Removal of electrocardiogram distortion in portable high-power medical device

In this study, we propose a method to remove bio-signal distortions generated when the power is at transient condition in a high-powered portable medical device. To verify the method, three units were designed that consists of a main control unit, bio-signal measurement unit, and power unit. Also, each units were separated with galvanic isolation. For stable operation at the surge condition, the power unit was composed using push-pull converter topology. The design has been examined in both transient and steady state of the operating conditions. The experiment result shows that galvanic isolation between each units was efficient in high-powered potable medical device

Determining Obstruction in Endotracheal Tubes Using Physical Respiratory Signals

This study proposes a method for determining obstruction of the endotracheal tube (ET) and its degree and location. Respiratory signals were acquired using a three sensor (microphone, pressure, and flow) integrated sensor connector. Obstruction classification involved pre-processing and feature extraction. During pre-processing, one cycle of the respiratory signal was extracted using respiratory cycle extraction and phase segmentation. The signal was then divided into three phases: (i) inspiratory phase, (ii) expiratory phase, and (iii) between both the phases, where the intrapulmonary pressure increased, decreased, and remained constant, respectively. In the feature extraction process, the results were quantified using absolute value average and texture analyses. Artificial ET tubes were fabricated to simulate the presence of foreign substances in the ET tube; they had different degrees of obstruction (0%, 20%, 40%, and 50%) and obstruction positions (Sections 1, 2, and 3). The experiment was performed by connecting the sensor connector and artificial ET tube between the ventilator and test lung. Respiratory signals were obtained in 10 cases by cross connecting the artificial ET tubes. The degree and location of obstruction were classified according to the average absolute value and texture analyses of the flow data. The obstruction can be determined through the texture analysis results using the combined microphone and flow sensor data. The proposed method is simple in configuration, can be readily used in existing setups, and can be operated regardless of surrounding noise

Pseudoalteromonas byusanensis sp. nov., isolated from tidal flat sediment in Korea

A Gram-negative, motile, strictly aerobic, violet-pigment-producing bacterium, designated strain FR1199(T), was isolated from tidal flat sediment of Byunsan, South Korea. Phylogenetic analysis of the 16S rRNA gene sequence revealed that strain FR1199(T) represents a distinct line of descent within the genus Pseudoafteromonas. The phenotypic features of strain FR1199(T) were similar to those of Pseudoalteromonas phenolica and Pseudoalteromonas luteoviolacea, but several physiological and chemotaxonomical properties readily distinguished strain FR1199(T) from these species. Major fatty acids were straight-chain saturated (C-16:0) and monounsaturated C(18:1)omega 7c fatty acids. The DNA G+C content was 39 mol%. On the basis of polyphasic evidence, it is concluded that the isolate represents a novel species within the genus Pseudoalteromonas, for which the name Pseudoalteromonas byunsanensis sp. nov. is proposed. The type strain is FR1199(T) (=JCM 12483(T)=KCTC 12274(T)).

Hahella ganghwensis sp. nov., isolated from tidal flat sediment

A marine bacterial strain, designated FR1050(T), was isolated from a sediment sample of getbol (Korean tidal flat). Phylogenetic investigations based on 16S rRNA gene sequence analysis showed that the isolate formed a robust monophyletic clade with Hahella chejuensis within the gamma-Proteobacteria. Sequence similarity between strain FR1050(T) and the type strain of Hahella chejuensis was 94.7%. Cells were Gram-negative, aerobic, rod-shaped, motile and halophilic; optimum growth occurred at sea salt concentrations of 4-6%. The major fatty acids were C(18:1)w9c (39.0%) and C-16:0 (18.1%). The DNA G + C content was 44 mol%. The polyphasic data obtained showed that strain FR1050(T) is affiliated to the genus Hahella but represents a novel species for which the name Hahella ganghwensis sp. nov. is proposed. The type strain is FR1050(T) (=KCTC 12277(T)=jCM 12486(T)).

Active site structure of a lithium phosphate catalyst for the isomerization of 2,3-epoxybutane to 3-buten-2-ol

Basic lithium phosphate (B-LPO) catalyst selectively produces unsaturated alcohols from epoxides. The catalytic activity of B-LPO is known to originate from appropriate acidic-basic properties, but no details were available on the structure of the active site. In this study, experimental methods and OFT calculations were performed in an attempt to identify the active surface structure of B-LPO for the isomerization of 2,3-epoxybutane to 3-buten-2-ol. The experimental results showed that exchanged Na ions in B-LPO suppressed the formation of an acid-catalyzed by-product (methyl ethyl ketone). In addition, H2O had a negative effect on the formation of 3-buten-2-ol due to the preoccupation of the active site. OFF calculations in conjunction with these experimental observations showed that the most plausible active surface for the formation of 3-buten-2-ol is the (001) surface of LPO whose acidic proton is exchanged with Na atom. On this surface, the under-coordinated Li atoms and the surface P=O groups are exposed, and these play a role in activating the C-O bond of an epoxide ring, and in receiving a proton from the terminal carbon, respectively. (C) 2017 Elsevier B.V. All rights reserved.11Nsciescopu

Tuning the electronic state of metal/graphene catalysts for the control of catalytic activity via N- and B-doping into graphene

Catalytic activity was efficiently tuned via manipulating the electronic state of a catalyst, induced by a facile doping method in a metal/graphene system. The strategy was proven to be applicable to not only transition metal but also noble metal catalysts in CO hydrogenation and 4-nitrophenol reduction.11Nsciescopu