5,376 research outputs found
Enhanced Intracellular Uptake of CdTe Quantum Dots by Conjugation of Oligopeptides
Arg-Gly-Asp-Ser (RGDS), a typical membrane-permeable carrier peptide, was conjugated with mercaptoisobutyric acid-immobilized CdTe quantum dot (CTNPs) to enhance the intracellular uptake of quantum dots. Mean size of mercaptoisobutyric acidimmobilized quantum dots (37 nm) as determined by dynamic light scattering was increased up to 54 nm after RGDS immobilization.
It was found, from in vitro cell culture experiment, that fibroblast (NIH 3T3) cells were well proliferated in the presence of RGDS-conjugated quantum dots (RCTNPs), and the intracellular uptake of CTNPs and RCTNPs was studied by means of ICP and fluorescence microscopy. As a result, the RCTNPs specifically bound to the membrane of NIH 3T3 cells and almost saturated after 6 hours incubation. The amount of RCTNPs uptaken by the cells was higher than that of CTNPs, demonstrating the enhancing effect of RGDS peptide conjugation on the intracellular uptake of quantum dots (QDs)
A new dynamic property of human consciousness
As pointed out by William James, "the consciousness is a dynamic process, not a thing" , during which short term integration is succeeded by another differentiated neural state through the continual interplay between the environment, the body, and the brain itself. Thus, the dynamic structure underlying successive states of the brain is important for understanding human consciousness as a process. In order to investigate the dynamic property of human consciousness, we developed a new method to reconstruct a state space from electroencephalogram(EEG), in which a trajectory, reflecting states of consciousness, is constructed based on the global information integration of the brain. EEGs were obtained from 14 subjects received an intravenous bolus of propopol. Here we show that the degree of human consciousness is directly associated with the information integration capacity of gamma wave, which is significantly higher in the conscious state than in the unconscious state. And we found a new time evolutional property of human consciousness. The conscious state showed a lower dimensional dynamic process which changed to a random-like process after loss of consciousness. This characteristic dynamic property, appeared only in the gamma band, might be used as an indicator to distinguish the conscious and unconscious states and also considered as an important fact for the human consciousness model
Propofol Induction Reduces the Capacity for Neural Information Integration: Implications for the Mechanism of Consciousness and General Anesthesia
The cognitive unbinding paradigm suggests that the synthesis of cognitive information is attenuated by general anesthesia. Here, we investigated the functional organization of brain activities in the conscious and anesthetized states, based on characteristic functional segregation and integration of electroencephalography (EEG). EEG recordings were obtained from 14 subjects undergoing induction of general anesthesia with propofol. We quantified changes in mean information integration capacity in each band of the EEG. After induction with propofol, mean information integration capacity was reduced most prominently in the gamma band of the EEG (p=0.0001). Furthermore, we demonstrate that loss of consciousness is reflected by the breakdown of the spatiotemporal organization of gamma waves. Induction of general anesthesia with propofol reduces the capacity for information integration in the brain. These data directly support the information integration theory of consciousness and the cognitive unbinding paradigm of general anesthesia
Electroluminescent devices with function of electro-optic shutter
The polymer-dispersed liquid crystal (PDLC) was used as a dielectric layer of electroluminescent (EL) device to provide multi-function of electroluminescence and electro-optic shutter. A 50 μm-thick PDLC layer was formed between a transparent electrode and a ZnS:Cu phosphor layer. The electro-optic properties of the EL device were not distorted by the introduction of the PDLC layer. The extraction efficiency of luminescence was improved by more than 14% by PDLC layer. The transmittance of the PDLC was also founded not to be degraded significantly by excitation frequency. Therefore, the electroluminescence of the device was ignited by excitation frequency at a given voltage for full transparency of the PDLC. This device has great potential for applications in transparent displays with the function of a privacy window. © 2012 Optical Society of America.1
Luminance enhancement of electroluminescent devices using highly dielectric UV-curable polymer and oxide nanoparticle composite
A flexible hybrid structure electroluminescent (HSEL) device was fabricated from ZnS:Cu phosphor microparticles dispersed in a UVcurable polymer matrix. We observed a maximum luminance of 111 cd/m2 at 10 kHz and 170 V from a device wherein the mixing ratio between the phosphor particles and highly dielectric polymer binder was 70:30 wt%. Furthermore, by uniformly dispersing highly dielectric BaTiO3 nanoparticles within the polymer matrix, we were able to obtain a luminance of up to 211 cd/m2 in the HSEL device. Compared to the conventional thermal curing process, this UV process greatly simplifies the fabrication steps by combining phosphors and dielectric materials at room temperature. This process also demonstrates a promising pathway toward creating flexible and printed EL devices in the future. © 2014 Optical Society of America.1
Development of Pseudomembranous Colitis Four Months after Initiation of Rifampicin
Pseudomembranous colitis (PMC) may develop with long-term antibiotic administration, but is rarely reported to be caused by antitubercular agents. We present a case of PMC that occurred 120 days after starting rifampicin. A 74-year-old man was diagnosed with pulmonary tuberculosis and started on a standard HERZ regimen (isoniazid, ethambutol, rifampicin, pyrazinamide). After 4 months of HERZ, he presented with frequent bloody, mucoid, jelly-like diarrhea and lower abdominal pain. Sigmoidoscopy revealed multiple whitish plaques with edematous mucosa that were compatible with PMC. Biopsies from these lesions showed ulcer-related necrotic and granulation tissue. We stopped antitubercular treatment and started the patient on oral metronidazole. His symptoms completely resolved within 2 weeks. Antitubercular treatment was restarted by replacing rifampicin with levofloxacin. The patient did not present with diarrhea or bloody stool throughout the rest of treatment
Efficacy evaluation of combination vaccine of recombinant C-terminal fragments of ApxIA, ApxIIA and ApxIIIA in piglets
The efficacy of the combination vaccine of the individual C-terminal fragments of ApxIA, ApxIIA and ApxIIIA of Actinobacillus pleuropneumoniae (APP) was evaluated in piglets. Twenty piglets were divided equally into 2 groups (n=10). All piglets were intramuscularly primed at 4 week-of-age (0 week post prime inoculation (WPPI)) and were intramuscularly boosted at 6 week-of-age (2 WPPI). Group A piglets were inoculated with sterile PBS and group B piglets were inoculated with the combination vaccine. Concentrations of each of the C-terminal fragment-specific IgG as determined by ELISA were significantly higher in group B than in group A from 2 WPPI until the end of this study. Clinical signs were observed from only 10% of group B piglets after the challenge with the mixture of APP serotypes 1, 2 and 5 at 4 WPPI, while 50% of group A piglets were protected against APP infections. Overall, intramuscular inoculation with the vaccine candidate can efficiently protect piglets against APP infection
Electrically tunable birefringence of a polymer composite with long-range orientational ordering of liquid crystals
We report an optical film with electrically tunable birefringence in which the liquid crystals (LCs), mixed with the host polymer, form longrange ordering. The film was prepared through polymerization without phase separation between the LCs and polymers. Driving voltage below 30 V for full switching of birefringence is achieved in a 6 μm-thick film. Electro-optical investigations for the film suggest that the long-range ordering of the LCs mixed in the film caused by polymerization lead to rotations of the LCs as well as optical anisotropy in the film. These films with electrically tunable birefringence could have applications as flexible light modulators and phase retardation films for 2D-3D image switching. © 2014 Optical Society of America.1
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