Sincronização de sistemas lur’e com controle amostrado

Este trabalho apresenta soluções para o problema de sincronização de sistemas Lur’e mestre-escravo através de uma lei de controle. Inicialmente, o caso de sistemas em tempo discreto é formulado com um controle saturante. Em seguida, no caso de sistemas em tempo contínuo, considera-se um controle a partir de dados amostrados (sampled-data control). A sincronização é abordada como um problema de estabilização do erro entre os estados dos sistemas mestre e escravo, e o controle projetado através de um problema de otimização. No caso de sistemas em tempo discreto, a partir de uma função de Lyapunov quadrática e condições de setor, desigualdades matriciais lineares (LMI) são obtidas com o objetivo de garantir que a diferença entre os estados mestre e escravo convirja assintoticamente para zero na ocorrência da saturação do sinal de controle. Condições de estabilidade seguindo uma modelagem por funções zona-morta também são obtidas, no caso particular onde a não linearidade Lur’e é descrita por uma função linear por partes. Um problema de otimização para o projeto do controlador é proposto com o objetivo de maximizar um conjunto de erros iniciais admissíveis, para os quais a sincronização é garantida. Na abordagem via controle amostrado são considerados uma função de Lyapunov do tipo Lur’e e um funcional looped para a obtenção de condições LMI que garantam a sincronização de sistemas mestre-escravo sempre que o intervalo entre duas amostras respeitar um determinado limite. Um problema de otimização que visa maximizar o intervalo admissível entre duas amostras consecutivas é apresentado. Os resultados das metodologias propostas são avaliados através de exemplos numéricos.This work presents solutions to the synchronization problem of master-slave Lur’e systems via a control law. Initially, the discrete-time systems case is formulated under a saturating control. Then, in the continuous-time systems case, a sampled-data control is considered. Synchronization is addressed as a problem of stabilization of the error between the states of the master and slave systems and the control is designed via an optimization problem. In the discrete-time systems case, from a quadratic Lyapunov function and sector conditions, linear matrix inequalities (LMI) are derived with the objective of ensuring that the difference between the master and slave states converges asymptotically to zero under the saturation of the control signal. Stability conditions based on a dead zone function modeling are also obtained, in the particular case where the Lur’e nonlinearity is described by a piecewise-linear function. An optimization problem for the controller design is proposed in order to maximize a set of admissible initial errors for which the synchronization is guaranteed. In the sampled-data control approach, a Lur’e-type Lyapunov function and a loopedfunctional are considered to derive LMI conditions that guarantee the synchronization of master-slave systems whenever the interval between two samples respects some bounds. An optimization problem that aims to maximize the allowable interval between two consecutive samples is presented. The results of the proposed methodologies are evaluated with numerical examples

Disclosure de operações de derivativos: evolução e grau de cumprimento da instrução CVM n° 235/95 e deliberação CVM n° 550/08

The objective of this study is to analyze the evolution and the compliance degree with the disclosure of information of transactions with derivative instruments of companies Aracruz Celulose, Suzano Papel e Celulose, Votorantim Papel e Celulose (VCP), Sadia and Perdigão, in line with the CVM Instruction n° 235/95 and CVM Resolution n. 550/08, in the period of 2004 to the first quarter of 2009. It was noted that the companies did not meet all the requirements of CVM information n° 235. The compliance of the instruction was partial in all companies. The level of disclosure was less related to aspects of policy and performance, control and was nonexistent in all cases regarding the disclosure of the risks involved. The companies did not show evolution of compliance of the statement. And there were no significant differences between the disclosure degree about derivative transactions between the group of which it suffered substantial losses (Sadia, Aracruz and VCP) and other enterprises (Perdigão and Suzano P.C.) The compliance of the aspects of disclosure required by CVM n. 550, noted an immediate growth of the level of disclosure and an evolution between the third quarter of 2008 and first quarter of 2009, what the companies eventually demonstrate fully the requirements of the deliberation. The results found support arguments that there is not sufficient evidence to suggest that the legislation will improve the quality of accounting information. The same, nor is there sufficient evidence to assert that market discipline is sufficient to ensure the appropriate level of disclosure. Therefore, there may be a complementarity between these two elements.Key words: disclosure, derivatives, CVM instruction n. 235/95, CVM deliberation n. 550/08.O objetivo do presente estudo é analisar a evolução e o grau de cumprimento do disclosure de informações de operações com instrumentos derivativos das companhias Aracruz Celulose, Suzano Papel e Celulose, Votorantim Papel e Celulose, Sadia e Perdigão, em consonância com a instrução CVM n° 235/95 e resolução CVM n° 550/08, no período de 2004 ao primeiro trimestre de 2009. Observou-se que as empresas não atenderam a totalidade das exigências do Informativo CVM n° 235. O cumprimento da instrução foi parcial em todas as companhias. O nível de disclosure foi menor quanto aos aspectos relacionados à política de atuação e controle, e foi inexistente em todos os casos quanto à divulgação dos riscos associados. As companhias não apresentaram evolução do grau de cumprimento da instrução. E não foram encontradas diferenças significativas entre o grau de disclosure sobre as operações de derivativos entre o grupo de que sofreram perdas vultosas (Aracruz, Sadia e VCP) e demais empresas (Perdigão e Suzano P.C.). Quanto ao cumprimento dos aspectos de evidenciação exigidos pela deliberação CVM no 550, observou-se um imediato crescimento do nível de disclosure e uma evolução entre o terceiro trimestre de 2008 e o primeiro de trimestre de 2009, período em que as companhias acabaram por evidenciar plenamente as exigências da deliberação. Os resultados encontrados dão suporte aos argumentos de que não há evidências suficientes para sugerir que a regulamentação melhore a qualidade da informação contábil. Do mesmo, também não há evidencias suficientes para afirmar que a disciplina de mercado seja suficiente para garantir o nível de disclosure adequado. Portanto, pode existir uma complementaridade entre estes dois elementos.Palavras-chave: evidenciação, derivativos, instrução CVM n° 235/05, deliberação CVM n° 550/08

Intervertebral Disc Extrusion between T8 and T9 in a Dachshund

Background: Intervertebral disc extrusion with consequent spinal compression or intervertebral disc disease (IVDD) is one of the most common causes of compressive myelopathy in dogs, and the thoracolumbar spine discs between T12 and L2 are most affected. Extrusions in cranial thoracic region are rare, and there is few cases in literature reporting this situations, this rarity is attributed to the presence of the intercapital ligament connecting the rib heads between T2 and T10, which strengthens this region both mechanically and anatomically. The aim of this article is report the clinical signs, diagnosis and treatment of a case of Type I Hansen IVDD between T8 and T9 in a Dachshund breed dog.Case: An 8-year-old Dachshund male dog was presented for investigation of pelvic limb incoordination and back pain, which started 10 days prior to the consultation. It had a history of a similar condition 3 months earlier that showed improvement after clinical treatment. On neurological examination was identified in both pelvic limbs proprioceptive ataxia, absence of proprioception, increased muscle tone, presence of interdigital reflex and increased patellar reflex. Cutaneous trunci reflex was absent below T11 on the left side, and pain was noted upon palpation of T7 through the T12 vertebrae. A grade II asymmetric thoracolumbar lesion with hyperesthesia was diagnosed. On suspicion of IVDD, cerebrospinal fluid (CSF) collection and CT scan analysis of the thoracolumbar region were performed. CT scan showed the presence of hyperattenuating and mineralized material, 1 cm long, on the floor of the spinal canal, mainly on the left side, occupying 80% of the diameter of the spinal canal between T8 and T9. The patient was then submitted to decompression surgery through hemilaminectomy and showed a good recovery. As the occurrence of disc extrusion in cranial thoracic region of chondrodystrophic breeds is rare, we report the clinical signs, diagnosis and treatment of a case of Type I Hansen intervertebral disc disease (IVDD) between T8 and T9 in a Dachshund breed dog.Discussion: All spinal discs can undergo a process of degeneration causing IVDD, in which the cervical and thoracolumbar regions are the most affected due to reasons not yet fully understood, however spinal cord compression between the T1 and T9 vertebrae is very rare, probably due to the strengthening provided by the intercapital ligament to the posterior annulus fibrosus. Disc extrusion in unusual locations in chondrodystrophic breeds is mainly reported as extrusion between vertebrae T1 and T2, and T9 and T10, with some cases was attributed to an anatomical abnormality of the intercapital ligament. The evaluation of intervertebral discs of the German shepherd breed dogs using MRI showed disc degeneration processes in thoracic vertebras. Disc extrusions often result in more severe clinical signs than protrusions, and occur acutely or subacutely, which was different from the case described here, maybe because the presence of the intercapital ligament permitted gradual extrusion allowing the spinal cord to adapt to the compression. Despite surgical access to this region being described as more complex due to the presence and proximity of the rib head to the vertebral body and the possibility of injuring the intercostal muscles causing pneumothorax, the hemilaminectomy and rib head excision at T9 could be performed without any complications. Thus, although unusual, the cranial thoracic region should not be overlooked as a possible site of occurrence of IVDD, since the diagnosis, treatment and prognosis are similar to those in patients with extrusions in the most common sites.Keywords: intervertebral disc degeneration, dogs, paresis, ataxia

Weekend-Based Parent-Group Intervention to Reduce Stress in Parents of Children and Adolescents with Type 1 Diabetes: A Pilot Study

Diagnosis of type 1 diabetes (T1D) in a child is often associated with anger, denial, fear, and depression from the parents. The aim of the study was to improve parents' adaptation to the diagnosis of diabetes of their child. Sixty-two parents (29 mothers, 33 fathers) of 36 children with type 1 diabetes (mean age=11.3-3.3 years; diabetes duration>1 year; HbA1c=57 +/- 11 mmol/mol) participated in a three-day educational working group pilot intervention study. Intervention was based on the reexamination of the traumatic event of diagnosis of T1D through spatial and time-line anchorage, retracing of the future, emotional awareness, and interactive discussion. Relaxing technique, diaphragmatic breathing, and guided visualization were used by 2 psychologists and 1 pediatric endocrinologist. The study was approved by EC and participants filled a consent form. At baseline and after intervention, parents filled in a questionnaire including Diabetes-Related Distress (DRD), Parent Health Locus of Control Scale (PHLOC), Parent Stress Index Short Form (PSI-SF), Hypoglycemia Fear Survey-Parents (HFS-P) and Hypoglycemia Fear Survey-Parents of Young Children (HFS-P-YC), and Health Survey Short Form-36 (SF-36). Three months after the intervention, both parents reported a reduction in the "difficult child" subscale of the PSI-SF (p<0.05) and increased scores of social functioning of the SF-36 (p<0.05). DRD score was significantly reduced in mothers (p=0.03), while the "parental distress" subscale of the PSI-SF was significantly improved in fathers (p=0.03). This weekend-based parent group intervention seems to reduce stress and improve social functioning of parents of children and adolescents with type 1 diabetes

Lung Ultrasound in COVID-19 Pneumonia: Correlations with Chest CT on Hospital admission

Background: Lung ultrasound (LUS) is an accurate, safe, and cheap tool assisting in the diagnosis of several acute respiratory diseases. The diagnostic value of LUS in the workup of coronavirus disease-19 (COVID-19) in the hospital setting is still uncertain. Objectives: The aim of this observational study was to explore correlations of the LUS appearance of COVID-19-related pneumonia with CT findings. Methods: Twenty-six patients (14 males, age 64 ± 16 years) urgently hospitalized for COVID-19 pneumonia, who underwent chest CT and bedside LUS on the day of admission, were enrolled in this observational study. CT images were reviewed by expert chest radiologists, who calculated a visual CT score based on extension and distribution of ground-glass opacities and consolidations. LUS was performed by clinicians with certified competency in thoracic ultrasonography, blind to CT findings, following a systematic approach recommended by ultrasound guidelines. LUS score was calculated according to presence, distribution, and severity of abnormalities. Results: All participants had CT findings suggestive of bilateral COVID-19 pneumonia, with an average visual scoring of 43 ± 24%. LUS identified 4 different possible -abnormalities, with bilateral distribution (average LUS score 15 ± 5): focal areas of nonconfluent B lines, diffuse confluent B lines, small subpleural microconsolidations with pleural line irregularities, and large parenchymal consolidations with air bronchograms. LUS score was significantly correlated with CT visual scoring (r = 0.65, p < 0.001) and oxygen saturation in room air (r = -0.66, p < 0.001). Conclusion: When integrated with clinical data, LUS could represent a valid diagnostic aid in patients with suspect COVID-19 pneumonia, which reflects CT findings

The Early Growth Response Gene EGR-1 Behaves as a Suppressor Gene That Is Down-Regulated Independent of ARF/Mdm2 but not p53 Alterations in Fresh Human Gliomas.

EGR-1 is an immediate early gene with diverse functions that include the suppression of growth. EGR-1 is down-regulated many cancer cell types, suggesting a tumor suppressor role, and may critically involve the p53 pathway. The aim of this work was to measure the expression of EGR-1 and the p16/INK4a/ARF-Mdm2-p53 pathway status in fresh human gliomas. Thirty-one human gliomas with different grades of malignancy were investigated for Egr-1 mRNA and the protein expression, frequency, and spectrum of p53 gene mutations, mdm2 gene amplification, and p16/INK4a/ARF allele loss. The amplification of Mdm2 and the deletion of the p16/INK4a gene was found in 3 and 5 cases, respectively, whereas mutations of p53, including two novel mutations, were observed in 10 other cases. The three types of changes occurred strictly mutually exclusively, emphasizing that these genes operate in a common pathway critical to glioma progression. EGR-1 mRNA was significantly down-regulated in astrocytomas (14.7 +/- 5.1%) and in glioblastomas (33.6 +/- 10.0%) versus normal brain. Overall, EGR-1 mRNA was strongly suppressed (average, 15.2 +/- 13.9%) in 27 of 31 cases (87%), independent of changes in p16/INK4a/ARF and Mdm2; whereas 4 of 31 cases with residual EGR-1 expression as well as the highest EGR-1 variance segregated with p53 mutations. Immunohistochemical analyses confirmed the suppression of EGR-1 protein. These results indicate that EGR-1 is commonly suppressed in gliomas independent of p16/INK4a/ARF and Mdm2 and that suppression is less crucial in tumors bearing p53 mutations, and these results implicate an EGR-1 growth regulatory mechanism as a target of inactivation during tumor progression

Los cursos online masivos abiertos – MOOC como estrategia de marketing en las universidades

El marketing aplicado a las tecnologías modifica las prácticas y vías tradicionales en las que se ejecuta la información y la comunicación. Bajo la noción acerca de la composición básica del marketing tradicional que es definida por producto, precio, plaza y promoción. La estrategia de marketing con enfoque en las tecnologías transforma las reglas y amplían la noción incorporando asociaciones y la protección a los derechos autorales. La promoción de un producto tecnológico educativo gratuito mediante diversos recursos (redes sociales) conduce al usuario al acceso y aprendizaje de diferentes servicios. Hablando de Marketing, en el campo de la educación, es importante que las variables del producto/servicio tecnológico estén disponibles y con fácil acceso. Estudio señalan que la esencia del marketing comienza en la idealización del concepto, basándose en las necesidades presentadas por el objeto en estudio, concepto realizado a partir de una planeación para establecer acciones y propuestas. La vertiente de esta investigación tiene el enfoque en la tecnología de la información en marketing, un recurso de la filosofía de la gestión administrativa, y es entendido como una de las tareas del marketing dirigido a la información, buscando suministrar resultados positivos a las organizaciones. El objetivo de la investigación es la aplicación de esa vertiente a la Educación por medio de la divulgación de un Curso Online Masivo Abierto o MOOC por sus siglas en inglés (Masive Open Online Courses) partiendo del recuso de un video paper disponible en el Repositorio de Contenido de Información en Filmes (RECIF), dónde se conceptualiza este video como un Recurso Educativo Abierto (REA). De esta forma el curso es ofrecido sin costos, de forma libre y el aprendizaje es autónomo, permitiendo aún su reutilización por diferentes vías de administración educativa. El video paper del curso fue idealizado en el Encuentro Latinoamericano de Edificaciones y Construcciones Sustentables – ELECS en sus versiones 2013 y 2015m. En esta investigación la reutilización de video papers bajo la forma de un curso se define en el transcurso de la misma como una estrategia de marketing de la información que favorece la diseminación del tema sustentabilidad ambiental. Las redes sociales involucradas fueron Facebook®, Twitter®, entre otras. Por lo que se procedió a realizarse una planeación de una campaña de marketing seguida de la inserción en la internet conforme a la formulación de un plan de marketing basado en la literatura estudiada. El monitoreo de las acciones y sus resultados fueron medidos en la búsqueda de indicadores a partir del número de visualizaciones de los videos antes y después de la campaña de marketing. En resumen, en la investigación una vez que se usa el concepto REA al video paper, se aplica una vertiente del marketing – de la información – a fin de diseminar el curso en redes sociales y adecuarlo a las exigencias de un MOOC

Effect of mild hypercapnia on outcome and histological injury in a porcine post cardiac arrest model

Aim of the study: To evaluate in an established porcine post cardiac arrest model the effect of a mild hypercapnic ventilatory strategy on outcome. Methods: The left anterior descending coronary artery was occluded in 14 pigs and ventricular fibrillation induced and left untreated for 12 min. Cardiopulmonary resuscitation was performed for 5 min prior to defibrillation. After resuscitation, pigs were assigned to either normocapnic (end-tidal carbon dioxide (EtCO2) target: 35-40 mmHg) or hypercapnic ventilation (EtCO2 45-50 mmHg). Hemodynamics was invasively measured and EtCO2 was monitored with an infrared capnometer. Blood gas analysis, serum neuron-specific enolase (NSE) and high sensitive cardiac troponin T (hs-cTnT) were assessed. Survival and functional recovery were evaluated up to 96 h. Results: Twelve pigs were successfully resuscitated and eight survived up to 96 h, with animals in the hypercapnic group showing trend towards a longer survival. EtCO2 and arterial partial pressure of CO2 were higher in the hypercapnic group compared to the normocapnic one (p <0.01), during the 4-hour intervention. Hypercapnia was associated with higher mean arterial pressure compared to normocapnia (p <0.05). No significant differences were observed in hs-cTnT and in NSE between groups, although the values tended to be lower in the hypercapnic one. Neuronal degeneration was lesser in the frontal cortex of hypercapnic animals compared to the normocapnic ones (p <0.05). Neurological recovery was equivalent in the two groups. Conclusion: Mild hypercapnia after resuscitation was associated with better arterial pressure and lesser neuronal degeneration in this model. Nevertheless, no corresponding improvements in neurological recovery were observed.Peer reviewe