Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
1.
Ideggyogy Sz ; 77(3-4): 137-139, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38591923

RESUMO

Peripheral nerve injuries after being struck by lightning have been documented. Here, we report a case of cauda equina syndrome induced by lightning. A 27-year-old man presented with numbness, a burning sensation in the saddle region, and increased urinary urgency after being struck by lightning. He had absent Achilles reflexes and paresthesia in the saddle region upon neurological examination, and magnetic resonance imaging of the spine was normal. Electrophysiological studies indicated involvement of bilateral L5, S1, and S2 myotomes and revealed cauda equina lesions. 
Peripheral nerve injury induced by lightning is rare, and the evaluation of people with neurological complaints using electromyography will help determine the true incidence.

.


Assuntos
Síndrome da Cauda Equina , Cauda Equina , Lesões por Ação do Raio , Masculino , Humanos , Adulto , Síndrome da Cauda Equina/etiologia , Síndrome da Cauda Equina/patologia , Lesões por Ação do Raio/complicações , Lesões por Ação do Raio/patologia , Eletromiografia , Cauda Equina/diagnóstico por imagem , Cauda Equina/patologia , Imageamento por Ressonância Magnética
2.
Materials (Basel) ; 17(3)2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38591613

RESUMO

Lightning strike events pose significant challenges to the structural integrity and performance of composite materials, particularly in aerospace, wind turbine blade, and infrastructure applications. Through a meticulous examination of the state-of-the-art methodologies of laboratory testing and damage predictive modeling, this review elucidates the role of simulated lightning strike tests in providing inputs required for damage modeling and experimental data for model validations. In addition, this review provides a holistic understanding of what is there, what are current issues, and what is still missing in both lightning strike testing and modeling to enable a robust and high-fidelity predictive capability, and challenges and future recommendations are also presented. The insights gleaned from this review are poised to catalyze advancements in the safety, reliability, and durability of composite materials under lightning strike conditions, as well as to facilitate the development of innovative lightning damage mitigation strategies.

4.
Eur Heart J Case Rep ; 7(11): ytad578, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38034938

RESUMO

Background: Direct lightning strikes are rare, and multiple organ systems can be involved. Prognosis is dependent on the severity of the injury. Severe myocardial injury associated with transient electrocardiogram changes, which have been previously described, is a hazardous complication. Case summary: A 35-year-old man with no known past medical history presented unresponsive following a direct lightning strike while sitting in a portable toilet. High-quality cardiopulmonary resuscitation was started in the field, with return of spontaneous circulation (ROSC) after 1 h. Following ROSC, he received volume resuscitation and was maintained on multiple vasopressors. Electrocardiogram showed significant ST-elevations in inferior leads with elevated troponin I, consistent with inferior ST-elevation myocardial infarction. Labs revealed lactic acidosis, hyperkalaemia, acute kidney, and liver injury. Due to concern for plaque rupture, coronary angiography was performed and revealed no obstructive coronary artery disease. Vasopressor support and volume resuscitation were continued for extensive burns covering greater than 30% body surface area. The patient became progressively hypotensive, eventually precipitating pulseless electrical activity arrest. Emergent labs were notable for severe acidaemia. Despite aggressive interventions, he expired due to severe multi-organ failure. Discussion: Direct lightning injuries are rare with serious potential complications. Myocardial damage, either from direct electrical insult or from induced coronary vasospasm, can lead to multi-organ system failure.

6.
Materials (Basel) ; 16(11)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37297046

RESUMO

Polymer-matrix composites are widely used in engineering applications. Yet, environmental factors impact their macroscale fatigue and creep performances significantly, owing to several mechanisms acting at the microstructure level. Herein, we analyse the effects of water uptake that are responsible for swelling and, over time and in enough quantity, for hydrolysis. Seawater, due to a combination of high salinity and pressures, low temperature and biotic media present, also contributes to the acceleration of fatigue and creep damage. Similarly, other liquid corrosive agents penetrate into cracks induced by cyclic loading and cause dissolution of the resin and breakage of interfacial bonds. UV radiation either increases the crosslinking density or scissions chains, embrittling the surface layer of a given matrix. Temperature cycles close to the glass transition damage the fibre-matrix interface, promoting microcracking and hindering fatigue and creep performance. The microbial and enzymatic degradation of biopolymers is also studied, with the former responsible for metabolising specific matrices and changing their microstructure and/or chemical composition. The impact of these environmental factors is detailed for epoxy, vinyl ester and polyester (thermoset); polypropylene, polyamide and poly etheretherketone (thermoplastic); and for poly lactic acid, thermoplastic starch and polyhydroxyalkanoates (biopolymers). Overall, the environmental factors mentioned hamper the fatigue and creep performances, altering the mechanical properties of the composite or causing stress concentrations through microcracks, promoting earlier failure. Future studies should focus on other matrices beyond epoxy as well as on the development of standardised testing methods.

7.
Materials (Basel) ; 16(4)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36837379

RESUMO

An airplane is statistically struck by lightning every year. The need for lightweight aircraft to reduce the production of carbon dioxide has significantly reduced the presence of metals in favour of composites, resulting in lower lightning strike protection efficiency. In this perspective, we critically review the state of technologies in lightning strike protection solutions based on carbon materials, graphene, and MXenes. Furthermore, we comment on possible future research directions in the field.

8.
Forensic Sci Med Pathol ; 19(2): 139-145, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35930215

RESUMO

In this study, deaths from lightning strikes in Eastern Turkey revealed distinct patterns in lifestyle and physical injury. Farmers, sailors, and those engaged in outdoor sports are all at risk of being struck by lightning. Death from a lightning strike is associated with cardiovascular and central nervous system damage. This study examines cases of autopsies that were performed on bodies that had suffered a lightning strike, including sociodemographic data, burns on the body, injured regions, histopathological findings, and causes of death. This retrospective evaluation included 17 cases. The cases comprised 88.2% males and 11.8% females, with a mean age of 41.5 years. The person's occupation was farmer in 29.4% of the cases and shepherd in 70.6%. Their deaths occurred most frequently in the summer months. Deaths associated with lightning strikes are more frequent in east of Turkey than in other regions, as agriculture and livestock are common sources of income. The majority of the victims among the cases were males working outside because of their occupations. Histopathologically, subarachnoid fresh bleeding was seen in five cases, subpleural fresh bleeding in the lungs in five cases, and interlobular rupture in the lungs in three cases. Deaths associated with lightning strikes have been correlated with a low level of education in this subject. This study is the largest case study of deaths associated with lightning strikes in Turkey.


Assuntos
Lesões por Ação do Raio , Relâmpago , Militares , Masculino , Feminino , Humanos , Adulto , Lesões por Ação do Raio/patologia , Estudos Retrospectivos , Turquia/epidemiologia
9.
J Med Case Rep ; 16(1): 391, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36271452

RESUMO

BACKGROUND: Lightning strike is a rare but dramatic cause of injury. Patients admitted to intensive care units (ICUs) with lightning strike frequently have a high mortality and significant long-term morbidity related to a direct brain injury or induced cardiac arrest (CA). CASE PRESENTATION: A 50-year-old Caucasian man was admitted to our hospital after being struck by lightning resulting in immediate CA. Spontaneous circulation was initially restored, and the man was admitted to the ICU, but ultimately died while in hospital due to neurological injury. The computer tomography scan revealed a massive loss of grey-white matter differentiation at the fronto-temporal lobes bilaterally. Somatosensory-evoked potentials demonstrated bilateral absence of the cortical somatosensory N20-potential, and the electroencephalogram recorded minimal cerebral electrical activity. The patient died on day 10 and a post-mortem study revealed a widespread loss of neurons. CONCLUSION: This case study illustrates severe brain injury caused by a direct lighting strike, with the patient presenting an extraordinary microscopic pattern of neuronal desertification.


Assuntos
Lesões Encefálicas , Lesões por Ação do Raio , Relâmpago , Humanos , Pessoa de Meia-Idade , Lesões por Ação do Raio/complicações , Conservação dos Recursos Naturais , Neurônios
10.
Naturwissenschaften ; 109(4): 33, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35687146

RESUMO

Conventional oligopeptide synthesis techniques involve environmentally harmful procedures and materials. In addition, the efficient accumulation of oligopeptides under Hadean Earth environments regarding the origin of life remains still unclear. In these processes, the formation of diketopiperazine is a big issue due to the strong inhibition for further elongation beyond dipeptides. Hydrothermal media enables environmentally friendly oligopeptide synthesis. However, hydrothermal oligopeptide synthesis produces large amounts of diketopiperazine (DKP), due to its thermodynamic stability. DKP inhibits dipeptide elongation and also constitutes an inhibitory pathway in conventional oligopeptide synthesis. Here, we show an efficient pathway for oligopeptide formation using a specially designed experimental setup to run both thermal and non-thermal discharge plasma, generated by nano-pulsed electric discharge with 16-23 kV voltage and 300-430 A current within ca. 500 ns. DKP (14%) was converted to dipeptides and higher oligopeptides in an aqueous solution containing alanine-DKP at pH 4.5, after 20 min of 50 pps thermal plasma irradiation. This is the first study to report efficient oligopeptide synthesis in aqueous medium using nano-pulsed plasma (with thermal plasma being more efficient than non-thermal plasma) via DKP ring-opening. This unexpected finding is implicative to evaluate the pathway how the oligopeptides could have accumulated in the primitive Earth with high-energy plasma sources such as thunder as well as to facilitate the green synthesis of oligopeptides.


Assuntos
Dicetopiperazinas , Gases em Plasma , Dipeptídeos , Oligopeptídeos , Água
11.
Leg Med (Tokyo) ; 58: 102099, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35752059

RESUMO

The lightning strike is one of leading cases of weather-related death worldwide. We present an unusual case of four fatality-lightning strike with various pathological manifestations. All victims died from a single lightning strike in the mountains that also caused injury to 156 other people. All victims had mechanical damage and rock damage that are typical for lightning strikes in the mountainside. Another lesions indicative of lightning strike and electrical damage were, among others: burnt and torn clothes (all cases) current marks (Cases 1, 2 and 3) and Lichtenberg figures along with flashover marks on Case 1. In the review we described the pathophysiological mechanisms of lightning-induced lesions and injuries and epidemiological trends of lightning-strike deaths. Our study exemplifies various manifestations of lightning strikes on forensic examination and underlines the necessity to take lightning strike into consideration when investigating open-air deaths of unclear origin.


Assuntos
Lesões por Ação do Raio , Humanos , Lesões por Ação do Raio/patologia
12.
Materials (Basel) ; 14(18)2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34576430

RESUMO

While carbon-fiber-reinforced polymers (CFRPs) are widely used in the aerospace industry, they are not able to disperse current from lightning strikes because their conductivity is relatively low compared to metallic materials. As such, the undispersed current can cause the vaporization or delamination of the composites, threatening aircraft safety. In this paper, finite element models of lightning damage to CFRPs were established using commercial finite element analysis software, Abaqus, with the user-defined subroutines USDFLD and HEAVEL. The influences of factors such as the structural geometry, laminate sequence, and intrinsic properties of CFRPs on the degree of damage to the composites are further discussed. The results showed that when a current from lightning is applied to the CFRP surface, it mainly disperses along the fiber direction in the outermost layer. As the length of the CFRP increases, the injected current has a longer residence time in the material due to the increased current exporting distance. Consequently, larger amounts of current accumulate on the surface, eventually leading to more severe damage to the CFRP. This damage can be alleviated by increasing the thickness of the CFRP, as the greater overall resistance makes the CFRP a better insulator against the imposed current. This study also found that the damaged area increased as the angle between the first two layers increased, whereas the depth of the damage decreased due to the current dispersion between the first two layers. The analysis of the electrical conductivity of the composite suggested that damage in the fiber direction will be markedly reduced if the conductivity in the vertical fiber direction increases approximately up to the conductivity of the fiber direction. Moreover, increasing the thermal conductivity along the fiber direction will accelerate the heat dissipation process after the lightning strike, but the influence of the improved thermal conductivity on the extent of the lightning damage is less significant than that of the electrical conductivity.

13.
Materials (Basel) ; 14(11)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200475

RESUMO

The main aim of this work was the investigation of the possibility of replacing the heavy metallic meshes applied onto the composite structure in airplanes for lightning strike protection with a thin film of Tuball single-wall carbon nanotubes in the form of ultra-light, conductive paper. The Tuball paper studied contained 75 wt.% or 90 wt.% of carbon nanotubes and was applied on the top of carbon fibre reinforced polymer before fabrication of flat panels. First, the electrical conductivity, impact resistance and thermo-mechanical properties of modified laminates were measured and compared with the reference values. Then, flat panels with selected Tuball paper, expanded copper foil and reference panels were fabricated for lightning strike tests. The effectiveness of lightning strike protection was evaluated by using the ultrasonic phased-array technique. It was found that the introduction of Tuball paper on the laminates surface improved both the surface and the volume electrical conductivity by 8800% and 300%, respectively. The impact resistance was tested in two directions, perpendicular and parallel to the carbon fibres, and the values increased by 9.8% and 44%, respectively. The dynamic thermo-mechanical analysis showed higher stiffness and a slight increase in glass transition temperature of the modified laminates. Ultrasonic investigation after lightning strike tests showed that the effectiveness of Tuball paper is comparable to expanded copper foil.

14.
West Indian med. j ; 69(1): 60-65, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1341860

RESUMO

ABSTRACT Objective: To report the largest series of lightning-related deaths in Turkey, to review the literature on this subject, and to identify similarities and differences between the autopsy findings in this study and the information available in literature. Methods: In this study, autopsy reports and crime scene investigation data on 11 lightning-related fatalities that occurred in the Van and Hakkâri Provinces, Turkey, from January 1, 2011 to December 31, 2015 were retrospectively reviewed. Results: Of the 1699 fatalities, 11 (2.53%) evaluated by medico-legal autopsy in the Van and Hakkâri Province in a 5-year period died from lightning strikes. Of these cases, 10 (90.1%) were males and 1 (9.9%) was female (p < 0.05). All cases were in the 11 to 33 years age group. All cases were injured outdoors. Conclusion: We concluded that deaths due to lightning strikes are relatively rare in Turkey, and may be reduced with precautions such as avoiding staying under trees or in the vicinity of high towers, refraining from touching metal objects, avoiding lying on the ground, leaning on walls, and crouching outdoors.


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adulto , Lesões por Ação do Raio/mortalidade , Causas de Morte , Autopsia , Turquia , Estudos Retrospectivos
15.
North Clin Istanb ; 8(6): 619-622, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35284794

RESUMO

Lightning strike is a devastating disaster, leading to various life-threating complications and even death. In lightning striking victims, high-voltage electric current can destroy many tissues and organs through various mechanisms. One of these mechanisms is the blunt trauma that injures the organs by creating a blast effect. Although not frequent, blunt trauma may result in various solid organ injuries such as pulmonary contusion. In this article, we reported a 15-year-old male patient who was admitted to the emergency department because of lightning strike in open terrain. Although he was conscious and vital signs were normal at presentation, respiratory distress developed on the 4th day. Unilateral pulmonary contusion was detected on the computerized tomography of the thorax. The patient was treated with supportive oxygen and intravenous hydration therapy. His respiratory distress improved on the 6th day and control posteroanterior chest radiograph revealed that pulmonary hemorrhage was spontaneously resorbed. On the 9th day, he was discharged with normal respiratory findings. The patient did not have any complaints during the 3-month follow-up after discharge.

16.
Materials (Basel) ; 13(22)2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33207815

RESUMO

Coupled electrical-thermal finite element analysis (FEA) models are widely adopted to analyze the thermal ablation damage of carbon fiber reinforced polymer (CFRP) caused by lightning, but it is still difficult to analyze the ablation due to its complex space geometry. According to the principle of computerized tomography (CT), tomographic images of FEA models' temperature fields with different thicknesses were obtained to calculate the mass loss and compare the damage morphology. The four areas including Area 0, Area I, Area II, and Area III; were separated from the temperature fields in terms of different vaporization and pyrolysis temperature ranges of carbon fiber (CF) and resin matrix. Ablation mass losses were calculated by pixel statistics and tomographic intervals, which were consistent with the experimental results. The maximum ablation area of unprotected CFRP was found on the tomography images of 50 µm rather than the surface by comparing tomographic images with different thickness due to the influence of the thermal radiation, but this effect was not found in CFRP protected by copper mesh. Some other phenomena, including continuous evolutions of ablation areas and the influence of the intersection angle on the direction of the ablation extension, were also discovered.

17.
J Investig Med High Impact Case Rep ; 8: 2324709620925566, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32462924

RESUMO

Lightning strikes to people are rare events that cause significant injuries and mortality when they do occur. We describe an uncommon case of a storm chaser in Oklahoma who was struck by lightning who suffered cutaneous burns, bilateral tympanic membrane ruptures, as well as pulmonary edema, which is an atypical finding in survivors. This case report highlights several injury patterns seen in lightning strike cases and provides evidence that these patients should be managed at a center with multidisciplinary services available.


Assuntos
Queimaduras por Corrente Elétrica/etiologia , Lesões por Ação do Raio/complicações , Relâmpago , Edema Pulmonar/etiologia , Adulto , Humanos , Masculino , Oklahoma , Sobreviventes
18.
Sensors (Basel) ; 20(8)2020 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-32325632

RESUMO

In this study, a low-cost surge current detection sensor (SCDS) that can measure high current surges using a low-current toroidal coil is proposed for maintenance of a surge protective device (SPD). The proposed SCDS is designed to display the predicted lifetime of the SPD based on the magnitude of surge current and number of surges. In addition, a method for measuring high surge current using a toroidal coil that can usually measure only low current is proposed. A lightning strike counter consists of a microcontroller with a low-power liquid crystal display (LCD) driver, 3 VDC lithium battery, and signal conditioning circuit that converts amplitude information of the surge current into duration information of a negative pulse to facilitate processing in the microcontroller. In this paper, we propose a software algorithm that can calculate the remaining lifetime of SPD based on the amplitude and number of surge currents. There is also an option to select the capacity of the surge protective device and the number of phase lines, allowing it to assess the predicted lifetime for various types of Class II SPDs. The proposed SCDS is measured as 7.2 µA from the battery power consumption test, and the service life is calculated to be 11.1 years. It meets the International Standard IEC62561-6 test conditions of the lightning strike counter and is expected to be useful in the maintenance of SPDs and lightning protection systems.

19.
Med. UIS ; 32(1): 21-26, ene.-jun. 2019. graf
Artigo em Espanhol | LILACS | ID: biblio-1040391

RESUMO

Resumen Los relámpagos se presentan con una frecuencia mayor a 50 veces por segundo a nivel mundial; sin embargo, las descargas directas suceden rara vez y son responsables del 5% de los eventos fatales. El mecanismo de lesión inicial es la parálisis de los centros vitales, lo que ocasiona apnea, fibrilación auricular o paro cardíaco. En mujeres embarazadas, el accidente por rayo puede producir complicaciones graves, dependiendo del punto de entrada en el cuerpo y su efecto indirecto sobre el feto, produciendo trastornos de la conducción en el sistema cardíaco y daño a nivel del sistema nervioso central. En la literatura mundial, solo catorce casos de embarazo y traumatismo por relámpago han sido reportados, sobreviviendo en todos la madre, con un único reporte de muerte fetal. Se presenta un caso de accidente por relámpago en una mujer embarazada en la semana 23 de gestación, cuyo tipo de lesión fue por contacto directo en el abdomen, y quien ingresó con compromiso neurológico, taquicardia materna y bradicardia fetal. El deceso materno ocurrió por infarto agudo extenso del miocardio y la formación de un émbolo intracavitario en el ventrículo izquierdo, con la consecuente muerte del binomio. Se describe su frecuencia, el mecanismo de lesión, las manifestaciones clínicas y el manejo actual. MÉD.UIS.2019;32(1):21-6


Abstract Lightning occurs with a frequency rate of more than 50 times per second worldwide. Nevertheless, direct lightning strikes are not common, and they are responsible for about 5% of all lightning injury fatalities. The initial mechanism of injury is the paralysis of the vital centers, which causes apnea, atrial fibrillation and cardiac arrest. In pregnant women, lightning can produce severe complications which depend on the point of entrance and its indirect effect on the fetus, affecting the cardiac conduction system and the central nervous system. We report a case of a lightning accident by direct strike on a 23-week pregnant woman, who's type of injury was by direct contact on the abdomen. She arrives to the emergency room with neurologic symptoms, maternal tachycardia and fetal bradycardia. The mother died due to myocardial infarction and the presence of an intracavitary embolus in the left ventricle, with the consequent maternal-fetal death. The incidence and injury mechanisms, as well as the clinical features and clinical management are described. MÉD.UIS.2019;32(1):21-6.


Assuntos
Humanos , Feminino , Gravidez , Adulto Jovem , Relâmpago , Morte Fetal , Morte Materna , Infarto do Miocárdio
20.
J Psychosom Res ; 120: 90-95, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30929714

RESUMO

INTRODUCTION: Lightning strike victims often suffer repercussions. Although a lightning strike constitutes a severe traumatic event, there is a lack of data about potential psychological sequelae. This is precisely the context in which we assessed the prevalence of Post-Traumatic Stress Disorder (PTSD) and Major Depressive Episode (MDE) in a group of lightning strike victims. METHODS: The symptoms of peritraumatic dissociation were evaluated on the basis of the Peritraumatic Dissociative Experiences Questionnaire (PDEQ) whilst the Peritraumatic Distress Inventory (PDI) was used to assess symptoms of distress. PTSD and MDE diagnoses were evaluated using the MINI (Mini International Neuropsychiatric Interview). Symptom intensity was assessed using the self-report PTSD Checklist-Specific (PCLS) and the Beck Depression Inventory II (BDI II), respectively. RESULTS: Forty-nine patients were enrolled in the study. As regards symptoms of depression, 28 patients (57.1%) reported a major depressive episode (MINI) including 10 (20.4%) of moderate intensity and 5 (10.2%) of severe intensity (BDI). In terms of PTSD symptoms, 13 patients (26.5%) reported probable PTSD (MINI) with a PCL-S score ≥ 45. A significant correlation was established between PDEQ and BDI II (Spearman correlation coefficient = 0.36, p = .012). A significant correlation was also found between PDI and PCLS (Spearman correlation coefficient = 0.43, p = .002). A further significant correlation was noted between PDEQ and PCLS (Spearman correlation coefficient = 0.31, p = .028). DISCUSSION: This study highlights the need for a multidisciplinary evaluation of lightning strike victims. Indeed, the prevalence of psychiatric disorders such as PTSD and MDE appears to be significant.


Assuntos
Depressão/diagnóstico , Depressão/epidemiologia , Relâmpago , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Adolescente , Adulto , Depressão/etiologia , Transtornos Dissociativos/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Escalas de Graduação Psiquiátrica , Transtornos de Estresse Pós-Traumáticos/etiologia , Inquéritos e Questionários , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...