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1.
Sci Total Environ ; 935: 173359, 2024 May 19.
Article in English | MEDLINE | ID: mdl-38768722

ABSTRACT

An in-depth analysis of the role of greenhouse gases (GHGs) in climate change is examined here along with their diverse sources, including the combustion of fossil fuels, agriculture, and industrial processes. Key GHG components such as carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) are considered, along with data on emissions across various economic sectors. The consequences of climate change are also highlighted, ranging from more frequent and intense extreme weather events to rising sea levels and impacts on ecosystems and human health. The industrial revolution and unrestricted use of fossil fuels are key factors leading to an increase in GHG concentrations in the atmosphere. Global efforts to reduce emissions are considered, starting with the 1997 Kyoto Protocol and culminating in the 2015 Paris Agreement. The limited effectiveness of early initiatives is underscored, emphasizing the significant importance of the Paris Agreement that provides a global framework for establishing goals to reduce GHG emissions by country. The Green Climate Fund and other international financial mechanisms are also considered as essential tools for financing sustainable projects in developing countries. The global community faces the challenge and necessity for more ambitious efforts to achieve the set goals for reducing GHG emissions. Successful strategies are examined by Sweden, Costa Rica, and Denmark to achieve zero GHG emissions that integrate renewable energy sources and technologies. The importance of global cooperation for creating a sustainable future is also emphasized.

2.
iScience ; 27(6): 109919, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38812551

ABSTRACT

The cerebral cortex is widely considered part of the neural substrate of consciousness, but direct causal evidence is missing. Here, we tested in mice whether optogenetic activation of cortical neurons in posterior parietal cortex (PtA) or medial prefrontal cortex (mPFC) is sufficient for arousal from three behavioral states characterized by progressively deeper unresponsiveness: sleep, a coma-like state induced by muscimol injection in the midbrain, and deep sevoflurane-dexmedetomidine anesthesia. We find that cortical stimulation always awakens the mice from both NREM sleep and REM sleep, with PtA requiring weaker/shorter light pulses than mPFC. Moreover, in most cases light pulses produce both cortical activation (decrease in low frequencies) and behavioral arousal (recovery of the righting reflex) from brainstem coma, as well as cortical activation from anesthesia. These findings provide evidence that direct activation of cortical neurons is sufficient for behavioral and/or cortical arousal from sleep, brainstem coma, and anesthesia.

3.
Circ Cardiovasc Imaging ; 17(2): e015712, 2024 02.
Article in English | MEDLINE | ID: mdl-38377241

ABSTRACT

BACKGROUND: Coronary artery calcium computed tomography (CAC) is an important tool for identifying subclinical atherosclerosis and cardiovascular risk stratification. Despite robust evidence and inclusion in current guidelines, CAC is considered investigational by some US insurance carriers and requires out-of-pocket expenses. CAC can be obtained via self-referral (SR) or physician referral (PR). We aimed to examine differences in patient, socioeconomic, and CAC characteristics between referral groups. METHODS: We evaluated demographic, medical history, and CAC results of consecutive patients with a CAC completed at one of multiple Wisconsin sites from March 1, 2019, to June 30, 2021. We separated patients into SR and PR groups. Through census data, we analyzed socioeconomic variables at the block level including race and ethnicity, median income, average household size, and high school completion in the areas where patients resided at the time of CAC. RESULTS: The final analysis included 19 726 patients: 13 835 (70.1%) PR and 5891 (29.9%) SR. Most patients in both groups were White (95.2% versus 95.1%), with the Black/African American population representing 2.7% (SR) and 2.3% (PR). The PR group had a higher prevalence of cardiovascular risk factors. SR patients were more likely to have a score of 0 (41.2% versus 38.1%; P<0.001); PR patients had a higher prevalence of CAC >300 (16.8% versus 14.8%; P<0.001). SR patients were more likely to be women (55.1% versus 48.9%; P<0.001) and were found to live in higher income areas (19.5% versus 16.4%; P<0.001). Patients from low-income areas comprised the smallest proportion in both groups (7.5%). CONCLUSIONS: Patients who obtain out-of-pocket CAC live predominantly in medium- and high-income areas, and patients from lower income locations are less likely to obtain CAC despite having more cardiovascular disease risk factors. Consideration should be made from a policy perspective to promote health equity and improve utilization of CAC testing among underrepresented groups.


Subject(s)
Coronary Artery Disease , Vascular Calcification , Humans , Female , Male , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/epidemiology , Calcium , Coronary Vessels/diagnostic imaging , Health Promotion , Risk Factors , Vascular Calcification/diagnostic imaging , Vascular Calcification/epidemiology , Risk Assessment
4.
Sci Rep ; 14(1): 4693, 2024 02 26.
Article in English | MEDLINE | ID: mdl-38409311

ABSTRACT

Deep ocean foraging northern elephant seals (Mirounga angustirostris) consume fish and squid in remote depths of the North Pacific Ocean. Contaminants bioaccumulated from prey are subsequently transferred by adult females to pups during gestation and lactation, linking pups to mercury contamination in mesopelagic food webs (200-1000 m depths). Maternal transfer of mercury to developing seal pups was related to maternal mercury contamination and was strongly correlated with maternal foraging behavior (biotelemetry and isotopes). Mercury concentrations in lanugo (hair grown in utero) were among the highest observed worldwide for young pinnipeds (geometric mean 23.01 µg/g dw, range 8.03-63.09 µg/g dw; n = 373); thus, some pups may be at an elevated risk of sub-lethal adverse health effects. Fetal mercury exposure was affected by maternal foraging geographic location and depth; mercury concentrations were highest in pups of the deepest diving, pelagic females. Moreover, pup lanugo mercury concentrations were strongly repeatable among successive pups of individual females, demonstrating relative consistency in pup mercury exposure based on maternal foraging strategies. Northern elephant seals are biosentinels of a remote deep-sea ecosystem. Our results suggest that mercury within North Pacific mesopelagic food webs may also pose an elevated risk to other mesopelagic-foraging predators and their offspring.


Subject(s)
Caniformia , Mercury , Seals, Earless , Animals , Female , Mercury/toxicity , Ecosystem , Pacific Ocean
6.
Methods Mol Biol ; 2710: 171-183, 2023.
Article in English | MEDLINE | ID: mdl-37688732

ABSTRACT

Spatial transcriptomics maps RNA molecules to the location in a tissue where they are expressed. Here we document the use of Slide-SeqV2 to visualize gene expression in the mouse olfactory bulb (OB). This approach relies on spatially identified beads to locate and quantify individual transcripts. The expression profiles associated with the beads are used to identify and localize individual cell types in an unbiased manner. We demonstrate the various cell types and subtypes with distinct spatial locations in the olfactory bulb that are identified using Slide-SeqV2.


Subject(s)
Gene Expression Profiling , Olfactory Bulb , Animals , Mice
7.
Sci Total Environ ; 898: 165569, 2023 Nov 10.
Article in English | MEDLINE | ID: mdl-37459985

ABSTRACT

Of the >17,943 thousand barrels per calendar day (bbl/d) of oil refining capacity located in the US, the Petroleum Administration for Defense District 3 (PADD-3) region has the largest number of refineries and accounts for >53 % (or 9607 tbbl/d) of all US oil refining capacity. Processing facilities in this area are mainly located on the Gulf of Mexico coast in Texas and Louisiana. This study selected a sub-region for analysis within the Mississippi River delta in the state of Louisiana between the cities of New Orleans and Baton Rouge. This region is characterized by intensive industrial activity connected with oil refining and related activities. The TROPOspheric Monitoring Instrument (TROPOMI) detected highly localized NO2 vertical column densities (VCDs) over the two largest US refineries in Baton Rouge (503,000 bbl/d) and Garyville (578,000 bbl/d). TROPOMI NO2 VCD over these stations were 100 µmol/m2 and 80 µmol/m2, respectively. A high correlation coefficient (r = 0.65, p < 0.05) was also found between TROPOMI NO2 and population density. Data from the National Emissions Inventory (NEI) showed high NOx emissions from refineries and other industries including coal-fired power generation, chemical, and aluminum processing plants. The results of the NO2 analysis are of practical interest for a comparative assessment of air pollution, as well as for the exchange of best practices in the field of low-waste fuel combustion technologies.

8.
J Fungi (Basel) ; 9(6)2023 Jun 01.
Article in English | MEDLINE | ID: mdl-37367577

ABSTRACT

BACKGROUND: Coccidioidomycosis (cocci) is an endemic fungal disease that can cause asymptomatic or post-symptomatic lung nodules which are visible on chest CT scanning. Lung nodules are common and can represent early lung cancer. Differentiating lung nodules due to cocci from those due to lung cancer can be difficult and lead to invasive and expensive evaluations. MATERIALS AND METHODS: We identified 302 patients with biopsy-proven cocci or bronchogenic carcinoma seen in our multidisciplinary nodule clinic. Two experienced radiologists who were blinded to the diagnosis read the chest CT scans and identified radiographic characteristics to determine their utility in differentiating lung cancer nodules from those due to cocci. RESULTS: Using univariate analysis, we identified several radiographic findings that differed between lung cancer and cocci infection. We then entered these variables along with age and gender into a multivariate model and found that age, nodule diameter, nodule cavitation, presence of satellite nodules and radiographic presence of chronic lung disease differed significantly between the two diagnoses. Three findings, cavitary nodules, satellite nodules and chronic lung disease, have sufficient discrimination to potentially be useful in clinical decision-making. CONCLUSIONS: Careful evaluation of the three obtained radiographic findings can significantly improve our ability to differentiate benign coccidioidomycosis infection from lung cancer in an endemic region for the fungal disease. Using these data may significantly reduce the cost and risk associated with distinguishing the cause of lung nodules in these patients by preventing unnecessary invasive studies.

9.
Animals (Basel) ; 13(5)2023 Feb 23.
Article in English | MEDLINE | ID: mdl-36899668

ABSTRACT

Turfgrass in equine sports has clear advantages over other types of reinforcement but adds complexity to the management. This study investigates factors that influence the turfgrass' surface performance and how the use of a drainage package and a geotextile reinforcement affect quantitative measurements of turfgrass. The measurements are made using affordable, lightweight testing tools that are readily available or easily constructed. Eight boxes with turfgrass over a mix of the arena with peat at a consistent depth were tested for volumetric moisture content (VMC %) with time-domain reflectometry (TDR), the rotational peak shear device (RPS), the impact test device (ITD), soil cone penetrometer (SCP), and the Going Stick (GS). Results obtained using TDR, RPS, ITD, SCP, and GS indicate that the presence of the geotextile and drainage package was mainly detected by VMC (%), SCP detected geotextile addition, and GS detected the interaction of geotextile × drainage package. Linear regression showed SCP and GS are related to geotextile and was positively correlated between them and negatively with VMC (%). The testing showed some limitations of these devices, mainly related to moisture content and sod composition, but the potential exists to utilize these devices for quality control as well as for the monitoring of maintenance of the surfaces when controlling the range of both VMC (%) and sod constitution.

10.
PLoS One ; 18(1): e0279623, 2023.
Article in English | MEDLINE | ID: mdl-36652422

ABSTRACT

Flow velocities within coral reefs are greatly reduced relative to those at the water surface. The in-reef flow controls key processes that flush heat, cycle nutrients and transport sediment from the reef to adjacent beaches, all key considerations in assessments of reef resilience and restoration interventions. An analytical framework is proposed and tested with a suite of high-resolution numerical experiments. We demonstrate a single parameter that describes the total coral frontal area explains variation of horizontally averaged velocity within a reef canopy across morphologies, densities, and flow depths. With the integration of existing data of coral cover and geometry, this framework is a practical step towards the prediction of near-bed flows in diverse reef environments.


Subject(s)
Anthozoa , Coral Reefs , Animals , Ecosystem
11.
Chest ; 163(5): 1214-1224, 2023 05.
Article in English | MEDLINE | ID: mdl-36336000

ABSTRACT

BACKGROUND: Although trust is central to successful physician-family relationships in ICUs, little is known about how to promote surrogates' trust of ICU physicians in this setting. RESEARCH QUESTION: Does the conduct of family conferences and physicians' use of shared decision-making (SDM) within family conferences impact surrogates' trust in the physician? STUDY DESIGN AND METHODS: A mixed-methods secondary analysis was done of a multicenter prospective cohort study of 369 surrogate decision-makers of 204 decisionally incapacitated patients at high risk of death or severe functional impairment within 13 ICUs at six US medical centers between 2008 and 2012. Surrogates completed the Abbreviated Wake Forest Physician Trust Scale (range, 5-25) before and after an audio-recorded family conference conducted within 5 days of ICU admission. We qualitatively coded transcribed conferences to determine physicians' use of five SDM behaviors: discussing surrogate's role, explaining medical condition and prognosis, providing emotional support, assessing understanding, and eliciting patient's values and preferences. Using multivariable linear regression with adjustment for clustering, we assessed whether surrogates' trust in the physician increased after the family meeting; we also examined whether the number of SDM behaviors used by physicians during the family meeting impacted trust scores. RESULTS: In adjusted models, conduct of a family meeting was associated with increased trust (average change, pre- to post family meeting: 0.91 point [95% CI, 0.4-1.4; P < .01]). Every additional element of SDM used during the family meeting, including discussing surrogate's role, providing emotional support, assessing understanding, and eliciting patient's values and preferences, was associated with a 0.37-point increase in trust (95% CI, 0.08-0.67; P = .01). If all four elements were used, trust increased by 1.48 points. Explaining medical condition or prognosis was observed in nearly every conference (98.5%) and was excluded from the final model. INTERPRETATION: The conduct of family meetings and physicians' use of SDM behaviors during meetings were both associated with increases in surrogates' trust in the treating physician.


Subject(s)
Physicians , Trust , Humans , Prospective Studies , Decision Making , Intensive Care Units , Physicians/psychology , Family
12.
Radiology ; 306(2): e213198, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36165790

ABSTRACT

Background A new modality, phase-sensitive breast tomosynthesis (PBT), may have similar diagnostic performance to conventional breast tomosynthesis but with a reduced radiation dose. Purpose To perform a pilot study of the performance of a novel PBT system compared with conventional digital breast tomosynthesis (DBT) in patients undergoing additional diagnostic imaging workup for breast lesions. Materials and Methods In a prospective study from June 2020 to March 2021, participants with suspicious breast lesions detected at screening DBT or MRI were recruited for additional PBT imaging before additional diagnostic workup or biopsy. In this pilot study, nine radiologists independently evaluated image quality and assessed the likelihood of lesion malignancy by retrospectively evaluating DBT and PBT images in two separate reading sessions. Image quality was rated subjectively using a Likert scale from 1 to 5. Areas under the receiver operating characteristic curve (AUCs) were used to compare the lesion classification (malignant vs benign) performance of the radiologists. Results Images in 50 patients (mean age, 56 years ± 12 [SD]; 49 women) with 52 evaluable lesions (28 malignant) were assessed. For image appearance and general feature visibility, DBT images had a higher total mean image quality score (3.8) than PBT images (2.9), with P < .002 for each comparison. For classification of lesions as benign or malignant, the AUCs were 0.74 for both PBT and DBT. PBT images were acquired at a 24% mean radiation dose reduction (mean, 1.78 mGy vs 2.34 mGy for DBT; P < .001). Conclusion The phase-sensitive breast tomosynthesis system had a 24% lower mean radiation dose compared with digital breast tomosynthesis, although with lower image quality. Diagnostic performance of the system remains to be determined in larger studies. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Gao and Moy in this issue.


Subject(s)
Breast Neoplasms , Breast , Female , Humans , Middle Aged , Pilot Projects , Prospective Studies , Retrospective Studies , Breast/diagnostic imaging , Mammography/methods , Breast Neoplasms/pathology
13.
J Digit Imaging ; 36(1): 365-372, 2023 02.
Article in English | MEDLINE | ID: mdl-36171520

ABSTRACT

We describe the curation, annotation methodology, and characteristics of the dataset used in an artificial intelligence challenge for detection and localization of COVID-19 on chest radiographs. The chest radiographs were annotated by an international group of radiologists into four mutually exclusive categories, including "typical," "indeterminate," and "atypical appearance" for COVID-19, or "negative for pneumonia," adapted from previously published guidelines, and bounding boxes were placed on airspace opacities. This dataset and respective annotations are available to researchers for academic and noncommercial use.


Subject(s)
COVID-19 , Humans , Artificial Intelligence , Radiography , Machine Learning , Radiologists , Radiography, Thoracic/methods
14.
Animals (Basel) ; 14(1)2023 Dec 21.
Article in English | MEDLINE | ID: mdl-38200768

ABSTRACT

Both pre-race meet and daily turf surface condition measurements are required by regulations adopted as part of the Horseracing Integrity and Safety Act (HISA). The Orono Biomechanical Surface Tester (OBST) is the primary device used for characterizing a racing surface and is used for the pre-meet inspections. Tools that are better suited for the daily testing of turf surfaces are also needed to meet the new federal regulations. The purpose of this study was to compare five simple tools commonly used in turf applications to the OBST. Data were collected with each of the six devices at plots chosen to approximate the current and potential compositions of North American turf racetracks. Correlations and linear regression models were then established between the simple tool measurements and the parameters measured by the OBST. The moisture probe was found to be the primary device for race day characterization due to its strong correlation to OBST measurements. The Longchamp Penetrometer is also prioritized for daily measurements due to its established correlation to horse performance and injuries. The Clegg Impact Hammer provides further improvement of the linear regression model. The Turf Shear Tester and GoingStick® were not found to correlate well to the biomechanically based device.

15.
Health Aff Sch ; 1(5): qxad053, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38756977

ABSTRACT

US health care administrative spending is approximately $1 trillion annually. A major operational area is the financial transactions ecosystem, which has approximately $200 billion in spending annually. Efficient financial transactions ecosystems from other industries and countries exhibit 2 features: immediate payment assurance and high use of automation throughout the process. The current system has an average transaction cost of $12 to $19 per claim across private payers and providers for more than 9 billion claims per year; each claim on average takes 4 to 6 weeks to process and pay. For simple claims, the transaction cost is $7 to $10 across private payers and providers; for complex claims, $35 to $40. Prior authorization on approximately 5000 codes has an average cost of $40 to $50 per submission for private payers and $20 to $30 for providers. Interventions aligned with a more efficient financial transactions ecosystem could reduce spending by $40 billion to $60 billion; approximately half is at the organizational level (scaling interventions being implemented by leading private payers and providers) and half at the industry level (adopting a centralized automated claims clearinghouse, standardizing medical policies for a subset of prior authorizations, and standardizing physician licensure for a national provider directory).

16.
Sci Adv ; 8(31): eabl8731, 2022 Aug 05.
Article in English | MEDLINE | ID: mdl-35921419

ABSTRACT

Occasionally, lightning will exit the top of a thunderstorm and connect to the lower edge of space, forming a gigantic jet. Here, we report on observations of a negative gigantic jet that transferred an extraordinary amount of charge between the troposphere and ionosphere (∼300 C). It occurred in unusual circumstances, emerging from an area of weak convection. As the discharge ascended from the cloud top, tens of very high frequency (VHF) radio sources were detected from 22 to 45 km altitude, while simultaneous optical emissions (777.4 nm OI emitted from lightning leaders) remained near cloud top (15 to 20 km altitude). This implies that the high-altitude VHF sources were produced by streamers and the streamer discharge activity can extend all the way from near cloud top to the ionosphere. The simultaneous three-dimensional radio and optical data indicate that VHF lightning networks detect emissions from streamer corona rather than the leader channel, which has broad implications to lightning physics beyond that of gigantic jets.

17.
Sci Total Environ ; 849: 157827, 2022 Nov 25.
Article in English | MEDLINE | ID: mdl-35944626

ABSTRACT

The eruption of the Cumbre Vieja volcano on the island of La Palma (Canary Islands, Spain) began on September 19, 2021 and ended on December 13, 2021. It lasted continuously for 85 days with short periods of calm when lava did not exit the cone of the volcano. Vast amounts of volcanic material, including ash and gases, were emitted into the environment. This research focuses on these emissions. The main objective is to use available open-source data to examine the impact on regional and local air quality. Data from the following sources were used: 1) Copernicus Atmosphere Monitoring Service (CAMS) data was used to track the transfer of volcanic SO2 in the troposphere in early October over long distances from the source of the eruption, including Western and Eastern Europe, across the Atlantic Ocean and the Caribbean; 2) Data from ground monitoring stations measured the concentrations of SO2 and PM10 near the source; 3) AErosol RObotic NETwork (AERONET) data from the La Palma station that showed high Aerosol Optical Depth (AOD) values (over 0.4) during the active phase of emissions on September 24 and 28, as well as on October 3; 4) Ångström Exponent (AE) values indicated the presence of particles of different sizes. On September 24, high AE values (>1.5), showed the presence of fine-mode fraction scattering aerosols such as sulfates; 5) Cloud Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) data additionally confirmed the presence of sulfate and dust aerosols in the atmosphere over the region. However, the influence of Saharan dust on the atmosphere of the entire region could not be excluded. This research helps forecast air pollution resulting from large-scale volcanic eruptions and associated health risks to humans.


Subject(s)
Air Pollutants , Air Pollution , Aerosols/analysis , Air Pollutants/analysis , Air Pollution/analysis , Dust/analysis , Environmental Monitoring/methods , Gases , Humans , Spain , Sulfates , Volcanic Eruptions
18.
Cureus ; 14(6): e25603, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35795518

ABSTRACT

Caffeine is the world's most widely used psychoactive legal substance. The involvement of caffeine in pain management has gotten minimal attention in the past, but it is getting more attention now. This article provides a brief assessment of the literature to clarify the role of caffeine as a pain reliever and stimulate the interest of researchers. Caffeine affects adenosine receptors, which are involved in nociception, and plays a significant role in pain regulation. Caffeine's usage as an adjuvant therapy has been extensively documented in the literature, and it is now accessible in certain over-the-counter drugs. The mixture of coffee and morphine for pain reduction in individuals with terminal cancer has shown mixed outcomes in studies. Caffeine can be utilized for hypnic headaches and post-dural puncture headaches since it is crucial in pain regulation. Caffeine has the potential to help in pain management. Caffeine's usage for migraines and end-stage cancer disease is not well acknowledged. Further research is essential to focus on caffeine's potential role in various forms of pain, including dosage escalation and outcome assessment standardization.

19.
Earth Space Sci ; 9(1): e2021EA001943, 2022 Jan.
Article in English | MEDLINE | ID: mdl-35865260

ABSTRACT

Lightning is measured from space using optical instruments that detect transient changes in the illumination of the cloud top. How much of the flash (if any) is recorded by the instrument depends on the instrument detection threshold. NOAA's Geostationary Lightning Mapper (GLM) employs a dynamic threshold that varies across the imaging array and changes over time. This causes flashes in certain regions and at night to be recorded in greater detail than other flashes, and threshold inconsistencies will impose biases on all levels of GLM data products. In this study, we quantify the impact of the varying GLM threshold on event/group/flash detection, flash clustering, and gridded product generation by imposing artificial thresholds on the event data taken from a thunderstorm with a low instrument threshold (∼0.7 fJ). We find that even modest increases in threshold severely impact event (60% loss by 2 fJ, 90% loss by 10 fJ) and group (25% loss by 2 fJ, 81% loss by 10 fJ) detection by suppressing faint illumination of the cloud top from weak sources and scattering. Flash detection is impacted less by threshold increases (4% loss by 2 fJ), but reductions are still significant at higher thresholds (35% loss by 10 fJ, or 44% if single-group flashes are removed). Undetected pulses cause individual flashes to be split and severely impact the construction of gridded products. All of these factors complicate the interpretation of GLM data, particularly when trended over time under a changing threshold.

20.
Earth Space Sci ; 9(1): e2021EA001944, 2022 Jan.
Article in English | MEDLINE | ID: mdl-35865262

ABSTRACT

Optical space-based lightning sensors such as the Geostationary Lightning Mapper (GLM) detect and geolocate lightning by recording rapid changes in cloud top illumination. While lightning locations can be determined to within a pixel on the GLM imaging array, these instruments are not individually able to natively report lightning altitude. It has previously been shown that thunderclouds are illuminated differently based on the altitude of the optical source. In this study, we examine how altitude information can be extracted from the spatial distributions of GLM energy recorded from each optical pulse. We match GLM "groups" with Lightning Mapping Array (LMA) source data that accurately report the 3-D positions of coincident Radio-Frequency (RF) emitters. We then use machine learning methods to predict the mean LMA source altitudes matched to GLM groups using metrics from the optical data that describe the amplitude, breadth, and texture of the group spatial energy distribution. The resulting model can predict the LMA mean source altitude from GLM group data with a median absolute error of <1.5 km, which is sufficient to determine the location of the charge layer where the optical energy originated. This model is able to capture changes to the source altitude distribution in response to convective processes in the thunderstorm, and the GLM predictions can reveal the vertical structure of individual flashes - enabling 3-D flash geolocation with GLM for the first time. Future work will account for differences in thunderstorm charge/precipitation structures and viewing angle across the GLM Field of View.

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