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PubMed1984

Ocular injuries from carbonated soft drink bottle explosions.

Sixteen cases of ocular injuries serious enough to require admission to Ibn-Sina Hospital, Kuwait, Arabian Gulf, due to explosion of glass bottles of carbonated soft drinks are reported over a period of 14 months from the beginning of July 1981 to the end of August 1982. Prevalence was much greater in the summer months and among children. Explosions of bottles without prior agitation occurred in 11 cases (68.7%). High environmental temperature and defective bottles were the most important predisposing factors. Preventive measures we suggest are better standards for manufacturers, more careful inspection of returnable bottles to detect defective ones, a separate detailed warning label on all bottles, and health education especially of school children about this and other risks of serious injury to the eyes and other parts of the body.

Adult↗
PubMed2006

Changes in exercise characteristics, maximal voluntary contraction, and explosive strength during prolonged tennis playing.

OBJECTIVES: To examine changes in exercise characteristics, maximal voluntary contraction, and explosive strength during prolonged tennis playing. METHODS: Maximal isometric voluntary contraction (MVC), leg stiffness (hopping), and peak power in squat (SJ) and countermovement (CMJ) jumps were measured before, every 30 minutes during, and 30 minutes after a three hour tennis match in 12 well trained players. Heart rate (HR), the effective playing time (EPT), rating of perceived exertion (RPE), and muscle soreness of knee extensors were also measured. RESULTS: Decreases in MVC (-9%; p < 0.05) and leg stiffness (-9%; p = 0.17) were observed after the match and were significantly correlated (r = 0.66; p = 0.05). Peak power in SJ and CMJ tests was maintained during the match but was lower (p < 0.001) 30 minutes after. Average HR and EPT were 144 (8) beats/min and 21 (4)% respectively. A strong correlation was found between EPT and HR (r = 0.93; p < 0.05). RPE and muscle soreness increased linearly during the exercise and were significantly correlated (r = 0.99; p < 0.001). CONCLUSIONS: Progressive reductions in maximal voluntary strength and leg stiffness highly correlated with increases in perceived exertion and muscle soreness were observed throughout a three hour tennis match, whereas explosive strength was maintained and decreased only after the match. These alterations may result in less efficient on-court movement and stroke production. They are, however, lower than those reported during continuous exercise of the same duration. The intermittent pattern of tennis and the numerous stretch-shortening cycle movements partly explain these results.

Adult↗
PubMed1991

Bilateral anterior cerebral artery infarction resulting from explosion-type injury to the head and neck.

A 43-year-old woman suffered a blast-type injury to the head and neck. She subsequently developed bilateral internal carotid artery occlusion and bilateral anterior cerebral artery infarction not demonstrated by magnetic resonance imaging scan 24 hours after the explosion, but confirmed by a second scan 8 days after the explosion. In patients with blast-type injury to the head and neck who develop coma with a nonfocal neurological exam, the possibility of bilateral carotid artery occlusion and bilateral ischemic infarction should be considered.

Accidents, Home↗
PubMed1983

Problems in the diagnosis of intermittent explosive disorder.

The authors studied the accuracy with which intermittent explosive disorder was diagnosed in a university hospital setting. An index of diagnostic features abstracted from the description of intermittent explosive disorder in DSM-III was used for chart review. Diagnosis of the disorder was made in 20 out of 830 admissions (2.4%). In 14 cases (1.7%) it was a primary one; in another five (.6%) it was secondary; and in one case (.1%) it was tertiary. The authors discuss the varied rigorousness of the diagnosis and the importance of using an index of diagnostic features to enhance diagnostic accuracy.

Adolescent↗
PubMed1997

Inactivation of food microorganisms by high-pressure carbon dioxide treatment with or without explosive decompression.

In order to elucidate the sterilization mechanism underlying the explosive decompression system, baker's yeast was pressurized with CO2, N2O, N2, or Ar gas at 40 atm and 40 degrees C for 4h, and then explosively discharged. The survival ratio was markedly decreased only by the treatments with CO2 and N2O, which are relatively soluble gases in water, suggesting that the microorganisms' death may be highly correlated with gas absorption by the cells. Lower decompression rates to atmospheric pressure, however, led to neither any lower reduction of remaining cells nor any smaller release of total cellular proteins. Furthermore, operating with a longer treatment time and smaller number of repetitions was usually more lethal than with a shorter time and more frequent repetition. From these results, most of the yeast cells appear to have been sterilized during the pressurization process. The spore cells of B. megaterium are considered to have been killed in a somewhat different manner, because of their distinct sensitivity to the applied gases.

Argon↗
PubMed2005

Trace detection of explosives with low vapor emissions by laser surface photofragmentation-fragment detection spectroscopy with an improved ionization probe.

Trace explosive residues are measured in real time by surface laser photofragmentation-fragment detection (SPF-FD) spectroscopy at ambient conditions. A 248-nm laser photofragments the target residue on a substrate, and a 226-nm laser ionizes the resulting NO fragment by resonance-enhanced multiphoton ionization by means of its A-X (0, 0) transitions near 226 nm. We tested two probes on selected explosives and modeled their electric field in the presence of a substrate with an ion optics simulation program. The limits of detection range from 1 to 15 ng/cm2 (signal-to-noise ratio of 3) at 1 atm and 298 K and depend on the electrode orientation and mechanism for NO formation.

Journal Article↗
PubMed2006

Fluorescence of aromatic amines and their fluorescamine derivatives for detection of explosive vapors.

Nitroaromatics (such as dinitrotoluene, trinitrotoluene, and nitrobenzene) found in explosive vapors from buried landmines can be reduced to aminoaromatics by a novel process involving Pd metal nanocatalysts prepared in supercritical fluid carbon dioxide and supported on multi-walled carbon nanotubes. These aminoaromatics are fluorescent and, if desired, the fluorescence yield can be increased and the fluorescence maxima shifted further toward the red by reaction with appropriate derivatizing agents such as fluorescamine. Corrected spectra for these chemicals and their derivatives are included. Subpicomolar detection limits have already been achieved using a laboratory spectrofluorometer with a 150 W Xe arc lamp. Using lasers as excitation sources, this approach has the potential for developing a field sensor competitive with other methods currently used for detecting explosive vapors from land mines.

Journal Article↗
PubMed2006

Ethanol production from steam-explosion pretreated wheat straw.

Bioconversion of cereal straw to bioethanol is becoming an attractive alternative to conventional fuel ethanol production from grains. In this work, the best operational conditions for steam-explosion pretreatment of wheat straw for ethanol production by a simultaneous saccharification and fermentation process were studied, using diluted acid [H2SO4 0.9% (w/w)] and water as preimpregnation agents. Acid- or water-impregnated biomass was steam-exploded at different temperatures (160-200 degrees C) and residence times (5, 10, and 20 min). Composition of solid and filtrate obtained after pretreatment, enzymatic digestibility and ethanol production of pretreated wheat straw at different experimental conditions was analyzed. The best pretreatment conditions to obtain high conversion yield to ethanol (approx 80% of theoretical) of cellulose-rich residue after steam-explosion were 190 degrees C and 10 min or 200 degrees C and 5 min, in acid-impregnated straw. However, 180 degrees C for 10 min in acid-impregnated biomass provided the highest ethanol yield referred to raw material (140 L/t wheat straw), and sugars recovery yield in the filtrate (300 g/kg wheat straw).

Bioreactors↗
PubMed2003

Effect of explosive resistance training on titin and myosin heavy chain isoforms in trained subjects.

The purpose of this investigation was to evaluate changes in myosin heavy chain (MyHC) and titin isoforms after using various loads during explosive jump squat training. Twenty-four male athletic subjects were recruited for this study. Two experimental groups performed 8-weeks of jump squats using either 30% (n = 9) or 80% (n = 9) of their previously determined 1 repetition maximum. A third group served as controls (n = 6). Muscle biopsies were obtained before and after 8 weeks from vastus lateralis. The analysis of titin within these subjects confirmed that human skeletal muscle contains 2 isoforms of titin. There was no significant group x time interaction for MyHC or titin isoform expression. The data from this investigation indicates that a relatively short period of explosive resistance training results in negligible changes in the expression of MyHC or titin isoforms.

Adult↗
PubMed2004

Enhancing the attenuation of explosives in surface soils at military facilities: sorption-desorption isotherms.

The primary objective of the present study was to develop inexpensive soil amendments that can be applied to enhance the adsorption of energetic compounds on military training ranges, thus limiting the potential for these compounds to migrate to groundwater. Adsorption and desorption isotherms were determined for 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine with a wide variety of natural and man-made adsorbents, including wheat straw, sawdust, peat moss, ground rubber tires, and clays. Among the various adsorbents tested, peat moss proved to be the most effective sorbent for the three explosives. The adsorption coefficients (Kd(s)) for TNT and RDX with peat (310 and 87 L/kg, respectively) were at least two orders of magnitude higher than that determined for adsorption of these energetics with two surface soils. The adsorption-desorption isotherms for the explosives showed considerable hysteresis (Kd(s) < Kd(d)) with some of the solid adsorbents, suggesting that the sorption process is not readily reversible but, rather, that some fraction of the adsorbed contaminant is either irreversibly bound or present as a slowly desorbed fraction. The data indicate that the application of specific adsorbents to soils at military impact ranges may significantly improve the protection of local groundwater resources.

Adsorption↗
PubMed2004

Acute and chronic toxicity of the new explosive CL-20 to the earthworm (Eisenia andrei) exposed to amended natural soils.

Monocyclic nitramine explosives such as 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) are toxic to a number of ecological receptors, including earthworms. The polycyclic nitramine CL-20 (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane) is a powerful explosive that may replace RDX and HMX, but its toxicity is not known. In the present study, the lethal and sublethal toxicities of CL-20 to the earthworm (Eisenia andrei) are evaluated. Two natural soils, a natural sandy forest soil (designated RacFor2002) taken in the Montreal area (QC, Canada; 20% organic carbon, pH 7.2) and a Sassafras sandy loam soil (SSL) taken on the property of U.S. Army Aberdeen Proving Ground (Edgewood, MD, USA; 0.33% organic carbon, pH 5.1), were used. Results showed that CL-20 was not lethal at concentrations of 125 mg/kg or less in the RacFor2002 soil but was lethal at concentrations of 90.7 mg/kg or greater in the SSL soil. Effects on the reproduction parameters such as a decrease in the number of juveniles after 56 d of exposure were observed at the initial CL-20 concentration of 1.6 mg/kg or greater in the RacFor2002 soil, compared to 0.2 mg/kg or greater in the SSL soil. Moreover, low concentrations of CL-20 in SSL soil (approximately 0.1 mg/kg; nominal concentration) were found to reduce the fertility of earthworms. Taken together, the present results show that CL-20 is a reproductive toxicant to the earthworm, with lethal effects at higher concentrations. Its toxicity can be decreased in soils favoring CL-20 adsorption (high organic carbon content).

Adsorption↗
PubMed2005

Dietary exposure of fathead minnows to the explosives TNT and RDX and to the pesticide DDT using contaminated invertebrates.

Explosive compounds have been released into the environment during manufacturing, handling, and usage procedures. These compounds have been found to persist in the environment and potentially promote detrimental biological effects. The lack of research on bioaccumulation and bioconcentration and especially dietary transfer on aquatic life has resulted in challenges in assessing ecological risks. The objective of this study was to investigate the potential trophic transfer of the explosive compounds 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) using a realistic freshwater prey/predator model and using dichlorodiphenyltrichloroethane (DDT), a highly bioaccumulative compound, to establish relative dietary uptake potential. The oligochaete worm Lumbriculus variegatus was exposed to 14C-labeled TNT, RDX or DDT for 5 hours in water, frozen in meal-size packages and subsequently fed to individual juvenile fathead minnows (Pimephales promelas). Fish were sampled for body residue determination on days 1, 2, 3, 4, 7, and 14 following an 8-hour gut purging period. Extensive metabolism of the parent compound in worms occurred for TNT but not for RDX and DDT. Fish body residue remained relatively unchanged over time for TNT and RDX, but did not approach steady-state concentration for DDT during the exposure period. The bioaccumulation factor (concentration in fish relative to concentration in worms) was 0.018, 0.010, and 0.422 g/g for TNT, RDX and DDT, respectively, confirming the expected relatively low bioaccumulative potential for TNT and RDX through the dietary route. The experimental design was deemed successful in determining the potential for trophic transfer of organic contaminants via a realistic predator/prey exposure scenario.

Animals↗
PubMed1998

Experimental study on mechanism and protection of stress ulcer produced by explosive noise.

AIM:To establish an experimental model of stress ulcer produced by explosive noise, and to probe into its mechanism and protection.METHODS:The country standard Wistar white rats were randomly divided into control group(n =8), which were neither stimulated nor protected, and stimulating group (divided into subgroups A, B and C, including 8 rats each which were decapitated to draw blood for test immediately, 12 hours and 24 hours after stimulation) and prevention group (divided into subgroups A, B and C, having 8 rats each, subgroup A was given cimetidine, B anisodamine and C both drugs). Firing noises of submachine guns were used as inflicting factor. The rats were fasted for 24 hours and stimulated by firing noise for 12 hours. The change of ulcer index, gastric mucosal and related serum hormones were observed.RESULTS:Stress ulcer was significant in the stimulating group, and its ulcer index (8.6 ± 0.6) was remarkably higher than that in both the control group and prevention group (0.3 ± 0.1, P < 0.01).Its serum gastrin (Gas ng/L, 294 ± 163 vs 63 ± 40,P< 0.01) and endothelin (ET ng/L, 181 ± 57 vs 135 ± 42, P < 0.1) were apparently higher than those in the control group, and its serum nitric oxide (NO) level was conspicuously lower than that in the control group (ng/L, 0.3 ± 0.1 vs 0.8 ± 0.5 P <0.5), while the serum gastrin level (ng/L, 556 ± 225) in prevention group was distinctly higher than that in both the control (P<0.1) and stimulating group (P < 0.5). There were no significant differences in the changes of ET and NO between the control and the stimulating groups.CONCLUSION:Stress ulcer model of rats can be successfully established by the stimulation of explosive noise. Gas, ET and NO are related to the formation of stress ulcer, and play an important role in its mechanism. Hepatic function affected by noise is observed in this experiment.

Journal Article↗
PubMed2001

The use of capillary electrophoresis in the detection of monomethylamine and benzoate ions in the forensic examination of explosives residues.

Capillary electrophoresis (CE) is used in the ATF Forensic Science Laboratories for the analysis of inorganic ions commonly encountered in post-blast residues including monomethylamine (MMA) and benzoate ions. Monomethylamine nitrate is found in Tovex, a water gel explosive. Sodium benzoate is added to Pyrodex, as a fuel and burn rate modifier. In the analysis of explosive residues, these ions are used as an indicator for the presence of Tovex and Pyrodex. Traditionally, these two ions, along with other ions of interest were analyzed by spot tests and ion chromatograph (IC). CE is currently being used in place of spot tests as a confirmation technique for IC.

Journal Article↗
PubMed2001

The load that maximizes the average mechanical power output during explosive bench press throws in highly trained athletes.

The power output generated with different barbell loads and which resistance generated the maximum mechanical power output (Pmax) during explosive bench press-type throws (BT) in a smith machine device were investigated in power-trained athletes. Thirty-one rugby league players were tested for 1 repetition maximum (1RM) free-weight bench press strength (1RM BP). Maximal power output was assessed by the Plyometric Power System during BT using resistances of 40, 50, 60, 70, and 80 kg (BT P40, BT P50, BT P60, BT P70, and BT P80). It was found that BT Pmax occurred with resistance of 70.1 +/- 7.9 kg, representing 55 +/- 5.3% of 1RM BP of 129.7 +/- 14.3 kg. The power output with all loads except the BT P70 were different from the BT Pmax. The BT P70 and BT P80 were not different from each other. Furthermore, the BT P60 and BT P80 were not different from each other. This suggests that although resistances of 55% 1RM BP may maximize power output during explosive BT, loads in the range of 46-62% also allow for high power outputs. Resistances of 31-45% of 1RM BP resulted in significantly lower power outputs. Compared with previous research of BT in strength-trained athletes, the results of this investigation suggest that power-trained athletes may generate their Pmax at higher percentages of 1RM.

Adult↗
PubMed2001

Validity and reliability of a medicine ball explosive power test.

The purpose of this study was to evaluate the validity and reliability of a medicine ball throw test to assess explosive power. Twenty competitive sand volleyball players (10 male players, 10 female players) performed a medicine ball throw and a standard countermovement vertical jump. The subjects attended 2 sessions; at each session, 3 attempts of each test were completed. The movement pattern for the medicine ball throw was a backward overhead toss. To standardize for body weight, a power index was calculated for the countermovement vertical jump using the Lewis formula. Validity was assessed using the best score for both the throw and the jump, and reliability was assessed using the best score from each session. There was a strong correlation between the distance of the medicine ball throw and the power index for the countermovement vertical jump (r = 0.906, p < 0.01). For the countermovement vertical jump, the test-retest reliability was 0.993 (p < 0.01), and for the medicine ball throw, the test-retest reliability was 0.996 (p < 0.01). These findings suggest that the medicine ball throw test is a valid and reliable test for assessing explosive power for an analogous total-body movement pattern and general athletic ability.

Adolescent↗
PubMed1975

Telemetered renal responses in dogs during detection of explosives.

The primary objectove of this work was to develop and test a method of measuring and characterizing renal hemodynamic responses in unrestrained dogs. Recordings of left kidney blood flow and abdominal aortic pressure were obtained from unrestrained dogs through the use of a two-channel implanted telemetry system during episodes of search and detection of simulated explosives. In each of a number of sequences, the dog was first given a start signal, and after locating the hidden device, was rewarded with food. Data were assessed at the start, find, and recovery segments. The dynamic flow and pressure, together with a hydraulic renal model, were used to derive the total preglomerular and postglomerular vascular resistances and the mean level of glomerular hydrostatic pressure. Data from three dogs obtained by telemetry and analyzed through the use of the model have shown that compared to the start of the test, the location of hidden explosives results in a decrease in both the level of mean aortic blood pressure and the preglomerular resistance; whereas, the reward results in an elevation of mean blood pressure and preglomerular resistance. The postglomerular resistance varied less than the preglomerular resistance, and mean flow did not vary significantly. This work has shown that the stimulation of a reward and the successful performance of a task lead to significant renal responses in dogs. It has further shown that telemetry, when employed with improved data analysis techniques, permits renal hemodynamics to be assessed in unrestrained animal subjects.

Animals↗
PubMed2001

[Prediction of retention parameters of explosives by artificial neural network].

The quantitative relationship between the retention parameters and the structure of explosives is discussed. Molecular topological indices are used to represent the structure. Based on the back-propagation algorithm, a quantitative model was established after a training process of a train-set containing 20 explosives being completed. The Sigmoid function was chosen as the transmit function. The retention parameters (log kappa w and S) acted as output vectors, while molecular connecting indices (0 chi, 1 chi, 2 chi) and edge adjacent indices(epsilon) acted as input vectors. The input vectors were normalized in the range of -3-3 and the output vectors were normalized in the range of 0-1. The accuracy of network was 0.5 and the beginning value of studying pace (eta) was 0.2, the momentum factor (alpha) was 0.5. The results showed that the yield model reflected the relationship between the structure and retention index of compounds, and had high accuracy. Most of the relative errors were below +/- 5%.

English Abstract↗