conditions was investigated with cattle wastes (termed as feedlot biomass [FB]) and coal as reburn fuels under a transient condition and short-time operation. A small-scale (30 kW or 100,000 Btu/hr) boiler burner research facility was used for the reburn experiments. The fuels considered for these experiments were natural gas (NG) for the ashless case, pure coal, pure FB, and blends of coal and FB. Two parameters that were used to characterize the ash "fouling" were (1) the overall heat-transfer coefficient (OHTC) when burning NG and solid fuels as reburn fuels, and (2) the combustible loss through ash deposited on the surfaces of heat exchanger tubes and the bottom ash in the ash port. A new methodology is presented for determining ash-fouling behavior under transient conditions. Results on the OHTCs for solid reburn fuels are compared with the OHTCs for NG. It was found that the growth of the layer of ash depositions over longer periods typically lowers OHTC, and the increased concentration of ash in gas phase promotes radiation in high-temperature zones during initial periods while decreasing the heat transfer in low-temperature zones. The ash analyses indicated that the bottom ash in the ash port contained a smaller percentage of combustibles with a higher FB percentage in the fuels, indicating better performance compared with coal because small particles in FB burn faster and the FB has higher volatile matter on a dry ash-free basis promoting more burn out.

[Timing of bacterial colonization in severe burns: is strict isolation necessary?].

PubMed

Barret, Juan P

2003-12-01

Infection is still one of the main causes of mortality in severe burn patients. Strict isolation has been used for the prevention of infection, but the efficacy of this measure is debatable. The aim of this study was to determine the timing of bacterial colonization in these patients and to ascertain whether strict isolation is indicated. Thirty consecutive children with severe burns were studied. Patients were only barrier-nursed during dressing changes. On admission and twice weekly over the entire hospital stay, burn, sputum, gastric aspirates, feces, and blood samples were obtained for culture. All isolates were tested for specific biotypes. Results were studied with linear regression and repeated measures ANOVA to determine the timing of colonization and cross-colonization between patients. On admission, normal cutaneous flora were isolated from burn cultures of all patients. The remaining cultures were negative. After one week, gastric aspirates were found to be colonized by gram-negative bacteria and fungi. This was followed by colonization of feces, burn, and sputum cultures. Biotype identification showed unidirectional colonization from the gastrointestinal tract to burns and upper airway. There were no cross infections between patients. Microbial colonization in severe burn patients was endogenous in nature and there were no cross infections. Thus, strict isolation is not necessary in burn centers, except during outbreaks of multi-resistant microorganisms.

Health-related quality of life in Swedish pediatric burn patients and associations with burn and family characteristics.

PubMed

Sveen, J; Sjöberg, F; Öster, C

2014-08-01

Although many children with burns recover well and have a satisfying quality of life after the burn, some children do not adjust as well. Health-related quality of life (HRQoL) focuses on the impact health status has on quality of life. The aim of this study was to assess HRQoL with the American Burn Association/Shriners Hospitals for Children Burn Outcomes Questionnaire (BOQ) in a nationwide Swedish sample of children with burns 0.3-9.0 years after injury. Participants were parents (n=109) of children aged up to 18 years at the time of investigation who were treated at the Linköping or Uppsala Burn Center between 2000 and 2008. The majority of children did not have limitations in physical function and they did not seem to experience much pain. However, there were indications of psychosocial problems. Parents of preschool children reported most problems with the children's behavior and family disruption, whereas parents of children aged 5-18 years reported most problems with appearance and emotional health. There were mainly burn-related variables associated with suboptimal HRQoL in children aged 5-18 years, while family-related variables did not contribute as much. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

Microbiology and antibiotic resistance in severe burns patients: A 5 year review in an adult burns unit.

PubMed

Bahemia, I A; Muganza, A; Moore, R; Sahid, F; Menezes, C N

2015-11-01

Infections are a major problem in burns patients. Knowledge of the incidence and antimicrobial sensitivities of the microorganisms commonly encountered within each institution's burns unit is important as it informs and directs empiric antibiotic therapy. This was a retrospective review of patients admitted from 1 January 2008 to 31 December 2012 to an adult burns intensive care unit. Specimens chosen for analysis were wound swabs, blood cultures, venous catheter tips, tracheal aspirates, sputum, urine and wound tissue. Records were accessed from the admission register and laboratory information system to obtain the relevant data. During the study period, 352 patients were admitted to the adult burns intensive care unit, of which, 341 patients were included. The mortality rate was 44.6%. Flame burns were the commonest. Mortality rate amongst patients with bacteremia was 46.9%. Acinetobacter baumannii, Pseudomonas aeruginosa and methicillin resistant Staphylococcus aureus (MRSA) were found to be the most common organisms cultured in most specimens. The main three organisms identified in specimen cultures in our adult burns intensive care unit were A. baumannii, P. aeruginosa and MRSA. This study has helped establish a better empiric approach to the management of our septic burns patients. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

Regional paleofire regimes affected by non-uniform climate, vegetation and human drivers

NASA Astrophysics Data System (ADS)

Blarquez, Olivier; Ali, Adam A.; Girardin, Martin P.; Grondin, Pierre; Fréchette, Bianca; Bergeron, Yves; Hély, Christelle

2015-09-01

Climate, vegetation and humans act on biomass burning at different spatial and temporal scales. In this study, we used a dense network of sedimentary charcoal records from eastern Canada to reconstruct regional biomass burning history over the last 7000 years at the scale of four potential vegetation types: open coniferous forest/tundra, boreal coniferous forest, boreal mixedwood forest and temperate forest. The biomass burning trajectories were compared with regional climate trends reconstructed from general circulation models, tree biomass reconstructed from pollen series, and human population densities. We found that non-uniform climate, vegetation and human drivers acted on regional biomass burning history. In the open coniferous forest/tundra and dense coniferous forest, the regional biomass burning was primarily shaped by gradual establishment of less climate-conducive burning conditions over 5000 years. In the mixed boreal forest an increasing relative proportion of flammable conifers in landscapes since 2000 BP contributed to maintaining biomass burning constant despite climatic conditions less favourable to fires. In the temperate forest, biomass burning was uncoupled with climatic conditions and the main driver was seemingly vegetation until European colonization, i.e. 300 BP. Tree biomass and thus fuel accumulation modulated fire activity, an indication that biomass burning is fuel-dependent and notably upon long-term co-dominance shifts between conifers and broadleaf trees.

INFLUENCE OF INHALATION INJURY ON ENERGY EXPENDITURE IN SEVERELY BURNED CHILDREN

PubMed Central

Przkora, Rene; Fram, Ricki Y.; Herndon, David N.; Suman, Oscar E.; Mlcak, Ronald P.

2014-01-01

Objective Determine the effect of inhalation injury on burn-induced hypermetabolism in children. Design Prospective study comparing hypermetabolism (i.e., resting energy expenditure and oxygen consumption) in burned children with and without inhalation injury during acute hospitalization. Setting Single pediatric burn center. Patients Eighty-six children (1–18 years) with ≥ 40% total body surface area burns were stratified to two groups: no inhalation injury and inhalation injury. Interventions None. Main Measurements and Results Inhalation injury was diagnosed based on bronchoscopic evaluation. At admission, PaO2:FiO2 ratios (an index of respiratory distress) were significantly higher in patients with no inhalation injury than in patient with inhalation injury. No differences were detected in resting energy expenditure or percent of the predicted basal metabolic rate between groups. Additionally, oxygen consumption did not significantly differ between groups. Conclusions Inhalation injury does not augment the burn-induced hypermetabolic stress response in children, as reflected by resting energy expenditure and oxygen consumption. PMID:24893760

Filling Gaps in Biogeochemical Understanding of Wildfire Effects on Watersheds and Water Quality

NASA Astrophysics Data System (ADS)

Rhoades, Charles; Covino, Timothy; Chow, Alex

2017-04-01

Large, high-severity wildfires alter the biogeochemical conditions that determine how watersheds retain and release nutrients and influence stream water quality. These effects are commonly expected to abate within a few years, but recent studies show that post-fire watershed changes can have persistent, but poorly-understood biogeochemical consequences. Owing to the increased frequency and extent of high-severity wildfires predicted for western North America, and the growing awareness of the links between wildfire and clean water supply, there is a need to address these knowledge gaps. For the past 15 years we have tracked stream nutrients, chemistry, temperature, and sediment after the 2002 Hayman Fire, the largest wildfire in Colorado history. Our earlier work showed that headwater catchments that experienced extensive, high-severity forest fires had elevated stream nitrate, temperature, and turbidity for five post-fire years. Recent sampling, conducted 13 and 14 years after the fire, found that turbidity had largely returned to pretreatment levels, but that stream nitrate remained an order of magnitude above pre-fire levels in catchments with extensive high-severity wildfire. Stream temperature and total dissolved nitrogen concentration also remained higher in those catchments compared to unburned streams. Decreased plant demand is the mechanism commonly credited for post-fire nutrient losses, though our current work is evaluating the implications of soil and stream nutrient uptake and supply on persistent nitrogen (N) export from severely-burned catchments. For example, we have measured higher total soil N and higher net N mineralization in severely-burned portions of the Hayman Fire compared to moderately or unburned areas, indicating that higher soil N supply may contribute to N losses from upland soils. Conversely, using a nutrient tracer approach we found reduced N uptake in burned streams, which suggests a switch from the N-limited conditions typical of pristine catchments. Low stream dissolved organic carbon (DOC) in severely-burned catchments suggests greater carbon limitation on in-stream biological activity. This is the likely result of organic matter losses during the wildfire compounded by low allochthonous inputs from uplands or riparian zones. We also find that catchments with severely-burned headwater reaches and sparse riparian vegetation have high stream nitrate. Our findings regarding soil N supply and in-stream N retention coupled with the persistent N losses from burned headwaters and exposed riparian zones help prioritize restoration efforts aimed at mitigating long-term water quality effects of severe wildfires.

Multiresource effects of a stand-replacement prescribed fire in the Pinus contorta-Abies lasiocarpa vegetation zone of central Washington.

Treesearch

Arthur R. Tiedemann; Paul M. Woodard

2002-01-01

A stand-replacement prescribed fire in an over-mature lodgepole pine (Pinus contorta Dougl. ex Loud.)-subalpine fir (Abies lasiocarpa (Hook.) Nutt.) stand (snag area) and in a mature lodgepole pine thicket (thicket area) resulted in lower plant diversity within the first year after burning, and as fire energy outputs increased...

Seed Biology and Technology of Quercus

Treesearch

F.T. Bonner; John A. Vozzo

1987-01-01

The genus Quercus,known as oak, includes worldwide some 500 species with 58 of these species in the United States, making it this country's largest genus of native trees (Little 1979). Oak is therefore an important group of temperate-zone forest trees. In addition, oaks are significant components of many of the major forest types of the South (Burns 1983)and are...

Fourmile Canyon: Living with wildfire

Treesearch

Hannah Brenkert-Smith; Patricia A. Champ

2011-01-01

The most devastating wildfire in Colorado's history in terms of property loss began on Labor Day, September 6, 2010. The Fourmile Canyon Fire was located just 5 miles west of downtown Boulder, CO, in a wildland-urban interface (WUI) zone with homes located on steep slopes and in dense ponderosa pine and Douglas-fir forest. The fire, fueled by high winds, burned 6,...

Remote sensing of WUI fuel treatment effectiveness following the 2007 wildfires in central Idaho

Treesearch

Andrew T. Hudak; Theresa B. Jain; Penelope Morgan; Jess T. Clark

2011-01-01

The 2007 East Zone and Cascade wildfires in central Idaho burned through fuel treatments in the wildland-urban interface (WUI) surrounding two local communities: Secesh Meadows and Warm Lake. The WUI fuel treatments funded by the National Fire Plan were designed to increase fire fighter safety, protect people and property, and mitigate severe fire effects on natural...

Fire emissions in central Siberia

Treesearch

Douglas J. McRae; Steve P. Baker; Yuri N. Samsonov; Galina A. Ivanova

2009-01-01

Wildfires in the Russian boreal forest zone are estimated to typically burn 12-14 million hectares (ha) annually [Cahoon et al. 1994; Conard and Ivanova 1997; Conard et al. 2002; Dixon and Krankina 1993; Kasischke et al. 1999]. Boreal forests contain about 21 percent of global forest area and 28 percent of global forest carbon [Dixon et al. 1994], yet data on the...

Detonation Velocity Calculations of Explosives with Slowly-Burning Constituents

NASA Astrophysics Data System (ADS)

Howard, W. Michael; Souers, P. Clark; Fried, Laurence E.

1997-07-01

The thermochemical code Equilbrium CHEETAH has been modified to allow partial reaction of constituents and partial flow of heat. Solid or liquid reactants are described by Einstein oscillators, whose temperatures can be changed to allow heat transfer. Hydroxy-terminated-poly-budadiene, mixed with RDX or HMX, does not react, as shown by the effect on the calculated detonation velocity. Aluminum and ammonium perchlorate in composites also do not react. Only partial heat flow also takes place in the unreacted materials. These results show that the usual assumption of total burn in a thermochemical code is probably incorrect, at least in the sonic reaction zone that drives the detonation velocity. A kinetic code would be the logical extension of this work.

Satellite Analysis of the Severe 1987 Forest Fires in Northern China and Southeastern Siberia

NASA Technical Reports Server (NTRS)

Cahoon, Donald R., Jr.; Stocks, Brian J.; Levine, Joel S.; Cofer, Wesley R., III; Pierson, Joseph M.

1994-01-01

Meteorological conditions, extremely conducive to fire development and spread in the spring of 1987, resulted in forest fires burning over extremely large areas in the boreal forest zone in northeastern China and the southeastern region of Siberia. The great China fire, one of the largest and most destructive forest fires in recent history, occurred during this period in the Heilongjiang Province of China. Satellite imagery is used to examine the development and areal distribution of 1987 forest fires in this region. Overall trace gas emissions to the atmosphere from these fires are determined using a satellite-derived estimate of area burned in combination with fuel consumption figures and carbon emission ratios for boreal forest fires.

Satellite analysis of the severe 1987 forest fires in northern China and southeastern Siberia

NASA Technical Reports Server (NTRS)

Cahoon, Donald R, Jr.; Stocks, Brian J.; Levine, Joel S.; Cofer, Wesley R., III; Pierson, Joseph M.

1994-01-01

Meteorological conditions, extremely conducive to fire development and spread in the spring of 1987, resulted in forest fires burning over extremely large areas in the boreal forest zone in northeastern China and the southeastern region of Siberia. The great China fire, one of the largest and most destructive forest fires in recent history, occurred during this period in the Heilongjiang Province of China. Satellite imagery is used to examine the development and areal distribution of 1987 forest fires in this region. Overall trace gas emissions to the atmosphere from these fires are determined using a satellite-derived estimate of area burned in combination with fuel consumption figures and carbon emission ratios for boreal forest fires.

Burn injuries related to motorcycle exhaust pipes: a study in Greece.

PubMed

Matzavakis, Ioannis; Frangakis, Constantine E; Charalampopoulou, Ava; Petridou, Eleni

2005-05-01

To identify measures that should reduce the incidence of burn injuries resulting from motorcycle exhaust pipes through epidemiological analysis of such injuries. During a 5-year period, 251 persons who suffered burn injuries related to motorcycle exhaust pipes have contacted four major hospitals belonging to the Emergency Department Injury Surveillance System (EDISS) operating since 1996 in Greece. These burn injuries were studied in relation to person, environment and vehicle characteristics. The estimated countrywide incidence of burns from motorcycle exhaust pipes was 17 per 100,000 person-years (208 per 100,000 motorcycle-years). The incidence was two times higher for children than for older persons and among the latter it was 60% higher among females than among males. Most of burn injuries (70.5%) concerned motorcycle passengers, mainly when getting on or off motorcycle, with peak incidence during summer. The most frequent location of burn wounds was below the knee and particularly the right leg. It was estimated that the risk of motorcycle exhaust pipe burns when wearing shorts could be reduced by 46% through wearing long pants. Among the victims 65.3% experienced second degree burns. Motorcycle exhaust burns could be substantially reduced by systematically wearing long pants, by incorporating in the design of motorcycles external thermo resistant shields with adequate distance to the exhaust pipe, and by avoiding riding with children on motorcycles.

A qualitative exploration of psychosocial specialists' experiences of providing support in UK burn care services.

PubMed

Guest, Ella; Griffiths, Catrin; Harcourt, Diana

2018-01-01

A burn can have a significant and long-lasting psychosocial impact on a patient and their family. The National Burn Care Standards (2013) recommend psychosocial support should be available in all UK burn services; however, little is known about how it is provided. The current study aimed to explore experiences of psychosocial specialists working in UK burn care, with a focus on the challenges they experience in their role. Semi-structured telephone interviews with eight psychosocial specialists (two psychotherapists and six clinical psychologists) who worked within UK burn care explored their experiences of providing support to patients and their families. Thematic analysis revealed two main themes: burn service-related experiences and challenges reflected health professionals having little time and resources to support all patients; reduced patient attendance due to them living large distances from service; psychosocial appointments being prioritised below wound-related treatments; and difficulties detecting patient needs with current outcome measures. Therapy-related experiences and challenges outlined the sociocultural and familial factors affecting engagement with support, difficulties treating patients with pre-existing mental health conditions within the burn service and individual differences in the stage at which patients are amenable to support. Findings provide an insight into the experiences of psychosocial specialists working in UK burn care and suggest a number of ways in which psychosocial provision in the NHS burn service could be developed.

β-adrenergic blockade does not impair the skin blood flow sensitivity to local heating in burned and non-burned skin under neutral and hot environments in children

PubMed Central

Rivas, Eric; McEntire, Serina J.; Herndon, David N.; Mlcak, Ronald P.; Suman, Oscar E.

2017-01-01

Objective Tested the hypothesis that propranolol, a drug given to burn patients to reduce hypermetabolism/cardiac stress, may inhibit heat dissipation by changing the sensitivity of skin blood flow (SkBF) to local heating under neutral and hot conditions. Methods In a randomized double-blind study, a placebo was given to 8 burned children while propranolol was given to 13 burned children with similar characteristics (mean ± SD: 11.9±3y, 147±20cm, 45±23kg, 56±12% TBSA). Non-burned children (n=13, 11.4±3y, 152±15cm, 52±13kg) served as healthy controls. A progressive local heating protocol characterized SkBF responses in burned and unburned skin and non-burned control skin under the two environmental conditions (23°C and 34°C) via laser-Doppler flowmetry. Results Resting SkBF was greater in burned and unburned skin compared to the non-burned control (main effect: skin, P<0.0001; 57±32 burned; 38±36 unburned vs 9±8 control %SkBFmax). No difference was found for maximal SkBF capacity to local heating between groups. Additionally, dose response curves for the sensitivity of SkBF to local heating were not different among burned or unburned skin, and non-burned control skin (EC50, P>0.05) under either condition. Conclusion Therapeutic propranolol does not negatively affect SkBF under neutral or hot environmental conditions and further compromise temperature regulation in burned children. PMID:28071840

33 CFR 165.103 - Safety and Security Zones; LPG Vessel Transits in Portland, Maine, Captain of the Port Zone...

Code of Federal Regulations, 2013 CFR

2013-07-01

... Harbor, Portsmouth, New Hampshire. (a) Location. The following areas are safety and security zones: (1... receiving facility on the Piscataqua River, Newington, New Hampshire. (b) Definitions. For purposes of this... Vessel Transits in Portland, Maine, Captain of the Port Zone, Portsmouth Harbor, Portsmouth, New...

33 CFR 165.103 - Safety and Security Zones; LPG Vessel Transits in Portland, Maine, Captain of the Port Zone...

Code of Federal Regulations, 2014 CFR

2014-07-01

... Harbor, Portsmouth, New Hampshire. (a) Location. The following areas are safety and security zones: (1... receiving facility on the Piscataqua River, Newington, New Hampshire. (b) Definitions. For purposes of this... Vessel Transits in Portland, Maine, Captain of the Port Zone, Portsmouth Harbor, Portsmouth, New...

33 CFR 165.103 - Safety and Security Zones; LPG Vessel Transits in Portland, Maine, Captain of the Port Zone...

Code of Federal Regulations, 2012 CFR

2012-07-01

... Harbor, Portsmouth, New Hampshire. (a) Location. The following areas are safety and security zones: (1... receiving facility on the Piscataqua River, Newington, New Hampshire. (b) Definitions. For purposes of this... Vessel Transits in Portland, Maine, Captain of the Port Zone, Portsmouth Harbor, Portsmouth, New...

33 CFR 165.103 - Safety and Security Zones; LPG Vessel Transits in Portland, Maine, Captain of the Port Zone...

Code of Federal Regulations, 2010 CFR

2010-07-01

... Harbor, Portsmouth, New Hampshire. (a) Location. The following areas are safety and security zones: (1... receiving facility on the Piscataqua River, Newington, New Hampshire. (b) Definitions. For purposes of this... Vessel Transits in Portland, Maine, Captain of the Port Zone, Portsmouth Harbor, Portsmouth, New...

33 CFR 165.103 - Safety and Security Zones; LPG Vessel Transits in Portland, Maine, Captain of the Port Zone...

Code of Federal Regulations, 2011 CFR

2011-07-01

... Harbor, Portsmouth, New Hampshire. (a) Location. The following areas are safety and security zones: (1... receiving facility on the Piscataqua River, Newington, New Hampshire. (b) Definitions. For purposes of this... Vessel Transits in Portland, Maine, Captain of the Port Zone, Portsmouth Harbor, Portsmouth, New...

Five-year epidemiology of liquefied petroleum gas-related burns.

PubMed

Jin, Ronghua; Wu, Pan; Ho, Jon Kee; Wang, Xingang; Han, Chunmao

2018-02-01

The incidence of liquefied petroleum gas (LPG)-related burns has increased over recent years, and it has become a serious public health issue in developing countries such as India and Turkey. This paper aims to investigate the epidemiological characteristics of LPG-related burns to provide assistance and suggestions for planning prevention strategies. A 5-year retrospective study was conducted in patients with LPG-related burns admitted to the Department of Burns & Wound Care Center, Second Affiliated Hospital of Zhejiang University, College of Medicine, between 1st January 2011 and 31st December 2015. Information obtained for each patient included age, gender, education status, occupation, medical insurance, average hospital cost, length of hospital stay, monthly distribution of incidence, place of burns, mechanism of burns, extent of burns, site of burns, accompanying injuries, and treatment outcomes. For the first 4 years (2011-2014), the yearly incidence of LPG-related burns was at approximately 10% of all burns; however, in the fifth year (2015) alone, there was a surge to 26.94%. A total of 1337 burn patients were admitted during this period. Of these, 195 patients were admitted because of 169 LPG-related accidents; there were 11 accidents involving more than one victim. LPG-related burns occurred most frequently in patients aged 21-60 years (73.85%). The majority of injuries occurred from May to August (56.41%), and the most common place was home (83.08%, 162 patients). Gas leak (81.03%) was the main cause of LPG-related burns, followed by inappropriate operation (7.69%) and cooking negligence (2.05%). The mean burn area was 31.32±25.40% of TBSA. The most common sites of burns were the upper extremities (37.47%), followed by the head/face and neck (24.80%) and lower extremities (19.95%). The most common accompanying injuries included inhalation injury (23.59%), shock (8.71%), and external injury (7.18%). The average hospital stay was 22.90±19.47days (range 2-84 days). Only 48 patients (24.62%) had medical insurance, while 124 patients (63.59%) had no medical insurance. The average hospital cost of the no medical insurance group was significantly higher (p<0.0001) than that of the medical insurance group. In addition, 72.73% of patients who left against medical advice (LAMA) were uninsured. The number of patients who recovered at our hospital was 165 (84.62%), while 22 patients (11.28%) LAMA. The overall mortality rate was 4.10% (8 patients). Our study shows that the exponential increase in LPG-related burns is alarming. This calls for rigorous precautions. Because gas leak was the main cause of LPG-related burns, any part of LPG stove system that shows signs of weathering should be replaced regularly. In addition, we also found that most of the LAMA patients were uninsured. Thus, comprehensive medical insurance should be involved early in the recovery process to assure a safe and adequate discharge. Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.

Wildfire risk for main vegetation units in a biodiversity hotspot: modeling approach in New Caledonia, South Pacific.

PubMed

Gomez, Céline; Mangeas, Morgan; Curt, Thomas; Ibanez, Thomas; Munzinger, Jérôme; Dumas, Pascal; Jérémy, André; Despinoy, Marc; Hély, Christelle

2015-01-01

Wildfire has been recognized as one of the most ubiquitous disturbance agents to impact on natural environments. In this study, our main objective was to propose a modeling approach to investigate the potential impact of wildfire on biodiversity. The method is illustrated with an application example in New Caledonia where conservation and sustainable biodiversity management represent an important challenge. Firstly, a biodiversity loss index, including the diversity and the vulnerability indexes, was calculated for every vegetation unit in New Caledonia and mapped according to its distribution over the New Caledonian mainland. Then, based on spatially explicit fire behavior simulations (using the FLAMMAP software) and fire ignition probabilities, two original fire risk assessment approaches were proposed: a one-off event model and a multi-event burn probability model. The spatial distribution of fire risk across New Caledonia was similar for both indices with very small localized spots having high risk. The patterns relating to highest risk are all located around the remaining sclerophyll forest fragments and are representing 0.012% of the mainland surface. A small part of maquis and areas adjacent to dense humid forest on ultramafic substrates should also be monitored. Vegetation interfaces between secondary and primary units displayed high risk and should represent priority zones for fire effects mitigation. Low fire ignition probability in anthropogenic-free areas decreases drastically the risk. A one-off event associated risk allowed localizing of the most likely ignition areas with potential for extensive damage. Emergency actions could aim limiting specific fire spread known to have high impact or consist of on targeting high risk areas to limit one-off fire ignitions. Spatially explicit information on burning probability is necessary for setting strategic fire and fuel management planning. Both risk indices provide clues to preserve New Caledonia hot spot of biodiversity facing wildfires.

Wildfire risk for main vegetation units in a biodiversity hotspot: modeling approach in New Caledonia, South Pacific

PubMed Central

Gomez, Céline; Mangeas, Morgan; Curt, Thomas; Ibanez, Thomas; Munzinger, Jérôme; Dumas, Pascal; Jérémy, André; Despinoy, Marc; Hély, Christelle

2015-01-01

Wildfire has been recognized as one of the most ubiquitous disturbance agents to impact on natural environments. In this study, our main objective was to propose a modeling approach to investigate the potential impact of wildfire on biodiversity. The method is illustrated with an application example in New Caledonia where conservation and sustainable biodiversity management represent an important challenge. Firstly, a biodiversity loss index, including the diversity and the vulnerability indexes, was calculated for every vegetation unit in New Caledonia and mapped according to its distribution over the New Caledonian mainland. Then, based on spatially explicit fire behavior simulations (using the FLAMMAP software) and fire ignition probabilities, two original fire risk assessment approaches were proposed: a one-off event model and a multi-event burn probability model. The spatial distribution of fire risk across New Caledonia was similar for both indices with very small localized spots having high risk. The patterns relating to highest risk are all located around the remaining sclerophyll forest fragments and are representing 0.012% of the mainland surface. A small part of maquis and areas adjacent to dense humid forest on ultramafic substrates should also be monitored. Vegetation interfaces between secondary and primary units displayed high risk and should represent priority zones for fire effects mitigation. Low fire ignition probability in anthropogenic-free areas decreases drastically the risk. A one-off event associated risk allowed localizing of the most likely ignition areas with potential for extensive damage. Emergency actions could aim limiting specific fire spread known to have high impact or consist of on targeting high risk areas to limit one-off fire ignitions. Spatially explicit information on burning probability is necessary for setting strategic fire and fuel management planning. Both risk indices provide clues to preserve New Caledonia hot spot of biodiversity facing wildfires. PMID:25691965

System and method for coproduction of activated carbon and steam/electricity

DOEpatents

Srinivasachar, Srivats [Sturbridge, MA; Benson, Steven [Grand Forks, ND; Crocker, Charlene [Newfolden, MN; Mackenzie, Jill [Carmel, IN

2011-07-19

A system and method for producing activated carbon comprising carbonizing a solid carbonaceous material in a carbonization zone of an activated carbon production apparatus (ACPA) to yield a carbonized product and carbonization product gases, the carbonization zone comprising carbonaceous material inlet, char outlet and carbonization gas outlet; activating the carbonized product via activation with steam in an activation zone of the ACPA to yield activated carbon and activation product gases, the activation zone comprising activated carbon outlet, activation gas outlet, and activation steam inlet; and utilizing process gas comprising at least a portion of the carbonization product gases or a combustion product thereof; at least a portion of the activation product gases or a combustion product thereof; or a combination thereof in a solid fuel boiler system that burns a solid fuel boiler feed with air to produce boiler-produced steam and flue gas, the boiler upstream of an air heater within a steam/electricity generation plant, said boiler comprising a combustion zone, a boiler-produced steam outlet and at least one flue gas outlet.

Verification Test of the SURF and SURFplus Models in xRage: Part II

DOE Office of Scientific and Technical Information (OSTI.GOV)

Menikoff, Ralph

2016-06-20

The previous study used an underdriven detonation wave (steady ZND reaction zone profile followed by a scale invariant rarefaction wave) for PBX 9502 as a validation test of the implementation of the SURF and SURFplus models in the xRage code. Even with a fairly fine uniform mesh (12,800 cells for 100mm) the detonation wave profile had limited resolution due to the thin reaction zone width (0.18mm) for the fast SURF burn rate. Here we study the effect of finer resolution by comparing results of simulations with cell sizes of 8, 2 and 1 μm, which corresponds to 25, 100 andmore » 200 points within the reaction zone. With finer resolution the lead shock pressure is closer to the von Neumann spike pressure, and there is less noise in the rarefaction wave due to fluctuations within the reaction zone. As a result the average error decreases. The pointwise error is still dominated by the smearing the pressure kink in the vicinity of the sonic point which occurs at the end of the reaction zone.« less

How to study the aetiology of burn injury: the epidemiological approach.

PubMed

Bouter, L M; Knipschild, P G; van Rijn, J L; Meertens, R M

1989-06-01

Effective prevention of burn injury should be based on sound aetiological knowledge. This article deals with epidemiological methods to study the incidence of burn injury as a function of its risk factors. Central methodological issues are comparability of baseline prognosis, comparability of measurements (of effects in cohort studies and of risk factors in case-control studies), and comparability of external circumstances. These principles are clarified with a number of fictitious examples of risk factors for burn injury. It is explained that in preventive trials comparability may be achieved by randomization, blinding and placebo intervention. The main tools in non-experimental studies are deliberate selection and multivariate analysis. Special attention is given to the definition of the source population and to reducing measurement incomparability in case-control studies. Some well-designed case-control studies following these principles might bring effective prevention of burn injury some steps nearer.

Elevated thrombopoietin in plasma of burned patients without and with sepsis enhances platelet activation.

PubMed

Lupia, E; Bosco, O; Mariano, F; Dondi, A E; Goffi, A; Spatola, T; Cuccurullo, A; Tizzani, P; Brondino, G; Stella, M; Montrucchio, G

2009-06-01

Thrombopoietin (TPO) is a humoral growth factor that does not induce platelet aggregation per se, but enhances platelet activation in response to several agonists. Circulating levels of TPO are increased in patients with sepsis and are mainly related to sepsis severity. To investigate the potential contribution of elevated TPO levels in platelet activation during burn injury complicated or not by sepsis. We studied 22 burned patients, 10 without and 12 with sepsis, and 10 healthy subjects. We measured plasma levels of TPO, as well as leukocyte-platelet binding and P-selectin expression. The priming activity of plasma from burned patients or healthy subjects on platelet aggregation and leukocyte-platelet binding, and the role of TPO in these effects were also studied in vitro. Burned patients without and with sepsis showed higher circulating TPO levels and increased monocyte-platelet binding compared with healthy subjects. Moreover, TPO levels, monocyte-platelet binding and P-selectin expression were significantly higher in burned patients with sepsis than in burned patients without sepsis. In vitro, plasma from burned patients without and with sepsis, but not from healthy subjects, primed platelet aggregation, monocyte-platelet binding and platelet P-selectin expression. The effect of plasma from burned patients with sepsis was significantly higher than that of plasma from burned patients without sepsis. An inhibitor of TPO prevented the priming effect of plasma from burned patients. Increased TPO levels may enhance platelet activation during burn injury and sepsis, potentially participating in the pathogenesis of multi-organ failure in these diseases.

Benzo(a)pyrene accumulation in soils of technogenic emission zone by subcritical water extraction method

NASA Astrophysics Data System (ADS)

Sushkova, Svetlana; Minkina, Tatiana; Kizilkaya, Ridvan; Mandzhieva, Saglara; Batukaev, Abdulmalik; Bauer, Tatiana; Gulser, Coskun

2016-04-01

The purpose of research is the assessment of main marker of polycyclic aromatic hydrocarbons contamination, benzo[a]pyrene (BaP) content in soils of emission zone of the power complex plant in soils with use of ecologically clean and effective subcritical water extraction method. Studies were conducted on the soils of monitoring plots subjected to Novocherkassk Power Plant emissions from burning coal. In 2000, monitoring plots were established at different distances from the NPS (1.0-20.0 km). Soil samples for the determination of soil properties and the contents of BaP were taken from a depth of 0-20 cm. The soil cover in the region under study consisted of ordinary chernozems, meadow-chernozemic soils, and alluvial meadow soils. This soil revealed the following physical and chemical properties: Corg-3.1-5.0%, pH-7.3-7.6, ECE-31.2-47.6 mmol(+)/100g; CaCO3-0.2-1.0%, the content of physical clay - 51-67% and clay - 3-37%. BaP extraction from soils was carried out by a subcritical water extraction method. Subcritical water extraction of BaP from soil samples was conducted in a specially developed extraction cartridge made of stainless steel and equipped with screw-on caps at both ends. It was also equipped with a manometer that included a valve for pressure release to maintain an internal pressure of 100 atm. The extraction cartridge containing a sample and water was placed into an oven connected to a temperature regulator under temperature 250oC and pressure 60 atm. The BaP concentration in the acetonitrile extract was determined by HPLC. The efficiency of BaP extraction from soil was determined using a matrix spike. The main accumulation of pollutant in 20 cm layer of soils is noted directly in affected zone on the plots situated at 1.2, 1.6, 5.0, 8.0 km from emission source in the direction of prevailing winds. The maximum quantity of a pollutant was founded in the soil of the plot located mostly close to a source of pollution in the direction of prevailing winds. Value from 2012 to 2013 reached to 316.5 mkg/kg in 5 cm soil layer and 217.8 mkg/kg in 5-20 cm soil layer that exceeded the BaP maximum concentration limit level in the soil up to 15 times. The maximum limited concentration of BaP in soil is 20 mkg/kg according Russian Federation legislation. Thus, a method of BaP determination in soils has been approved as based upon the subcritical water extraction under the optimum conditions. The efficiency of the given method involves the use of subcritical water as an environmentally friendly solvent, a shorter time for environmental analysis. BaP distribution and accumulation tendencies were investigated during the 2 years of monitoring researches in studied soils. The main factor of technogenic influence on the soil the investigated area are toxic emissions of a power complex plant from burning coal. Despite the environmental activities of in the enterprise, the impact of emissions on the environment location nearby today is still primary. This research was supported by projects of the Ministry of Education and Science of Russia, no. 5.885.2014/K and Grant of President of Russian Federation no. MK-6827.2015.4, RFBR no. 15-35-21134.

Fire control method and analytical model for large liquid hydrocarbon pool fires

NASA Technical Reports Server (NTRS)

Fenton, D. L.

1986-01-01

The dominate parameter governing the behavior of a liquid hydrocarbon (JP-5) pool fire is wind speed. The most effective method of controlling wind speed in the vicinity of a large circular (10 m dia.) pool fire is a set of concentric screens located outside the perimeter. Because detailed behavior of the pool fire structure within one pool fire diameter is unknown, an analytical model supported by careful experiments is under development. As a first step toward this development, a regional pool fire model was constructed for the no-wind condition consisting of three zones -- liquid fuel, combustion, and plume -- where the predicted variables are mass burning rate and characteristic temperatures of the combustion and plume zones. This zone pool fire model can be modified to incorporate plume bending by wind, radiation absorption by soot particles, and a different ambient air flow entrainment rate. Results from the zone model are given for a pool diameter of 1.3 m and are found to reproduce values in the literature.

Importance of transboundary transport of biomass burning emissions to regional air quality in Southeast Asia

NASA Astrophysics Data System (ADS)

Aouizerats, B.; van der Werf, G. R.; Balasubramanian, R.; Betha, R.

2014-05-01

Smoke from biomass and peat burning has a notable impact on ambient air quality and climate in the Southeast Asia (SEA) region. We modeled the largest fire-induced haze episode in the past decade (2006) in Indonesia using the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem). We focused mainly on the evolution of the fire plume composition and its interaction with the urbanized area of the city-state of Singapore, and on comparisons of modeled and measured aerosol and CO concentrations. Two simulations were run with the model using the complex Volatility Basis Set (VBS) scheme to reproduce primary and secondary aerosol evolution and concentration. The first simulation referred to as WRF-FIRE included anthropogenic, biogenic, and b iomass burning emissions from the Global Fire Emissions Database (GFED3) while the second simulation referred to as WRF-NOFIRE was run without emissions from biomass burning. To test model performance, we used three independent datasets for comparison including airborne measurements of Particulate Matter with a diameter of 10 μm or less (PM10) in Singapore, CO measurements in Sumatra, and Aerosol Optical Depth (AOD) column observations from 4 satellite-based sensors. We found reasonable agreement of the model runs with both ground-based measurements of CO and PM10. The comparison with AOD was less favorable and indicated the model underestimated AOD, although the degree of mismatch varied between different satellite data sets. During our study period, forest and peat fires in Sumatra were the main cause of enhanced aerosol concentrations from regional transport over Singapore. Analysis of the biomass burning plume showed high concentrations of primary organic aerosols (POA) with values up to 600 μg m-3 over the fire locations. The concentration of POA remained quite stable within the plume between the main burning region and Singapore while secondary organic aerosol (SOA) concentration slightly increased. The absolute values of SOA (up to 20 μg m-3) were much lower than those from POA, indicating a minor role of SOA in biomass burning plumes. Our results show that about 21% of the total mass loading of ambient PM10 during the July-October study period in Singapore was due to biomass and peat burning in Sumatra, but this contribution increased during high burning periods. In total, our model results indicated that during 35 days aerosol concentrations in Singapore were above the threshold of 50 μg m-3 day-1 indicating poor air quality. During 17 days this was due to fires, based on the difference between the simulations with and without fires. Local pollution in combination with recirculation of air masses was probably the main cause of poor air quality during the other 18 days, although fires from Sumatra and probably also from Borneo added to the enhanced PM10 concentrations. The model vs. measurement comparisons highlighted that for our study period and region the GFED3 biomass burning aerosol emissions were more in line with observations than found in other studies. This indicates that care should be taken when using AOD to constrain emissions or estimate ground-level air quality. This study also shows the need for relatively high resolution modeling to accurately reproduce the advection of air masses necessary to quantify the impacts and feedbacks on air quality.

End of the Line for a Star like Ours

ERIC Educational Resources Information Center

Riddle, Bob

2010-01-01

Stars of different masses have varying life spans, with the more massive stars "burning out" more quickly than stars of lower masses. How or what they do when they burn out also varies, depending on the mass of the star. All stars are called "main sequence stars" as they continue fusing hydrogen and staying in a state of equilibrium--a balance…

A comprehensive biomass burning emission inventory with high spatial and temporal resolution in China

NASA Astrophysics Data System (ADS)

Zhou, Ying; Xing, Xiaofan; Lang, Jianlei; Chen, Dongsheng; Cheng, Shuiyuan; Wei, Lin; Wei, Xiao; Liu, Chao

2017-02-01

Biomass burning injects many different gases and aerosols into the atmosphere that could have a harmful effect on air quality, climate, and human health. In this study, a comprehensive biomass burning emission inventory including domestic and in-field straw burning, firewood burning, livestock excrement burning, and forest and grassland fires is presented, which was developed for mainland China in 2012 based on county-level activity data, satellite data, and updated source-specific emission factors (EFs). The emission inventory within a 1 × 1 km2 grid was generated using geographical information system (GIS) technology according to source-based spatial surrogates. A range of key information related to emission estimation (e.g. province-specific proportion of domestic and in-field straw burning, detailed firewood burning quantities, uneven temporal distribution coefficient) was obtained from field investigation, systematic combing of the latest research, and regression analysis of statistical data. The established emission inventory includes the major precursors of complex pollution, greenhouse gases, and heavy metal released from biomass burning. The results show that the emissions of SO2, NOx, PM10, PM2.5, NMVOC, NH3, CO, EC, OC, CO2, CH4, and Hg in 2012 are 336.8 Gg, 990.7 Gg, 3728.3 Gg, 3526.7 Gg, 3474.2 Gg, 401.2 Gg, 34 380.4 Gg, 369.7 Gg, 1189.5 Gg, 675 299.0 Gg, 2092.4 Gg, and 4.12 Mg, respectively. Domestic straw burning, in-field straw burning, and firewood burning are identified as the dominant biomass burning sources. The largest contributing source is different for various pollutants. Domestic straw burning is the largest source of biomass burning emissions for all the pollutants considered, except for NH3, EC (firewood), and NOx (in-field straw). Corn, rice, and wheat represent the major crop straws. The combined emission of these three straw types accounts for 80 % of the total straw-burned emissions for each specific pollutant mentioned in this study. As for the straw burning emission of various crops, corn straw burning has the largest contribution to all of the pollutants considered, except for CH4; rice straw burning has highest contribution to CH4 and the second largest contribution to other pollutants, except for SO2, OC, and Hg; wheat straw burning is the second largest contributor to SO2, OC, and Hg and the third largest contributor to other pollutants. Heilongjiang, Shandong, and Henan provinces located in the north-eastern and central-southern regions of China have higher emissions compared to other provinces in China. Gridded emissions, which were obtained through spatial allocation based on the gridded rural population and fire point data from emission inventories at county resolution, could better represent the actual situation. High biomass burning emissions are concentrated in the areas with more agricultural and rural activity. The months of April, May, June, and October account for 65 % of emissions from in-field crop residue burning, while, regarding EC, the emissions in January, February, October, November, and December are relatively higher than other months due to biomass domestic burning in heating season. There are regional differences in the monthly variations of emissions due to the diversity of main planted crops and climatic conditions. Furthermore, PM2.5 component results showed that OC, Cl-, EC, K+, NH4+, elemental K, and SO42- are the main PM2.5 species, accounting for 80 % of the total emissions. The species with relatively high contribution to NMVOC emission include ethylene, propylene, toluene, mp-xylene, and ethyl benzene, which are key species for the formation of secondary air pollution. The detailed biomass burning emission inventory developed by this study could provide useful information for air-quality modelling and could support the development of appropriate pollution-control strategies.

Electrical burns: The trend and risk factors in the Ghanaian population.

PubMed

Agbenorku, P; Agbenorku, E; Akpaloo, J; Obeng, G; Agbley, D

2014-12-31

The usefulness of electricity in daily life offers several advantages which cannot be underestimated. Electricity is needed by industries for manufacturing and also in homes for lighting, cooking, washing, etc. However, electricity can cause severe life-threatening complications. This study investigates the trend and mortality risk factors of electrical burn injuries at the Burns Intensive Care Unit (BICU) of the Komfo Anokye Teaching Hospital (KATH), Ghana. The Burns Registry at KATH BICU containing information on patients who were admitted for electrical burns was used. Data on the sex, age, occupation, cause of injury, Total Body Surface Area burned (TBSA) and outcome of admissions was obtained. GraphPad version 5 was used for the analysis. There were 13 (2.7%) electrical burns, suffered by 11 males (84.6%) and 2 females (15.4%) out of a total 487 BICU admissions over a 4-year period (July 1, 2009 - June 30, 2013); the mean age of the electrical burn victims was 37.8 years (range = 22-56); the TBSA ranged from 5.0% - 98.0%. Mortality risk factors identified were high voltage electrical burns, older age (P=0.0250) and TBSA>20% (P=0.048). Four cases (30.8%) were transferred to the Main Burns Ward (Ward D2C); 6 cases (46.1%) were discharged home; 3 patients (23.1%) died; all deaths were recorded in persons who had high voltage electrical burns. Electrical burns can be severe and can cause death. Even though the current study showed that a small population was affected by electrical burns, society has to be continually conscious of the detrimental effects of electrical energy and take the necessary precautions to minimize this type of accident.

Electrical burns: The trend and risk factors in the Ghanaian population

PubMed Central

Agbenorku, P.; Agbenorku, E.; Akpaloo, J.; Obeng, G.; Agbley, D.

2014-01-01

Summary The usefulness of electricity in daily life offers several advantages which cannot be underestimated. Electricity is needed by industries for manufacturing and also in homes for lighting, cooking, washing, etc. However, electricity can cause severe life-threatening complications. This study investigates the trend and mortality risk factors of electrical burn injuries at the Burns Intensive Care Unit (BICU) of the Komfo Anokye Teaching Hospital (KATH), Ghana. The Burns Registry at KATH BICU containing information on patients who were admitted for electrical burns was used. Data on the sex, age, occupation, cause of injury, Total Body Surface Area burned (TBSA) and outcome of admissions was obtained. GraphPad version 5 was used for the analysis. There were 13 (2.7%) electrical burns, suffered by 11 males (84.6%) and 2 females (15.4%) out of a total 487 BICU admissions over a 4-year period (July 1, 2009 – June 30, 2013); the mean age of the electrical burn victims was 37.8 years (range = 22–56); the TBSA ranged from 5.0% - 98.0%. Mortality risk factors identified were high voltage electrical burns, older age (P=0.0250) and TBSA>20% (P=0.048). Four cases (30.8%) were transferred to the Main Burns Ward (Ward D2C); 6 cases (46.1%) were discharged home; 3 patients (23.1%) died; all deaths were recorded in persons who had high voltage electrical burns. Electrical burns can be severe and can cause death. Even though the current study showed that a small population was affected by electrical burns, society has to be continually conscious of the detrimental effects of electrical energy and take the necessary precautions to minimize this type of accident. PMID:26336364

Health-related quality of life (EQ-5D) early after injury predicts long-term pain after burn.

PubMed

Gauffin, Emelie; Öster, Caisa; Sjöberg, Folke; Gerdin, Bengt; Ekselius, Lisa

2016-12-01

Chronic pain after burn can have severe physical and psychological effects on former patients years after the initial injury. Although the issue of pain after burn has gained increased attention over the past years, prospective, longitudinal studies are scarce. Our aim was to prospectively investigate consecutive burn patients for pain severity over time and to evaluate the prevalence and characteristics of post-burn pain to 2-7 years after the burn. As an additional aim, the effects of burn and individual-related factors, especially health-related Quality of Life (HRQoL), were investigated. Sixty-seven consecutive burn patients were assessed during acute care at 3, 6, 12 and 24 months, as well as at 2-7 years post-burn. HRQoL, symptoms of post-traumatic stress disorder (PTSD) and other psychiatric disorders were investigated. During the interviews that took place 2-7 years after the injury (mean 4.6±1.9 years), current chronic post-burn pain was assessed using the Brief Pain Inventory-Short Form (BPI-SF). One-third of the patients still reported pain 2-7 years after the injury. Pain severity and interference with daily life were mainly mild to moderate though they were found to be associated with significantly lower HRQoL. Chronic pain after burn was associated with both burn- and individual-related factors. In logistic regression analysis HRQoL at 3 and 12 months and symptoms of PTSD at 12 months were independent factors in predicting chronic pain after burn. Pain after burn becomes a chronic burden for many former burn patients and decreases HRQoL. A novel finding in this study was that HRQoL assessed early after burn was a predictor for the development of chronic pain. This finding may help to predict future pain problems and serve as an indicator for pain preventive measures. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

LUNA: Status and prospects

NASA Astrophysics Data System (ADS)

Broggini, C.; Bemmerer, D.; Caciolli, A.; Trezzi, D.

2018-01-01

The essential ingredients of nuclear astrophysics are the thermonuclear reactions which shape the life and death of stars and which are responsible for the synthesis of the chemical elements in the Universe. Deep underground in the Gran Sasso Laboratory the cross sections of the key reactions responsible for the hydrogen burning in stars have been measured with two accelerators of 50 and 400 kV voltage right down to the energies of astrophysical interest. As a matter of fact, the main advantage of the underground laboratory is the reduction of the background. Such a reduction has allowed, for the first time, to measure relevant cross sections at the Gamow energy. The qualifying features of underground nuclear astrophysics are exhaustively reviewed before discussing the current LUNA program which is mainly devoted to the study of the Big-Bang nucleosynthesis and of the synthesis of the light elements in AGB stars and classical novae. The main results obtained during the study of reactions relevant to the Sun are also reviewed and their influence on our understanding of the properties of the neutrino, of the Sun and of the Universe itself is discussed. Finally, the future of LUNA during the next decade is outlined. It will be mainly focused on the study of the nuclear burning stages after hydrogen burning: helium and carbon burning. All this will be accomplished thanks to a new 3.5 MV accelerator able to deliver high current beams of proton, helium and carbon which will start running under Gran Sasso in 2019. In particular, we will discuss the first phase of the scientific case of the 3.5 MV accelerator focused on the study of 12C+12C and of the two reactions which generate free neutrons inside stars: 13C(α,n)16O and 22Ne(α,n)25Mg.

Somatosensory Rehabilitation for Neuropathic Pain in Burn Survivors: A Case Series.

PubMed

Nedelec, Bernadette; Calva, Valerie; Chouinard, Annick; Couture, Marie-Andrée; Godbout, Elisabeth; de Oliveira, Ana; LaSalle, Léo

2016-01-01

Neuropathic pain is an enormous rehabilitation challenge that has a substantial negative effect on patient function and quality of life. Somatosensory rehabilitation is a novel, nonpharmacological intervention described by Spicher based on the neuroplasticity of the somatosensory system. The rationale for somatosensory rehabilitation is that treating hypoesthesia will decrease neuropathic pain. Particularly for those with established neuropathic pain, the hypoesthesia may be masked by mechanical allodynia, which must be treated before treating the underlying hyposensitive zone. This case series describes the outcome of 17 burn survivors treated with somatosensory rehabilitation for their neuropathic pain. Before initiating treatment a modified version of the McGill Pain Questionnaire-short form (Questionnaire de la douleur St. Antoine, QDSA) was completed with the patients. The total score (×/64) was converted to percentage. The mechanical allodynia was assessed with the Rainbow Pain Scale that uses touch with the 15-g Semmes Weinstein Monofilaments (SWMs) and that was rated as painful on the visual analog scale (3/10 or resting pain + 1/10), as the criteria for mechanical allodynia. The severity level was assessed using seven predetermined SWMs to identify the smallest that elicited pain. The treatment consisted of avoiding all touch in the allodynic zone while concurrently providing proximal sensory and vibratory counter stimulation. Once the mechanical allodynia was eliminated, the underlying hypoesthesia was treated. Hypoesthesia was evaluated with the SWMs, and the percent improvement from baseline was calculated. The sensory reeducation treatment for hypoesthesia consisted of touch discrimination, texture perception, and vibratory stimulation. Seventeen patients (71/29% male/female, 21 ± 25% TBSA burned, 486 ± 596 days postburn) were evaluated and treated. Of these 15 initially presented with mechanical allodynia. The SWM scores had improved by 27 ± 21% (n = 14) and 29 ± 26% (n = 12) at 2 and 3 months posttreatment, respectively. The QDSA scores had improved by 9 ± 14% (n = 8) and 23 ± 23% (n = 6) at 2 and 3 months posttreatment, respectively. There were two patients who initially presented with hypoesthesia and six who had their zone of hypoesthesia treated after the mechanical allodynia had resolved. For these eight patients, their ability to perceive light touch improved by 27 ± 17% (n = 8) and 35 ± 25% (n = 6) at 2 and 3 months postsensory reeducation treatment initiation, respectively. The QDSA improved by 9 and 50% for the two patients who initially presented with hypoesthesia. In this case series, the majority of patients (13/17 or 76%) showed substantial improvements after somatosensory rehabilitation suggesting this is a treatment approach that should be considered with burn survivors experiencing neuropathic pain. There is a need, however, for future controlled studies to further investigate this approach and to determine if there is a subpopulation of burn survivors that are more likely than others to benefit from this approach.

Fire, red squirrels, whitebark pine, and Yellowstone grizzly bears

USGS Publications Warehouse

Podruzny, Shannon; Reinhart, Daniel P.; Mattson, David J.

1999-01-01

Whitebark pine (Pinus albicaulis) habitats are important to Yellowstone grizzly bears (Ursus arctos) as refugia and sources of food. Ecological relationships between whitebark pine, red squirrels (Tamiasciurus hudsonicus), and grizzly bear use of pine seeds on Mt. Washburn in Yellowstone National Park, Wyoming, were examined during 1984-86. Following large-scale fires in 1988, we repeated the study in 1995-97 to examine the effects of fire on availability of whitebark pine seed in red squirrel middens and on bear use of middens. Half of the total length of the original line transects burned. We found no red squirrel middens in burned areas. Post-fire linear-abundance (no./km) of active squirrel middens that were pooled from burned and unburned areas decreased 27% compared to pre-fire abundance, but increased in unburned portions of some habitat types. Mean size of active middens decreased 54% post-fire. Use of pine seeds by bears (linear abundance of excavated middens) in pooled burned and unburned habitats decreased by 64%, likely due to the combined effects of reduced midden availability and smaller midden size. We discourage any further large-scale losses of seed producing trees from management-prescribed fires or timber harvesting until the effects of fire on ecological relationships in the whitebark pine zone are better understood.

77 FR 40147 - Boston and Maine Corporation-Abandonment Exemption-in Worcester County, MA

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-06

... DEPARTMENT OF TRANSPORTATION Surface Transportation Board [Docket No. AB 32 (Sub-No. 105X)] Boston and Maine Corporation--Abandonment Exemption--in Worcester County, MA Boston and Maine Corporation (B.... Burns, Iron Horse Park, North Billerica, MA 01862. If the verified notice contains false or misleading...

Evaluation of the FEERv1.0 Global Top-Down Biomass Burning Emissions Inventory over Africa

NASA Astrophysics Data System (ADS)

Ellison, L.; Ichoku, C. M.

2014-12-01

With the advent of the Fire Energetics and Emissions Research (FEER) global top-down biomass burning emissions product from NASA Goddard Space Flight Center, a subsequent effort is going on to analyze and evaluate some of the main (particulate and gaseous) constituents of this emissions inventory against other inventories of biomass burning emissions over the African continent. There is consistent and continual burning during the dry season in NSSA of many small slash-and-burn fires that, though may be relatively small fires individually, collectively contribute 20-25% of the global total carbon emissions from biomass burning. As a top-down method of estimating biomass-burning emissions, FEERv1.0 is able to yield higher and more realistic emissions than previously obtainable using bottom-up methods. Results of such comparisons performed in detail over Africa will be discussed in this presentation. This effort is carried out in conjunction with a NASA-funded interdisciplinary research project investigating the effects of biomass burning on the regional climate system in Northern Sub-Saharan Africa (NSSA). Essentially, that project aims to determine how fires may have affected the severe droughts that plagued the NSSA region in recent history. Therefore, it is imperative that the biomass burning emissions input data over Africa be as accurate as possible in order to obtain a confident understanding of their interactions and feedbacks with the hydrological cycle in NSSA.

Epidemiology of paediatric burns in Lithuania: focus on a vulnerable population exposed to the risk of scalds at home without hot tap water supply.

PubMed

Kubilius, Darius; Smailytė, Giedrė; Rimdeikienė, Inesa; Malcius, Dalius; Kaikaris, Vygintas; Rimdeika, Rytis

2014-05-01

To describe the epidemiology of paediatric burns in Lithuania, identify the trends of burn occurrence, the vulnerable population and aetiology. This study was based on all inclusive national information obtained from the National Health Insurance database for the period of 2001-2010. Information on the burns aetiology was collected in the Hospital of Lithuanian University of Heath Sciences Kauno Klinikos. 7146 children in the age group of 0-14 were hospitalized in Lithuania and constituted 44% of all admissions due to burns. The incidence among boys was 149.8 and among girls 99.9 per 100,000. The highest risk of burns was observed from 11 to 15 months of age. Scalding in 0-1 years age group composed 96% of all burns in this age group. Children younger than 2 years of age are a vulnerable population of burns in Lithuania. Scalding was main cause of their burns. The aetiological subgroups of scalding were scalding with hot drinks/food and scalding with hot water meant for household. The major part of scalding with hot drinks was due to scalding with parents' drinks. Scalding with hot water meant for household is associated with the lack of hot water supply. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

Regional paleofire regimes affected by non-uniform climate, vegetation and human drivers

PubMed Central

Blarquez, Olivier; Ali, Adam A.; Girardin, Martin P.; Grondin, Pierre; Fréchette, Bianca; Bergeron, Yves; Hély, Christelle

2015-01-01

Climate, vegetation and humans act on biomass burning at different spatial and temporal scales. In this study, we used a dense network of sedimentary charcoal records from eastern Canada to reconstruct regional biomass burning history over the last 7000 years at the scale of four potential vegetation types: open coniferous forest/tundra, boreal coniferous forest, boreal mixedwood forest and temperate forest. The biomass burning trajectories were compared with regional climate trends reconstructed from general circulation models, tree biomass reconstructed from pollen series, and human population densities. We found that non-uniform climate, vegetation and human drivers acted on regional biomass burning history. In the open coniferous forest/tundra and dense coniferous forest, the regional biomass burning was primarily shaped by gradual establishment of less climate-conducive burning conditions over 5000 years. In the mixed boreal forest an increasing relative proportion of flammable conifers in landscapes since 2000 BP contributed to maintaining biomass burning constant despite climatic conditions less favourable to fires. In the temperate forest, biomass burning was uncoupled with climatic conditions and the main driver was seemingly vegetation until European colonization, i.e. 300 BP. Tree biomass and thus fuel accumulation modulated fire activity, an indication that biomass burning is fuel-dependent and notably upon long-term co-dominance shifts between conifers and broadleaf trees. PMID:26330162

Application of Haddon's matrix in qualitative research methodology: an experience in burns epidemiology.

PubMed

Deljavan, Reza; Sadeghi-Bazargani, Homayoun; Fouladi, Nasrin; Arshi, Shahnam; Mohammadi, Reza

2012-01-01

Little has been done to investigate the application of injury specific qualitative research methods in the field of burn injuries. The aim of this study was to use an analytical tool (Haddon's matrix) through qualitative research methods to better understand people's perceptions about burn injuries. This study applied Haddon's matrix as a framework and an analytical tool for a qualitative research methodology in burn research. Both child and adult burn injury victims were enrolled into a qualitative study conducted using focus group discussion. Haddon's matrix was used to develop an interview guide and also through the analysis phase. The main analysis clusters were pre-event level/human (including risky behaviors, belief and cultural factors, and knowledge and education), pre-event level/object, pre-event phase/environment and event and post-event phase (including fire control, emergency scald and burn wound management, traditional remedies, medical consultation, and severity indicators). This research gave rise to results that are possibly useful both for future injury research and for designing burn injury prevention plans. Haddon's matrix is applicable in a qualitative research methodology both at data collection and data analysis phases. The study using Haddon's matrix through a qualitative research methodology yielded substantially rich information regarding burn injuries that may possibly be useful for prevention or future quantitative research.

Effectiveness of prescribed fire to re-establish sagebrush vegetation and ecohydrologic function on woodland-encroached sagebrush steppe, Great Basin, USA

NASA Astrophysics Data System (ADS)

Williams, C. J.; Pierson, F. B.; Kormos, P.; Al-Hamdan, O. Z.; Nouwakpo, S.; Weltz, M.; Vega, S.; Lindsay, K.

2017-12-01

Range expansion of pinyon (Pinus spp.) and juniper (Juniperus spp.) conifers into sagebrush steppe (Artemisia spp.) communities has imperiled a vast domain in the western US. Encroachment of sagebrush ecosystems by pinyon and juniper conifers has negative ramifications to ecosystem structure and function and delivery of goods and services. Scientists, land management agencies, and private land owners throughout the western US are challenged with selecting from a suite of options to reduce pinyon and juniper woody fuels and re-establish sagebrush steppe structure and function. This study evaluated the effectiveness of prescribed fire to re-establish sagebrush vegetation and ecohydrologic function over a 9 yr period. Nine years post-fire hydrologic and erosion responses reflect the combination of pre-fire site conditions, perennial grass recruitment, delayed litter cover, and inherent site characteristics. Burning initially increased bare ground, runoff, and erosion for well-vegetated areas underneath tree and shrub canopies, but had minimal impact on hydrology and erosion for degraded interspaces between plants. The degraded interspaces were primarily bare ground and exhibited high runoff and erosion rates prior to burning. Initial fire effects persisted for two years, but increased productivity of grasses improved hydrologic function of interspaces over the full 9 yr period. At the hillslope scale, grass recruitment in the intercanopy between trees reduced runoff from rainsplash, sheetflow, and concentrated overland flow at one site, but did not reduce the high levels of runoff and erosion from a more degraded site. In areas formerly occupied by trees (tree zones), burning increased invasive annual grass cover due to fire removal of limited native perennial plants and competition for resources. The invasive annual grass cover had no net effect on runoff and erosion from tree zones however. Runoff and erosion increased in tree zones at the more degraded site due to delayed litter recruitment and persistence of bare ground conditions. Overall, the 9 yr study illustrates the ecohydrologic complexities with predicting sagebrush ecosystem responses to woodland encroachment and tree removal.

Socioeconomic impact of children's burns-a pilot study.

PubMed

Kilburn, Nadia; Dheansa, Baljit

2014-12-01

This pilot study aimed to gain empirical data on the social and economic impacts of child burns on children and parents, in the context of the outpatient setting. A questionnaire was completed by 52 parents of paediatric patients attending the burns outpatient department at Queen Victoria Hospital (QVH), East Grinstead, for at least the third time. Children's medical notes were used to extract demographic and medical data. Quantitative data was analyzed statistically and qualitative data was analyzed manually using content analysis. The financial burden related to the injury posed the greatest impact on parents, and was mainly associated with making the journey to the hospital, with lower income households being most affected. Self-employed parents and those who had to attend more than 6 hospital appointments also ran into difficulties. On the whole, there was not a considerable social impact on the burn-injured child, which may reflect the minor nature of burns in this study (mean depth partial thickness, median TBSA 1.0%). Parents were shown to perceive a greater impact from their child's burn injury than their child. Certain groups of parents were identified as requiring additional support following the burn injury. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

[The Nutrition Care of Severe Burn Patients].

PubMed

Hsieh, Yu-Hsiu

2016-02-01

In addition to recent advances in burn patient care techniques such as maintaining warm circumambient temperature, the early excision of wounds, and the use of closed dressing, providing nutrition support through early feeding has proven instrumental in greatly increasing the survival rate of burn patients. Severe burns complicated by many factors initiate tremendous physiological stress that leads to postburn hypermetabolism that includes enhanced tissue catabolism, the loss of muscle mass, and decreases in the body's reservoirs of protein and energy. These problems have become the focus of burn therapy. Treating severe burns aims not only to enhance survival rates but also to restore normal bodily functions as completely as possible. Recent research evaluating the application of anabolic agents and immune-enhance formula for severe burns therapy has generated significant controversy. Inadequate caloric intake is one of the main differences among the related studies, with the effect of many special nutrients such as bran acid amides not taken into consideration. Therefore, considering the sufficiency of caloric and protein intake is critical in assessing effectiveness. Only after patients receive adequate calories and protein may the effect of special nutrients such as glutamine and supplements be evaluated effectively.

The effect of azeotropism on combustion characteristics of blended fuel pool fire.

PubMed

Ding, Yanming; Wang, Changjian; Lu, Shouxiang

2014-04-30

The effect of azeotropism on combustion characteristics of blended fuel pool fire was experimentally studied in an open fire test space of State Key Laboratory of Fire Science. A 30 cm × 30 cm square pool filled with n-heptane and ethanol blended fuel was employed. Flame images, burning rate and temperature distribution were collected and recorded in the whole combustion process. Results show that azeotropism obviously dominates the combustion behavior of n-heptane/ethanol blended fuel pool fire. The combustion process after ignition exhibits four typical stages: initial development, azeotropic burning, single-component burning and decay stage. Azeotropism appears when temperature of fuel surface reaches azeotropic point and blended fuel burns at azeotropic ratio. Compared with individual pure fuel, the effect of azeotropism on main fire parameters, such as flame height, burning rate, flame puffing frequency and centerline temperature were analyzed. Burning rate and centerline temperature of blended fuel are higher than that of individual pure fuel respectively at azeotropic burning stage, and flame puffing frequency follows the empirical formula between Strouhal and Froude number for pure fuel. Copyright © 2014 Elsevier B.V. All rights reserved.

Fast and Luminous Transients from the Explosions of Long-lived Massive White Dwarf Merger Remnants

NASA Astrophysics Data System (ADS)

Brooks, Jared; Schwab, Josiah; Bildsten, Lars; Quataert, Eliot; Paxton, Bill; Blinnikov, Sergei; Sorokina, Elena

2017-12-01

We study the evolution and final outcome of long-lived (≈ {10}5 years) remnants from the merger of an He white dwarf (WD) with a more massive C/O or O/Ne WD. Using Modules for Experiments in Stellar Astrophysics ({\\mathtt{MESA}}), we show that these remnants have a red giant configuration supported by steady helium burning, adding mass to the WD core until it reaches {M}{core}≈ 1.12{--}1.20 {M}⊙ . At that point, the base of the surface convection zone extends into the burning layer, mixing the helium-burning products (primarily carbon and magnesium) throughout the convective envelope. Further evolution depletes the convective envelope of helium and dramatically slows the mass increase of the underlying WD core. The WD core mass growth re-initiates after helium depletion, as then an uncoupled carbon-burning shell is ignited and proceeds to burn the fuel from the remaining metal-rich extended envelope. For large enough initial total merger masses, O/Ne WD cores would experience electron-capture triggered collapse to neutron stars (NSs) after growing to near Chandrasekhar mass ({M}{Ch}). Massive C/O WD cores could suffer the same fate after a carbon-burning flame converts them to ONe. The NS formation would release ≈ {10}50 erg into the remaining extended low mass envelope. Using the STELLA radiative transfer code, we predict the resulting optical light curves from these exploded envelopes. Reaching absolute magnitudes of {M}V≈ -17, these transients are bright for about one week and have many features of the class of luminous, rapidly evolving transients studied by Drout and collaborators.

A century of Amazon burning driven by Atlantic climate

NASA Astrophysics Data System (ADS)

Makou, M.; Thompson, L. G.; Davis, M. E.; Eglinton, T. I.

2011-12-01

Very little is known about annual burning trends in the Amazon Basin prior to remote sensing of fires beginning in the late 1970's. Fires reduce Amazon forest biomass and species richness, release pollutant aerosols, and impact the carbon cycle, compelling further investigation of fire-climate dynamics. We measured organic compounds derived from vegetation burning in ice core samples from the Quelccaya Ice Cap in Peru at better than annual resolution to reconstruct wet and dry season burning throughout the Twentieth Century. Variations in the abundance of methyl hexadecanoate, which is produced by thermal alteration of vascular plant alkanoic acids, were used as a proxy for past fire activity. Concentrations of this compound in Quelccaya ice varied strongly on seasonal, interannual, and decadal time scales over the last 100 years, with high-amplitude dry season variability and muted, decadal-scale changes in wet season fire activity. Decade-long periods of repeatedly enhanced burning occurred during the 1930's and 1960's when dry season precipitation was perpetually reduced, as evidenced by low stages of the Rio Negro. These decadal trends suggest that changes in dry season precipitation drive fire activity in the western Amazon and highlight the potential of Amazon forests to undergo repeated strong burning. Fires occurred during years when sea surface temperatures (SSTs) in the north tropical Atlantic were elevated and the north-south tropical Atlantic SST gradient was enhanced; this SST pattern likely displaced the intertropical convergence zone northward, driving subsidence and drought in the western and southern Amazon basin. Thus, our novel ice core record suggests that Amazon forest fire activity during the Twentieth Century was driven primarily by Atlantic climate processes, and future forest health will depend heavily on the evolution of tropical climate.

Effects of exotic grasses on soil seed banks in Southeastern Arizona grasslands

USGS Publications Warehouse

McLaughlin, S.P.; Bowers, Janice E.

2007-01-01

At the Appleton-Whittell Research Ranch, an ungrazed grassland preserve in southeastern Arizona, soil seed banks were sampled in June, August, and October 2002 and June 2003. Wildfire had previously burned 90% of the research ranch in May 2002. Seed density and species richness in burned native grassland (2 plots) were compared to those in burned exotic grassland (2 plots). Averaged over 4 sample dates, seed densities were as follows: burned native grassland, 591 ?? 243.1 seeds??m-2 and 784 ?? 334.9 seeds??m-2; burned exotic grassland, 501 ?? 198.9 seeds??m-2 and 196 ?? 123.8 seeds??m-2. Species richness in the seed bank, also averaged over 4 sample dates, was as follows: burned native grassland, 16.3 ?? 1.7 species??m -2 and 19.5 ?? 1.0 species??m-2; burned exotic grassland, 12.0 ?? 3.4 species??m-2 and 11.06 ?? 2.5 species??m-2. The seed bank of burned exotic grassland contained significantly fewer seeds and species than that of burned native grassland. In addition, the seed bank in burned exotic grassland comprised mainly exotic grasses, whereas annual and perennial herbs, most of them native, dominated the seed bank of burned native grassland. Of the 50 species detected in soil samples, only 20 had a persistent seed bank, and only 1 of these was a native perennial bunchgrass. The preponderance of transient species means that eradication of exotic grasses must be followed by reseeding of native grasses and herbs, perhaps repeatedly, if native grassland is to replace exotic grassland.

From protostellar to pre-main-sequence evolution

NASA Astrophysics Data System (ADS)

D'Antona, F.

I summarize the status of pre-main-sequence evolutionary tracks starting from the first steps dating back to the concept of Hayashi track. Understanding of the dynamical protostellar phase in the vision of Palla & Stahler, who introduced the concept of the deuterium burning thermostat and of stellar birthline, provided for a long time a link between the dynamical and hydrostatic evolution. Disk accretion however changed considerably the view, but re-introducing some ambiguities which must still be solved. The limitations and uncertainties in the mass and age determination from models for young stellar objects are summarized, but the burning of light elements is still a powerful observational signature.

[Lymphocyte metabolism in children with extensive burns].

PubMed

Artem'ev, S A; Nazarov, I P; Kamzalakova, N I; Bulygin, G V

2009-01-01

The results of the study lead to the conclusion that the development of burn disease in children is accompanied by significant lymphocytic structural metabolic changes that determine the functional capabilities of cells and the immune system as a whole. There is an evident activation of the glutathione antioxidant system, a drastic activation of enzymes that ensure Krebs cycle reactions, as well as activation of anaerobic processes. The above changes are mainly caused by the activated sympathoadrenal system that is characteristic of stresses. The knowledge about the metabolic mechanisms responsible for the development of cellular reactions to burn shock and burn disease permits specification of the elements of the pathogenesis of these severe conditions and substantiation of the possibility of using metabolic correction in the complex treatment of children with the above pathology.

Surgical treatment and management of the severely burn patient: Review and update.

PubMed

Gacto-Sanchez, P

Since one of the main challenges in treating acute burn injuries is preventing infection, early excising of the eschar and covering of the wound becomes critical. Non-viable tissue is removed by initial aggressive surgical debridement. Many surgical options for covering the wound bed have been described, although split-thickness skin grafts remain the standard for the rapid and permanent closure of full-thickness burns. Significant advances made in the past decades have greatly improved burns patient care, as such that major future improvements in survival rates seem to be more difficult. Research into stem cells, grafting, biomarkers, inflammation control, and rehabilitation will continue to improve individualized care and create new treatment options for these patients. Copyright © 2017 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.

Simulation of mixing in the quick quench region of a rich burn-quick quench mix-lean burn combustor

NASA Technical Reports Server (NTRS)

Shih, Tom I.-P.; Nguyen, H. Lee; Howe, Gregory W.; Li, Z.

1991-01-01

A computer program was developed to study the mixing process in the quick quench region of a rich burn-quick quench mix-lean burn combustor. The computer program developed was based on the density-weighted, ensemble-averaged conservation equations of mass, momentum (full compressible Navier-Stokes), total energy, and species, closed by a k-epsilon turbulence model with wall functions. The combustion process was modeled by a two-step global reaction mechanism, and NO(x) formation was modeled by the Zeldovich mechanism. The formulation employed in the computer program and the essence of the numerical method of solution are described. Some results obtained for nonreacting and reacting flows with different main-flow to dilution-jet momentum flux ratios are also presented.

Monitoring Soil Erosion on a Burned Site in the Mojave-Great Basin Transition Zone: Final Report for the Jacob Fire Site

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, Julianne; Etyemezian, Vic; Cablk, Mary E.

A historic return interval of 100 years for large fires in the U.S. southwestern deserts is being replaced by one where fires may reoccur as frequently as every 20 to 30 years. The shortened return interval, which translates to an increase in fires, has implications for management of Soil Corrective Action Units (CAUs) and Corrective Action Sites (CASs) for which the Department of Energy, National Nuclear Security Administration Nevada Field Office has responsibility. A series of studies was initiated at uncontaminated analog sites to better understand the possible impacts of erosion and transport by wind and water should contaminated soilmore » sites burn. The first of these studies was undertaken at the Jacob Fire site approximately 12 kilometers (7.5 miles) north of Hiko, Nevada. A lightning-caused fire burned approximately 200 hectares during August 6-8, 2008. The site is representative of a transition between Mojave and Great Basin desert ecoregions on the Nevada National Security Site (NNSS), where the largest number of Soil CAUs/CASs are located. The area that burned at the Jacob Fire site was primarily a Coleogyne ramosissima (blackbrush) and Ephedra nevadensis (Mormon tea) community, also an abundant shrub assemblage in the similar transition zone on the NNSS. This report summarizes three years of measurements after the fire. Seven measurement campaigns at the Jacob Fire site were completed. Measurements were made on burned ridge (upland) and drainage sites, and on burned and unburned sites beneath and between vegetation. A Portable In-Situ Wind Erosion Lab (PI-SWERL) was used to estimate emissions of suspended particles at different wind speeds. Context for these measurements was provided through a meteorological tower that was installed at the Jacob Fire site to obtain local, relevant environmental parameters. Filter samples, collected from the exhaust of the PI-SWERL during measurements, were analyzed for chemical composition. Runoff and water erosion were quantified through a series of rainfall/runoff simulation tests in which controlled amounts of water were delivered to the soil surface in a specified amount of time. Runoff data were collected from understory and interspace soils on burned ridge and drainage areas. Runoff volume and suspended sediment in the runoff were sampled; the particle size distribution of the sediment was determined by laboratory analysis. Several land surface and soil characteristics associated with runoff were integrated by the calculation of site-specific curve numbers. Several vegetation surveys were conducted to assess post-burn recovery. Data from plots in both burned and unburned areas included species identification, counts, and location. Characterization of fire-affected area included measures at both the landscape scale and at specific sites. Although wind erosion measurements indicate that there are seasonal influences on almost all parameters measured, several trends were observed. PI-SWERL measurements indicated the potential for PM10 windblown dust emissions was higher on areas that were burned compared to areas that were not. Among the burned areas, understory soils in drainage areas were the most emissive, and interspace soils along burned ridges were least emissive. By 34 months after the burn (MAB), at the end of the study, emissions from all burned soil sites were virtually indistinguishable from unburned levels. Like the amount of emissions, the chemical signature of the fire (indicated by the EC-Soil ratio) was elevated immediately after the fire and approached pre-burn levels by 24 MAB. Thus, the potential for wind erosion at the Jacob Fire site, as measured by the amount and type of emissions, increased significantly after the fire and returned to unburned levels by 24 MAB. The effect of fire on the potential for water erosion at the Jacob Fire site was more ambiguous. Runoff and sediment from ridge interspace soils and unburned interspace soils were similar throughout the study period. Seldom, if ever, did runoff and sediment occur in burned drainage area soils. For burned soils where runoff occurred at 1 MAB, the sediment size was finer than on unburned sites, but this effect disappeared by 3 MAB. For the three year study under the conditions tested at the Jacob Fire site, the potential for water erosion appeared relatively unaffected by the fire. Vegetation responses were documented for each year following the fire. By the end of the study, there was a substantial difference in plant densities and richness between drainage and ridge sites. Cheatgrass densities were higher in unburned plots, and cheatgrass was also more dominant in the community composition in unburned plots. Cheatgrass had increased in the burned area but so did other native species. Three years after the fire, the burned landscape continued to revegetate but had yet to approximate the condition of an unburned landscape. The results from the vegetation surveys support the wind erosion results, where the primary source of windborne particles originate from the understory, where lower plant diversity and densities were found. The soil appears to be more resilient and have a much shorter recovery time than the vegetation in this particular community.« less

Severe childhood burns in the Czech Republic: risk factors and prevention

PubMed Central

Čelko, Alexander Martin; Dáňová, Jana; Barss, Peter

2009-01-01

Abstract Objective To assess risk factors for paediatric burn injuries in the Czech Republic and to suggest preventive measures. Methods This study included all children aged 0–16 years hospitalized during 1993–2000 at the Prague Burn Centre and data from the Czech Ministry of Health on national paediatric burn hospitalizations during 1996–2006. Personal, equipment and environmental risk factors were identified from hospital records. Findings The incidence of burn admissions among 0–14 year-olds increased from 85 to 96 per 100 000 between 1996 and 2006, mainly due to a 13% increase among 1–4 year-olds. Between 1993–2000 and 2006, the proportion of burn victims in the country hospitalized at the Prague Burn Centre increased from 9% to 21%. Detailed data were available on 1064 children (64% boys). Around 31% of all burn hospitalizations were in 1 year-olds. Some 79% of burns occurred at home: 70% in the kitchen, 14% in the living room or bedroom and 11% in the bathroom. Of the 18% occurring outdoors, 80% involved boys. Scalds from hot liquids accounted for 70% of all burns. The mean hospital stay was 22 days for boys and 18 days for girls. Conclusion Most burns involved scalds from hot liquids at home: beverages in kitchens and water in bathrooms. There is a need for passive preventive measures, such as redesigned domestic cooking and eating areas, safer electrical kettles and temperature control devices for bathrooms. Educational programmes should be developed for parents and caregivers. A national plan for child burn prevention with specific targets would be helpful. PMID:19551256

The 1977 tundra fire in the Kokolik River area of Alaska

NASA Technical Reports Server (NTRS)

1981-01-01

Presumably caused by lightning, a large fire occurred due east of Point Lay several kilometers southwest of the Kokolik River, the farthest north a fire was ever fought by Bureau of Land Management personnel in Alaska. The progress and area extent of the fire were determined by analysis of LANDSAT MSS band 5 and 7 imagery. Low altitude observations from helicopter showed the fire burned a range of vegetation and relief types which included low polygonized and upland tussock tundras. The burned area appeared wetter on the surface than the unburned area, due to a lack of moisture absorbing organic matter and the possible release of moisture from the deeper thawed zone. Suggestions for future investigations of the effects of fire on tundra and permafrost terrains are discussed.

[Cutaneo-fascial flaps in restorative and reconstructive surgery of burns].

PubMed

Kurbanov, Sh I; Moroz, V Iu; Grishkevich, V M

1990-06-01

On the basis of experience with the treatment of more than 1,500 patients with post-burn defects, deformities, and trophic ulcers, the authors distinguished types of affection in which the traditional methods are ineffective. These 133 patients were subjected to plasty with ++cutaneo-fascial grafts; the zones of donor areas from which the grafts are taken are determined. Plasty with ++cutaneo-fascial grafts is indicated in defects of the face, deformity of the neck, total adduction contracture of the arm, defect of the breast, and affections of the hand, leg, and foot. Concrete grafts and the site from which they are taken for restoration of certain regions of the body are suggested. ++Cutaneo-fascial grafts make it possible to restore the shape, function, and the skin of the involved region.

Indicators of red squirrel (Tamiasciurus hudonicus) abundance in the whitebark pine zone

USGS Publications Warehouse

Mattson, D.J.; Reinhart, Daniel P.

1996-01-01

We investigated occupied squirrel middens and squirrel sightings and vocalizations as indicators of red squirrel (Tamiasciurus hudsonicus) abundance in the high-elevation whitebark pine (Pinus albicaulis) zone. Data were collected 1984-1989 from line transects located on 2 study sites in the Yellowstone ecosystem. We evaluated the performance of each measure on the basis of precision and biological considerations. We concluded that, of the 3 measures, active middens were the best indicator of red squirrel abundance. We also observed that the density of active middens dropped by 48%-66% between 1987 and 1989, following a severe drought and extensive wildfires that burned one of the study sites during 1988.

The effect of a changed environment on bacterial colonization rates in an established burns centre

PubMed Central

Wormald, P. J.

1970-01-01

In an established burns centre which moved from an old building to new purpose-designed premises, colonization rates of patients' burns with Staphylococcus aureus, Pseudomonas aeruginosa and other Gram-negative bacilli were not reduced. Colonization rates with Streptococcus pyogenes increased but the increase was mainly due to multiple importations in the new premises of a strain of higher communicability than any seen in the old. In the first 32 months in the new environment 10 patients were found colonized with pseudomonas on admission and 20 became colonized in the unit. A much higher proportion of patients with burns of more than 30% body surface became colonized than of patients with less. About one-third of the above 20 patients became colonized with strains already isolated from another patient; all but one of them had small area burns. Cross-infection was not observed from numerous heavily colonized patients with high percentage burns. This paradox is discussed in detail. Basin outflows in the new premises became colonized with P. aeruginosa of two serotypes not found on patients in this unit. PMID:4993291

The effect of a changed environment on bacterial colonization rates in an established burns centre.

PubMed

Wormald, P J

1970-12-01

In an established burns centre which moved from an old building to new purpose-designed premises, colonization rates of patients' burns with Staphylococcus aureus, Pseudomonas aeruginosa and other Gram-negative bacilli were not reduced. Colonization rates with Streptococcus pyogenes increased but the increase was mainly due to multiple importations in the new premises of a strain of higher communicability than any seen in the old.In the first 32 months in the new environment 10 patients were found colonized with pseudomonas on admission and 20 became colonized in the unit. A much higher proportion of patients with burns of more than 30% body surface became colonized than of patients with less. About one-third of the above 20 patients became colonized with strains already isolated from another patient; all but one of them had small area burns. Cross-infection was not observed from numerous heavily colonized patients with high percentage burns. This paradox is discussed in detail. Basin outflows in the new premises became colonized with P. aeruginosa of two serotypes not found on patients in this unit.

Investigations of ash fouling with cattle wastes as reburn fuel in a small-scale boiler burner under transient conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hyukjin Oh; Kalyan Annamalai; John M. Sweeten

2008-04-15

Fouling behavior under reburn conditions was investigated with cattle wastes (termed as feedlot biomass, FB) and coal as reburn fuels under a transient condition and short-time operation. A small-scale (30 kW or 100,000 Btu/hr) boiler burner research facility was used for the reburn experiments. The fuels considered for these experiments were natural gas (NG) for the ashless case, pure coal, pure FB, and blends of coal and FB. Two parameters that were used to characterize the ash 'fouling' were (1) the overall heat-transfer coefficient (OHTC) when burning NG and solid fuels as reburn fuels, and (2) the combustible loss throughmore » ash deposited on the surfaces of heat exchanger tubes and the bottom ash in the ash port. A new methodology is presented for determining ash fouling behavior under transient conditions. Results on the OHTCs for solid reburn fuels are compared with the OHTCs for NG. It was found that the growth of the layer of ash depositions over longer periods typically lowers OHTC, and the increased concentration of ash in gas phase promotes radiation in high-temperature zones during initial periods while decreasing the heat transfer in low-temperature zones. The ash analyses indicated that the bottom ash in the ash port contained a smaller percentage of combustibles with a higher FB percentage in the fuels, indicating better performance compared with coal because small particles in FB burn faster and the FB has higher volatile matter on a dry ash-free basis promoting more burn out. 16 refs., 12 figs., 6 tabs.« less

Histochemical study of alkali-burned rabbit anterior eye segment in which severe lesions were prevented by aprotinin treatment.

PubMed

Cejková, J; Lojda, Z; Salonen, E M; Vaheri, A

1989-01-01

Activities of different enzymes (acid glycosidases, phosphatases, Na+ - K+ -dependent ATPase, proteases, dehydrogenases) and acid glycosaminoglycans were studied by histochemical methods in sections of rabbit anterior eye segments after experimental alkali burn and treatment with aprotinin, an inhibitor of plasmin and other serine proteinases. Solutions of sodium hydroxide (0.25-1.0 M) were applied on corneas using 12-mm-diameter plastic tube for 15-60 s. After wiping with cotton and rinsing with tap water aprotinin solutions were applied in saline (in experimental animals) and saline (in control animals) dropwise in 12-h intervals for a month. Within the first two weeks aprotinin was used at a concentration of 5000 IU/ml. During the subsequent two weeks the aprotinin concentration was reduced to 2500 IU/ml. Striking differences in enzyme activities and in the healing between treated and untreated eyes were found. Without aprotinin, ulcers developed in most corneas within 3 weeks and plasmin was regularly demonstrated in tears and in the aqueous. When aprotinin treatment was started within 24 h after the burn, the number of enzymatically active inflammatory cells was significantly lower, not only in the cornea itself but also in the whole anterior eye segment. With aprotinin treatment no ulcerations and no plasmin in tears and the aqueous were observed and the corneas healed within a month. The healing process started from the zone of enzymatically activated corneal cells in the unburned zone at the corneal periphery. In the regenerating epithelium and endothelium high activities of Na+ -K+ -dependent ATPase, gamma-glutamyltransferase, lactate and succinate dehydrogenases appeared very soon.(ABSTRACT TRUNCATED AT 250 WORDS)

GLOBAL NON-SPHERICAL OSCILLATIONS IN THREE-DIMENSIONAL 4π SIMULATIONS OF THE H-INGESTION FLASH

DOE Office of Scientific and Technical Information (OSTI.GOV)

Herwig, Falk; Woodward, Paul R.; Lin, Pei-Hung

2014-09-01

We performed three-dimensional simulations of proton-rich material entrainment into {sup 12}C-rich He-shell flash convection and the subsequent H-ingestion flash that took place in the post-asymptotic giant branch star Sakurai's object. Observations of the transient nature and anomalous abundance features are available to validate our method and assumptions, with the aim of applying them to very low-metallicity stars in the future. We include nuclear energy feedback from H burning and cover the full 4π geometry of the shell. Runs on 768{sup 3} and 1536{sup 3} grids agree well with each other and have been followed for 1500 minutes and 1200 minutes.more » After an 850 minute long quiescent entrainment phase, the simulations enter into a global non-spherical oscillation that is launched and sustained by individual ignition events of H-rich fluid pockets. Fast circumferential flows collide at the antipode and cause the formation and localized ignition of the next H-overabundant pocket. The cycle repeats for more than a dozen times while its amplitude decreases. During the global oscillation, the entrainment rate increases temporarily by a factor of ≈100. Entrained entropy quenches convective motions in the upper layer until the burning of entrained H establishes a separate convection zone. The lower-resolution run hints at the possibility that another global oscillation, perhaps even more violent, will follow. The location of the H-burning convection zone agrees with a one-dimensional model in which the mixing efficiency is calibrated to reproduce the light curve. The simulations have been performed at the NSF Blue Waters supercomputer at NCSA.« less

r-process nucleosynthesis in dynamic helium-burning environments

NASA Technical Reports Server (NTRS)

Cowan, J. J.; Cameron, A. G. W.; Truran, J. W.

1985-01-01

The results of an extended examination of r-process nucleosynthesis in helium-burning enviroments are presented. Using newly calculated nuclear rates, dynamical r-process calculations have been made of thermal runaways in helium cores typical of low-mass stars and in the helium zones of stars undergoing supernova explosions. These calculations show that, for a sufficient flux of neutrons produced by the C-13 neutron source, r-process nuclei in solar proportions can be produced. The conditions required for r-process production are found to be 10 to the 20th-10 to the 21st neutrons per cubic centimeter for times of 0.01-0.1 s and neutron number densities in excess of 10 to the 19th per cubic centimeter for times of about 1 s. The amount of C-13 required is found to be exceedingly high - larger than is found to occur in any current stellar evolutionary model. It is thus unlikely that these helium-burning environments are responsible for producing the bulk of the r-process elements seen in the solar system.

On the combustion mechanisms of ZrH2 in double-base propellant.

PubMed

Yang, Yanjing; Zhao, Fengqi; Yuan, Zhifeng; Wang, Ying; An, Ting; Chen, Xueli; Xuan, Chunlei; Zhang, Jiankan

2017-12-13

Metal hydrides are regarded as a series of promising hydrogen-supplying fuel for solid rocket propellants. Their effects on the energetic and combustion performances of propellants are closely related to their reaction mechanisms. Here we report a first attempt to determine the reaction mechanism of ZrH 2 , a high-density metal hydride, in the combustion of a double-base propellant to evaluate its potential as a fuel. ZrH 2 is determined to possess good resistance to oxidation by nitrocellulose and nitroglycerine. Thus its combustion starts with dehydrogenation to generate H 2 and metallic Zr. Subsequently, the newly formed Zr and H 2 participate in the combustion and, especially, Zr melts and then combusts on the burning surface which favors the heat feedback to the propellant. This phenomenon is completely different from the combustion behavior of the traditional fuel Al, where the Al particles are ejected off the burning surface of the propellant to get into the luminous flame zone to burn. The findings in this work validate the potential of ZrH 2 as a hydrogen-supplying fuel for double-base propellants.

Multi-fuel combustor for gas turbine engines: Phase 1, Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Melconian, J.O.; Marden, W.W., III

An innovative can combustor configuration has been developed for gas turbine engines which has the potential of burning fuels ranging from gasoline to coal/water slurries at high efficiencies. The design is based on a Variable Residence Time (VRT) concept which allows large and agglomerated fuel particles adequate time to completely burn. High durability of the combustor is achieved by dual function use of the incoming air. For applications which require the burning of coal/water slurries, the design has the capability of removing the ash particles directly from the primary zone of the combustor. It is anticipated that because of themore » small size requirement of this combustor design, existing gas turbine engines could be retrofitted within the confines of the current engine envelope. In Phase 1, the feasibility of the concept was successfully demonstrated by three-dimensional mathematical modeling and water analogue tests. The Plexiglas model used in the water analogue tests was designed to fit the current production engine of a major manufacturer. 19 figs., 2 tabs.« less

Burn Injuries and Their Impact on Cognitive-Communication Skills in the Inpatient Rehabilitation Setting.

PubMed

Hendricks, Carla Tierney; Camara, Kristin; Violick Boole, Kathryn; Napoli, Maureen F; Goldstein, Richard; Ryan, Colleen M; Schneider, Jeffrey C

The prevalence and extent of cognitive-communication disorders and factors that have impact on outcomes are examined in the burn population within an inpatient rehabilitation facility. A retrospective data analysis was conducted on adults diagnosed with burn injury (n = 144). Descriptive statistics were used to identify the prevalence of cognitive-communication deficits on admission and discharge. The main outcomes were cognitive-communication ratings on discharge from inpatient rehabilitation as measured by the memory and problem-solving domains of the Functional Independence Measure (FIM) and composite score of the Functional Communication Measure (FCM). Medical, demographic and rehabilitation predictors of the main outcomes were assessed using regression analyses. On admission to inpatient rehabilitation, 79% of the total population presented with cognitive-communication impairments, and of them, 27% presented with persistent deficits on discharge. Admission FIM memory score, marital status, and age were significant predictors of discharge FIM memory score. Admission FIM problem-solving score, age, marital status, and prehospital living-with were significant predictors of discharge FIM problem-solving score. Admission FCM score and age were significant predictors of discharge FCM cognitive score. Persons with burn injuries are at risk for cognitive-communication impairments, which may persist after inpatient rehabilitation. FIM data obtained on admission can be used as a screening tool to identify these at-risk patients. Future work is needed to assess the efficacy of speech-language pathologist intervention for cognitive-communication deficits within the burn injury population.

Wound management and outcome of 595 electrical burns in a major burn center.

PubMed

Li, Haisheng; Tan, Jianglin; Zhou, Junyi; Yuan, Zhiqiang; Zhang, Jiaping; Peng, Yizhi; Wu, Jun; Luo, Gaoxing

2017-06-15

Electrical burns are important causes of trauma worldwide. This study aims to analyze the clinical characteristics, wound management, and outcome of electric burns. This retrospective study was performed at the Institute of Burn Research of the Third Military Medical University during 2013-2015. Data including the demographics, injury patterns, wound treatment, and outcomes were collected and analyzed. A total of 595 electrical burn patients (93.8% males) were included. The average age was 37.3 ± 14.6 y, and most patients (73.5%) were aged 19∼50 years. Most patients (67.2%) were injured in work-related circumstances. The mean total body surface area was 8.8 ± 11.8% and most wounds (63.5%) were full-thickness burns. Operation times of high-voltage burns and current burns were higher than those of low-voltage burns and arc burns, respectively. Of the 375 operated patients, 83.2% (n = 312) underwent skin autografting and 49.3% (n = 185) required skin flap coverage. Common types of skin flaps were adjacent (50.3%), random (42.2%), and pedicle (35.7%). Amputation was performed in 107 cases (18.0%) and concentrated on the hands (43.9%) and upper limbs (39.3%). The mean length of stay was 42.9 ± 46.3 d and only one death occurred (0.2%). Current burns and higher numbers of operations were major risk factors for amputation and length of stay, respectively. Electrical burns mainly affected adult males with occupational exposures in China. Skin autografts and various skin flaps were commonly used for electric burn wound management. More standardized and effective strategies of treatment and prevention are still needed to decrease amputation rates. Copyright © 2017 Elsevier Inc. All rights reserved.

Observations of biomass burning tracers in PM2.5 at two megacities in North China during 2014 APEC summit

NASA Astrophysics Data System (ADS)

Zhang, Zhisheng; Gao, Jian; Zhang, Leiming; Wang, Han; Tao, Jun; Qiu, Xionghui; Chai, Fahe; Li, Yang; Wang, Shulan

2017-11-01

To evaluate the effectiveness of biomass burning control measures on PM2.5 reduction, day- and nighttime PM2.5 samples were collected at two urban sites in North China, one in Beijing (BJ) and the other in Shijiazhuang (SJZ), during the 2014 Asia-Pacific Economic Cooperation (APEC) summit. Typical biomass burning aerosol tracers including levoglucosan (LG), Mannosan (MN), and water-soluble potassium (K+), together with other water-soluble ions and carbonaceous species were determined. The levels of biomass burning tracers dropped dramatically during the APEC period when open biomass burning activities were well controlled in North China, yet they increased sharply to even higher levels during the post-APEC period. Distinct linear regression relationships between LG and MN were found with lower LG/MN ratios from periods with much reduced open biomass burning activities. This was likely resulted from the reduced open crop residues burning and increased residential wood burning emissions, as was also supported by the simultaneous decrease in K+/LG ratio. The positive matrix factorization and air quality model simulation analyses suggested that PM2.5 concentration produced from biomass burning sources was reduced by 22% at BJ and 46% at SJZ during the APEC period compared to pre-APEC period, although they increased to higher levels after APEC mainly due to increased residential biomass burning emissions in winter heating season. Biomass burning was also found to be the most important contributor to carbonaceous species that might cause significant light extinction in this region. This study not only suggested implementing biomass burning controls measures were helpful to reduce PM2.5 in North China, but also pointed out both open crop residues burning and indoor biomass burning activities could make substantial contributions to PM2.5 and its major components in urban areas in North China.

Determination of biomass burning tracers in air samples by GC/MS

NASA Astrophysics Data System (ADS)

Janoszka, Katarzyna

2018-01-01

Levoglucosan (LG) as a main cellulose burning product at 300°C is a biomass burning tracer. LG characterize by relatively high molar mass and it is sorbed by particulate matter. In the study of air pollution monitoring LG is mainly analyzed in particulate matter, PM1 and PM2,5. The tracer create relatively high O-H…O bond and weaker C-H…O bond. Due to the hydrogen bond, LG dissolves very well in water. Analytical procedure of LG determination include: extraction, derivatization and analysis by gas chromatography coupled with mass spectrometry detector. In water samples levoglucosan is determined by liquid chromatography. The paper presents a methodology for particulate matter samples determination their analysis by gas chromatography coupled with a mass spectrometry detector. Determination of LG content in particulate matter was performed according to an analytical method based on simultaneous pyridine extraction and derivatization using N,O-bis (trimethylsilyl) trifluoroacetamide and trimethylchlorosilane mixture (BSTFA: TMCS, 99: 1).

Theoretical studies of massive stars. I - Evolution of a 15-solar-mass star from the zero-age main sequence to neon ignition

NASA Technical Reports Server (NTRS)

Endal, A. S.

1975-01-01

The evolution of a star with mass 15 times that of the sun from the zero-age main sequence to neon ignition has been computed by the Henyey method. The hydrogen-rich envelope and all shell sources were explicitly included in the models. An algorithm has been developed for approximating the results of carbon burning, including the branching ratio for the C-12 + C-12 reaction and taking some secondary reactions into account. Penetration of the convective envelope into the core is found to be unimportant during the stages covered by the models. Energy transfer from the carbon-burning shell to the core by degenerate electron conduction becomes important after the core carbon-burning stage. Neon ignition will occur in a semidegenerate core and will lead to a mild 'flash.' Detailed numerical results are given in an appendix. Continuation of the calculations into later stages and variations with the total mass of the star will be discussed in later papers.

The southwestern Maine fire area - four years later

Treesearch

Wayne G. Banks; Myron D. Ostrander

1952-01-01

In November 1951 the southwestern Maine area that burned in 1947 was re-studied to find out how the 130,000-acre forest fire affected the local economy, and to find out how well the forest land is being re-stocked.

What Is Sjögren's Syndrome?

MedlinePlus

... eyes. The main symptoms of Sjögren’s syndrome are dry eyes and dry mouth. Sjögren’s syndrome is an autoimmune ... What are the symptoms? The main symptoms are: Dry eyes. Your eyes may burn or itch or feel ...

Incompletely Mixed Surface Transient Storage Zones at River Restoration Structures: Modeling Implications

NASA Astrophysics Data System (ADS)

Endreny, T. A.; Robinson, J.

2012-12-01

River restoration structures, also known as river steering deflectors, are designed to reduce bank shear stress by generating wake zones between the bank and the constricted conveyance region. There is interest in characterizing the surface transient storage (STS) and associated biogeochemical processing in the STS zones around these structures to quantify the ecosystem benefits of river restoration. This research explored how the hydraulics around river restoration structures prohibits application of transient storage models designed for homogenous, completely mixed STS zones. We used slug and constant rate injections of a conservative tracer in a 3rd order river in Onondaga County, NY over the course of five experiments at varying flow regimes. Recovered breakthrough curves spanned a transect including the main channel and wake zone at a j-hook restoration structure. We noted divergent patterns of peak solute concentration and times within the wake zone regardless of transect location within the structure. Analysis reveals an inhomogeneous STS zone which is frequently still loading tracer after the main channel has peaked. The breakthrough curve loading patterns at the restoration structure violated the assumptions of simplified "random walk" 2 zone transient storage models which seek to identify representative STS zones and zone locations. Use of structure-scale Weiner filter based multi-rate mass transfer models to characterize STS zones residence times are similarly dependent on a representative zone location. Each 2 zone model assumes 1 zone is a completely mixed STS zone and the other a completely mixed main channel. Our research reveals limits to simple application of the recently developed 2 zone models, and raises important questions about the measurement scale necessary to identify critical STS properties at restoration sites. An explanation for the incompletely mixed STS zone may be the distinct hydraulics at restoration sites, including a constrained high velocity conveyance region closely abutting a wake zone that receives periodic disruption from the upstream structure shearing vortices.igure 1. River restoration j-hook with blue dye revealing main channel and edge of wake zone with multiple surface transient storage zones.

Local seismicity preceding the March 14, 1979, Petatlan, Mexico Earthquake (Ms = 7.6)

NASA Astrophysics Data System (ADS)

Hsu, Vindell; Gettrust, Joseph F.; Helsley, Charles E.; Berg, Eduard

1983-05-01

Local seismicity surrounding the epicenter of the March 14, 1979, Petatlan, Mexico earthquake was monitored by a network of portable seismographs of the Hawaii Institute of Geophysics from 6 weeks before to 4 weeks after the main shock. Prior to the main shock, the recorded local seismic activity was shallow and restricted within the continental plate above the Benioff zone. The relocated main shock hypocenter also lay above the Benioff zone, suggesting an initial failure within the continental lithosphere. Four zones can be recognized that showed relatively higher seismic activity than the background. Activity within these zones has followed a number of moderate earthquakes that occurred before or after the initial deployment of the network. Three of these moderate earthquakes were near the Mexican coastline and occurred sequentially from southeast to northwest during the three months before the Petatlan earthquake. The Petatlan event occurred along the northwestern extension of this trend. We infer a possible connection between this observed earthquake migration pattern and the subduction of a fracture zone because the 200-km segment that includes the aftershock zones of the Petatlan earthquake and the three preceding moderate earthquakes matches the intersection of the southeastern limb of the Orozco Fracture Zone and the Middle America Trench. The Petatlan earthquake source region includes the region of the last of the three near-coast seismic activities (zone A). Earthquakes of zone A migrated toward the Petatlan main shock epicenter and were separated from it by an aseismic zone about 10 km wide. We designate this group of earthquakes as the foreshocks of the Petatlan earthquake. These foreshocks occurred within the continental lithosphere and their observed characteristics are interpreted as due to the high-stress environment before the main shock. Pre-main shock seismicity of the Petatlan earthquake source region shows a good correlation with the aftershocks in their spatial distribution. This suggests that an asperity existing along the Benioff zone may have affected both the pre-main shock activity in the continental lithosphere and the aftershocks along the Benioff zone. Although major thrust earthquakes at trenches occur along Benioff zones, in the present study we find little activity on this interplate boundary before the Petatlan earthquake. The overlying continental block, on the contrary, is very active seismically. Our data suggest that the activity is probably governed by the stress transmitted from below due to coupling between two plates and the heterogeneity within the continental lithosphere. The continental material is probably the more likely place for precursors.

Burns due to acid assaults in Bogotá, Colombia.

PubMed

Guerrero, Linda

2013-08-01

Acid burns are not very frequent, occupying between 3% and maximum 14% of all etiologies. They mostly occur at home or at work, however there has been an increase in publications outlining chemical burns where aggression is the cause of this burn. There is a different epidemiological profile between developed countries and developing ones. It seems an ongoing upsurge is occurring in the number of registered attacks within developing countries in recent years. A cross sectional retrospective review of attacks by acid was done in Bogota, Colombia from 1995 to the first trimester 2012. A cumulative number of 35 burn patients were registered during the study period. It is found that the main target, almost the unique target, of this attack are young women belonging to low socioeconomic status with low education degree and high dependence on her partner. The patient's age mean was 22.7 years, ranging from 13 to 41 years. The physical and psychological scars were very severe. Copyright © 2012. Published by Elsevier Ltd.

Oral frostbite injury from intentional abuse of a fluorinated hydrocarbon.

PubMed

Kuspis, D A; Krenzelok, E P

1999-01-01

A serious but rarely reported complication of halogenated hydrocarbon inhalation abuse is severe mucosal frostbite. A 16-year-old male attempted to "get high" by inhaling airbrush propellant which contained 1,1-difluoroethane (CAS #75-376). The patient lost consciousness and upon awakening his lips and tongue were frozen. He suffered first- and second-degree burns of the larynx with vocal cord involvement and first-degree burns of the trachea, main stem bronchi, and esophagus. The oral cavity had second- and third-degree burns which required debridement. This case demonstrates the unusual but severe damage that can occur with the abuse of fluorinated hydrocarbons.

Pulverized coal fuel injector

DOEpatents

Rini, Michael J.; Towle, David P.

1992-01-01

A pulverized coal fuel injector contains an acceleration section to improve the uniformity of a coal-air mixture to be burned. An integral splitter is provided which divides the coal-air mixture into a number separate streams or jets, and a center body directs the streams at a controlled angle into the primary zone of a burner. The injector provides for flame shaping and the control of NO/NO.sub.2 formation.

Combustion and Heat Transfer Studies Utilizing Advanced Diagnostics: Combustion Studies

DTIC Science & Technology

1992-11-01

Research Zone With Combustion," Turbulent Shear Flows. VoL 5. pp. 337- and Development Center, Aero Propulsion and Power 346, Springer Verlg, New ...200 words) A long-term goal of the Air Force is to develop near-stoichiometric gas turbine combustors that will burn broad-specification fuels, and...laboratory combustors. Two novel methods for CARS slit function were developed ; these made possible precise and unambiguous measurements of flame

Computer-aided analysis of LANDSAT data for surveying Texas coastal zone environments. [Pass Cavallo and Port O'Conner

NASA Technical Reports Server (NTRS)

Kristof, S. J. (Principal Investigator); Weismiller, R. A.

1977-01-01

The author has identified the following significant results. The study areas were Pass Cavallo and Port O'Connor. The following terrestrial and aquatic environments were discriminated: alternating beach ridges, swales, sand dunes, beach birms, deflation surfaces, land-water interface, urban, spoil areas, fresh and salt water marshes, grass and woodland, recently burned or grazed areas, submerged vegetation, and waterways.

The effect of fire on habitat selection of mammalian herbivores: the role of body size and vegetation characteristics.

PubMed

Eby, Stephanie L; Anderson, T Michael; Mayemba, Emilian P; Ritchie, Mark E

2014-09-01

Given the role of fire in shaping ecosystems, especially grasslands and savannas, it is important to understand its broader impact on these systems. Post-fire stimulation of plant nutrients is thought to benefit grazing mammals and explain their preference for burned areas. However, fire also reduces vegetation height and increases visibility, thereby potentially reducing predation risk. Consequently, fire may be more beneficial to smaller herbivores, with higher nutritional needs and greater risks of predation. We tested the impacts of burning on different sized herbivores' habitat preference in Serengeti National Park, as mediated by burning's effects on vegetation height, live : dead biomass ratio and leaf nutrients. Burning caused a less than 4 month increase in leaf nitrogen (N), and leaf non-N nutrients [copper (Cu), potassium (K), and magnesium (Mg)] and a decrease in vegetation height and live : dead biomass. During this period, total herbivore counts were higher on burned areas. Generally, smaller herbivores preferred burned areas more strongly than larger herbivores. Unfortunately, it was not possible to determine the vegetation characteristics that explained burned area preference for each of the herbivore species observed. However, total herbivore abundance and impala (Aepyceros melampus) preference for burned areas was due to the increases in non-N nutrients caused by burning. These findings suggest that burned area attractiveness to herbivores is mainly driven by changes to forage quality and not potential decreases in predation risk caused by reductions in vegetation height. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

Nitric oxide formation in gas turbine engines: A theoretical and experimental study. Ph.D. Thesis - Nov. 1975. Final Report

NASA Technical Reports Server (NTRS)

Mikus, T.; Heywood, J. B.; Hicks, R. E.

1978-01-01

A modified Zeldovich kinetic scheme was used to predict nitric oxide formation in the burned gases. Nonuniformities in fuel-air ratio in the primary zone were accounted for by a distribution of fuel-air ratios. This was followed by one or more dilution zones in which a Monte Carlo calculation was employed to follow the mixing and dilution processes. Predictions of NOX emissions were compared with various available experimental data, and satisfactory agreement was achieved. In particular, the model is applied to the NASA swirl-can modular combustor. The operating characteristics of this combustor which can be inferred from the modeling predictions are described. Parametric studies are presented which examine the influence of the modeling parameters on the NOX emission level. A series of flow visualization experiments demonstrates the fuel droplet breakup and turbulent recirculation processes. A tracer experiment quantitatively follows the jets from the swirler as they move downstream and entrain surrounding gases. Techniques were developed for calculating both fuel-air ratio and degree of nonuniformity from measurements of CO2, CO, O2, and hydrocarbons. A burning experiment made use of these techniques to map out the flow field in terms of local equivalence ratio and mixture nonuniformity.

Post-fire interactions between soil water repellency, soil fertility and plant growth in soil collected from a burned piñon-juniper woodland

USGS Publications Warehouse

Fernelius, Kaitlynn J.; Madsen, Matthew D.; Hopkins, Bryan G.; Bansal, Sheel; Anderson, Val J.; Eggett, Dennis L.; Roundy, Bruce A.

2017-01-01

Woody plant encroachment can increase nutrient resources in the plant-mound zone. After a fire, this zone is often found to be water repellent. This study aimed to understand the effects of post-fire water repellency on soil water and inorganic nitrogen and their effects on plant growth of the introduced annual Bromus tectorum and native bunchgrass Pseudoroegneria spicata. Plots centered on burned Juniperus osteosperma trees were either left untreated or treated with surfactant to ameliorate water repellency. After two years, we excavated soil from the untreated and treated plots and placed it in zerotension lysimeter pots. In the greenhouse, half of the pots received an additional surfactant treatment. Pots were seeded separately with B. tectorum or P. spicata. Untreated soils had high runoff, decreased soilwater content, and elevated NO3eN in comparison to surfactant treated soils. The two plant species typically responded similar to the treatments. Above-ground biomass and microbial activity (estimated through soil CO2 gas emissions) was 16.8-fold and 9.5-fold higher in the surfactant-treated soils than repellent soils, respectably. This study demonstrates that water repellency can influence site recovery by decreasing soil water content, promoting inorganic N retention, and impairing plant growth and microbial activity.

Wildfire and aspect effects on hydrologic states after the 2010 Fourmile Canyon Fire

USGS Publications Warehouse

Ebel, Brian A.

2013-01-01

Wildfire can change how soils take in, store, and release water. This study examined differences in how burned and unburned plots on north versus south-facing slope aspects respond to rainfall. The largest wildfire impacts were litter/duff combustion on burned north-facing slopes versus soil-water retention reduction on burned south-facing slopes.Wildfire is one of the most significant disturbances in mountainous landscapes, affecting water supply and ecologic function and setting the stage for natural hazards such as flash floods. The impacts of wildfire can affect the entire hydrologic cycle. Measurements of soil-water content and matric potential in the near surface (top 30 cm) captured the hydrologic state in both burned and unburned hillslopes during the first spring through fall period (1 June–1 Oct. 2011) after the 2010 Fourmile Canyon Fire near Boulder, CO. This time span included different hydrologic periods characterized by cyclonic frontal storms (low-intensity, long duration), convective storms (high-intensity, short duration), and dry periods. In mountainous environments, aspect can also control hydrologic states, so north- vs. south-facing slopes were compared. Wildfire tended to homogenize soil-water contents across aspects and with depth in the soil, yet it also may have introduced an aspect control on matric potential that was not observed in unburned soils. Post-wildfire changes in hydrologic state were observed in south-facing soils, probably reflecting decreased soil-water retention after wildfire. North-facing soils were impacted the most, in terms of hydrologic state, by the loss of water storage in the combusted litter–duff layer and forest canopy, which had provided a large “hydrologic buffering” capacity when unburned. Unsaturated zone measurements showed increased variability in hydrologic states and more rapid state transitions in wildfire-impacted soils. A simple, qualitative analysis suggested that the range of unsaturated-zone processes along the gravity–capillarity–adsorption continuum was expanded by wildfire for a given soil. The small number of experimental plots in this study suggests that further work is needed before these conclusions can be generalized to other geographic areas.

Impact of obesity on body image dissatisfaction and social integration difficulty in adolescent and young adult burn injury survivors

PubMed Central

Chondronikola, Maria; Sidossis, Labros S.; Richardson, Lisa M.; Temple, Jeff R.; van den Berg, Patricia A.; Herndon, David N.; Meyer, Walter J.

2012-01-01

Objective Burn injury deformities and obesity have been associated with social integration difficulty and body image dissatisfaction. However, the combined effects of obesity and burn injury in social integration difficulty and body image dissatisfaction are unknown. Methods Adolescent and young adults burn injury survivors were categorized as normal weight (n=47) or overweight and obese (n=21). Burn-related and anthropometric information was obtained from patients' medical records, while validated questionnaires were used to assess the main outcomes and possible confounders. Analysis of covariance and multiple linear regressions were performed to evaluate the objectives of this study. Results Obese and overweight burn injury survivors did not experience increased body image dissatisfaction (12 ± 4.3 vs 13.1 ± 4.4, p = 0.57) or social integration difficulty (17.5 ± 6.9 vs 15.5 ± 5.7, p=0.16) compared to normal weight burn injury survivors. Weight status was not a significant predictor of social integration difficulty or body image dissatisfaction (p=0.19 and p=0.24, respectively). However, mobility limitations predicted greater social integration difficulty (p=0.005) and body image dissatisfaction (p<0.001), while higher weight status at burn was a borderline significant predictor of body image dissatisfaction (p=0.05). Conclusions Obese and overweight adolescents and young adults, who sustained a major burn injury as children, do not experience greater social integration difficulty and body image dissatisfaction compared to normal weight burn injury survivors. Mobility limitations and higher weight status at burn are likely more important factors affecting the long-term social integration difficulty and body image dissatisfaction of these young people. PMID:23292577

Epidemiology of pediatric burns and future prevention strategies-a study of 475 patients from a high-volume burn center in North India.

PubMed

Dhopte, Amol; Tiwari, V K; Patel, Pankaj; Bamal, Rahul

2017-01-01

Pediatric burns have a long-term social impact. This is more apparent in a developing country such as India, where their incidence and morbidity are high. The aim of this study was to provide recent prospective epidemiological data on pediatric burns in India and to suggest future preventive strategies. Children up to 18 years old admitted to the Department of Burns, Plastic & Maxillofacial Surgery, VMMC & Safdarjung Hospital, New Delhi, between January and December 2014 were included in the study. Data regarding age, sex, etiology, total body surface area (TBSA), circumstances of injury, and clinical assessment were collected. The Mann-Whitney test or Kruskal-Wallis test or ANOVA was used to compare involved TBSA among various cohort groups accordingly. Univariate and multivariate linear regression analyses were used to determine the predictors of TBSA. There were a total of 475 patients involved in the study, including seven suicidal burns, all of whom were females with a mean age greater than the cohort average. Age, type of burns, mode of injury, presence or absence of inhalation injury, gender, and time of year (quarter) for admission were found to independently affect the TBSA involved. Electrical burns also formed an important number of presenting burn patients, mainly involving teenagers. Several societal issues have come forth, e.g., child marriage, child labor, and likely psychological problems among female children as suggested by a high incidence of suicidal burns. This study also highlights several issues such as overcrowding, lack of awareness, dangerous cooking practices, and improper use of kerosene oil. There is an emergent need to recognize the problems, formulate strategies, spread awareness, and ban or replace hazardous substances responsible for most burn accidents.

Uncertainty analysis of moderate- versus coarse-scale satellite fire products for quantifying agricultural burning: Implications for Air Quality in European Russia, Belarus, and Lithuania

NASA Astrophysics Data System (ADS)

McCarty, J. L.; Krylov, A.; Prishchepov, A. V.; Banach, D. M.; Potapov, P.; Tyukavina, A.; Rukhovitch, D.; Koroleva, P.; Turubanova, S.; Romanenkov, V.

2015-12-01

Cropland and pasture burning are common agricultural management practices that negatively impact air quality at a local and regional scale, including contributing to short-lived climate pollutants (SLCPs). This research focuses on both cropland and pasture burning in European Russia, Lithuania, and Belarus. Burned area and fire detections were derived from 500 m and 1 km Moderate Resolution Imaging Spectroradiometer (MODIS), 30 m Landsat 7 Enhanced Thematic Mapper Plus (ETM+), and Landsat 8 Operational Land Imager (OLI) data. Carbon, particulate matter, volatile organic carbon (VOCs), and harmful air pollutants (HAPs) emissions were then calculated using MODIS and Landsat-based estimates of fire and land-cover and land-use. Agricultural burning in Belarus, Lithuania, and European Russia showed a strong and consistent seasonal geographic pattern from 2002 to 2012, with the majority of fire detections occurring in March - June and smaller peak in July and August. Over this 11-year period, there was a decrease in both cropland and pasture burning throughout this region. For Smolensk Oblast, a Russian administrative region with comparable agro-environmental conditions to Belarus and Lithuania, a detailed analysis of Landsat-based burned area estimations for croplands and pastures and field data collected in summer 2014 showed that the agricultural burning area can be up to 10 times higher than the 1 km MODIS active fire estimates. In general, European Russia is the main source of agricultural burning emissions compared to Lithuania and Belarus. On average, all cropland burning in European Russia as detected by the MCD45A1 MODIS Burned Area Product emitted 17.66 Gg of PM10 while annual burning of pasture in Smolensk Oblast, Russia as detected by Landsat burn scars emitted 494.85 Gg of PM10, a 96% difference. This highlights that quantifying the contribution of pasture burning and burned area versus cropland burning in agricultural regions is important for accurately calculating carbonaceous emissions and emissions that negatively impact air quality.

[Bibliometric analysis of scientific articles on rehabilitation nursing for adult burn patients in China].

PubMed

Ying, Sun; Jie, Cao; Ping, Feng; Lingjuan, Zhang

2015-06-01

To analyze the current research status of rehabilitation nursing for adult burn patients in China, and to disuss the related strategies. Chinese scientific articles on adult burn patients' rehabilitation nursing published from January 2003 to December 2013 were retrieved from 3 databases namely China Biology Medicine disc, Chinese Journals Full-text Database , and Chinese Science and Technology Journals Database . From the results retrieved, data with regard to publication year, journal distribution, research type, region of affiliation of the first author, and the main research content were collected. Data were processed with Microsoft Excel software. A total of 417 articles conforming with the criteria were retrieved. During the 11 years, the number of the relevant articles per year was on the rise, and the increasing rates in 2005, 2008, 2009, and 2013 were all above 30% . Regarding the distribution among journals, these 417 articles were published in 151 journals, with 188 articles in Source Journal for Chinese Scientific and Technical Papers , accounting for 45.08%. Regarding the research type, 173 out of the 417 articles were dealing with clinical experiences, accounting for 41.49% ; 172 out of the 417 articles were dealing with experimental studies, accounting for 41.25% . The regions of affiliation of the first author were mainly situated in Guangdong province, Shandong province, Hunan province, and Jiangsu province, with Guangdong province contributing 58 articles, accounting for 13.91%. The research content of these articles was mainly focused on psychological nursing, nursing model, and health education, respectively 188,101, and 85 articles, accounting for 45.08%, 24.22%, and 20.38%. The research on rehabilitation nursing for adult burn patients in China has been carried out nationwide. Although the number of relevant papers is on the rise, the quality of these papers needs to be further improved. There is an urgent need for the guideline on rehabilitation nursing for adult burn patients in China so as to standardize the content and procedure of rehabilitation nursing.

[Assessment of the use of racemic ketamine and its S(+) isomer, associated or not with low doses of fentanyl, in balneotherapy for major burn patients].

PubMed

Cantinho, Fernando Antônio de Freitas; Silva, Antonio Carlos Pereira da

2009-01-01

The care of the wounds of major burn patients triggers severe painful stimuli. The objective of this study was to assess the safety and efficacy of different drug combinations in anesthesia for balneotherapy. After approval by the Ethics Commission, 200 procedures of balneotherapy in 87 major burn adult patients were evaluated. Midazolam was used in all cases. The vials of ketamine were numbered and, therefore, at the time of the use, one did not know whether racemic or S(+)ketamine was being used. Each morning it was decided by drawing lots whether fentanyl would be used or not in the procedures of that day. Patients were included in one of four groups: ISO/sf (S(+) isomer without fentanyl), ISO/cf (S(+) isomer with fentanyl), RAC/sf (racemic ketamine without fentanyl), and RAC/cf (racemic ketamine with fentanyl). The initial doses proposed were as follows: midazolam, 0.06 mg.kg-1; ketamine, 1.0 to 1.1 mg.kg-1; and fentanyl, 0.8 (1/4)g.kg1-1; additional doses were administered as needed. Only one patient recalled the pain of balneotherapy. In the group that received S(+)ketamine, the use of fentanyl did not bring additional advantages; however, when associated with racemic ketamine, fentanyl reduced the total dose and the number of ketamine boluses. The extension of body surface burned was the main determinant of the severity of post-procedure pain. Reduced pain severity was the main factor considered by patients when grading their satisfaction with the anesthesia. The four different drug combinations proved to be safe and guaranteed the absence of pain during balneotherapy. Characteristics not directly related to the anesthetics proved to be more important in the incidence of post-procedure pain, which was the main factor considered by major burn patient to define their satisfaction with the anesthesia used.

Precordial skin burns after endoscopic submucosal dissection for gastric tube cancer.

PubMed

Miyagi, Motoshi; Yoshio, Toshiyuki; Hirasawa, Toshiaki; Ishiyama, Akiyoshi; Yamamoto, Yorimasa; Tsuchida, Tomohiro; Fujisaki, Junko; Igarashi, Masahiro

2015-11-01

Endoscopic submucosal dissection (ESD) is useful as a minimally invasive treatment option for early gastric cancer. ESD is also used in the management of postoperative remnant gastric cancers in the stomach and gastric tube cancers. Perforation and delayed bleeding have been the main complications of ESD reported in the management of gastric tube cancer. However, in the current literature, there is no description of precordial skin burns caused by electrical coagulation. While we treated 22 patients with gastric tube cancers by ESD from 2005 to 2014, we experienced five skin burns in four patients after ESD. We retrospectively analyzed clinical characteristics of precordial skin burn as a complication of ESD. All skin burns occurred in patients reconstructed using a presternal route, whose incidence of precordial skin burn was 55.6%. In all cases, lesions were located in the upper or middle third of gastric tubes irrespective of their direction. Skin burn developed on postoperative day (POD) 1 or POD 2, taking 4-7 days to heal and was accompanied by high fever in 60% of cases. The present study suggests that when carrying out ESD for gastric tube cancer using the presternal route, it is necessary to consider the occurrence of a precordial skin burn as a possible complication. © 2015 The Authors. Digestive Endoscopy © 2015 Japan Gastroenterological Endoscopy Society.

Acute kidney injury in critically burned patients resuscitated with a protocol that includes low doses of Hydroxyethyl Starch.

PubMed

Sánchez-Sánchez, M; Garcia-de-Lorenzo, A; Cachafeiro, L; Herrero, E; Asensio, M J; Agrifoglio, A; Flores, E; Estebanez, B; Extremera, P; Iglesias, C; Martinez, J R

2016-09-30

Acute kidney injury (AKI) is an important complication in burn patients. Recently, it has been recommended that hydroxyethyl starch (HES) be avoided in burn patients because it increases the incidence of AKI. Our purpose was to study incidence of AKI in critically ill burn patients resuscitated with Ringer's solution and supplements of HES. We conducted an observational study of 165 patients admitted to the critical care burn unit (with 30 ± 15% TBSA burned). The main outcome measures were incidence of AKI, contributions of colloids and crystalloids, various severity scores, comorbidities, complications and mortality. According to the RIFLE criteria, 10 (6.1%) patients presented with Risk, 11 (6.7%) presented with Injury and 11 (6.7%) presented with Failure. According to the AKIN criteria, 9.7% presented stage I, 3% stage II and 10.3% stage III. Replacement therapy (RRT) was performed in 15 patients (9.1%), but in 6 of them RRT was employed in the final stages of multi-organ failure. The incidence of AKI in severe burn patients is high according to the RIFLE or AKIN criteria and these patients experience more complications and higher mortality. Our study suggests that the use of HES in low doses in the burn resuscitation phase does not cause more AKI than resuscitation without HES, but further evaluation is required. Further studies should be conducted.

Tundra fire alters stream water chemistry and benthic invertebrate communities, North Slope, Alaska

NASA Astrophysics Data System (ADS)

Allen, A. R.; Bowden, W. B.; Kling, G. W.; Schuett, E.; Kostrzewski, J. M.; Kolden Abatzoglou, C.; Findlay, R. H.

2010-12-01

Increased fire frequency and severity are potentially important consequences of climate change in high latitude ecosystems. The 2007 Anaktuvuk River fire, which burned from July until October, is the largest recorded tundra fire from Alaska's north slope (≈1,000 km2). The immediate effects of wildfire on water chemistry and biotic assemblages in tundra streams are heretofore unknown. We hypothesized that a tundra fire would increase inorganic nutrient inputs to P-limited tundra streams, increasing primary production and altering benthic macroinvertebrate community structure. We examined linkages among: 1) percentage of riparian zone and overall watershed vegetation burned, 2) physical, chemical and biological stream characteristics, and 3) macroinvertebrate communities in streams draining burned and unburned watersheds during the summers of 2008 and 2009. Streams in burned watersheds contained higher mean concentrations of soluble reactive phosphorus (SRP), ammonium (NH4+), and dissolved organic carbon (DOC). In contrast, stream nitrate (NO3-) concentrations were lower in burned watersheds. The net result was that the tundra fire did not affect concentrations of dissolved inorganic nitrogen (NH4+ + NO3-). In spite of increased SRP, benthic chlorophyll-a biomass was not elevated. Macroinvertebrate abundances were 1.5 times higher in streams draining burned watersheds; Chironomidae midges, Nematodes, and Nemoura stoneflies showed the greatest increases in abundance. Multivariate multiple regression identified environmental parameters associated with the observed changes in the macroinvertebrate communities. Since we identified stream latitude as a significant predictor variable, latitude was included in the model as a covariate. After removing the variation associated with latitude, 67.3 % of the variance in macroinvertebrate community structure was explained by a subset of 7 predictor variables; DOC, conductivity, mean temperature, NO3-, mean discharge, SRP and NH4+. The percentage of riparian vegetation burned, the percentage of watershed vegetation burned and total suspended solids were not included in the model as these parameters correlated with DOC concentration at r > 0.90. These results indicate that tundra fire not only alters stream water chemistry, it also affects benthic macroinvertebrate community structure.

Burning mouth syndrome – a common dental problem in perimenopausal women

PubMed Central

Szponar, Elżbieta

2014-01-01

Burning mouth syndrome (BMS) is characterized by the presence of burning, paresthesia or pain of the oral mucosa in the absence of pathologic lesions revealed during the clinical examination. Moreover, the pain may be accompanied by oral dryness, hypersensitivity to some food compounds and taste disorders. Etiopathogenesis of this condition remains unclear. Potential local causative factors include among the others mechanical irritation, parafunctions and dysfunctions of the stomatognathic system, contact allergy to dental materials and electro-galvanic phenomena. Potential systemic causes include diabetes mellitus, B group vitamin deficiency (vitamins B1, B2, B6 and B12), folic acid and iron deficiency, hormonal imbalance, gastrointestinal diseases, psychiatric and neurological disorders and drug-induced side effects. The hypothesis concerning the role of hormonal changes in the development of BMS seems to be confirmed by a high incidence of this condition in perimenopausal women. Up to now, due to an unclear etiology of the disease, the treatment is very often ineffective and mainly symptomatic, which may exacerbate patient's anxiety and discomfort. In this paper we present the main etiologic factors of the burning mouth syndrome. We discuss the basic diagnostic and therapeutic methods and the influence of hormonal replacement therapy on the course of BMS based on the current medical reports. PMID:26327855

[Dynamics and combined injuries of main pest species in rice cropping zones of Yunnan, Southwest China].

PubMed

Dong, Kun; Dong, Yan; Wang, Hai-Long; Zhang, Li-Min; Zan, Qing-An; Chen, Bin; Li, Zheng-Yue

2014-01-01

A series of rice pest injuries (due to pathogens, insects, and weeds) were surveyed in 286 farmers' fields for major rice varieties of three rice cropping zones of Yunnan Province, Southwest China. The composition and dynamics of main pest species were analyzed, and the trend of rice pest succession in Yunnan was discussed based upon landmark publications. The results showed that the three rice cropping zones had different pest characteristics as regard to main species, dynamics and combined injuries. Sheath rot, bacterial leaf blight, rice stripe, leaf hoppers, armyworms and stem borers were serious in the japonica rice zone. Sheath blight and rice stripe were serious in the japonica-indica interlacing zone. Leaf blast, sheath blight, leaf folders and weeds above rice crop canopy were serious in the indica rice zone. False smut, plant hoppers and weeds below rice crop canopy were ubiquitous and serious in the three kinds of rice cropping zones. Many kinds of weed infestation emerged in the whole rice cropping seasons. Echinochloa crusgalli, Sagittaria pygmaea, Potamogeton distinctus and Spirodela polyrhiza were the main species of weeds in the rice cropping zones of Yunnan. Overall, levels of combined injuries due to pests in the japonica rice zone and the indica rice zone were higher than that in the japonica-indica interlacing zone. In terms of the trend of rice pest succession in Yunnan, injuries due to false smut, sheath blight and plant hoppers seemed to be in a worse tendency in all rice cropping zones of Yunnan, while dominants species of weeds in the paddy fields are shifting from the annual weeds to the perennial malignant weeds.

The relationship of marine stratus to synoptic conditions

NASA Technical Reports Server (NTRS)

Wylie, Donald P.; Hinton, Barry; Grimm, Peter; Kloesel, Kevin A.

1990-01-01

The marine stratus which persistently covered most of the eastern Pacific Ocean, had large clear areas during the FIRE Intensive Field Operations (IFO) in 1987. Clear zones formed inside the large oceanic cloud mass on almost every day during the IFO. The location and size of the clear zones varied from day to day implying that they were related to dynamic weather conditions and not to oceanic conditions. Forecasting of cloud cover for aircraft operations during the IFO was directed towards predicting when and where the clear and broken zones would form inside the large marine stratus cloud mass. The clear zones often formed to the northwest of the operations area and moved towards it. However, on some days the clear zones appeared to form during the day in the operations area as part of the diurnal cloud burn off. The movement of the clear zones from day to day were hard to follow because of the large diurnal changes in cloud cover. Clear and broken cloud zones formed during the day only to distort in shape and fill during the following night. The field forecasters exhibited some skill in predicting when the clear and broken cloud patterns would form in the operations area. They based their predictions on the analysis and simulations of the models run by NOAA's Numeric Meteorological Center. How the atmospheric conditions analyzed by one NOAA/NMC model related to the cloud cover is discussed.

Socioeconomic factors of smallholder farmers’ behavior in biomass burning around palm oil plantation in Indonesia

NASA Astrophysics Data System (ADS)

Maswadi; Arifudin; Septiana, Nurmelati; Maulidi

2018-03-01

Indonesian peatland fires has been revealed as the cause of haze disaster in Indonesia, while oil palm plantation’s concesion owned both by companies and smallholder farmers are accused as the main cause of this problem, especially in practice of land clearing. It is very important to conduct research on socioeconomic factors of farmers’ behavior in burning the peatland, while peatland one of the megabiomass storage in nature. The research was conducted in Kalimantan barat, where in province has been choosen two villages as the sample. Observation, interview with quiestionare, and focus group discussion were used in collecting data. In term of analysing the data, regression analysis (ordinary least square) was performed using SPSS Program. The result show that: (1). The socio economics factor that are affecting the burning behavior, were extension’s activities, degree of knowledge, consideration to burn, degree of participation on organisation and degree of cosmopolite. On the other hand, degree of burning frequent, was affected by land productivity, extension activities, and degree of participation in organisation, and finally the size of land’ burning is affected by, the kind of burning’s activities, the mutual aid (social capital), consideration of land burning, degree of awarness, and degree participation on organization.

Monitoring and treatment of coagulation abnormalities in burn patients. an international survey on current practices

PubMed Central

Lavrentieva, A.; Depetris, N.; Kaimakamis, E.; Berardino, M.; Stella, M.

2016-01-01

Summary The magnitude of coagulation abnormalities, and the definition and treatment of coagulopathy in burn patients are inadequately understood and continue to be discussed in the literature. We aimed to analyse physicians’ views on monitoring and treating coagulation abnormalities in burn patients. A total of 350 questionnaires were distributed electronically to burn ICU physicians. Participation was voluntary and anonymous. Responses were analysed electronically and comparisons were made according to the region of the ICU or the specialty of the physician. Of the 350 questionnaires distributed, 55 (15.7%) were returned. The majority of burn specialists consider sepsis-induced coagulopathy to be the most frequent coagulopathy in burn patients, and 74.5% declare that they do not use any specific definition/scoring system in their department to detect coagulopathy. The majority of specialists (70.8%) use standard coagulation tests. The most frequent indications for plasma transfusion are massive bleeding (32.8%) and Disseminated Intravascular Coagulation syndrome treatment (20%). The main specific factors reported in our study are cryoprecipitate (23.2%) and fibrinogen concentrate (18.9%). 21.1% of respondents state that they do not use any specific coagulation factor substitution in burn patients. Specific coagulation factor substitution is not a routine practice. The low response rate precludes the generalization of our results. PMID:28149244

Pre-hospital burn mission as a unique experience: a qualitative study.

PubMed

Froutan, Razieh; Khankeh, Hamid Reza; Fallahi, Masoud; Ahmadi, Fazlollah; Norouzi, Kian

2014-12-01

A thorough understanding of experiences related to pre-hospital emergency care of burns is a prerequisite of skill promotion for medical personnel. The aim of the present study was to evaluate the experiences of pre-hospital emergency personnel during burn accidents. The present qualitative study was performed using a content analysis method. In total, 18 Iranian emergency care personnel participated in the study. A purposeful sampling method was applied until reaching data saturation. Data were collected using semi-structured interviews and field observations. Afterwards, the gathered data were analyzed through face content analysis. By analyzing 498 primary codes, four main categories; the nature of burn care, tension at the accident scene, gradual job 'burnout', and insufficient information, were extracted from the experiences of pre-hospital emergency personnel during burn care. These categories each included several sub-categories, which were classified according to their significant characteristics. This study showed that different factors affect the quality of pre-hospital clinical services for burns. Authorities and health system administrators should consider the physical and psychological health of their staff, and assign policies to improve the quality of pre-hospital medical care. According to the present results, it is recommended that the process of pre-hospital emergency care for burns be investigated further. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

Effects of Pharmacological Interventions on Muscle Protein Synthesis and Breakdown in Recovery from Burns

PubMed Central

Diaz, Eva C.; Herndon, David N.; Porter, Craig; Sidossis, Labros S.; Suman, Oscar E.; Børsheim, Elisabet

2014-01-01

Objective The pathophysiological response to burn injury disturbs the balance between skeletal muscle protein synthesis and breakdown, resulting in severe muscle wasting. Muscle loss after burn injury is related to increased mortality and morbidity. Consequently, mitigation of this catabolic response has become a focus in the management of these patients. The aim of this review is to discuss the literature pertaining to pharmacological interventions aimed at attenuating skeletal muscle catabolism in severely burned patients. Data selection Review of the literature related to skeletal muscle protein metabolism following burn injury was conducted. Emphasis was on studies utilizing stable isotope tracer kinetics to assess the impact of pharmacological interventions on muscle protein metabolism in severely burned patients. Conclusion Data support the efficacy of testosterone, oxandrolone, human recombinant growth hormone, insulin, metformin, and propranolol in improving skeletal muscle protein net balance in patients with severe burns. The mechanisms underlying the improvement of protein net balance differ between types and dosages of drugs, but their main effect is on protein synthesis. Finally, the majority of studies have been conducted during the acute hypermetabolic phase of the injury. Except for oxandrolone, the effects of drugs on muscle protein kinetics following discharge from the hospital are largely unknown. PMID:25468473

Fire-related injuries with inpatient care in Finland: a 10-year nationwide study.

PubMed

Haikonen, Kari; Lillsunde, Pirjo M; Lunetta, Philippe; Lounamaa, Anne; Vuola, Jyrki

2013-06-01

The aim of this study was to examine fire-related injuries leading to inpatient care in Finland. The Finnish National Hospital Discharge Register (2000-2009) and a sample of 222 patients from the Helsinki Burn Centre who sustained flame burns was used. During the 10-years study period, the incidence of fire-related injuries with inpatient care was approximately 5.6 per 100000 persons-years (n=295; males 74%, females 26%). Approximately three quarters involved burns and the remaining cases were mostly combustion gas poisonings. Burns declined from 5.4 in 2000 to 4.0 per 100000 person-years in 2009. The decline was accounted for by young people primarily. Socio-economic features and smoking habits differ between the injured and general population. House fire victims were mainly middle aged and older, while injures involving flammable substances, campfires, etc., were mostly associated with young people. House fires caused the worst damage in terms of Total Body Surface Area burned and inhalation burns. Significantly more people die on the scene of the incident than during the hospital care. Targeting preventive measures in particular at older people and those with a tendency for alcohol abuse and smoking could potentially reduce the burden of the most severe flame burns. Copyright © 2012 Elsevier Ltd and ISBI. All rights reserved.

The Mauve Stinger Pelagia noctiluca (Forsskål, 1775). Distribution, Ecology, Toxicity and Epidemiology of Stings. A Review

PubMed Central

Mariottini, Gian Luigi; Giacco, Elisabetta; Pane, Luigi

2008-01-01

The toxicity of Cnidaria is a subject of concern due to its influence on humans. In particular, jellyfish blooms can highly affect human economical activities, such as bathing, fishery, tourism, etc., as well as the public health. Stinging structures of Cnidaria (nematocysts) produce remarkable effects on human skin, such as erythema, swelling, burning and vesicles, and at times further severe dermonecrotic, cardio- and neurotoxic effects, which are particularly dangerous in sensitive subjects. In several zones the toxicity of jellyfish is a very important health problem, thus it has stimulated the research on these organisms; to date toxicological research on Cnidarian venoms in the Mediterranean region is not well developed due to the weak poisonousness of venoms of jellyfish and anemones living in this area. In spite of this, during last decades several problems were also caused in the Mediterranean by stinging consequent to Cnidarian blooms mainly caused by Pelagia noctiluca (Forsskål, 1775) which is known to be the most venomous Mediterranean jellyfish. This paper reviews the knowledge on this jellyfish species, particularly considering its occurrence and toxicity. PMID:19005582

Poverty, population density, and the epidemiology of burns in young children from Mexico treated at a U.S. pediatric burn facility.

PubMed

Patel, Dipen D; Rosenberg, Marta; Rosenberg, Laura; Foncerrada, Guillermo; Andersen, Clark R; Capek, Karel D; Leal, Jesus; Lee, Jong O; Jimenez, Carlos; Branski, Ludwik; Meyer, Walter J; Herndon, David N

2018-08-01

Children 5 and younger are at risk for sustaining serious burn injuries. The causes of burns vary depending on demographic, cultural and socioeconomic variables. At this pediatric burn center we provided medical care to children from Mexico with severe injuries. The purpose of this study was to understand the impact of demographic distribution and modifiable risk factors of burns in young children to help guide prevention. A retrospective chart review was performed with children 5 and younger from Mexico who were injured from 2000-2013. The medical records of 447 acute patients were reviewed. Frequency counts and percentages were used to identify geographic distribution and calculate incidence of burns. Microsoft Powermap software was used to create a geographical map of Mexico based on types of burns. A binomial logistic regression was used to model the incidence of flame burns as opposed to scald burns in each state with relation to population density and poverty percentage. In all statistical tests, alpha=0.05 for a 95% level of confidence. Burns were primarily caused by flame and scald injuries. Admissions from flame injuries were mainly from explosions of propane tanks and gas lines and house fires. Flame injuries were predominantly from the states of Jalisco, Chihuahua, and Distrito Federal. Scalds were attributed to falling in large containers of hot water or food on the ground, and spills of hot liquids. Scald injuries were largely from the states of Oaxaca, Distrito Federal, and Hidalgo. The odds of a patient having flame burns were significantly associated with poverty percentage (p<0.0001) and population density (p=0.0085). Increasing levels of poverty led to decrease in odds of a flame burn, but an increase in the odds of scald burns. Similarly, we found that increasing population density led to a decrease in the odds of a flame burn, but an increase in the odds of a scald burn. Burns in young children from Mexico who received medical care at this pediatric burn center were attributed to flame and scalds. Potential demographic associations have been identified. Different states in Mexico have diverse cultural and socioeconomic variables that may influence the etiology of burns in young children and this information may help efficiently tailor burn prevention campaigns for burn prevention efforts in each region. This information will be used to develop and help modify existing prevention campaigns. Copyright © 2018 Elsevier Ltd and ISBI. All rights reserved.

EXPERIMENTAL INVESTIGATION OF PIC FORMATION IN ...

EPA Pesticide Factsheets

The report gives results of experiments to determine the effect of flame zone temperature on gas-phase flame formation and destruction of products of incomplete combustion (PICS) during dichlorodi-fluoromethane (CFC-12) incineration. The effect of water injection into the flame zone was also studied. Tests involved burning CFC-12 in a propane gas flame. Combustion gas samples were taken and analyzed for volatile organic compounds as well as polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/PCDF). CDD/PCDF were not detected at baseline operating conditions (1204 C and 9.3% CFC-12 by volume in fuel). Low levels of PCDD/ PCDF were detected in the combustion gas at a lower temperature (913 C). Poor combustion conditions producing smoke and soot may have contributed to the formation of PCDD/PCDF. Low levels of PCC/PCDF were also detected at the lower temperature with water injection into the flame zone. lame zone water injection may have a reducing effect on PCDD/PCDF formation during CFC-12 incineration. alogenated PICs (including chloromethane, vinyl chloride, CFC-11, dichloroethane, chloroform, trichloroethane, chlorobenzene, dichloropropene, carbon tetrachloride, methylene chloride, and tetrachloroethane) were detected during CFC-12 incineration. Information.

Kinetic calculations of explosives with slow-burning constituents

NASA Astrophysics Data System (ADS)

Howard, W. Michael; Souers, P. Clark; Fried, Laurence E.

1998-07-01

The equilibrium thermochemical code CHEETAH V1.40 has been modified to detonate part of the explosive and binder. An Einstein thermal description of the unreacted constituents is used, and the Einstein temperature may be increased to reduce heat absorption. We study the effect of the reactivity and thermal transport on the detonation velocity. Hydroxy-terminated-polybutadiene binders have low energy and density and would degrade the detonation velocity if they burned. Runs with unburned binder are closer to the measured values. Aluminum and ammonium perchlorate are also largely unburned within the sonic reaction zone that determines the detonation velocity. All three materials appear not to fully absorb heat as well. The normal assumption of total reaction in a thermochemical code is clearly not true for these special cases, where the detonation velocities have widely different values for different combinations of processes.

Comparison of global inventories of CO2 emissions from biomass burning during 2002-2011 derived from multiple satellite products.

PubMed

Shi, Yusheng; Matsunaga, Tsuneo; Saito, Makoto; Yamaguchi, Yasushi; Chen, Xuehong

2015-11-01

This study compared five widely used globally gridded biomass burning emissions inventories for the 2002-2011 period (Global Fire Emissions Database 3 (GFED3), Global Fire Emissions Database 4 (GFED4), Global Fire Assimilation System 1.0 (GFAS1.0), Fire INventory from NCAR 1.0 (FINN1.0) and Global Inventory for Chemistry-Climate studies-GFED4 (G-G)). Average annual CO2 emissions range from 6521.3 to 9661.5 Tg year(-1) for five inventories, with extensive amounts in Africa, South America and Southeast Asia. Coefficient of Variation for Southern America, Northern and Southern Africa are 30%, 39% and 48%. Globally, the majority of CO2 emissions are released from savanna burnings, followed by forest and cropland burnings. The largest differences among the five inventories are mainly attributable to the overestimation of CO2 emissions by FINN1.0 in Southeast Asia savanna and cropland burning, and underestimation in Southern Africa savanna and Amazon forest burning. The overestimation in Africa by G-G also contributes to the differences. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Catalytic combustion of residual fuels

NASA Technical Reports Server (NTRS)

Bulzan, D. L.; Tacina, R. R.

1981-01-01

A noble metal catalytic reactor was tested using two grades of petroleum derived residual fuels at specified inlet air temperatures, pressures, and reference velocities. Combustion efficiencies greater than 99.5 percent were obtained. Steady state operation of the catalytic reactor required inlet air temperatures of at least 800 K. At lower inlet air temperatures, upstream burning in the premixing zone occurred which was probably caused by fuel deposition and accumulation on the premixing zone walls. Increasing the inlet air temperature prevented this occurrence. Both residual fuels contained about 0.5 percent nitrogen by weight. NO sub x emissions ranged from 50 to 110 ppm by volume at 15 percent excess O2. Conversion of fuel-bound nitrogen to NO sub x ranged from 25 to 50 percent.

The bacteriological profile of the burned patients in the center of burns in CHU Mohamed VI Marrakech (about 123 cases)

PubMed Central

Benchamkha, Yassine; Dhaidah, Ouafaa; Dahazze, Adil; Meriem, Quaboul; Elamrani, Moulay Driss; Ettalbi, Salwa

2017-01-01

The bacterial nosocomial infection is one of the leading causes of morbidity and mortality for burned patient; we conducted a retrospective study of 123 patients hospitalized in the burns center CHUMED VI of Marrakechover a period of 3 years, from January 1st, 2013 to December 31st, 2016. The criteria for nosocomial infection were those of the Center for Disease Control in Atlanta in 1988. Incidence rates were calculated. The bacterial ecology of the department was described as also antibiotype. The predominancy of the population was male. The cumulative incidence was 103 infections per 1000 days of treatment. Regarding the characteristics of bacterial infections, infected sites were skin (69%), blood (18%), urinary tract (12%) and lungs (1%). The main organisms were: Staphylococcus sp. (37.7%), Pseudomonas aeruginosa (19.8%), Enterococcus faecalis and Proteus mirabilis (18.5%). Staphylococci were resistant méticillo-in 22% of cases. Pseudomonas and Acinetobacter were multi-resistant (66%). The establishment of the bacterial ecology of the service, helped us set the right rules of prescription of antibiotics, which was based on the infected site, the type of organism, its sensitivity, the molecule used and the pharmacokinetics particular patient burned. The two main organisms being Staphylococcus and Pseudomonas aeruginosa, antibiotics used in the Service will then beta-lactams, glycopeptides, fluoroquinolones and aminoglycosides. Finally, to control the epidemic risk posed by the emergence of resistant organisms is necessary to combine the practice of good antibiotic therapy and prevention. PMID:29119059

The NAv1.7 blocker protoxin II reduces burn injury-induced spinal nociceptive processing.

PubMed

Torres-Pérez, Jose Vicente; Adamek, Pavel; Palecek, Jiri; Vizcaychipi, Marcela; Nagy, Istvan; Varga, Angelika

2018-01-01

Controlling pain in burn-injured patients poses a major clinical challenge. Recent findings suggest that reducing the activity of the voltage-gated sodium channel Na v 1.7 in primary sensory neurons could provide improved pain control in burn-injured patients. Here, we report that partial thickness scalding-type burn injury on the rat paw upregulates Na v 1.7 expression in primary sensory neurons 3 h following injury. The injury also induces upregulation in phosphorylated cyclic adenosine monophosphate response element-binding protein (p-CREB), a marker for nociceptive activation in primary sensory neurons. The upregulation in p-CREB occurs mainly in Na v 1.7-immunopositive neurons and exhibits a peak at 5 min and, following a decline at 30 min, a gradual increase from 1 h post-injury. The Na v 1.7 blocker protoxin II (ProTxII) or morphine injected intraperitoneally 15 min before or after the injury significantly reduces burn injury-induced spinal upregulation in phosphorylated serine 10 in histone H3 and phosphorylated extracellular signal-regulated kinase 1/2, which are both markers for spinal nociceptive processing. Further, ProTxII significantly reduces the frequency of spontaneous excitatory post-synaptic currents in spinal dorsal horn neurons following burn injury. Together, these findings indicate that using Na v 1.7 blockers should be considered to control pain in burn injury. • Burn injury upregulates Na v 1.7 expression in primary sensory neurons. • Burn injury results in increased activity of Na v 1.7-expressing primary sensory neurons. • Inhibiting Na v 1.7 by protoxin II reduces spinal nociceptive processing. • Na v 1.7 represents a potential target to reduce pain in burn injury.

Risk of hospitalization for fire-related burns during extreme cold weather.

PubMed

Ayoub, Aimina; Kosatsky, Tom; Smargiassi, Audrey; Bilodeau-Bertrand, Marianne; Auger, Nathalie

2017-10-01

Environmental factors are important predictors of fires, but no study has examined the association between outdoor temperature and fire-related burn injuries. We sought to investigate the relationship between extremely cold outdoor temperatures and the risk of hospitalization for fire-related burns. We carried out a time-stratified case-crossover study of 2470 patients hospitalized for fire-related burn injuries during cold months between 1989 and 2014 in Quebec, Canada. The main exposure was the minimum outdoor temperature on the day of and the day before the burn. We computed odds ratios (OR) and 95% confidence intervals (CI) to evaluate the relationship between minimum temperature and fire-related burns, and assessed how associations varied across sex and age. Exposure to extreme cold temperature was associated with a significantly higher risk of hospitalization for fire-related burns. Compared with 0°C, exposure to a minimum temperature of -30°C was associated with an OR of 1.51 (95% CI 1.22-1.87) for hospitalization for fire-related burns. The associations were somewhat stronger for women, youth, and the elderly. Compared with 0°C, a minimum temperature of -30°C was associated with an OR for fire-related burn hospitalization of 1.65 for women (95% CI 1.13-2.40), 1.60 for age < 25 years (95% CI 1.02-2.52), and 1.73 for age ≥ 65 years (95% CI 1.08-2.77). Extremely cold outdoor temperature is a risk factor for fire-related burns. Measures to prevent fires should be implemented prior to the winter season, and enhanced during extreme cold. Copyright © 2017 Elsevier Inc. All rights reserved.

Addendum to High Pressure Burn Rate Measurements on an Ammonium Perchlorate Propellant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Glascoe, E A; Tan, N

2010-11-08

As part of a small follow-on study, the burn rate of the ammonium perchlorate (AP) based material TAL-1503 was studied at a relatively mild pressure. The goal of this final experiment was to burn TAL-1503 at the lowest pressures possible using the LLNL High Pressure Strand Burner (LLNL-HPSB). The following is a description of the experiment and the results with a brief discussion of data and a comparison to the higher pressure data. This is not meant to be a stand-alone report and readers should refer to the main report for experimental details and discussion. High pressure deflagration rate measurementsmore » of a unique AP/HTPB based material (TAL-1503) were performed using the LLNL high pressure strand burner apparatus. The material burns in a well behaved, laminar fashion between 20 and 300 MPa with a burn law of B = (0.6 {+-} 0.1) x P{sup (1.05{+-}0.02)} that was calculated based on the best data available from the experiments. In the pressure range of 2 and 10 MPa the material burned laminarly with a burn law of B = (2.0 {+-} 0.2) x P{sup (0.66{+-}0.05)}. In these results, B is the burn rate in mm/s and P is the pressure in units of MPa. Comparison of the TAL-1503 results with similar propellants that contain micrometer sized aluminum indicate that the burn rates are relatively unaffected by the aluminum. However, the pressure change is significantly larger when aluminum is present, most likely due to the high temperatures achieved from burning aluminum.« less

β-Adrenergic blockade does not impair the skin blood flow sensitivity to local heating in burned and nonburned skin under neutral and hot environments in children.

PubMed

Rivas, Eric; McEntire, Serina J; Herndon, David N; Mlcak, Ronald P; Suman, Oscar E

2017-05-01

We tested the hypothesis that propranolol, a drug given to burn patients to reduce hypermetabolism/cardiac stress, may inhibit heat dissipation by changing the sensitivity of skin blood flow (SkBF) to local heating under neutral and hot conditions. In a randomized double-blind study, a placebo was given to eight burned children, while propranolol was given to 13 burned children with similar characteristics (mean±SD: 11.9±3 years, 147±20 cm, 45±23 kg, 56±12% Total body surface area burned). Nonburned children (n=13, 11.4±3 years, 152±15 cm, 52±13 kg) served as healthy controls. A progressive local heating protocol characterized SkBF responses in burned and unburned skin and nonburned control skin under the two environmental conditions (23 and 34°C) via laser Doppler flowmetry. Resting SkBF was greater in burned and unburned skin compared to the nonburned control (main effect: skin, P<.0001; 57±32 burned; 38±36 unburned vs 9±8 control %SkBF max ). No difference was found for maximal SkBF capacity to local heating between groups. Additionally, dose-response curves for the sensitivity of SkBF to local heating were not different among burned or unburned skin, and nonburned control skin (EC 50 , P>.05) under either condition. Therapeutic propranolol does not negatively affect SkBF under neutral or hot environmental conditions and further compromise temperature regulation in burned children. © 2017 John Wiley & Sons Ltd.

First aid practices, beliefs, and sources of information among caregivers regarding paediatric burn injuries in Harare, Zimbabwe: A cross-sectional study.

PubMed

Chirongoma, Farai; Chengetanai, Samson; Tadyanemhandu, Cathrine

2017-06-01

While burns take seconds to occur, injuries incurred result in pain and undesirable long term effects that might take a lifetime to overcome. The study was carried out to determine the measures of first aid delivered by caregivers after a burn injury and sources of the information. A cross- sectional study was carried out over a period of 3 months at two central hospitals in Harare. A questionnaire was administered to the caregivers of children within the age group of 0-60 months admitted in burns wards to elicit information on the circumstances of the burn injury and the first aid methods which were administered. Out of the 50 children who were recruited, 54.0% were females and the mean age was 29.5 months (SD= 15.5). After the burn injury 30(60.0%) of the caregivers, cooled the burn injury with cold running water whilst some caregivers also applied eggs, margarine and some traditional herbs as first aid. The other practices reported by the caregivers included use of urine and crushed cockroaches after burn injury in 40 (80.0%) whilst 20 (40.0%) reported used aloe vera gel after a burn injury. About half of the caregivers got first aid information mainly from family members and very few indicated that the information was obtained from mass media, 3 (6.0%). The first aid measures used by the majority of caregivers were either incomplete or inadequate. Although some caregivers had adequate knowledge of what to do after an injury, there still was widespread use of alternatives therapies in burn management.

Two-year hospital records of burns from a referral center in Western Iran: March 2010-March 2012.

PubMed

Ahmadijouybari, Touraj; Najafi, Farid; Moradinazar, Mehdi; Karami-matin, Behzad; Karami-matin, Reza; Ataie, Maria; Hatami, Masoumeh; Purghorbani, Samira; Amee, Vahid

2014-01-01

Burns are among the most common injuries affecting a great number of people worldwide annually. In Iran, especially in its western region and in Kermanshah province, burns have a relatively high incidence. The present study was aimed at investigating epidemiological characteristics in Western Iran. Within a cross-sectional study, the data on all patients attending the Burns Center at Imam Khomeini Hospital (Kermanshah, Iran) during 2010-2011 and 2011-2012 (24 months) were collected. Then, age, gender, cause of burns, total body surface area, and time of the occurrence were extracted from the hospital records. The data were analyzed using the SPSS statistical package (Version 19, for Windows). We used chi-squared test when we compared the categorical responses between two or more groups. For comparing means between two groups we used t-test. In addition, trends were investigated using linear regression. Overall 13,248 people were referred to the Burns Center at Imam Khomeini Hospital (Kermanshah, Iran) during the period of study, including 328 cases of self-immolation. The mean age of the patients was 27±19 years and 29±13 years for unintentional burns and self-immolation respectively. Out of the total number of unintentional cases, 6,519 (50.5%) were men, while the corresponding percentage of men among the self-immolation cases was 16.6% (p less than 0.001). Trends in the number of cases were cyclic, with the highest and lowest number of burns cases being in March and May. Overall, hot liquids and flammable materials were the two most important causes of unintentional burns. However, flammable materials were the main cause of burns among self-immolation cases. During hospital admission, 168 (51%) self-immolation victims and 43 (0.33%) unintentional burn victims died. While major preventive measures are not adequately used in developing countries, burns and their burden can be significantly reduced by increasing public awareness and by applying simple preventive measures. © 2014 KUMS, All rights reserved.

Fire hazard after prescribed burning in a gorse shrubland: implications for fuel management.

PubMed

Marino, Eva; Guijarro, Mercedes; Hernando, Carmen; Madrigal, Javier; Díez, Carmen

2011-03-01

Prescribed burning is commonly used to prevent accumulation of biomass in fire-prone shrubland in NW Spain. However, there is a lack of knowledge about the efficacy of the technique in reducing fire hazard in these ecosystems. Fire hazard in burned shrubland areas will depend on the initial capacity of woody vegetation to recover and on the fine ground fuels existing after fire. To explore the effect that time since burning has on fire hazard, experimental tests were performed with two fuel complexes (fine ground fuels and regenerated shrubs) resulting from previous prescribed burnings conducted in a gorse shrubland (Ulex europaeus L.) one, three and five years earlier. A point-ignition source was used in burning experiments to assess ignition and initial propagation success separately for each fuel complex. The effect of wind speed was also studied for shrub fuels, and several flammability parameters were measured. Results showed that both ignition and initial propagation success of fine ground fuels mainly depended on fuel depth and were independent of time since burning, although flammability parameters indicated higher fire hazard three years after burning. In contrast, time since burning increased ignition and initial propagation success of regenerated shrub fuels, as well as the flammability parameters assessed, but wind speed had no significant effect. The combination of results of fire hazard for fine ground fuels and regenerated shrubs according to the variation in relative coverage of each fuel type after prescribed burning enabled an assessment of integrated fire hazard in treated areas. The present results suggest that prescribed burning is a very effective technique to reduce fire hazard in the study area, but that fire hazard will be significantly increased by the third year after burning. These results are valuable for fire prevention and fuel management planning in gorse shrubland areas. Copyright © 2010 Elsevier Ltd. All rights reserved.

AUTOMATIC RECORDING OF THE RADIOACTIVITY OF ZONES ELUTED FROM THE GAS- LIQUID CHROMATOGRAM

DOE Office of Scientific and Technical Information (OSTI.GOV)

James, A.T.; Piper, E.A.

1961-03-01

A simple proportional flow counter for use with the gas chromatogram is described. which is operated at room temperature by burning all eluted material to CO/sub 2/ over heated copper oxide. The gas stream is dried. 5% CO/sub 2/ is injected and the mixture passed into the counter. Details are given of the necessary circuitry. Examples are provided of its use with long chain fatty acids. (auth)

Risk factors for childhood burns: a case-control study of Ghanaian children.

PubMed Central

Forjuoh, S N; Guyer, B; Strobino, D M; Keyl, P M; Diener-West, M; Smith, G S

1995-01-01

STUDY OBJECTIVE--To study risk factors for childhood burns in order to identify possible preventive strategies. DESIGN--Case-control design with pair matching of controls to cases in relation to age, sex, and area of residence. The cases and controls were identified by a community based, multisite survey. The effects of host and socioenvironmental variables reported by mothers were investigated in a multivariate analysis using conditional logistic regression. SETTING--A developing country setting the Ashanti Region in Ghana. PARTICIPANTS--These comprised 610 cases aged 0-5 years who had been burned (as evidenced by a visible scar) and 610 controls with no burn history. MAIN RESULTS--The presence of a pre-existing impairment in a child was the strongest risk factor in this population (OR = 6.71; 95% CI 2.78, 16.16). Other significant risk factor included: sibling death from a burn (OR = 4.41; 95% CI 1.16, 16.68); history of burn in a sibling (OR = 1.79; 95% CI 1.24, 2.58); and storage of a flammable substance in the home (OR = 1.51; 95% CI 1.03; 2.21). Maternal education had a protective effect against childhood burns, although this effect was not strong (OR = 0.76; 95% CI 0.55, 1.05). CONCLUSIONS--Community programmes to ensure adequate child supervision and general child wellbeing, particularly for those with impairments, as well as parental education about burns are recommended, to reduce childhood burns in this region of Ghana. The public should bed advised against storing flammable substances in the home. PMID:7798049

Hydrofluoric acid burn resulting from ignition of gas from a compressed air duster.

PubMed

Foster, Kevin N; Jones, LouAnn; Caruso, Daniel M

2003-01-01

A young female suffered burns to her hand after the ignition of gas from a compressed air duster. After debridement and dressing, the patient continued to have pain out of proportion to injury that was refractory to intravenous morphine. The material safety data sheet revealed that the chemical used was 1,1-difluoroethane. High temperatures can cause decompensation to form hydrofluoric acid. Calcium gluconate gel was applied topically to the patient's burns, which caused prompt and complete relief of her pain. A review of different compressed air duster products revealed that the main ingredient in each was a halogenated hydrocarbon. Although not considered flammable, all products have warnings regarding the possibility of ignition under various circumstances. Ignition of the gas in compressed air cleaners not only can cause flame burns, it can also cause chemical damage from exposure to hydrogen and fluoride ions. Prompt recognition and treatment is necessary to prevent severe injury.

Steroid dysregulation and stomatodynia (burning mouth syndrome).

PubMed

Woda, Alain; Dao, Thuan; Gremeau-Richard, Christelle

2009-01-01

Stomatodynia ( burning mouth syndrome) is characterized by a spontaneous, continuous burning pain felt in the oral mucosa typically of anxiodepressive menopausal women. Because there is no obvious organic cause, it is considered a nonspecific pain. This Focus Article proposes a hypothesis based on the following pathophysiological cascade: chronic anxiety or post traumatic stress leads to a dysregulation of the adrenal production of steroids. One consequence is a decreased or modified production of some major precursors for the neuroactive steroid synthesis occurring in the skin, mucosa, and nervous system. At menopause, the drastic fall of the other main precursor supply , the gonadal steroids, leads to a brisk alteration of the production of neuroactive steroids. This results in neurodegenerative alterations of small nerves fibers of the oral mucosa and /or some brain areas involved in oral somatic sensations. These neuropathic changes become irreversible and precipitate the burning pain, dysgeusia, and xerostomia associated with stomatodynia, which all involve thin nerve fibers.

A rare chemical burn due to Ranunculus arvensis: three case reports.

PubMed

Kocak, Abdullah O; Saritemur, Murat; Atac, Kenan; Guclu, Sibel; Ozlu, Ibrahim

2016-01-01

Ranunculus arvensis, a plant that is a member of Ranunculaceae family, generally used for local treatment of joint pain, muscle pain, burns, lacerations, edema, abscess drainage, hemorrhoids, and warts among the population. In this case report, we presented three patients who developed chemical skin burns after using R. arvensis plant locally for knee pain. The destructive effect of the plant has been reported previously to be more in fresh plants and less in dried plants. Although protoanemonin, which is considered as the main toxic substance, was reported to be absent in dried or boiled plants, the plant was boiled, cooled, and wrapped over the region with pain in our cases. Therefore, we thought that protoanemonin may be considered to be heat resistant. Also, the burn management proceeded up to surgery by using the flap technique in one of our patients in contrast to the cases found in published reports who were treated by antibiotics and dressings.

Modeling of fire smoke movement in multizone garments building using two open source platforms

NASA Astrophysics Data System (ADS)

Khandoker, Md. Arifur Rahman; Galib, Musanna; Islam, Adnan; Rahman, Md. Ashiqur

2017-06-01

Casualty of garment factory workers from factory fire in Bangladesh is a recurring tragedy. Smoke, which is more fatal than fire itself, often propagates through different pathways from lower to upper floors during building fire. Among the toxic gases produced from a building fire, carbon monoxide (CO) can be deadly, even in small amounts. This paper models the propagation and transportation of fire induced smoke (CO) that resulted from the burning of synthetic polyester fibers using two open source platforms, CONTAM and Fire Dynamics Simulator (FDS). Smoke migration in a generic multistoried garment factory building in Bangladesh is modeled using CONTAM where each floor is compartmentalized by different zones. The elevator and stairway shafts are modeled by phantom zones to simulate contaminant (CO) transport from one floor to upper floors. FDS analysis involves burning of two different stacks of polyester jacket of six feet height and with a maximum heat release rate per unit area of 1500kw/m2 over a storage area 50m2 and 150m2, respectively. The resulting CO generation and removal rates from FDS are used in CONTAM to predict fire-borne CO propagation in different zones of the garment building. Findings of the study exhibit that the contaminant flow rate is a strong function of the position of building geometry, location of initiation of fire, amount of burnt material, presence of AHU and contaminant generation and removal rate of CO from the source location etc. The transport of fire-smoke in the building Hallways, stairways and lifts are also investigated in detail to examine the safe egress of the occupants in case of fire.

Postfire logging in riparian areas.

PubMed

Reeves, Gordon H; Bisson, Peter A; Rieman, Bruce E; Benda, Lee E

2006-08-01

We reviewed the behavior of wildfire in riparian zones, primarily in the western United States, and the potential ecological consequences of postfire logging. Fire behavior in riparian zones is complex, but many aquatic and riparian organisms exhibit a suite of adaptations that allow relatively rapid recovery after fire. Unless constrained by other factors, fish tend to rebound relatively quickly, usually within a decade after a wildfire. Additionally, fire and subsequent erosion events contribute wood and coarse sediment that can create and maintain productive aquatic habitats over time. The potential effects of postfire logging in riparian areas depend on the landscape context and disturbance history of a site; however available evidence suggests two key management implications: (1) fire in riparian areas creates conditions that may not require intervention to sustain the long-term productivity of the aquatic network and (2) protection of burned riparian areas gives priority to what is left rather than what is removed. Research is needed to determine how postfire logging in riparian areas has affected the spread of invasive species and the vulnerability of upland forests to insect and disease outbreaks and how postfire logging will affect the frequency and behavior of future fires. The effectiveness of using postfire logging to restore desired riparian structure and function is therefore unproven, but such projects are gaining interest with the departure of forest conditions from those that existed prior to timber harvest, fire suppression, and climate change. In the absence of reliable information about the potential consequence of postfire timber harvest, we conclude that providing postfire riparian zones with the same environmental protections they received before they burned isjustified ecologically Without a commitment to monitor management experiments, the effects of postfire riparian logging will remain unknown and highly contentious.

Diagnosing Tibetan pollutant sources via volatile organic compound observations

NASA Astrophysics Data System (ADS)

Li, Hongyan; He, Qiusheng; Song, Qi; Chen, Laiguo; Song, Yongjia; Wang, Yuhang; Lin, Kui; Xu, Zhencheng; Shao, Min

2017-10-01

Atmospheric transport of black carbon (BC) from surrounding areas has been shown to impact the Tibetan environment, and clarifying the geographical source and receptor regions is crucial for providing guidance for mitigation actions. In this study, 10 trace volatile organic compounds (VOCs) sampled across Tibet are chosen as proxies to diagnose source regions and related transport of pollutants to Tibet. The levels of these VOCs in Tibet are higher than those in the Arctic and Antarctic regions but much lower than those observed at many remote and background sites in Asia. The highest VOC level is observed in the eastern region, followed by the southern region and the northern region. A positive matrix factorization (PMF) model found that three factors-industry, biomass burning, and traffic-present different spatial distributions, which indicates that different zones of Tibet are influenced by different VOC sources. The average age of the air masses in the northern and eastern regions is estimated to be 3.5 and 2.8 days using the ratio of toluene to benzene, respectively, which indicates the foreign transport of VOC species to those regions. Back-trajectory analyses show that the Afghanistan-Pakistan-Tajikistan region, Indo-Gangetic Plain (IGP), and Meghalaya-Myanmar region could transport industrial VOCs to different zones of Tibet from west to east. The agricultural bases in northern India could transport biomass burning-related VOCs to the middle-northern and eastern zones of Tibet. High traffic along the unique national roads in Tibet is associated with emissions from local sources and neighboring areas. Our study proposes international joint-control efforts and targeted actions to mitigate the climatic changes and effects associated with VOCs in Tibet, which is a climate sensitive region and an important source of global water.

Determination of burn patient outcome by large-scale quantitative discovery proteomics

PubMed Central

Finnerty, Celeste C.; Jeschke, Marc G.; Qian, Wei-Jun; Kaushal, Amit; Xiao, Wenzhong; Liu, Tao; Gritsenko, Marina A.; Moore, Ronald J.; Camp, David G.; Moldawer, Lyle L.; Elson, Constance; Schoenfeld, David; Gamelli, Richard; Gibran, Nicole; Klein, Matthew; Arnoldo, Brett; Remick, Daniel; Smith, Richard D.; Davis, Ronald; Tompkins, Ronald G.; Herndon, David N.

2013-01-01

Objective Emerging proteomics techniques can be used to establish proteomic outcome signatures and to identify candidate biomarkers for survival following traumatic injury. We applied high-resolution liquid chromatography-mass spectrometry (LC-MS) and multiplex cytokine analysis to profile the plasma proteome of survivors and non-survivors of massive burn injury to determine the proteomic survival signature following a major burn injury. Design Proteomic discovery study. Setting Five burn hospitals across the U.S. Patients Thirty-two burn patients (16 non-survivors and 16 survivors), 19–89 years of age, were admitted within 96 h of injury to the participating hospitals with burns covering >20% of the total body surface area and required at least one surgical intervention. Interventions None. Measurements and Main Results We found differences in circulating levels of 43 proteins involved in the acute phase response, hepatic signaling, the complement cascade, inflammation, and insulin resistance. Thirty-two of the proteins identified were not previously known to play a role in the response to burn. IL-4, IL-8, GM-CSF, MCP-1, and β2-microglobulin correlated well with survival and may serve as clinical biomarkers. Conclusions These results demonstrate the utility of these techniques for establishing proteomic survival signatures and for use as a discovery tool to identify candidate biomarkers for survival. This is the first clinical application of a high-throughput, large-scale LC-MS-based quantitative plasma proteomic approach for biomarker discovery for the prediction of patient outcome following burn, trauma or critical illness. PMID:23507713

50 CFR 648.76 - Maine mahogany quahog zone.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Atlantic Surf Clam and Ocean Quahog Fisheries § 648.76 Maine mahogany quahog zone. (a) Landing requirements... Advisory Panel shall make recommendations, through the Surf Clam and Ocean Quahog Committee of the Council...

Detection of sedimentary structural elements using formation micro imager technique, a case study from South Mansoura-1 well, Nile Delta, Egypt

NASA Astrophysics Data System (ADS)

Abd El-Wahed, Ahmed G.; Anan, Tarek I.

2016-12-01

A detailed structure and sedimentology interpretation was performed for the South Mansoura-1 well. The Formation Micro Imager (FMI) is recorded and interpreted over the interval 9100-8009 ft. This interval belongs to Sidi Salem and Qawasim Formations. Based on azimuth trend of manually picked dips (bed boundaries), the interval can be divided into 4 structural dip zones (Zone 1 (9100-8800 ft), variable azimuth direction with the major trends mainly to SW&NE; Zone 2 (8800-8570 ft), bedding dip azimuth is mainly to the NW; Zone 3 (8570-8250 ft), bedding dip azimuth is mainly to the NE; and Zone 4 (8250-8009 ft), bedding dip azimuth is mainly to the NW). Lamination identified over the interval shows a dominant dip azimuth trend toward North North-West direction. The interbedded shale units are highly laminated and show little evidence of bioturbation. Sand exhibits abundant cross bedding showing a dominant dip azimuth trends toward NNE and NE and more locally to the E. Sixteen truncations identified over the interval show variable azimuth trend with the major trend mainly to the North North-West.

Nonlinear Burn Control in Tokamaks using Heating, Non-axisymmetric Magnetic Fields, Isotopic fueling and Impurity injection

NASA Astrophysics Data System (ADS)

Pajares, Andres; Schuster, Eugenio

2016-10-01

Plasma density and temperature regulation in future tokamaks such as ITER is arising as one of the main problems in nuclear-fusion control research. The problem, known as burn control, is to regulate the amount of fusion power produced by the burning plasma while avoiding thermal instabilities. Prior work in the area of burn control considered different actuators, such as modulation of the auxiliary power, modulation of the fueling rate, and controlled impurity injection. More recently, the in-vessel coil system was suggested as a feasible actuator since it has the capability of modifying the plasma confinement by generating non-axisymmetric magnetic fields. In this work, a comprehensive, model-based, nonlinear burn control strategy is proposed to integrate all the previously mentioned actuators. A model to take into account the influence of the in-vessel coils on the plasma confinement is proposed based on the plasma collisionality and the density. A simulation study is carried out to show the capability of the controller to drive the system between different operating points while rejecting perturbations. Supported by the US DOE under DE-SC0010661.

Burning mouth syndrome: a review and update.

PubMed

Silvestre, Francisco J; Silvestre-Rangil, Javier; López-Jornet, Pía

2015-05-16

Burning mouth syndrome (BMS) is mainly found in middle aged or elderly women and is characterized by intense burning or itching sensation of the tongue or other regions of the oral mucosa. It can be accompanied by xerostomia and dysgeusia. The syndrome generally manifests spontaneously, and the discomfort is typically of a continuous nature but increases in intensity during the evening and at night. Although BMS classically has been attributed to a range of factors, in recent years evidence has been obtained relating it peripheral (sensory C and/or trigeminal nerve fibers) or central neuropathic disturbances (involving the nigrostriatal dopaminergic system). The differential diagnosis requires the exclusion of oral mucosal lesions or blood test alterations that can produce burning mouth sensation. Patient management is based on the avoidance of causes of oral irritation and the provision of psychological support. Drug treatment for burning sensation in primary BMS of peripheral origin can consist of topical clonazepam, while central type BMS appears to improve with the use of antidepressants such as duloxetine, antiseizure drugs such as gabapentin, or amisulpride.

LED phototherapy in full-thickness burns induced by CO2 laser in rats skin.

PubMed

da Silva Melo, Milene; Alves, Leandro Procópio; Fernandes, Adriana Barrinha; Carvalho, Henrique Cunha; de Lima, Carlos José; Munin, Egberto; Gomes, Mônica Fernandes; Salgado, Miguel Angel Castillo; Zângaro, Renato Amaro

2018-04-27

Many studies have been conducted on the treatment of burns because they are important in morbidity and mortality. These studies are mainly focused on improving care and quality of life of patients. The aim of this study was evaluate the LED phototherapy effects in rats skin full-thickness burns induced by CO 2 laser. The animals were divided in NT group that did not received any treatment and LED group that received LED irradiation at 685 nm, 220 mW, and 4.5 J/cm 2 during 40 s by burned area. Biopsies were obtained after 7, 14, and 21 days of treatment and submitted to histological and immunohistochemical analysis. The LED phototherapy shows anti-inflammatory effects, improves angiogenesis, and stimulates the migration and proliferation of fibroblasts. The T CD8+ lymphocytes were more common in burned areas compared to T CD4+ lymphocytes since statistically significant differences were observed in the LED group compared to the NT group after 7 days of treatment. These results showed that LED phototherapy performs positive influence in full-thickness burns repair from the healing process modulated by cellular immune response. The obtained results allowed inferring that burns exhibit a characteristic cell immune response and this cannot be extrapolated to other wounds such as incision and wounds induced by punch, among others.

Seasonal and interannual variability of carbon monoxide based on MOZAIC observations, MACC reanalysis, and model simulations over an urban site in India

NASA Astrophysics Data System (ADS)

Sheel, Varun; Sahu, L. K.; Kajino, M.; Deushi, M.; Stein, O.; Nedelec, P.

2014-07-01

The spatial and temporal variations of carbon monoxide (CO) are analyzed over a tropical urban site, Hyderabad (17°27'N, 78°28'E) in central India. We have used vertical profiles from the Measurement of ozone and water vapor by Airbus in-service aircraft (MOZAIC) aircraft observations, Monitoring Atmospheric Composition and Climate (MACC) reanalysis, and two chemical transport model simulations (Model for Ozone And Related Tracers (MOZART) and MRI global Chemistry Climate Model (MRI-CCM2)) for the years 2006-2008. In the lower troposphere, the CO mixing ratio showed strong seasonality, with higher levels (>300 ppbv) during the winter and premonsoon seasons associated with a stable anticyclonic circulation, while lower CO values (up to 100 ppbv) were observed in the monsoon season. In the planetary boundary layer (PBL), the seasonal distribution of CO shows the impact of both local meteorology and emissions. While the PBL CO is predominantly influenced by strong winds, bringing regional background air from marine and biomass burning regions, under calm conditions CO levels are elevated by local emissions. On the other hand, in the free troposphere, seasonal variation reflects the impact of long-range transport associated with the Intertropical Convergence Zone and biomass burning. The interannual variations were mainly due to transition from El Niño to La Niña conditions. The overall modified normalized mean biases (normalization based on the observed and model mean values) with respect to the observed CO profiles were lower for the MACC reanalysis than the MOZART and MRI-CCM2 models. The CO in the PBL region was consistently underestimated by MACC reanalysis during all the seasons, while MOZART and MRI-CCM2 show both positive and negative biases depending on the season.

Determination of trace metals in TSP and PM2.5 materials collected in the Metropolitan Area of Monterrey, Mexico: A characterization study by XPS, ICP-AES and SEM-EDS

NASA Astrophysics Data System (ADS)

González, Lucy T.; Longoria Rodríguez, F. E.; Sánchez-Domínguez, M.; Cavazos, Aleyda; Leyva-Porras, C.; Silva-Vidaurri, L. G.; Askar, Karim Acuña; Kharissov, B. I.; Villarreal Chiu, J. F.; Alfaro Barbosa, J. M.

2017-11-01

The concentration levels of trace metals of toxicological importance were evaluated in the total suspended particles (TSP) and particulate matter smaller than 2.5 μm (PM2.5) collected in the Metropolitan Area of Monterrey (MAM) in Mexico. Samples were characterized by inductively coupled plasma atomic emission spectroscopy (ICP-AES), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy with an energy-dispersive spectroscopy system (SEM-EDS). In addition, the data were statistically treated by the methodology of Pearson Correlation (PC) and Principal Components Analysis (PCA) to identify the possible emitting sources. Surface analysis of the particulate matter (PM) by XPS revealed that the most abundant elements were Ca, Al, Na, Zn, Cu and Mg. The deconvolution of the Ca2p, Zn2p and Cu2p signals showed that the main contributors were CaCO3, ZnO and Cu/Cu2O, respectively. The bulk analysis of the PM by ICP-AES showed Fe, Cu and Zn as the most abundant elements. Fe-rich particles presented two different morphologies: the prismatic particles were associated with a natural origin, while the spherical particles with anthropogenic sources. The Zn and Cu were predominantly observed in the sampling stations with high vehicular traffic, and the emitting sources were associated with the burning of fuels from automobiles and the wear of the tires and brakes. The highest concentration of Pb was detected in the sampling station located near the industrial zones, and its cause was associated with the ceramic and glass industries, the burning of fuel oil in power plants and the production of lead-based batteries for automobiles.

Application of high-performance anion-exchange chromatography-pulsed amperometric detection for measuring carbohydrates in routine daily filter samples collected by a national network: 2. Examination of sugar alcohols/polyols, sugars, and anhydrosugars in the upper Midwest

NASA Astrophysics Data System (ADS)

Sullivan, A. P.; Frank, N.; Kenski, D. M.; Collett, J. L., Jr.

2011-04-01

Carbohydrate measurements of ambient samples can provide insights into the biogenic fraction of the organic carbon (OC) aerosol. However, lack of measurement on a routine basis limits data analysis. In a companion paper, 1 year of archived 1-in-6 day FRM (Federal Reference Monitor) filter samples from the PM2.5 NAAQS compliance monitoring network collected at 10 sites in the upper Midwest were analyzed using high-performance anion-exchange chromatography with pulsed amperometric detection to determine the regional impact of biomass burning. Along with levoglucosan, 13 other carbohydrates were simultaneously measured, including two more anhydrosugars (mannosan and galactosan), five sugars (arabinose, galactose, glucose, mannose, xylose), and six sugar alcohols/polyols (glycerol, methyltetrols, threitol/erythritol, xylitol, sorbitol, mannitol). This paper focuses on the results from these carbohydrates in order to investigate their sources and trends both spatially and temporally. Mannosan, galactosan, arabinose, xylose, and threitol/erythritol all correlated with levoglucosan (R2 from 0.43 to 0.97), suggesting biomass burning as their main source. Glucose and mannitol exhibited higher concentrations in summer and at more southern sites, likely due to vegetation differences at the sites. Using mannitol, the contribution of spores to OC was found to be <1%. Methyltetrols were highly correlated with water-soluble OC (R2 from 0.63 to 0.95) and in higher concentrations at more eastern sites. This spatial pattern is possibly due to these sites being downwind of the high isoprene emission zones that occur in the western part of the Midwest from oak forests in the Ozarks and spruce forests in the northern lake states.

Engineered Sulfur‐Resistant Catalyst System with an Assisted Regeneration Strategy for Lean‐Burn Methane Combustion

PubMed Central

Kallinen, Kauko; Maunula, Teuvo; Suvanto, Mika

2018-01-01

Abstract Catalytic combustion of methane, the main component of natural gas, is a challenge under lean‐burn conditions and at low temperatures owing to sulfur poisoning of the Pd‐rich catalyst. This paper introduces a more sulfur‐resistant catalyst system that can be regenerated during operation. The developed catalyst system lowers the barrier that has restrained the use of liquefied natural gas as a fuel in energy production. PMID:29780434

Restocking conditions on the burned-over forest lands of southwestern Maine, June 1949

Treesearch

Wayne G. Banks; James C. Rettie

1949-01-01

Disastrous fires swept over some 130,000 acres of forest land in southwestern Maine during the autumn of 1947. Practically all of the timber stand (211 million board feet of saw timber and 400,000 cords of pole timber) was killed or injured by this fire.

Ten-year epidemiology of chemical burns in western Zhejiang Province, China.

PubMed

Ye, Chunjiang; Wang, Xingang; Zhang, Yuanhai; Ni, Liangfang; Jiang, Ruiming; Liu, Liping; Han, Chunmao

2016-05-01

Chemical burns occur frequently in western Zhejiang Province. This study documents the epidemiology of chemical burns in the region using burn data from a local specialized hospital. Results from this analysis will assist in the planning of prevention strategies for high-risk occupations and groups. A 10-year retrospective analysis was conducted for all patients with chemical burns admitted to the Department of Burn and Plastic Surgery from January 2004 to December 2013. Information obtained for each patient included demographics (gender, age, occupation and education), location of the burn, cause of the burn, and categories of chemicals. Data regarding the season of admittance, prehospital treatment, wound site/size (area, region, and depth), accompanying injuries, operations, length of hospital stay and mortality were also assessed. A total of 690 patients (619 males, 71 females; average age: 30.6±12.4 years) were admitted to the department for chemical burns. Over the 10-year period, the incidence of chemical burns showed an increasing tendency. Chemical burns occurred most frequently in patients aged 20-59 years (94.79%). Most of the chemical burns were work-related, primarily in private enterprises (47.97%) and state-owned enterprises (24.93%). Operations (68.99%) and machine problems (17.26%) were the main causes of chemical burns in the workplace. With regard to burns caused by chemicals, most were caused by acids (72.01%), with hydrofluoric acid and sulphuric acid causing 51.45%. Most chemical burns occurred in the summer and autumn seasons (61.02%). The burn size was <10% of the total body surface area (TBSA) for 445 patients (64.49%), while only 26 patients (3.76%) had burns covering >40% TBSA. The most common burn sites were the upper extremities (31.57%), lower extremities (19.86%), and head and neck (28.83%). Most patients (581 (84.20%)) received water washing treatment on site immediately after exposure. The most common accompanying injuries included inhalation injury, ocular burns and digestive tract injury. The average hospital stay was 17.0±23.1 days (range 1-333 days). Surgery was performed in 146 patients (21.16%), and the overall mortality rate was 0.58%. Chemical burns are preventable. The high morbidity of chemical burns in western Zhejiang Province is related to the industrial structure of the area. Governmental management in the fields of production, transportation, and utilization of chemicals could be improved. Workplaces have the responsibility to provide safe work environments and equipment, as well as occupational education and safety training for high-risk work groups. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

78 FR 53668 - Regulated Navigation Area; Maine Kennebec Bridge Construction Zone, Kennebec River, Richmond, ME

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-30

...-AA11 Regulated Navigation Area; Maine Kennebec Bridge Construction Zone, Kennebec River, Richmond, ME... surrounding the Maine Kennebec Bridge between Richmond, ME, and Dresden, ME. This RNA allows the Coast Guard to enforce speed and wake restrictions and prohibit all vessel traffic through the RNA during bridge...

Spectral Mixture Analysis to map burned areas in Brazil's deforestation arc from 1992 to 2011

NASA Astrophysics Data System (ADS)

Antunes Daldegan, G.; Ribeiro, F.; Roberts, D. A.

2017-12-01

The two most extensive biomes in South America, the Amazon and the Cerrado, are subject to several fire events every dry season. Both are known for their ecological and environmental importance. However, due to the intensive human occupation over the last four decades, they have been facing high deforestation rates. The Cerrado biome is adapted to fire and is considered a fire-dependent landscape. In contrast, the Amazon as a tropical moist broadleaf forest does not display similar characteristics and is classified as a fire-sensitive landscape. Nonetheless, studies have shown that forest areas that have already been burned become more prone to experience recurrent burns. Remote sensing has been extensively used by a large number of researchers studying fire occurrence at a global scale, as well as in both landscapes aforementioned. Digital image processing aiming to map fire activity has been applied to a number of imagery from sensors of various spatial, temporal, and spectral resolutions. More specifically, several studies have used Landsat data to map fire scars in the Amazon forest and in the Cerrado. An advantage of using Landsat data is the potential to map fire scars at a finer spatial resolution, when compared to products derived from imagery of sensors featuring better temporal resolution but coarser spatial resolution, such as MODIS (Moderate Resolution Imaging Spectrometer) and GOES (Geostationary Operational Environmental Satellite). This study aimed to map burned areas present in the Amazon-Cerrado transition zone by applying Spectral Mixture Analysis on Landsat imagery for a period of 20 years (1992-2011). The study area is a subset of this ecotone, centered at the State of Mato Grosso. By taking advantage of the Landsat 5TM and Landsat 7ETM+ imagery collections available in Google Earth Engine platform and applying Spectral Mixture Analysis (SMA) techniques over them permitted to model fire scar fractions and delimitate burned areas. Overlaying yearly burned areas allowed to identify areas with high fire recurrence.

Stratified turbulent Bunsen flames: flame surface analysis and flame surface density modelling

NASA Astrophysics Data System (ADS)

Ramaekers, W. J. S.; van Oijen, J. A.; de Goey, L. P. H.

2012-12-01

In this paper it is investigated whether the Flame Surface Density (FSD) model, developed for turbulent premixed combustion, is also applicable to stratified flames. Direct Numerical Simulations (DNS) of turbulent stratified Bunsen flames have been carried out, using the Flamelet Generated Manifold (FGM) reduction method for reaction kinetics. Before examining the suitability of the FSD model, flame surfaces are characterized in terms of thickness, curvature and stratification. All flames are in the Thin Reaction Zones regime, and the maximum equivalence ratio range covers 0.1⩽φ⩽1.3. For all flames, local flame thicknesses correspond very well to those observed in stretchless, steady premixed flamelets. Extracted curvature radii and mixing length scales are significantly larger than the flame thickness, implying that the stratified flames all burn in a premixed mode. The remaining challenge is accounting for the large variation in (subfilter) mass burning rate. In this contribution, the FSD model is proven to be applicable for Large Eddy Simulations (LES) of stratified flames for the equivalence ratio range 0.1⩽φ⩽1.3. Subfilter mass burning rate variations are taken into account by a subfilter Probability Density Function (PDF) for the mixture fraction, on which the mass burning rate directly depends. A priori analysis point out that for small stratifications (0.4⩽φ⩽1.0), the replacement of the subfilter PDF (obtained from DNS data) by the corresponding Dirac function is appropriate. Integration of the Dirac function with the mass burning rate m=m(φ), can then adequately model the filtered mass burning rate obtained from filtered DNS data. For a larger stratification (0.1⩽φ⩽1.3), and filter widths up to ten flame thicknesses, a β-function for the subfilter PDF yields substantially better predictions than a Dirac function. Finally, inclusion of a simple algebraic model for the FSD resulted only in small additional deviations from DNS data, thereby rendering this approach promising for application in LES.

Importance of transboundary transport of biomass burning emissions to regional air quality in Southeast Asia during a high fire event

NASA Astrophysics Data System (ADS)

Aouizerats, B.; van der Werf, G. R.; Balasubramanian, R.; Betha, R.

2015-01-01

Smoke from biomass and peat burning has a notable impact on ambient air quality and climate in the Southeast Asia (SEA) region. We modeled a large fire-induced haze episode in 2006 stemming mostly from Indonesia using the Weather Research and Forecasting model coupled with chemistry (WRF-Chem). We focused on the evolution of the fire plume composition and its interaction with the urbanized area of the city state of Singapore, and on comparisons of modeled and measured aerosol and carbon monoxide (CO) concentrations. Two simulations were run with WRF-Chem using the complex volatility basis set (VBS) scheme to reproduce primary and secondary aerosol evolution and concentration. The first simulation referred to as WRF-FIRE included anthropogenic, biogenic and biomass burning emissions from the Global Fire Emissions Database (GFED3) while the second simulation referred to as WRF-NOFIRE was run without emissions from biomass burning. To test model performance, we used three independent data sets for comparison including airborne measurements of particulate matter (PM) with a diameter of 10 μm or less (PM10) in Singapore, CO measurements in Sumatra, and aerosol optical depth (AOD) column observations from four satellite-based sensors. We found reasonable agreement between the model runs and both ground-based measurements of CO and PM10. The comparison with AOD was less favorable and indicated the model underestimated AOD, although the degree of mismatch varied between different satellite data sets. During our study period, forest and peat fires in Sumatra were the main cause of enhanced aerosol concentrations from regional transport over Singapore. Analysis of the biomass burning plume showed high concentrations of primary organic aerosols (POA) with values up to 600 μg m-3 over the fire locations. The concentration of POA remained quite stable within the plume between the main burning region and Singapore while the secondary organic aerosol (SOA) concentration slightly increased. However, the absolute concentrations of SOA (up to 20 μg m-3) were much lower than those from POA, indicating a minor role of SOA in these biomass burning plumes. Our results show that about 21% of the total mass loading of ambient PM10 during the July-October study period in Singapore was due to biomass and peat burning in Sumatra, but this contribution increased during high burning periods. In total, our model results indicated that during 35 days aerosol concentrations in Singapore were above the threshold of 50 μg m-3 day-1 indicating poor air quality. During 17 days this was due to fires, based on the difference between the simulations with and without fires. Local pollution in combination with recirculation of air masses was probably the main cause of poor air quality during the other 18 days, although fires from Sumatra and probably also from Kalimantan (Indonesian part of the island of Borneo) added to the enhanced PM10 concentrations. The model versus measurement comparisons highlighted that for our study period and region the GFED3 biomass burning aerosol emissions were more in line with observations than found in other studies. This indicates that care should be taken when using AOD to constrain emissions or estimate ground-level air quality. This study also shows the need for relatively high resolution modeling to accurately reproduce the advection of air masses necessary to quantify the impacts and feedbacks on regional air quality.

Width of the Surface Rupture Zone for Thrust Earthquakes and Implications for Earthquake Fault Zoning: Chi-Chi 1999 and Wenchuan 2008 Earthquakes

NASA Astrophysics Data System (ADS)

Boncio, P.; Caldarella, M.

2016-12-01

We analyze the zones of coseismic surface faulting along thrust faults, whit the aim of defining the most appropriate criteria for zoning the Surface Fault Rupture Hazard (SFRH) along thrust faults. Normal and strike-slip faults were deeply studied in the past, while thrust faults were not studied with comparable attention. We analyze the 1999 Chi-Chi, Taiwan (Mw 7.6) and 2008 Wenchuan, China (Mw 7.9) earthquakes. Several different types of coseismic fault scarps characterize the two earthquakes, depending on the topography, fault geometry and near-surface materials. For both the earthquakes, we collected from the literature, or measured in GIS-georeferenced published maps, data about the Width of the coseismic Rupture Zone (WRZ). The frequency distribution of WRZ compared to the trace of the main fault shows that the surface ruptures occur mainly on and near the main fault. Ruptures located away from the main fault occur mainly in the hanging wall. Where structural complexities are present (e.g., sharp bends, step-overs), WRZ is wider then for simple fault traces. We also fitted the distribution of the WRZ dataset with probability density functions, in order to define a criterion to remove outliers (e.g., by selecting 90% or 95% probability) and define the zone where the probability of SFRH is the highest. This might help in sizing the zones of SFRH during seismic microzonation (SM) mapping. In order to shape zones of SFRH, a very detailed earthquake geologic study of the fault is necessary. In the absence of such a very detailed study, during basic (First level) SM mapping, a width of 350-400 m seems to be recommended (95% of probability). If the fault is carefully mapped (higher level SM), one must consider that the highest SFRH is concentrated in a narrow zone, 50 m-wide, that should be considered as a "fault-avoidance (or setback) zone". These fault zones should be asymmetric. The ratio of footwall to hanging wall (FW:HW) calculated here ranges from 1:5 to 1:3.

Atmospheric Effects of Biomass Burning

NASA Technical Reports Server (NTRS)

Thompson, Anne M.

2000-01-01

Biomass fires are both natural and anthropogenic in origin. The natural trigger is lightning, which leads to mid- and high-latitude fires and episodes of smoke and pollution associated with them. Lightning is also prominent in tropical regions when the dry season gives way to the wet season and lightning in convective systems ignites dry vegetation. Atmospheric consequences of biomass fires are complex. When considering the impacts of fires for a given ecosystem, inputs of fires must be compared to other process that emit trace gases and particles into the atmosphere. Other processes include industrial activity, fires for household purposes and biogenic sources which may themselves interact with fires. That is, fires may promote or restrict biogenic processes. Several books have presented various aspects of fire interactions with atmospheric chemistry and a cross-disciplinary review of a 1992 fire-oriented experiment appears in SAFARI: The Role of southern African Fires in Atmospheric and Ecological Environments. The IGAC/BIBEX core activity (see acronyms at end of Chapter) has sponsored field campaigns that integrate multiple aspects of fires ground-based measurements with an ecological perspective, atmospheric measurements with chemical and meteorological components, and remote sensing. This Chapter presents two aspects of biomass fires and the environment. Namely, the relationship between biomass burning and ozone is described, starting with a brief description of the chemical reactions involved and illustrative measurements and interpretation. Second, because of the need to observe biomass burning and its consequences globally, a summary of remote sensing approaches to the study of fires and trace gases is given. Examples in this Chapter are restricted to tropical burning for matters of brevity and because most burning activity globally is within this zone.

A lateral tarsorrhaphy with forehead hitch to pre-empt and treat burns ectropion with a contextual review of burns ectropion management.

PubMed

Lymperopoulos, Nikolaos S; Jordan, Daniel J; Jeevan, Ranjeet; Shokrollahi, Kayvan

2016-01-01

Facial burns around the eyes and eyelid ectropion can lead to corneal exposure, irritation, dryness, epiphora, infection or visual loss. We undertook a review of the published articles describing management of eyelid burns as well as methods to treat or prevent ectropion. We describe early experience of a surgical technique that we have found to mitigate ectropion in facial burns with peri-ocular involvement. Two illustrative cases with our surgical technique is described from our experience of three cases. We reviewed the literature using the PubMed and EMBASE databases using the search terms 'burn' and 'ectropion'. The literature review produced a total of 17 relevant papers. Treatment options for eyelid burns were varied and were invariably level 4 or 5 evidence. Various techniques were used to treat eyelid burns including the use of a full thickness skin graft with or without concurrent scar contracture release but also use of a local flap reconstruction with or without a tissue expander or release of the underlying muscle. Other techniques included canthoplasty, Z-plasty, forehead flaps, fat transfer, and tarsorrhaphy with full thickness skin grafting. In general, the focus of articles was therapeutic and reconstructive rather than pre-emptive/preventative management. We describe our early experience of a novel technique for temporary lateral tarsorrhaphy with forehead hitch which protexts the globe and counters the scar- and gravity-related ectropic effects on the lower eyelids. Facial burns pose a difficult problem to the burn surgeon, especially when the eyelids are affected, both directly or indirectly. The optimal surgical management of eyelid burns remains unclear and the literature base lies mainly in the domain of case series. We review the literature on this subject and tabulate our findings and also describe our contribution to this area with a method of lateral and lower lid elevator that we have found valuable.

Inability to determine tissue health is main indication of allograft use in intermediate extent burns.

PubMed

Fletcher, John L; Cancio, Leopoldo C; Sinha, Indranil; Leung, Kai P; Renz, Evan M; Chan, Rodney K

2015-12-01

Cutaneous allograft is commonly used in the early coverage of excised burns when autograft is unavailable. However, allograft is also applied in intermediate-extent burns (25-50%), during cases in which it is possible to autograft. In this population, there is a paucity of data on the indications for allograft use. This study explores the indications for allograft usage in moderate size burns. Under an IRB-approved protocol, patients admitted to our burn unit between March 2003 and December 2010 were identified through a review of the burn registry. Data on allograft use, total burn surface area, operation performed, operative intent, number of operations, intensive care unit length of stay, and overall length of stay were collected and analyzed. Data are presented as means±standard deviations, except where noted. In the study period, 146 patients received allograft during their acute hospitalization. Twenty-five percent of allograft recipients sustained intermediate-extent burns. Patients with intermediate-extent burns received allograft later in their hospitalization than those with large-extent (50-75% TBSA) burns (6.8 days vs. 3.4 days, p=0.01). Allografted patients with intermediate-extent burns underwent more operations (10.8 vs. 6.1, p=0.002) and had longer hospitalizations (78.3 days vs. 40.9 days, p<0.001) than non-allografted patients, when controlled for TBSA. Clinical rationale for placement of allograft in this population included autograft failure, uncertain depth of excision, lack of autograft donor site, and wound complexity. When uncertain depth of excision was the indication, allograft was universally applied onto the face. In half of allografted intermediate-extent burn patients the inability to identify a viable recipient bed was the ultimate reason for allograft use. Unlike large body surface area burns, allograft skin use in intermediate-extent injury occurs later in the hospitalization and is driven by the inability to determine wound bed suitability for autograft application. Allograft application can be utilized to test recipient site viability in cases of autograft failure or uncertain depth of excision. Published by Elsevier Ltd.

Burns inflicted by self or by others--an 11 year snapshot.

PubMed

Malic, C C; Karoo, R O S; Austin, O; Phipps, A

2007-02-01

In the United Kingdom, the incidence of assault by burning and of self inflicted burns increased significantly over the last decade. This has major implications both for service providers and society as a whole. Our aim was to investigate the differences in patients' characteristics, management and outcome following a burn sustained by either an assault or self immolation. Acute admissions to a tertiary Burn Centre were retrospectively reviewed over an 11 year period (1994-2005). Demographic data and information regarding the circumstances surrounding the incident, burn severity, treatment and outcomes of the patients were collected. Over an 11 year period, 1745 patients were admitted to the tertiary Burn Centre. Of this total, 41 patients (mean age 29 years+/-16) sustained burns following an assault, a further 86 patients (mean age of 37 years+/-12) had self inflicted burn injuries; males were preponderant in both groups. In this series, a history of alcohol or substance abuse was present in 25% of both cohorts, 63% of the patients with self inflicted injuries having a previously diagnosed psychiatric disorder. Petrol, accelerants and other flammable liquids were the main agents chosen to inflict injury in both the assault and self inflicted groups. The burn depth and surface area distribution was greater in the self inflicted group compared to those assaulted (29% versus 21%). A difference was also noted in the pattern of distribution of burns between the two groups, as well as between genders although this difference was not significant. Two-thirds (67.4%) of the self immolated patients and 56% of the assaulted group required surgery. The length of hospital stay was similar for both groups, averaging 20 days. The crude mortality for the self inflicted group was 29%, whereas in the assaulted patients, the overall mortality was 4.9%. Although the incidence of burns caused either by assault or attempted suicide is low, the affected patients require a multidisciplinary approach. Their management requires significant medical, psychological occupational and social support. Increased awareness and education of those vulnerable individuals maybe of benefit to help prevent self inflicted injuries by burning.

On the possible leakage of ET-RR1 liquid waste tank: hydrological and migration modes studies.

PubMed

Mahmoud, N S; El-Hemamy, S T

2005-03-20

The first Egyptian (ET-RR1) research reactor has been in operation since 1961 at the Egyptian Atomic Energy Authority (EAEA) Inshas site. Therefore, at present, it faces a serious problem due to aging equipment, especially those directly in contact with the environment such as the underground settling tanks of nuclear and radioactive waste. The possible leakage of radionuclides from these aging tanks and their migration to the aquifer was studied using instantaneous release. This study was done based on the geological and hydrological characteristics of the site, which were obtained from the hydrogeological data of 25 wells previously drilled at the site of the reactor[1]. These data were used to calculate the trend of water levels, hydraulic gradient, and formulation of water table maps from 1993-2002. This information was utilized to determine water velocity in the unsaturated zone. Radionuclides released from the settling tank to the aquifer were screened according to the radionuclides that have high migration ability and high activity. The amount of fission and activation products of the burned fuels that contaminated the water content of the reactor pool were considered as 10% of the original spent fuel. The radionuclides considered in this case were H-3, Sr-90, Zr-93, Tc-99, Cd-113, Cs-135, Cs-137, Sm-151, Pu-238, Pu-240, Pu-241, and Am-241. The instantaneous release was analyzed by theoretical calculations, taking into consideration the migration mechanism of the various radionuclides through the soil space between the tank bottom and the aquifer. The migration mechanism through the unsaturated zone was considered depending on soil type, thickness of the unsaturated zone, water velocity, and other factors that are specific for each radionuclide, namely retardation factor, which is the function of the specific distribution coefficient of each radionuclide. This was considered collectively as delay time. Meanwhile, the mechanism of radionuclide migration during their passage in the water body of the aquifer was the main focus of this study. The degree of water pollution in the aquifer at a point of contact with the main water body of Ismailia Canal 1000 m from the reactor site was assessed for the instantaneous release by comparing the results obtained with the regulations of the standard limit of radionuclides in drinking water.

On The Possible Leakage of ET-RR1 Liquid Waste Tank: Hydrological and Migration Modes Studies

PubMed Central

Mahmoud, N. S.; EL-Hemamy, S. T.

2005-01-01

The first Egyptian (ET-RR1) research reactor has been in operation since 1961 at the Egyptian Atomic Energy Authority (EAEA) Inshas site. Therefore, at present, it faces a serious problem due to aging equipment, especially those directly in contact with the environment such as the underground settling tanks of nuclear and radioactive waste. The possible leakage of radionuclides from these aging tanks and their migration to the aquifer was studied using instantaneous release.This study was done based on the geological and hydrological characteristics of the site, which were obtained from the hydrogeological data of 25 wells previously drilled at the site of the reactor[1]. These data were used to calculate the trend of water levels, hydraulic gradient, and formulation of water table maps from 1993–2002. This information was utilized to determine water velocity in the unsaturated zone.Radionuclides released from the settling tank to the aquifer were screened according to the radionuclides that have high migration ability and high activity. The amount of fission and activation products of the burned fuels that contaminated the water content of the reactor pool were considered as 10% of the original spent fuel. The radionuclides considered in this case were H-3, Sr-90, Zr-93, Tc-99, Cd-113, Cs-135, Cs-137, Sm-151, Pu-238, Pu-240, Pu-241, and Am-241.The instantaneous release was analyzed by theoretical calculations, taking into consideration the migration mechanism of the various radionuclides through the soil space between the tank bottom and the aquifer. The migration mechanism through the unsaturated zone was considered depending on soil type, thickness of the unsaturated zone, water velocity, and other factors that are specific for each radionuclide, namely retardation factor, which is the function of the specific distribution coefficient of each radionuclide. This was considered collectively as delay time. Meanwhile, the mechanism of radionuclide migration during their passage in the water body of the aquifer was the main focus of this study.The degree of water pollution in the aquifer at a point of contact with the main water body of Ismailia Canal 1000 m from the reactor site was assessed for the instantaneous release by comparing the results obtained with the regulations of the standard limit of radionuclides in drinking water[2,3]. PMID:15798884

Carbon and nitrogen in Type 2 supernova diamonds

NASA Astrophysics Data System (ADS)

Clayton, Donald D.; Eleid, Mounib; Brown, Lawrence E.

1993-03-01

Abundant diamonds found in meteorites seem either to have condensed within supernova interiors during their expansions and coolings or to have been present around those explosions. Either alternative allows implantation of Xe-HL prior to interstellar mixing. A puzzling feature is the near normalcy of the carbon isotopes, considering that the only C-rich matter, the He-burning shell, is pure C-12 in that region. That last fact has caused many to associate supernova carbon with C-12 carbon, so that its SUNOCONS have been anticipated as very C-12-rich. We show that this expectation is misleading because the C-13-rich regions of Type 2's have been largely overlooked in this thinking. We here follow the idea that the diamonds nucleated in the C-12-rich He shell, the only C-rich site for nucleation, but then attached C-13-rich carbon during turbulent encounters with overlying C-13-rich matter. That is, the initial diamonds continued to grow during the same collisional encounters that cause the Xe-HL implantation. Instead of interacting with the small carbon mass having 13/12 = 0.2 in the upper He zone, however, we have calculated the remnants of the initial H-burning core, which left behind C-13-rich matter as it receded during core hydrogen burning. Howard et al. described why the velocity mixing would be essential to understanding the implantation of both the Xe-H and Xe-L components. Velocity mixing is now known to occur from the X-ray and gamma-ray light curves of supernova 1987A. Using the stellar evolution code developed at Goettingen, we calculated at Clemson the evolution of a grid of massive stars up to the beginning of core He burning. We paid attention to all H-burning reactions throughout the star, to the treatment of both convection and semiconvection, and to the recession of the outer boundary of the convective H-burning core as the star expands toward a larger redder state. This program was to generate a careful map of the CNO isotope distribution as He burning begins. Our result for the 30 solar mass star is shown.

Combustion of Metals in Carbon Dioxide and Reduced-Gravity Environments

NASA Technical Reports Server (NTRS)

Branch, M. C.; Abbud-Madrid, A.; Modak, A.; Dreyer, C. B.; Daily, J. W.

2001-01-01

Ongoing exploration and future mission2001110444 s to Mars have given impetus to research on the use of natural resources of the planet. Since carbon dioxide (CO2) constitutes approximately 95% of the Mars atmosphere and since it reacts directly and vigorously with several metals, this investigation focuses on metal-CO2 reactions as a possible combination for rocket-propellant production and energy generation. Magnesium (Mg) has been initially selected as the metal fuel owing to its low ignition temperature and high specific impulse and burning rate in CO2. Our studies in this field started with low gravity (g) combustion tests of Mg in O2, CO2, and CO. Reduced gravity provided a clear picture of the burning phenomena by eliminating the intrusive buoyant flows in high-temperature metal reactions and by removing the destructive effect of gravity on the shape of molten metal samples. Suspended cylindrical metal samples of 2, 3, and 4-mm in diameter and length were radiatively ignited in low-g to generate free-floating samples exhibiting a spherically symmetric flame with increasing metal-oxide accumulation in an outer shell. For the Mg-CO2 combination, burning times twice as long as in normal-g and five times longer than in Mg-O2 flames were observed, revealing a diffusion-controlled reaction. The burning time is proportional to the square of the sample diameter. In tests conducted with pure CO, combustion was not possible without constant heating of the sample due to the formation of a thick carbon-containing coating around the Mg sample generated by surface reactions. The following work presents two new studies that attempt to explain some of the low-g experimental observations. First, a simplified one-dimensional, quasi-steady numerical model is developed to obtain temperature, species concentrations, and burning rates of the spherically symmetric diffusion flame around the Mg sample burning in O2 and CO2. Second, a Planar Laser Induced Fluorescence (PLIF) technique is implemented to provide spatially resolved measurements of magnesium oxide (MgO) in the reaction zone of Mg samples burning in O2 and CO2. These experiments reveal fundamental differences between the two combustion systems.

The Geoland2 BioPar burned area product

NASA Astrophysics Data System (ADS)

Tansey, K.; Bradley, A.; Smets, B.; van Best, C.; Lacaze, R.

2012-04-01

The European Commission Geoland2 project intends to constitute a major step forward to the implementation of the GMES Land Monitoring Core Service (LMCS). The Bio-geophysical Parameters (BioPar) Core Monitoring Service aims at setting-up pre-operational infrastructures for providing regional, European, and global bio-geophysical variables, both in near real time and off-line mode, for describing the vegetation state, the radiation budget at the surface, and the water cycle. The burned area product is part of the BioPar portfolio. The burned area product further builds on the experience of the Global Burned Area (GBA2000) and L3JRC projects. In the GBA2000 project, several algorithms were developed for different geographical regions of the world, and applied to a 1-year time series (the year 2000) of SPOT-VEGETATION data. In the L3JRC project, a single algorithm was improved and applied to a 7-year global dataset of SPOT-VEGETATION data. Since the conception of the Geoland2 project, work has been undertaken to improve the L3JRC algorithm, mainly based on user comments and feedback. Furthermore, the Geoland2 burned area product specification has been developed to meet the requirements of the Core Information Service, specifically LandCarbon and Natural Resource Monitoring in Africa (Narma). The Geoland2 burned area product has the following improvements over the L3JRC product: • It resolves issues with users extracting statistics and burned area estimates for time periods considered to be outside the main seasons for burning. Specifically, this deals with issues in northern latitude winters. • The number of pre-processing steps has been shortened, reducing processing time. • An improved land-water mask has been used. This resolves a problem around the coastlines of land masses which were frequently being detected as being burned. • A season metric calculation is performed over a 1x1 degree grid. For each grid cell, a date is logged against the start of the fire season, peak of the fire season and then the end of the fire season. Once a fire season has been confirmed as being finished, the region effectively resets itself, which means that the land surface can burn again when the next fire season starts. This automated season reset feature enables multiple fire seasons to be analysed. • Provides easy to interpret seasonality tables every 10 days (the reporting period for the product). It is intended that the product will be validated using CEOS-approved protocols and data sets currently being developed through the European Space Agency Fire-CCI project. In this paper, initial results being produced operationally and will be presented along with examples highlighting the performance of the seasonality metric.

Three-dimensional direct numerical simulation of turbulent lean premixed methane combustion with detailed kinetics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aspden, A. J.; Day, M. S.; Bell, J. B.

The interaction of maintained homogeneous isotropic turbulence with lean premixed methane flames is investigated using direct numerical simulation with detailed chemistry. The conditions are chosen to be close to those found in atmospheric laboratory experiments. As the Karlovitz number is increased from 1 to 36, the preheat zone becomes thickened, while the reaction zone remains largely unaffected. A negative correlation of fuel consumption with mean flame surface curvature is observed. With increasing turbulence intensity, the chemical composition in the preheat zone tends towards that of an idealised unity Lewis number flame, which we argue is the onset of the transitionmore » to distributed burning, and the response of the various chemical species is shown to fall into broad classes. Smaller-scale simulations are used to isolate the specific role of species diffusion at high turbulent intensities. Diffusion of atomic hydrogen is shown to be related to the observed curvature correlations, but does not have significant consequential impact on the thickening of the preheat zone. It is also shown that susceptibility of the preheat zone to thickening by turbulence is related to the 'global' Lewis number (the Lewis number of the deficient reactant); higher global Lewis number flames tend to be more prone to thickening.« less

Three-dimensional direct numerical simulation of turbulent lean premixed methane combustion with detailed kinetics

DOE PAGES

Aspden, A. J.; Day, M. S.; Bell, J. B.

2016-02-18

The interaction of maintained homogeneous isotropic turbulence with lean premixed methane flames is investigated using direct numerical simulation with detailed chemistry. The conditions are chosen to be close to those found in atmospheric laboratory experiments. As the Karlovitz number is increased from 1 to 36, the preheat zone becomes thickened, while the reaction zone remains largely unaffected. A negative correlation of fuel consumption with mean flame surface curvature is observed. With increasing turbulence intensity, the chemical composition in the preheat zone tends towards that of an idealised unity Lewis number flame, which we argue is the onset of the transitionmore » to distributed burning, and the response of the various chemical species is shown to fall into broad classes. Smaller-scale simulations are used to isolate the specific role of species diffusion at high turbulent intensities. Diffusion of atomic hydrogen is shown to be related to the observed curvature correlations, but does not have significant consequential impact on the thickening of the preheat zone. It is also shown that susceptibility of the preheat zone to thickening by turbulence is related to the 'global' Lewis number (the Lewis number of the deficient reactant); higher global Lewis number flames tend to be more prone to thickening.« less

Puerarin attenuates severe burn-induced acute myocardial injury in rats.

PubMed

Liu, Sheng; Ren, Hong-Bo; Chen, Xu-Lin; Wang, Fei; Wang, Ren-Su; Zhou, Bo; Wang, Chao; Sun, Ye-Xiang; Wang, Yong-Jie

2015-12-01

Puerarin, the main isoflavone glycoside extracted from the root of Pueraria lobata, is widely prescribed for patients with cardiovascular disorders in China. This study investigates the effect of puerarin on severe burn-induced acute myocardial injury in rats and its underlying mechanisms. Healthy adult Wistar rats were divided into three groups: (1) sham group, sham burn treatment; (2) burn group, third-degree burns over 30% of the total body surface area (TBSA) with lactated Ringer's solution for resuscitation; and (3) burn plus puerarin group, third-degree burns over 30% of TBSA with lactated Ringer's solution containing puerarin for resuscitation. The burned animals were sacrificed at 1, 3, 6, 12, and 24 h after burn injury. Myocardial injury was evaluated by analyzing serum creatine kinase MB fraction (CK-MB) activity and cardiac troponin T (cTNT) level. Changes in cardiomyocyte ultrastructure were also determined using a transmission electron microscope. Tumor necrosis factor (TNF)-α concentration in serum was measured by radioimmunoassay. Cardiac myeloperoxidase (MPO) activity and malondialdehyde (MDA) concentration were measured to determine neutrophil infiltration and oxidative stress in the heart, respectively. The expression of p38 mitogen-activated protein (MAP) kinase in the heart was determined by Western blot analysis. After the 30% TBSA full-thickness burn injury, serum CK-MB activities and cTnT levels increased markedly, both of which were significantly decreased by the puerarin treatment. The level of serum TNF-α concentration in burn group at each time-point was obviously higher than those in sham group (1.09±0.09 ng/ml), and it reached the peak value at 12 h post burn. Burn trauma also resulted in worsen ultrastructural condition, elevated MPO activity and MDA content in heart tissue, and a significant activation of cardiac p38 MAP kinase. Administration of puerarin improved the ultrastructural changes in cardiomyocytes, decreased TNF-α concentration in serum as well as suppressed cardiac MPO activity and reduced MDA content, and abolished the activation of p38 MAP kinase in heart tissue after severe burn. These results suggest that puerarin attenuates inflammatory responses, reduces neutrophil infiltration and oxidative stress in the heart, and protects against acute myocardial injury induced by severe burn. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

Developing and implementing a plan for large-scale burn disaster response in New Jersey.

PubMed

Conlon, Kathe M; Ruhren, Chris; Johansen, Sandra; Dimler, Margaret; Frischman, Barbara; Gehringer, Eileen; Houng, Abraham; Marano, Michael; Petrone, Sylvia J; Mansour, E Hani

2014-01-01

For the first time in modern history burn centers must face the reality of having to potentially care for a staggering number of injured patients. Factors such as staffing, patient acuity and bed availability compel medical professionals to regularly examine various aspects of their respective healthcare delivery systems, especially with regards to how these systems should function for mass casualty response. The majority of burn care in New Jersey is provided by one designated burn treatment facility. A planning group was formed to identify additional hospital support systems capable of providing short-term patient care during a disaster. Focus was on three key areas: identifying actual versus potential nonburn center resources, ascertaining the number and level of burn expertise at these facilities, and assessing the capacities of any available resources and personnel. Retrospective review of discharge data highlighted which of the more than seventy New Jersey hospitals besides The Burn Center were treating and releasing burn injures. In a disaster The Burn Center designates these hospitals as Tier Facilities to serve as additional resources until patients may be transferred to other recognized regional and national burn centers. Triage is conducted in accordance with the American Burn Association Benefit-to-Ratio Triage grid, matching patient acuity with each hospital's tier designation. A secondary triage, conducted 24 hours after the initial incident, identifies which patients require transport for more specialized burn care. Twenty-seven burn centers from Maine through Maryland and the District of Columbia, who have joined together as a Consortium, agree to support one another for optimal patient distribution and management in accordance with accepted national standards of care. State Medical Coordination Centers equipped to coordinate and track transport of large numbers of injured personnel are able to facilitate this collaborative, multiagency response throughout the northeast region. Burn centers share many issues common to emergency preparedness. Paramount among them is an ability to provide quality burn care for the greatest number of patients at a time when staff and resources will be severely limited. It is incumbent upon burn centers to explore opportunities extending beyond individual state and regional resources in order for centers to continually maintain this standard of care, particularly in a disaster.

CHARACTERIZATION OF PARTICULATE MATTER EMISSION FROM OPEN BURNING OF RICE STRAW

PubMed Central

Oanh, Nguyen Thi Kim; Bich, Thuy Ly; Tipayarom, Danutawat; Manadhar, Bhai R.; Prapat, Pongkiatkul; Simpson, Christopher D.; Liu, L-J Sally

2010-01-01

Emission from field burning of crop residue, a common practice in many parts of the world today, has potential effects on air quality, atmosphere and climate. This study provides a comprehensive size and compositional characterization of particulate matter (PM) emission from rice straw (RS) burning using both in situ experiments (11 spread field burning) and laboratory hood experiments (3 pile and 6 spread burning) that were conducted during 2003–2006 in Thailand. The carbon balance and emission ratio method was used to determine PM emission factors (EF) in the field experiments. The obtained EFs varied from field to hood experiments reflecting multiple factors affecting combustion and emission. In the hood experiments, EFs were found to be depending on the burning types (spread or pile), moisture content and the combustion efficiency. In addition, in the field experiments, burning rate and EF were also influenced by weather conditions, i.e. wind. Hood pile burning produced significantly higher EF (20±8 g kg−1 RS) than hood spread burning (4.7±2.2 g kg−1 RS). The majority of PM emitted from the field burning was PM2.5 with EF of 5.1±0.7 g m−2 or 8.3±2.7 g kg−1 RS burned. The coarse PM fraction (PM10-2.5) was mainly generated by fire attention activities and was relatively small, hence the resulting EF of PM10 (9.4±3.5 g kg−1 RS) was not significantly higher than PM2.5. PM size distribution was measured across 8 size ranges (from <0.4 μm to >9.0 μm). The largest fractions of PM, EC and OC were associated with PM1.1. The most significant components in PM2.5 and PM10 include OC, water soluble ions and levoglucosan. Relative abundance of some methoxyphenols (e.g., acetylsyringone), PAHs (e.g., fluoranthene and pyrene), organochlorine pesticides and PCBs may also serve as additional signatures for the PM emission. Presence of these toxic compounds in PM of burning smoke increases the potential toxic effects of the emission. For illustration, an estimation of the annual RS field burning in Thailand was made using the obtained in situ field burning EFs and preliminary burning activity data. PMID:21243095

Determination of Pass/Fail Criteria for Promoted Combustion Testing

NASA Technical Reports Server (NTRS)

Sparks, Kyle M.; Stoltzfus, Joel M.; Steinberg, Theodore A.; Lynn, David

2009-01-01

Promoted ignition testing is used to determine the relative flammability of metal rods in oxygen-enriched atmospheres. In these tests, a promoter is used to ignite each metal rod to start the sample burning. Experiments were performed to better understand the promoted ignition test by obtaining insight into the effect a burning promoter has on the preheating of a test sample. Test samples of several metallic materials were prepared and coupled to fast-responding thermocouples along their length. Various ignition promoters were used to ignite the test samples. The thermocouple measurements and test video was synchronized to determine temperature increase with respect to time and length along each test sample. A recommended length of test sample that must be consumed to be considered a flammable material was determined based on the preheated zone measured from these tests. This length was determined to be 30 mm (1.18 in.). Validation of this length and its rationale are presented.

The effect of solid phase reactions on the ballistic properties of propellants

NASA Technical Reports Server (NTRS)

Schmidt, W. G.

1970-01-01

The combustion of NH4ClO4 composite propellants has been studied between 15 and 3000 psi. The emphasis in the program has been on determining the mechanisms by which the fuel components influence the burning rate of the composites. In order to have flexibility in the choice and concentration of the fuel component all combustion experiments were performed with pressed power strands. The fuels studied included those which affected the combustion mechanism of the composite primarily through their effect on: (1) the oxidizer decomposition mechanism and (2) the composite surface temperature. The combustion of pure and doped NH4ClO4 was studied using both pressed powder strands and pressed end burning motor grains. The experimental approach has been essentially a chemical one with emphasis on perturbing those reactions which occur on or immediately adjacent to the surface (zone of influence) of the composite.

Nucleosynthesis in the first massive stars

NASA Astrophysics Data System (ADS)

Choplin, Arthur; Meynet, Georges; Maeder, André; Hirschi, Raphael; Chiappini, Cristina

2018-01-01

The nucleosynthesis in the first massive stars may be constrained by observing the surface composition of long-lived very iron-poor stars born around 10 billion years ago from material enriched by their ejecta. Many interesting clues on physical processes having occurred in the first stars can be obtained based on nuclear aspects. First, in these first massive stars, mixing must have occurred between the H-burning and the He-burning zone during their nuclear lifetimes; Second, only the outer layers of these massive stars have enriched the material from which the very iron-poor stars, observed today in the halo of the MilkyWay, have formed. These two basic requirements can be obtained by rotating stellar models at very low metallicity. In the present paper, we discuss the arguments supporting this view and illustrate the sensitivity of the results concerning the [Mg/Al] ratio on the rate of the reaction 23Na(p,γ)24Mg.

Validation of the German version of the Burn Specific Health Scale-Brief (BSHS-B).

PubMed

Müller, Astrid; Smits, Dirk; Jasper, Stefanie; Berg, Lea; Claes, Laurence; Ipaktchi, Ramin; Vogt, Peter M; de Zwaan, Martina

2015-09-01

The Burn Specific Health Scale-Brief (BSHS-B) is recognized as a valid self-rating scale to evaluate quality of life after burn. To validate the translated German version of the BSHS-B. One hundred and forty one burn survivors (65.2% men) with a mean age of 49.62 years (SD=15.16) and a mean duration after burn of 45.01 months (SD=26.18) answered the BSHS-B. Factor structure was tested by using confirmatory factor analysis, reliability (internal consistency) of the scales was determined by means of Cronbach's α. Construct validity was explored through correlations between the BSHS-B and the Short-Form 8 Health Survey (SF-8). In addition, the know-groups technique was used to determine to which degree the BSHS-B discriminates between patients with low and high burn severity based on the abbreviated burn severity index (ABSI). The Hospital Anxiety and Depression Scale (HADS) was used to examine criterion validity. The nine BSHS-B subscales showed good internal consistency. A second-order confirmatory factor analysis revealed the following main components: (1) Affect and Relationship, (2) Function and (3) Skin Involvement. The second-order factors were positively correlated with the SF-8 and negatively correlated with symptoms of anxiety and depression. Patients with low ABSI scored higher on all three BSHS-B domains than those with high ABSI. The results indicate good psychometric properties of the German BSHS-B. Further studies are needed to investigate the utility of the questionnaire in clinical routine practice, evaluation of burn management programs, and burn-specific research. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

The last 10 years in a burn centre in Ankara, Turkey: an analysis of 5264 cases.

PubMed

Türegün, M; Sengezer, M; Selmanpakoglu, N; Celiköz, B; Nişanci, M

1997-01-01

This is a retrospective study analysing 5264 patients treated in the burn centre at Gülhane Military Medical Academy from 1 January 1986 to 31 December 1995. Our burn centre is not only the first, but one of the best established and supported in Turkey. Our present study has the largest patient group of other previously published studies from Turkey. Of the total patients studied, 4464 patients had minor burns and were treated on an outpatient basis and 800 patients had moderate to major burns. Although our centre is in a military area in Ankara, only 1047 (20 per cent) patients were military personnel and the military-related burn causes comprised only 6 per cent of the total. The remaining 4217 (80 per cent of the total patients) were civilians. Flame injuries were also more frequent in military patients than civilians. Minor burns were most common in the age group 0-10 years old (40 per cent) and moderate to major burns in the age group 21-30 years (54 per cent). Scalds were the main cause of paediatric burns. Male patients were dominant. The overall mortality among inpatients was 18.2 per cent and mean total body surface area (TBSA) was 57.6 per cent in patients who died. 134 patients demonstrated inhalation injury and 82 per cent of these patients died. The epidemiological pattern of our patients is similar to that in other studies from developed countries, although some ethnic causative factors could be found. Our study indicates that emergency measures should be taken to prevent flame injuries at military barracks and industrial workplaces and scalding accidents to children at home and throughout the country.

Single particle size and fluorescence spectra from emissions of burning materials in a tube furnace to simulate burn pits

NASA Astrophysics Data System (ADS)

Pan, Yong-Le; Houck, Joshua D. T.; Clark, Pamela A.; Pinnick, Ronald G.

2013-08-01

A single-particle fluorescence spectrometer (SPFS) and an aerodynamic particle sizer were used to measure the fluorescence spectra and particle size distribution from the particulate emissions of 12 different burning materials in a tube furnace to simulate open-air burning of garbage. Although the particulate emissions are likely dominated by particles <1 μm diameter, only the spectra of supermicron particles were measured here. The overall fluorescence spectral profiles exhibit either one or two broad bands peaked around 300-450 nm within the 280-650 nm spectral range, when the particles are illuminated with a 263-nm laser. Different burning materials have different profiles, some of them (cigarette, hair, uniform, paper, and plastics) show small changes during the burning process, and while others (beef, bread, carrot, Styrofoam, and wood) show big variations, which initially exhibit a single UV peak (around 310-340 nm) and a long shoulder in visible, and then gradually evolve into a bimodal spectrum with another visible peak (around 430-450 nm) having increasing intensity during the burning process. These spectral profiles could mainly derive from polycyclic aromatic hydrocarbons with the combinations of tyrosine-like, tryptophan-like, and other humic-like substances. About 68 % of these single-particle fluorescence spectra can be grouped into 10 clustered spectral templates that are derived from the spectra of millions of atmospheric aerosol particles observed in three locations; while the others, particularly these bimodal spectra, do not fall into any of the 10 templates. Therefore, the spectra from particulate emissions of burning materials can be easily discriminated from that of common atmospheric aerosol particles. The SFFS technology could be a good tool for monitoring burning pit emissions and possibly for distinguishing them from atmospheric aerosol particles.

Changes after partial cutting of a spruce-fir stand in Maine

Treesearch

Arthur C. Hart

1956-01-01

In 1945 a partial-cutting experiment in spruce-fir silviculture was begun by the Penobscot Research Center of the Northeastern Forest Experiment Station. The Eastern Pulp Wood Company of Calais, Maine, made available for the study a tract of forest land, in Dyer Township, Washington County, Maine. This 20.6-acre tract is part of a large area that had been burned over...

Saturday night burns: an increasing problem?

PubMed Central

Bollero, D.; Malvasio, V.; Gangemi, E.N.; Giunta, G.; Collard, B.; Stella, M.

2015-01-01

Summary In Italy the economic crisis has caused changes in behavior in daily as well as leisure activities. For instance, night clubs have changed both their scenography and what they can offer. From simply providing a place to dance, they can now offer more complex scenography with spectacular fireworks and lit cocktails. While this can be amazing for all of us it can also be another cause of burn injuries. We conducted a retrospective study of all burns patients admitted to the Accident and Emergency Department at CTO Hospital in Turin from 2009 to 2013, after a night clubbing. A total of five patients were identified with an average age of 20 years old: four were burned by flaming cocktails and one was burned by a firework. Two received outpatient treatment, while orotracheal intubation and admission were needed for three, and two required surgical debridement and resurfacing with split skin graft. All patients had permanent sequelae caused by pathologic scarring and/or dyschromia. Our findings show that the risk of burn injuries is higher at weekends, mainly in summer, if all correct safety procedures are not followed. Meanwhile it is important to highlight that the promotion of inappropriate behavior at night clubs during firework displays and the passing of flaming cocktails should be avoided. PMID:26668565

Effects of Minoxidil Gel on Burn Wound Healing in Rats

PubMed Central

Khazaeli, Payam; Karamouzian, Mohammad; Rohani, Shohreh; Sadeghirad, Behnam; Ghalekhani, Nima

2014-01-01

Minoxidil has been reported to inhibit in-vitro fibroblast proliferation and lysyl hydroxylase activity, a key enzyme in collagen biosynthesis. These in-vitro effects proposed minoxidil to be a potential antifibrotic agent. The present study aimed to investigate the effects of minoxidil gel on wound healing procedure in a second-degree burn model in rats. Wistar rats were anesthetized and a second-degree burn was induced on the back of Wistar rats using a heated 2 cm diameter metal plate. Experimental groups received 2% or 5% topical minoxidil gel, dexpanthenol or sliver sulfadiazine. Histological parameters including collagen content, angiogenesis, number of preserved follicles and necrosis along with tensile strength of burn wound area were assessed on days 3, 7, 14 and 21 post-injury.Microscopic evaluation of specimens collected from sample animals were consistent and showed a second-degree burn. Main histological findings regarding minoxidil topical usage showed that collagen content and tensile strength of burned area did not differ between groups. However, minoxidil increased the number and diameter of blood vessels significantly compared with other groups.Although minoxidil improved the process of wound-healing, our results did not support the proposed idea of its usage as an antifibrotic agent. However, to reject its possible effects as an antifibrotic agent, more objective animal models should be developed and studied. PMID:24734077

Saturday night burns: an increasing problem?

PubMed

Bollero, D; Malvasio, V; Gangemi, E N; Giunta, G; Collard, B; Stella, M

2015-03-31

In Italy the economic crisis has caused changes in behavior in daily as well as leisure activities. For instance, night clubs have changed both their scenography and what they can offer. From simply providing a place to dance, they can now offer more complex scenography with spectacular fireworks and lit cocktails. While this can be amazing for all of us it can also be another cause of burn injuries. We conducted a retrospective study of all burns patients admitted to the Accident and Emergency Department at CTO Hospital in Turin from 2009 to 2013, after a night clubbing. A total of five patients were identified with an average age of 20 years old: four were burned by flaming cocktails and one was burned by a firework. Two received outpatient treatment, while orotracheal intubation and admission were needed for three, and two required surgical debridement and resurfacing with split skin graft. All patients had permanent sequelae caused by pathologic scarring and/or dyschromia. Our findings show that the risk of burn injuries is higher at weekends, mainly in summer, if all correct safety procedures are not followed. Meanwhile it is important to highlight that the promotion of inappropriate behavior at night clubs during firework displays and the passing of flaming cocktails should be avoided.

Prescribed Burning and Clear-Cutting Effects on Understory Vegetation in a Pinus canariensis Stand (Gran Canaria)

PubMed Central

Arévalo, José Ramón; García-Domínguez, Celia; Naranjo-Cigala, Agustín; Grillo, Federico

2014-01-01

Prescribed fires are a powerful tool for reducing fire hazards by decreasing amounts of fuel. The main objective is to analyze the effects of prescribed burning on the understory vegetation composition as well as on the soil characteristics of a reforested stand of Pinus canariensis. The study attempts to identify the effects of the preburning treatment of cutting understory vegetation on the floristic parameters of the vegetation community. This study was carried out for two years following a prescribed fire in a Canarian pine stand. Cutting and burning treatment affected species composition and increased diversity. Burnt and cut plots were characterized by a diverse array of herbaceous species and by a lower abundance of Teline microphylla (endemic legume), although burning apparently induced its germination. Cut treatment was more consistently differentiated from the control plots than burnt treatment. Soil K decreased after both treatments, pH slightly decreased after cutting, while P and Ca increased after fire. From an ecological point of view, prescribed burning is a better management practice than cutting the woody species of the understory. However, long-term studies would be necessary to evaluate the effects of fire intensity, season and frequency in which the prescribed burning is applied. PMID:25147839

Prescribed burning and clear-cutting effects on understory vegetation in a Pinus canariensis stand (Gran Canaria).

PubMed

Arévalo, José Ramón; Fernández-Lugo, Silvia; García-Domínguez, Celia; Naranjo-Cigala, Agustín; Grillo, Federico; Calvo, Leonor

2014-01-01

Prescribed fires are a powerful tool for reducing fire hazards by decreasing amounts of fuel. The main objective is to analyze the effects of prescribed burning on the understory vegetation composition as well as on the soil characteristics of a reforested stand of Pinus canariensis. The study attempts to identify the effects of the preburning treatment of cutting understory vegetation on the floristic parameters of the vegetation community. This study was carried out for two years following a prescribed fire in a Canarian pine stand. Cutting and burning treatment affected species composition and increased diversity. Burnt and cut plots were characterized by a diverse array of herbaceous species and by a lower abundance of Teline microphylla (endemic legume), although burning apparently induced its germination. Cut treatment was more consistently differentiated from the control plots than burnt treatment. Soil K decreased after both treatments, pH slightly decreased after cutting, while P and Ca increased after fire. From an ecological point of view, prescribed burning is a better management practice than cutting the woody species of the understory. However, long-term studies would be necessary to evaluate the effects of fire intensity, season and frequency in which the prescribed burning is applied.

Evaluation of ground-water flow and solute transport in the Lompoc area, Santa Barbara County, California

USGS Publications Warehouse

Bright, Daniel J.; Nash, David B.; Martin, Peter

1997-01-01

Ground-water quality in the Lompoc area, especially in the Lompoc plain, is only marginally acceptable for most uses. Demand for ground water has increased for municipal use since the late 1950's and has continued to be high for irrigation on the Lompoc plain, the principal agricultural area in the Santa Ynez River basin. As use has increased, the quality of ground water has deteriorated in some areas of the Lompoc plain. The dissolved-solids concentration in the main zone of the upper aquifer beneath most of the central and western plains has increased from less than 1,000 milligrams per liter in the 1940's to greater than 2,000 milligrams per liter in the 1960's. Dissolved- solids concentration have remained relatively constant since the 1960's. A three-dimensional finite-difference model was used to simulate ground-water flow in the Lompoc area and a two-dimensional finite-element model was used to simulate solute transport to gain a better understanding of the ground-water system and to evaluate the effects of proposed management plans for the ground-water basin. The aquifer system was simulated in the flow model as four horizontal layers. In the area of the Lompoc plain, the layers represent the shallow, middle, and main zones of the upper aquifer, and the lower aquifer. For the Lompoc upland and Lompoc terrace, the four layers represent the lower aquifer. The solute transport model was used to simulate dissolved-solids transport in the main zone of the upper aquifer beneath the Lompoc plain. The flow and solute-transport models were calibrated to transient conditions for 1941-88. A steady-state simulation was made to provide initial conditions for the transient-state simulation by using long-term average (1941-88) recharge rates. Model- simulated hydraulic heads generally were within 5 feet of measured heads in the main zone for transient conditions. Model-simulated dissolved- solids concentrations for the main zone generally differed less than 200milligrams per liter from concentrations in 1988. During 1941-88 about 1,096,000 acre-feet of water was pumped from the aquifer system. Average pumpage for this period (22,830 acre-feet per year) exceeded pumpage for the steady-state simulation by 16,590 acre-feet per year. The results of the transient simulation indicate that about 60 percent of this increase in pumpage was contributed by increased recharge, 28 percent by decreased natural discharge from the system (primarily discharge to the Santa Ynez River and transpiration), and 13 percent was withdrawn from storage. Total simulated downward leakage from the middle zone to the main zone in the central plain and upward leakage from the consolidated rocks to the main zone significantly increased in response to increased pumpage, which increased from about 6,240 to 30,870 acre-feet per year from 1941 to 1988. Average dissolved-solid concentration in the middle zone in 1987-88 ranged from 2,000 to 3,000 milligrams per liter beneath the northeastern plain and the dissolved-solids concentration of two samples from the consolidated rocks beneath the western plain averaged 4,300 milligrams per liter. Because the dissolved-solids concentration for the middle zone and the consolidated rocks is higher than the simulated steady-state dissolved-solids concentration of the main zone, the increase in the leakage from these two sources resulted in increased dissolved-solids concentration in the main zone during the transient period. The model results indicate that the main source of increased dissolved- solids concentration in the northeastern and central plains was downward leakage from the middle zone; whereas, upward leakage from the consolidated rocks was the main source of the increased dissolved-solids concentrations in the northwestern and western plains. The models were used to estimate changes in hydraulic head and in dissolved-solids concentration resulting from three proposed management alternatives: (1) average recharge

Characterization of post-fire surface cover, soils, and burn severity at the Cerro Grande Fire, New Mexico, using hyperspectral and multispectral remote sensing

USGS Publications Warehouse

Kokaly, R.F.; Rockwell, B.W.; Haire, S.L.; King, T.V.V.

2007-01-01

Forest fires leave behind a changed ecosystem with a patchwork of surface cover that includes ash, charred organic matter, soils and soil minerals, and dead, damaged, and living vegetation. The distributions of these materials affect post-fire processes of erosion, nutrient cycling, and vegetation regrowth. We analyzed high spatial resolution (2.4??m pixel size) Airborne Visible and Infrared Imaging Spectrometer (AVIRIS) data collected over the Cerro Grande fire, to map post-fire surface cover into 10 classes, including ash, soil minerals, scorched conifer trees, and green vegetation. The Cerro Grande fire occurred near Los Alamos, New Mexico, in May 2000. The AVIRIS data were collected September 3, 2000. The surface cover map revealed complex patterns of ash, iron oxide minerals, and clay minerals in areas of complete combustion. Scorched conifer trees, which retained dry needles heated by the fire but not fully combusted by the flames, were found to cover much of the post-fire landscape. These scorched trees were found in narrow zones at the edges of completely burned areas. A surface cover map was also made using Landsat Enhanced Thematic Mapper plus (ETM+) data, collected September 5, 2000, and a maximum likelihood, supervised classification. When compared to AVIRIS, the Landsat classification grossly overestimated cover by dry conifer and ash classes and severely underestimated soil and green vegetation cover. In a comparison of AVIRIS surface cover to the Burned Area Emergency Rehabilitation (BAER) map of burn severity, the BAER high burn severity areas did not capture the variable patterns of post-fire surface cover by ash, soil, and scorched conifer trees seen in the AVIRIS map. The BAER map, derived from air photos, also did not capture the distribution of scorched trees that were observed in the AVIRIS map. Similarly, the moderate severity class of Landsat-derived burn severity maps generated from the differenced Normalized Burn Ratio (dNBR) calculation had low agreement with the AVIRIS classes of scorched conifer trees. Burn severity and surface cover images were found to contain complementary information, with the dNBR map presenting an image of degree of change caused by fire and the AVIRIS-derived map showing specific surface cover resulting from fire.

Impact of fire disturbance on soil thermal and carbon dynamics in Alaskan Tundra and Boreal forest ecosystems

NASA Astrophysics Data System (ADS)

Jiang, Y.; Rastetter, E.; Shaver, G. R.; Rocha, A. V.

2012-12-01

In Alaska, fire disturbance is a major component influencing the soil water and energy balance in both tundra and boreal forest ecosystems. Fire-caused changes in soil environment further affect both above- and below-ground carbon cycles depending on different fire severities. Understanding the effects of fire disturbance on soil thermal change requires implicit modeling work on the post-fire soil thawing and freezing processes. In this study, we model the soil temperature profiles in multiple burned and non-burned sites using a well-developed soil thermal model which fully couples soil water and heat transport. The subsequent change in carbon dynamics is analyzed based on site level observations and simulations from the Multiple Element Limitation (MEL) model. With comparison between burned and non-burned sites, we compare and contrast fire effects on soil thermal and carbon dynamics in continuous permafrost (Anaktuvik fire in north slope), discontinuous permafrost (Erickson Creek fire at Hess Creek) and non-permafrost zone (Delta Junction fire in interior Alaska). Then we check the post-fire recovery of soil temperature profiles at sites with different fire severities in both tundra and boreal forest fire areas. We further project the future changes in soil thermal and carbon dynamics using projected climate data from Scenarios Network for Alaska & Arctic Planning (SNAP). This study provides information to improve the understanding of fire disturbance on soil thermal and carbon dynamics and the consequent response under a warming climate.

[Burns in childhood. Social implications in the eve of the year 2000].

PubMed

Abad, P; Acosta, D; Martínez Ibáñez, V; Lloret, J; Patiño, B; Gubern, L; Carol, J; Boix Ochoa, J

2000-07-01

The thermic wounds in childhood are the third cause of morbility at hospital in our ambiance. The knowledge about incidence, the causal agents more frequent, and the detailed analysis of different variants about the subject are the unique manner to try to establish precautions against. The aim of this project is to analyse the factors and situations associated with thermic wound, through the retrospective study about the patients admitted. During three years, 362 patients were admitted at hospital, between 0 and 14 years old, following the criterion: barge burn size more than 10%, critical location (hands, face, neck), causal agent (electricity, chemical) or social situation. Different facts were analyzed about provenance, place, causal agent, burned part of the body, degree of lesion and the average stay at hospital. There were 59.6% males, and 40.3% females. Children between 1 and 5 years old, represented the largest group of patients, 205 cases. The 66% were from other hospital were they receive the first aid. The 98.7% were burned at home, and the place more frequent was kitchen, 51%. The causal agent was liquid in 65.4%, specially scald with water about 104 cases. The zones more affected were the face (39.2%), and the superior extremities, about 81% second degree superficial or deep. The size was 10 to 20% in 19% of patients, and more than 40% in 0.2% of children. The average stay was 17.47 days at hospital.

Method of producing thermally sprayed metallic coating

DOEpatents

Byrnes, Larry Edward [Rochester Hills, MI; Kramer, Martin Stephen [Clarkston, MI; Neiser, Richard A [Albuquerque, NM

2003-08-26

The cylinder walls of light metal engine blocks are thermally spray coated with a ferrous-based coating using an HVOF device. A ferrous-based wire is fed to the HVOF device to locate a tip end of the wire in a high temperature zone of the device. Jet flows of oxygen and gaseous fuel are fed to the high temperature zone and are combusted to generate heat to melt the tip end. The oxygen is oversupplied in relation to the gaseous fuel. The excess oxygen reacts with and burns a fraction of the ferrous-based feed wire in an exothermic reaction to generate substantial supplemental heat to the HVOF device. The molten/combusted metal is sprayed by the device onto the walls of the cylinder by the jet flow of gases.

Pathways of nitrogen loss following land clearing in a humid tropical forest

NASA Technical Reports Server (NTRS)

Matson, Pamela; Vitousek, Peter

1985-01-01

Tropical deforestation generally leads to large losses of carbon and nitrogen. The Premontane Wet Forest Life Zone is subject to the highest rate of deforestation in Central America, and carbon and nutrient losses in from these fertile soils is very rapid and extreme. Losses of 2000 to 3000 kgN/ha have been reported. Losses of this magnitude could be extremely significant on a regional or global scale if even a small proportion of this nitrogen is lost as nitrous oxide to the atmosphere or through leaching of nitrate to rivers. This study seeks to measure the rates and regulation of nitrogen transformations, and the pathways of nitrogen losses following land clearing and burning at a site in the Premontane Wet Forest Life Zone near Turrialba, Costa Rica.

A synthesis of post-fire Burned Area Reports from 1972 to 2009 for western US Forest Service lands: Trends in wildfire characteristics and post-fire stabilisation treatments and expenditures

Treesearch

Peter R. Robichaud; Hakjun Rhee; Sarah A. Lewis

2014-01-01

Over 1200 post-fire assessment and treatment implementation reports from four decades (1970s-2000s) of western US forest fires have been examined to identify decadal patterns in fire characteristics and the justifications and expenditures for the post-fire treatments. The main trends found were: (1) the area burned by wildfire increased over time and the rate of...

Optical properties and possible sources of brown carbon in PM2.5 over Xi'an, China

NASA Astrophysics Data System (ADS)

Shen, Zhenxing; Zhang, Qian; Cao, Junji; Zhang, Leiming; Lei, Yali; Huang, Yu; Huang, R.-J.; Gao, Jinjin; Zhao, Zhuzi; Zhu, Chongshu; Yin, Xiuli; Zheng, Chunli; Xu, Hongmei; Liu, Suixin

2017-02-01

To quantify optical and chemical properties of PM2.5 brown carbon (BrC) in Xi'an, 58 high-volume ambient PM2.5 samples were collected during 2 November 2009 to 13 October 2010. Mass concentrations of chemical components were determined, including water-soluble ions, water-soluble organic carbon, levoglucosan, organic carbon (OC), and element carbon (EC). BrC, as an unidentified and wavelength-dependent organic compound, was also measured from water-soluble carbon (WSOC) at 340 nm using UV-vis spectrometer. The wavelength-dependent absorption coefficient (babs) and mass absorption coefficient (MAC) were much abundant at 340 nm, and the high Absorption Ångström coefficient (AAC) values were observed around 5.4, corresponding to the existence of BrC in ambient PM2.5, especially in winter. Good correlations (R > 0.60) between babs and biomass burning markers, such as levoglucosan and K+, in winter indicated significant amounts of primary BrC from biomass burning emissions. Secondary organic carbon BrC (SOCsbnd BrC) was more abundant in winter than in summer. SOCsbnd BrC in winter was mainly fresh SOC formed from aqueous phase reactions while in summer, aged SOC from photo-chemical formation. Source profiles of BrC optical parameters were detected, which verified sources of BrC from biomass burning and coal burning emissions in areas surrounding Xi'an. The rapidly decreasing babs-340nm values from biomass burning smoldering to straw pellet burning suggested that burning straw pellet instead of burning straw directly is an effective measure for reducing BrC emissions.

LA50 in burn injuries.

PubMed

Seyed-Forootan, K; Karimi, H; Motevalian, S A; Momeni, M; Safari, R; Ghadarjani, M

2016-03-31

Burn injuries put a huge financial burden on patients and healthcare systems. They are the 8th leading cause of mortality and the 13th most common cause of morbidity in our country. We used data from our Burn Registry Program to evaluate risk factors for mortality and lethal area fifty percent (LA50) in all burn patients admitted over two years. We used multiple logistic regressions to identify risk factors for mortality. LA50 is a reliable aggregate index for hospital care quality and a good measure for comparing results, also with those of other countries. 28,690 burn patients sought medical attention in the Emergency Department, and 1721 of them were admitted. Male to female ratio was 1,75:1. 514 patients were under 15 years old. Median age was 25 (range: 3 months - 93 years). Overall, probability of death was 8.4%. LA50 was 62.31% (CI 95%: 56.57-70.02) for patients aged 15 and over and 72.52% (CI 95%: 61.01-100) for those under 15. In the final model, we found that Adjusted OR was significant for age, female sex, TBSA and inhalation injury (P < 0.05). LA50 values showed that children tolerate more extensive burns. Female sex, burn size, age and inhalation injury were the main risk factors for death. Authorities should pay special attention to these variables, especially in prevention programs, to reduce mortality and improve patient outcome. Children have better outcome than adults given equal burn size. Suicide rates are higher for women than men in our country.

Expert assessment of vulnerability of permafrost carbon to climate change

USGS Publications Warehouse

Schuur, E.A.G.; Abbott, B.W.; Bowden, W.B.; Brovkin, V.; Camill, P.; Canadell, J.G.; Chanton, J.P.; Chapin, F. S.; Christensen, T.R.; Ciais, P.; Crosby, B.T.; Czimczik, C.I.; Grosse, G.; Harden, J.; Hayes, D.J.; Hugelius, G.; Jastrow, J.D.; Jones, J.B.; Kleinen, T.; Koven, C.D.; Krinner, G.; Kuhry, P.; Lawrence, D.M.; McGuire, A.D.; Natali, Susan M.; O'Donnell, J. A.; Ping, C.-L.; Riley, W.J.; Rinke, A.; Romanovsky, V.E.; Sannel, A.B.K.; Schädel, C.; Schaefer, K.; Sky, J.; Subin, Z.M.; Tarnocai, C.; Turetsky, M.R.; Waldrop, M.P.; Anthony, K.M. Walter; Wickland, K.P.; Wilson, C.J.; Zimov, S.A.

2013-01-01

Approximately 1700 Pg of soil carbon (C) are stored in the northern circumpolar permafrost zone, more than twice as much C than in the atmosphere. The overall amount, rate, and form of C released to the atmosphere in a warmer world will influence the strength of the permafrost C feedback to climate change. We used a survey to quantify variability in the perception of the vulnerability of permafrost C to climate change. Experts were asked to provide quantitative estimates of permafrost change in response to four scenarios of warming. For the highest warming scenario (RCP 8.5), experts hypothesized that C release from permafrost zone soils could be 19–45 Pg C by 2040, 162–288 Pg C by 2100, and 381–616 Pg C by 2300 in CO2 equivalent using 100-year CH4 global warming potential (GWP). These values become 50 % larger using 20-year CH4 GWP, with a third to a half of expected climate forcing coming from CH4 even though CH4 was only 2.3 % of the expected C release. Experts projected that two-thirds of this release could be avoided under the lowest warming scenario (RCP 2.6). These results highlight the potential risk from permafrost thaw and serve to frame a hypothesis about the magnitude of this feedback to climate change. However, the level of emissions proposed here are unlikely to overshadow the impact of fossil fuel burning, which will continue to be the main source of C emissions and climate forcing.

Expert assessment of vulnerability of permafrost carbon to climate change

DOE PAGES

Schuur, E. A. G.; Abbott, B. W.; Bowden, W. B.; ...

2013-03-26

Approximately 1700 Pg of soil carbon (C) are stored in the northern circumpolar permafrost zone, more than twice as much C than in the atmosphere. The overall amount, rate, and form of C released to the atmosphere in a warmer world will influence the strength of the permafrost C feedback to climate change. We used a survey to quantify variability in the perception of the vulnerability of permafrost C to climate change. Experts were asked to provide quantitative estimates of permafrost change in response to four scenarios of warming. For the highest warming scenario (RCP 8.5), experts hypothesized that Cmore » release from permafrost zone soils could be 19–45 Pg C by 2040, 162–288 Pg C by 2100, and 381–616 Pg C by 2300 in CO 2 equivalent using 100-year CH 4 global warming potential (GWP). These values become 50% larger using 20-year CH 4 GWP, with a third to a half of expected climate forcing coming from CH 4 even though CH 4 was only 2.3 % of the expected C release. Experts projected that two-thirds of this release could be avoided under the lowest warming scenario (RCP 2.6). These results highlight the potential risk from permafrost thaw and serve to frame a hypothesis about the magnitude of this feedback to climate change. However, the level of emissions proposed here are unlikely to overshadow the impact of fossil fuel burning, which will continue to be the main source of C emissions and climate forcing.« less

Erosion and channel changes due to extreme flooding in the Fourmile Creek catchment, Colorado

NASA Astrophysics Data System (ADS)

Wicherski, Will; Dethier, David P.; Ouimet, William B.

2017-10-01

Infrequent, large magnitude geomorphic events generate quantifiable change on geologically short timescales and are crucial to understanding landscape evolution. Airborne lidar surveys and field measurements were used to investigate floodplain erosion and deposition along a 19.5 km reach of Fourmile Creek, Colorado that was devastated by severe flooding in 2013 that followed a 2010 wildfire. > 350 mm of rain fell on the Fourmile catchment from September 9-15, 2013, generating discharge that exceeded bankfull for > 120 h at the Orodell gage, with local unit stream power > 300 W m- 2 throughout the study reach. Debris flows occurred on steep hillslopes and tributary channels in the most intensely burned areas. Lidar difference measurements and field studies highlight zones of local deposition along the study reach, but demonstrate overall net erosion of 0.25 m for the 19.5 km reach of Fourmile floodplain, mainly by channel widening. Tributary junctions where debris-flow sediment entered the floodplain and local decreases in unit stream power controlled some zones of deposition. Overall, mass balance calculations show that a total sediment loss of 91,000-161,000 m3 from the Fourmile Creek floodplain and hillslopes, which is broadly consistent with channel sediment flux estimates of 71,000-111,000 m3. Measurements from the Fourmile catchment demonstrate that floodplain erosion was a major source of sediment in the 2013 flood and demonstrate that infrequent events marked by long-duration flooding and high total energy expenditure can account for a large fraction of total sediment transport in mountain streams.

Knowledge, attitude, and belief regarding burn first aid among caregivers attending pediatric emergency medicine departments.

PubMed

Alomar, Mohammed; Rouqi, Faisal Al; Eldali, Abdelmoneim

2016-06-01

Emergency departments witness many cases of burns that can be prevented with various first-aid measures. Immediate and effective burn first aid reduces morbidity and determines the outcome. Thus, it is imperative that measures of primary burn prevention and first-aid knowledge be improved. This descriptive study determines the current level of knowledge, attitude, and belief regarding burn first aid among caregivers. Caregivers attending four pediatric emergency departments answered a structured questionnaire for demographic information, knowledge, and the burn first aid they provide including two case scenarios. Applying cold water for 15-20min, smothering burning clothes, and covering the pot of oil on fire with a wet cloth were considered appropriate responses. The main outcome measure was the proportion of caregivers who were aware of burn first aid and did not use inappropriate remedies. Additional questions regarding the best means of educating the public on burn first aid were included. Individual chi-squared tests and univariate logistic regressions were performed to correlate knowledge with demographic features, history of burns, and first-aid training. The 408 interviewed caregivers (55% women) reflected a wide range of age, occupation, and educational level. Sixty percent (60%) of respondents had a large family, with 52% reporting a history of burns. Overall, 41% treated burns with cool or cold water, although 97% had inappropriate or no knowledge of the duration. Further, 32% treated burns with nonscientific remedies alone or in combination, including honey, egg white, toothpaste, white flour, tomato paste, yogurt, tea, sliced potato, butter, or ice. Only 15% had first-aid training. While 65% of caregivers covered a pot of oil on fire with a wet cloth, only 24% reported smothering burning clothes. Participants preferred learning more of first aid for burns via social media (41%), hospital visits (30%), and television (TV) (16%). No significant correlation was found between age, family size, language, history of burns, or training and knowledge; however, female gender and higher educational level were associated with increased awareness, although this was not statistically significant (p=0.05 and p=0.17, respectively). The logistic regression accounting for all significant variables showed that the history of burns had the greatest effect on knowledge of first aid (p<0.03). Knowledge of burn first aid among caregivers is limited, with many resorting to non-scientific remedies. Use of social media, hospital visits, and TV for first-aid education might improve caregivers' awareness. A nationwide educational program emphasizing first-aid application of only cold water and reduced use of inappropriate home remedies for burns is recommended. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

Examining patterns of bat activity in Bandelier National Monument, New Mexico, using walking point transects

USGS Publications Warehouse

Ellison, L.E.; Everette, A.L.; Bogan, M.A.

2005-01-01

We conducted a preliminary study using small field crews, a single Anabat II detector coupled with a laptop computer, and point transects to examine patterns of bat activity at a scale of interest to local resource managers. The study was conducted during summers of 1996–1998 in Bandelier National Monument in the Jemez Mountains of northern New Mexico, a landscape with distinct vegetation zones and high species richness of bats. We developed simple models that described general patterns of acoustic activity within 4 vegetation zones based primarily on nightly variation and a qualitative index of habitat complexity. Bat acoustic activity (number of bat passes&sol point) did not vary dramatically among a limited sample of transects within a vegetation zone during 1996. In 1997 and 1998, single transects within each vegetation zone were established, and bat activity did not vary annually within these zones. Acoustic activity differed among the 4 vegetation zones of interest, with the greatest activity occurring in riparian canyon bottomland, intermediate activity in coniferous forest and a 1977 burned zone, and lowest activity in piñon-juniper woodlands. We identified 68.5% of 2,529 bat passes recorded during point-transect surveys to species using an echolocation call reference library we established for the area and qualitative characteristics of bat calls. Bat species richness and composition differed among vegetation zones. Results of these efforts were consistent with general knowledge of where different bat species typically forage and with the natural history of bats of New Mexico, suggesting such a method might have value for drawing inferences about bat activity in different vegetation zones.

Cumulative effects of wildfires on forest dynamics in the eastern Cascade Mountains, USA.

PubMed

Reilly, Matthew J; Elia, Mario; Spies, Thomas A; Gregory, Matthew J; Sanesi, Giovanni; Lafortezza, Raffaele

2018-03-01

Wildfires pose a unique challenge to conservation in fire-prone regions, yet few studies quantify the cumulative effects of wildfires on forest dynamics (i.e., changes in structural conditions) across landscape and regional scales. We assessed the contribution of wildfire to forest dynamics in the eastern Cascade Mountains, USA from 1985 to 2010 using imputed maps of forest structure (i.e., tree size and canopy cover) and remotely sensed burn severity maps. We addressed three questions: (1) How do dynamics differ between the region as a whole and the unburned portion of the region? (2) How do dynamics vary among vegetation zones differing in biophysical setting and historical fire frequency? (3) How have forest structural conditions changed in a network of late successional reserves (LSRs)? Wildfires affected 10% of forests in the region, but the cumulative effects at this scale were primarily slight losses of closed-canopy conditions and slight gains in open-canopy conditions. In the unburned portion of the region (the remaining 90%), closed-canopy conditions primarily increased despite other concurrent disturbances (e.g., harvest, insects). Although the effects of fire were largely dampened at the regional scale, landscape scale dynamics were far more variable. The warm ponderosa pine and cool mixed conifer zones experienced less fire than the region as a whole despite experiencing the most frequent fire historically. Open-canopy conditions increased slightly in the mixed conifer zone, but declined across the ponderosa pine zone even with wildfires. Wildfires burned 30% of the cold subalpine zone, which experienced the greatest increase in open-canopy conditions and losses of closed-canopy conditions. LSRs were more prone to wildfire than the region as a whole, and experienced slight declines in late seral conditions. Despite losses of late seral conditions, wildfires contributed to some conservation objectives by creating open habitats (e.g., sparse early seral and woodland conditions) that otherwise generally decreased in unburned landscapes despite management efforts to increase landscape diversity. This study demonstrates the potential for wildfires to contribute to regional scale conservation objectives, but implications for management and biodiversity at landscape scales vary geographically among biophysical settings, and are contingent upon historical dynamics and individual species habitat preferences. © 2017 by the Ecological Society of America.

Mapping of Student Sustainable Development Education Knowledge in Malaysia Using Geographical Information System (GIS)

ERIC Educational Resources Information Center

Mahat, Hanifah; Hashim, Mohmadisa; Nayan, Nasir; Saleh, Yazid; Norkhaidi, Saiyidatina Balkhis

2018-01-01

This article aims to examine the levels of education for sustainable development (ESD) knowledge among students in secondary schools according to zones in Malaysia by using GIS mapping. The five main zones of the study were the north zone, the south zone, the east coast zone, the central zone, and the East Malaysia zone. This quantitative form of…

The Secondary Contact Zone of Phylogenetic Lineages of the Philaenus spumarius (Hemiptera: Aphrophoridae): An Example of Incomplete Allopatric Speciation

PubMed Central

Lis, Agata; Maryańska-Nadachowska, Anna; Lachowska-Cierlik, Dorota; Kajtoch, Łukasz

2014-01-01

Abstract Previous studies on the phylogeography of the meadow spittlebug Philaenus spumarius (L.) (Hemiptera: Aphrophoridae) suggest the existence of a contact zone of its main phylogenetic lineages along mountain chains in Europe and western Asia. This study presents a detailed examination of the population genetics of P. spumarius within the Carpathian Mountains. The main objective was to determine whether the populations inhabiting that area consist of individuals belonging to different genetic units and whether the observed pattern could be an example of secondary contact zone which formed after incomplete allopatric speciation. Specimens from six transects across the Carpathian arc were examined. The mitochondrial phylogeography of the meadow spittlebug in the examined area clearly shows that individuals from both main clades meet and mix there. Representatives of all three main EF1-α clades were also found. The present distribution of the main clades with a zone of overlap along the mountain ranges may suggest that these phylogenetic lineages form a young hybrid zone. Moreover, a limited number of individuals were shown to possess heteroplasmic mitochondrial DNA, which gives additional support to intraspecific hybridization. P. spumarius could be used in future work as an excellent model species in investigating population genetics, intraspecific hybridization, and speciation in progress. PMID:25500280

[Structure of newly formed capillaries of the rabbit cornea (electron microscopic study)].

PubMed

Gurina, O Iu; Karaganov, Ia L

1984-08-01

Owing to a complex application of topical analysis and tracer technique, it is possible to carry out a light optic and electron microscopic investigation of newly formed capillaries growing in the rabbit cornea after its chemical burn. The ultrastructural analysis demonstrates certain polymorphism of morphological organization of endotheliocyte in the newly formed capillaries. There is a rather elevated amount of free ribosomes, mitochondria, microtubules and microfilaments in cytoplasm. The granular endoplasmic reticulum and Golgi complex are hypertrophied. Weibel--Palade bodies appear. Taking into account certain morpho-functional peculiarities of endothelial cells along the course of the growing capillaries, on the 8th day of growth three zone are distinguished: 1--area of nondifferentiated endothelium (apex of the capillary), 2--transitional zone, 3--zone of relatively differentiated endothelium situating in the place where the capillary gets off the parental vessel. According to the zones distinguished, the ways of trans-endothelial transport of molecules are investigated. In formation of the capillary barrier-transport function an important role belongs to polymorphism of the endothelial cells along the course of the growing capillary which is determined by differentiation degree of these cells depending on their participation in permeability.

A Two-Zone Multigrid Model for SI Engine Combustion Simulation Using Detailed Chemistry

DOE PAGES

Ge, Hai-Wen; Juneja, Harmit; Shi, Yu; ...

2010-01-01

An efficient multigrid (MG) model was implemented for spark-ignited (SI) engine combustion modeling using detailed chemistry. The model is designed to be coupled with a level-set-G-equation model for flame propagation (GAMUT combustion model) for highly efficient engine simulation. The model was explored for a gasoline direct-injection SI engine with knocking combustion. The numerical results using the MG model were compared with the results of the original GAMUT combustion model. A simpler one-zone MG model was found to be unable to reproduce the results of the original GAMUT model. However, a two-zone MG model, which treats the burned and unburned regionsmore » separately, was found to provide much better accuracy and efficiency than the one-zone MG model. Without loss in accuracy, an order of magnitude speedup was achieved in terms of CPU and wall times. To reproduce the results of the original GAMUT combustion model, either a low searching level or a procedure to exclude high-temperature computational cells from the grouping should be applied to the unburned region, which was found to be more sensitive to the combustion model details.« less

Cloudy cornea

MedlinePlus

... Injury to the eye, including chemical burns and welding injury Scarring Clouding may affect all or part ... examine your eyes and ask about your medical history. The two main questions will be if your ...

Exploration for gold mineralization in the Arabo Nubian Shield: Using remote sensing Approach

NASA Astrophysics Data System (ADS)

Ramadan, Talaat

2013-04-01

In the southern part of the Eastern Desert of Egypt, Landsat Thematic Mapper (ETM+) data and fieldwork was combined with mineralogical and geochemical investigations in order to detect and characterize alteration zones within Pan-African rocks. The processing of Landsat ETM+ data using ratioing (bands 5/7,5/1,4/3 in Red, Green, Blue) showed two different types of alteration zones (type l and 2). Type 1 is close to the ophiolitic ultramafic rocks and type 2 is located within island-arc related metavolcanic rocks at the study areas. Both of these alteration zones are concordant with the main NW-SE structural trend. Mineralogical studies indicate that the alteration zones of type 1 consist mainly of calcite, ankerite, magnesite, dolomite and quartz. Chromian spinel, pyrite, and Ni-bearing sulphides (gersdorffite, pentlandite and polydymite) are the main ore minerals within this zone. Alteration zones of type 2 are strongly potassium-enriched and pyrophyllite, kaolinite, illite, gypsum and quartz occur. The brecciated quartz-veins associated with theses alteration zones consist of quartz, Fe-hydroxides, hematite and native gold. The gold content reaches up to 5 g/t in the alteration zone, while it extends up to 50 g/t in the quartz veins. This study presents a mineralogical characterization of such zones and demonstrates the utility of orbital remote sensing for finding unknown alteration zones in the Eastern Desert and other arid areas with similar host rock lithologies.

KSC-97pc402

NASA Image and Video Library

1997-03-06

Workers take off the protective covering on the propulsion module for the Cassini spacecraft after uncrating the module at KSC's Spacecraft Assembly and Encapsulation Facility-2 (SAEF-2). The extended journey of 6.7 years to Saturn and the 4-year mission for Cassini once it gets there will require the spacecraft to carry a large amount of propellant for inflight trajectory-correction maneuvers and attitude control, particularly during the science observations. The propulsion module has redundant 445-newton main engines that burn nitrogen tetraoxide and monomethyl-hydrazine for main propulsion and 16 smaller 1-newton engines that burn hydrazine to control attitude and to correct small deviations from the spacecraft flight path. Cassini will be launched on a Titan IVB/Centaur expendable launch vehicle. Liftoff is targeted for October 6 from Launch Complex 40, Cape Canaveral Air Station

Geothermal, Geochemical and Geomagnetic Mapping Of the Burning Coal Seam in Fire- Zone 18 of the Coal Mining Area Wuda, Inner Mongolia, PR China.

NASA Astrophysics Data System (ADS)

Kessels, W.; Han, J.; Halisch, M.; Lindner, H.; Rueter, H.; Wuttke, M. W.

2008-12-01

Spontaneous combustion of coal has become a world wide problem caused by and affecting technical operations in coal mining areas. The localization of the burning centre is a prerequisite for any planning of fire fighting operations. In the German - Chinese coal fire project sponsored by the German Ministry of Science and Technologies (Grant No. 0330490K) the so called fire zone 18 of the coal mining area of Wuda (InnerMongolia, PR China) serves as a test area for geophysical measurements. For the geothermal and geochemical mapping 25 up to 1m deep boreholes with a diameter of approx. 30 mm are distributed over the particular fire-zone with an extension of 320 × 180 m2. To avoid the highly dynamic gas flow processes in fire induced fractures caused by weather conditions, all boreholes were situated in the undisturbed rock compartments. In these boreholes, plastic tubes of 12 mm diameter provide access to the borehole ground filled with highly permeable gravel. The boreholes are otherwise sealed to the atmosphere by clay. The geothermal observations consist of measurements of temperature profiles in the boreholes and thermal conductivity measurement on rock samples in the lab. For depths greater then 0.2 m diurnal variations in the temperature gradient were neglected. The derived heat flow with maximum values of 80 W/m2 is more then three orders of magnitude higher than the natural undisturbed heat flow. The high heat flow suggests that the dominant heat transport is gas convection through the system of porous rock and fractures. Any temperature anomaly caused by the burning coal in a depth of more than 18 m would need years to reach the surface by a heat transport restricted to conduction. The geochemical soil gas probing is performed by gas extraction from the boreholes. Measured are the concentrations of O2, CO, CO2, H2S and CH4. The O2 deficit in the soil air and the concentrations of the other combustion products compared to the concentrations in the free atmosphere are related to the combustion area. The magnetic mapping with point distances of 2 m and profile-distances of 3 to 4 m covered an area of 350 × 300m with 7913 points. The detected anomalies lie in a range between -130 and 176 nT. The maxima are most likely caused by heating of the top sandstones by burning coal, the origin for the high magnetization being the conversion of pyrite and markasit into maghemite, hematite and magnetite. Susceptibility measurements of clinkers in firezone 18 demonstrate this effect. Therefore the identified patches with high magnetic anomalies should have a direct connection to ranges with burning coal within firezone 18. Al the discussed geophysical measurements together allow an integrated interpretation. Each result can be related to the combustion process with a particular likelihood for the vertical projection to the combustion centre. Probability calculations with chosen weight factors for each observation method are discussed. References: Kessels, W., Wuttke, M. W., Wessling, S., and Li, X. Coalfires between self ignition and fire fighting: Numerical modeling and basic geophysical measurements. In ERSEC Ecological Book Series - 4 on Coal Fire Research (2007).

An educational board game for learning and teaching burn care: A preliminary evaluation.

PubMed

Whittam, Alexander M; Chow, Whitney

2017-01-01

Timely and effective assessment, resuscitation and transfer of patients with severe burns has been demonstrated to improve outcome. A dedicated one-day course exists to equip all frontline emergency healthcare workers with the necessary knowledge and skills to manage severe burn injuries. More recently, a board game has been developed which aims to act as a learning and practice development tool for those managing burn injuries. We present the findings of our preliminary evaluation of this game. We played this game with a multidisciplinary group of staff including doctors, nurses and therapists. A proportion of these participants had previously completed the Emergency Management of Severe Burns (EMSB) course. We obtained subjective results from a questionnaire, using both Likert-type ratings and open-ended questions. The styling of the game and ease of instructions was rated from 'average' to 'excellent'. The relevance of questions was rated from 'good' to 'excellent'. The usefulness of the game to increase knowledge and stimulate discussion was rated between 'good' and 'excellent'. All participants stated that they would recommend the game to other healthcare professionals. This is the only burns and plastic surgery-related educational game in the literature. Educational games adhere to principles of adult learning but there is insufficient evidence in the literature to either confirm or refute their utility. Our preliminary evaluation of this game has shown that it achieves its main aims, namely to increase knowledge in burn care and to stimulate discussion. Further work is required to assess the board game.

Burnt wives in Tehran: a warm tragedy of self-injury

PubMed Central

Ramim, Tayeb; Mobayen, Mohammadreza; Shoar, Nasrin; Naderan, Mohammad; Shoar, Saeed

2013-01-01

Objective: To investigate the characteristics and causes of self burning among married women in the capital of Iran. Methods: Thirty five victims of self immolation were enrolled in our study during the 4 years of study period. All patients were married attempting suicide by burning themselves. Of these, no one was diagnosed to suffer from a mental or psychological disorder. Results: A statistically significant difference was observed between age groups in terms of education, occupation, and income (p<0.05). In 42.9% of the cases, burning has occurred between 12:00 and 18:00 significantly different from other times (p<0.05). 45.7% of the incidents took place in the courtyard of the house followed by 8% in bathroom, 8% in the kitchen, 2% in dining room, and 1% at the outdoor which revealed a statistically significant difference (p< 0.05). 91.4% of the women had used petroleum as a substance for burning which was significantly different with other substances (p<0.05). 60% of the victims put their spouse in charge of the main cause for their attempts to self- burning with a statistically significant difference with other causes (p<0.05). Conclusion: Married women who attempted to burn their lives were young wives from low socioeconomic status living in a traditional environment. Time and place of the burning showed that they attempt suicide more likely while they are doing daily routines. PMID:23386987

Feather conditions and clinical scores as indicators of broilers welfare at the slaughterhouse.

PubMed

Saraiva, S; Saraiva, C; Stilwell, G

2016-08-01

The objective of this study was to evaluate the welfare of 64 different broiler farms on the basis of feather conditions and clinical scores measures collected at the slaughterhouse. A 3-point scale (0, 1 or 2) was used to classify dirty feathers, footpad dermatitis and hock burns measures, and a 2-point scale (present or absent) was used to classify breast burns, breast blisters and breast ulcer measures. Flocks were allocated into three body weight (BW) classes (A, B, C): class A (light) ≥1.43 and ≤1.68kg, class B (medium) ≥1.69 and ≤1.93kg; class C (heavy) ≥1.94 and ≤2.41kg. The absence of hock burns was more common in class A, while mild hock burns was more common in class B flocks. Breast ulcer was observed in class C flocks. The association observed for mild hock burns, breast burns and severe footpad dermatitis can indicate a simultaneous occurrence of these painful lesions. Very dirty feathers and severe footpad dermatitis relationship suggest litter humidity to be the common underlying cause. In conclusion, it was shown that clinical indicators can be used at the slaughterhouse to identify welfare problems. In the studied flocks, footpad dermatitis, feather conditions and hock burns were the main restrictions for good welfare and should be considered significant welfare indicators of the on-farm rearing conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Making meaning in a burn peer support group: qualitative analysis of attendee interviews.

PubMed

Davis, Trevor; Gorgens, Kim; Shriberg, Janet; Godleski, Matthew; Meyer, Laura

2014-01-01

There is a paucity of literature on the personal experiences of burn support group members, the members' perceived benefits of group participation, and the meaning the survivors make of the support they receive. In order to provide effective psychosocial rehabilitation services and to meet the needs of burn survivors, it is important to understand the influence a support group has on its members as well as the personal experiences of those individuals who attend these groups. The purpose of this study was to explore the experiences of burn survivors in a burn survivor support group. Six self-identified burn survivors were interviewed by using a guided in-depth interview technique to explore their experiences in the support group. Key informant interviews and group observations served to triangulate the findings from the individual interviews. The experiences of the group members coalesced around four main themes: acceptance of self, perspective change, value of community, and reciprocity. The findings demonstrated the overall perceived positive impact the support group had on psychosocial recovery. For these members, the group aided the process of adjustment through the encouragement of adaptive coping strategies and the facilitation of community and relationships. Their experiences mirrored much of the literature on psychological growth from adversity. Burn survivors reported unique opportunities that allowed them to integrate their injury into their identity within an encouraging and safe environment. Using these accounts, the authors generated clinical suggestions that may encourage similar growth in other support group settings.

Profile of children and adolescents admitted to a Burn Care Unit in the countryside of the state of São Paulo☆

PubMed Central

Biscegli, Terezinha Soares; Benati, Larissa Delázari; Faria, Rafaela Sperandio; Boeira, Taís Romano; Cid, Felipe Biscegli; Gonsaga, Ricardo Alessandro Teixeira

2014-01-01

Objective: To describe the profile of pediatric burn victims hospitalized at Hospital-Escola Padre Albino (HEPA), in Catanduva, São Paulo, Brazil. Methods: This was a cross-sectional, retrospective study analyzing 446 medical records of patient aged 0-18 years old hospitalized in the Burn Care Unit of HEPA, from 2002 to 2012. The following variables were recorded: demographic data, skin burn causes, lesions characteristics, complications, surgical procedures, length of hospital stay, and outcome. Descriptive statistics were used. Results: 382 patients with full medical records were included in the study. Burns were more frequent in males (64.4%) and in children aged less than 6 years (52.9%). Most accidents occurred at home (67.3%) and hot liquids were responsible for 47.1% of them. Mean burnt body surface was 18% and the most affected body areas were chest and limbs. First- and second-degree burns were observed in 64.4% of the cases. Secondary infection and surgical procedures occurred in 6.5% and 45.0% of the patients, respectively. Mean length of hospital stay was 9.8 days. The mortality rate was 1.6%. Conclusions: Preschool children were the main victims of burns occurring at home, representing the largest contingent of hospitalizations due to this cause in individuals aged < 18 years. It is important to develop strategies to alert parents and general society through educational programs and preventive campaigns. PMID:25479846

Bone markers during acute burn care: Relevance to clinical practice?

PubMed

Rousseau, Anne-Françoise; Damas, Pierre; Delanaye, Pierre; Cavalier, Etienne

2017-02-01

Bone changes are increasingly described after burn. How bone markers could help to detect early bone changes or to screen burn patients at higher risk of demineralization is still not made clear. We performed an observational study assessing the changes in serum bone markers after moderate burn. Adults admitted in the first 24h following burn extended on >10% body surface area were included. Serum levels of collagen type 1 cross-linked C-telopeptide (CTX), tartrate-resistant acid phosphatase 5b (TRAP), type 1 procollagen N-terminal (P1NP) and bone alkaline phosphatase (b-ALP) were measured at admission and every week during the first month. Data are expressed as median [min-max]. Bone markers were measured in 20 patients: 18 men, 2 women (including one post-menopausal). Age was 46 [19-86] years old, burn surface area reached 15 [7-85] %. Twelve patients completed the study. All biomarkers mainly remained into normal ranges during evolution. A huge variability was observed regarding biomarkers evolution. Patient's evolution was not linear and could fluctuate from a decrease to an increase of blood concentrations. There was not necessarily a consistency between the two formation or the two resorption markers. Variations observed between two consecutive measurements were lesser than the accepted critical difference in almost one third of the cases. Considering available data, role and interest of bone markers in management of burn related bone disease remain unclear. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

A lateral tarsorrhaphy with forehead hitch to pre-empt and treat burns ectropion with a contextual review of burns ectropion management

PubMed Central

Lymperopoulos, Nikolaos S; Jordan, Daniel J; Jeevan, Ranjeet; Shokrollahi, Kayvan

2016-01-01

Introduction: Facial burns around the eyes and eyelid ectropion can lead to corneal exposure, irritation, dryness, epiphora, infection or visual loss. We undertook a review of the published articles describing management of eyelid burns as well as methods to treat or prevent ectropion. We describe early experience of a surgical technique that we have found to mitigate ectropion in facial burns with peri-ocular involvement. Materials and methods: Two illustrative cases with our surgical technique is described from our experience of three cases. We reviewed the literature using the PubMed and EMBASE databases using the search terms ‘burn’ and ‘ectropion’. Results: The literature review produced a total of 17 relevant papers. Treatment options for eyelid burns were varied and were invariably level 4 or 5 evidence. Various techniques were used to treat eyelid burns including the use of a full thickness skin graft with or without concurrent scar contracture release but also use of a local flap reconstruction with or without a tissue expander or release of the underlying muscle. Other techniques included canthoplasty, Z-plasty, forehead flaps, fat transfer, and tarsorrhaphy with full thickness skin grafting. In general, the focus of articles was therapeutic and reconstructive rather than pre-emptive/preventative management. Procedure: We describe our early experience of a novel technique for temporary lateral tarsorrhaphy with forehead hitch which protexts the globe and counters the scar- and gravity-related ectropic effects on the lower eyelids. Discussion: Facial burns pose a difficult problem to the burn surgeon, especially when the eyelids are affected, both directly or indirectly. The optimal surgical management of eyelid burns remains unclear and the literature base lies mainly in the domain of case series. We review the literature on this subject and tabulate our findings and also describe our contribution to this area with a method of lateral and lower lid elevator that we have found valuable. PMID:29799558

Charring temperatures are driven by the fuel types burned in a peatland wildfire

PubMed Central

Hudspith, Victoria A.; Belcher, Claire M.; Yearsley, Jonathan M.

2014-01-01

Peatlands represent a globally important carbon store; however, the human exploitation of this ecosystem is increasing both the frequency and severity of fires on drained peatlands. Yet, the interactions between the hydrological conditions (ecotopes), the fuel types being burned, the burn severity, and the charring temperatures (pyrolysis intensity) remain poorly understood. Here we present a post-burn assessment of a fire on a lowland raised bog in Co. Offaly, Ireland (All Saints Bog). Three burn severities were identified in the field (light, moderate, and deeply burned), and surface charcoals were taken from 17 sites across all burn severities. Charcoals were classified into two fuel type categories (either ground or aboveground fuel) and the reflectance of each charcoal particle was measured under oil using reflectance microscopy. Charcoal reflectance shows a positive relationship with charring temperature and as such can be used as a temperature proxy to reconstruct minimum charring temperatures after a fire event. Resulting median reflectance values for ground fuels are 1.09 ± 0.32%Romedian, corresponding to estimated minimum charring temperatures of 447°C ± 49°C. In contrast, the median charring temperatures of aboveground fuels were found to be considerably higher, 646°C ± 73°C (3.58 ± 0.77%Romedian). A mixed-effects modeling approach was used to demonstrate that the interaction effects of burn severity, as well as ecotope classes, on the charcoal reflectance is small compared to the main effect of fuel type. Our findings reveal that the different fuel types on raised bogs are capable of charring at different temperatures within the same fire, and that the pyrolysis intensity of the fire on All Saints Bog was primarily driven by the fuel types burning, with only a weak association to the burn severity or ecotope classes. PMID:25566288

Clinical effectiveness, quality of life and cost-effectiveness of Flaminal® versus Flamazine® in the treatment of partial thickness burns: study protocol for a randomized controlled trial.

PubMed

Rashaan, Zjir M; Krijnen, Pieta; van den Akker-van Marle, M Elske; van Baar, Margriet E; Vloemans, Adrianus F P; Dokter, Jan; Tempelman, Fenike R H; van der Vlies, Cees H; Breederveld, Roelf S

2016-03-05

Partial thickness burns are painful, difficult to manage and can have a negative effect on quality of life through scarring, permanent disfigurement and loss of function. The aim of burn treatment in partial thickness burns is to save lives, stimulate wound healing by creating an optimumly moist wound environment, to have debriding and analgesic effects, protect the wound from infection and be convenient for the patient and caregivers. However, there is no consensus on the optimal treatment of partial thickness wounds. Flaminal® and Flamazine® are two standard treatment options that provide the above mentioned properties in burn treatment. Nevertheless, no randomized controlled study has yet compared these two common treatment modalities in partial thickness burns. Thus, the aim of this study is to evaluate the clinical effectiveness, quality of life and cost-effectiveness of Flaminal® versus Flamazine® in the treatment of partial thickness burns. In this two-arm open multi-center randomized controlled trial, 90 patients will be randomized between Flaminal® and Flamazine® and followed for 12 months. The study population will consist of competent or temporarily non-competent (because of sedation and/or intubation) patients, 18 years of age or older, with acute partial thickness burns and a total body surface area (TBSA) of less than 30 %. The main study outcome is time to complete re-epithelialization (greater than 95 %). Secondary outcome measures include need for grafting, wound colonization/infection, number of dressing changes, pain and anxiety, scar formation, health-related quality of life (HRQoL), and costs. This study will contribute to the optimal treatment of patients with partial thickness burn wounds and will provide evidence on the (cost-)effectiveness and quality of life of Flaminal® versus Flamazine® in the treatment of partial thickness burns. Netherlands Trial Register NTR4486 , registered on 2 April 2014.

Anxiety, depression and PTSD-related symptoms in spouses and close relatives of burn survivors: When the supporter needs to be supported.

PubMed

Bond, Suzie; Gourlay, Catherine; Desjardins, Alexandra; Bodson-Clermont, Paule; Boucher, Marie-Ève

2017-05-01

The aim of the study was to assess the prevalence of anxiety, depression and PTSD-related symptoms reported by spouses and close relatives of adult burn survivors. Potential associations between these symptoms and variables such as the severity of the burn were also explored. Participants were spouses (n=31) and close relatives (n=25) of hospitalized patients with acute burns. Anxiety and depression symptoms were assessed by the Hospital Distress Anxiety and Depression Scale and PTSD-related symptoms by the Modified PTSD Symptom Scale at both admission to and discharge from the burn unit. At admission, 77% of spouses and 56% of close relatives of burn patients reported anxiety, depression or PTSD-related symptoms in the clinical range. While spouses had higher scores than close relatives on symptom measures, significant differences were only established for anxiety symptoms (p<.02). A significant effect was found for gender, with women reporting more anxiety (p=.01) and depression (p=.02) symptoms than men. Results also showed a main effect for time, with anxiety (p<.0001), depression (p<.0001) and PTSD-related (p<.0001) symptoms being higher at admission than at discharge. Variables associated with the index patient, such as total body surface area burned, length of stay, number of ventilated days, facial burns, or level of care at admission, were not associated with outcome measures. Spouses and close relatives of burn survivors showed high levels of psychological distress in the first few days following admission, and more than a quarter still reported symptoms in the clinical range at discharge. Our analysis points to the need to offer psychological support and guidance to family members so that they can in turn provide effective support to the burn survivor. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

[An epidemiological investigation of pediatric patients under 14 with large area burns: a multicenter study].

PubMed

Cheng, W F; Zhao, D X; Shen, Z A; Zhang, H Y; Tu, J J; Yuan, Z Q; Duan, P; Song, G D

2017-02-14

Objective: To investigate and evaluate the epidemiological characteristics of patients under 14 with large area burns in China. Methods: Data of pediatric patients aged 0-14yr with ≥30% total body surface area (TBSA) burned admitted into 106 burn centers in the mainland of China in 2014 were retrieved. The children were divided into three age groups: 0-3, 4-6 and 7-14 years according to the age. Information of age, gender, time of burn injury, causes of burns, admission time, prehospital emergency care of burn wound, burn area, inhalation injuries, the case fatality rate and length of hospital stay were collected for analysis. Results: Of the 486 cases included, 285 (58.6%) were boys and 201 (41.4%) were girls. The mean age of the children was (3.4±2.8) years. Children under 3 years old accounted for 67.5% of all the cases. 271 of the burn injuries (55.8%) occurred from April through August. Scalds and flames were the main causes of burns, which were the causes of 394 cases (81.1%) and 71 cases (14.6%), respectively. The burn injuries resulted from scalds and flames accounted for 89.6% and 7.3%, 70.8% and 21.9%, 51.6% and 41.9% in the age group of 0-3, 4-6 and 7-14 years respectively. The distribution of burn etiology in different age groups differed significantly (χ(2)=21.239, 59.442, 7.333, all P <0.01). Most of the patients (57.8%) were admitted within 2 hours after injury. However, when it came to the pre-hospital emergency management of burn wound, 164 patients (33.7%) did not use any drug or wound dressing, whereas the wound area of 236 patients (48.6%) were treated improperly with toothpaste, soy sauce, eggs or other non-standard disposal. The mean TBSA area of the patients was (42.1±14.5)%, while 288 (59.3%) of the patients suffered full thickness burns with mean TBSA of (24.5±17.9)%. The case fatality rate (CFR) was 4.1%, and the CFR of patients complicated with inhalation injury was significantly higher than those without ( P <0.01). The average length of stay for pediatric burn patients was (52.3±40.2) days. Conclusions: Children under 3 years old are important target population of severe burns. Scald is the most common type of burns, while the proportion of flames increases as age goes up. Most patients are likely to get clinical treatment in time, however, the pre-hospital emergency burn care is not satisfying at present.

Air pollutant emissions from rice straw open field burning in India, Thailand and the Philippines.

PubMed

Gadde, Butchaiah; Bonnet, Sébastien; Menke, Christoph; Garivait, Savitri

2009-05-01

Rice is a widely grown crop in Asia. China (30%) and India (21%) contribute to about half of the world's total rice production. In this study, three major rice-producing countries in Asia are considered, India, Thailand and the Philippines (the later two contributing 4% and 2% of the world's rice production). Rice straw is one of the main field based residues produced along with this commodity and its applications vary widely in the region. Although rice production practises vary from one country to another, open burning of straw is a common practice in these countries. In this study, an approach was followed aiming at (a) determining the quantity of rice straw being subject to open field burning in those countries, (b) congregating pollutant specific emissions factors for rice straw burning, and (c) quantifying the resulting air pollutant emissions. Uncertainties in the results obtained as compared to a global approach are also discussed.

on the clinical validity of the maslach burnout inventory and the burnout measure.

PubMed

Schaufeli, W B; Bakker, A B; Hoogduin, K; Schaap, C; Kladler, A

2001-09-01

Abstract Current knowledge about burnout suffers from a healthy worker bias since only working - and thus relatively healthy - employees have been investigated. The main objective of this study is to examine - for the first time among employees who sought psychological treatment - the validity of the two most widely used burnout instruments; the Maslach Burnout Inventory (MBI) and the Burnout Measure (BM). Two groups were distinguished: a "burned out" group (n = 71) that suffers from work-related neurasthenia (according to ICD-10 criteria), and a "non-burned out" group (n = 68). Results show that: (1) the validity of the three-factor structure of the MBI and the BM is confirmed; (2) burnout can partly be differentiated from other mental syndromes (e.g., anxiety and depression); and (3) two MBI-scales (Emotional Exhaustion and Depersonalization) and one BM-scale (Exhaustion) are able to discriminate between burned out and non-burned out employees. The practical implications of these results are discussed.

Air Emissions and Health Benefits from Using Sugarcane Waste as a Cellulosic Ethanol Feedstock

NASA Astrophysics Data System (ADS)

Tsao, C.; Campbell, E.; Chen, Y.; Carmichael, G.; Mena-Carrasco, M.; Spak, S.

2010-12-01

Brazil, as the largest ethanol exporter in the world, faces rapid expansion of ethanol production due to the increase of global biofuels demand. Current production of Brazilian sugarcane ethanol causes significant air emissions mainly from the open burning phase of agriculture wastes (i.e. sugarcane straws and leaves) resulting in potential health impacts. One possible measure to avoid undesired burning practices is to increase the utilization of unburned sugarcane residues as a feedstock for cellulosic ethanol. To explore the benefits of this substitution, here we first apply a bottom-up approach combining agronomic data and life-cycle models to investigate spatially and temporally explicit emissions from sugarcane waste burning. We further quantify the health benefits from preventing burning practices using the CMAQ regional air quality model and the BenMAP health benefit analysis tool adapted for Brazilian applications. Furthermore, the health impacts will be converted into monetary values which provide policymakers useful information for the development of cellulosic ethanol.

Fundamental Combustion Processes of Particle-Laden Shear Flows in Solid Fuel Ramjets

DTIC Science & Technology

1990-05-17

permitted observation of the high- intensity , near- surface flame zone. The intensity of the near-surface flame was so strong that it overpowered the light ... intensity of the 100 watt tungsten-halogen lamp used as the schlieren system light source. Figure 9a shows the burning of a 10/40/50 B/Mg/PTFE...rf five millivo’ts from the photodiode), an aorupt increase in light emission, and maximum light intensity . As the heat flux increases, the time for

Feasibility studies of in-situ coal gasification in the Warrior coal field. Quarterly report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Douglas, G.W.; McKinley, M.D.

1979-03-01

Laboratory studies on a research combustor were used in an attempt to determine the length of oxidation and reduction zones. Unfortunately the buoyant effects of the heated gases caused the burn to proceed along the upper portion of the horizontal combustor. This made the interpretation of uncertain value. Methods of measuring the thermal conductivity and chemical reactivity of coke are discussed. A bibliography of the physical and chemical properties of coke is appended. (LTN)

Effect of Intense Sound Waves on a Stationary Gas Flame

NASA Technical Reports Server (NTRS)

Hahnemann, H; Ehret, L

1950-01-01

Intense sound waves with a resonant frequency of 5000 cycles per second were imposed on a stationary propane-air flame issuing from a nozzle. In addition to a slight increase of the flame velocity, a fundamental change both in the shape of the burning zone and in the flow pattern could be observed. An attempt is made to explain the origin of the variations in the flame configuration on the basis of transition at the nozzle from jet flow to potential flow.

[Burns in adolescents].

PubMed

Ortiz Rodríguez, R; Domínguez Amillo, E; Soto Beauregard, C; Díaz González, M; López Gutiérrez, J C; Ros Mar, Z; Tovar Larrucea, J A

2012-04-01

The aim of this study was to know the epidemiology of burns in teenagers. Burn patients over 11 years old admitted in our Institution in the last 10 years were included. Etiology, burn size, hospital stay, quirurgical interventions and long term sequelae were registered. One thousand and eight patients were admitted, 89 were over 11 years (8.8%), 70.7% were boys and 29.3% girls. Fire was the principal agent in 58 cases (65.1%), due to fireworks in 13 (22.4%), alcohol in 7 (12%), explosion of flammable containers (spray) in 4 (6.8%) and gasoline in 3 (5.2%). Fireworks injuries and spray explosions affected face and hand in 88% cases. The median hospital stay was 8 days after admission (1 to 90). 83.1% required surgical treatment with mean of 1.8 +/- 1.4 interventions and 21.3% had long-term sequelaes that required at least one surgical intervention. Fire is the main cause of burns in adolescents. Fireworks injuries represented a quarter of that lesions, and highlights paint spray explosions as new causative agents. Considering the high morbidity in this age group, with permanent functional and aesthetic sequelae, prevention campaigns are needed to reduce such accidents.

Therapeutic Options in Idiopathic Burning Mouth Syndrome: Literature Review

PubMed Central

Miziara, Ivan; Chagury, Azis; Vargas, Camila; Freitas, Ludmila; Mahmoud, Ali

2014-01-01

Introduction Burning mouth syndrome (BMS) is characterized by a burning sensation in the tongue, palate, lips, or gums of no well-defined etiology. The diagnosis and treatment for primary BMS are controversial. No specific laboratory tests or diagnostic criteria are well established, and the diagnosis is made by excluding all other possible disorders. Objective To review the literature on the main treatment options in idiopathic BMS and compare the best results of the main studies in 15 years. Data Synthesis We conducted a literature review on PubMed/MEDLINE, SciELO, and Cochrane-BIREME of work in the past 15 years, and only selected studies comparing different therapeutic options in idiopathic BMS, with preference for randomized and double-blind controlled studies. Final Comments Topical clonazepam showed good short-term results for the relief of pain, although this was not presented as a definitive cure. Similarly, α-lipoic acid showed good results, but there are few randomized controlled studies that showed the long-term results and complete remission of symptoms. On the other hand, cognitive therapy is reported as a good and lasting therapeutic option with the advantage of not having side effects, and it can be combined with pharmacologic therapy. PMID:25992157

Inverse problems, non-roundness and flat pieces of the effective burning velocity from an inviscid quadratic Hamilton-Jacobi model

NASA Astrophysics Data System (ADS)

Jing, Wenjia; Tran, Hung V.; Yu, Yifeng

2017-05-01

The main goal of this paper is to understand finer properties of the effective burning velocity from a combustion model introduced by Majda and Souganidis (1994 Nonlinearity 7 1-30). Motivated by results in Bangert (1994 Calculus Variations PDE 2 49-63) and applications in turbulent combustion, we show that when the dimension is two and the flow of the ambient fluid is either weak or very strong, the level set of the effective burning velocity has flat pieces. Due to the lack of an applicable Hopf-type rigidity result, we need to identify the exact location of at least one flat piece. Implications on the effective flame front and other related inverse type problems are also discussed.

Estimates of biomass burning emissions in tropical Asia based on satellite-derived data

NASA Astrophysics Data System (ADS)

Chang, D.; Song, Y.

2009-09-01

Biomass burning in tropical Asia emits large amounts of trace gases and particulate matters into the atmosphere, which has significant implications for atmospheric chemistry and climatic change. In this study, emissions from open biomass burning over tropical Asia were evaluated during seven fire years from 2000-2006 (1 April 2000-31 March 2007). Burned areas were estimated from newly published 1-km L3JRC and 500-m MODIS burned area products (MCD45A1). Available fuel loads and emission factors were assigned for each vegetation type in a GlobCover characterisation map, and fuel moisture content was taken into account when calculating combustion factors. Over the whole period, both burned areas and fire emissions clearly showed spatial and seasonal variations. The L3JRC burned areas ranged from 31 165 km2 in fire year 2005 to 57 313 km2 in 2000, while the MCD45A1 burned areas ranged from 54 260 km2 in fire year 2001 to 127 068 km2 in 2004. Comparisons of L3JRC and MCD45A1 burned areas with ground-based measurements and other satellite information were constructed in several major burning regions, and results suggested that MCD45A1 performed better in most areas than L3JRC did although with a certain degree of underestimation of burned forest areas. The average annual L3JRC-based emissions were 125, 12, 0.98, 1.91, 0.11, 0.89, 0.044, 0.022, 0.42, 3.40, and 3.68 Tg yr

Mutagenicity and polycyclic aromatic hydrocarbons associated with extractable organic matter from airborne particles ⩽10 μm in southwest Mexico City

NASA Astrophysics Data System (ADS)

Villalobos-Pietrini, Rafael; Amador-Muñoz, Omar; Waliszewski, Stefan; Hernández-Mena, Leonel; Munive-Colín, Zenaida; Gómez-Arroyo, Sandra; Bravo-Cabrera, José Luis; Frías-Villegas, Alejandro

A year-long sampling and analysis of 24 h airborne particles equal to or less than 10 μm (PM 10) was conducted in Southwest (SW) Mexico City in 1998. The amount of airborne PM 10 and its extractable organic matter (EOM) were highly correlated. The year 1998 was particularly dry with many fires, and higher values of PM 10 and EOM were obtained in the fire period (February-May) compared to the without fire period (January, June-December). The indirect-acting mutagenicity ( Salmonella typhimurium strain TA98 with mammalian metabolic activation, S9) did not correlate with the monthly concentrations of PM 10 and EOM, while the direct-acting mutagenicity (strains TA98 and YG1021, without mammalian metabolic activation) did correlate. The highest monthly mutagenic potency of TA98+S9 and of TA98-S9 were registered in May which correspond to the fire period, while for YG1021 the highest was in December, a without fire month. The highest TA98+S9/TA98-S9 ratios appeared from April to September (with the exception of June), indicating that emission of the direct mutagens occurred in the rest of the year (the coldest months), and December showed the highest mutagenicity of YG1021. The correlation of this mutagenicity with the number of ground-based inversions indicated a greater emissions of nitroarenes in the coldest months emitted mainly by vehicular traffic as shown by the correlation between YG1021 with CO and with NO 2. We did not find a correlation in the EOM of the complex mixtures between TA98+S9 and the total concentration of polycyclic aromatic hydrocarbons (PAH) nor between TA98+S9 and specific PAH. The analysis by gas chromatography/mass spectrometry indicated the presence of retene, a PAH found in the fire period and considered a softwood burning marker. The concentrations of fluoranthene and benz[ a]anthracene correlated with that of retene and with the burned area; they were the only PAH that presented significant differences between the periods with fire and without fire, showing that these compounds could have a similar origin. Benzo[ ghi]perylene, coronene and indeno[1,2,3 -cd]pyrene were the most abundant PAH of the 17 analyzed in SW Mexico City, indicating that the main emission source for PAH in the airborne particle phase in this zone were vehicles with the combustion of gasoline and diesel rather than wood burning. The mean concentrations for most PAH were higher during the fire period, except for perylene and coronene, suggesting that the fires were not the emission source for these two last PAH.

Amniotic membrane traps and induces apoptosis of inflammatory cells in ocular surface chemical burn

PubMed Central

Liu, Ting; Zhai, Hualei; Xu, Yuanyuan; Dong, Yanling; Sun, Yajie; Zang, Xinjie

2012-01-01

Purpose Severe chemical burns can cause necrosis of ocular surface tissues following the infiltration of inflammatory cells. It has been shown that amniotic membrane transplantation (AMT) is an effective treatment for severe chemical burns, but the phenotypes of cells that infiltrate the amniotic membrane and the clinical significance of these cellular infiltrations have not previously been reported. The present work studies the inflammation cell traps and apoptosis inducing roles of the amniotic membrane after AMT in patients with acute chemical burns. Methods A total of 30 patients with acute alkaline burns were classified as having either moderate or severe burns. In all participants, AMT was performed within one week of his/her injury. After 7–9 days, the transplanted amniotic membranes were removed. Histopathological and immunohistochemical techniques were used for the examination and detection of infiltrating cells, and tests for the expression of CD (cluster of differentiation)15, CD68, CD3, CD20, CD57, CD31, CD147, and CD95 (Fas) were performed. A TUNEL (TdT-mediated dUTP nick end labeling) assay was used to confirm apoptosis of the infiltrating cells. Three patients with herpes simplex-induced keratitis who had undergone AMT to treat persistent epithelium defects were used as a control group. Amniotic membrane before transplantation was used as another control. Results After amniotic membrane transplantation, the number of infiltrating cells in patients with severe burns was significantly higher than in patients with moderate burns or in control patients (p<0.05). Among the severe burns patients, CD15 and CD68 were widely expressed in the infiltrating cells, and CD3, CD20, and CD57 were only found in a small number of cells. Occasionally, CD31-positive cells were found in the amniotic membranes. More cells that were CD147, Fas, and TUNEL positive were found in patients with severe burns than in patients with moderate burns or in control patients. Conclusions Neutrophils and macrophages were the main cells that had infiltrated into the amniotic membrane during the acute phase of healing from a chemical burns. AMT can trap different inflammatory cells and induce apoptosis of inflammatory cells in acute ocular chemical burns. PMID:22876141

The effects of crude oil and remediation burning on three clones of smooth cordgrass (Spartina alterniflora Loisel.)

USGS Publications Warehouse

Smith, D.L.; Proffitt, C.E.

1999-01-01

Burning has been employed as an oil spill remediation technique in coastal marshes, even though the combined and interactive effects of soil and burning on vegetation are poorly understood. Variation among clones of perennial marsh grasses in response to these perturbations is not known. We performed a greenhouse experiment designed to assess the effects of Venezuelan crude oil alone and of oil followed by burning on three clonal genets of Spartina alterniflora. The fully-crossed 6-mo experiment involved five dosages of oil (0 l m-2, 4 l m-2, 8 l m-2, 16 l m-2, and 24 l m-2) and two burn treatments (burned or unburned) applied to ramets from three clones. All oil-only dosages reduced survival, but burning after oiling (oil + burn treatments) increased survival relative to oil-only groups in all except the highest two oil dosages. Higher oil-only treatments also reduced ramet densities and inhibited density increases over 6 mo. Burning after treatment with the 16 l m-2 oil concentration allowed increased production of new ramets, but burning exacerbated the negative impacts on ramet density at the oil concentration of 24 l m-2. At some intermediate oil dosages, burning remediated the negative effects of oil on aboveground biomass production and growth in height. There was a significant effect of oil-only treatments on numbers of flowering ramets produced, in which two clones responded with decreased flower production and one exhibited increased flowering. There was no main effect of oil + burn on flowering. There were significant among-clones differences in all response variables to one or both treatments. Our experiment demonstrates that burning of oiled S. alterniflora marshes may have little measurable effect at low levels of Venezuelan crude oil, can remediate the effects of oil at intermediate oil concentrations, but can increase the negative impacts at high concentrations of oil. These results indicate that oil spills have the potential to adversely affect genetic diversity in S. alterniflora populations by eliminating some sensitive clonal variants or changing the relative dominance of genets. These results suggest certain clones may be better suited for phytoremediation or restoration planting following oil spills.

Our initial learning curve in the enzymatic debridement of severely burned hands-Management and pit falls of initial treatments and our development of a post debridement wound treatment algorithm.

PubMed

Schulz, A; Perbix, W; Shoham, Y; Daali, S; Charalampaki, C; Fuchs, P C; Schiefer, J

2017-03-01

Excisional surgical debridement (SD) is still the gold standard in the treatment of deeply burned hands, though the intricate anatomy is easily damaged. Previous studies demonstrated that enzymatic debridement with the bromelain debriding agent NexoBrid ® (EDNX) is more selective and thus can preserve viable tissue with excellent outcome results. So far no method paper has been published presenting different treatment algorithms in this new field. Therefore our aim was to close this gap by presenting our detailed learning curve in EDNX of deeply burned hands. We conducted a single-center prospective observational clinical trial treating 20 patients with deeply burned hands with EDNX. Different anaesthetic procedures, debridement and wound treatment algorithms were compared and main pitfalls described. EDNX was efficient in 90% of the treatments though correct wound bed evaluation was challenging and found unusual compared to SD. Post EDNX surprisingly the majority of the burn surface area was found overestimated (18 wounds). Finally we simplified our process and reduced treatment costs by following a modified treatment algorithm and treating under plexus anaesthesia bedside through a single nurse and one burn surgeon solely. Suprathel ® could be shown to be an appropriate dressing for wound treatment after EDNX. Complete healing (less 5% rest defect) was achieved at an average of day 28. EDNX in deep burned hands is promising regarding handling and duration of the treatment, efficiency and selectivity of debridement, healing potential and early rehabilitation. Following our treatment algorithm EDNX can be performed easily and even without special knowledge in burn wound depth evaluation. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

The effect of levamisole on mortality rate among patients with severe burn injuries

PubMed Central

Fatemi, Mohammad Javad; Salehi, Hamid; Akbari, Hossein; Alinejad, Faranak; Saberi, Mohsen; Mousavi, Seyed Jaber; Soltani, Majid; Taghavi, Shahrzad; Payandan, Hossein

2013-01-01

Background: Burn injuries are one of the main causes of mortality and morbidity throughout the world and burn patients have higher chances for infection due to their decreased immune resistance. Levamisole, as an immunomodulation agent, stimulates the immune response against infection. Materials and Methods: This randomized clinical trial was conducted in Motahari Burn Center, Tehran, Iran. Patients who had second- or third-degree burn with involvement of more than 50% of total body surface area (TBSA) were studied. The levamisole group received levamisole tablet, 100 mg per day. Meantime, both the levamisole and control groups received the standard therapy of the Burn Center, based on a standard protocol. Then, the outcome of the patients was evaluated. Results: 237 patients entered the study. After excluding 42 patients with inhalation injury, electrical and chemical burns, and the patients who died in the first 72 h, 195 patients remained in the study, including 110 patients in the control group and 85 in the treatment group. The mean age of all patients (between 13 to 64 years) was 33.29 ± 11.39 years (Mean ± SD), and it was 33.86 ± 11.45 years in the control group and 32.57 ± 11.32 years in the treatment group. The mean percentage of TBSA burn was 64.50 ± 14.34 and 68.58 ± 14.55 for the levamisole and control groups, respectively, with the range of 50-100% and 50-95% TBSA. The mortality rate was 68 (61.8%) patients in the control group and 50 (58.8%) patients in the treatment group (P = 0.8). Conclusion: According to this study, there was no significant relationship between improvement of mortality and levamisole consumption. PMID:24381625

Moisturisers in scar management following burn: A survey report.

PubMed

Klotz, Tanja; Kurmis, Rochelle; Munn, Zachary; Heath, Kathryn; Greenwood, John

2017-08-01

Scar management is a recognised key component of rehabilitation following burn. Moisturising often combined with massage is commenced once healing tissue has gained sufficient strength to tolerate surface friction, with the aim being to hydrate the dry scar. The studies on various moisturisers and creams provide some guidance on moisturiser selection, but many are inconclusive. This survey aimed to determine the current expert opinion regarding moisturiser recommendations, including the basis for these recommendations, across the burns community. A brief web-based survey was distributed to burn therapists via mailing lists of the Australian and New Zealand Burn Association (ANZBA), and American Burn Association (ABA) 'Occupational and Physical Therapist Burn Special Interest Group'. The fifty three respondents indicated that there were 29 different moisturisers commonly recommended in practice. Three main themes were indicated as influencing recommendations for moisturiser: the perceived effects on the scar/skin (48%); the general properties of the moisturiser (38%); the ingredients (14%). Therapists reported that the principle stimuli determining their recommendations were patient feedback and the choice of the previous burn therapist in their service. Many were also guided by medical staff, pharmacists and sales representatives. Only three respondents were able to provide citations for published evidence supporting their recommendations. There is a paucity of evidence currently to support optimal moisturiser choice. This survey demonstrates that conflicting opinions are held on the ideal moisturiser brand, properties and ingredients. The recommendations made are based on low level evidence. Further research is required to inform clinicians which moisturiser to recommend to their clients. An ideal moisturiser should be one that is conducive to scar maturation, non- or minimally irritant, prevent skin drying, minimise transepidermal water loss and have no negative effect on barrier function. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Measuring the impact of a burns school reintegration programme on the time taken to return to school: A multi-disciplinary team intervention for children returning to school after a significant burn injury.

PubMed

Arshad, Sira N; Gaskell, Sarah L; Baker, Charlotte; Ellis, Nicola; Potts, Jennie; Coucill, Theresa; Ryan, Lynn; Smith, Jan; Nixon, Anna; Greaves, Kate; Monk, Rebecca; Shelmerdine, Teresa; Leach, Alison; Shah, Mamta

2015-06-01

Returning to school can be a major step for burn-injured children, their family, and staff and pupils at the receiving school. Previous literature has recognised the difficulties children may face after a significant injury and factors that may influence a successful reintegration. A regional paediatric burns service recognised that some patients were experiencing difficulties in returning to school. A baseline audit confirmed this and suggested factors that hindered or facilitated this process, initiating the development of a school reintegration programme (SRP). Since the programme's development in 2009, it has been audited annually. The aim of this paper was to evaluate the impact of the SRP by presenting data from the 2009 to 2011 audits. For the baseline audit, the burn care team gathered information from clinical records (age, gender, total body surface area burned (TBSA), skin grafting and length of stay) and telephone interviews with parents and teachers of the school returners. For the re-audits, the same information was gathered from clinical records and feedback questionnaires. Since its introduction, the mean length of time from discharge to return to school has dropped annually for those that opted into the programme, when compared to the baseline by 62.3% (53 days to 20 days). Thematic analysis highlights positive responses to the programme from all involved. Increased awareness and feeling supported were amongst the main themes to emerge. Returning to school after a significant burn injury can be challenging for all involved, but we hypothesise that outreach interventions in schools by burns services can have a positive impact on the time it takes children to successfully reintegrate. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

Savings and load reaps passive solar dividends

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1979-06-01

A wood-burning fireplace is the main backup heating system at the Friendship Federal Savings and Loan office in Butler, Pennsylvania. The solar design consists of a passive system in which a concrete block wall serves as the energy collector for the building. A 14-square meter skylight over part of the main banking lobby provides additional solar energy. (MCW)

Thermo-Chemical Conversion of Microwave Activated Biomass Mixtures

NASA Astrophysics Data System (ADS)

Barmina, I.; Kolmickovs, A.; Valdmanis, R.; Vostrikovs, S.; Zake, M.

2018-05-01

Thermo-chemical conversion of microwave activated wheat straw mixtures with wood or peat pellets is studied experimentally with the aim to provide more effective application of wheat straw for heat energy production. Microwave pre-processing of straw pellets is used to provide a partial decomposition of the main constituents of straw and to activate the thermo-chemical conversion of wheat straw mixtures with wood or peat pellets. The experimental study includes complex measurements of the elemental composition of biomass pellets (wheat straw, wood, peat), DTG analysis of their thermal degradation, FTIR analysis of the composition of combustible volatiles entering the combustor, the flame temperature, the heat output of the device and composition of the products by comparing these characteristics for mixtures with unprocessed and mw pre-treated straw pellets. The results of experimental study confirm that mw pre-processing of straw activates the thermal decomposition of mixtures providing enhanced formation of combustible volatiles. This leads to improvement of the combustion conditions in the flame reaction zone, completing thus the combustion of volatiles, increasing the flame temperature, the heat output from the device, the produced heat energy per mass of burned mixture and decreasing at the same time the mass fraction of unburned volatiles in the products.

Combustion mechanism of double-base propellant containing nitrogen heterocyclic nitroamines (II): The temperature distribution of the flame and its chemical structure

NASA Astrophysics Data System (ADS)

Yan, Qi-Long; Song, Zhen-Wei; Shi, Xiao-Bing; Yang, Zhi-Yuan; Zhang, Xiao-Hong

2009-03-01

In order to evaluate the actual pros and cons in the use of new nitroamines for solid rocket applications, the combustion properties of double-base propellants containing nitrogen heterocyclic nitroamines such as RDX, TNAD, HMX and DNP are investigated by means of high-speed photography technique, Non-contact wavelet-based measurement of flame temperature distribution. The chemical reactions in different combustion zone which control the burning characteristics of the double-base propellant containing nitrogen heterocyclic nitroamines were systematically investigated and descriptions of the detailed thermal decomposition mechanisms from solid phase to liquid phase or to gas phase are also included. It was indicated that the thermodynamic phase transition consisting of both evaporation and condensation of NC+NG, HMX, TNAD, RDX and DNP, are considered to provide a complete description of the mass transfer process in the combustion of these double-base propellants, and the combustion mechanisms of them are mainly involved with the oxidation mechanism of the NO 2, formaldehyde (CH 2O) and hydrogen cyanide (HCN). The entire oxidation reaction rate might be dependent on the pressure of the combustion chamber and temperature of the gas phase.

Climatic pacing of Mediterranean fire histories from lake sedimentary microcharcoal

NASA Astrophysics Data System (ADS)

Turner, R.; Roberts, N.; Jones, M. D.

2008-10-01

The microcharcoal content (particles < 180 µm) of overlapping sedimentary sequences from two crater lake basins in central Turkey are used to reconstruct the regional fire history of the East Mediterranean oak-grass parkland zone from the Last Glacial Maximum to the present-day. These results are correlated with stable isotope and pollen data from the same cores in order to assess the changing role of climate, vegetation and human activity in landscape burning. This indicates that climatically-induced variation in biomass availability was the main factor controlling the timing of regional fire activity during the Last Glacial-Interglacial climatic transition, and again during Mid-Holocene times, with fire frequency and magnitude increasing during wetter climatic phases. Spectral analysis of the Holocene part of the record from Eski Acıgöl indicates significant cyclicity with a periodicity of ~ 1500 years that may be linked with large-scale climate forcing. Although proto-agricultural societies were established in this region as early as 10,000 years ago, it is only during the last two to three millennia that the pacing of wildfire cycles appears to have become decoupled from climate and linked instead to human-induced changes in land cover and fuel load availability.

[Researches in immunological responses after burn injury in China].

PubMed

Peng, Dai-zhi

2008-10-01

For five decades it has been recognized that severe burn injury may precipitate in marked alterations in immune function, resulting in life-threatening systemic infections, sepsis, multiple organ failure, and even death. Extensive and deep burns exert widespread and profound impacts on various cells and molecules of the immune system. The general characteristics of abnormal immune responses following major burns are hyperinflammatory response and hypoimmune response of innate and adaptive immunity. These are recognized as postburn immune dysfunction (PID). The stress reaction, massive necrotic tissue, shock, infection, malnutrition and various therapeutic procedures after burns alter the microenvironment of the immune cells and molecules in which they reside, and consequently result in the changes in immune cells and their secretions in quantity and/or activity, and also aberrant signal transduction in different immune cells. These events constitute the cellular and molecular bases in the pathogenesis of PID. The main clinical consequences of PID include tissue damages and increased susceptibility to opportunistic pathogens caused by refractory inflammation and suppressed adaptive immunity. In order to decrease the morbidity of these lethal complications, efforts to improve the immune dysfunction after burn injury have been made not only at the integral level of etiological factors, but also at the cellular and molecular levels of its mechanisms. In this review, all these above-mentioned aspects of PID are comprehensively discussed.

Internet-based information and support program for parents of children with burns: A randomized controlled trial.

PubMed

Sveen, Josefin; Andersson, Gerhard; Buhrman, Bo; Sjöberg, Folke; Willebrand, Mimmie

2017-05-01

The aim of the study was to evaluate the feasibility and effects of an internet-based information and self-help program with therapist contact for parents of children and adolescents with burns. The program aimed to reduce parents' symptoms of general and posttraumatic stress. Participants were parents of children treated for burns between 2009-2013 at either of the two specialized Swedish Burn centers. Sixty-two parents were included in a two-armed, randomized controlled trial with a six-week intervention group and a wait-list control group, including a pre and post-assessment, as well as a 3 and 12-month follow-up. The intervention contained psychoeducation, exercises and homework assignments, and the intervention group received weekly written feedback from a therapist. The main outcome was stress (post-traumatic stress, general stress and parental stress). The program had a beneficial effect on posttraumatic stress in the short term, but did not affect general stress or parental stress. The parents rated the program as being informative and meaningful, but some of them thought it was time-consuming. The program has the potential to support parents of children with burns. The intervention is easily accessible, cost-effective and could be implemented in burn care rehabilitation. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.