Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “EXPLOSIONS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 775 records · Page 43Linked to original sources
PubMed2004

Biodegradation of the nitramine explosives hexahydro-1,3,5-trinitro-1,3,5-triazine and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine in cold marine sediment under anaerobic and oligotrophic conditions.

The in situ degradation of the two nitramine explosives, hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), was evaluated using a mixture of RDX and HMX, incubated anaerobically at 10 degrees C with marine sediment from a previous military dumping site of unexploded ordnance (UXO) in Halifax Harbor, Nova Scotia, Canada. The RDX concentration (14.7 mg.L-1) in the aqueous phase was reduced by half in 4 days, while reduction of HMX concentration (1.2 mg.L-1) by half required 50 days. Supplementation with the carbon sources glucose, acetate, or citrate did not affect the removal rate of RDX but improved removal of HMX. Optimal mineralization of RDX and HMX was obtained in the presence of glucose. Using universally labeled (UL)-[14C]RDX, we obtained a carbon mass balance distributed as follows: CO2, 48%-58%; water soluble products, 27%-31%; acetonitrile extractable products, 2.0%-3.4%; and products covalently bound to the sediments and biomass, 8.9% (in the presence of glucose). The disappearance of RDX was accompanied by the formation of the mononitroso derivative hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX) and formaldehyde (HCHO) that subsequently disappeared. In the case of HMX, mineralization reached only 13%-27% after 115 days of incubation in the presence or absence of the carbon sources. The disappearance of HMX was also accompanied by the formation of the mononitroso derivative. The total population of psychrotrophic anaerobes that grew at 10 degrees C was 2.6 x 10(3) colony-forming units.(g sediment dry mass)-1, and some psychrotrophic sediment isolates were capable of degrading RDX under conditions similar to those used for sediments. Based on the distribution of products, we suggest that the sediment microorganisms degrade RDX and HMX via an initial reduction to the corresponding mononitroso derivative, followed by denitration and ring cleavage.

Acetates↗
PubMed1994

A control strategy for the execution of explosive movements from varying starting positions.

1. Humans can execute explosive movements such as jumping and hitting an object irrespective of the starting position from which these movements have to be initiated; in fact, variability of kinematic parameters has been shown to decrease in the course of the movement. 2. We address the question of whether it is necessary to adapt the stimulation pattern of the muscles to such variations in starting position or whether the stabilizing effect of intrinsic muscle properties is such that one single muscle stimulation pattern might be used for a wide range of starting positions. 3. Specifically, we address this question for maximum-height human vertical squat jumping, using an approach based on mathematical modeling and computer simulation. The stimulation pattern of the muscles is the input of the model and the resulting movement is the output. 4. The optimal stimulation pattern for a starting position in the middle of the range of starting positions considered does not lead to adequate performance for other starting positions in that range. 5. However, a muscle stimulation pattern can be found that does result in close to optimal achievement for a wide range of starting positions. This muscle stimulation pattern, which is not optimal for any specific starting position, may be considered as "control that works" as opposed to "optimal control." 6. The latter muscle stimulation pattern also leads to adequate behavior for "new" starting positions both within and outside the range considered.

Adult↗
PubMed1980

Calibration of time derivatives of forced vital capacity by explosive decompression.

A simple, portable, inexpensive device is described that simulates expiratory flow curves for calibration of spirometers. A 4-L metal cylinder filled with copper mesh is fitted with a precision manometer. The pressure is increased to twice atmospheric and released by explosive decompression through 4 easily interchangeable resistors. The ratio of forced expiratory volume in one second to forced vital capacity ranged from 0.80 to 0.25, thus encompassing the range from normal to severe obstruction. Accuracy was defined by 25 measurements of forced vital capacity that differed by no more than 0.5% from the actual cylinder volume. Repeatability was reflected by a standard deviation of at most 0.04 L/s for one-second forced expiratory volume, mid-expiratory flow, and instantaneous flows at 50 and 25% of the forced vital capacity. Peak flow was less reproducible. Calibrations of a water spirometer at increased altitude and at temperatures from 4 degrees to 37 degrees C revealed no significant changes in volume or flow rates. Standard values have remained unchanged for 2.5 yr. Three volume spirometers and 2 primary flow devices were tested extensively.

Altitude↗
PubMed1983

Long-term effects of exposure to sulfur dioxide. Lung function four years after a pyrite dust explosion.

The lung function of 7 men accidentally exposed to sulfur dioxide (SO2) in a pyrite dust explosion was followed for 4 yr. The greatest decrease in forced vital capacity, forced expiratory volume in one second, and maximal midexpiratory flow was observed 1 wk after the accident. After about 3 months no further decrement occurred. The pattern of spirometric findings was obstructive in 6 and restrictive in 1 of the patients. Four years after the accident a reversible obstruction of the bronchi was still observable in 3. Four patients reacted positively to the histamine challenge test. Two patients either did not respond to bronchodilator or did not react to histamine. The results suggest that bronchial hyperreactivity is a frequent sequela after exposure to high concentrations of SO2. The hyperreactivity may persist for several years.

Accidents, Occupational↗
PubMed1985

Metoprolol for intermittent explosive disorder.

Metoprolol, a selective beta 1-adrenoreceptor blocker, was administered to two patients with intermittent explosive disorder who had not done well with previous medications, including propranolol and carbamazepine. Both patients improved dramatically, suggesting clinical and theoretical relevance.

Adult↗
PubMed1992

Hypothalamic lesions and intermittent explosive disorder.

The authors present two cases of patients with craniopharyngiomas who meet the DSM-III-R criteria for intermittent explosive disorder. Episodes of rage developed before and/or after surgery for removal of the craniopharyngioma. Magnetic resonance imaging revealed hypothalamic-hypophyseal involvement. It is suggested that hypothalamic lesions played a major role in the development of aggressive behavior in both cases.

Adult↗
PubMed1989

Effects of different intensities of fatigue on performing a sport skill requiring explosive muscular effort: a test of the specificity of practice principle.

The purpose of this study was to ascertain the effects of high, moderate, and low physical fatigue on performing the shot put, a sport skill that requires explosive muscular effort. 44 subjects practiced the shot put until mastery was achieved. They then experienced one of four fatigue intensities during a 20-trial practice period (no fatigue, 45, 60 or 75% of their predicted maximum oxygen uptake) to induce light, moderate, or heavy fatigue, respectively, after which subjects then engaged in criterion performance for 5 trials under each of the fatigue intensities, with one week in between. Distance thrown and expert assessment of performance technique were dependent variables. Analysis indicated that criterion performance was optimal for both distance and form after subjects experienced light fatigue during practice and criterion performance. The specificity of practice hypothesis was partially supported for the light fatigue condition, but not for the other intensities.

Adolescent↗
PubMed1989

Cardiac dysrhythmia with the use of clonidine in explosive disorder.

Clonidine has been used in the management of hypertension in adults with few cases of cardiac dysrhythmia reported. These appear to occur most frequently in association with preexisting cardiac disease or toxic concentrations of the drug. We observed a case of clonidine-induced bradycardia and irregular firing of the sinoatrial node in a child who does not have cardiac disease given low doses of the drug in the treatment of intermittent explosive disorder.

Arrhythmias, Cardiac↗
PubMed2004

Managing the health effects of the explosive remnants of war.

Many civilian deaths and injuries across the globe are a consequence of 'explosive remnants of war' (ERW). These ERW include mines, unexploded ordnance (UXO) and cluster bombs. The numbers of deaths, injuries and resulting disabilities from ERW are expected to increase as armed conflicts proliferate. This will have a substantial effect on all aspects of health. This article first describes the mechanisms of these ERW and the nature of the injuries they can cause. It then briefly outlines the immediate medical management such injuries require; the long-term outcomes and sequelae, and what can be done to manage them. It highlights how research and medical interventions must take into account cultural, social and economic factors in addition to utilising safe and appropriate techniques and practices. The article concludes by noting that medical personnel are well placed not only to intervene and manage the direct health effects of ERW, but also indirectly by advocating on behalf of those affected by adding their voices to campaigns against their proliferation.

Amputation, Surgical↗
PubMed2005

Out of Tanganyika: genesis, explosive speciation, key-innovations and phylogeography of the haplochromine cichlid fishes.

BACKGROUND: The adaptive radiations of cichlid fishes in East Africa are well known for their spectacular diversity and their astonishingly fast rates of speciation. About 80% of all 2,500 cichlid species in East Africa, and virtually all cichlid species from Lakes Victoria (approximately 500 species) and Malawi (approximately 1,000 species) are haplochromines. Here, we present the most extensive phylogenetic and phylogeographic analysis so far that includes about 100 species and is based on about 2,000 bp of the mitochondrial DNA. RESULTS: Our analyses revealed that all haplochromine lineages are ultimately derived from Lake Tanganyika endemics. We find that the three most ancestral lineages of the haplochromines sensu lato are relatively species poor, albeit widely distributed in Africa, whereas a fourth newly defined lineage - the 'modern haplochromines' - contains an unparalleled diversity that makes up more than 7% of the worlds' approximately 25,000 teleost species. The modern haplochromines' ancestor, most likely a riverine generalist, repeatedly gave rise to similar ecomorphs now found in several of the species flocks. Also, the Tanganyikan Tropheini are derived from that riverine ancestor suggesting that they successfully re-colonized Lake Tanganyika and speciated in parallel to an already established cichlid adaptive radiation. In contrast to most other known examples of adaptive radiations, these generalist ancestors were derived from highly diverse and specialized endemics from Lake Tanganyika. A reconstruction of life-history traits revealed that in an ancestral lineage leading to the modern haplochromines the characteristic egg-spots on anal fins of male individuals evolved. CONCLUSION: We conclude that Lake Tanganyika is the geographic and genetic cradle of all haplochromine lineages. In the ancestors of the replicate adaptive radiations of the 'modern haplochromines', behavioral (maternal mouthbrooding), morphological (egg-spots) and sexually selected (color polymorphism) key-innovations arose. These might be - together with the ecological opportunity that the habitat diversity of the large lakes provides - responsible for their evolutionary success and their propensity for explosive speciation.

Animals↗
PubMed2005

Unusual explosive growth of a squamous cell carcinoma of the scalp after electrical burn injury and subsequent coverage by sequential free flap vascular connection--a case report.

BACKGROUND: Squamous cell carcinomos may arise from chronic ulcerating wounds in scars, most commonly postburn scars. Tumour growth usually takes place over months to years. Localization on the scalp is a relatively rare condition. CASE PRESENTATION: This report presents the case of a 63-year-old man with chronic ulceration of a postburn scar of the scalp due to an electrical burn 58 years ago. Sudden tumour growth started within weeks and on presentation already had extended through the skull into frontal cortex. After radical tumour resection, defect was covered with a free radial forearm flap. Local recurrence occurred 6 weeks later. Subsequent wide excision including discard of the flap and preservation of the radial vessels was followed by transfer of a free latissimus dorsi muscle flap, using the radial vessels of the first flap as recipient vessels. The patient received radiotherapy post-operatively. There were no problems with flap survivals or wound healing. Due to rapidly growing recurrence the patient died 2 months later. CONCLUSION: Explosive SCC tumour growth might occur in post-burn scars after more than 50 years. As a treatment option the use of sequential free flap connections might serve in repeated extensive tumour resections, especially in the scalp region, where suitable donor vessels are often located in distance to the defect.

Burns, Electric↗
PubMed1988

Explosion of the orbital roof due to electrical current.

Prolonged contact with high voltage electricity can cause severe damage to the brain. Contact with the skull can produce heating of the brain and the cerebrospinal fluid, which may result in an explosion of the orbital roofs with downward displacement of the brain into both orbits.

Adult↗
PubMed1999

Radiological states around the Kraton-4 underground nuclear explosion site in Sakha.

A radiological survey around the site of Kraton-4, an underground nuclear explosion (Yield of 20 kt, depth of 560 m, 1978) in Sakha was carried out in March 1998. Gamma survey and in-situ spectroscopy on the ground exhibited quite normal levels: a dose rate of 0.022 microSv/h and Cs-137 surface contamination of less than 1.1 kBq/m2 around the hypocenter. The results suggested no remarkable leakage of radioactivity from the epicenter to the ground surface at least not for non-rare gas elements as of 1998.

Dose-Response Relationship, Radiation↗
PubMed2000

High incidence of micronuclei in lymphocytes from residents of the area near the Semipalatinsk nuclear explosion test site.

The Semipalatinsk area is highly contaminated with radioactive fallout from 40 years of continuous nuclear testing. The biological effects on human health in this area have not been studied. Significant remaining radioactivities include long-lived radioisotopes of 238,239,400Pu, 137Cs and 90Sr. To evaluate the long-term biological effects of the radioactive fallout, the incidence of micronuclei in lymphocytes from residents of the area was observed. Blood was obtained from 10 residents (5 females and 5 males, aged 47 to 55 years old) from each of the 3 areas of Znamenka, Dolon and Semipalatinsk, which are about 50-150 km from the nuclear explosion test site. For micronucleus assay, PHA-stimulated lymphocytes were cultured for 72 h and cytochalasin B was added at 44 h for detecting binuclear lymphocytes. Five thousand binuclear lymphocytes in each resident were scored. The means of micronucleus counts in 1,000 lymphocytes in residents of Semipalatinsk, Dolon and Znamenka were 16.3, 12.6, and 7.80, respectively, which were higher than those of the normal Japanese persons (4.66). These values were equivalent to the results obtained from 0.187-0.47 Gy of chronic exposure to gamma-rays at a dose rate of 0.02 cGy/min. The high incidence of micronuclei in residents of the Semipalatinsk nuclear test site area was mainly caused by internal exposure rather than external exposure received for the past 40 years.

Bone Marrow↗
PubMed2004

Time-resolved explosion dynamics of H2O droplets induced by femtosecond laser pulses.

Series of time-resolved still images of the explosion dynamics of micrometer-sized water droplets after femtosecond laser-pulse irradiation were obtained for different laser-pulse intensities. Amplified pulses centered around a wavelength of 805 nm with 1-mJ energy and 60-fs duration were focused onto the droplet to initiate the dynamics. Several effects, such as forward and backward plumes, jets, water films, and shock waves, were investigated. Additionally, the influence of different pulse durations produced by chirping the laser pulses was observed.

Journal Article↗
PubMed2006

Optical detection of honeybees by use of wing-beat modulation of scattered laser light for locating explosives and land mines.

An instrument is demonstrated that can be used for optical detection of honeybees in a cluttered environment. The instrument uses a continuous-wave diode laser with a center wavelength of 808 nm and an output power of 28 mW as the laser transmitter source. Light scattered from moving honeybee wings will produce an intensity-modulated signal at a characteristic wing-beat frequency (170-270 Hz) that can be used to detect the honeybees against a cluttered background. The optical detection of honeybees has application in the biological detection of land mines and explosives, as was recently demonstrated.

Animals↗
PubMed2004

Anti-Stokes Raman spectrometry with 1064-nm excitation: an effective instrumental approach for field detection of explosives.

Anti-Stokes Raman spectra of 28 explosive materials were obtained with 1064-nm excitation using fiber-optic sampling and a dispersive spectrograph equipped with a charge-coupled device (CCD) array detector. By using a silicon CCD detector, anti-Stokes features could clearly be observed for the majority of samples from -250 to -1650 cm(-1). Using the fiber-optic probe, spectra were routinely obtained from samples positioned up to twelve meters from the spectrograph within 240 s. The utility of an anti-Stokes correction routine is demonstrated, which routine allowed anti-Stokes spectra measured with 1064-nm excitation to be successfully searched and identified against libraries of Stokes spectra obtained using a Fourier transform (FT) Raman system equipped with a 1064-nm Nd:YAG laser.

Journal Article↗