Gas-phase autoxidation is an atmospheric chemistry reaction mechanism capable of transforming volatile organic compounds (VOCs) into highly oxygenated organic molecules (HOMs) that contribute to secondary organic aerosol (SOA) formation and growth. The key steps in this mechanism are intramolecular hydrogen shift (H-shift) reactions in organic peroxy radicals (RO2). For acyclic saturated molecules, these H-shift reactions are generally sufficiently slow that they cannot compete with atmospheric bimolecular reactions with NO x species, except for the 1,5 and 1,6 H-shifts, occurring via transition states (TS) of six- and seven-membered rings. Here, we report a surprisingly fast long-range H-shift reaction in a RO2 formed in the photo-oxidation of a volatile diether. In 1,2-diethoxyethane (1,2-DEE), we observe experimentally a 1,8 H-shift reaction that occurs with a rate coefficient on the order of ∼1 s-1 at 294 K - a rate that outcompetes all other RO2 unimolecular chemistry in the system and will, under most atmospheric conditions, outcompete bimolecular processes as well. Theoretical calculations indicate that activation of the C-H bond by an α-oxyl substituent and weaker transannular strain in the 1,8 H-shift transition state, combined with inductive deactivation of C-H bonds by a β-oxyl group at the abstraction site of competing 1,5 and 1,6 H-shifts, enable the longer-span 1,8 H-shift to be competitive. Our findings broaden the recognized reactivity of functionalized RO2 and highlight the potential for structurally diverse VOCs to undergo unexpected autoxidation pathways, producing HOMs at greater yield and with higher molecular complexity than previously anticipated.
Artisanal fisheries in the Canary Islands are an essential element of local livelihoods but face increasing challenges due to climate variability, access restrictions due incompatibility with other marine activities (i.e. wind farm and aquaculture), and resource depletion. Moreover, in recent years, fishers operating in the deep-water artisanal fishery of northern Lanzarote reported significant declines in catches, attributing up to 30% of losses to shark depredation on their captures while hoisting. We combined fisher surveys (n = 26), onboard monitoring trips (between 2022 and 2023), and time-series analyses of landings (2006-2023) to evaluate the magnitude of this stealing sharks interactions and their ecological context. Survey data indicated frequent shark encounters, mostly involving shortfin mako (Isurus oxyrinchus), thresher sharks (Alopias spp.), and hammerhead sharks (Sphyrna spp.). However, direct observations during 317 monitored fishing sets recorded only two possible shark-related losses, representing just 0.7% of total fishing effort. By contrast, wavelet analyses of landing series revealed strong correlations between the North Atlantic Oscillation (NAO) and catch variability, with 8-18 month lags. Periods of negative NAO (2014-2017) coincided with exceptional recruitment of deep-water fish species and subsequent record catches between 2018 and 2020, followed by sharp declines after 2021. Our findings suggest that catch losses by stealing sharks, although occasionally perceived as severe by fishers, exerts only a minor direct effect on catches. Instead, climate-driven fluctuations in recruitment and stock availability largely explain observed trends. These results underscore the importance of incorporating climate indices into fisheries assessments and management, while continuing to monitor shark-fishery interactions given their potential socioeconomic implications.
The Desperation Threshold Model (DTM) seeks to explain conflicting findings about the risk propensity of people living in poverty, predicting risk aversion when they can still meet their basic needs, and risk taking when they cannot. The DTM makes assumptions: that people have a conception of basic needs, that their ability to meet these motivates their decisions, and that they modulate risky decisions depending on their ability to do so. The realism of these assumptions has not yet been investigated. To start filling this gap, we investigated experiences of poverty through the lens of the DTM, using two complementary approaches: a pre-registered online survey with British participants (n = 300) and semi-structured qualitative interviews with very low-income individuals in France (n = 14). Our results imply that basic needs have both a context-general component and context-specific elaborations. Furthermore, participants often relied on social and institutional resources when experiencing financial adversity, indicating that measuring only personal income or wealth might not accurately capture the resources available to people. With respect to the DTM's main predictions, most individuals close to-but still above-the desperation threshold exhibited caution and took a safety-first approach, consistent with risk-averse behavior. Risky or antisocial behaviors (e.g., cheating, stealing) emerged only in rare instances of severe financial hardship and complete lack of external support. These results suggest that the DTM's main assumptions are empirically grounded but that they need to be qualified in specific ways. They also suggest that abstract models like the DTM can capture something about the experience of people living in conditions of poverty.
The task group (TG) is developing ICRP recommendations for radiological protection for a wide range of radiation emergencies and malicious events, complementing those given in ICRP Publication 146 (2020) for large nuclear accidents. The scope includes accidents, involving criticalities and operating faults, fires and explosions, inadvertent damage to sealed sources, and sabotage of nuclear facilities or materials, theft of radiation sources, radiological dispersal devices, and the tactical use of nuclear weapons. For all scenarios, a graded approach to protection is being taken, with the aim of making the advice as generally applicable as possible, accepting that specific guidance may be required for some distinctive aspects. As a result of the conflict in Ukraine, the TG has already published guidance for public protection in case of a nuclear detonation. In terms of communication, the TG will advise on how best to use social media during radiation emergencies and malicious events.
To examine and compare the impact of bio-banding with regard to age group competition on technical-tactical performance in young male and female handball players. An experimental study with a combined retrospective and cross-sectional design based on observational data analysis. By means of the percent of adult height attained estimation method, 86 players (45 boys and 41 girls) were bio-banded as pre-PHV (<89%, boys; <91%, girls), circa-PHV (89-92%, boys; 91-96%, girls), and post-PHV (>92%, boys; >96% girls). All players participated in two game formats - age group and bio-banding competition. Technical-tactical performance was recorded using the 'PlayerScore' index and other indicators of game actions. Internal consistency (Cronbach's α and ICC) and inter-observer reliability (Cohen's ĸ) were assessed with good or very good levels for all variables. A mixed two-way ANOVA was carried out and Cohen's d effect sizes were calculated for each variable. The bio-banding competition had a moderate impact compared to the age group competition on game-specific key technical-tactical performance indicators in boys, significantly increasing the number of 'assist-no goal' (p = 0.044; ηp2 = 0.11), 'steal/min' (p = 0.039; ηp2 = 0.11) and 'losing one-on-one' (p = 0.028; ηp2 = 0.08) in boys and decreasing 'winning one-on-one/min' actions (p = 0.029; ηp2 = 0.11) in girls. However, performance differences in favour of more advanced maturing players regardless of game format were observed in 'PlayerScore' in boys (p = 0.037; ηp2 = 0.08) and in 'goal' in girls (p = 0.004; ηp2 = 0.17). The interaction between game format and maturity status showed pre-PHV boys recorded more 'steal/min' (p < 0.05; ES = 1.70) and post-PHV girls scored more 'goal' (p < 0.05; ES = 1.06) in the bio-banding competition than in the age group competition. Moreover, in the bio-banding competition, higher values for 'goal' (p < 0.01; ES = 1.61), 'assist-no goal' (p < 0.05; ES = 1.57), and 'technical error' (p < 0.05; ES = 1.23) among post-PHV boys, higher values for 'steal/min' (p < 0.05; ES = 1.43) among pre-PHV boys, and higher values for 'goal' among post-PHV girls (p < 0.05; ES = 1.40) were recorded. Maturity status-matched competition had a positive but limited effect on technical-tactical performance. This alternative grouping strategy could be considered effective in manipulating the technical-tactical performance of young players.
Speech and language impairments, long recognized as early symptoms of Alzheimer's disease (AD), can now be quantified with unprecedented precision due to recent advances in natural language processing (NLP) and artificial intelligence (AI). Despite growing interest in AI-enabled speech biomarkers, few studies have linked spontaneous speech to biologically verified AD, and most have focused on English-language data or acoustic features with limited linguistic interpretability. Here, we present the first end-to-end machine-learning framework for automatic AD detection from German speech, using clinical-biological criteria validated by cerebrospinal fluid (CSF) biomarkers. 44 participants were included: 22 biomarker-defined AD cases from a prospective observational study (German Clinical Trials Register, DRKS00030633) and 22 socio-demographically matched cognitively healthy controls (CHC). Connected speech was elicited using the standardized Cookie Theft picture description task. Recordings were transcribed with a state-of-the-art automatic speech recognition (ASR) system. From these transcripts, 32 theory-driven linguistic biomarkers were computed with an advanced NLP tool, falling into three categories: information-theoretic, lexical richness, and syntactic. AD-versus-CHC classification used five supervised models (logistic regression, support vector machine with a radial basis function kernel, random forest, gradient boosting, XGBoost) under stratified five-fold cross-validation, with stability-based recursive feature elimination performed within training folds. Model interpretability was assessed using SHapley Additive exPlanations (SHAP). Recursive feature elimination retained seven of 32 candidate speech biomarkers as consistently informative across folds. Trained on this subset, all classifiers showed strong discrimination between biomarker-defined AD and CHC. Logistic regression, SVM, random forest, and gradient boosting achieved ~91% mean accuracy with F1 ≈ 0.90 and sensitivity ≈ 0.90, while XGBoost was slightly lower (~89% accuracy). SHAP analyses indicated that model decisions were primarily driven by information-theoretic and structural markers: lower compressibility, reduced lexical density, shorter clauses and sentences, and weaker predictive sequencing indexed by higher-order n-gram statistics. Clinically meaningful linguistic biomarkers can be robustly derived from spontaneous speech, even in small, well-characterized clinical samples. Theory-driven features and stability-focused modeling show that information-theoretic and structural properties of connected speech capture core Alzheimer-related impairments with robust classification performance. These findings support AI-enabled speech analysis as a non-invasive, scalable complement to established biological biomarkers of Alzheimer's disease.
Anomalous coronary artery origin from pulmonary artery and coronary-pulmonary fistulas are the major causes of ischemic cardiopathy in children. Both anomalies are characterized by a connection between a higher and a lower pressure chamber causing coronary steal. However, several mechanisms and associated lesions may be responsible of the different presentations of the "coronary steal phenomenon". The aim of this review is to highlight the different embryology, anatomical features, clinical presentation, and the diagnostic and therapeutic strategy of these coronary anomalies, despite their similar pathophysiology.
Ischemic monomelic neuropathy (IMN) is an under-recognized complication of arteriovenous access creation among hemodialysis patients, which may lead to disability. It is marked by acute pain and sensorimotor deficits without ischemia. The true incidence of IMN remains unclear due to the paucity of reported cases. Treatment guidelines have not been established. We report a case of IMN of the right hand after the creation of a second vascular access for hemodialysis. Electrophysiologic tests confirmed the diagnosis. The patient underwent a delayed arteriovenous (AV) fistula breakdown and AV graft plication. Symptoms resolved immediately after. We also did a review of the literature. Given the potential for reversibility, early recognition is essential. Electrodiagnostic tests are valuable in the diagnosis. Surgical interventions appear to relate to better outcomes.
Anomalous left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital coronary anomaly in which the left coronary artery originates from the pulmonary artery, resulting in myocardial ischemia due to coronary steal after postnatal reduction in pulmonary artery pressure. Most patients present in infancy with heart failure, but a subset survives into later childhood or adulthood through extensive collateralization from the right coronary artery. Late presenters typically demonstrate a dilated, tortuous right coronary artery with retrograde flow into the pulmonary artery. Surgical correction is recommended at all ages; however, optimal management in older patients remains debated. This review summarizes the existing literature and discusses surgical strategies for adult-onset ALCAPA. Surgical repair of adult-onset ALCAPA aims to eliminate coronary steal and restore a physiologic two-coronary system. The choice of technique depends on anatomic factors, including the origin of the left coronary artery, its distance from the aorta, vessel length, and the extent of intercoronary collaterals. Direct reimplantation of the left coronary artery into the aorta is preferred when feasible, as it provides durable restoration of normal coronary physiology, though it may be limited by tension or inadequate coronary length. The Takeuchi procedure offers an alternative when reimplantation is not possible but carries risks such as baffle stenosis and pulmonary artery obstruction. Coronary artery bypass grafting may be considered in selected adults, though competitive flow from collaterals and long-term graft durability remain concerns. Additionally, new techniques such as modified Cabrol and modified Takeuchi may offer even greater promise for the future but will require further research to establish their place in the field.
Security is the main attribute when dealing with information exchange. Confidential information theft, data loss, and data manipulation are conceivable results of security events. Different forms of data hiding are Cryptography and Steganography. Cryptography converts information into an unreadable form, and steganography hides the existence of information. The proposed work experiments with Advanced Blowfish Encryption based on an extended round function integrity with Chaotic Image Quantization (ABECIQ) as a security mechanism. ABECIQ aims to introduce a novel security mechanism that combines cryptography and steganography with the key generation scenario using a genetic algorithm. Initially, using a genetic algorithm and real-time clock values, the secret keys are created. The Blowfish algorithm's round function 'F' is modified by adding crossover and mutation functions. The generated ciphertext is embedded in an image using the chaotic-quant technique. The proposed work is analysed using parameters of the Avalanche effect, Entropy values, Execution time, Attack scenario, Correlation coefficient, and Peak Signal-to-Noise Ratio (PSNR) values. The experiments demonstrate that the ABECIQ algorithm achieves PSNR values within the range of 65 to 74 dB while SSIM values are above 0.999, which indicate high imperceptibility. The generated keys also show entropy values which are close to the theoretic maximum of 8 bits per character. In addition, the proposed algorithm shows high throughput thereby indicating improved computational efficiency compared to the existing algorithm. The analysis shows that ABECIQ provides better results than the existing Chaotic, Blowfish Encryption, as well as AES-RDH algorithm. ABECIQ is evaluated with different text files of sizes 4KB and 12KB demonstrating better PSNR, MSE, SSIM, and Correlation Coefficient. In addition, the time complexity for ABECIQ has also been analyzed for embedding process.
Coronary arteriovenous fistulas (CAFs) are abnormal communications between coronary arteries and cardiac chambers or great vessels. They are usually congenital but may be acquired after trauma, surgery, or percutaneous procedures. Although often incidental in childhood, hemodynamically significant CAFs in adults can cause myocardial ischemia, arrhythmia, heart failure, or endarteritis. Evidence to guide management is limited, and multidisciplinary evaluation at centers experienced in both percutaneous and surgical approaches is recommended. A 60-year-old man with hypertension and prior left anterior descending coronary artery stenting presented with worsening chest pain that progressed to unstable angina. A coronary angiogram showed a new middle right coronary artery stenosis that was treated with a stent. Coronary angiography identified a high-flow fistula from the proximal right coronary artery draining into the superior vena cava. Persistent symptoms, right-sided chamber enlargement, and a Qp:Qs of 1.5 indicated a significant shunt and functional ischemia from coronary steal. Initial attempts to deploy a 6-mm Amplatzer Vascular Plug II failed due to inadequate catheter support across a tortuous tract. An anchoring balloon technique aid, permitting delivery and successful deployment of the AVP II at the arterial origin with complete angiographic occlusion. CAFs are a rare but treatable cause of angina and myocardial ischemia. Management should be individualized and planned by a multidisciplinary Heart Team. Transcatheter closure is effective in suitable anatomies, and balloon-assisted anchoring is a useful technique to facilitate device delivery in elongated or tortuous fistulas.
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Isolated left common carotid artery (ILCCA) is a rare cardiovascular malformation. Its core imaging feature is the anomalous connection of the left common carotid artery (LCCA) to the pulmonary artery, rendering it the rarest subtype of right aortic arch malformation. Reversed blood flow in the LCCA has been identified in the vast majority of reported cases. This malformation induces a left-to-right shunt via the common carotid artery and the circle of Willis, which subsequently leads to LCCA-steal syndrome. To date, no studies have reported the composition of this left-to-right shunt nor the neurological complications secondary to LCCA-steal syndrome. This case report elucidates the composition of the left-to-right shunt and the underlying mechanism by which the malformation elicits the steal syndrome.
Iron is an essential element that can be growth-limiting in microbial communities, particularly those present within host organisms. To acquire iron, many bacteria secrete siderophores, secondary metabolites that chelate ferric iron. These iron chelates can be transported back into the cell via TonB-dependent transporters in the outer membrane, followed by intracellular liberation of the iron. Pathogenic Escherichia coli and Salmonella produce siderophores during gut infection. In response to iron starvation, the human gut symbiont Bacteroides thetaiotaomicron upregulates an iron piracy system, XusABC, which steals iron-bound siderophores from the invading pathogens. Here, we investigated the molecular details of xenosiderophore uptake across the outer membrane by the XusAB complex. Our crystal and cryogenic electron microscopy structures explain how the XusB lipoprotein recognizes iron-bound xenosiderophores and passes them on to the XusA TonB-dependent transporter. Moreover, we show that Xus homologues can transport a variety of siderophores with different iron-chelating functional groups.
BACKGROUND Subclavian steal syndrome (SSS) is typically caused by atherosclerotic occlusion of the proximal subclavian artery. While atherosclerosis is the primary etiology, clinical awareness of non-atherosclerotic triggers is essential for accurate diagnosis. Non-atherosclerotic causes, such as arterial kinking, are exceedingly rare and are frequently overlooked in the differential diagnosis of vertebrobasilar insufficiency. This report describes a case of partial SSS secondary to mechanical kinking of the brachiocephalic trunk (BCT) in an elderly patient, emphasizing the need to consider anatomical variations even without obstructive plaques. CASE REPORT A 66-year-old woman with a history of stroke and atrial fibrillation (CHA₂DS₂-VASc score of 5) was referred for color Doppler ultrasound of the carotid and vertebral arteries. Imaging revealed Stage II (intermittent) flow reversal in the right vertebral artery, characterized by a distinctive mid-systolic deceleration pattern. Subsequent computed tomography angiography (CTA) excluded atherosclerotic disease but demonstrated a severe 90-degree angulation (kinking) at the BCT origin. This anatomical variation created a pressure gradient sufficient to induce a partial steal phenomenon. Given the patient's high thromboembolic risk and clinical stability, a conservative management approach with optimized anticoagulation and strict cardiovascular risk control was prioritized. CONCLUSIONS BCT kinking should be considered a potential hemodynamic cause of SSS when atherosclerosis is absent. This case highlights the importance of multi-modal imaging (color Doppler ultrasound and CTA) in identifying rare anatomical triggers for flow inversion. A conservative strategy is safe when flow in the basilar artery remains stable.
Anomalous origin of the left circumflex artery (LCx) from the pulmonary artery (ACxAPA) is rare. We report a case of successful percutaneous occlusion. A 74-year-old man presented with progressive dyspnea on exertion. Echocardiography showed a left ventricular ejection fraction of 45% with inferior hypokinesis. Nuclear imaging revealed an inferior perfusion defect. Coronary computed tomography angiography demonstrated an anomalous LCx originating from the right pulmonary artery. Right heart catheterization and coronary angiography confirmed the diagnosis. Injection of the coronary arteries revealed retrograde filling of the LCx with drainage into the right pulmonary artery. After multidisciplinary discussion, percutaneous closure was pursued. Using femoral venous access, an 8-mm vascular plug was deployed at the origin of the anomalous artery, with complete occlusion of the ostium. Left ventricular ejection fraction improved immediately, and this improvement was sustained. Although the literature on ACxAPA is sparse, this case indicates that transcatheter occlusion can be effective in carefully selected adults. Recognizing and documenting ACxAPA is essential. Management should be individualized by a heart team; percutaneous occlusion is an option when anatomy is favorable.
Picture description tasks, such as the Cookie Theft task, are widely used in neuropsychological assessments to detect cognitive impairment. However, manual scoring is time-consuming, requires specialized training, and is subject to interrater variability. Recent advancements in natural language processing, particularly large language models (LLMs), offer a promising solution to automate and standardize the scoring process. This study evaluated the performance and reliability of five LLMs (GPT-4 Turbo, GPT-4o, Claude 3 Opus, Claude 3 Sonnet, and Llama 3 70b) in scoring the Cookie Theft picture description task. A subset of 25 participants were selected from the DementiaBank corpus. The LLMs were tasked with scoring 22 content units in the participants' responses using various prompt strategies, including few-shot learning, prompt chaining, and self-consistency. LLM performance was compared to the consensus score of three human raters. LLMs demonstrated comparable accuracy to human raters in scoring the Cookie Theft task, with no significant differences in mean absolute error (MAE) between the best performing models and human raters. Few-shot learning significantly improved LLM performance, while prompt chaining and self-consistency showed limited benefits. Claude 3 Opus and GPT-4o exhibited the highest accuracy and reliability. Notably, LLMs showed significantly higher interrater reliability compared to human raters. The findings demonstrate the potential of LLMs to accurately and reliably score picture description tasks, offering a promising approach to streamline and standardize neuropsychological assessments. By automating the scoring process, clinicians and researchers can benefit from increased efficiency, reduced subjectivity, and improved scalability in evaluating cognitive functions.
Peer review is the cornerstone of scholarly publishing and, in medicine, the ultimate guarantor of the reliability of clinical evidence that informs guidelines, therapeutic strategies, and patient care. However, the current peer review system is increasingly strained by bias, abuse, and reviewer overload. Favoritism toward prominent authors, editorial "nepotism," coercive citation practices, superficial evaluations, and even documented cases of idea theft from confidential manuscripts undermine the trustworthiness of the scientific literature upon which clinical decisions depend. In this paper, we argue that artificial intelligence (AI) and large language models (LLMs) offer a transformative opportunity to strengthen the integrity and efficiency of medical peer review. AI-driven tools can perform rapid consistency checks, detect statistical errors or plagiarism, and enforce compliance with ethical and methodological standards across thousands of manuscripts. Early implementations of AI-guided review platforms, plagiarism detectors, and citation-anomaly algorithms demonstrate that machine assistance can make reviews more thorough, objective, and reproducible. At the same time, we acknowledge the limitations of AI, including hallucinations, a lack of human judgment, and risks to confidentiality if misused. To address these concerns, we propose a hybrid model in which AI handles routine screening and technical tasks under strict safeguards, while human experts retain final responsibility for scientific evaluation. This human-AI partnership may represent an essential step toward improving the quality, fairness, and reliability of the clinical evidence base.
Cyberbullying represents a major concern for students, yet most studies rely on quantitative and adult-centered perspectives. Understanding adolescents' views on cyberbullying is crucial for prevention. We conducted sixteen focus groups with 220 Italian middle school students (ages 11-13). Transcripts were inductively analyzed to identify domains, core ideas, and the occurrence of categories (general, typical, variant) using the Consensual Qualitative Research method. Four main domains emerged: definitions, behaviors, roles, and coping strategies. Adolescents defined cyberbullying as a hostile online interaction marked by publicity, often followed by anonymity; few mentioned repetition. Direct acts such as insults, threats, and non-consensual image sharing were viewed as the most harmful behaviors, followed by impersonation and identity theft, while online challenges and other forms were less mentioned. Students mainly perceived cyberbullying as a dyadic interaction between bully and victim, showing limited awareness of pro-bullies, few references to bystanders, and no mention of defenders. Finally, participants focused on victims' responses with little attention to bystanders' coping strategies. By revealing a nuanced understanding of cyberbullying, adolescents emphasize the need for prevention programs that not only address online risks but also build on their own language, perspectives, and experiences.
Dialysis access-associated steal syndrome (DASS) is an uncommon but potentially limb-threatening complication of hemodialysis arteriovenous access. DASS results from preferential shunting of arterial blood into the low-resistance access circuit, causing distal hypoperfusion and symptoms ranging from hand coolness and paresthesias to skin ulceration and tissue loss. We discuss the case of a 32-year-old patient with end-stage renal disease on hemodialysis who presented with prolonged bleeding after dialysis from their right upper-extremity arteriovenous fistula. The patient then underwent fistulography with endovascular treatment of venous outflow pathology and pseudoaneurysms. One month later, the patient developed worsening dialysis-associated forearm/hand pain and paresthesias. Repeat angiography demonstrated poor anterograde distal forearm perfusion with flow reversal into the fistula, absence of proximal arterial inflow stenosis, and restoration of distal perfusion with venous outflow compression, supporting the diagnosis of DASS. This case highlights the importance of recognizing dialysis-associated ischemic symptoms while reviewing a mechanism-based diagnostic approach used to guide management.