26 research outputs found
Solar and Interplanetary Turbulence: Lagrangian Coherent Structures
Talk delivered in 22nd EGU General Assembly, held online 4-8 May, 2020, id.4289, https://meetingorganizer.copernicus.org/EGU2020/EGU2020-4289.html.-- https://www.egu2020.eu/The dynamics of solar and interplanetary plasmas is governed by coherent structures such as current sheets and magnetic flux ropes which are responsible for the genesis of intermittent turbulence via magnetic reconnections in solar supergranular junctions, solar coronal loops, the shock-sheath region of an interplanetary coronal mass ejection, and the interface region of two interplanetary magnetic flux ropes. Lagrangian coherent structures provide a new powerful technique to detect time- or space-dependent transport barriers, and objective (i.e., frame invariant) kinematic and magnetic vortices in space plasma turbulence. We discuss the basic concepts of Lagrangian coherent structures in plasmas based on the computation of the finite-time Lyapunov exponent, the Lagrangian averaged vorticity deviation and the integrated averaged current deviation, as well as their applications to numerical simulations of MHD turbulence and space and ground observations.With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation SEV-2017-070
ISOLATION AND GENOTYPING OF Toxoplasma gondii IN SERONEGATIVE URBAN RATS AND PRESENCE OF ANTIBODIES IN COMMUNICATING DOGS IN BRAZIL
Adaptive timing of motor output in the mouse: the role of movement oscillations in eyelid conditioning
To survive, animals must learn to control their movements with millisecond-level precision, and adjust the kinematics if conditions, or task requirements, change. Here, we examine adaptive timing of motor output in mice, using a simple eyelid conditioning task. Mice were trained to blink in response to a light stimulus that was always followed by a corneal air-puff at a constant time interval. Different mice were trained with different intervals of time separating the onset of the light and the air-puff. As in previous work in other animal species, mice learned to control the speed of the blink, such that maximum eyelid closure occurred at the interval used during training. Despite this, we found that maximum eyelid speed always occurred in the first 100 ms of the movement, indicating that speed is not uniformly adjusted throughout the duration of the blink. A new analysis, specifically designed to examine the kinematics of blinks in single trials, revealed the nature of the underlying control signal: the learned blinks are made up of oscillatory eyelid movements that are time-locked to the light stimulus at the beginning of the blink, becoming desynchronized later on. Furthermore, mice learn to blink at different speeds and time the movement appropriately by adjusting the amplitude, but not the frequency of the underlying eyelid oscillation
LT for CRLM should be employed under investigational protocols through clinical trials
Adenocarcinoma of the colon and rectum (CRC) is the second leading cause of cancer mortality, driven by stage IV disease [1]. While surgical resection of liver metastases has demonstrated a survival advantage, a minority of patients are candidates for resection due to anatomic involvement of disease. Recent advances in liver surgery, chemotherapy, and decision making guided by stratification at the time of presentation has better equipped us to perform aggressive metastasectomies, with resulting improved survival [2-4]. As a result, there is a resurgent interest in the concept of total hepatectomy and liver transplantation (LT) for colorectal liver metastases (CRLM). As of this writing, eight prospective clinical trials in six countries are assessing the viability of split or whole LT for CRLM. However, LT for CRLM remains controversial. Recent prospective trials have illustrated the importance of patient selection, and a disciplined respect for tumor biology. Here we present the current status of LT for CRLM, and suggest clinical decision criteria aimed at matching survival benefit comparable to other indications for LT
Comparison of the indirect fluorescent antibody test and modified agglutination test for detection of anti-Toxoplasma gondii antibodies in rats / <br> Comparação da reação de imunofluorescência indireta e do teste de aglutinação modificado na detecção de anticorpos anti-Toxoplasma gondii em ratos
The toxoplasmosis is a zoonosis caused by Toxoplasma gondii and affects a lot of species of carnivores and omnivores, including the human. The rodents are important in the transmition cycle because they act as an infection font to felines, the definitive host of this protozoan. The objective of this work was to evaluate the Modified Agglutination Test (MAT) for the serologic diagnosis of toxoplasmosis in rats, comparing with the Indirect Fluorescent Antibody Test (IFAT), which has been considered the golden standard in animal toxoplasmosis diagnosis. Kappa test was used for comparing the serologic tests (IFAT and MAT) and for determination of cutoff appropriate to MAT in this animal species. 182 rats were caught on local recycling of solid waste and solid residue storage in Londrina city, Paraná. Out of the 182 rats, nine (4.94%) were positive to IFAT at a dilution of 1:16, and 17 (9.34%) and five (2.75%) were reactive to MAT in dilutions 1:25 and 1:50, respectively. The comparison of results between the techniques presented kappa coefficients of 0.26 and 0.55, respectively at 1:25 and 1:50 dilutions of MAT. It can be concluded that the dilution 1:50 is the most suitable to be used as cutoff for detecting T. gondii antibodies in rats using MAT, because agreed with IFAT.<p><p>A toxoplasmose é uma zoonose causada pelo Toxoplasma gondii que acomete várias espécies carnÃvoras e onÃvoras, incluindo o ser humano. Os roedores são importantes na cadeia epidemiológica da doença por servirem de fonte de infecção aos felÃdeos, os hospedeiros definitivos deste protozoário. O objetivo deste trabalho foi avaliar o Teste de Aglutinação Modificada (MAT) na detecção de anticorpos contra T. gondii em ratos, comparando-o à Reação de Imunofluorescência Indireta (RIFI), considerada padrão ouro para o diagnóstico da toxoplasmose animal. Empregou-se o teste kappa para a comparação dos testes sorológicos (RIFI e MAT) e para a determinação do ponto de corte mais apropriado para a utilização do MAT, nesta espécie animal. Foram capturados 182 ratos em locais de reciclagem e armazenagem de resÃduos sólidos na cidade de Londrina, PR. Destes, nove (4,94%) foram positivos na RIFI na diluição 1:16; e 17 (9,34%) e cinco (2,75%) foram sororreagentes ao MAT nas diluições 1:25 e 1:50, respectivamente. A comparação dos resultados entre as técnicas apresentou coeficientes kappa de 0,26 e 0,55, respectivamente à s diluições 1:25 e 1:50 do MAT. Conclui-se que a diluição 1:50 é a mais indicada para ser o ponto de corte na detecção de anticorpos contra T. gondii em ratos pelo MAT, por apresentar melhor concordância à RIFI
Implementation of a gastrostomy care bundle reduces dislodgements and length of stay
PURPOSE: Pediatric gastrostomy tubes (G-tubes) are associated with considerable utilization of healthcare resources. G-tube dislodgement can result in tract disruption and abdominal sepsis. We aimed to reduce early G-tube dislodgement by 25%. METHODS: An interdisciplinary team convened to identify key drivers of G-tube dislodgement and implement initiatives to reduce this complication. A G-tube care bundle was implemented in 2018. Rates of early G-tube dislodgement (within 90 days of insertion) were tracked. 15 months of cases after bundle implementation were compared to 20 months of cases before implementation. Length of stay (LOS, balancing measure) and bundle compliance (process measure) were tracked. RESULTS: G-tube dislodgements decreased 47% after bundle implementation. Overall, dislodgements after G-tube insertion decreased from 43% to 19% dislodgements per tube inserted, p = 0.004. Reductions were observed for dislodgements occurring in both the inpatient (14% vs. 1.5%) and outpatient (29% vs. 18%) settings. Median LOS was reduced from 15.3 to 7.1 days following implementation, p = 0.004. Process measures demonstrated 75% or greater compliance one year after implementation. CONCLUSION: An interdisciplinary team using quality improvement science methodology can significantly reduce G-tube dislodgement and improve value after pediatric gastrostomy tube insertion. TYPE OF STUDY: Longitudinal cohort study. LEVEL OF EVIDENCE: III
Emergency department utilization following pediatric gastrostomy tube placement is driven by a small cohort of patients
PURPOSE: Pediatric gastrostomy tubes (G-tubes) are associated with frequent postoperative problems and consumption of healthcare resources. We hypothesized that a small cohort of patients disproportionately drives healthcare resource utilization after G-tube insertion. This study aimed to characterize this population in order to implement evidence-based pathways to reduce healthcare utilization after G-tube insertion. METHODS: All surgically placed pediatric G-tubes at a quaternary care center between March 2011 and June 2018 were retrospectively reviewed. Healthcare utilization including radiographic studies, emergency department (ED) visits, hospital admissions, procedures, and diagnoses was abstracted. Encounter specific charges based on CPT codes were collected. Statistical analyses were performed with Mann Whitney U, Fisher\u27s Exact Test, and multivariate nominal logistic regression. Institutional review board approval was obtained. RESULTS: During the study period, 189 patients underwent G-tube insertion; 24% of patients presented to the ED two or more times and accounted for 82% of ED visits. This cohort of high ED utilizers was more likely to present with G-tube dislodgement [both within the first three months (early) and after three months (late)], required more radiographic studies, and accrued significantly more charges compared to low ED utilizers. Multivariate analyses demonstrated high ED utilization was significantly associated with non-Caucasian race and the surgeon performing the procedure. CONCLUSIONS: At our institution, a significant proportion of healthcare utilization following G-tube placement is consumed by a relatively small cohort of children. Future efforts will target patients with two or more G-tube related ED visits or an early G-tube dislodgement for additional education and integration with outpatient resources. TYPE OF STUDY: Retrospective study. LEVEL OF EVIDENCE: Level II
Leishmania in synanthropic rodents (Rattus rattus): new evidence for the urbanization of Leishmania (Leishmania) amazonensis
Abstract This study aimed to detect parasites from Leishmania genus, to determine the prevalence of anti-Leishmania spp. antibodies, to identify circulating species of the parasite, and to determine epidemiological variables associated with infection in rats caught in urban area of Londrina, Paraná, Brazil. Animal capture was carried out from May to December 2006, serological and molecular methods were performed. DNA was extracted from total blood, and nested-PCR, targeting SSu rRNA from Leishmania genus, was performed in triplicate. The positive samples were sequenced twice by Sanger method to species determination. In total, 181 rodents were captured, all were identified as Rattus rattus and none showed clinical alterations. Forty-one of the 176 (23.3%) animals were positive for Leishmania by ELISA and 6/181 (3.3%) were positive by IFAT. Nine of 127 tested animals (7.1%) were positive by PCR; seven were identified as L. (L.) amazonensis, one as L. (L.) infantum. Four rats were positive using more than one test. This was the first description of synanthropic rodents naturally infected by L. (L.) amazonensis (in the world) and by L. (L.) infantum (in South Brazil). Regarding L. (L.) amazonensis, this finding provides new evidence of the urbanization of this etiological agent