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 253 records · Page 14Linked to original sources

A second survey of high explosives traces in public places.

This survey was carried out as a follow-up to a 1994 survey carried out by this laboratory (1) in order to determine the background levels of explosives traces in public places. The first survey concentrated on transport areas and police stations in and around London. This second study examines levels in four of the United Kingdom's major cities: Birmingham, Cardiff, Glasgow, and Manchester. Samples were taken at various transport sites and from hotels, private houses, private vehicles, and clothing. The survey showed that traces of the high explosives nitroglycerine (NG), trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN), and cyclotrimethylene trinitramine (RDX) are rare within the general public environment. Only one low-level trace of RDX was detected. NG, possibly associated with the use of firearms, was detected at low levels in two samples and 2,4-DNT was detected in a separate sample. No PETN was detected in any of the samples. The results of the survey indicate that it is unlikely that persons visiting public areas could become significantly contaminated with explosives. The analytical procedures employed would also have detected ethylene glycol dinitrate (EGDN) if present at levels greater than 2 ng, nitrobenzene (NB) if present at levels greater than 50 ng, mononitrotoluenes if present at levels greater than 50 ng, and the other common isomers of dinitrotoluene if these had been present at levels in excess of 10 ng. None of these were detected. The relatively high volatility of EGDN, NB, and the mononitrotoluenes would, however, cause traces of these compounds to disperse rapidly. A proportion of the samples (approximately 7%) were analyzed for the presence of HMX. No HMX was detected.

Dinitrobenzenes↗

White phosphorus poisoning--explosive encounter.

Poisoning by white or yellow phosphorus is reported in various forms and also in ages varying from infants to adults, but spontaneous combustion and explosion during its management has never been described. This incidence occurred while attempting to pass a Ryle's tube. Its free end first exhibited a yellow flame and this later on led to an explosive encounter. Role of static electricity generated while handling plastic materials leading to ignition and explosion cannot be overlooked.

Adolescent↗

[A study on relationship between rat brain tissues hurts of the gas explosion and the expression of protein kinase CamRNA and c-fos gene.].

OBJECTIVES: To explore relationship between rat brain tissues hurts of gas explosion and the expression of Protein Kinase C alpha mRNA. METHODS: Build up rat hurt model of gas explosion. In Situ Hybridization (IDH) technique was used to test Protein Kinase C alpha mRNA. Immunohistochemical Assays (IHA) was used to determine c-fos gene protein. RESULTS: Only a little a mount expression of PKC alpha mRNA and c-fos of the control group was detected. The expression of the cerebral cortex and hippocampus of PKC alpha mRNA 24 h, 48 h and the 48 h increased obviously, and the 48 h reached the peak of expression; (t = 4.12 P < 0.01). The expression of c-fos protein of the cerebral cortex and hippocampus started to increase obviously at 0.5 h and the 4 h reached the peak, then the strength lowered gradually and the expression level came back normal level on fifth day. CONCLUSION: The anoxia of brain tissues due to the gas explosion may promote the expression of PKCamRNA, and PKCamRNA could regulate the expression of the gene of c-fos. Both PKCamRNA and the gene of c-fos are involved in harmful processes to the nerve cells.

Animals↗

[A fatal accident due to harvester wheel explosion--a case report].

A fatal accident of a 48 year old woman due to harvester wheel explosion has been presented in this paper. A faulty technical condition of the wheel and the fact that it had been pumped to a pressure exceeding the permissible limit was the reason for the explosion. The woman sustained multiorgan injuries and microscopic examination revealed inter-alveolar septa rupture and intra-alveolar haemorrhage and oedema. The microscopic changes of the lungs prove that the shock wave was released during the wheel explosion.

Accidents, Occupational↗

[Characteristics of the acoustic analyzer trauma in blast trauma due to mine explosion].

Explosion barotraumas of the middle ear and neurosensory hypoacusis were observed in all examinees with ENT contusion. Acute neurosensory hypoacusis of any etiology is accompanied with stress which stimulates secretion of beta-endorphine showing adaptogenic, immunomodulating and anti-inflammatory properties. In patients with mine explosion trauma beta-endorphine was 2-2.5-fold higher than the basal concentration. Pharmacoacupuncture followed by electrostimulation of biologically active points improves acoustic function. Further target studies of current aspects of complex mine explosion trauma of the brain, acoustic and vestibular systems must be done.

Adolescent↗

[Intra vesical explosion during an endoscopic resection of a vesical tumor].

The intra vesical combustion of hydrogen and oxygen, form one mixture of explosive gas. Intra vesicale explosion during trans urethral resection is one rare incident. Its most dangerous manifestation during is vesical rupture. We demonstrate one case of intra vesical explosion during one endoscopic resection of one in the anterior face tumor of bladder. Damages on bladder are small. By going back to literature, we try to discuss the origin of intra vesical hydrogen and oxygen as well as the different preventive measures.

Carcinoma, Transitional Cell↗

[Cochlear microcirculation in living guinea pigs following explosion].

The cochlear microcirculation in living guinea pigs was observed, explosion was then imposed on the left ear and the velocity of blood cell flow and vessel diameters were measured within one hour. The results showed that: 1. there was an orderly stable movement of blood cells in all vascular beds under normal conditions; 2. the flow rate in both spiral ligament and stria vascularis increased promptly after explosion, that in the spiral ligament might return to normal within 30 minutes with vasodilatation, indicating increased blood supply early after explosion; 3. there was no relationship between changes in microcirculation and hearing loss and hair cell damage. The cause of hair cell damage and hearing loss were discussed and the techniques of vital microscopic studies of cochlear microcirculation assessed.

Animals↗

[Correlation of changes in compound action potential (CAP) tuning curves and cochlear lesion in guinea pigs after explosion].

The purpose of the present study was to investigate the sensitivity of compound action potential (CAP) tuning curves to changes of the cochlear status in guinea pigs after explosion and their ability to reflect specific histological variations. The results were as follows: 1. The CAP tuning curves were abnormally broad and the Q 10 dB values were reduced by a factor of 1 after explosion, indicating wider tuning. 2. The degree of broadening of the CAP tuning curves seemed to increase as the hair cell loss increased. 3. After explosion, the tip of the tuning curve shifted to frequencies significantly higher or lower than that of the signal, it might be related to the location of hair cell loss in the cochlea. 4. In animals for which damage was restricted to only three rows of outer hair cells, changes of the CAP tuning curves were observed. It provides further evidence that the tuning properties of cochlear nerve fibers are dependent upon the integrity of the outer hair cells even though the great majority of fibers innervate inner hair cells only.

Animals↗

Gasoline explosions, gasoline sniffing: an epidemic in young adolescents.

One hundred twenty-two patients between the ages of 10 and 15 were admitted to the Shriners Burns Institute between July 1981 and November 1984. Seventy-five of the 122 patients sustained burns as a direct result of liquid gasoline explosions. Thirty patients had thrown gasoline on a fire and 17 others admitted to having ignited gasoline with a match. During admission interviews, none of the patients admitted to gasoline sniffing; however, 19 patients were subsequently found to have been sniffing gasoline at the time of the accident. All of the patients with gasoline burns sustained much larger burns, had longer hospitalizations, and required more surgery than did patients burned by other means. Similarly, the 19 patients who had been sniffing gasoline had larger burns, had longer hospital stays, and required more surgery than did those injured by gasoline in other accidents. The most common cause of thermal injury in the ten-to-15 year age group is a gasoline-related accident. The histories of a large number of these adolescents may be compatible with explosions related to gasoline sniffing. Educational efforts relating to the explosive nature of the substance and the dangers of gasoline sniffing are warranted.

Adolescent↗

[Evaluation of exposure level in the handling of explosives].

For the clarification of a supposed case of poisening by handling of explosives containing nitric acid ester in a man who was an expert in performing explosions the proof of the exposition was necessary. By the determination of free nitrite in the blood as well as by measuring of blood pressure and pulse in persons exposed in the same way the intake of nitrated constituents of the explosive could be made clear. The advantage of the determination of free nitrite in the blood in contrast to the determination of the met-Hb is discussed. It is referred to an additional potential endangering by gun fumes and the measures for the protection of labour which are to be derived from this.

Adult↗

[Ensuring safety from explosions in the operating room].

To prevent explosions and fires in operating room the possible reasons for their appearance were considered. The most dangerously explosive zones were classified, and recommendations were given concerning the equipment for these zones to avoid explosive situations.

Explosions↗

Low-mass ions observed in plasma desorption mass spectrometry of high explosives

The low-mass ions observed in both positive and negative plasma desorption mass spectrometry (PDMS) of the high explosives HMX, RDX, CL-20, NC, PETN and TNT are reported. Possible identities of the most abundant ions are suggested and their presence or absence in the different spectra is related to the properties of the explosives as matrices in PDMS. The detection of abundant NO+ and NO2- ions for HMX, RDX and CL-20, which are efficient matrices, indicates that explosive decomposition takes place in PDMS of these three substances and that a contribution from the corresponding chemical energy release is possible. The observation of abundant C2H4N+ and CH2N+ ions, which have high protonation properties, might also explain the higher protein charge states observed with these matrices. Also, the observation of NO2-, possibly formed by electron scavenging which increases the survival probability of positively charged protein molecular ions, completes the pattern. TNT does not give any of these ions and it is thereby possible to explain why it does not work as a PDMS matrix. For NC and PETN, decomposition does not seem to be as pronounced as for HMX, RDX and CL-20, and also no particularly abundant ions with high protonation properties are observed. The fact that NC works well as a matrix might be related to other properties of this compound, such as its high adsorption ability.

Journal Article↗

Analysis of explosives via microchip electrophoresis and conventional capillary electrophoresis: a review.

The upsurge in terrorist activity has generated tremendous demand for innovative tools capable of detecting major industrial, military, and home-made (improvised) explosives. Fast, sensitive, and reliable detection of explosives in the field is a very important issue in nowadays. CE, especially in its miniaturized format (lab-on-a-chip), offers great possibilities to create portable, field deployable, rapidly responding, and potentially disposable devices, allowing security forces to make the important decisions regarding the safety of civilians. This article overviews the microchip and conventional capillary electrophoretic techniques for analysis of a wide variety of explosive compounds and mixtures.

Chemical Terrorism↗

Explosive autotomy induced by simultaneous dorsal column lesion and limb denervation: a possible model for acute deafferentation pain.

We report on a new "explosive" form of self-mutilation behavior (autotomy) characterized by rapid onset (1-2 days), short duration (1-2 days), and unpredictable progression. The possible neural mechanism(s) underlying this novel behavior were examined in rats by combining at varying time intervals one leg denervation with a lesion to the dorsal columns (DC lesion) or to a dorsolateral funiculus (DLF lesion). DC lesion, followed immediately by leg denervation, resulted in explosive autotomy in 62% of the rats and regular autotomy in 25% of the rats. Regular autotomy was characterized by slow onset (2-3 weeks), prolonged duration (2-3 weeks), and stereotyped progression from distal to proximal parts of the leg. DC lesion, followed 1 week later by leg denervation, resulted in regular autotomy in 71% of the rats which was not different from autotomy resulting from denervation alone. DC lesion preceded 1 week earlier by leg denervation resulted in slightly accelerated regular autotomy in 77% of the rats. Simultaneous DC lesion and leg denervation immediately preceded by application of a local anesthetic (4% procaine) for 30 or 60 min to the exposed lumbar spinal cord resulted in regular autotomy in all rats. All rats in a sham group, in which the procaine was replaced by normal saline, exhibited explosive autotomy. DLF lesion, followed immediately by leg denervation, resulted in accelerated regular autotomy.(ABSTRACT TRUNCATED AT 250 WORDS)

Afferent Pathways↗

The contribution of muscle properties in the control of explosive movements.

Explosive movements such as throwing, kicking, and jumping are characterized by high velocity and short movement time. Due to the fact that latencies of neural feedback loops are long in comparison to movement times, correction of deviations cannot be achieved on the basis of neural feedback. In other words, the control signals must be largely preprogrammed. Furthermore, in many explosive movements the skeletal system is mechanically analogous to an inverted pendulum; in such a system, disturbances tend to be amplified as time proceeds. It is difficult to understand how an inverted-pendulum-like system can be controlled on the basis of some form of open loop control (albeit during a finite period of time only). To investigate if actuator properties, specifically the force-length-velocity relationship of muscle, reduce the control problem associated with explosive movement tasks such as human vertical jumping, a direct dynamics modeling and simulation approach was adopted. In order to identify the role of muscle properties, two types of open loop control signals were applied: STIM(t), representing the stimulation of muscles, and MOM(t), representing net joint movements. In case of STIM control, muscle properties influence the joint moments exerted on the skeleton; in case of MOM control, these moments are directly prescribed. By applying perturbations and comparing the deviations from a reference movement for both types of control, the reduction of the effect of disturbances due to muscle properties was calculated. It was found that the system is very sensitive to perturbations in case of MOM control; the sensitivity to perturbations is markedly less in case of STIM control. It was concluded that muscle properties constitute a peripheral feedback system that has the advantage of zero time delay. This feedback system reduces the effect of perturbations during human vertical jumping to such a degree that when perturbations are not too large, the task may be performed successfully without any adaptation of the muscle stimulation pattern.

Computer Simulation↗

Effects of explosive type strength training on physical performance characteristics in cross-country skiers.

To investigate the effects of a combination of simultaneous strength and endurance training on selected neuromuscular and aerobic performance characteristics seven male cross-country skiers underwent training for a period of 6 weeks. The experimental group trained 6-9 times per week with a programme consisting of 34% explosive type strength training and 66% endurance training during the first 3 weeks of the experiment and 42% and 58% respectively during the last 3 weeks of the experiment. The total volume of training of the control group (eight skiers) was of the same magnitude but consisted of 85% pure endurance training and 15% endurance type strength training. The experimental training regime resulted in specific changes in neuromuscular performance. This was demonstrated by improvements (P less than 0.01) in the maximal heights of rise of the centre of gravity in the squat and countermovement jumps. A significant decrease (P less than 0.05) took place also in the time of rapid isometric force production during experimental training, while no changes occurred in the maximal force of the trained muscles. Aerobic performance characteristics of the experimental group did not change during the experimental training period. No significant changes occurred in neuromuscular or aerobic performance characteristics in the control group. These findings indicated that training-induced improvements in explosive force production may not be fully inhibited by this kind of aerobic training. They also suggested that endurance athletes could undertake explosive type strength training programmes without a concomitant reduction in aerobic capacity, if the overall loading of training were within predefined limits.

Adult↗

Recent methods for the determination of peroxide-based explosives.

In the last few years, the need to determine peroxide-based explosives in solid samples and air samples has resulted in the development of a series of new analytical methods for triacetonetriperoxide (TATP, acetone peroxide) and hexamethylenetriperoxidediamine (HMTD). In this review, after a short introduction describing the state of the art in the field, these new analytical methods are critically discussed. Particular emphasis is placed on spectroscopic and mass spectrometric methods as well as on chromatographic techniques with selective detection schemes. The potential of these methods to analyse unknown solid samples that might contain one or more of the explosives and to analyse peroxide-based explosives in air is evaluated.

Journal Article↗

Biodegradation of the cyclic nitramine explosives RDX, HMX, and CL-20.

Cyclic nitramine explosives are synthesized globally mainly as military munitions, and their use has resulted in environmental contamination. Several biodegradation pathways have been proposed, and these are based mainly on end-product characterization because many of the metabolic intermediates are hypothetical and unstable in water. Biodegradation mechanisms for cyclic nitramines include (a) formation of a nitramine free radical and loss of nitro functional groups, (b) reduction of nitro functional groups, (c) direct enzymatic cleavage, (d) alpha-hydroxylation, or (e) hydride ion transfer. Pathway intermediates spontaneously decompose in water producing nitrite, nitrous oxide, formaldehyde, or formic acid as common end-products. In vitro enzyme and functional gene expression studies have implicated a limited number of enzymes/genes involved in cyclic nitramine catabolism. Advances in molecular biology methods such as high-throughput DNA sequencing, microarray analysis, and nucleic acid sample preparation are providing access to biochemical and genetic information on cultivable and uncultivable microorganisms. This information can provide the knowledge base for rational engineering of bioremediation strategies, biosensor development, environmental monitoring, and green biosynthesis of explosives. This paper reviews recent developments on the biodegradation of cyclic nitramines and the potential of genomics to identify novel functional genes of explosive metabolism.

Amines↗