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Tan, X. Gary, and Peter Matic. "Simulation of Cumulative Exposure Statistics for Blast Pressure Transmission Into the Brain." Military Medicine 185, Supplement_1 (January 2020): 214–26. http://dx.doi.org/10.1093/milmed/usz308.
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Abstract Introduction This study develops and demonstrates an analysis approach to understand the statistics of cumulative pressure exposure of the brain to repetitive blasts events. Materials and Methods A finite element model of blast loading on the head was used for brain model biomechanical responses. The cumulative pressure exposure fraction (CPEF), ranging from 0.0 to 1.0, was used to characterize the extent and repetition of high pressures. Monte Carlo simulations were performed to generate repetitive blast cumulative exposures. Results The blast orientation effect is as influential as the blast overpressure magnitudes. A 75° (from the side) blast orientation can produce CPEF values exceeding traumatic brain injury pressure thresholds >0.95 while, for the same blast overpressure, a 0° (front) blast orientation results in a CPEF <0.25. Monte Carlo results for different sequences reflecting notional operational and training environments show that both mean values and standard deviations of CPEF reach the statistically equilibrium state at a finite value of n exposures for each sequence. Conclusions Statistical convergence of the brain pressure response metrics versus number of blasts for different exposures characterizes the transitions from “low” to “high” number of blasts and quantitatively highlights the differences between operational and training exposures.
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Yim, Won Cheol, and John C. Cushman. "Divide and Conquer (DC) BLAST: fast and easy BLAST execution within HPC environments." PeerJ 5 (June 22, 2017): e3486. http://dx.doi.org/10.7717/peerj.3486.
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Bioinformatics is currently faced with very large-scale data sets that lead to computational jobs, especially sequence similarity searches, that can take absurdly long times to run. For example, the National Center for Biotechnology Information (NCBI) Basic Local Alignment Search Tool (BLAST and BLAST+) suite, which is by far the most widely used tool for rapid similarity searching among nucleic acid or amino acid sequences, is highly central processing unit (CPU) intensive. While the BLAST suite of programs perform searches very rapidly, they have the potential to be accelerated. In recent years, distributed computing environments have become more widely accessible and used due to the increasing availability of high-performance computing (HPC) systems. Therefore, simple solutions for data parallelization are needed to expedite BLAST and other sequence analysis tools. However, existing software for parallel sequence similarity searches often requires extensive computational experience and skill on the part of the user. In order to accelerate BLAST and other sequence analysis tools, Divide and Conquer BLAST (DCBLAST) was developed to perform NCBI BLAST searches within a cluster, grid, or HPC environment by using a query sequence distribution approach. Scaling from one (1) to 256 CPU cores resulted in significant improvements in processing speed. Thus, DCBLAST dramatically accelerates the execution of BLAST searches using a simple, accessible, robust, and parallel approach. DCBLAST works across multiple nodes automatically and it overcomes the speed limitation of single-node BLAST programs. DCBLAST can be used on any HPC system, can take advantage of hundreds of nodes, and has no output limitations. This freely available tool simplifies distributed computation pipelines to facilitate the rapid discovery of sequence similarities between very large data sets.
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Schomer, Paul. "Attention to rattles and a non-equal-energy model are required for proper sonic boom assessment." Journal of the Acoustical Society of America 153, no. 3_supplement (March 1, 2023): A275. http://dx.doi.org/10.1121/10.0018829.
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This paper is concerned with the assessment of community response to sonic booms or blasts. It summarizes and analyzes the totality of results from studies in the English language that used real booms or blasts, with subjects in real buildings. In acoustics, we are accustomed to noise sources operating in accordance with the equal-energy principle (a 1 dB increase in amplitude is equivalent to a 1 dB increase in duration). The results show that rattles are the most important attribute contributing to the annoyance engendered by sonic booms/blasts, and that the process is not equal-energy. Rather, the equivalent annoyance generated by a change of 1 dB in the C-weighted boom or blast amplitude is equal to about a 1.5 to 2 dB change in the boom or blast duration where the exchange rate is defined to be 1 over these changes in duration, 0.67 and 0.5, respectively. The exchange rates found in several sonic boom/blast noise studies are given, and as an example, the exchange rate for the historical Oklahoma City study is calculated. The conclusions from the Long-Term Sonic Boom Noise Environments study are examined in relation to the range of exchange rates found in other boom/blast studies.
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Ghimire, Krishna Hari, Hira Kaji Manandhar, Madhav Prasad Pandey, Bal Krishna Joshi, Surya Kanta Ghimire, Ajaya Karkee, Suk Bahadur Gurung, Netra Hari Ghimire, and Devendra Gauchan. "Multi-Environment Screening of Nepalese Finger Millet Landraces against Blast Disease [Pyricularia grisea (Cooke) Sacc.)]." Journal of Nepal Agricultural Research Council 8 (May 9, 2022): 35–52. http://dx.doi.org/10.3126/jnarc.v8i.44874.
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Three hundred finger millet genotypes (295 landraces from 54 districts and five released varieties) were evaluated for leaf, finger, and neck blast resistance under natural epiphytotic conditions across three hill locations in Nepal, namely Kabre, Dolakha (1740m); Vijaynagar, Jumla (2350 m); and Khumaltar, Lalitpur (1360 m) during the summer seasons of 2017 and 2018. The highest incidence of leaf, neck, and finger blast was observed at Lalitpur, followed by Dolakha and Jumla, whereas the overall disease incidence was higher in 2018 compared to 2017. Combined analysis over environments revealed non-significant differences among accessions for leaf blast, but the difference was highly significant for neck and finger blast. Correlation analysis suggested that there was a strong positive correlation between neck blast and finger blast (r = 0.71), leaf blast (seedling stage) and neck blast (r = 0.68), and leaf blast (seedling stage) and finger blast (r = 0.58) diseases. Among 300 accessions, 95 had lower scores for finger blast, 30 for neck blast, and 74 for leaf blast than the score of Kabre Kodo-2, the latest released variety in Nepal. Genotypes NGRC04798, NGRC03478, NGRC05765, NGRC03539, NGRC06484, NGRC01458, NGRC01495 and NGRC01597 were found the resistant genotypes for finger blast (2.1-2.3) and neck blast (1.5-2.3) based on pooled mean scores. This study shows the variable reactions of finger millet genotypes against blast disease in various environments and reports the promising landraces having field resistance to leaf, finger, and neck blast, which ultimately serve as important donors for blast resistance in finger millet breeding.
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Petrescu, Valentin, Florian Popescu, and Alina Gligor. "Blast Furnace In Engineering Education." Balkan Region Conference on Engineering and Business Education 1, no. 1 (August 15, 2014): 127–30. http://dx.doi.org/10.2478/cplbu-2014-0027.
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AbstractUsing blended learning method, Blast Furnace subject was analysed inside the DidaTec Project. The analysed factors were the quality of presentation, quantity of information per page and human – computer interaction. The analysis shows the preference of students to work with different learning environments.
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Okpala, Major Nnaemeka. "Management of Blast Ear Injuries in Mass Casualty Environments." Military Medicine 176, no. 11 (November 2011): 1306–10. http://dx.doi.org/10.7205/milmed-d-10-00318.
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Ehrgott Jr., John Q., Stephen A. Akers, Jon E. Windham, Denis D. Rickman, and Kent T. Danielson. "The Influence of Soil Parameters on the Impulse and Airblast Overpressure Loading above Surface-Laid and Shallow-Buried Explosives." Shock and Vibration 18, no. 6 (2011): 857–74. http://dx.doi.org/10.1155/2011/672850.
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The dynamic airblast, fragmentation, and soil ejecta loading environments produced by the detonation of surface-laid and shallow-buried mines are major threats to lightweight military vehicles. During the past several years, the US Army has focused considerable attention on developing improved methods for predicting the below-vehicle environment from these threats for use by vehicle/armor analysts; thereby, improving the survivability of these platforms. The US Army Engineer Research and Development Center recently completed the first year of a three-year effort to experimentally and numerically quantify the blast and fragment loading environments on vehicles due to surface and subsurface mine and IED detonations. As part of this research effort, a series of experiments was conducted to quantify the effects of soil parameters on the aboveground blast environments produced by the detonation of aboveground bottom-surface-tangent, buried top-surface-tangent, and shallow-buried 2.3-kg (5-lb) Composition C4 charges. The experiments were conducted using three different well characterized soils; 10.8% air-filled-voids (AFV) silty sand, 5.4% AFV clay, and 29.8% AFV poorly graded sand. The combined aboveground loads due to airblast and soil debris were measured by an impulse measurement device. The near-surface airblast overpressure was quantified by a series of side-on measurements above the charges at one elevation and three radial distances. This paper summarizes and compares the results of the experimental program with emphasis on defining the effect of soil parameters on the aboveground blast environment.
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Ramasamy, Arul, Adam M. Hill, Spyros Masouros, Iain Gibb, Anthony M. J. Bull, and Jon C. Clasper. "Blast-related fracture patterns: a forensic biomechanical approach." Journal of The Royal Society Interface 8, no. 58 (December 2010): 689–98. http://dx.doi.org/10.1098/rsif.2010.0476.
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Improved protective measures and medical care has increased the survivability from battlefield injuries. In an attempt to reduce the debilitating consequences of blast injury, understanding and mitigating the effects of explosion on the extremities is key. In this study, forensic biomechanical analyses have been applied to determine mechanisms of injury after the traumatic event. The aims of this study were (i) to determine which effects of the explosion are responsible for combat casualty extremity bone injury in two distinct environments, namely open, free-field (open group), and in vehicle or in cover (enclosed group), and (ii) to determine whether patterns of combat casualty bone injury differed between environments. Medical records of casualties admitted to a military hospital in Afghanistan were reviewed over a six-month period. Explosive injuries have been sub-divided traditionally into primary, secondary and tertiary effects. All radiographs were independently reviewed by a military radiologist, a team of military orthopaedic surgeons and a team of academic biomechanists, in order to determine ‘zones of injury’ (ZoIs), and their related mechanisms. Sixty-two combat casualties with 115 ZoIs were identified. Thirty-four casualties in the open group sustained 56 ZoIs; 28 casualties in the enclosed group sustained 59 ZoIs. There was no statistical difference in mean ZoIs per casualty between groups ( p = 0.54). There was a higher proportion of lower limb injuries in the enclosed group compared with the open group ( p < 0.05). Of the casualties in the open group, 1 ZoI was owing to the primary effects of blast, 10 owing to a combination of primary and secondary blast effects, 23 owing to secondary blast effects and 24 owing to tertiary blast effects. In contrast, tertiary blast effects predominated in the enclosed group, accounting for 96 per cent of ZoIs. These data clearly demonstrate two distinct injury groups based upon the casualties' environment. The enclosed environment appears to attenuate the primary and secondary effects of the explosion. However, tertiary blast effects were the predominant mechanism of injury, with severe axial loading to the lower extremity being a characteristic of the fractures seen. The development of future mitigation strategies must focus on reducing all explosion-related injury mechanisms. Integral to this process is an urgent requirement to better understand the behaviour of bone in this unique environment.
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Lee, Chang-Yull, Jin-Young Jung, and Se-Min Jeong. "Active Vibration Suppression of Stiffened Composite Panels with Piezoelectric Materials under Blast Loads." Applied Sciences 10, no. 1 (January 4, 2020): 387. http://dx.doi.org/10.3390/app10010387.
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Transient responses of stiffened panels with piezoelectric sensors and actuators are studied under normal blast loads. The air vehicles could be exposed to blast pulses generated by an explosion or shock-wave disturbances. Thus, active vibration suppression of the vehicles is important under blast loadings. The structural model is designed as a laminated composite panel with lead zirconate titanate (PZT) piezoceramic layers embedded on both top and bottom surfaces. A uniformly distributed blast load is assumed over the whole of the panel surface. The first-order shear deformation theory of plate is adopted, and the extended Hamilton’s principle is applied to derive the equations of motions. The numerical model is verified by the comparison with previous data. Using linear quadratic regulator (LQR) control algorithm, vibration characteristics and dynamic responses are compared. As piezoelectric patches are attached on the whole of the surface, the effect of the stiffener’s location is studied. Furthermore, the influences of the patch’s positions are also investigated through subjection to the blast wave. From various results, in order to get the best control performances, the research aims to find the optimum position of sensor and actuator pairs that is most effective under blast load environments.
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Dvořák, Richard, Petr Hrubý, and Libor Topolář. "Characterization of Carbonatation Rate of Alkali-Activated Blast Furnace Slag in Various Environments." Solid State Phenomena 325 (October 11, 2021): 40–46. http://dx.doi.org/10.4028/www.scientific.net/ssp.325.40.
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Carbonatation represents one of the potential degradation processes whose can negatively affect the service life of constructions based on the inorganic binders. The carbonatation depth of the constructions when exposed to various environments is significantly dependent on the existing conditions. The most crucial parameters are the partial pressure of carbon dioxide and humidity. There were selected four environments for the deposition of samples made of the alkali-activated blast furnace slag mortars (exterior, interior, water and CO2 chamber) in this study. These types of environments guarantee the variation of desired parameters influencing the carbonatation rate. The progress of carbonatation was evaluated with a selected technique in time intervals of 28; 56 and 84 days of the sample's exposition to the selected environments. The characterization was done using the destructive techniques (compressive and flexural strength, phenolphthalein method) as well as the non-destructive one like the Impact-Echo or the Ultrasound time passage measurement. The combination of these techniques allows to determine and evaluate the progress of carbonation without the destructive testing of the samples which is necessary for the real applications of these materials.
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Mohottige, Nimasha Weerasingha, Chengqing Wu, and Hong Hao. "Characteristics of Free Air Blast Loading Due to Simultaneously Detonated Multiple Charges." International Journal of Structural Stability and Dynamics 14, no. 04 (April 2, 2014): 1450002. http://dx.doi.org/10.1142/s0219455414500023.
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Extensive research has been conducted to investigate the characteristics of blast load due to single charge explosion, including numerical simulations and experimental blast tests in both unconfined and confined environments. Further, available guidelines for blast resistant design such as UFC-3-340-02 (2008) and ASCE 59-11 (2011) provide details to predict blast loads on a structure subjected to single charge explosion. However, blast load characteristics due to multiple charge explosions are poorly discussed in available literature. In this paper, commercially available Hydrocode, AUTODYN is calibrated for single charge explosions. Based on a comparison between numerical simulation and UFC prediction, correction factors for peak reflected pressure and positive reflected impulse as a function of charge weight, scaled distance and mesh size of the numerical model are proposed to minimize the errors in simulations. The calibrated AUTODYN model is then used to conduct parametric studies to investigate the effects of charge weight, scaled distance, number of charges and distance between the charges on the characteristics of free air blast load due to simultaneous detonated multiple charges. Numerical simulation results are used to derive analytical formulas for predictions of peak reflected pressure ratio and positive reflected impulse ratio between single and multiple explosions. The discussion is made on characteristics of free air blast load due to simultaneous detonated multiple charges.
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Aune, Vegard, Folco Casadei, Georgios Valsamos, Magnus Langseth, and Tore Børvik. "A Shock Tube Used to Study the Dynamic Response of Blast-Loaded Plates." Proceedings 2, no. 8 (June 28, 2018): 503. http://dx.doi.org/10.3390/icem18-05395.
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This study aims to a better understanding of the performance of a shock tube used to produce blast loading in controlled laboratory environments. Special focus is placed on the influence of the diaphragm failure process on the blast wave formation in the tube. Experimental observations are supported by numerical simulations in an attempt to obtain more insight into the underlying phenomena. It was found that the diaphragm failure process introduces a multi-dimensional flow field downstream the diaphragms. This is observed as a loss of directional energy in the distant flow field and therefore affects the reflected overpressure on blast-loaded plates located at the rear end of the tube. These findings provide important insight into how such a facility works, especially if the dynamic response of flexible plates is of interest.
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Flood, Ian, Bryan T. Bewick, and Emmart Rauch. "Rapid Simulation of Blast Wave Propagation in Built Environments Using Coarse-Grain Simulation." International Journal of Protective Structures 3, no. 4 (December 2012): 431–48. http://dx.doi.org/10.1260/2041-4196.3.4.431.
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Yoganandan, Narayan, Brian D. Stemper, Frank A. Pintar, Dennis J. Maiman, B. Joseph McEntire, and Valeta Carol Chancey. "Cervical spine injury biomechanics: Applications for under body blast loadings in military environments." Clinical Biomechanics 28, no. 6 (July 2013): 602–9. http://dx.doi.org/10.1016/j.clinbiomech.2013.05.007.
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Wang, Xueyan, Melissa H. Jia, Pooja Ghai, Fleet N. Lee, and Yulin Jia. "Genome-Wide Association of Rice Blast Disease Resistance and Yield-Related Components of Rice." Molecular Plant-Microbe Interactions® 28, no. 12 (December 2015): 1383–92. http://dx.doi.org/10.1094/mpmi-06-15-0131-r.
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Robust disease resistance may require an expenditure of energy that may limit crop yield potential. In the present study, a subset of a United States Department of Agriculture rice core collection consisting of 151 accessions was selected using a major blast resistance (R) gene, Pi-ta, marker and was genotyped with 156 simple sequence repeat (SSR) markers. Disease reactions to Magnaporthe oryzae, the causal agent of rice blast disease, were evaluated under greenhouse and field conditions, and heading date, plant height, paddy and brown seed weight in two field environments were analyzed, using an association mapping approach. A total of 21 SSR markers distributed among rice chromosomes 2 to 12 were associated with blast resistance, and 16 SSR markers were associated with seed weight, heading date, and plant height. Most noticeably, shorter plants were significantly correlated with resistance to blast, rice genomes with Pi-ta were associated with lighter seed weights, and the susceptible alleles of RM171 and RM6544 were associated with heavier seed weight. These findings unraveled a complex relationship between disease resistance and yield-related components.
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Sabri, Raieah Saiyedah, Mohd Y. Rafii, Mohd Razi Ismail, Oladosu Yusuff, Samuel C. Chukwu, and Nor’Aishah Hasan. "Assessment of Agro-Morphologic Performance, Genetic Parameters and Clustering Pattern of Newly Developed Blast Resistant Rice Lines Tested in Four Environments." Agronomy 10, no. 8 (July 29, 2020): 1098. http://dx.doi.org/10.3390/agronomy10081098.
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Multi-environmental yield trial is very vital in assessing newly developed rice lines for its adaptability and stability across environments especially prior to release of the newly developed variety for commercial cultivation. The growth performance and phenotypic variability of these genotypes are the combination of environment, genotype and genotype by environment (G×E) interaction factors. Thus, evaluation creates an opportunity for effective selection of superior genotypes. The objectives of this study were to evaluate the newly developed blast resistant rice lines in varied environmental conditions, precisely measure the response of the advanced lines in multiple environments and classify the genotypes into groups that could serve as varieties for commercial cultivation. Genetic materials included 18 improved blast resistant rice lines and the recipient parent MR219. The total of 19 newly developed genotypes was evaluated under four varied environments in Peninsular Malaysia. The experiments were carried out using randomized complete block design (RCBD) with three replications at each environment. Data were collected on the vegetative, yield and yield component traits. Descriptive statistics (mean performance) and analysis of variance were conducted using SAS Software version 9.4. Genotypic and phenotypic coefficients, phenotypic variance component, heritability and genetic advance were also determined. Analysis of variance revealed that all traits were significantly different for genotypes except days to maturity, number of filled grains and total number of grains. Meanwhile, all the traits differed significantly for genotype × environment (G×E) except number of tillers per hill and number of panicles per hill. Low heritability (<30%) was found for all the traits. Similarly, low genetic advance was also observed for all the traits except for number of tillers per hill and number of panicles per hill. yield per hectare had significant and positive correlation with most evaluated traits except for days to flowering, days to maturity, plant height and number of unfilled grains. Cluster analysis classified the 19 evaluated genotypes into six groups. Therefore, the six clusters/groups of genotypes were recommended as varieties for commercial cultivation in Malaysia and other rice growing regions.
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Manuel, Gethin, and David Waddington. "An Heuristic Prediction Method for Managing Environmental Blast Noise Impacts." INTER-NOISE and NOISE-CON Congress and Conference Proceedings 265, no. 4 (February 1, 2023): 3797–808. http://dx.doi.org/10.3397/in_2022_0537.
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The aim of this work is to manage adverse environmental impacts from long-range blast noise. The work was carried out as part of ongoing research at the DNV Spadeadam Testing and Research site (STaR). STaR carries out crucial major hazards work including improving safety concerns within industry decarbonization sectors and government agencies. The site performs a variety of explosives testing, resulting in environmental blast noise at off-site residential locations. The site is surrounded by complex topography, with terrain featuring range-dependent ground impedance and thermal properties which in turn effects the local meteorology. While accurately modelling blast wave propagation through such environments using traditional computational methods is a computationally expensive task, the required complex and rapidly varying meteorological data are not adequately available. To address this deficiency, a data-driven heuristic method is proposed for the prediction of blast noise levels at several sensitive receivers ranging from 4-14km. The model is formed from a preliminary dataset of off-site blast noise measurements, correlated with a multivariate array of available meteorological data. A principal component analysis is used to determine the atmospheric features which are most influential to sound propagation, and predict the likely range of peak sound pressure levels expected. It is concluded that useful predictions over time scales from an hour to a number of days can be obtained for managing environmental blast noise impacts, and that further measurements of blast noise, along with further correlations with measured atmospheric conditions, could improve the performance of the model.
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Ahmed, Ash, and John Kamau. "Performance of Ternary Class F Pulverised Fuel Ash and Ground Granulated Blast Furnace Slag Concrete in Sulfate Solutions." European Journal of Engineering Research and Science 2, no. 7 (July 11, 2017): 8. http://dx.doi.org/10.24018/ejers.2017.2.7.401.
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Durability of concrete is defined as its ability to resist deterioration after it has been exposed to the environment of its intended use. This work examined the performance of combined (ternary) Pulverised Fuel Ash (PFA) and Ground Granulated Blast Furnace Slag (GGBS) concrete in sulfate solutions of sodium sulfate (Na2SO4), magnesium sulfate (MgSO4) and mixed Na2SO4 and MgSO4, as well as its performance in water absorption. Investigations were carried out on replacements that were found to have achieved the highest compressive strengths as well as on 30% replacements from a previous study. From the results obtained, it was also found that at highest compressive strengths, the ternary concrete could be used with an advantage over the individual binary concretes in MgSO4 environments, whereas at a higher replacement, the ternary concrete could be used with an advantage over individual binary specimens in Na2SO4 and MgSO4 environments. For visual observations, it was concluded that the ternary concrete could be used with an advantage over the individual binary concretes in Na2SO4 and MgSO4 environments, whereas for strength deterioration, the results showed that the ternary specimens could be used with an advantage over individual binary concretes in both the MgSO4 and the mixed sulfate solutions. Generally, the ternary specimens showed some complimentary effect from the two materials.
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Ahmed, Ash, and John Kamau. "Performance of Ternary Class F Pulverised Fuel Ash and Ground Granulated Blast Furnace Slag Concrete in Sulfate Solutions." European Journal of Engineering and Technology Research 2, no. 7 (July 11, 2017): 8–13. http://dx.doi.org/10.24018/ejeng.2017.2.7.401.
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Durability of concrete is defined as its ability to resist deterioration after it has been exposed to the environment of its intended use. This work examined the performance of combined (ternary) Pulverised Fuel Ash (PFA) and Ground Granulated Blast Furnace Slag (GGBS) concrete in sulfate solutions of sodium sulfate (Na2SO4), magnesium sulfate (MgSO4) and mixed Na2SO4 and MgSO4, as well as its performance in water absorption. Investigations were carried out on replacements that were found to have achieved the highest compressive strengths as well as on 30% replacements from a previous study. From the results obtained, it was also found that at highest compressive strengths, the ternary concrete could be used with an advantage over the individual binary concretes in MgSO4 environments, whereas at a higher replacement, the ternary concrete could be used with an advantage over individual binary specimens in Na2SO4 and MgSO4 environments. For visual observations, it was concluded that the ternary concrete could be used with an advantage over the individual binary concretes in Na2SO4 and MgSO4 environments, whereas for strength deterioration, the results showed that the ternary specimens could be used with an advantage over individual binary concretes in both the MgSO4 and the mixed sulfate solutions. Generally, the ternary specimens showed some complimentary effect from the two materials.
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Zhang, Jing, Qingxia Wang, Wannian Guo, and Longlong Li. "A Support Vector Machine Based Prediction on Sensitivity to Coal Ash Blast for Different Degrees of Deterioration." Journal of Sensors 2022 (August 8, 2022): 1–12. http://dx.doi.org/10.1155/2022/7604338.
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Coal ash blast is a potential hazard that causes serious disasters in coal mines. In explosion control, research work on coal ash sensitivity prediction is of practical importance to improve accuracy, reduce blindness of explosion protection measures, and strengthen targets. The potential and destructive characteristics of coal ash blast vary greatly from coal to coal, especially in coal mines with complex and changing environments, where the characteristics of coal ash blast show great variability under the influence of various factors. In addition, due to the lack of systematic and comprehensive understanding of the occurrence mechanism of coal ash blast, it is necessary to conduct systematic research on the occurrence mechanism of coal ash blast. Current coal ash blast sensitivity summarizes and concludes prediction methods to create reliable predictions for coal ash blast. A new general learning method, support vector machine (SVM), has been developed, which provides a unified framework for solving limited sample training problems and can better solve small sample training problems. With the purpose of determining the coal mine problem and coal ash sensitivity prediction sensitivity indicators and thresholds, the SVM method is used to set the sensitivity function of each prediction indicator, and the sensitivity of each prediction indicator for the proposed study mine is expressed quantitatively. The experimental results show that the prediction accuracy of SVM for positive and negative categories is 15.6% higher than that of BP neural network and 35.1% higher than that of Apriori algorithm. Therefore, the prediction effectiveness of the SVM algorithm is proved. Therefore, it is practical to adopt SVM method for prediction on sensitivity to coal ash blast and apply the latest statistical learning theory SVM to predict the risk of coal ash.
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Tang, Wenxin, Wei Wan, and Jiapeng Zou. "Application of High-Performance Concrete in Bridge Structures Under Extreme Environment." Highlights in Science, Engineering and Technology 51 (May 16, 2023): 126–31. http://dx.doi.org/10.54097/hset.v51i.8248.
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Bridges in extreme environments combine the mission of connecting remote areas with the challenge of surviving in harsh environments. For the high quality construction and long term application of bridges, the design and application of high-performance concrete (HPC) are researched in this paper. Firstly, the application of HPC in bridges under cold environment is studied. Based on the failure mechanism of concrete and mix ratio design of HPC in cold area, the conclusion is drawn that adding appropriate amount of diatomaceous earth materials can better adapt to cold environment. Then, what kind of HPC is suitable for bridge in coastal environment is explored. By studying the failure mechanism and mix ratio of concrete in coastal areas, it is found that adding the appropriate amount of blast-furnace slag (GGBS) can better resist the damage caused by the ocean. Finally, the working condition of HPC is defined as the construction of bridges in hot environment. The HPC was designed after consulting the difficulties of concrete pouring in hot weather. The experimental results show that adding a proper amount of fly ash can solve this problem. This study can provide a reference for using HPC to build bridges in different extreme environments.
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Shehu, E., L. Lomazzi, M. Giglio, and A. Manes. "Computational modeling of confined blast waves with focus on interaction with structures." IOP Conference Series: Materials Science and Engineering 1275, no. 1 (February 1, 2023): 012028. http://dx.doi.org/10.1088/1757-899x/1275/1/012028.
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Abstract Blast loading is a critical extreme loading condition for most engineering structures. Modeling such scenarios is challenging due to the intrinsic non-linearities. Recent numerical methods can capture the physics governing blast waves and their interaction with structures in a more accurate way than established empirical methods. This article is intended as a proof of concept that state-of-the-art CFD and FE software can be combined to set up high-fidelity uncoupled simulations. Computational fluid dynamics is exploited in this work to map the pressure field developed during a detonation reaction in a Eulerian domain. Then, such pressure time history is applied in the finite element framework to perform Lagrangian simulations. The methodology is used to compare the structural response of blast-loaded plates in fully confined environments to that in free-field scenarios. It turns out that confined blast waves are more severe than blast waves in unconfined scenarios, mainly due to the multiple reflections and residual quasi-static pressure. Moreover, on the one hand, the quasi-static pressure appears to contribute to further increasing the plate out-of-plane deflection, while on the other hand, it prevents plates from undergoing reverse buckling or oscillations around the initial equilibrium configuration. Experimental tests are required to provide further evidence about the latter contribution.
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Guo, Baolin, Chao Wang, Xianghui Ma, Ruishuang Jiang, Baomin Wang, Jifei Yan, and Hang Liu. "Research on Impermeability of Underwater Non-Dispersible Concrete in Saline Soil." Materials 15, no. 22 (November 9, 2022): 7915. http://dx.doi.org/10.3390/ma15227915.
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The permeability of different strength grades of submerged non-dispersible concrete with different granulated slag admixtures in a saline soil environment simulated by different erosion solutions was investigated. The variation patterns of the chloride ion diffusion coefficient and pore characteristics were tested using NEL and MIP. The microscopic morphology of the specimens in different erosion environments and with slag doping was observed using SEM. The results showed that the impermeability of concrete in sulfate and complex salt environments was significantly reduced. The resistance of concrete to chloride ion penetration increased with the increase in strength grade, and the Cl− diffusion coefficient of C35 was 5–30% lower than those of C30 and C25 underwater non-dispersible concrete at 360 d. Meanwhile, the admixture of granulated blast-furnace slag optimized the pore size distribution and improved the matrix compactness and permeability.
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Tran, Mien Van, Yen Thi Hai Nguyen, and Thi Nguyen Cao. "EFFECTS OF BLAST FURNACE SLAG ON CHLORIDE PERMEABILITY OF CONCRETE." Science and Technology Development Journal 15, no. 2 (June 30, 2012): 70–80. http://dx.doi.org/10.32508/stdj.v15i2.1792.
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Chloride-induced corrosion of steel reinforcement is the main cause of deterioration of reinforced concrete structures in marine environments. The penetration of chlodride ions into concrete cover that accelerates corrosion process of steel reinforcement, this affects the bearing capacity of structures. This paper investigates on chloride permeability cheracteristic of concrete using blast furnace slag in terms of chloride diffusion coefficient and chloride binding capacity. The concrete used in this research has grade of 45MPa and the slag content replacement of cement PC50 is in range of 0% - 70%. The chloride diffusion coefficient of concrete is determined by ASTM C1202 and NordTest NT Build 492. Results showed that the blast furnace slag replacement increases (from 0% to 50%), the chloride ion diffusion coeffient decreases and bound chloride content in concrete increases. It is clear to conclude that blast furnace slag can be used to replace cement PC50 in range of 30% to 40% in order to increase the resistance of concrete to chloride penetration without affecting concrete strength.
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Wang, X., M. Remotigue, Q. Arnoldus, M. Janus, E. Luke, D. Thompson, R. Weed, and G. Bessette. "High-fidelity simulations of blast loadings in urban environments using an overset meshing strategy." Shock Waves 27, no. 3 (July 14, 2016): 409–22. http://dx.doi.org/10.1007/s00193-016-0680-x.
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Wickens, Zoe. "Dry eye treatments round-up." Optician 2018, no. 8 (August 2018): 178537–1. http://dx.doi.org/10.12968/opti.2018.8.178537.
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With most working environments now demanding long hours of screen time and with air conditioning on full blast in the summer, dry eye symptoms are often difficult to escape. Zoe Wickens reports on what products are on the market to ease the pain and asks some office staff to give them a try
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Plšková, Iveta, Petr Hrubý, Libor Topolář, and Michal Matysík. "Degradation of Materials Based on Alkali-Activated Blast-Furnace Slag after Exposure to Aggressive Environments." Solid State Phenomena 325 (October 11, 2021): 131–36. http://dx.doi.org/10.4028/www.scientific.net/ssp.325.131.
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The paper summarizes partial results of a study of degradation of materials based on alkali-activated blast-furnace slag (AAS) and comparative on cement CEM III/A 32.5 R after exposure to aggressive environments. It further specifies the possibilities for utilising destructive and non-destructive techniques to determine the progress of degradation and characterizes the degree of their correlation. After 28 days of ageing in a water environment, the produced test specimens (40×40×160 mm beams) were placed in aggressive media (ammonium nitrate solutions; sodium sulfate, rotating water) and after subsequent 28, 56 and 84 days of degradation were subjected to testing. Testing comprised both a destructive form (determination of compressive strength and flexural strength) and a selected non-destructive technique (Impact-echo method). The partial outputs were supplemented by the results acquired from monitoring weight changes. In addition, the development of Ultrasonic Pulse Velocity in relation to the progress of the degradation processes was also monitored. While the exposure of both test specimens to water and sodium sulfate did not result in any significant changes, the exposure to the ammonium nitrate solution exhibited rapid signs of degradation associated with a significant reduction in functional characteristics.
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Zhang, Zeyu, Honggui Deng, Yang Liu, Qiguo Xu, and Gang Liu. "A Semi-Supervised Semantic Segmentation Method for Blast-Hole Detection." Symmetry 14, no. 4 (March 23, 2022): 653. http://dx.doi.org/10.3390/sym14040653.
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The goal of blast-hole detection is to help place charge explosives into blast-holes. This process is full of challenges, because it requires the ability to extract sample features in complex environments, and to detect a wide variety of blast-holes. Detection techniques based on deep learning with RGB-D semantic segmentation have emerged in recent years of research and achieved good results. However, implementing semantic segmentation based on deep learning usually requires a large amount of labeled data, which creates a large burden on the production of the dataset. To address the dilemma that there is very little training data available for explosive charging equipment to detect blast-holes, this paper extends the core idea of semi-supervised learning to RGB-D semantic segmentation, and devises an ERF-AC-PSPNet model based on a symmetric encoder–decoder structure. The model adds a residual connection layer and a dilated convolution layer for down-sampling, followed by an attention complementary module to acquire the feature maps, and uses a pyramid scene parsing network to achieve hole segmentation during decoding. A new semi-supervised learning method, based on pseudo-labeling and self-training, is proposed, to train the model for intelligent detection of blast-holes. The designed pseudo-labeling is based on the HOG algorithm and depth data, and proved to have good results in experiments. To verify the validity of the method, we carried out experiments on the images of blast-holes collected at a mine site. Compared to the previous segmentation methods, our method is less dependent on the labeled data and achieved IoU of 0.810, 0.867, 0.923, and 0.945, at labeling ratios of 1/8, 1/4, 1/2, and 1.
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Procházka, Lukáš, and Jana Boháčová. "Effect of Admixtures on Durability Characteristics of Fly Ash Alkali-activated Material." Emerging Science Journal 4, no. 6 (December 1, 2020): 493–502. http://dx.doi.org/10.28991/esj-2020-01247.
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This paper deals with the possibility of partial replacement of blast furnace slag with fly ash and fly ash after denitrification by SNCR method in alkali-activated materials based on granulated blast furnace slag. The aim of this paper is to verify the effect of fly ash on properties of alkali-activated materials based on blast furnace granulated slag. Frost resistance and resistance to aggressive environments, represented by demineralized water were tested. The reference mixture was based on blast furnace granulated slag activated by sodium water glass with silicate modulus of 2. Mixtures with an ash content of 10, 20, and 30% were then compared with the reference mixture. The influence of the denitrification process on fly ash and its use in mixed alkali activated materials was also compared. As a part of the experiment, alkali-activated pastes were also prepared. Infrared spectroscopy with Furier transformation was subsequently determined on these pastes. The reference mixture achieved the highest compressive strength in the experiment and the strength decreased with increasing amount of fly ash. In terms of flexural strength, the highest values were reached for mixtures with 10% slag replacement by fly ash. In the case of frost resistance, the significant increase of flexural strength, which was 50% for the reference mixture, is particularly interesting. For compressive strength, the frost resistance coefficient ranged from 0.95 to 1.00. In the case of resistance to aggressive environments, no differences were observed in the compressive strength, on the other hand, flexural strength decrease of up to 20% was detected for 10 and 20 percent replacement of slag with fly ash that did not undergo denitrification. Monitored properties did not show any negative effect of the denitrification process on fly ash properties. Infrared spectroscopy identified the main hydration product in the region of 945 cm-1which is a C-(A)-S-H gel and in combined mixtures with fly ash also N-A-S-H gel. Doi: 10.28991/esj-2020-01247 Full Text: PDF
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Melchers, Robert E., and Igor A. Chaves. "Durable Steel-Reinforced Concrete Structures for Marine Environments." Sustainability 13, no. 24 (December 11, 2021): 13695. http://dx.doi.org/10.3390/su132413695.
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Even in harsh marine environments, concrete structures reinforced with steel can show excellent long-term durability, with little or no reinforcement corrosion. Very few actual reinforced concrete (RC) structures have been closely scrutinized over many years and subject to interpretation using recent state-of-the-art understanding gained from detailed laboratory observations. Such a case is described for an 80-year-old RC structure observed annually over about 30 years in what is essentially an extraordinary long experiment. Despite very high chloride concentrations, field excavation evidence showed that reinforcement corrosion overall remains minimal, except where insufficient concrete compaction permitted air-voids to initiate quite severe, very localized corrosion even with still high concrete pH. It is possible that the use of blast furnace slag as aggregate may have assisted the observed durability. The case study supports other studies that show that it is possible to achieve long-term durable and therefore sustainable RC structures without additives and using only conventional reinforcement steels and conventional cements and aggregates. However, the potential dangers of deep narrow cracking extending to the reinforcement and the potentially deleterious effects of alkali–aggregate reactivity of some aggregates needs to be considered.
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Martel, Richard, Luc Trépanier, Marc-André Lavigne, Benoît Lévesque, Guy Sanfaçon, Patrick Brousseau, and Pierre Auger. "Carbon monoxide poisoning associated with blasting operations close to underground enclosed spaces. Part 2. Special working procedures to minimize CO migration." Canadian Geotechnical Journal 41, no. 3 (June 1, 2004): 383–91. http://dx.doi.org/10.1139/t04-002.
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Carbon monoxide (CO) produced by blasting operations in civil engineering works in residential environments can migrate fair distances in the surrounding fractured bedrock and underground infrastructures in the blast area and can then infiltrate enclosed spaces. Poisoning of workers and people in general exposed to an emission of CO produced by explosives has occurred many times. Special working procedures must be developed to minimize the risk of poisoning. Three different procedures were tested in the field where the geologic conditions (slate confined with more than 0.5 m of clayey till) were favourable for CO migration. The first procedure tested aimed to minimize CO production and migration by changing the usual explosive type and the sequence of blasting, excavating and embanking the debris, and installing vents in the surrounding rock. This method did not have a significant effect on CO migration. The second method aimed to mitigate the CO produced by excavating the overburden before drilling, placing blast mats, excavating the broken rock after each blast, and changing the sequence of blasting. This procedure was efficient and safe. The third method consisted of pumping the interstitial air in the broken rock with a vacuum truck immediately after each blast. This method was a good alternative but requires monitoring of the exhaust air and was not as efficient and reliable as the excavation method.Key words: carbon monoxide, blasting, poisoning, enclosed spaces, remediation, house.
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Webster, Claire Elizabeth, J. Clasper, I. Gibb, and S. D. Masouros. "Environment at the time of injury determines injury patterns in pelvic blast." Journal of the Royal Army Medical Corps 165, no. 1 (December 22, 2018): 15–17. http://dx.doi.org/10.1136/jramc-2018-000977.
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The use of explosives by terrorists, or during armed conflict, remains a major global threat. Increasingly, these events occur in the civilian domain, and can potentially lead to injury and loss of life, on a very large scale. The environment at the time of detonation is known to result in different injury patterns in casualties exposed to blast, which is highly relevant to injury mitigation analyses. We describe differences in pelvic injury patterns in relation to different environments, from casualties that presented to the deployed UK military hospitals in Iraq and Afghanistan. A casualty on foot when injured typically sustains an unstable pelvic fracture pattern, which is commonly the cause of death. These casualties die from blood loss, meaning treatment in these should focus on early pelvic haemorrhage control. In contrast, casualties injured in vehicle present a different pattern, possibly caused by direct loading via the seat, which does not result in pelvic instability. Fatalities in this cohort are from injuries to other body regions, in particular the head and the torso and who may require urgent neurosurgery or thoracotomy as life-saving interventions. A different strategy is therefore required for mounted and dismounted casualties in order to increase survivors.
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Yoganandan, Narayan, Frank A. Pintar, Michael Schlick, John R. Humm, Liming Voo, Andrew Merkle, and Michael Kleinberger. "Vertical accelerator device to apply loads simulating blast environments in the military to human surrogates." Journal of Biomechanics 48, no. 12 (September 2015): 3534–38. http://dx.doi.org/10.1016/j.jbiomech.2015.06.008.
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Procházka, Lukáš, Jana Boháčová, and Barbara Vojvodíková. "Effect of Admixtures on Durability and Physical-Mechanical Properties of Alkali-Activated Materials." Materials 15, no. 6 (March 8, 2022): 2010. http://dx.doi.org/10.3390/ma15062010.
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The results of ground granulated blast furnace slag (GGBS) tests in alkali-activated systems show that, with its use, it is possible to produce promising materials with the required properties. Unfortunately, GGBS is becoming a scarce commodity on the market, so the effort is to partially replace its volume in these materials with other secondary materials, while maintaining the original properties. This paper focuses on a comparison of two basic types of mixtures. The first mixture was prepared only from ground granulated blast furnace slag (GGBS) and the second type of mixture was prepared with admixtures, where the admixtures formed a total of 30% (15% of the replacement was fly ash after denitrification—FA, and 15% of the replacement was cement by-pass dust—CBPD). These mixtures were prepared with varying amounts of activator and tested. The experiment monitored the development of strength over time and the influence of different types of aggressive environments on the strength characteristics. Thermal analysis and FTIR were used in the experiment to determine the degradation products. The paper provides an interesting comparison of the resistance results of different composites in aggressive environments and at the same time an evaluation of the behavior of individual mixtures in different types of aggressive environment. After 28 days of maturation, the highest strengths were obtained with mixtures with the lowest doses of activator. The difference in these compressive strengths was around 25% in favor of the mixtures with only GGBS; in the case of flexural strength, this difference was around 23%. The largest decreases in strength were achieved in the XA3 environment. This environment contains the highest concentration of sulfate ions according to the EN 206-1 standard. The decreases in compressive strength were 40–45%, compared to the same old reference series. The surface degraded due to sulfate ions. Calcium sulphate dihydrate was identified by FTIR, thermal analysis and SEM as a degradation product.
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Wang, Xueyan, Yulin Jia, Yeshi Wamishe, Melissa H. Jia, and Barbara Valent. "Dynamic Changes in the Rice Blast Population in the United States Over Six Decades." Molecular Plant-Microbe Interactions® 30, no. 10 (October 2017): 803–12. http://dx.doi.org/10.1094/mpmi-04-17-0101-r.
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Rice blast disease caused by Magnaporthe oryzae is one of the most destructive diseases of rice. Field isolates of M. oryzae rapidly adapt to their hosts and climate. Tracking the genetic and pathogenic variability of field isolates is essential to understand how M. oryzae interacts with hosts and environments. In this study, a total of 1,022 United States field isolates collected from 1959 to 2015 were analyzed for pathogenicity toward eight international rice differentials. A subset of 457 isolates was genotyped with 10 polymorphic simple sequence repeat (SSR) markers. The average polymorphism information content value of markers was 0.55, suggesting that the SSR markers were highly informative to capture the population variances. Six genetic clusters were identified by both STRUCTURE and discriminant analysis of principal components methods. Overall, Nei’s diversity of M. oryzae in the United States was 0.53, which is higher than previously reported in a world rice blast collection (0.19). The observed subdivision was associated with collection time periods but not with geographic origin of the isolates. Races such as IC-17, IE-1, and IB-49 have been identified across almost all collection periods and all clusters; races such as IA-1, IB-17, and IH-1 have a much higher frequency in certain periods and clusters. Both genomic and pathogenicity changes of United States blast isolates were associated with collection year, suggesting that hosts are a driving force for the genomic variability of rice blast fungus.
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Hung, Tran Quang, Do Minh Duc, and Tran Minh Tu. "Thermally induced vibration analysis of sandwich beam with metal foam core subjected to blast loading by a framework of two-unknown higher-order beam theory." IOP Conference Series: Materials Science and Engineering 1289, no. 1 (August 1, 2023): 012006. http://dx.doi.org/10.1088/1757-899x/1289/1/012006.
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Abstract Vibrational characteristics of a sandwich beam in thermal environments subjected to blast pressure are investigated in this paper. The sandwich beam is composed of two isotropic skins and an open-cell metal foam core with either uniform or symmetric distribution of internal pores. The pressure of blast loading is modelled by Friedlander’s equation. A two-unknown higher-order beam theory combined with Hamilton’s principle is used to establish the governing equations. Navier-type solution and Newmark-beta method are applied to deal with the governing equation and obtain the dynamic responses. The efficiency and accuracy of the present study are examined through numerical examples. Effects of temperature-dependent material properties, porosity coefficient, core-to-skin thickness ratio, length-to-height ratio, and structural damping on the natural frequencies and dynamic deflection of the sandwich beam are investigated in detail.
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Rutter, Barbara, Hailong Song, Ralph G. DePalma, Graham Hubler, Jiankun Cui, Zezong Gu, and Catherine E. Johnson. "Shock Wave Physics as Related to Primary Non-Impact Blast-Induced Traumatic Brain Injury." Military Medicine 186, Supplement_1 (January 1, 2021): 601–9. http://dx.doi.org/10.1093/milmed/usaa290.
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ABSTRACT Introduction Blast overpressure exposure, an important cause of traumatic brain injury (TBI), may occur during combat or military training. TBI, most commonly mild TBI, is considered a signature injury of recent combat in Iraq and Afghanistan. Low intensity primary blast-induced TBI (bTBI), caused by exposure to an explosive shock wave, commonly leaves no obvious physical external signs. Numerous studies have been conducted to understand its biological effects; however, the role of shock wave energy as related to bTBI remains poorly understood. This report combines shock wave analysis with established biological effects on the mouse brain to provide insights into the effects of shock wave physics as related to low intensity bTBI outcomes from both open-air and shock tube environments. Methods Shock wave peak pressure, rise time, positive phase duration, impulse, shock velocity, and particle velocity were measured using the Missouri open-air blast model from 16 blast experiments totaling 122 mice to quantify physical shock wave properties. Open-air shock waves were generated by detonating 350-g 1-m suspended Composition C-4 charges with targets on 1-m elevated stands at 2.15, 3, 4, and 7 m from the source. Results All mice sustained brain injury with no observable head movement, because of mice experiencing lower dynamic pressures than calculated in shock tubes. Impulse, pressure loading over time, was found to be directly related to bTBI severity and is a primary shock physics variable that relates to bTBI. Discussion The physical blast properties including shock wave peak pressure, rise time, positive phase duration, impulse, shock velocity, and particle velocity were examined using the Missouri open-air blast model in mice with associated neurobehavioral deficits. The blast-exposed mice sustained ultrastructural abnormalities in mitochondria, myelinated axons, and synapses, implicating that primary low intensity blast leads to nanoscale brain damage by providing the link to its pathogenesis. The velocity of the shock wave reflected back from the target stand was calculated from high-speed video and compared with that of the incident shock wave velocity. Peak incident pressure measured from high sample rate sensors was found to be within 1% of the velocity recorded by the high-speed camera, concluding that using sensors in or close to an animal brain can provide useful information regarding shock velocity within the brain, leading to more advanced knowledge between shock wave physics and tissue damage that leads to bTBIs.
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Netpakdee, Chaiwat, Sittiwut Mathasiripakorn, Arthit Sribunrueang, Sompong Chankaew, Tidarat Monkham, Siwaret Arikit, and Jirawat Sanitchon. "QTL-Seq Approach Identified Pi63 Conferring Blast Resistance at the Seedling and Tillering Stages of Thai Indigenous Rice Variety “Phaladum”." Agriculture 12, no. 8 (August 5, 2022): 1166. http://dx.doi.org/10.3390/agriculture12081166.
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Rice blast (BL) caused by Magnaporthe oryzae is a fungal disease causing significant yield losses in rice production worldwide. To overcome the breakdown of resistance by the rapid adaptation of pathogens, identifying resistance (R) genes or QTLs in indigenous rice, which harbors the R genes that co-evolved with the local pathogen race, is necessary. In this study, a recombinant inbred line (RIL) population derived from a cross between RD6 and Phaladum (PLD) was used to map quantitative trait loci (QTL) for BL resistance through a QTL-seq approach. A single QTL (qBLchr4) associated with BL resistance at the seedling and maximum tillering stages was mapped on the long arm of chromosome 4. Five genes, LOC_Os04g0616600, LOC_Os04g0617900 (OsGLP4-1), LOC_Os04g0619600 (OsRLCK161), LOC_Os04g0620800 (Pi63), and LOC_Os04g0621500, were considered the candidate genes representing qBLchr4. Subsequently, the Kompetitive Allele-Specific PCR (KASP) markers specific for the SNP variant and position of each gene were designed for validation in the mapping population. These markers showed the high phenotypic variance explained (PVE) values in all testing methods and/or environments, signifying the major effect of qBLchr4. Among these markers, the Pi63-KASP marker explained the highest and most stable phenotypic variation across all testing methods and/or environments, with 84.18%, 80.34%, and 23.43% in the upland short row (USR) method, Sila environment, and Mueang environment, respectively. Therefore, Pi63 was suggested to be the strongest candidate gene. These results represent the potential utility of future BL resistance breeding and/or pyramiding using marker-assisted selection (MAS).
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Lentscher, Jessica A., Joshua C. Combs, Karrie Walker, Christopher M. Young, and Rebecca Chason. "Postdeployment Fertility Challenges and Treatment in the Modern Era." Seminars in Reproductive Medicine 37, no. 05/06 (September 2019): 239–45. http://dx.doi.org/10.1055/s-0040-1713430.
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AbstractCurrent war-fighting environments have shifted dramatically over the past decade, and with this change, new types of injuries are afflicting American soldiers. Operative Enduring Freedom and Operation Iraqi Freedom have noted an increased use of sophisticated improvised explosive devices by adversaries. Injuries not frequently seen in previous conflict are dismounted complex blast injuries, which involve multiple proximal amputations, pelvic fractures, and extensive perineal wounds. Thus, an unforeseen consequence of the decreased mortality rate after these complex blast injuries is a new wave of U.S. service members facing the challenges of recovering from the catastrophic amputations and genitourinary injuries. New applications of sperm retrieval methods may be used in these specific populations, as they recover and wish to purse family-building goals. Spinal cord injuries, traumatic brain injuries, and considerations unique to the female soldier are explored in this review of urologic care in wounded veterans.
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Xu, Cheng, Jiehao Xu, Jiating Liu, Yu Chen, Øystein Evensen, Hetron Mweemba Munang’andu, and Guoying Qian. "Human adenovirus penton base and encapsidation sequences detected in Pelodiscus sinensis by next generation sequencing." Future Virology 14, no. 7 (July 2019): 453–60. http://dx.doi.org/10.2217/fvl-2019-0056.
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The Chinese soft-shelled turtle ( Pelodiscus sinensis) has become one of the leading cultured organisms in China and South East Asia. The objectives of the present study were to use next generation sequencing to identify viral genomes present in liver tissues from Chinese soft-shelled turtle in China. BLAST analysis of viral sequences from liver samples showed high homology with the human adenovirus (HAdV) penton base and encapsidation proteins. This homology points to possible existence of HAdV in freshwater environments used for the culture of soft-shelled turtles. Therefore, our findings merit further investigations to determine possible contamination of HAdV in aquaculture environments and the possible role of the Chinese soft-shelled turtle in transmitting HAdV to humans.
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Anougba, Bossoma Danielle, Assiénin Hauverset N'guessan, Kla Konan, N’Klo François Hala, and Kolo Yeo. "Inventory of refuge plants of Recilia mica Kramer (Homoptera, Cicadellidae), blast disease vector in oil palm nursery (Elaeis guineensis Jacq." International Journal of Biological and Chemical Sciences 14, no. 2 (May 10, 2020): 317–32. http://dx.doi.org/10.4314/ijbcs.v14i2.2.
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Blast is the most important disease in nursery of palm tree in West Africa. The mycoplasm responsible of this disease is transmitted by the vector Recilia mica KRAMER (Homoptera, Cicadellidae). The aim of this study was to determine R. mica KRAMER plants reservoirs. To achieve this objective, an inventory of the flora frequented by this insect was carried out around two selected plots including a palm tree nursery and a plantation. In total, 14 plants were identified around the nursery and 15 plants around the plantation. Some plants have been registered in both environments. Plants considered refuges for R. mica in this study were Digitaria horizontalis, Pueraria phaseoloides, Panicum maximum, Oldemlandia herbacea, Ageratum conyzoides, Ipomea eriocarpa, Eleusine indica. Furthermore, this study showed that the Recilia mica frequents more plants of the Poaceae family compared to other plant families. This study should be continued to study the reproductive biology of R. micaKeywords: Oil Palm tree, Blast disease, Recilia mica, refuge plants.
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Komljenović, Miroslav, Nataša Džunuzović, and Violeta Nikolić. "Resistance to external sulfate attack - Comparison of two alkali-activated binders." MATEC Web of Conferences 163 (2018): 06001. http://dx.doi.org/10.1051/matecconf/201816306001.
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Durability of binders, mortars and concretes in aggressive environments is of crucial importance for their commercial application. In this paper the resistance to external sulfate attack of two different alkaliactivated binders (AABs), based either on blast furnace slag (BFS) or fly ash/blast furnace slag (FA/BFS) blend, was compared with two different commercially available Portland cement (CEM II) blended either with BFS or with FA and BFS. Comparison of sulfate resistance was based on compressive strength testing (the loss of strength) of mortar samples exposed to sodium sulfate attack up to 180 days and samples cured under controlled conditions for the same period of time. Furthermore, the evolution of microstructure of alkali-activated binders and pH of sodium silicate solution during testing were also analyzed. Despite different gel chemistry being involved, both alkali-activated binders based either on BFS or FA/BFS blend showed excellent resistance to external sulfate attack and even better than selected Portland cements tested under the same experimental conditions.
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Zamkovaya, Tatyana, Jamie S. Foster, Valérie de Crécy-Lagard, and Ana Conesa. "A network approach to elucidate and prioritize microbial dark matter in microbial communities." ISME Journal 15, no. 1 (September 22, 2020): 228–44. http://dx.doi.org/10.1038/s41396-020-00777-x.
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AbstractMicrobes compose most of the biomass on the planet, yet the majority of taxa remain uncharacterized. These unknown microbes, often referred to as “microbial dark matter,” represent a major challenge for biology. To understand the ecological contributions of these Unknown taxa, it is essential to first understand the relationship between unknown species, neighboring microbes, and their respective environment. Here, we establish a method to study the ecological significance of “microbial dark matter” by building microbial co-occurrence networks from publicly available 16S rRNA gene sequencing data of four extreme aquatic habitats. For each environment, we constructed networks including and excluding unknown organisms at multiple taxonomic levels and used network centrality measures to quantitatively compare networks. When the Unknown taxa were excluded from the networks, a significant reduction in degree and betweenness was observed for all environments. Strikingly, Unknown taxa occurred as top hubs in all environments, suggesting that “microbial dark matter” play necessary ecological roles within their respective communities. In addition, novel adaptation-related genes were detected after using 16S rRNA gene sequences from top-scoring hub taxa as probes to blast metagenome databases. This work demonstrates the broad applicability of network metrics to identify and prioritize key Unknown taxa and improve understanding of ecosystem structure across diverse habitats.
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Hajibaba, Majid, Mohsen Sharifi, and Saeid Gorgin. "The Influence of Memory-Aware Computation on Distributed BLAST." Current Bioinformatics 14, no. 2 (January 7, 2019): 157–63. http://dx.doi.org/10.2174/1574893613666180601080811.
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Background: One of the pivotal challenges in nowadays genomic research domain is the fast processing of voluminous data such as the ones engendered by high-throughput Next-Generation Sequencing technologies. On the other hand, BLAST (Basic Local Alignment Search Tool), a longestablished and renowned tool in Bioinformatics, has shown to be incredibly slow in this regard. Objective: To improve the performance of BLAST in the processing of voluminous data, we have applied a novel memory-aware technique to BLAST for faster parallel processing of voluminous data. Method: We have used a master-worker model for the processing of voluminous data alongside a memory-aware technique in which the master partitions the whole data in equal chunks, one chunk for each worker, and consequently each worker further splits and formats its allocated data chunk according to the size of its memory. Each worker searches every split data one-by-one through a list of queries. Results: We have chosen a list of queries with different lengths to run insensitive searches in a huge database called UniProtKB/TrEMBL. Our experiments show 20 percent improvement in performance when workers used our proposed memory-aware technique compared to when they were not memory aware. Comparatively, experiments show even higher performance improvement, approximately 50 percent, when we applied our memory-aware technique to mpiBLAST. Conclusion: We have shown that memory-awareness in formatting bulky database, when running BLAST, can improve performance significantly, while preventing unexpected crashes in low-memory environments. Even though distributed computing attempts to mitigate search time by partitioning and distributing database portions, our memory-aware technique alleviates negative effects of page-faults on performance.
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Galliano, Frédéric. "Dust Evolution from Nearby Galaxies: Bridging the Gap Between Local Universe and Primordial Systems." Proceedings of the International Astronomical Union 4, S255 (June 2008): 246–53. http://dx.doi.org/10.1017/s1743921308024897.
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AbstractThis paper presents the results of a study aimed at understanding the evolution of the dust properties, as a function of both the environmental conditions and the metal enrichment of the system. I first review the peculiar dust properties of dwarf galaxies, and discuss attempts to understand their origin. Then, I discuss the evolution of the PAH and dust abundances, constrained by the UV-to-radio SED of nearby galaxies, comparing the properties of low-metallicity environments and more evolved systems. I discuss the long term evolution of dust in galaxies, comparing the grain production by various stellar progenitors to their destruction by SN blast waves and in H ii regions. Finally, I will show how these models explain the paucity of PAHs in low-metallicity environments.
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Roy, Chandan, Philomin Juliana, Muhammad R. Kabir, Krishna K. Roy, Navin C. Gahtyari, Felix Marza, Xinyao He, et al. "New Genotypes and Genomic Regions for Resistance to Wheat Blast in South Asian Germplasm." Plants 10, no. 12 (December 8, 2021): 2693. http://dx.doi.org/10.3390/plants10122693.
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Wheat blast (WB) disease, since its first identification in Bangladesh in 2016, is now an established serious threat to wheat production in South Asia. There is a need for sound knowledge about resistance sources and associated genomic regions to assist breeding programs. Hence, a panel of genotypes from India and Bangladesh was evaluated for wheat blast resistance and a genome-wide association study (GWAS) was performed. Disease evaluation was done during five crop seasons—at precision phenotyping platform (PPPs) for wheat blast disease at Jashore (2018–19), Quirusillas (2018–19 and 2019–20) and Okinawa (2019 and 2020). Single nucleotide polymorphisms (SNP) across the genome were obtained using DArTseq genotyping-by-sequencing platform, and in total 5713 filtered markers were used. GWAS revealed 40 significant markers associated with WB resistance, of which 33 (82.5%) were in the 2NS/2AS chromosome segment and one each on seven chromosomes (3B, 3D, 4A, 5A, 5D, 6A and 6B). The 2NS markers contributed significantly in most of the environments, explaining an average of 33.4% of the phenotypic variation. Overall, 22.4% of the germplasm carried 2NS/2AS segment. So far, 2NS translocation is the only effective WB resistance source being used in the breeding programs of South Asia. Nevertheless, the identification of non-2NS/2AS genomic regions for WB resistance provides a hope to broaden and diversify resistance for this disease in years to come.
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Kou, Yanjun, Jiehua Qiu, and Zeng Tao. "Every Coin Has Two Sides: Reactive Oxygen Species during Rice–Magnaporthe oryzae Interaction." International Journal of Molecular Sciences 20, no. 5 (March 8, 2019): 1191. http://dx.doi.org/10.3390/ijms20051191.
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Reactive oxygen species (ROS) are involved in many important processes, including the growth, development, and responses to the environments, in rice (Oryza sativa) and Magnaporthe oryzae. Although ROS are known to be critical components in rice–M. oryzae interactions, their regulations and pathways have not yet been completely revealed. Recent studies have provided fascinating insights into the intricate physiological redox balance in rice–M. oryzae interactions. In M. oryzae, ROS accumulation is required for the appressorium formation and penetration. However, once inside the rice cells, M. oryzae must scavenge the host-derived ROS to spread invasive hyphae. On the other side, ROS play key roles in rice against M. oryzae. It has been known that, upon perception of M. oryzae, rice plants modulate their activities of ROS generating and scavenging enzymes, mainly on NADPH oxidase OsRbohB, by different signaling pathways to accumulate ROS against rice blast. By contrast, the M. oryzae virulent strains are capable of suppressing ROS accumulation and attenuating rice blast resistance by the secretion of effectors, such as AvrPii and AvrPiz-t. These results suggest that ROS generation and scavenging of ROS are tightly controlled by different pathways in both M. oryzae and rice during rice blast. In this review, the most recent advances in the understanding of the regulatory mechanisms of ROS accumulation and signaling during rice–M. oryzae interaction are summarized.
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Coppola, Luigi, Denny Coffetti, Elena Crotti, Gabriele Gazzaniga, and Tommaso Pastore. "The Durability of One-Part Alkali-Activated Slag-Based Mortars in Different Environments." Sustainability 12, no. 9 (April 27, 2020): 3561. http://dx.doi.org/10.3390/su12093561.
Full textAbstract:
The paper assesses the durability of one-part alkali-activated slag-based mortars (AAS) in different aggressive environments, such as calcium chloride- and magnesium sulphate-rich solutions, in comparison with traditional cementitious mortars at equal water to binder ratio. Moreover, the freezing and thawing resistance was evaluated on mortars manufactured with and without air entraining admixture (AEA). Experimental results indicate that the alkali content is a key parameter for durability of AAS: the higher the alkali content, the higher the resistance in severe conditions. In particular, high-alkali content AAS mortars are characterized by freeze–thaw resistances similar to that of blast furnace cement-based mixtures, but lower than that of Portland cement-mortars while AAS with low activators dosages evidence a very limited resistance in cold environment. The effectiveness of AEA in enhancement of freeze–thaw resistance is confirmed also for AAS mortars. Moreover, AAS mixtures are quasi-immune to expansive calcium oxychloride formation in presence of CaCl2-based deicing salts, but they are very vulnerable to magnesium sulphate attack due to decalcification of C-S-H gel and gypsum formation.
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Dompieri, Maurício, Jacopo Seccatore, Giorgio de Tomi, Beck Nader, José Renato B. de Lima, and Arthur P. Chaves. "An Innovative Approach to Mine Blast Fragmentation Management Using Complexity Analysis: Three Case Studies." Materials Science Forum 805 (September 2014): 454–59. http://dx.doi.org/10.4028/www.scientific.net/msf.805.454.
Full textAbstract:
This paper introduces an innovative solution for devising a robust blasting plan that will present consistently good fragmentation performance under highly uncertain environments. The analysis will be carried out using complexity analysis tools, a model-free approach to complex systems which is particularly well suited to the problem of finding non-deterministic dependencies between multiple variables. The study is backed-up by data from over 2,000 blast records from Brazilian mines and identifies what are the critical aspects of the system and how to manage the blasting plan to reduce their impact on its performance.
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Caçoilo, A., R. Mourão, B. Belkassem, F. Teixeira-Dias, J. Vantomme, and D. Lecompte. "Blast Wave Assessment in a Compound Survival Container: Small-Scale Testing." Proceedings 2, no. 8 (July 23, 2018): 540. http://dx.doi.org/10.3390/icem18-05459.
Full textAbstract:
Propagation of shock waves in partially- or fully-confined environments is a complex phenomenon due to the possibility of multiple reflections, diffractions and superposition of waves. In a military context, the study of such phenomena is of extreme relevance to the evaluation of protection systems, such as survival containers, for personnel and equipment. True scale testing of such structures is costly and time consuming but small-scale models in combination with the Hopkinson-Cranz scaling laws are a viable alternative. This paper combines the use of a small-scale model of a compound survival container with finite element analysis (with LS-DYNA) to develop and validate a numerical model of the blast wave propagation. The first part of the study details the experimental set-up, consisting of a small-scale model of a survival container, which is loaded by the detonation of a scaled explosive charge. The pressure-time histories are recorded in several locations of the model. The second part of the study presents the numerical results and a comparison with the experimental data.