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PURPOSE: To introduce a computational tool for peri-interventional intracranial aneurysm treatment guidance that maps preoperative planning information from simulation onto real-time X-Ray imaging. METHODS: Preoperatively, multiple flow diverter (FD) devices are simulated based on the 3D mesh of the vessel to treat, to choose the optimal size and location. In the peri-operative stage, this 3D information is aligned and mapped to the continuous 2D-X-Ray scan feed from the operating room. The current flow diverter position in the 3D model is estimated by automatically detecting the distal FD marker locations and mapping them to the treated vessel. This allows to visually assess the possible outcome of releasing the device at the current position, and compare it with the one chosen pre-operatively. RESULTS: The full pipeline was validated using retrospectively collected biplane images from four different patients (5 3D-DSA datasets in total). The distal FD marker detector obtained an average F1-score of 0.67 ( ± 0.224 ) in 412 2D-X-Ray scans. After aligning 3D-DSA + 2D-X-Ray datasets, the average difference between simulated and deployed positions was 0.832 mm ( ± 0.521 mm). Finally, we qualitatively show that the proposed approach is able to display the current location of the FD compared to their pre-operatively planned position. CONCLUSIONS: The proposed method allows to support the FD deployment procedure by merging and presenting preoperative simulation information to the interventionists, aiding them to make more accurate and less risky decisions.
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Sclerosing osteomyelitis of Garré is a rare inflammatory pathology characterized by cortical thickening and loss of the medullary canal. Typically, this pathology affects the mandible. However, the involvement of long bones, such as the femur and tibia, is also possible. This condition predominantly affects children and young adults, especially females, and commonly emerges before age 25, with an average onset age of 16 years. The disease is characterized by an insidious onset, causing local pain, distention of the affected bone, and a moderately increased erythrocyte sedimentation rate. We aim to report a unique case involving a 25-year-old Hispanic male presenting with a one-year insidious onset of left anterior lower leg pain. The patient's clinical course, laboratory findings, and imaging results are discussed. Despite a three-month trial of conservative management, symptomatic relief was elusive, prompting a left tibia core biopsy. Biopsy results revealed an inflammatory-reactive process with a xanthogranulomatous reaction. The continuation of conservative measures post-biopsy led to significant symptom resolution, highlighting the potential efficacy of histopathological examination. This case contributes to the limited literature on adult sclerosing osteomyelitis of Garré, particularly in long bones and among Hispanic individuals. Successful management through biopsy and conservative treatment provides valuable insights into therapeutic options for this rare condition.
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We summarize the application of multivariate optimization for the construction of electrochemical biosensors. The introduction provides an overview of electrochemical biosensing, which is classified into catalytic-based and affinity-based biosensors, and discusses the most recent published works in each category. We then explore the relevance of electrochemical biosensors for food safety analysis, taking into account analytes of different natures. Then, we describe the chemometrics tools used in the construction of electrochemical sensors/biosensors and provide examples from the literature. Finally, we carefully discuss the construction of electrochemical biosensors based on design of experiments, including the advantages, disadvantages, and future perspectives of using multivariate optimization in this field. The discussion section offers a comprehensive analysis of these topics.
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Técnicas Biossensoriais , Técnicas Eletroquímicas , Inocuidade dos AlimentosRESUMO
BACKGROUND: HIV infection has sustained increased in the Chilean young population. In order to focus on sexual education in adolescents, it is first necessary to establish the degree of knowledge and risk behaviors in this group. Therefore, this study aimed to compare the degree of knowledge and HIV/AIDS risk behaviors in adolescents from rural and urban schools. MATERIAL AND METHODS: The study included 385 adolescents between 14 and 18 years old. Through an anonymous survey, sociodemographic data, knowledge about HIV/ AIDS, risk behaviors, and ways of accessing information were collected. RESULTS: A third of the adolescents surveyed (33.6%) reported having initiated sexual activity, primarily men. Rural students showed lower knowledge of HIV/AIDS. 32.2% of individuals who initiated sexual activity reported nonuse or rarely use of condoms, and only 4.4% of students have had an HIV detection/diagnostic test. Although the students had received information mainly from their teachers, they reported that if they needed help, they would go to health centers, youth programs, and, to a lesser extent, to teachers. They also preferred access to information in workshops, on the Internet, and social networks. CONCLUSIONS: We observed regular knowledge of HIV/AIDS among adolescents. Rural students showed less knowledge and several risk behaviors. These findings emphasize the need to establish sexual education strategies in adolescents, considering the territory and the use of new technologies.
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Humanos , Masculino , Feminino , Adolescente , Assunção de Riscos , População Rural/estatística & dados numéricos , Comportamento Sexual/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Infecções por HIV/prevenção & controle , Infecções por HIV/epidemiologia , Conhecimentos, Atitudes e Prática em Saúde , Instituições Acadêmicas , Educação Sexual , Fatores Socioeconômicos , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Chile/epidemiologia , Estudos Transversais , Inquéritos e Questionários , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Síndrome da Imunodeficiência Adquirida/epidemiologia , Comportamento do Adolescente/psicologia , Fatores SociodemográficosRESUMO
A voltammetric electronic tongue (E-tongue) is "a multisensor system, which consists of a number of low-selective sensors and uses advanced mathematical procedures for signal processing based on pattern recognition and/or data multivariate analysis such as artificial neural networks (ANNs), principal component analysis (PCA), among others". Thus, E-tongues in combination with chemometrics tools result in more accurate and selective analytical methods. In this work, we report results of a simple and reliable electroanalytical method to determine butyl hydroxyanisole (BHA), butyl hydroxytoluene (BHT) and propyl gallate (PG) in edible olive oils (EOO). Therefore, the square wave voltammetry (SWV) was used on platinum and carbon fiber disk ultramicroelectrodes (E-tongue configuration) combined with chemometrics tools to perform these studies. On the other hand, two data fusion strategies were used in order to combine electrochemical data obtained for each working electrode in the E-tongue: low-level data fusion (LLDF) and mid-level data fusion (MLDF). In addition, to reduce the dimensionality of the dataset in MLDF, the discrete wavelet transform (DWT) was used. Finally, to assert the predictive capability of the method for BHA, BHT, and PG determination in real samples, a recovery study for the antioxidants in EOO samples was performed, demonstrating the analytical accuracy of the proposed method. Moreover, from the comparison between the proposed electrochemical method with the AOAC reference method and others found in the literature in terms of the quality of the model (REP %) and the percent recovery assays (%) in different samples, our results were better than other reported previously for the simultaneous determination of BHA, BHT, and PG in real samples. Moreover, the percent recovery assays obtained with the proposed electrochemical method were in good agreement with those obtained by the chromatographic method.
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Antioxidantes , Olea , Antioxidantes/análise , Azeite de Oliva/análise , Nariz Eletrônico , Galato de Propila/análise , Hidroxianisol Butilado/análiseRESUMO
BACKGROUND: HIV infection has sustained increased in the Chilean young population. In order to focus on sexual education in adolescents, it is first necessary to establish the degree of knowledge and risk behaviors in this group. Therefore, this study aimed to compare the degree of knowledge and HIV/AIDS risk behaviors in adolescents from rural and urban schools. MATERIAL AND METHODS: The study included 385 adolescents between 14 and 18 years old. Through an anonymous survey, sociodemographic data, knowledge about HIV/ AIDS, risk behaviors, and ways of accessing information were collected. RESULTS: A third of the adolescents surveyed (33.6%) reported having initiated sexual activity, primarily men. Rural students showed lower knowledge of HIV/AIDS. 32.2% of individuals who initiated sexual activity reported nonuse or rarely use of condoms, and only 4.4% of students have had an HIV detection/diagnostic test. Although the students had received information mainly from their teachers, they reported that if they needed help, they would go to health centers, youth programs, and, to a lesser extent, to teachers. They also preferred access to information in workshops, on the Internet, and social networks. CONCLUSIONS: We observed regular knowledge of HIV/AIDS among adolescents. Rural students showed less knowledge and several risk behaviors. These findings emphasize the need to establish sexual education strategies in adolescents, considering the territory and the use of new technologies.
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Infecções por HIV , Conhecimentos, Atitudes e Prática em Saúde , Assunção de Riscos , População Rural , Comportamento Sexual , População Urbana , Humanos , Adolescente , Masculino , Feminino , Chile/epidemiologia , População Rural/estatística & dados numéricos , Infecções por HIV/prevenção & controle , Infecções por HIV/epidemiologia , População Urbana/estatística & dados numéricos , Comportamento Sexual/estatística & dados numéricos , Inquéritos e Questionários , Comportamento do Adolescente/psicologia , Estudos Transversais , Fatores Socioeconômicos , Estudantes/estatística & dados numéricos , Estudantes/psicologia , Instituições Acadêmicas , Fatores Sociodemográficos , Educação Sexual , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Síndrome da Imunodeficiência Adquirida/epidemiologiaRESUMO
Recent studies prove a strong association between reading and eye movements. Few investigations report the role of connectors and prior knowledge during reading in Spanish, as well as their association with eye movements. The present study aims to evaluate the effects of the presence absence of connectors in two argumentative texts on cognitive effort and reading comprehension. Forty-one psychology undergraduate students participated in a reading comprehension task, while their eye movements were recorded. The condition with connectors was related to prior knowledge, the slide time fixation, the slide number fixations, and the slide return fixations. The condition without connectors was related to the return fixations, the time fixation, and the number of fixations. Prior knowledge was correlated with the total time fixation, the total return fixations, and comprehension. This suggests that during reading without connectors more cognitive effort is required, observed in the return fixations; moreover, prior knowledge has an important role in the visual strategies required to process and obtain a representation of text. But participant performance was still good as observed in the scores of the reading comprehension task
Estudios prueban una asociación entre lectura y movimientos oculares al reportar el efecto de los conectores en el procesamiento textual. Pocas investigaciones revelan el papel de los conectores, el conocimiento previo y los movimientos oculares en la lectura de textos en español. El objetivo fue evaluar los efectos de la presencia-ausencia de conectores en dos textos argumentativos sobre el esfuerzo cognitivo y la comprensión lectora. Participaron 41 universitarios en una tarea de lectura con registro de sus movimientos oculares. La comprensión en la condición con conectores estuvo relacionada con conocimiento previo, tiempo y número de fijaciones por diapositiva, además del número de regresos en la lectura por diapositiva. Mientras la comprensión de textos sin conectores estuvo relacionada con conocimiento previo, regresos, tiempo y número de fijaciones, el conocimiento previo se correlacionó con tiempo y número fijaciones, regresos en la lectura y la comprensión. Se sugiere que la lectura de un texto sin conectores requerirá mayor esfuerzo cognitivo observado en los regresos en la lectura; además, el conocimiento previo afecta las estrategias visuales para procesar y representar mentalmente un texto. Pero, el desempeño de los participantes sigue siendo bueno, según lo observado en los puntajes de la tarea de comprensión lectora.
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Humanos , Leitura , Compreensão , Movimentos Oculares , Conectoma/psicologiaRESUMO
Intra-saccular devices (ID) are novel braided devices used for complex intracranial aneurysms treatment. Treatment success is associated with correct device size selection. A technique that predicts the ID size within the aneurysm before intervention will provide a powerful computational tool to aid the interventionist during device selection. We present a method to calculate the device's final height, radial expansion and porosity within the patient's anatomy, which allows assessing different device sizes before treatment takes place. The proposed sizing technique was tested in-vitro and in real patient's geometries obtained from 3DRA angiographic images of 8 unruptured aneurysms previously treated with IDs. The obtained simulated height was compared to the real height, with a mean error of less than 0.28 mm (±0.44). The porosity calculation method was tested in-vitro with an error of 0.02 (±0.022). The results of both sizing and porosity experiments resemble well measures from real patients. This methodology could be used before treatment to provide the interventionist with additional information that allows selecting the device that best fits the patient's aneurysm to be treated.
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Embolização Terapêutica , Aneurisma Intracraniano , Simulação por Computador , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Porosidade , StentsRESUMO
PURPOSE: Hurricane Maria is the most devastating natural phenomenon in the recent history of Puerto Rico. Due to its destructive path through the island, the Puerto Rico Trauma Center (PRTC) remained the only hospital managing orthopaedic trauma in the immediate post-disaster period. We investigated the impact of this hurricane on the orthopaedic trauma epidemiology in the PRTC. METHODS: We evaluated the admissions by the orthopaedic surgery service in terms of demographics, mechanisms of injury, and orthopaedic diagnoses for two months after the impact of Hurricane Maria (HM) on September 20, 2017. We compared our study group with the same two month period for two years prior (2015 and 2016) and after (2018 and 2019) as control periods. A p value of < 0.05 was considered statistically significant. RESULTS: We included 384 admissions from September 20 to November 20, 2017. The majority were males (63%) and had an average age of 54 years. The most-reported mechanism of injury was fall from standing height (FFSH), showing a significant increment compared with the control periods. Contrarily, motor vehicle accidents (MVA) showed a significant reduction. Among the orthopaedic diagnoses, the hip + pelvis category showed a significant decline within the study group. CONCLUSIONS: This study highlighted the impact of HM on the orthopaedic trauma epidemiology at the PRTC. Our findings provide valuable evidence to healthcare institutions to better prepare to manage the potential changes in the orthopaedic trauma epidemiology after a major atmospheric event.
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Tempestades Ciclônicas , Ortopedia , Feminino , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Porto Rico/epidemiologia , Centros de TraumatologiaRESUMO
INTRODUCTION AND IMPORTANCE: Actinomycosis is a chronic granulomatous disease associated with the Actinomyces species. This unusual condition, especially in the musculoskeletal system, has been considered a diagnostic challenge due to its initial non-specific symptoms requiring high clinical suspicion and an adequate diagnostic approach for its identification. CASE PRESENTATION: We present the case of a 39-year-old Hispanic female with right knee pain and associated purulent secretions for the past four years, who demonstrated persistent synovial actinomycosis despite arthrotomy with cleansing and debridement plus a long-term antibiotic regime. CLINICAL DISCUSSION: Actinomyces species remain a rare cause of musculoskeletal disease. Its presentation could include localized swelling, tissue fibrosis, sinus tracts, or an abscess, yet these symptoms are not specific, requiring high clinical suspicion to avoid a potential misdiagnosis. Culture in an anaerobic media and pathologic specimens are vital diagnostic tools. Among the treatment alternatives, antimicrobial therapy and surgery are usually required to manage bone and joint infections. Adequate antibiotic selection is crucial, as suboptimal treatment could promote the development of a persistent infection. CONCLUSION: This case highlights the diagnostic challenge of synovial actinomycosis, a rarely reported condition in native knee joints. High clinical suspicion is critical as early diagnosis, and adequate management is essential to avoid a persistent infectious process.
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A novel analytical method using voltammetric second-order modeling based on multivariate curve resolution-alternating least-square (MCR-ALS) is presented for the first time for the quantitation of carvacrol (CAR) in oregano essential oils (OEO). The second-order cyclic voltammetry data were generated on the basis that CAR shows a diffusional system. Thus, the scan rate (v) was used as a second instrumental mode and cyclic voltammograms at different v were acquired for a single sample, generating the second-order data. CAR determination was performed in presence of thymol, included as a potential interferent. Results demonstrated that MCR-ALS successfully exploited the second-order advantage and the recoveries were not statistically different than 100%. The limits of detection and quantitation were estimated using the MCR-ALS which were 6.27 × 10-5°mol°L-1°and 1.90 × 10-4°mol L-1, respectively. Finally, the developed methodology was implemented to quantify of CAR in OEO samples.
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Óleos Voláteis , Origanum , Cimenos , TimolRESUMO
MOTIVATION: Intra-saccular devices (ID), developed for the treatment of bifurcation aneurysms, offer new alternatives for treating complex terminal and bifurcation aneurysms. In this work, a complete workflow going from medical images to post-treatment CFD analysis is described and used in the assessment of a concrete clinical problem. MATERIALS AND METHODS: Two different intra-saccular device sizes were virtually implanted in 3D models of the patient vasculature using the ID-Fit method. After deployment, the local porosity at the closed end of the device in contact with the blood flow was computed. This porosity was then used to produce a CFD porous medium model of the device. Velocities and wall shear stress were assessed for each model. RESULTS: Six patients treated with intra-saccular devices were included in this work. For each case, 2 different device sizes were virtually implanted and 3 CFD simulations were performed: after deployment simulation with each size and before deployment simulation (untreated). A visible reduction in velocities was observed after device implantation. Velocity and WSS reduction was statistically significant (K-S statistics, [Formula: see text]). CONCLUSIONS: Placement of different device size can lead to a partial filling of the aneurysm, either at the dome or at the neck, depending on the particular positioning by the interventionist. The methodology used in this work can have a strong clinical impact, since it provides additional information in the process of device selection using preoperative data.
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Aneurisma Intracraniano , Simulação por Computador , Hemodinâmica , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Modelos Cardiovasculares , Estresse MecânicoRESUMO
Introducción: En 1967 se estableció, por primera vez, un comité de monitoreo de datos, en un estudio de mortalidad cardiovascular; desde entonces su uso se ha incrementado debido a su valor para garantizar la seguridad de los sujetos participantes en ensayos clínicos y la validez e integridad de los datos. Se realizó una exploración documental de los últimos 20 años, sobre aspectos relacionados con los requisitos de creación y funcionamiento de los comités de monitoreo de datos a nivel mundial, con los objetivos de mostrar el desarrollo alcanzado en el establecimiento de los comités de monitoreo de datos e identificar sus características fundamentales. Desarrollo: Existe un incremento en la producción documental sobre los comités de monitoreo de datos, liderado por angloparlantes de países desarrollados, con franco aumento de publicaciones sobre el tema en el último quinquenio, superior en 50 por ciento a los 15 años anteriores. Este fenómeno lo provoca el auge de la industria farmacéutica y biotecnológica, los altos costos de investigación y desarrollo de medicamentos, la necesidad de introducir nuevos fármacos y el incremento de las exigencias regulatorias. Se describen las características estructurales, requisitos clínicos y metodológicos para el establecimiento de los comités. Conclusiones: Existe alto desarrollo de los comités de monitoreo de datos en los ensayos clínicos, con tendencia al incremento de su uso en los últimos años. Los comités de monitoreo de datos se caracterizan por requerimientos clínicos y metodológicos para su establecimiento(AU)
Introduction: For the first time, in 1967, a data monitoring committee was established in a study of cardiovascular mortality. Since then its use has increased, due to its value to guarantee the safety of subjects participating in clinical trials, the validity and integrity of the data. A documentary exploration of the last 20 years was carried out, on aspects related to the requirements for the creation and operation of data monitoring committees worldwide, with the aim of showing the development achieved in the establishment of data monitoring committees and identify its fundamental characteristics. Development: There is an increase in documentary production on data monitoring committees, led by English speakers from developed countries, with a clear increase in publications on the subject, in the last five-year period, 50% higher than in the previous 15 years. This phenomenon is caused by the rise of the pharmaceutical and biotechnology industry, the high costs of drug research and development, the need to introduce new drugs and the increase in regulatory requirements. The structural characteristics, clinical and methodological requirements for the establishment of the committees are described. Conclusions: There is a high development of data monitoring committees in clinical trials, with a tendency to increase their use in recent years. Data monitoring committees are characterized by clinical and methodological requirements for their establishment(AU)
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Humanos , Monitoramento Ambiental , Comitês de Monitoramento de Dados de Ensaios Clínicos , Indústria Farmacêutica , Medicamentos de Referência , Preparações Farmacêuticas , Custos e Análise de CustoRESUMO
Background: Flow-Diverter (FD) porosity has been pointed as a critical factor in the occlusion of cerebral aneurysms after treatment. Objective: Verification and Validation of computational models in terms of predictive capacity, relating FD porosity and occlusion after cerebral aneurysms treatment. Methods: Sixty-four aneurysms, with pre-treatment and follow-up images, were considered. Patient demographics and aneurysm morphological information were collected. The computational simulation provided by ANKYRAS provided FD porosity, expansion, and mesh angle. FD occlusion was assessed and recorded from follow-up images. Multiple regression Logit and analysis of covariance (ANCOVA) models were used to model the data with both categorical and continuous models. Results: Occlusion of the aneurysm after 12 months was affected by aneurysm morphology but not by FD mesh morphology. A Time-To-Occlusion (TTO) of 6.92 months on average was observed with an SE of 0.24 months in the aneurysm population surveyed. TTO was estimated with statistical significance from the resulting model for the data examined and was capable of explaining 92% of the data variation. Conclusions: Porosity was found to have the most correction power when assessing TTO, proving its importance in the process of aneurysm occlusion. Still, further Verification and Validation (V&V) of treatment simulation in more extensive, multi-center, and randomized databases is required.
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BACKGROUND: Controlled donation after circulatory death (cDCD) has emerged as one of the main strategies for increasing the organ donor pool. Because of the ischemic injury that follows the withdrawal of life-sustaining therapies, hearts from cDCD donors have not been considered for transplantation until recently. The ex-situ perfusion of hearts directly procured from cDCD donors has been used to allow the continuous perfusion of the organ and the assessment of myocardial viability prior to transplantation. Based on our experience with abdominal normothermic regional perfusion in cDCD, we designed a protocol to recover and validate hearts from cDCD donors using thoraco-abdominal normothermic regional perfusion without the utilization of an ex-situ device. CASE PRESENTATION: We describe the first case of a cDCD heart transplant performed with this approach in Spain. The donor was a 43-year-old asthmatic female diagnosed with severe hypoxic encephalopathy. She was considered a potential cDCD donor and a suitable candidate for multiorgan procurement including the heart via thoraco-abdominal normothermic regional perfusion. The heart recipient was a 60-year-old male diagnosed with amyloid cardiomyopathy. Cold ischemia time was 55 min. The surgery was uneventful. CONCLUSIONS: This case report, the first of its kind in Spain, supports the feasibility of evaluating and successfully transplanting cDCD hearts without the need for ex-situ perfusion based on the use of thoraco-abdominal normothermic regional perfusion opening the way for multiorgan donation in cDCD.
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Oxigenação por Membrana Extracorpórea , Transplante de Coração , Perfusão/métodos , Coleta de Tecidos e Órgãos/métodos , Abdome , Adulto , Morte , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espanha , Tórax , Doadores de TecidosRESUMO
Normothermic regional perfusion (NRP) in controlled donation after circulatory death is becoming a popular method due to the favorable results of the grafts procured under this technique. This procedure requires experience, and, sometimes, the availability of extracorporeal membrane oxygenation (ECMO) machines to implement NRP is limited to tertiary hospitals. In order to provide support with NRP in controlled donation after circulatory death across the different hospitals of the Autonomous Community of Madrid, a mobile NRP team was created. In the first 18 months since its creation, the mobile NRP team participated in 33 procurements across nine different hospitals, representing 72% of all controlled donations after circulatory death in the Autonomous Community of Madrid. NRP was successfully performed in 29 (88%) cases, with a mean duration of 69 ± 27 minutes. A total of 39 kidneys, 12 livers, and 5 bilateral lungs were recovered and transplanted. None of the livers were discarded due to an elevation in transaminases during NRP. A mobile NRP team is a feasible option and, in our series, aided in the optimization and recovery of organs from donors after controlled circulatory death in centers where ECMO technology was not available.
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Oxigenação por Membrana Extracorpórea , Obtenção de Tecidos e Órgãos , Morte , Humanos , Preservação de Órgãos , Perfusão , Projetos Piloto , Doadores de TecidosRESUMO
A GCE/CRGO-ßCD's/ADA-SPE/AuNPs biosensor was successfully developed to determine eugenol in dental samples. The optimal conditions to construct the biosensor were obtained from an experimental design based on the response surfaces methodology. The GCE/CRGO-ßCD/ADA-SPE/AuNPs biosensor exhibited a very good analytical performance for the quantification of eugenol. Thus, it shows a linear range between 1.3 × 10-8 and 1 × 10-5 mol L-1, with a sensitivity of (5.3 ± 0.3) x 10-3 A mol-1 L. The limits of detection and quantification were 4 × 10-9 mol L-1 and 1.3 × 10-8 mol L-1, respectively. Biosensors had an intraday and inter day reproducibility of 5% and 8%, respectively. The repeatability was of 3%, and the stability was 21 days (a decrease of 30% in current responses was observed after the fourth week). Recovery studies were performed in order to validate the proposed method. Recovery percentages were between 94 and 108%. A value of the apparent Michaellis-Menten constant, KMapp, of 3.1 × 10-6 mol L-1 was obtained using both Lineweaver-Burk and Eadi-Hofstee methods.
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Resinas Acrílicas/química , Técnicas Biossensoriais , Técnicas Eletroquímicas , Eugenol/análise , Restauração Dentária Permanente , Eletrodos , Eugenol/metabolismo , Humanos , Estrutura Molecular , Extração DentáriaRESUMO
Although entrepreneurial intention has been widely studied using cognitive models, we still lack entrepreneurial vocation and, therefore, lack disruptive innovations. Entrepreneurship scholars have some understanding of the reasons underlying this weakness, although there is much room for improvement in our learning concerning how to promote entrepreneurship among university students, especially in the transformed context of digital technologies. This paper focuses on the early stages of start-up, and in particular seeks to evaluate what role social and psychological factors play in the development of entrepreneurial intentions. Drawing on network theory, we consider the impact of social networks on entrepreneurial intention. Specifically, we analyze the influence of two types of social networks: face-to-face and online social networks, with the latter proving especially important in digital transformations. In addition, based on affective congruency theory, we relate affect with entrepreneurial intention. Particularly, we evaluate the influence of positive and negative dispositional affectivity on the formation of entrepreneurial intentions. Finally, since affect and emotions can also be related with social relationships, we analyze whether dispositional affectivities influence entrepreneurial intention through the mediation effect of social networks. Using structural equation modeling, we confirm the impact of both online and face-to-face social networks, as well as positive dispositional affectivity on entrepreneurial intention for 589 higher education students in Spain. However, negative dispositional affectivity is not seen to influence entrepreneurial intention. Furthermore, both face-to-face and online social networks are influenced by positive dispositional affectivity. Moreover, these two types of networks can even partially mediate the relationship between positive dispositional affectivity and entrepreneurial intention. Positive dispositional affectivity can thus influence entrepreneurial intention in two different ways: directly and indirectly through both face-to-face and online social networks. This study provides further insights and adds to the literature on affect, social networks, and entrepreneurial intention. From a broader perspective, we also contribute to the literature on disruptive innovations by explaining how the development of entrepreneurial intentions would have positive consequences for university students vis-à-vis achieving these disruptive innovations.