Intentional Exposure Research Articles

B-327 Evidence of Missed Novel Psychoactive Substances (NPS) in Unexpected Fentanyl Positives

Abstract Background Recent data published by the CDC indicated that overdose deaths in the United States began to increase significantly in 2020 and continued throughout 2021. Synthetic opioids, such as illicitly-manufactured fentanyl (IMF), have been a primary driver in overdose deaths. There has been a concomitant increase in both the prevalence and diversification of novel psychoactive substances (NPS) and IMF. We performed a blinded secondary analysis of remnant samples to further characterize the incidence in which individuals are encountering NPS when using non-prescribed fentanyl. Various classes of NPS compounds (e.g., designer opioids, designer benzodiazepines, xylazine) were evaluated in samples that were originally positive for fentanyl but did not include a request from the provider for NPS testing to be performed. Methods This study was IRB approved. A sampling of 200 urine or oral fluid specimens collected from individuals as part of their routine medical treatment, wherein definitive testing for fentanyl and norfentanyl was performed and the drug and metabolite were both identified above the upper limit of quantitation of the assay, underwent additional analysis for NPS. Samples were excluded from blinded secondary analysis if any NPS testing, regardless of drug class, was originally ordered and performed. Additional testing that was performed included the following classes of drugs: designer opioids, designer benzodiazepines, synthetic cannabinoids, synthetic stimulants, hallucinogens/dissociatives, xylazine, tianeptine, and phenibut. Results Specimens within the sample set (N: 200) that were originally positive for fentanyl without a previous request for NPS testing originated from 30 different states within the US. These samples were originally collected between 9/19/2022–1/12/2023. Of those that underwent additional analysis after initial reporting of positive fentanyl results, 117 (58.5%) had at least one analyte within an NPS class identified. Designer opioids (N: 93, 47%), and xylazine (N: 76, 38%), followed by designer benzodiazepines (N: 16, 8%), synthetic stimulants (N: 4, 2%), and hallucinogens/dissociatives (N:3, 2%) were the most frequent compounds detected on a per sample basis. No synthetic cannabinoids were detected within this sample set. Conclusion Although much of the national focus around fatal and non-fatal overdoses centers on intentional and unintentional exposures to IMF, healthcare providers and the general public must be made aware of the prevalence of NPS. These compounds, which are often intentionally added to drugs sold as fentanyl to enhance the drug potency, can increase risk for an adverse event. Of paramount importance is that the effects of substances such as xylazine and designer benzodiazepines, which contribute to central nervous system depression, are not effectively reversed by administration of naloxone, a mainstay of harm reduction protocols. Knowledge of the prevalence of these compounds should impact clinical decision-making and individual risk mitigation plans. From a broader perspective, improving understanding of the incidence in which these drugs are found within communities could improve overall surveillance efforts on current drug use trends.

Financial Resource Management Knowledge, Skills, and Attitudes for Entry-level Physical Therapist Practice: A Survey of Physical Therapists in Ohio.

The purpose of this study was to explore the perceptions of physical therapists (PTs) regarding the importance of financial resource management (FRM) knowledge, skills, and attitudes (KSAs) for entry-level practice and investigate the roles of PT education programs (PTEPs), clinical education experiences (CEEs), and employers in addressing these KSAs. FRM KSAs have been identified as components of professionalism and leadership and, as such, are a required element in student PTs (SPTs) educational preparation. A purposive sampling of convenience strategy was employed by requesting a free mailing list for Ohio-licensed PTs. An online survey was developed based on PT Clinical Performance Instrument Criterion #17, "Patient Management: Financial Resources," as this tool is frequently used to endorse entry-level status of SPTs. Potential participants were solicited through email. Mixed methodology was used to analyze survey results. The survey was completed by 266 PTs. FRM KSAs in legal and regulatory compliance were perceived as most important, followed by coding and billing. Forty-eight percent of participants indicated that FRM KSAs were "less important" (n = 111) or "considerably less important" (n = 17) than clinical care skills, whereas 39.8% (n = 106) believed that these skills are of the same level of importance. Ten themes were derived from qualitative responses regarding the FRM content that should be provided by PTEPs. Participants indicated that the role of PTEPs was to provide an introduction and foundation to FRM, whereas CEEs should facilitate intentional exposure and opportunities to apply FRM KSAs with supervision. Employers were expected to provide education regarding clinic-specific operations and reimbursement considerations, as well as mentorship that included reviewing complex billing for accuracy, offering guidance for improving time management skills, and discussing fiscal responsibilities to both the employer and patient. This information may guide PTEPs and clinical personnel in providing focused meaningful instruction regarding FRM aspects of PT practice to SPTs and entry-level clinicians.

Rapid and simple identification of trace amounts of sodium azide in beverages and bodily fluids followed by derivatization and liquid chromatography-electrospray ionization tandem mass spectrometry.

Sodium azide (NaN3 ) is a toxic chemical agent to humans by ingestion and inhalation with a growing number of intentional exposures and accidental cases over the last few decades. Due to its low molecular weight and lack of any chromophore, its retention and detection by reverse-phase liquid chromatography-ultraviolet-mass spectrometry methods are a challenging task. To be able to confirm azide exposure, we have developed a method to identify azide in both beverages and bodily fluids. The identification of azide (N3 - ) is based on derivatization with N-(2-(bromomethyl)benzyl)-N,N-diethylethanaminium bromide (CAX-B) at 25°C for 15 min followed by LC/ESI-MS/MS analysis, with no other sample preparation. The azide after derivatization (CAX-N3 ) was stable, retainable by LC and sensitively detected by selected reaction monitoring. The ESI-MS/MS fragmentation of the M+ precursor ion produced characteristic product ions at m/z 118, 100, 91 and 86. The calibration curves for CAX-N3 showed linearity over two orders of magnitude with R2 value of 0.99. Low limits of identification of 0.1-0.5ng/mL were obtained in all investigated matrices (drinking water, tea, orange juice, plasma and urine). Compared with previously reported chromatography-based methods, this method that was based on derivatization and LC/ESI-MS/MS analysis was substantially more sensitive, simpler and faster. The method can be used for forensic investigation to confirm azide exposure from fatal use to much smaller intoxication dose.

ENHANCING VOCABULARY LEARNING IN ELEMENTARY LANGUAGE EDUCATION: EXPLORING EFFECTIVE STRATEGIES AND INTERACTIVE APPROACHES

This study delves into the instructional strategies employed by elementary language teachers for vocabulary teaching. Through in-depth interviews with five experienced educators, their approaches, challenges, and insights concerning vocabulary development were closely examined. The findings underscore the pivotal role of intentional and continuous word exposure in effective vocabulary instruction. The study identifies various strategies encompassing captivating games, collaborative group activities, visual aids such as graphic organizers, images, and labels, alongside consistent repetition of word sets. These techniques collectively bolster reading comprehension, writing proficiency, and oral communication skills among young learners. The research underscores the significance of cultivating dynamic and interactive learning settings that facilitate meaningful and consistent encounters with new vocabulary. The insights gleaned from this investigation contribute to the ongoing endeavor of refining vocabulary instruction methods, with the ultimate aim of fostering academic achievement and language progression in students. The study advocates for further exploration and application of these strategies to fully harness the benefits of vocabulary exposure in language teaching and learning. KEY IDEAS – strategies; vocabulary instruction; vocabulary development; learning environment; language instruction

Lycium barbarum polysaccharide-glycoprotein ameliorates ionizing radiation-induced epithelial injury by regulating oxidative stress and ferroptosis via the Nrf2 pathway.

Radiation-induced oral mucositis (RIOM) is considered to be the most common acute side effect of radiation therapy and occurs during intentional or accidental radiation exposure. Antioxidant synthesis agents have been reported to protect against or alleviate the development of mucositis, but the resulting side effects of chemical synthesis agents limit their use in clinical practice. Lycium barbarum polysaccharide-glycoprotein (LBP), a polysaccharide extract of the Lycium barbarum fruit, has superior antioxidant capacity and biosafety and is a potential option for radiation prevention and treatment. Here, we aimed to investigate whether LBP conferred radioprotection against ionizing radiation-induced oral mucosal damage. We found that LBP exerted radioprotective effects in irradiated HaCaT cells, improving cell viability, stabilizing mitochondrial membrane potential, and decreasing cell death. LBP pretreatment reduced oxidative stress and ferroptosis in radioactivity-damaged cells by activating the transcription factor Nrf2 and promoting its downstream targets, such as HO-1, NQO1, SLC7A11, and FTH1. Knockdown of Nrf2 eliminated the protective effects of LBP, implying the essential role of Nrf2 in LBP activity. Additionally, the topical application of LBP thermosensitive hydrogel on rat mucosa resulted in a significant decrease in ulcer size in the irradiated group, suggesting that LBP oral mucoadhesive gel may be a potential tool for the treatment of irradiation. In conclusion, we demonstrated that LBP attenuates ionizing radiation-induced oral mucosa injury by reducing oxidative stress and inhibiting ferroptosis via the Nrf2 signaling pathway. LBP may be a promising medical countermeasure against RIOM.

Self-poisoning by E-cigarette and E-liquids: National Reports to French Poison Control Centers from July 2019 to December 2020: VIGIlance and VAPE: The VIGIVAPE Study.

Exposure to e-cigarette liquids, whether intentional or accidental, might lead to adverse events. This study aimed to describe the prevalence and characteristics of exposures to e-liquids reported to French Poison Control Centers. All e-liquids exposure cases reported to French Poison Control Centers from July 1, 2019, to December 31, 2020, were reviewed. Information was collected about the patient's characteristics, exposure circumstances, management and outcome. About 919 cases of exposure to e-liquids were reported. Ages ranged from one month to 89 years, with a mean age of 16.6 ± 18.6 years and a median age of 4 years. The highest number of exposures-50.7%-concerned infants (0-4 years), 3.1% children (5-11 years), 5.9% adolescents (12-17 years), and 40.1% of cases concerned adults. The majority of cases were accidental (95.0%). Intentional exposures (4.9%) were mainly observed in patients older than 12 years of age (P < 0.001). The route of exposure was ingestion in 73.7% of the cases. A total of 455 exposures showed no symptoms or signs related to poisoning. High nicotine concentration in e-liquids was associated with an increase in hospital management (Odds-ratio from 1.77 to 2.60). Involuntary exposures to e-liquids occurred more often in children under the age of five, mainly by ingestion. Unlike intentional ingestions, unintentional ingestions rarely resulted in severe adverse events. These findings highlight the importance of ongoing surveillance to prevent such exposures and associated injuries, emphasizing the need for effective regulation of these products.

Carbon monoxide poisoning mortality in the United States from 2015–2021

Introduction Most carbon monoxide poisoning is preventable. Tracking of longitudinal trends in carbon monoxide-related mortality is needed to guide public health efforts. This study sought to describe mortality in the United States from carbon monoxide poisoning, examine the epidemiology of unintentional (“accidental”) and intentional exposures, and identify trends in both. Methods The Centers for Disease Control and Prevention’s Wonder databases were utilized to extract online data from National Center for Health Statistics files containing mortality data in the United States from 2015-2021. Extracted were deaths, crude death rates, intent of exposure, and demographics of persons dying from carbon monoxide poisoning, excluding cases related to fires. Also extracted was the number of suicidal deaths of all types. Carbon monoxide deaths related to consumer products were obtained from the Consumer Product Safety Commission. Information on state legislation mandating residential carbon monoxide alarms was obtained from online resources. Results Total carbon monoxide deaths decreased from 1,253 in 2015 to 1,067 in 2021. An increase in accidental poisoning deaths was offset by a larger decrease in intentional deaths, despite an increase in suicides of all types in the country. For the first time in the United States, accidental carbon monoxide deaths (543) outnumbered intentional deaths (524) in 2021. The increase in accidental deaths is consistent with those recently reported from carbon monoxide-emitting consumer products by the Consumer Product Safety Commission. Furthermore, even though over one-half of accidental deaths occurred at home, no evidence of a protective effect of state laws requiring residential carbon monoxide alarms was seen. Conclusions Accidental carbon monoxide poisoning deaths increased from 2015-2021 for the first time in four decades. Exploration of the possibility they are due to consumer products warrants attention and prevention efforts. We were unable to demonstrate the preventive effect of residential carbon monoxide alarm legislation.

Exploring the impact of social media exposure patterns on people’s belief in fake news during COVID-19: A cross-gender study

During COVID-19, fake news on social media seriously threatened public health. As a solution to this problem, this study examined how social media exposure patterns affect people being deeply harmed by fake news. Based on cognitive dissonance theory, this study investigated the effect of intentional and incidental exposure on belief in fake news through the mediating role of confirmation bias. The results show that intentional exposure positively influences confirmation bias and belief in fake news. Incidental exposure is the opposite. Our results also show that intentional exposure and confirmation bias negatively influence incidental exposure. Furthermore, these relationships remain unchanged by gender. This study provides theoretical and empirical contributions to reducing people’s belief in fake news.

Metformin-associated lactic acidosis reported to the United Kingdom National Poisons Information Service (NPIS) between 2010 and 2019: a ten-year retrospective analysis

Introduction Metformin toxicity following therapeutic use or overdose may result in metabolic acidosis with hyperlactatemia. This study aims to assess the relationship between serum lactate concentration, arterial pH, and ingested dose with severity of poisoning, and to identify if serum lactate concentration is a useful marker of severity in metformin toxicity. Methods A retrospective study of telephone enquiries relating to metformin exposures to the National Poisons Information Service between 2010 and 2019 from hospitals in the United Kingdom. Results Six-hundred and thirty-seven cases were identified; 117 involved metformin only and 520 involved metformin with other drugs. The majority of cases involved acute (87%) and intentional (69%) exposures. There was a statistically significant difference in doses between the Poisoning Severity Scores, as well as between intentional and unintentional or therapeutic error doses (P < 0.0001). The distribution of cases for each Poisoning Severity Score differed between the metformin only and metformin with other drugs cases (P < 0.0001). Lactic acidosis was reported in 232 cases. Serum lactate concentration and arterial pH differed across Poisoning Severity Scores. Arterial pH inversely correlated with ingested dose (r=-0.3, P = 0.003), and serum lactate concentration positively correlated with ingested dose (r = 0.37, P < 0.0001). Serum lactate concentration and arterial pH did not correlate with each other. Twenty-five deaths were recorded, all following intentional overdoses. Discussion The dataset focuses mostly on acute, intentional overdoses. Increasing ingested metformin dose, a higher serum lactate concentration and worsening arterial pH were all associated with an unfavourable Poisoning Severity Score in patients in both metformin only and metformin with other drugs groups. As serum lactate concentration did not correlate with arterial pH, it represents an independent marker of poisoning severity. Conclusions Data from the present study suggest that serum lactate concentration can be used to assess severity of poisoning in patients who have reportedly ingested metformin.

Acute organophosphorus toxicity in a regional hospital in Johannesburg, South Africa: A retrospective chart review.

Intentional and accidental organophosphorus exposures pose a significant healthcare-related burden on South African communities. This study will review the demographics, characteristics and clinical course of patients presenting with features of acute organophosphorus toxicity to a regional Emergency Centre in Johannesburg, South Africa. This was a retrospective chart review of all patients treated for possible acute organophosphorus toxicity from January 2020 to August 2021. A total of 205 patients were identified of which 134 patients were included in the study. The median age was 26 years with a male predominance (male= 56%, female=44%). 109 patients (81.3%) survived, 18 patients (13.4%) demised and the outcome of 7 patients (5.2%) was unknown. The median hospital length of stay was 8 days, (IQR= 5-13 days), and the longest hospital stay was 37 days in ICU. Atropinisation dose was significantly higher for intubated patients (median=140.0mg; IQR=90mg-219.5mg) compared to patients who were not intubated (median=60mg; IQR=20.5mg-120mg, p<0.05). The length of stay was significantly higher for intubated patients (median=11 days; IQR=7-15 days) compared to patients who were not intubated (median=5 days; IQR=3-8 days, p<0.00). There was a moderate positive correlation between atropinisation dose and length of stay (Correlation coefficient=0.37, p<0.00). There was a moderate negative correlation between atropinisation dose and cholinesterase level (Correlation coefficient= - 0.39, p<0.00). Of those reported to have adverse effects 78.6%, were related to atropine toxicity. Our study shows a high mortality rate secondary to organophosphorus toxicity. Significant exposures and thus higher doses of atropine were associated with increased length of stay and need for intubation. We found a high incidence of atropine-related adverse effects. More studies are needed to further establish the balance between the therapeutic and adverse effects of high-dose atropine as a treatment modality for organophosphorus toxicity.

Pulmonary pathogenesis in a murine model of inhaled arsenical exposure.

Arsenic trioxide (ATO), an inorganic arsenical, is a toxic environmental contaminant. It is also a widely used chemical with industrial and medicinal uses. Significant public health risk exists from its intentional or accidental exposure. The pulmonary pathology of acute high dose exposure is not well defined. We developed and characterized a murine model of a single inhaled exposure to ATO, which was evaluated 24h post-exposure. ATO caused hypoxemia as demonstrated by arterial blood-gas measurements. ATO administration caused disruption of alveolar-capillary membrane as shown by increase in total protein and IgM in the bronchoalveolar lavage fluid (BALF) supernatant and an onset of pulmonary edema. BALF of ATO-exposed mice had increased HMGB1, a damage-associated molecular pattern (DAMP) molecule, and differential cell counts revealed increased neutrophils. BALF supernatant also showed an increase in protein levels of eotaxin/CCL-11 and MCP-3/CCL-7 and a reduction in IL-10, IL-19, IFN-γ, and IL-2. In the lung of ATO-exposed mice, increased protein levels of G-CSF, CXCL-5, and CCL-11 were noted. Increased mRNA levels of TNF-a, and CCL2 in ATO-challenged lungs further supported an inflammatory pathogenesis. Neutrophils were increased in the blood of ATO-exposed animals. Pulmonary function was also evaluated using flexiVent. Consistent with an acute lung injury phenotype, respiratory and lung elastance showed significant increase in ATO-exposed mice. PV loops showed a downward shift and a decrease in inspiratory capacity in the ATO mice. Flow-volume curves showed a decrease in FEV0.1 and FEF50. These results demonstrate that inhaled ATO leads to pulmonary damage and characteristic dysfunctions resembling ARDS in humans.

Moral Judgments Impact Perceived Risks From COVID-19 Exposure

The COVID-19 pandemic created enormously difficult decisions for individuals trying to navigate both the risks of the pandemic and the demands of everyday life. Good decision making in such scenarios can have life and death consequences. For this reason, it is important to understand what drives risk assessments during a pandemic, and to investigate the ways that these assessments might deviate from ideal risk assessments. In a preregistered online study of U.S. residents (N = 841) using two blocks of vignettes about potential COVID exposure scenarios, we investigated the effects of moral judgment, importance, and intentionality on COVID infection risk assessments. Results demonstrate that risk judgments are sensitive to factors unrelated to the objective risks of infection. Specifically, activities that are morally justified are perceived as safer while those that might subject people to blame or culpability, are seen as riskier, even when holding objective risk fixed. Similarly, unintentional COVID exposures are judged as safer than intentional COVID exposures. While the effect sizes are small, these findings may have implications for public health and risk communications, particularly if public health officials are themselves subject to these biases.

Who Is Searching for Cyberhate? Adolescents' Characteristics Associated with Intentional or Unintentional Exposure to Cyberhate.

Cyberhate is one of the online risks that adolescents can experience online. It is considered a content risk when it is unintentionally encountered and a conduct risk when the user actively searches for it. Previous research has not differentiated between these experiences, although they can concern different groups of adolescents and be connected to distinctive risk factors. To address this, our study first focuses on both unintentional and intentional exposure and investigates the individual-level risk factors that differentiate them. Second, we compare each exposed group of adolescents with those who were not exposed to cyberhate. We used survey data from a representative sample of adolescents (N = 6,033, aged 12-16 years, 50.3 percent girls) from eight European countries-Czechia, Finland, Flanders, France, Italy, Poland, Romania, and Slovakia-and conducted multinomial logistic regression. Our findings show that adolescents with higher sensation seeking, proactive normative beliefs about aggression (NBA), and who report cyberhate perpetration, are at higher risk of intentionally searching for cyberhate contents compared with those who are unintentionally exposed. In comparison with unexposed adolescents, reporting other risky experiences was a risk factor for both types of exposure. Furthermore, NBA worked differently-reactive NBA was a risk factor for intentional exposure, but proactive NBA did not play a role and even decreased the chance of unintentional exposure. Digital skills increased both types of exposure. Our findings stress the need to differentiate between intentional and unintentional cyberhate exposure and to examine proactive and reactive NBA separately.

Oral Capecitabine Exposures and Use of Uridine Triacetate: A 20-Year Retrospective Analysis.

Capecitabine is an oral prodrug of 5-fluorouracil. Toxicity can occur during therapy as well as acutely with overdose and particular genetic susceptibilities. Uridine triacetate is an effective antidote if given within 96h of exposure. This study seeks to characterize accidental and intentional capecitabine exposures and uridine triacetate use, about which little has been published. A retrospective review of capecitabine exposures from 30 April 2001 to 31 December 2021 reported to a statewide poison control center was performed. All single-substance oral exposures were included. In total, 81 of 128 reviewed cases were included, with a median age of 63years. In total, 49 were acute-on-chronic exposures and 32 were acute exposures in capecitabine-naïve patients, 29 of which were accidental. Fifty-six (69%) were managed at home. Of these, none later recontacted the poison control center to report symptoms or were known to have later had healthcare facility evaluations. Of the 25 cases presenting for healthcare facility evaluation, 4 were acutely symptomatic. Thirteen were eligible for uridine triacetate, and six received it; no new or progressive toxicity was reported after. Three developed mild latent toxicity; otherwise, no morbidity or mortality was reported. Accidental acute-on-chronic and acute ingestions of capecitabine appear to be well tolerated; most cases were managed at home. Unfortunately, little is known regarding the threshold at which toxicity may present following exposures. The threshold may vary individually given genetic susceptibilities. Management was heterogeneous, likely reflecting inadequate guidelines. Further research is needed to better delineate at-risk populations and treatment strategies.

The role of decision tree and machine learning models for outcome prediction of bupropion exposure: A nationwide analysis of more than 14 000 patients in the United States.

Bupropion is widely used for the treatment of major depressive disorder and for smoking cessation assistance. Unfortunately, there are no practical systems to assist clinicians or poison centres in predicting outcomes based on clinical features. Hence, the purpose of this study was to use a decision tree approach to inform early diagnosis of outcomes secondary to bupropion overdose. This study utilized a dataset from the National Poison Data System, a 6-year retrospective cohort study on toxic exposures and patient outcomes. A machine learning algorithm (decision tree) was applied to the dataset using the sci-kit-learn library in Python. Shapley Additive exPlanations (SHAP) were used as an explainable method. Comparative analysis was performed using random forest (RF), Gradient Boosting classification, eXtreme Gradient Boosting, Light Gradient Boosting (LGM) and voting ensembling. ROC curve and precision-recall curve were used to analyse the performance of each model. LGM and RF demonstrated the highest performance to predict outcome of bupropion exposure. Multiple seizures, conduction disturbance, intentional exposure, and confusion were the most influential factors to predict the outcome of bupropion exposure. Coma and seizure, including single, multiple and status, were the most important factors to predict major outcomes.

Study of acid base imbalance in organophosphorus poisoning in intensive care patients of eastern Gujarat tribal region

Organophosphorus (OP) pesticides poisoning can result from occupational, accidental or intentional exposure. The compounds can be absorbed through skin, conjunctiva, oral mucosa, GI tract or respiratory tract. This study aimed to analyze arterial blood gas (ABG) analysis and serum cholinesterase (SC) activity in OP poisoning, to study clinical correlation of OP poisoning with the help of ABG analysis and SC and to compare factors of OP poisoning patients and control group. A total, 156 OP poisoning cases and 156 control participants were included in this study. The ABG and SC sample was processed at Central Clinical Biochemistry Laboratory, Medical College and Hospital, in a tertiary health care in eastern Gujarat. Most of the OP poisoning cases were young people 80% (&lt;50 years of age) with mean±SD age as 26.41±11.28 years (range: 11-80). Among these 90(57.69%) and 66(42.31%) were females and males respectively. While control participants with mean±SD age as 29.97±15.75 (range: 15-85) and male were 103(66%) and 53(34%) were females. Significant difference was found out between the age, Electrolytes: Na+, K+, Cl- and SC (p&lt;0.001), mean SC level in patients with the latent grade of poisoning was 1363.24±1326.76 IU/L, which is clinically significant (p&lt;0.001), no significant difference found between pH, pCO2, pO2, HCO3act and HCO3std (p&gt;0.05). This study concluded that mortality is directly proportionate to the amount of OP substances consumed, clinical severity of poison, SC levels, ABG analysis and electrolytes level in blood. This study can be improving survival or reduces mortality in patients with organophosphorus insecticide poisoning.

Mathematical model of spatial and temporal processing of broadband signals in satellite radio systems of broadband access and radio navigation

To effectively receive a useful broadband signal, it is necessary to compensate for distortions caused by the complex frequency-dependent coefficient of the receiving and transmitting antenna, multiplicative interference and noise from the heterogeneity of the propagation medium, additive interference and noise. Using only correlation processing under certain conditions will not allow receiving a useful broadband signal with the required quality. The article develops a mathematical model of spatio-temporal processing of broadband signals in satellite broadband access systems, showing that spatio-temporal processing should be carried out in two stages. At the first stage, space-time processing is carried out in the channel adaptively to the antenna array based on the formation of a complex frequency-dependent vector of weighting coefficients, which should change with a change in the signal-interference situation in real time, taking into account the change in the direction of radiation sources. At the second stage, correlation processing of the broadband signal is performed based on the use of long-length code sequences. This model is the basis for the development of methods for the formation and correlation (temporal) processing of broadband signals and methods of spatio-temporal processing of broadband signals under conditions of intentional and unintentional exposure. Based on the presented mathematical model of spatio-temporal processing of broadband signals, the main directions of increasing the noise immunity of radio-electronic systems are determined.

Ocular injury progression and cornea histopathology from chloropicrin vapor exposure: Relevant clinical biomarkers in mice

Ocular tissue is highly sensitive to chemical exposures. Chloropicrin (CP), a choking agent employed during World War I and currently a popular pesticide and fumigating agent, is a potential chemical threat agent. Accidental, occupational, or intentional exposure to CP results in severe ocular injury, especially to the cornea; however, studies on ocular injury progression and underlying mechanisms in a relevant in vivo animal model are lacking. This has impaired the development of effective therapies to treat the acute and long-term ocular toxicity of CP. To study the in vivo clinical and biological effects of CP ocular exposure, we tested different CP exposure doses and durations in mice. These exposures will aid in the study of acute ocular injury and its progression as well as identify a moderate dose to develop a relevant rodent ocular injury model with CP. The left eyes of male BALB/c mice were exposed to CP (20% CP for 0.5 or 1 min or 10% CP for 1 min) using a vapor cap, with the right eyes serving as controls. Injury progression was evaluated for 25 days post-exposure. CP-exposure caused a significant corneal ulceration and eyelid swelling which resolved by day 14 post exposure. In addition, CP-exposure caused significant corneal opacity and neovascularization. Development of hydrops (severe corneal edema with corneal bullae) and hyphema (blood accumulation in the anterior chamber) was observed as advanced CP effects. Mice were euthanized at day 25 post-CP-exposure, and the eyes were harvested to further study the corneal injury. Histopathological analyses showed a significant CP-induced decrease in corneal epithelial thickness and increased stromal thickness with more pronounced damage, including stromal fibrosis, edema, neovascularization, trapped epithelial cells, anterior and posterior synechiae, and infiltration of inflammatory cells. Loss of the corneal endothelial cells and Descemet's membrane could be associated with the CP-induced corneal edema and hydrops which could lead to long term term pathological conditions. Although exposure to 20% CP for 1 min caused more eyelid swelling, ulceration, and hyphema, similar effects were observed with all CP exposures. These novel findings following CP ocular exposure in a mouse model outline the corneal histopathologic changes that associate with the continuing ocular clinical effects. The data are useful in designing further studies to identify and correlate the clinical and biological markers of CP ocular injury progression with acute and long-term toxic effects on cornea and other ocular tissues. We take a crucial step towards CP ocular injury model development and in pathophysiological studies to identify molecular targets for therapeutic interventions.

Trends in pediatric nonprescription analgesic/antipyretic exposures during the COVID-19 pandemic

Objective To examine pediatric exposure trends involving selected nonprescription analgesics/antipyretics, before and during the COVID-19 pandemic. Methods Using descriptive and interrupted time-series analyses, we assessed monthly United States poison center data involving pediatric (<18 years) exposures to nonprescription paracetamol (acetaminophen), ibuprofen, acetylsalicylic acid, and naproxen before (January 2015-February 2020) and during (March 2020-April 2021) the pandemic. Statins and proton pump inhibitors (prescription or nonprescription) served as controls. Results Most nonprescription analgesic/antipyretic exposures (75–90%) were single-substance; unintentional exposures typically involved children <6 years (84–92%), while intentional exposures involved females (82–85%) and adolescents, 13–17 years (91–93%). Unintentional exposures among children <6 years, declined for all four analgesics/antipyretics immediately after the World Health Organization declared COVID-19 a pandemic (March 11, 2020), but most significantly for ibuprofen (30–39%). Most intentional exposures were classified as suspected suicide. Intentional exposures were relatively low and stable among males. Intentional exposures in females declined immediately after the pandemic was announced but subsequently increased to pre-pandemic levels for acetylsalicylic acid and naproxen and above pre-pandemic levels for paracetamol and ibuprofen. For paracetamol, female intentional exposures increased from 513 average monthly cases in the pre-pandemic to 641 average monthly cases during the pandemic; and reached 888 cases by the end of the study period in April 2021. While for ibuprofen, average monthly cases rose from 194 in the pre-pandemic, to 223 during the pandemic; and reached 352 cases in April 2021. Patterns were similar among females 6–12 and 13–17 years. Conclusion Nonprescription analgesic/antipyretic unintentional exposure cases declined among young children, while intentional exposure cases increased among females, 6–17 years, during the pandemic. Findings highlight the importance of safely storing medications and being alert to signs that adolescents may be in need of mental health support services; caregivers should seek medical care or call poison control centers for any suspected poisoning event.

Rising prescription stimulant poisoning in Australia: a retrospective case series

With rising therapeutic use worldwide, prescription stimulants are increasingly implicated in poisonings. Most of the limited research on stimulant poisoning focuses on illicit amphetamines. We aimed to investigate the clinical effects of intentional prescription stimulant poisoning. This is a retrospective review of hospitalised patients referred to a Poisons Information Centre and a toxicology unit following intentional exposures to prescription stimulants (dexamfetamine, lisdexamfetamine and methylphenidate) from 1 January 2018 through 31 December 2021. Patients were identified from both units’ databases and data extracted from medical records. To facilitate comparison a dexamfetamine-equivalent dose was calculated. There were 186 intentional exposures in 178 patients (median age 17 years, males 54%) over the study period, consisting of 44 (24%) dexamfetamine, 50 (27%) lisdexamfetamine and 92 (49%) methylphenidate exposures. Stimulant exposures rose annually from 34 presentations in 2018 to 61 in 2021. Deliberate self-poisoning accounted for 139 (75%) presentations and the remaining 47 (25%) were recreational. Co-ingestions were taken in 101 (54%) presentations, leaving 85 (46%) single-agent exposures with a median dexamfetamine-equivalent dose ingested of 135 mg (range 15-4500 mg). Of the single-agent exposures tachycardia (69%), hypertension (47%) and agitation (58%) were the commonest clinical features. Most patients (58%) had mild-moderate symptoms, managed solely with supportive cares or oral sedation. Twenty-three (27%) patients had severe agitation receiving parenteral sedation. Rhabdomyolysis occurred in 3 single-agent exposures (4%) and 8 (9%) had an acute kidney injury. Severe cardiovascular toxicity was rare, with one patient developing hypertensive crisis and another having a supraventricular tachycardia. The median length of stay for single-agent exposures was 11 h (IQR 5-19 h). Prescription stimulant poisoning appears to be rising and commonly results in tachycardia, hypertension, and agitation. Severe cardiovascular toxicity was rare.