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Proximal (<3 km) deposits from episodes II and III of the 60-h-long Novarupta 1912 eruption exhibit a very complex stratigraphy, the result of at least four transport regimes and diverse depositional mechanisms. They contrast with the relatively simple stratigraphy (and inferred emplacement mechanisms) for the previously documented, better known, medial?distal fall deposits and the Valley of Ten Thousand Smokes ignimbrite. The proximal products include alternations and mixtures of both locally and regionally dispersed fall ejecta, and numerous thin complex deposits of pyroclastic density currents (PDCs) with no regional analogs. The locally dispersed component of the fall deposits forms sector-confined wedges of material whose thicknesses halve radially from and concentrically about the vent over distances of 100?300 m (cf. several kilometers for the medial?distal fall deposits). This locally dispersed fall material (and many of the associated PDC deposits) is rich in andesitic and banded pumices and richer in shallow-derived wall-rock lithics in comparison with the coeval medial fall units of almost entirely dacitic composition. There are no marked contrasts in grain size in the near-vent deposits, however, between locally and widely dispersed beds, and all samples of the proximal fall deposits plot as a simple continuation of grain size trends for medial?distal samples. Associated PDC deposits form a spectrum of facies from fines-poor, avalanched beds through thin-bedded, landscape-mantling beds to channelized lobes of pumice-block-rich ignimbrite. The origins of the Novarupta near-vent deposits are considered within a spectrum of four transport regimes: (1) sustained buoyant plume, (2) fountaining with co-current flow, (3) fountaining with counter-current flow, and (4) direct lateral ejection. The Novarupta deposits suggest a model where buoyant, stable, regime-1 plumes characterized most of episodes II and III, but were accompanied by transient and variable partitioning of clasts into the other three regimes. Only one short period of vent blockage and cessation of the Plinian plume occurred, separating episodes II and III, which was followed by a single PDC interpreted as an overpressured "blast" involving direct lateral ejection. In contrast, regimes 2 and 3 were reflected by spasmodic sedimentation from the margins of the jet and perhaps lower plume, which were being strongly affected by short-lived instabilities. These instabilities in turn are inferred to be associated with heterogeneities in the mixture of gas and pyroclasts emerging from the vent. Of the parameters that control explosive eruptive behavior, only such sudden and asymmetrical changes in the particle concentration could operate on time scales sufficiently short to explain the rapid changes in the proximal 1912 products. [ABSTRACT FROM AUTHOR]

Background: Machine learning uses algorithms that improve automatically through experience. This statistical learning approach is a natural extension of traditional statistical methods and can offer potential advantages for certain problems. The feasibility of using machine learning techniques in health care is predicated on access to a sufficient volume of data in a problem space., Objective: This study aimed to assess the feasibility of data collection from an adolescent population before and after a posterior spine fusion operation., Methods: Both physical and psychosocial data were collected. Adolescents scheduled for a posterior spine fusion operation were approached when they were scheduled for the surgery. The study collected repeated measures of patient data, including at least 2 weeks prior to the operation and 6 months after the patients were discharged from the hospital. Patients were provided with a Fitbit Charge 4 (consumer-grade health tracker) and instructed to wear it as often as possible. A third-party web-based portal was used to collect and store the Fitbit data, and patients were trained on how to download and sync their personal device data on step counts, sleep time, and heart rate onto the web-based portal. Demographic and physiologic data recorded in the electronic medical record were retrieved from the hospital data warehouse. We evaluated changes in the patients' psychological profile over time using several validated questionnaires (ie, Pain Catastrophizing Scale, Patient Health Questionnaire, Generalized Anxiety Disorder Scale, and Pediatric Quality of Life Inventory). Questionnaires were administered to patients using Qualtrics software. Patients received the questionnaire prior to and during the hospitalization and again at 3 and 6 months postsurgery. We administered paper-based questionnaires for the self-report of daily pain scores and the use of analgesic medications., Results: There were several challenges to data collection from the study population. Only 38% (32/84) of the patients we approached met eligibility criteria, and 50% (16/32) of the enrolled patients dropped out during the follow-up period-on average 17.6 weeks into the study. Of those who completed the study, 69% (9/13) reliably wore the Fitbit and downloaded data into the web-based portal. These patients also had a high response rate to the psychosocial surveys. However, none of the patients who finished the study completed the paper-based pain diary. There were no difficulties accessing the demographic and clinical data stored in the hospital data warehouse., Conclusions: This study identifies several challenges to long-term medical follow-up in adolescents, including willingness to participate in these types of studies and compliance with the various data collection approaches. Several of these challenges-insufficient incentives and personal contact between researchers and patients-should be addressed in future studies., (©Giovanni Cucchiaro, Luis Ahumada, Geoffrey Gray, Jamie Fierstein, Hannah Yates, Kym Householder, William Frye, Mohamed Rehman. Originally published in JMIR Formative Research (https://formative.jmir.org), 15.08.2022.)

Objective: Self-efficacy is the personal belief that a behavior can produce a desired result; and in asthma, self-efficacy in asthma care has been related to improvements in asthma outcomes and children's quality of life. To appreciate the full burden of asthma on families, the relationship between parental self-efficacy and quality of life also needs further study. We aim to characterize this relationship. Methods: Secondary analysis of measurements of parents of children with persistent asthma ( n  = 252; ages 4-17 years) from a large urban area were identified from a randomized trial; the association between baseline assessments of parental quality of life, measured by the Pediatric Asthma Caregiver's Quality of Life Questionnaire (PACQLQ), and parental self-efficacy, measured through the Parental Asthma Management Self-Efficacy Scale (PAMSES), were examined through multivariable linear regression. Results: Parental self-efficacy in asthma was positively associated with quality of life among parents of racially and ethnically diverse children ( p  = 0.01). Confidence in using medications correctly ( p  = 0.03), having inhalers during a child's serious breathing problem ( p  = 0.02), and knowing which medications to use during a child's serious breathing problem ( p  = 0.04) were associated with a clinically meaningful difference in parental quality of life. Other significant factors associated with parental quality of life included Hispanic/Latino ethnicity ( p  < 0.01) of the child and Asthma Control Test scores ( p  < 0.01). Conclusion: The findings suggest that improving parental confidence on when and how to use their child's asthma medications, particularly during an asthma attack, might be clinically meaningful in enhancing parent's quality of life.

Seventy-seven patients with glomus tumors involving the temporal bone were treated by surgery, irradiation, and combined therapy. The therapeutic success rate for the surgery group was 91 percent for glomus tympanicum and 78 percent for glomus jugulare tumors. The success rate for radiation therapy was 30% in glomus jugulare tumors. Patients with extensive lesions treated by combined therapy had a therapeutic success rate of 60 percent. The clinical response of glomus jugulare tumors to radiation therapy was 65 percent. Surgery appears to be the best method for eradication of the tumors; however, with large extensive lesions, combined therapy offers a better prognosis than either modality alone.

Selective delivery of low-dose streptokinase was effective in the treatment of embolic occlusion of the celiac and superior mesenteric arteries. The two-catheter technique resulted in complete lysis of clot in the celiac artery and improvement in patency of the superior mesenteric artery. The procedure restored effective mesenteric blood flow and provided an alternative to surgery in a very ill patient.

Medullary carcinoma is an unusual malignant neoplasm. The cell of origin is considered to be the C-cell which is derived from the ultimobranchial body and neural crest. The tumor is solid and has characteristic amyloid in the stroma. The lesion usually presents as a neck mass, and multicentricity is not unusual. In some patients diarrhea may be an important presenting symptom. Serum calcitonin is typically elevated and is important in the diagnostic confirmation. About 10 percent of the cases are part of a familial endocrine syndrome which includes pheochromocytomas, mucosal neuromas, and other endocrine gland adenomas. Frequent multicentricity and early cervical lymphatic and systemic metastases necessitate total thyroidectomy and radical neck dissection. Prognosis varies from a rapid demise to long term survival.