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PubMedDate not supplied

Electrical injuries: a 20-year review.

Electrical injuries continue to present problems with devastating complications and long-term socioeconomic impact. The purpose of this study is to review one institution's experience with electrical injuries. From 1982 to 2002, there were 700 electric injury admissions. A computerized burn registry was used for data collection and analysis. Of these injuries, 263 were high voltage (> or =1000 V), 143 were low voltage (<1000 V), 277 were electric arc flash burns, and 17 were lightning injuries. Mortality was highest in the lightning strikes (17.6%) compared with the high voltage (5.3%) and low voltage (2.8%) injuries, and mortality was least in electric arc injuries without passage of current through the patient (1.1%). Complications were most common in the high-voltage group. Mean length of stay was longest in this group (18.9 +/- 1.4 days), and the patients in this group also required the most operations (3 +/- 0.2). Work-related activity was responsible for the majority of these high-voltage injuries, with the most common occupations being linemen and electricians. These patients tended to be younger men in the prime of their working lives. Electrical injuries continue to make up an important subgroup of patients admitted to burn centers. High-voltage injuries in particular have far reaching social and economic impact largely because of the patient population at greatest risk, that is, younger men at the height of their earning potential. Injury prevention, although appropriate, remains difficult in this group because of occupation-related risk.

Accidents, Occupational↗
PubMed1996

Radio Frequency Signals in Jupiter's Atmosphere

During the Galileo probe's descent through Jupiter's atmosphere, under the ionosphere, the lightning and radio emission detector measured radio frequency signals at levels significantly above the probe's electromagnetic noise. The signal strengths at 3 and 15 kilohertz were relatively large at the beginning of the descent, decreased with depth to a pressure level of about 5 bars, and then increased slowly until the end of the mission. The 15-kilohertz signals show arrival direction anisotropies. Measurements of radio frequency wave forms show that the probe passed through an atmospheric region that did not support lightning within at least 100 kilometers and more likely a few thousand kilometers of the descent trajectory. The apparent opacity of the jovian atmosphere increases sharply at pressures greater than about 4 bars.

Journal Article↗
PubMed2006

Electrical injury and amyotrophic lateral sclerosis: a systematic review of the literature.

Electrical injury may act as a potential precipitating or risk factor for amyotrophic lateral sclerosis (ALS). A systematic review of the literature was undertaken to assess the relationship between electrical injury and the development of ALS. Information for the review was obtained using five medical databases, and from manual searching of individual papers. Patients presenting with a neurological syndrome after electrical injury, including lightning, were included and classified into four categories: ALS; progressive upper motor neurone (UMN) syndrome; progressive lower motor neurone (LMN) syndrome; and non-progressive syndrome. Linear regression and chi2 testing were used for analysis of the data. 96 individuals, comprising 44 with ALS, 1 with a progressive UMN syndrome, 7 with a progressive LMN syndrome and 44 with a non-progressive syndrome, were identified from 31 papers with publication dates between 1906 and 2002. The median interval between electrical injury and disease onset was 2.25 years for all progressive syndromes and just over 1 week for the non-progressive syndrome. The more severe the shock (excluding lightning), the more likely individuals were to have a non-progressive motor syndrome. A non-progressive spinal cord syndrome is associated with more severe electrical injury. Overall, the evidence reviewed does not support a causal relationship between ALS and electric shock.

Amyotrophic Lateral Sclerosis↗
PubMed1995

Artefacts due to static electricity in a dental school.

The diagnostic usefulness of radiographs is diminished by errors of film handling, and retakes mean increased radiation doses. Avoiding artefacts due to static electricity is part of a quality assurance programme. The number of types of artefacts originating from static electricity in the Department of Radiology, School of Dentistry, Copenhagen, were recorded over a five-week period with low temperatures and low air humidity. During the period 3137 intra-oral and 638 extra-oral films were processed by seven assistants and a number of trainees. A total of 48 artefacts on 47 extra-oral films was observed. The artefacts were classified into four types. Only one case of classical 'lightning' was found, while nine were of a hitherto undescribed type ('animals' or 'cactus flowers'). The most common type appeared as dots arranged in straight lines; their origin was obscure, but it was suspected that they were caused by the processing machine. The one typical 'lightning' case occurred on a Status-X film, consistent with the theory that friction may be a causative factor. Although individual frequencies varied, all the radiography assistants and trainees were associated with the artefacts recorded.

Artifacts↗
PubMedDate not supplied

[Primary mixed unilateral algias (author's transl)].

Usually trigeminal neuralgia or tic douloureux and migrainous neuralgia or cluster headache are sharply opposed. But some rare cases of mixed facial unilateral algias associating both mechanisms are possible. Here is studied a series of 12 cases. One may distinguish: 1. one neuralgic vascular type. It starts by lightning and triggered hemifacial pain followed by tenderness and vaso-secretory phenomenous of same topography; 2. the second is of vascular-neuralgic type. It starts like common cluster headache; the lightning pain occuring in the end of paroxysm. Only the first type -- neuralgic vascular -- is reactive to chimiotherapy (carbamazepine) or local antinevralgic procedures (thermocoagulation).

Adult↗
PubMed1997

An unusual case of death by lighting.

Lightning-related deaths are relatively uncommon, especially indoors. Some cases, involving unusual circumstances, may be of medicolegal relevance. We report a highly infrequent case of fulguration occurring inside a house in a country area. The deceased, a 55-year-old man, was struck by lightning while he was in his bed. Scene investigation and autopsy findings were equally important in finding out the cause of death. We think that the present case is of interest to forensic pathologists because what occurred might be difficult to clarify.

Disasters↗
PubMed2003

External cause-specific summaries of occupational fatal injuries. Part II: an analysis of years of potential life lost.

BACKGROUND: Fatal injury surveillance data provide an opportunity to assess the impact of occupational injuries and may indicate which industries or occupations are appreciably more hazardous than others, and thus should be given priority in public health intervention. METHODS: Fatalities from the National Traumatic Occupational Fatality surveillance system served as the basis for examining external cause (E-code) specific impact summaries. Years of potential life lost (YPLL) were calculated for fatal injuries in the years 1983-1994. Industries and occupations were compared with respect to frequency of fatal injuries. In addition, injuries in categories of external causes are examined across all industries and occupations. RESULTS: Machinery, electric current, homicide, falls, and transportation-related are the external cause groups highlighted by high frequency/rate of occurrence. Electric current event groups are also characterized by high average YPLL. Poisoning, conflagration, and lightning were also identified in several occupations as having high associated average YPLL. CONCLUSIONS: The external-cause-specific analysis of average YPLL identified industries and occupations where, on average, younger workers were dying in fatal injuries. Noteworthy in this assessment were homicides and falls. The YPLL measure coupled with more commonly employed indices (e.g., rates) may provide a fuller description of the impact of occupational fatal injuries.

Accidental Falls↗
PubMed2000

Community dynamics: what happens when we rerun the tape?

The role of historical events, such as disturbances, in producing alternative developmental outcomes in forest structure has long been debated. Diversity in the assemblages of coexisting species is one measure of alternative outcomes of succession. The intermediate disturbance hypothesis proposes that a moderate disturbance level produces the highest levels of species diversity. Here, we use an agent-based model of forest development under a gradient of lightning strike frequency to analyse long-term dynamics of species coexistence in a multi-species forest. The configurations of species that result from disturbance dynamics reflect the interactions between life-history characteristics of the species and disturbance characteristics. Model results suggest that low levels of disturbance lead to highly ordered landscapes which exclude fire and are captured by late successional species. High levels of disturbance lead to oscillation between domination by early successional species and large disturbances. At intermediate levels of disturbance, the forest displays the broadest array of developmental pathways, highest entropy as measured by Shannon's index of diversity, and critical slowing near steady states. Long transients at intermediate regimes may reflect the working out of closely balanced constraints of competition between species with varying strategic adaptations to disturbance. Intermediate disturbance levels also result in the greatest number of alternative diversity configurations as outcomes of succession, reflecting an unpredictable and nonequilibrium forest dynamic.

Animals↗
PubMed1988

The evolution of nitrogen cycling.

Based upon arguments concerning properties of the environment and the energetics of nitrogen transformation reactions, new hypotheses regarding their evolution are presented. These hypotheses are supported by new calculations and observations germane to understanding the evolution of the nitrogen cycle. From calculations of shock production by meteor impact, we suggest that impact produced fixed nitrogen could have resulted in the entire reservoir of Earth's N2 being converted into fixed nitrogen at the end of accretion. We have significantly improved upon previous calculations of the abiotic fixation rate on the early earth and find a rate of fixation by lightning of approximately 1-3 x 10(16) molecules NO/J, which is 2 to 3 times greater than previous estimates. This strengthens the suggestion, corroborated by the predominance of a single nitrogenase enzyme, that biological nitrogen fixation may have been a late evolutionary development, after the development of an aerobic atmosphere. In addition, we show for the first time that HNO, predicted to be the main product of atmospheric photochemical reactions involving NO on the primitive Earth by photochemical models, would eventually become NO2- and NO3- after reaching the Earth's surface. Based upon microbe-environment interactions on an ecological as well as a biochemical scale we suggest that denitrification arose prior to aerobic respiration and that nitrification arose after the advent of an aerobic atmosphere. We hypothesize the following evolutionary sequence for the biological transformation of nitrogen compounds: Ammonification --> Denitrification --> Nitrification --> Nitrogen fixation.

Ammonia↗
PubMed2005

Nitrogen fixation by corona discharge on the early precambrian Earth.

We report the first experimental study of nitrogen fixation by corona discharge on the anoxic primitive Earth. The energy yields of nitric oxide (NO) and nitrous oxide (N(2)O) were experimentally determined over a wide range of CO(2)-N(2) mixtures simulating the evolution of the Earth's atmosphere during the Hadean and Archean eras (from 4.5 ba to 2.5 ba). NO, the principal form of fixed nitrogen in lightning and coronal discharge in early Earth, is produced ten times less efficiently in the latter type of electrical discharge with an estimated maximum annual production rate of the order of 10(10) g yr(-1). For N(2)O the maximum production rate was estimated to be approximately 10(9) g yr(-1). These low rates of syntheses indicate that corona discharges as point discharges on the clouds and ground did not play a significant role in the overall pool of reactive nitrogen needed for the emergence and sustainability of life.

Atmosphere↗
PubMed2001

Electric currents induced inside biological cells by geomagnetic and atmospheric phenomena.

An increasing number of studies have appeared in the last ten years indicating that some pathologies may correlate with geomagnetic activity and cosmic rays. However a physical mechanism binding both phenomena has not been proposed. In the present work we obtain the amplitude of the magnetic fields at different frequencies, that may induce inside biological cells currents of the same magnitude of the currents generated by the cells themselves. We compare these values with the wave amplitudes produced in geomagnetic and atmospheric phenomena, and found that micropulsations, whistlers and lightning are capable of produce the same or larger values.

Cell Physiological Phenomena↗
PubMed1999

Chemical reduction of phosphate on the primitive earth.

If phosphorus played a role in the origin of life, some means of concentrating micromolar levels of phosphate (derived from the calcium phosphate mineral apatite), must first have been available. Here we show that simulated (mini)lightning discharges in model prebiotic atmospheres, including only minimally reducing ones, reduce orthophosphates, including apatite, to produce substantial yields of phosphite. Electrical discharges associated with volcanic eruptions could have provided a particularly suitable environment for this process. Production of relatively soluble and reactive phosphite salts could have supplied a pathway by which the first phosphorus atoms were incorporated into (pre)biological systems.

Apatites↗
PubMed1987

HCN and chromophore formation on Jupiter.

The formation of HCN and chromophores are two of the major unsolved problems of the atmospheric chemistry of Jupiter. The question to be dealt with is the same in each case: how can these unsaturated organic compounds be formed in the highly reducing atmosphere (89% H2) present on Jupiter? The photolysis of ammonia/acetylene mixtures provides an answer to this question. Here we report the formation of both HCN and chromophores along with experimental data which support the premise that this photochemical process provides a route for the formation of both substances. It is not clear whether significant amounts of HCN are also formed by lightning on Jupiter.

Acetylene↗
PubMed1982

[Is cardiac monitoring required after electrical injuries? (author's transl)].

Professional or spare time contacts with electrical appliances are, due to careless handling or technical inadequacies, potentially always associated with electrical injuries. The effects of the electric current on the body depends mainly on voltages: skin and muscle lesions predominate in high voltage injuries. Out of 23 patients, 19 with electrical injuries and 4 with lightning accidents, 18 showed normal ECGs at the time of hospital admission. There were no changes at follow-up. The remaining 5 patients had cardiac arrhythmias which disappeared after 1 1/2 to 36 hours using bedrest and symptomatic treatment only. Cardiac longterm monitoring is thus not required after electrical injuries.

Adult↗
PubMed1990

Children's defensive responses and emotional upset following a disaster: a projective assessment.

Projective stories were used to assess the defense mechanisms of 27 preadolescent boys who were victims of a lightning strike in which one boy died. Denial, projection, and identification, in combination, were found to be inversely related to clinical upset, as was the age and sex-appropriate individual defense of projection. In addition, low-defensive boys' self-reports of fears agreed more often with their parents' reports of sleep and somatic disturbances than did high-defensive boys' self-reports. The findings provide support for the validity of the Defense Mechanism Manual (Cramer, 1982) and raise the issue of defense mechanisms as moderator variables in self-report questionnaires.

Adaptation, Psychological↗
PubMed2001

Asthma admissions and thunderstorms: a study of pollen, fungal spores, rainfall, and ozone.

Asthma admissions have been reported to increase during thunderstorms. In some cases, this has been attributed to rises in pollen or fungal spore counts occurring alone or in combination with rainfall. We tested the hypothesis that thunderstorms in general are associated with asthma admissions, and investigated the possible roles of pollen, fungal spores, ozone, and other meteorological factors. We obtained data on multiple pollen and fungal spore counts, rainfall, temperature, ambient ozone concentrations, and asthma admissions for 32 dates when lightning strikes were recorded in the Cardiff/Newport area, and 64 matched dates in previous and subsequent years. Poisson regression models were used to investigate associations between admissions and proposed causative environmental factors. The number of asthma admissions was greater on days with thunderstorms than on control days (p<0.001). There were no associations or interactions between admissions and any pollen or fungal spore counts or rainfall. After adjusting for thunderstorms, there was an independent association between increasing ozone concentration, when temperature was included in the model, and increasing admissions (p=0.02). Asthma admissions are increased during thunderstorms. The effect is more marked in warmer weather, and is not explained by increases in grass pollen, total pollen or fungal spore counts, nor by an interaction between these and rainfall. There was an independent, positive association between ozone concentrations and asthma admissions.

Allergens↗
PubMed2002

Mass casualties and triage at a sporting event.

When a sports medicine doctor provides coverage for a sporting event with a large number of athletes and spectators, he or she should always be aware that the potential for a large number of injuries exists. In the event of a mass casualty incident that overwhelms the available medical resources, he or she may be the most qualified professional present to triage and organise patient care. Certain basic rules of triage in a disaster situation should be followed, the goal being to save as many lives as possible. Special circumstances, such as crush injuries, lightning strikes, and blast injuries, may affect the triage and initial care of injured patients.

Blast Injuries↗
PubMed1997

Effect of thunderstorms and airborne grass pollen on the incidence of acute asthma in England, 1990-94.

BACKGROUND: Thunderstorms and prior grass pollen counts were investigated as predictors of daily hospital admissions for asthma in England. This study was motivated by reports in the literature of spectacular asthma epidemics associated with thunderstorms, particularly in the grass pollen season. METHODS: Asthma admissions for two age groups (0-14 years and 15 and over) were measured using the Hospital Episodes System (HES) in the 14 regional health authorities (RHAs) in England. Thunderstorms were measured daily in each RHA using densities of sferics (lightning flashes). Relative asthma excesses for moderate positive and exceptionally high sferic densities, with or without previous high grass pollen counts, were measured using log linear autoregression--allowing for weekly, seasonal, and longer term background variation--and pooled over RHAs by calculating geometric means. RESULTS: Relative risks from all RHAs were pooled to form geometric means. Exceptional sferic densities were associated with a relative excess risk of around 25% in both age groups. Moderate sferic densities were associated with a smaller excess, statistically significant in the two age groups taken together. In five RHAs in which grass pollen counts were available, high pollen counts for the previous five days were associated with an amplification of the excess associated with thunderstorms. CONCLUSION: Very large sferic densities are associated with moderate rises in hospital admissions for acute asthma. However, typical thunderstorm days are not associated with spectacular asthma epidemics of the scale previously reported in the literature. Thunderstorm-associated excesses are amplified after a run of high pollen counts.

Acute Disease↗