Search Results (93)

Volcanic super-eruptions can perturb atmospheric composition and climate-relevant radiative properties in ways that are not captured by simple scaling from Pinatubo-like events. This study presents a reduced-order regime theory for the coupled evolution of stratospheric sulfur, sulfate aerosol burden, reactive halogens, ozone loss, stratospheric thermal adjustment, and aerosol residence time. The analysis is intended as an interpretive tool for organizing sulfur-rich volcanic scenarios, comparing literature-based benchmark classes, and designing chemistry–climate model experiments, rather than as an event-specific calibration or a substitute for three-dimensional models. Four control parameters structure the response: sulfur loading relative to microphysical saturation, effective halogen strength, ash-uptake efficiency, and dynamical lifetime sensitivity, with hemispheric asymmetry treated diagnostically. An external consistency check against published Pinatubo-like, idealized 10–40 teragrams of sulfur (Tg S), Toba-like, and Los Chocoyos-like responses is used to evaluate whether the reduced theory reproduces the expected rank ordering of aerosol saturation, forcing-efficiency decline, ozone-loss amplification, ash-driven sulfur suppression, and residence-time sensitivity. This comparison does not assign pointwise error margins against three-dimensional model output; it evaluates regime membership, sign of response, rank ordering, and broad magnitude behavior. The main conclusion is that volcanic super-eruption impacts are governed by interacting regime transitions rather than by sulfur mass alone. Microphysical saturation can limit forcing efficiency, halogens can shift the system toward chemically amplified ozone depletion, ash uptake can reduce the effective sulfur burden during the early phase, and dynamical state can control persistence and hemispheric expression. By separating these mechanisms, the study provides a compact basis for interpreting large volcanic perturbations to atmospheric chemistry and for designing targeted model experiments on extreme eruption scenarios. Full article

Background: In older people, syphilis diagnosis might be undervalued due to both clinical conditions and age-related changes that obscure symptom presentation and physician discomfort with sexual history-taking, creating a dual barrier to timely recognition. Methods: Case presentation with literature review. Results: An 80-year-old woman was referred to the Dermatology Department of Cagliari University by her oncologist, with a 2-month history of intermittent episodes of pruritus associated with papular–nodular skin lesion eruptions, accompanied with asthenia, night sweats, and unintentional weight loss, indicative of a paraneoplastic syndrome or an adverse drug reaction. Careful evaluation indicated the need to perform serological testing, which confirmed secondary syphilis (RPR 1:64 and TPHA 1:5120). Specific questioning regarding sexual behaviors pointed out oral and anal intercourse. The 83-year-old husband did not have active lesions at visit but reported a self-healing generalized skin rash, episodes of asthenia, arthralgia, and headache he had never suffered before. Blood tests showed positive RPR 1:64 and TPHA 1:5120. Targeted sexual history assessment disclosed patient’s engaging with commercial sex workers, clarifying the chain of transmission in this conjugal STI case. Treatment with Benzathine penicillin G 2.4 million units IM in a single dose resulted in complete recovery in both patients. Conclusions: The observation highlights the importance of maintaining a high index of suspicion for syphilis even at advanced age. Persistent stigma regarding elderly sexuality should be faced, and targeted interventions are necessary to improve the clinician’s ability to identify STIs in older adults, but also to reduce sexual stigma and taboo persistence in the general population. Full article

Hydrologic models are instrumental in understanding the behavior of the Nile River Basin (NRB), yet their effectiveness is often limited by the basin’s complex hydrology and sparse observational records. This study applies a basin-scale hydrological modeling approach to simulate near-natural, pre-reservoir flow conditions in the NRB, while incorporating lake and wetland submodels. The basin was discretized into 34 sub-watersheds with an outlet at Aswan. The conceptual GR4J rainfall–runoff model was implemented within the Raven modeling framework, chosen for its parsimony and suitability for data-limited conditions. Multi-objective calibration used discharge data from the Global Runoff Data Centre (GRDC), supplemented by digitized historical records to improve spatial and temporal coverage. A stepwise calibration strategy was applied at 18 sites, focusing on pre-reservoir periods to capture natural flow dynamics. The calibrated model reproduces observed discharges with high skill. At the Aswan outlet, Nash–Sutcliffe Efficiency (NSE) values were 0.87 (calibration) and 0.80 (validation), with percent bias (PBIAS) values of 6.1% and 5.0%, respectively. Model performance was strongest in the Blue Nile, White Nile headwaters, and the Nile main stem. The model also successfully simulated the hydrological step-change observed in Lake Victoria during the 1960s, underscoring its robustness in simulating regional hydroclimate disruptions. This calibrated model enables reconstruction of historical Nile discharge and simulation of past hydrologic disturbances, including those driven by major volcanic eruptions over the past millennia. Full article

Urticaria is a mast cell-mediated disorder commonly encountered in women of reproductive age, making its interaction with pregnancy clinically relevant. Gestation induces profound hormonal and immunologic adaptations—including shifts between Th1/Th17 and Th2/Treg responses and sustained exposure to sex steroids and placental hormones—that can modulate mast cell reactivity. As a result, chronic urticaria (CU) shows heterogeneous behavior during pregnancy: approximately half of patients improve, one third worsen, and the remainder remain stable. Pregnancy also presents several urticaria-like dermatoses, notably polymorphic eruption of pregnancy (PEP/PUPPP), atopic eruption of pregnancy (AEP) and pemphigoid gestationis (PG), as well as rare hormone-induced hypersensitivity reactions. Additionally, systemic disorders such as intrahepatic cholestasis of pregnancy (ICP), chronic kidney disease–associated pruritus and urticarial vasculitis may mimic urticaria but differ markedly in prognosis, maternal–fetal risk and management. Given this complexity, accurate diagnosis requires integration of temporal pattern, lesion morphology and duration, distribution, systemic features and targeted investigations, as outlined in the diagnostic algorithm proposed. Most pregnancy-specific eruptions are benign, whereas PG, ICP and urticarial vasculitis warrant prompt recognition due to potential fetal implications. Management of CU in pregnancy generally follows standard guidelines, with second-generation H1-antihistamines as first-line therapy and omalizumab reserved for severe refractory cases. Full article

Stromboli’s volcanic activity fluctuates in intensity and style, and periods of heightened activity can trigger hazardous events such as crater collapses and lava overflows. This study investigates the volcano’s explosive behavior surrounding the 19 May 2021 crater-rim failure, which primarily affected the N2 crater and partially involved N1, by integrating high-frequency thermal imaging and high-resolution unmanned aerial system (UAS) surveys to quantify eruption parameters and vent morphology. Typically, eruptive periods preceding vent instability are characterized by evident changes in geophysical parameters and by intensified explosive activity. This is quantitatively monitored mainly through explosion frequency, while other eruption parameters are assessed qualitatively and sporadically. Our results show that, in addition to explosion rate, the spattering rate, the predominance of bomb- and gas-rich explosions, and the number of active vents increased prior to the collapse, reflecting near-surface magma pressurization. UAS surveys revealed that the pre-collapse configuration of the northern craters contributed to structural vulnerability, while post-collapse vent realignment reflected magma’s adaptation to evolving stress conditions. The May 2021 events were likely influenced by morphological changes induced by the 2019 paroxysms, which increased collapse frequency and amplified the 2021 failure. These findings highlight the importance of integrating quantitative time series of multiple eruption parameters and high-frequency morphological surveys into monitoring frameworks to improve early detection of system disequilibrium and enhance hazard assessment at Stromboli and similar volcanic systems. Full article

The occurrence of cysts and tumors in pediatric patients varies across different age groups. Follicular and dentigerous cysts are among the most common lesions. However, typical odontogenic tumors in juvenile patients are not frequently observed. Early stages of cyst and odontogenic tumor development might exhibit some similar characteristics due to the presence of unerupted teeth or their relationship with various stages of tooth formation and eruption. Many small lesions are discovered accidentally on routine orthopantomography (OPG), while the bigger ones manifest themselves as bone swelling, cortical perforation, or displacement and mobility of teeth. Each odontogenic tumor has characteristic clinical and radiological features. Biopsy of larger lesions, or incisional biopsy of smaller lesions, allows detailed histopathological evaluation to determine tumor type and growth behavior and guide appropriate treatment planning. In some cases, atypical signs on OPGs, like asymmetry in dental follicles, occurrence of round or oval bone lesions near impacted or retained teeth, and visibility of irregular radiolucent, radiopaque, or mixed jawbone lesions, might suggest the occurrence of some possible odontogenic tumor in juvenile patients. Each case should be handled individually. In this case, we demonstrate how atypical appearances of dental follicles on panoramic radiographs may not correspond with cone-beam computed tomography findings and may indicate the early stages of odontogenic myxoma in a juvenile patient. Full article

Background: Herpes zoster (HZ) represents a substantial public health concern among aging populations, yet regional variability in clinical patterns and risk determinants remains insufficiently documented. In southeastern Romania, epidemiological data are limited, and the combined influence of demographic, behavioral, and metabolic factors on disease severity has not been systematically evaluated. Methods: We performed a retrospective observational study including 100 consecutive patients diagnosed with HZ between 2019 and 2023 in a dermatology department in southeastern Romania. Demographic characteristics, lifestyle behaviors, anthropometric status, clinical manifestations, and outcomes were extracted from medical records. Associations between categorical variables were assessed using Chi-square tests and Cramer’s V, while interaction patterns were explored through log-linear modeling. Heatmaps were generated in Python (version 3.10) using the Matplotlib library (version 3.7.1) to visualize distribution patterns and subgroup relationships. Results: The cohort showed a marked age dependence, with 77% of cases occurring in individuals ≥ 60 years, consistent with immunosenescence-driven reactivation. Women represented 59% of cases, and 84.7% of female patients were postmenopausal. Urban residents predominated (91%). Vesicular eruption (84%) and acute pain (79%) were the most frequent symptoms. Localized HZ was observed in 81% of cases, while ophthalmic involvement (11%) and disseminated forms (8%) were less common. Lifestyle factors significantly influenced clinical severity: smokers, alcohol consumers, and sedentary individuals exhibited higher proportions of postherpetic neuralgia (PHN) and ocular complications (p < 0.001). Overweight and obese patients demonstrated a higher burden of PHN, suggesting a role for metabolic inflammation, although BMI was not associated with incidence. No significant association between age category and complication type was detected, likely due to small subgroup sizes despite a clear descriptive trend toward increased severity with advanced age. Conclusions: These findings support a multifactorial model of HZ severity in southeastern Romania, shaped by age, lifestyle behaviors, hormonal status, and metabolic risk. While incidence patterns align with international data, the strong impact of modifiable factors on complication rates highlights the need for targeted prevention and individualized risk assessment. Results offer a regional perspective that may inform future multicenter investigations. Full article

Background: X-linked hypophosphatemic rickets (XLH) is a rare hereditary disorder characterized by renal phosphate wasting and impaired bone mineralization. Oral manifestations such as spontaneous periapical lesions and dental abscesses in the absence of caries or trauma may precede systemic features in XLH due to underlying dentin hypomineralization and enamel–dentin junction defects, and could serve as early diagnostic indicators. Case Report: We report on the case of a 4-year-old boy referred to our pediatric dental unit with recurrent intraoral fistulas persisting over the past year. Clinical examinations and an orthopantomogram revealed extensive root resorption and periapical pathology affecting multiple primary molars without evident caries or trauma. Laboratory investigations showed hypophosphatemia, elevated renal phosphate loss, and raised inflammatory markers (CRP (C-reactive protein) and granulocytes). Genetic testing of the child and his mother confirmed a diagnosis of X-linked hypophosphatemic rickets. Management: Due to behavioral challenges, treatment proceeded with difficulty over multiple visits. Endodontic treatment was initiated using a formalin–resorcinol technique; however, several primary molars developed progressive necrosis and required extraction. Orthodontic space maintainers were placed to preserve arch integrity and support future eruption. The patient remains under follow-up and is currently awaiting Burosumab therapy. Despite systemic management, spontaneous necroses of the primary molars persist, highlighting the refractory nature of dental involvement in XLH. Conclusions: This case underscores the pivotal role of pediatric dentists in recognizing systemic diseases through oral findings and demonstrates the challenges of managing XLH-related dental pathology, even under targeted systemic therapy. Early interdisciplinary collaboration is essential to optimize both dental and systemic outcomes in affected children. Full article

Expansive soils undergo significant volume changes with moisture fluctuations, posing persistent challenges for infrastructure due to heave, settlement, and loss of bearing capacity. Stabilization is a common mitigation strategy, though traditional binders, such as cement and lime, are associated with high energy consumption and considerable CO₂ emissions. In this context, identifying low-carbon alternatives is essential. This study evaluates the short-term behavior of expansive marly clays from southern Spain stabilized with volcanic ash generated during the 2021 Tajogaite eruption (La Palma, Canary Islands, Spain). Volcanic ash was incorporated in different proportions to assess its performance as a natural pozzolan, while natural hydrated lime was used both as a direct stabilizer and as an activator to enhance ash reactivity. A key methodological contribution of this research is the monitoring of lime reactivity throughout storage, using XRD and TGA to quantify portlandite loss and partial carbonation before mixing—an aspect seldom addressed in stabilization studies. The experimental program included chemical and mineralogical characterization, compaction, Atterberg limits, free swelling, unconfined compressive strength, and direct shear tests on natural and stabilized mixtures. The results show that volcanic ash, particularly when lime-activated, substantially improves volumetric stability. Free swelling decreased from 11.9% in the natural soil to values as low as 1.7%, while dry density increased and plasticity decreased. Strength gains were modest under short-term conditions, consistent with the limited time for pozzolanic reactions to develop. The combined use of volcanic ash and lime reduced the lime demand required to achieve equivalent volumetric control, offering an eco-efficient and technically viable alternative for stabilizing expansive marly clays. Full article

In this paper, we propose the Adaptive Volcano Support Vector Machine (AVSVM)—a novel classification model inspired by the dynamic behavior of volcanic eruptions—for the purpose of enhancing malware detection. Unlike conventional SVMs that rely on static decision boundaries, AVSVM introduces biologically inspired mechanisms such as pressure estimation, eruption-triggered kernel perturbation, lava flow-based margin refinement, and an exponential cooling schedule. These components work synergistically to enable real-time adjustment of the decision surface, allowing the classifier to escape local optima, mitigate class overlap, and stabilize under high-dimensional, noisy, and imbalanced data conditions commonly found in malware detection tasks. Extensive experiments were conducted on the UNSW-NB15 and KDD Cup 1999 datasets, comparing AVSVM to baseline classifiers including traditional SVM, PSO-SVM, and CNN under identical computational settings. On the UNSW-NB15 dataset, AVSVM achieved an accuracy of 96.7%, recall of 95.4%, precision of 96.1%, F₁-score of 95.75%, and a false positive rate of only 3.1%, outperforming all benchmarks. Similar improvements were observed on the KDD dataset. In addition, AVSVM demonstrated smooth convergence behavior and statistically significant gains (p < 0.05) across all pairwise comparisons. These results validate the effectiveness of incorporating biologically motivated adaptivity into classical margin-based classifiers and position AVSVM as a promising tool for intelligent malware detection systems. Full article

Several factors have been associated with delayed eruption of primary teeth. Thus, the objective of the study was to test a path model of the direct and indirect birth-related risk factors influencing the age of first primary tooth eruption in infants. Cohort study with 43 preterm and 48 full-term infants aged at least four months. Infants were monitored monthly to verify the chronology of eruption of the first primary tooth. Mothers responded to sociodemographic and health behavior questionnaire. Principal Component Analysis and path analysis were performed. Two models were constructed: chronological and corrected age of tooth eruption. Model using chronological age of tooth eruption demonstrated that preterm infants had an increased risk of having later tooth eruption compared to those born at term ([β] = 0.888; p < 0.001). Indirect associations were found between socioeconomic and health conditions with the age of tooth eruption, mediated by gestational age. The same direct and indirect associations were also found for corrected age, with differences only in β values. It is concluded that preterm infants exhibited higher risk of delayed tooth eruption compared to full-term infants, considering both chronological and corrected age. Gestational age mediated the association between socioeconomic and health conditions with the age of tooth eruption. Full article

Aim: Early childhood caries (ECC) is a widespread and multifactorial oral disease that affects children globally. Parents’ knowledge, attitudes, and behaviors are crucial in preventing ECC and supporting oral health. This study evaluated Croatian parents’ understanding of children’s oral health, their awareness of ECC risk factors, and their oral hygiene practices. Materials and methods: A cross-sectional study was conducted using an anonymous and voluntary online questionnaire from October to December 2024 among 948 parents of children aged 1–7 years across Croatia. The study assessed parents’ knowledge of oral health, their understanding of the relationship between risk factors and early childhood caries, habits related to oral hygiene care, children’s experiences with oral health problems, parents’ self-assessment of their knowledge, as well as both their own and their children’s general and oral health and hygiene practices. Data were analyzed using descriptive statistics, Chi-square test, Mann–Whitney U test, and Kruskal–Wallis test. Results: Overall parental knowledge was moderate, with significantly higher scores among older parents, those with university education, healthcare workers, and families with higher incomes (p < 0.05). Parents demonstrated good awareness of the importance of supervising tooth brushing until age seven (93.8%) and fluoride use (81.8%); yet gaps persisted regarding bacterial transmission, tooth eruption, and early orthodontic evaluation. Preventive dental visits were frequently delayed, and only 25.0% of parents reported using interdental cleaning aids. Caries was the most common oral health issue among children (22.3%). Conclusions: Despite moderate awareness and some adherence to preventive measures, significant knowledge and practice gaps remain among Croatian parents. Targeted educational interventions and nationwide preventive strategies are necessary to strengthen oral health literacy and reduce ECC prevalence. Full article

Rima Bode is located on the central nearside of the Moon, with its rich volcanic landforms, which is considered an ideal region for studying lunar geological evolution. In this study, we systematically analyzed the geomorphological characteristics, composition, spatial thickness variations in basalts and pyroclastic deposits, thermophysical properties, and chronology of Rima Bode using the Kaguya Multiband (MI) data, Moon Mineralogy Mapper (M3) data, Terrain Camera (TC) data, and the CE-2 Microwave Radiometer (MRM) data. The main results are as follows. (1) The basalts can be categorized into three distinct units (Regions II, III, and IV), and the distribution range of pyroclastic deposits was redefined. Using the crater excavation technique, the deposit thicknesses were constrained to 4.3–51.9 m for pyroclastic deposits and 2.3–269.2 m for basalts, establishing a quantitative stratigraphic framework; (2) this study reveals that pyroclastic deposits exhibit abnormally brightness temperature (TB) behaviors, with slower diurnal TB change rates, indicating their high thermal inertia. (3) Chronological analysis indicated that volcanism lasted for ~0.38 Ga, with at least four distinct episodes of volcanic eruptions, suggesting complex magmatic processes and continued thermal activity within this region. These findings establish a comprehensive geological framework for the Rima Bode region, thereby deepening our understanding of its geological evolution. Full article

The increasing frequency of extreme wildfire behavior globally, particularly under the influence of anthropogenic climate change, poses unprecedented challenges to traditional fire management paradigms. This study presents a comprehensive, multi-dimensional case study of the catastrophic eruptive fire event that occurred in Xintian County, Hunan Province, China, on 17 October 2022. By integrating data on long-term ecological drought, critical synoptic-scale weather conditions, and real-time emission profiles of combustion products, we delineate the mechanistic chain leading to eruptive fire development in a subtropical evergreen broad-leaved forest region, historically considered a low-to-moderate fire risk zone. Our results demonstrate that the eruptive fire was a consequence of a critical convergence of factors: a protracted pre-conditioning drought that significantly reduced live and dead fuel moisture, a specific meteorological window characterized by extremely low relative humidity (<60%) and initially high wind speeds (peak at 16.5–17.9 m/s), and the abundant production and accumulation of flammable pyrolysis gases (e.g., CO, CH₄) from the dominant Masson pine forests. The emission data pinpointed October 19th as the key tipping point, marking the transition to high-intensity combustion. This study underscores the vulnerability of subtropical forest ecosystems to eruptive fires during compound extreme events. Our findings provide a critical scientific basis for updating fire danger rating systems and early warning strategies in similar ecological regions under a changing climate. Full article

Background/Objectives: The oral cavity has been discussed as a possible reservoir for pathogens involved in pediatric appendicitis. In a previous study, microbial similarities between oral and appendix samples were observed, but clinical dental findings showed no significant associations. The present study aimed to (1) perform a more detailed analysis of dental variables—such as eruption status, caries indices, oral hygiene behavior, and the Periodontal Screening Index (PSI)—to identify potential overlooked associations with appendicitis, and (2) compare two oral sampling sites (buccal mucosa and dental sulcus) in terms of their correlation with appendix microbiota. Methods: This secondary analysis used previously collected clinical and microbiological data from 36 children who had undergone appendectomy or elective surgery. Quantitative PCR (qPCR) was used to assess bacterial mRNA levels in appendix, buccal mucosa, and sulcus samples. Dental variables were derived from standardized clinical examinations performed at the time of surgery. Results: No significant group differences were observed in caries indices, PSI, or oral hygiene behavior. However, patients with appendicitis had a significantly higher number of erupting teeth compared to controls (3.82 vs. 1.68; p = 0.021). Bacterial mRNA levels did not differ notably between oral sites, and neither showed stronger correspondence with appendix samples; notably, sulcus swabs were not obtained from erupting teeth, limiting the ability to test a site-specific eruption mechanism. Conclusions: Tooth eruption may be associated with appendicitis, although this remains speculative and requires confirmation in larger studies. Full article