1,559 research outputs found
Positive solutions of transport equations and classical nonuniqueness of characteristic curves
The seminal work of DiPerna and Lions [Invent. Math., 98, 1989] guarantees
the existence and uniqueness of regular Lagrangian flows for Sobolev vector
fields. The latter is a suitable selection of trajectories of the related ODE
satisfying additional compressibility/semigroup properties. A long-standing
open question is whether the uniqueness of the regular Lagrangian flow is a
corollary of the uniqueness of the trajectory of the ODE for a.e. initial
datum. Using Ambrosio's superposition principle we relate the latter to the
uniqueness of positive solutions of the continuity equation and we then provide
a negative answer using tools introduced by Modena and Sz\'ekelyhidi in the
recent groundbreaking work [Ann. PDE, 4, 2018]. On the opposite side, we
introduce a new class of asymmetric Lusin-Lipschitz inequalities and use them
to prove the uniqueness of positive solutions of the continuity equation in an
integrability range which goes beyond the DiPerna-Lions theory
Integrating Safety-I and Safety-II Approaches in Near Miss Management: A Critical Analysis
Safety-II is a recently theorized approach, considering safety as the ability of a system to reach a positive outcome under variable conditions: analyzing “what goes right” can help to understand the dynamics of the analyzed system and improve its inherent safety level. On the contrary, a more traditional perspective, defined as Safety-I, aims at analyzing “what goes wrong”, thereby relating the safety level of a system to the number of adverse events that occurred. This study explores the potentialities of integrating these two approaches in near-miss management. Through a Safety-I approach, near-miss events are analyzed to identify the root causes generating the event
chain, in order to delete them and prevent future accidents. Applying a Safety-II approach, the analysis can include elements that contributed to limiting the consequences and blocking the event chain, revealing the resilience level of the systems. This study presents a critical analysis of the two approaches and proposes a practical framework to integrate them into near-miss management systems. A test case shows the potential benefits of this integration. This work provides a tool to support the implementation of Safety-II on the operative level while suggesting a new perspective for near-miss management
Onsager critical solutions of the forced Navier-Stokes equations
We answer positively to [BDL22, Question 2.4] by building new examples of solutions to the forced 3d-Navier-Stokes equations with vanishing viscosity, which exhibit anomalous dissipation and which enjoy uniform bounds in the space , for any fixed . Our construction combines ideas of [BDL22] and [CCS22]
A PRODUÇÃO ESCRITA NO LIVRO DIDÁTICO DE LÍNGUA ESPANHOLA
Resumo: Frente ao contemporâneo cenário brasileiro, em relação ao ensino de língua espanhola, o presente estudo tem como tema a produção escrita no livro didático de língua espanhola, em consonância ao Programa Nacional do Livro Didático – PNLD. Nesse sentido, problematiza-se: de que forma os Livros Didáticos de espanhol aprovados no Programa Nacional do Livro Didático 2015 contribuem para o desenvolvimento das habilidades necessárias à escrita em língua estrangeira? O objeto de estudo diz respeito às propostas de escrita das coleções de Espanhol aprovadas – Enlaces e Cercanía Joven. Objetiva-se, assim, analisar se os Livros Didáticos de espanhol aprovados no PNLD 2015 contribuem para o desenvolvimento das habilidades necessárias à escrita em língua espanhola. Para tanto, realizamos um trabalho de cunho descritivo, bibliográfico e de base qualitativa. Enquanto considerações finais, entende-se a necessidade de resistência cultural e docente a fim de que seja possível (re)existir frente ao cenário apresentado, bem como avalia-se que é preciso retomar o trabalho da escrita nas aulas de Língua Espanhola, com o apoio do livro didático.
Diversity and selection of wild food plants in six regions of Northwestern Iberian Peninsula (Spain and Portugal).
Resumo publicado de comunicação oral apresentada no painel Ethnobotanical Studies of Wild Plant Foods do IVth International Congress of EthnobotanyWe discuss and compare the traditional knowledge and use of wild edible plants in six rural regions of the northwest of the Iberian Peninsula. The data indicate that a high percentage of species are used in most regions (15 species are used in 5 regions). According to the similarity of the species gathered, the six regions can be grouped
in two clusters. Therefore, affinity seems to be linked to closeness. The Portuguese region is the most dissimilar due to a very high number and frequency of wild condiments
Updates on Children with Allergic Rhinitis and Asthma during the COVID‐19 Outbreak
Background: During the lockdown period caused by the SARS‐CoV‐2 pandemic, we monitored via online survey the trend of allergic symptoms and the therapeutic compliance in pa‐ tients followed at our center. Material and methods: In June 2020, we selected children followed at the Allergy and Immunology Service of Umberto I Hospital, aged between 6 and 16 years old, di‐ agnosed with asthma and/or rhinitis and sensitized to grass pollen or dust mite. We sent an email with 12 multiple‐choice questions investigating several areas: type of disease and sensitization, recurrence of symptoms, medication use during lockdown compared to the same period of the previous year. Results: The results of 82 questionnaires showed that 17.8% of patients suffered from asthma, 24.4% from rhinitis, and 57.8% from both. Within the group of asthmatic children, most of them presented an improvement of their symptoms. Likewise, with regard to allergic rhi‐ nitis, most of them reported better clinical conditions. Regarding treatment, we observed a global decrease in the use of on‐demand therapies (salbutamol, nasal corticosteroid, and antihistamine) for both pathologies. In addition, there was a reduction in the use of basal therapy for asthma and rhinitis from 2019 (23.3%) to 2020 (15.5%). Conclusions: Our data show a general trend of clinical improvement and a reduction in the use of on‐demand and basal therapy in allergic children during the lockdown
Literacy and metalinguistic development: a study with illiterate adults
This study was designed to investigate the role of literacy in metalinguistic development. Twenty-five adults (5 illiterate, 7 in an intermediate level of literacy and 13 in a advanced level) participated in this study. The adults were tested in several syntactic and phonological awareness tasks. Results of non-parametric Analysis of Variance showed that illiterate adults had overall worse performance than the literate ones. There was little difference between the literate groups. The results suggest that literacy have an effect in metalinguistic awareness development.Este estudo - com vinte e cinco adultos (5 não alfabetizados, 7 com nível de leitura intermediário e 13 com nível de leitura mais avançado) - foi delineado para investigar o papel da alfabetização no desenvolvimento da consciência metalingüística. Os adultos realizaram várias tarefas de consciência sintática e fonológica. Os resultados das análises de variância não paramétricas realizadas mostraram que os adultos não alfabetizados tiveram performances inferiores, em geral, a dos alfabetizados. No entanto pouca diferença foi encontrada entre os grupos de leitores. Os resultados sugerem que a alfabetização tem um efeito no desenvolvimento metalingüístico
Treatment of seizures in the neonate: guidelines and consensus-based recommendations—special report from the ILAE task force on neonatal seizures
Seizures are common in neonates, but there is substantial management variability. The Neonatal Task Force of the International League Against Epilepsy (ILAE) developed evidence-based recommendations about antiseizure medication (ASM) management in neonates in accordance with ILAE standards. Six priority questions were formulated, a systematic literature review and meta-analysis were performed, and results were reported following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) 2020 standards. Bias was evaluated using the Cochrane tool and risk of Bias in non-randomised studies - of interventions (ROBINS-I), and quality of evidence was evaluated using grading of recommendations, assessment, development and evaluation (GRADE). If insufficient evidence was available, then expert opinion was sought using Delphi consensus methodology. The strength of recommendations was defined according to the ILAE Clinical Practice Guidelines development tool. There were six main recommendations. First, phenobarbital should be the first-line ASM (evidence-based recommendation) regardless of etiology (expert agreement), unless channelopathy is likely the cause for seizures (e.g., due to family history), in which case phenytoin or carbamazepine should be used. Second, among neonates with seizures not responding to first-line ASM, phenytoin, levetiracetam, midazolam, or lidocaine may be used as a second-line ASM (expert agreement). In neonates with cardiac disorders, levetiracetam may be the preferred second-line ASM (expert agreement). Third, following cessation of acute provoked seizures without evidence for neonatal-onset epilepsy, ASMs should be discontinued before discharge home, regardless of magnetic resonance imaging or electroencephalographic findings (expert agreement). Fourth, therapeutic hypothermia may reduce seizure burden in neonates with hypoxic–ischemic encephalopathy (evidence-based recommendation). Fifth, treating neonatal seizures (including electrographic-only seizures) to achieve a lower seizure burden may be associated with improved outcome (expert agreement). Sixth, a trial of pyridoxine may be attempted in neonates presenting with clinical features of vitamin B6-dependent epilepsy and seizures unresponsive to second-line ASM (expert agreement). Additional considerations include a standardized pathway for the management of neonatal seizures in each neonatal unit and informing parents/guardians about the diagnosis of seizures and initial treatment option
ZAP-70 expression in acute lymphoblastic leukemia: association with the E2A/PBX1 rearrangement and the pre-B stage of differentiation and prognostic implications
We evaluated the expression of 2 members of the Syk family, ZAP-70 and Syk, in acute lymphoblastic leukemia (ALL) samples, using data derived from a series of 33 T-ALL and 95 B-lineage adult ALL patients analyzed by oligonucleotide arrays. Of the B-lineage ALL cases, 37 were BCR/ABL+, 10 were ALL1/AF4+, 5 were E2A/PBX1+, and 43 carried no known molecular abnormality. ZAP-70 was highly expressed in T-ALL. A high ZAP-70 expression was also found in a proportion of B-lineage ALL, the highest levels being associated with the E2A/PBX1+ group and the lowest with ALL1/AF4+ cases (P < .001). A higher ZAP-70 expression was also observed in the pre-B group (P < .001). Remarkably, Syk expression was always preserved, suggesting that ZAP-70 expression is not substitutive of Syk. At the protein level, ZAP-70 was evaluated on 39 newly diagnosed ALL patients (25 adults, 14 children) and was detected in 23 cases (59%). ZAP-70 expression was consistently found in Ig mu+ cases. Evaluation of long-term outcome in cases without molecular abnormalities showed that the higher levels of ZAP-70 were coupled to a higher relapse rate. In ALL, ZAP-70 expression is associated with the E2A/PBX1 rearrangement and pre-B stage and may have a prognostic role and be a candidate molecule for targeted therapies
Pharmacokinetics of Echinocandins in Suspected Candida Peritonitis: a Potential Risk for Resistance.
A possible increase of Candida resistance, specially in C. glabrata, has been speculated according to a poor diffusion of echinocandins to peritoneal fluid.
Peritoneal and serum concentrations of Caspofungin, micafungin and anidulafungin were analyzed in surgical patients with suspected candida peritonitis. After four days of starting therapy serum and peritoneal samples (through peritoneal drainage) were obtained at baseline, 1 h, 6 h, 12 h, and 24 h of drug administration. Micafungin and anidulafungin concentrations were determined using high-performance liquid chromatography (HPLC/F), whereas caspofungin concentration were stablished by bioassay.
A total of 23 critically ill patients with suspected abdominal fungal infection who were receiving an echinocandin were prospectively recruited. No specific criteria were applied to prescribe one specific echinocadin. No special clinical differences were observed among the 3 groups of patients. All were receiving antibiotic therapy, 80% required inotropic drugs and finally fungal peritonitis were confirmed in 74% of them. The AUC0_24h (mg*h/L) obtained in serum and peritoneal fluid were: 126.84 and 34.38; 98.52 and 18.83; and 66.9 and 8.78 for anidulafungin, micafungin and caspofungin, respectively. The median concentration in peritoneal fluid ranged from 0.66 to 1.82 μg/ml for anidulafungin, 0.68 to 0.88 μg/mL for micafungin and 0.21 to 0.46 μg/ml for caspofungin.
The results show a moderate penetration of echinocandins into the peritoneal fluid in these patients. These levels are below the threshold of resistance mutant selection published by other authors. It could justify a potential risk of resistance in patients with prolonged treatments with echinocandins and suboptimal control of the abdominal infection.The study received funding from the “Fondo de Investigaciones Sanitarias” of the Spanish Ministry of Health (FIS PI 15/1536). The work was supported by Plan Nacional de I + D+i 2013-2016 and Instituto de Salud Carlos III, Subdirección General de Redes y Centros de Investigación Cooperativa, Ministerio de Ciencia, Innovación y Universidades, Spanish Network for Research in Infectious Diseases (REIPI RD16), and co-financed by European Development Regional Fund “A way to achieve Europe”, Operative program Intelligent Growth 2014-2020.S
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