179 research outputs found
Floquet scalar dynamics in global AdS
We study periodically driven scalar fields and the resulting geometries with global AdS asymptotics. These solutions describe the strongly coupled dynamics of dual finite-size quantum systems under a periodic driving which we interpret as Floquet condensates. They span a continuous two-parameter space that extends the linearized solutions on AdS. We map the regions of stability in the solution space. In a significant portion of the unstable subspace, two very different endpoints are reached depending upon the sign of the perturbation. Collapse into a black hole occurs for one sign. For the opposite sign instead one attains a regular solution with periodic modulation. We also construct quenches where the driving frequency and amplitude are continuously varied. Quasistatic quenches can interpolate between pure AdS and sourced solutions with time periodic vev. By suitably choosing the quasistatic path one can obtain boson stars dual to Floquet condensates at zero driving field. We characterize the adiabaticity of the quenching processes. Besides, we speculate on the possible connections of this framework with time crystals.This work of was supported by grants FPA2014-52218-P from Ministerio de Economia
y Competitividad, by Xunta de Galicia ED431C 2017/07, by FEDER and by Grant
Mar a de Maeztu Unit of Excellence MDM-2016-0692. A.S. is happy to acknowledge support
from the International Centre for Theoretical Sciences (ICTS-TIFR), and wants to
express his gratitude to the ICTS community, and especially to the String Theory Group,
for their warm welcome. D.M. thanks the FRont Of pro-Galician Scientists (FROGS) for
unconditional support. A.B. thanks the support of the Spanish program \Ayudas para contratos
predoctorales para la formaci on de doctores 2015" associated to FPA2014-52218-P.
This research has benefited from the use computational resources/services provided by the
Galician Supercomputing Centre (CESGA).S
Effects of a Brazilian cardioprotective diet and nuts on cardiometabolic parameters after myocardial infarction : study protocol for a randomized controlled clinical trial
Background Nut consumption has been related to improvements on cardiometabolic parameters and reduction in the severity of atherosclerosis mainly in primary cardiovascular prevention. The objective of this trial is to evaluate the effects of the Brazilian Cardioprotective Diet (DIeta CArdioprotetora Brasileira, DICA Br) based on consumption of inexpensive locally accessible foods supplemented or not with mixed nuts on cardiometabolic features in patients with previous myocardial infarction (MI). Methods DICA-NUTS study is a national, multicenter, randomized 16-week follow-up clinical trial. Patients over 40 years old with diagnosis of previous MI in the last 2 to 6 months will be recruited (n = 388). A standardized questionnaire will be applied to data collection and blood samples will be obtained. Patients will be allocated in two groups: Group 1: DICA Br supplemented with 30 g/day of mixed nuts (10 g of peanuts, 10 g of cashew, 10 g of Brazil nuts); and Group 2: only DICA Br. The primary outcome will consist of LDL cholesterol means (in mg/dL) after 16 weeks of intervention. Secondary outcomes will consist of other markers of lipid profile, glycemic profile, and anthropometric data. Discussion It is expected that DICA Br supplemented with mixed nuts have superior beneficial effects on cardiometabolic parameters in patients after a MI, when compared to DICA Br. Trial registration ClinicalTrials.gov Identifier NCT03728127. First register: November 1, 2018; Last update: June 16, 2021. World Health Organization Universal Trial Number (WHO-UTN): U1111-1259-8105
ATIVIDADE ANTIMICROBIANA DO ÓLEO ESSENCIAL DA MENTHA X VILLOSA HUDS
As propriedades farmacêuticas encontradas nas plantas medicinas são obtidasa partir de suas substâncias secundárias, entre elas, estão os óleos voláteis. Um fatorrelevante no estudo de óleos essenciais, é sua constituição química na planta, a qual évariável conforme o período do dia. Objetivou-se nesse trabalho, avaliar a atividadeantimicrobiana do óleo essencial da espécie Mentha x villosa Huds (hortelã rasteira) emextrações circadianas. As avaliações das atividades antimicrobianas foram realizadasatravés da determinação da técnica de Concentração Inibitória Mínima (CIM) eConcentração Letal Mínima (CLM). Verificou-se que os óleos foram ativos contra todosos microrganismos testados. Destaca-se que houve pequenas variações nos resultados,por conta das coletas circadianas. Sugere-se que as variações observadas no decurso dasatividades antimicrobianas possam estar relacionadas à composição química dos óleosnos diferentes horários de coletas
A DNA Tool for the Identification of Heavily Exploited Atlantic Billfishes
Due to the morphological similarities among species, the International Commission for the Conservation of the Atlantic Tunas has recommended the use of diagnostic molecular tools to allow for robust species-level identifications of the billfishes. In this study, a protocol for the molecular identification of all six Atlantic billfishes was developed utilizing a PCR–RFLP approach, targeting the mitochondrial gene cytochrome c oxidase subunit 1. A survey of 28 restriction endonucleases identified two enzymes (TaqI and HaeIII) that produced species-specific banding patterns sufficient to distinguish species. The protocol was validated against billfishes captured across their Atlantic distributions
Round multiprofissional com checklist: associação com a melhoria na segurança do paciente em terapia intensiva
Objetivo: Verificar a associação entre round multiprofissional com uso de checklist e práticas de segurança do paciente por profissionais de saúde de uma unidade de terapia intensiva.Método: Estudo de método misto, delineado pela abordagem sequencial explanatória, realizado em um hospital do sul do Brasil. Os dados quantitativos foram analisados por meio de regressão de Poisson e os dados qualitativos, pela análise de conteúdo. Fez-se a análise integrada por meio da combinação explicada/conectada.Resultados: No período pós-implementação dos rounds com uso sistemático de checklist houve melhora significativa da profilaxia de tromboembolia venosa, sedação leve, redução dos dias de uso de ventilação mecânica, cateter venoso central e de sonda vesical de demora.Conclusão: O round multiprofissional com uso sistemático de checklist, associado com a melhoria nas práticas de segurança do paciente, foi considerado como uma estratégia que assegura melhores cuidados em terapia intensiva e favorece a satisfação no trabalho.
Palavras-chave: Lista de checagem. Visitas com preceptor. Unidades de terapia intensiva. Segurança do paciente. Equipe de assistência ao paciente
Early administration of fibrinogen concentrate in patients with polytrauma with thromboelastometry suggestive of hypofibrinogenemia: A randomized feasibility trial
OBJECTIVE: To evaluate the clinical effects of early administration of fibrinogen concentrate in patients with severe trauma and hypofibrinogenemia.
METHODS: We conducted an open randomized feasibility trial between December 2015 and January 2017 in patients with severe trauma admitted to the emergency department of a large trauma center. Patients presented with hypotension, tachycardia, and FIBTEM findings suggestive of hypofibrinogenemia. The intervention group received fibrinogen concentrate (50 mg/kg), and the control group did not receive early fibrinogen replacement. The primary outcome was feasibility assessed as the proportion of patients receiving the allocated treatment within 60 min after randomization. The secondary outcomes were transfusion requirements and other exploratory outcomes. Randomization was performed using sequentially numbered and sealed opaque envelopes. ClinicalTrials.gov: NCT02864875.
RESULTS: Thirty-two patients were randomized (16 in each group). All patients received the allocated treatment within 60 min after randomization (100%, 95% confidence interval, 86.7%-100%). The median length of intensive care unit stay was shorter in the intervention group (8 days, interquartile range [IQR] 5.75-10.0 vs. 11 days, IQR 8.5-16.0; p=0.02). There was no difference between the groups in other clinical outcomes. No adverse effects related to treatment were recorded in either group.
CONCLUSION: Early fibrinogen replacement with fibrinogen concentrate was feasible. Larger trials are required to properly evaluate clinical outcomes
Replacement of fentanyl infusion by enteral methadone decreases the weaning time from mechanical ventilation: a randomized controlled trial
Introduction: Patients undergoing mechanical ventilation (MV) are frequently administered prolonged and/or high doses of opioids which when removed can cause a withdrawal syndrome and difficulty in weaning from MV. We tested the hypothesis that the introduction of enteral methadone during weaning from sedation and analgesia in critically ill adult patients on MV would decrease the weaning time from MV. Methods: A double-blind randomized controlled trial was conducted in the adult intensive care units (ICUs) of four general hospitals in Brazil. The 75 patients, who met the criteria for weaning from MV and had been using fentanyl for more than five consecutive days, were randomized to the methadone (MG) or control group (CG). Within the first 24 hours after study enrollment, both groups received 80% of the original dose of fentanyl, the MG received enteral methadone and the CG received an enteral placebo. After the first 24 hours, the MG received an intravenous (IV) saline solution (placebo), while the CG received IV fentanyl. For both groups, the IV solution was reduced by 20% every 24 hours. The groups were compared by evaluating the MV weaning time and the duration of MV, as well as the ICU stay and the hospital stay. Results: Of the 75 patients randomized, seven were excluded and 68 were analyzed: 37 from the MG and 31 from the CG. There was a higher probability of early extubation in the MG, but the difference was not significant (hazard ratio: 1.52 (95% confidence interval (CI) 0.87 to 2.64; P = 0.11). The probability of successful weaning by the fifth day was significantly higher in the MG (hazard ratio: 2.64 (95% CI: 1.22 to 5.69; P < 0.02). Among the 54 patients who were successfully weaned (29 from the MG and 25 from the CG), the MV weaning time was significantly lower in the MG (hazard ratio: 2.06; 95% CI 1.17 to 3.63; P < 0.004). Conclusions: The introduction of enteral methadone during weaning from sedation and analgesia in mechanically ventilated patients resulted in a decrease in the weaning time from MV
Immunomodulators for immunocompromised patients hospitalized for COVID-19: a meta-analysis of randomized controlled trials
BACKGROUND: Although immunomodulators have established benefit against the new coronavirus disease (COVID-19) in general, it is uncertain whether such agents improve outcomes without increasing the risk of secondary infections in the specific subgroup of previously immunocompromised patients. We assessed the effect of immunomodulators on outcomes of immunocompromised patients hospitalized for COVID-19.METHODS: The protocol was prospectively registered with PROSPERO (CRD42022335397). MEDLINE, Cochrane Central Register of Controlled Trials and references of relevant articles were searched up to 01-06-2022. Authors of potentially eligible randomized controlled trials were contacted to provide data on immunocompromised patients randomized to immunomodulators vs control (i.e., placebo or standard-of-care).FINDINGS: Eleven randomized controlled trials involving 397 immunocompromised patients hospitalized for COVID-19 were included. Ten trials had low risk of bias. There was no difference between immunocompromised patients randomized to immunomodulators vs control regarding mortality [30/182 (16.5%) vs 41/215 (19.1%); RR 0.93, 95% CI 0.61-1.41; p = 0.74], secondary infections (RR 1.00, 95% CI 0.64-1.58; p = 0.99) and change in World Health Organization ordinal scale from baseline to day 15 (weighed mean difference 0.27, 95% CI -0.09-0.63; p = 0.15). In subgroup analyses including only patients with hematologic malignancy, only trials with low risk of bias, only trials administering IL-6 inhibitors, or only trials administering immunosuppressants, there was no difference between comparators regarding mortality.INTERPRETATION: Immunomodulators, compared to control, were not associated with harmful or beneficial outcomes, including mortality, secondary infections, and change in ordinal scale, when administered to immunocompromised patients hospitalized for COVID-19.FUNDING: Hellenic Foundation for Research and Innovation.</p
Early goal-directed therapy using a physiological holistic view: the ANDROMEDA-SHOCK—a randomized controlled trial
Septic shock is a highly lethal condition. Early recognition of tissue hypoperfusion and its reversion
are key factors for limiting progression to multiple organ dysfunction and death. Lactate‐targeted resuscitation is the gold‐standard under current guidelines, although it has several pitfalls including that non‐hypoxic sources of lactate might predominate in an unknown proportion of patients. Peripheral perfusion‐targeted resuscitation might provide a real‐time response to increases in ow that could lead to a more timely decision to stop resuscitation, thus avoiding uid overload and the risks of over‐resuscitation. This article reports the rationale, study design and analysis plan of the ANDROMEDA‐SHOCK Study.
Methods: ANDROMEDA‐SHOCK is a randomized controlled trial which aims to determine if a peripheral perfusion‐ targeted resuscitation is associated with lower 28‐day mortality compared to a lactate‐targeted resuscitation in patients with septic shock with less than 4 h of diagnosis. Both groups will be treated with the same sequential approach during the 8‐hour study period pursuing normalization of capillary re ll time versus normalization or a decrease of more than 20% of lactate every 2 h. The common protocol starts with uid responsiveness assessment and uid loading in responders, followed by a vasopressor and an inodilator test if necessary. The primary outcome
is 28‐day mortality, and the secondary outcomes are: free days of mechanical ventilation, renal replacement therapy and vasopressor support during the rst 28 days after randomization; multiple organ dysfunction during the rst 72 h after randomization; intensive care unit and hospital lengths of stay; and all‐cause mortality at 90‐day. A sample size of 422 patients was calculated to detect a 15% absolute reduction in mortality in the peripheral perfusion group with 90% power and two‐tailed type I error of 5%. All analysis will follow the intention‐to‐treat principle.
Conclusions: If peripheral perfusion‐targeted resuscitation improves 28‐day mortality, this could lead to simpli ed algorithms, assessing almost in real‐time the reperfusion process, and pursuing more physiologically sound objec‐ tives. At the end, it might prevent the risk of over‐resuscitation and lead to a better utilization of intensive care unit resources
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