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1.
J Acoust Soc Am ; 148(1): 308, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32752744

RESUMO

This study quantified the microstructure of polyurethane foams and elucidated its relationship to fluid-acoustic parameters. The complex morphology derived from the three-dimensional images obtained by micro-computed tomography was analyzed using digital image processing and represented by a pore network model (PNM) and a distance map model. The PNM describes the fluid phase of a porous medium with equivalent spherical pores and circular throats, whereas the distance map model describes the solid phase with the average frame thickness. The porous materials were then modeled by six representative microstructural parameters that describe the geometry and topology of the fluid and solid phases. These parameters were pore radius, throat radius, distance between adjacent pores, coordination number, pore inclination angle, and frame thickness. Semi-phenomenological and empirical approaches were proposed to relate the microstructural properties to the fluid-acoustic parameters. These models effectively described the acoustic parameters and sound absorption performance of six different polyurethane foams. Since the representative microstructural parameters were obtained from small sample volumes of a heterogeneous material, notable variations were observed across different regions of the sample. Hence, this study quantified the effect of the uncertainty in each microstructural parameter on the resulting acoustic parameters using global sensitivity analysis.

2.
Korean J Neurotrauma ; 13(2): 141-143, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29201849

RESUMO

It is not a common case for neurosurgery department and the other departments to perform joint operation at the same time. Patients with severe head injury are a condition in which vital signs are unstable due to severe brain swelling and increased intracranial pressure, and emergency surgery is required. A 44-year-old man visited the trauma center with a motorcycle accident. The Glasgow Coma Scale score at the time of emergency department was 3 points, and the pupil was fixed at 6 mm on both sides. His medical history was unknown. His vital signs including blood pressure (BP), heart rate, respiratory rate and oxygen saturation were stable. Associated injuries included multiple fractures of whole body. Brain computed tomography revealed subarachnoid hemorrhage, intraventricular hemorrhage and severe cerebral edema. During the preparation of the craniectomy, abdominal ultrasonography performed because of decreased BP resulted in a large amount of hemoperitoneum. The bi-coronal craniectomy and splenectomy were performed simultaneously for about 4 hours. After fifty days of treatment, he was discharged with Glasgow Outcome Scale-extended 4 points and is undergoing rehabilitation. In severe polytrauma patients, active concurrent surgery is a good method to save their lives.

3.
Sci Rep ; 7(1): 12216, 2017 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-28939889

RESUMO

Pretreatment of biomass with dilute acid requires high temperatures of >160 °C to remove xylan and does not remove lignin. Here we report that the addition of peracetic acid, a strong oxidant, to mild dilute acid pretreatment reduces the temperature requirement to only 120 °C. Pretreatment of yellow poplar with peracetic acid (300 mM, 2.3 wt%) and dilute sulfuric acid (100 mM, 1.0 wt%) at 120 °C for 5 min removed 85.7% of the xylan and 90.4% of the lignin leaving a solid consisting of 75.6% glucan, 6.0% xylan and 4.7% lignin. Low enzyme loadings of 5 FPU/g glucan and 10 pNPGU/g glucan converted this solid to glucose with an 84.0% yield. This amount of glucose was 2.5 times higher than with dilute acid-pretreated solid and 13.8 times higher than with untreated yellow poplar. Thus, the addition of peracetic acid, easily generated from acetic acid and hydrogen peroxide, dramatically increases the effectiveness of dilute acid pretreatment of biomass.

4.
Neurosci Lett ; 459(1): 35-40, 2009 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-19409961

RESUMO

Attributional style means how people typically infer the causes of emotional behaviors. No study has shown neural basis of attributional style in schizophrenia, although it was suggested as a major area of social cognition research of schizophrenia. Fifteen patients with schizophrenia and 16 healthy controls underwent functional magnetic resonance imaging while performing three (happy, angry, and neutral) conditions of attribution task. Each condition included inferring situational causes of an avatar' (virtual character) emotional or neutral behavior. In the between-groups contrast maps of the happy conditions, the patient group compared to the control group showed decreased activations in the inferior frontal (BA 44) and the ventral premotor cortex (BA 6), in which the % signal changes were associated with negative symptoms. In the angry conditions, the patient group compared to the control group exhibited increased activations in the precuneus/posterior cingulate cortex (Pcu/PCC) (BA 7/31), in which the % signal changes were related to positive symptoms. In conclusion, patients with schizophrenia may have functional deficits in mirror neuron system when attributing positive behaviors, which may be related to a lack of inner simulation and empathy and negative symptoms. In contrast, patients may have increased activation in the Pcu/PCC related to self-representations while attributing negative behaviors, which may be related to failures in self- and source-monitoring and positive symptoms.


Assuntos
Encéfalo/fisiopatologia , Emoções , Expressão Facial , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Percepção Social , Mapeamento Encefálico , Lobo Frontal/fisiopatologia , Giro do Cíngulo/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Testes Neuropsicológicos , Lobo Parietal/fisiologia
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