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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.

3.
Sci Rep ; 14(1): 8083, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582762

RESUMO

X-rays have been observed in natural downward cloud-to-ground lightning for over 20 years and in rocket-triggered lightning for slightly less. In both cases, this energetic radiation has been detected during the stepped and dart leader phases of downward negative flashes. More recently, X-rays have also been reported during the dart leader phase of upward negative flashes. In this study, we present the observations of four upward positive lightning flashes from the Säntis Tower (2.5 km ASL) in Switzerland. These consist of the simultaneous records of electric current passing through the tower, and electric field strength and X-ray flux 20 m from the tower base. One of the flashes was captured by a high-speed camera operating at 24,000 frames per second, stills from which are also presented. We detected X-rays during the initial phase of upward negative leader propagation, which can be associated with the leader-stepping process from electric field and current waveforms. To the best of our knowledge, this is the first time that such measurements are reported in the literature. The obtained time-synchronised data confirm that the X-ray emissions detected are associated with the initial steps of the upward negative leader. The frequency and energy of X-ray pulses appear to decrease as functions of time, with pulses disappearing altogether within the first millisecond of the leader initiation. X-ray emission also appears to be correlated with the maximum current-derivative and the electric field change of leader steps, consistent with cold electron runaway. These observations contribute to improving our understanding of upward lightning, which is a primary source of damage to tall structures such as wind turbines and telecommunications towers, as well as aircraft during takeoff and landing.

4.
Sci Total Environ ; : 172329, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38608892

RESUMO

As insect populations decline in many regions, conservation biologists are increasingly tasked with identifying factors that threaten insect species and developing effective strategies for their conservation. One insect group of global conservation concern are fireflies (Coleoptera: Lampyridae). Although quantitative data on firefly populations are lacking for most species, anecdotal reports suggest that some firefly populations have declined in recent decades. Researchers have hypothesized that North American firefly populations are most threatened by habitat loss, pesticide use, and light pollution, but the importance of these factors in shaping firefly populations has not been rigorously examined at broad spatial scales. Using data from >24,000 surveys (spanning 2008-16) from the citizen science program Firefly Watch, we trained machine learning models to evaluate the relative importance of a variety of factors on bioluminescent firefly populations: pesticides, artificial lights at night, land cover, soil/topography, short-term weather, and long-term climate. Our analyses revealed that firefly abundance was driven by complex interactions among soil conditions (e.g., percent sand composition), climate/weather (e.g., growing degree days), and land cover characteristics (e.g., percent agriculture and impervious cover). Given the significant impact that climactic and weather conditions have on firefly abundance, there is a strong likelihood that firefly populations will be influenced by climate change, with some regions becoming higher quality and supporting larger firefly populations, and others potentially losing populations altogether. Collectively, our results support hypotheses related to factors threatening firefly populations, especially habitat loss, and suggest that climate change may pose a greater threat than appreciated in previous assessments. Thus, future conservation of North American firefly populations will depend upon 1) consistent and continued monitoring of populations via programs like Firefly Watch, 2) efforts to mitigate the impacts of climate change, and 3) insect-friendly conservation practices.

5.
Heliyon ; 10(7): e28708, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38586337

RESUMO

Bangladesh has witnessed alarmingly rising lightning frequency, particularly during pre-monsoon and monsoon seasons. This has resulted in significant annual death tolls from lightning strikes over the past decade. Recognizing this crisis, the country officially declared lightning casualties a natural disaster in 2016. This study delves deeper into the landscape of lightning fatalities and causalities in Bangladesh. Utilizing secondary data sources, this research introduces a unique approach by integrating Bangladesh Meteorological Department (BMD) data and NASA's Lightning Imaging Sensor (LIS) data from the International Space Station's (ISS) Near-real Time (NRT) mission. This combined dataset allows for a more comprehensive analysis. Furthermore, Geographic Information Systems (GIS) was employed to analyze spatial distributions and generate maps. The Inverse Distance Weighted (IDW) interpolation tool was used to create detailed spatial distribution maps of lightning fatalities, thunderstorm days (TSDs), and lightning flash frequency (LFF) across Bangladesh. The analysis revealed that farmers and fishermen were the most vulnerable populations, with the northeastern regions experiencing the highest impact. Sylhet division emerged as the area with the most fatalities, highlighting the northeastern zone's susceptibility. The study also identified monsoons as the period with the highest occurrences of lightning deaths and injuries. By combining innovative data integration and spatial analysis, this study offers valuable insights into the alarming trend of lightning fatalities in Bangladesh. These findings can inform targeted prevention strategies and interventions to safeguard vulnerable populations and communities.

6.
J Geophys Res Atmos ; 129(1): e2023JD039505, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38440118

RESUMO

Upward lightning (UL) has become a major threat to the growing number of wind turbines producing renewable electricity. It can be much more destructive than downward lightning due to the large charge transfer involved in the discharge process. Ground-truth lightning current measurements indicate that less than 50% of UL could be detected by lightning location systems (LLS). UL is expected to be the dominant lightning type during the cold season. However, current standards for assessing the risk of lightning at wind turbines mainly consider summer lightning, which is derived from LLS. This study assesses the risk of LLS-detectable and LLS-undetectable UL at wind turbines using direct UL measurements at instrumented towers. These are linked to meteorological data using random forests. The meteorological drivers for the absence/occurrence of UL are found from these models. In a second step, the results of the tower-trained models are extended to a larger study area (central and northern Germany). The tower-trained models for LLS-detectable lightning are independently verified at wind turbine sites in this area and found to reliably diagnose this type of UL. Risk maps based on cold season case study events show that high probabilities in the study area coincide with actual UL flashes. This lends credibility to the application of the model to all UL types, increasing both risk and affected areas.

7.
Proc Natl Acad Sci U S A ; 121(7): e2309131121, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38315852

RESUMO

Most of the nitrogen (N) accessible for life is trapped in dinitrogen (N2), the most stable atmospheric molecule. In order to be metabolized by living organisms, N2 has to be converted into biologically assimilable forms, so-called fixed N. Nowadays, nearly all the N-fixation is achieved through biological and anthropogenic processes. However, in early prebiotic environments of the Earth, N-fixation must have occurred via natural abiotic processes. One of the most invoked processes is electrical discharges, including from thunderstorms and lightning associated with volcanic eruptions. Despite the frequent occurrence of volcanic lightning during explosive eruptions and convincing laboratory experimentation, no evidence of substantial N-fixation has been found in any geological archive. Here, we report on the discovery of a significant amount of nitrate in volcanic deposits from Neogene caldera-forming eruptions, which are well correlated with the concentrations of species directly emitted by volcanoes (sulfur, chlorine). The multi-isotopic composition (δ18O, Δ17O) of the nitrates reveals that they originate from the atmospheric oxidation of nitrogen oxides formed by volcanic lightning. According to these first geological volcanic nitrate archive, we estimate that, on average, about 60 Tg of N can be fixed during a large explosive event. Our findings hint at a unique role potentially played by subaerial explosive eruptions in supplying essential ingredients for the emergence of life on Earth.

8.
Heliyon ; 10(4): e26390, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38420396

RESUMO

This work aimed to evaluate the growth of two species of microgreens (mizuna and pak choi), using agro-industrial compost as growing media in two different mixes versus one hundred percent peat, under two different LED illumination spectra (LED 1 and LED 2) in a 14 h photoperiod. The experiment was carried-out for two times. Biomass yield, glucosinolates, and phenolic compounds, and nitrate (NO3-) content were analysed in leaf tissues. In both species, the highest fresh and dry biomass production was in compost:peat (50:50%) and LED 2 (Blue/Red/Far Red). In general, compost had a greater influence on nitrate content than light, but in the microgreen pak choi, the anthocyanin content was inhibited by the compost treatment. In the other hand both LED illumination had a positive effect on mizuna for glucosinolates and anthocyanins, and LED 2 also showed a positive effect on pak choi for anthocyanin. Therefore, the use of agri-food compost: peat (50:50%) with LED 2 (blue/red) lighting treatment to obtain microgreens in indoor crops is a plausible technology that provides nutritionally and phytochemically rich crops.

9.
Sci Rep ; 14(1): 3862, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38366004

RESUMO

There is little consensus among global climate models (CGMs) regarding the response of lightning flash rates to past and future climate change, largely due to graupel not being included in models. Here a two-moment prognostic graupel scheme was incorporated into the MIROC6 GCM and applied in three experiments involving pre-industrial aerosol, present-day, and future warming simulations. The new microphysics scheme performed well in reproducing global distributions of graupel, convective available potential energy, and lightning flash rate against satellite retrievals and reanalysis datasets. The global mean lightning rate increased by 7.1% from the pre-industrial period to the present day, which was attributed to increased graupel occurrence. The impact of future warming on lightning activity was more evident, with the rate increasing by 18.4[Formula: see text] through synergistic contributions of destabilization and increased graupel. In the Arctic, the lightning rate depends strongly on the seasonality of graupel, emphasizing the need to incorporate graupel into GCMs for more accurate climate prediction.

11.
Explore (NY) ; 20(2): 248-252, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38176975

RESUMO

As a result of the COVID-19 pandemic, Long COVID (LC) is now prevalent in many countries. Little evidence exists regarding how this chronic condition should be treated, but guidelines suggest for most people it can be managed symptomatically in primary care. The Lightning Process is a trademarked positive psychology focused self-management programme which has shown to be effective in reducing fatigue and accompanying symptoms in other chronic conditions including Chronic Fatigue Syndrome/Myalgic Encephalomyelitis. Here we outline its novel application to two patients with LC who both reported improvements in fatigue and a range of physical and emotional symptoms post-treatment and at 3 months follow-up.


Assuntos
COVID-19 , Síndrome de Fadiga Crônica , Humanos , Síndrome Pós-COVID-19 Aguda , Pandemias , COVID-19/terapia , Síndrome de Fadiga Crônica/terapia , Síndrome de Fadiga Crônica/diagnóstico , Síndrome de Fadiga Crônica/psicologia , Atenção Primária à Saúde
12.
Sci Total Environ ; 915: 169947, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38220021

RESUMO

Association of lightning with Lifting Condensation Level (LCL), Equilibrium Level (EL), K Index, and humidity at 850 mb and 200 mb in 2019 and 2020 over National Capital Region (Delhi) (Lat: 27°N -29°N, Lon: 76°E-78°E) is investigated using in-situ observation data. Study shows high lightning activity during low LCL, and vice versa. This high lighting and low LCL is associated with high relative humidity at 850 mb, and high "K" index. Low LCL and high relative humidity (low dew point depression) at 850 mb helps in generating super cell thunderstorms with spinning/tornado updraft. It is seen that asymmetric LCL height and relative humidity at 850 mb is the prime causes for uneven seasonal lightning in 2019 and 2020 over the region, despite more or less same seasonal aerosol and relative humidity. Anvil clouds behave uneven with time, despite, unanimous cloud top glaciation.

13.
Phys Med ; 117: 103202, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38159546

RESUMO

PURPOSE: Stereotactic radiosurgery with linear accelerators (LINACs) or Leksell Gamma Knife® (LGK, Elekta AB) is an established treatment option for intracranial tumors. When those are involving/abutting organs at risk (OAR), homogenous and normofractionated treatments outmatch single fraction deliveries. In such situations, it would be desirable to balance LINAC's homogeneity benefits with LGK's dose gradient attributes. In this study, we determined homogeneity and OAR sparing ranges using a non-clinical, homogenous prototype version of LGK Lightning. METHODS: We retrospectively analyzed thirty fractionated LGK Icon in-house patients with acoustic neuromas, pituitary adenomas and meningiomas. Four treatment plans were generated (54 Gy,1.8 Gy/fx) per patient: one LINAC plan, one clinical Lightning plan ("LGK") and two prototype Lightning plans ("LGK Hom" and "LGK OAR"). We analyzed Dmean and D2% for different OAR, Gradient Index (GI), Paddick Conformity Index (PCI), Homogeneity Index (HI) and beam-on-time (BOT). RESULTS: While the LINAC vs. Lightning plans (LGK Hom|LGK OAR|LGK) boast better homogeneity (median: 1.08 vs. 1.18|1.24|1.35) and shorter BOT (median: 137 s vs. 432 s|510 s|510 s), Lightning plans show improved GI (median: 6.68 vs. 3.86|3.50|3.19), similar PCI (median: 0.75 vs. 0.76|0.75|0.82) and significantly reduced OAR doses. For in-tumor OAR, LGK Hom and LINAC plans achieves similar OAR sparing with improved GI for LGK Hom. CONCLUSIONS: This study is a preliminary attempt to combine the dosimetric advantages of LINAC and LGK treatment planning. We observed that LGK plan homogeneity can be improved toward LINAC standards while maintaining the LGK advantage of favorable OAR doses and GI. Additionally, in-tumor OAR hotspots can be considerably reduced.


Assuntos
Neoplasias Encefálicas , Neoplasias Meníngeas , Radiocirurgia , Radioterapia de Intensidade Modulada , Humanos , Estudos Retrospectivos , Neoplasias Encefálicas/patologia , Aceleradores de Partículas , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Neoplasias Meníngeas/cirurgia
14.
Sensors (Basel) ; 23(24)2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38139615

RESUMO

Large-scale incorporation of new energy generation units based on renewable sources, such as wind and photovoltaic power, drastically alters the structure of the power system. Because of the intermittent nature of these sources, switching in grids (connection and disconnection) occurs much more frequently than with conventional sources. As a result, the power system will inevitably experience a large number of transients, which raises questions about the stability of the system and the quality of the electrical energy. Therefore, measuring various types of transients in power system is crucial for stability, power quality, fault analysis, protection design, and insulation design. Transient recorders that are currently used are generally expensive and only suitable for particular locations in power systems. The number of installed transient recorders is insufficient for a comprehensive analysis of problems that may occur. Hence, it is important to have inexpensive and efficient transient recorders that can be installed at multiple points in the power system on various types of objects. It is also essential to have a transient record database with open access, which can be used by researchers to develop new analysis techniques based on artificial intelligence. This paper proposes an inexpensive measurement and acquisition system designed to record transient phenomena on different objects within the power system. The system is designed to use autonomous power, a standardized data acquisition module, a low-budget system for transmitting recorded transient events to the server via mobile network, and a sensor system adapted to the object where transients are recorded. The proposed system is designed to be used for all types of objects in the power system where transients may occur, such as power lines, transmission towers, surge arresters, and transformers. All components of the system are described, and the system is tested under laboratory conditions. The modular nature of the system allows customization to the specifics of the location in power system by choosing appropriate components. The calibration method of the custom designed Rogowski coil is described. The cost analysis of the proposed system and power consumption analysis are performed. The results show that the system's performance meets application requirements at a low cost.

15.
Cureus ; 15(11): e49096, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38125222

RESUMO

Lightning is a common atmospheric occurrence. However, lightning strikes are not a frequent environmental cause of human injury. Survivors may present with Lichtenberg figures, a fern-like skin manifestation, and burns of varying severity. After a lightning strike, our patient demonstrated atypical cutaneous manifestations of large, ecchymotic discolorations on the medial upper extremities. After a comprehensive evaluation, the patient fully recovered and was discharged home without limitations. This case highlights lightning strike injury, including common findings, epidemiology, mechanisms, and prevention.

16.
Burns ; 2023 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-37945505

RESUMO

INTRODUCTION: Electrical injuries can be devastating, and data is lacking in low-resource settings. We aimed to identify predictors of mortality following electrical and lightning injuries (ELI) in Malawi. METHODS: We performed a retrospective observational study of patients presenting with ELI and burn injuries at a tertiary hospital in Malawi from 2011 to 2020. Outcomes were compared and predictors of mortality were modeled. RESULTS: A total of 382 ELI and 6371 burn patients were included. The mean ages for ELI and burn groups were 24 ± 14 and 11 ± 14 years, respectively (p < 0.01). Most patients were injured at home (91% in the burn group versus 51% in the ELI group, p < 0.01). The crude mortality rate in the ELI group was 28%, compared to 12% in the burn group (p < 0.01). On multivariate logistic regression, predictors of mortality included ELI (odds ratio [OR] 13.3, 95% confidence interval [CI] 7.2-24.5) and total body surface area burned (OR 1.1, 95% CI 1.1-1.1). Predicted mortality for ELI has increased over time (p = 0.05). CONCLUSIONS: ELI confers more than 13 times higher odds of mortality than burn injuries in Malawi, with mortality risk increasing over time. More efforts are needed to prevent electrical hazards and implement timely interventions for patients with ELI.

17.
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.

18.
Clim Dyn ; 61(9-10): 4125-4137, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37854482

RESUMO

The response of lightning to a changing climate is not fully understood. Historic trends of proxies known for fostering convective environments suggest an increase of lightning over large parts of Europe. Since lightning results from the interaction of processes on many scales, as many of these processes as possible must be considered for a comprehensive answer. Recent achievements of decade-long seamless lightning measurements and hourly reanalyses of atmospheric conditions including cloud micro-physics combined with flexible regression techniques have made a reliable reconstruction of cloud-to-ground lightning down to its seasonally varying diurnal cycle feasible. The European Eastern Alps and their surroundings are chosen as reconstruction region since this domain includes a large variety of land-cover, topographical and atmospheric circulation conditions. The most intense changes over the four decades from 1980 to 2019 occurred over the high Alps where lightning activity doubled in the 2010 s compared to the 1980 s. There, the lightning season reaches a higher maximum and starts one month earlier. Diurnally, the peak is up to 50% stronger with more lightning strikes in the afternoon and evening hours. Signals along the southern and northern alpine rim are similar but weaker whereas the flatlands surrounding the Alps have no significant trend.

20.
Sensors (Basel) ; 23(17)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37687923

RESUMO

Lightning strikes are the main cause of transmission line faults, and the accurate lightning current number is an important basis to guide scientific lightning protection. The use of sensors with excellent sensing performance to carry out lightning current monitoring on transmission lines is beneficial to the accumulation of key parameters of original lightning strikes, so it is necessary to study the lightning current measurement structure of transmission lines. In this paper, an optical current-sensing unit is used to monitor the lightning current on transmission lines. A measuring structure that can monitor key parameters of the lightning current under different types of lightning strikes is proposed. First, establish the lightning current return channel model and the equivalent model of the tower, study the influence of the transmission tower on the current in the lightning channel, and analyze the direct measurement position of the lightning current on the tower; establish the multi-wave impedance model of the tower, and build a multi-base tower. The simulation model of the transmission system analyzes the transmission characteristics of the lightning current on the transmission line and the lightning protection line in the case of different types of faults; from the perspective of the measurement of key parameters of the lightning current, the lightning current measurement structure of the transmission system is constructed to analyze different lightning strikes. The measurement effect of each monitoring position in the case of a lightning strike and the waveform characteristics of the fault current in the case of insulator flashover are analyzed.

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