Single-Step Fast Tissue Clearing of Thick Mouse Brain Tissue for Multi-Dimensional High-Resolution Imaging

Recent advances in optical clearing techniques have dramatically improved deep tissue imaging by reducing the obscuring effects of light scattering and absorption. However, these optical clearing methods require specialized equipment or a lengthy undertaking with complex protocols that can lead to sample volume changes and distortion. In addition, the imaging of cleared tissues has limitations, such as fluorescence bleaching, harmful and foul-smelling solutions, and the difficulty of handling samples in high-viscosity refractive index (RI) matching solutions. To address the various limitations of thick tissue imaging, we developed an Aqueous high refractive Index matching and tissue Clearing solution for Imaging (termed AICI) with a one-step tissue clearing protocol that was easily made at a reasonable price in our own laboratory without any equipment. AICI can rapidly clear a 1 mm thick brain slice within 90 min with simultaneous RI matching, low viscosity, and a high refractive index (RI = 1.466), allowing the imaging of the sample without additional processing. We compared AICI with commercially available RI matching solutions, including optical clear agents (OCAs), for tissue clearing. The viscosity of AICI is closer to that of water compared with other RI matching solutions, and there was a less than 2.3% expansion in the tissue linear morphology during 24 h exposure to AICI. Moreover, AICI remained fluid over 30 days of air exposure, and the EGFP fluorescence signal was only reduced to ~65% after 10 days. AICI showed a limited clearing of brain tissue >3 mm thick. However, fine neuronal structures, such as dendritic spines and axonal boutons, could still be imaged in thick brain slices treated with AICI. Therefore, AICI is useful not only for the three-dimensional (3D) high-resolution identification of neuronal structures, but also for the examination of multiple structural imaging by neuronal distribution, projection, and gene expression in deep brain tissue. AICI is applicable beyond the imaging of fluorescent antibodies and dyes, and can clear a variety of tissue types, making it broadly useful to researchers for optical imaging applications.     

Extraction of interface states at emitter–base heterojunctions in AlGaAs/GaAs heterostructure bipolar transistors using sub-bandgap photonic excitation

Distribution of interface states at the emitter–base heterojunctions in heterostructure bipolar transistors (HBTs) is characterized by using current–voltage characteristics using sub-bandgap photonic excitation. Sub-bandgap photonic source with a photon energy E_ph which is less than the energy bandgap E_g (E_g,GaAs = 1.42, E_g,AlGaAs = 1.76 eV) of emitter, base, and collector of HBTs, is employed for exclusive excitation of carriers only from the interface states in the photo-responsive energy range at emitter–base heterointerface. The proposed method is applied to an Al_0.3Ga_0.7As/GaAs HBT (A_E = W_E × L_E = 250 × 100 μm²) with E_ph = 0.943 eV and P_opt = 3 mW. Extracted interface trap density D_it was observed to be D_it,max  4.2 × 10¹² eV⁻¹ cm⁻² at emitter–base heterointerface.     

Routing Protocol for Heterogeneous Hierarchical Wireless Multimedia Sensor Networks

Recently, wireless multimedia sensor networks (WMSNs) have emerged as one of the most important technologies, driven by the development of powerful multimedia device such as CMOS. WMSNs require several factors such as resource constraints, specific QoS, high bandwidth and so on. In this paper, we propose a hierarchical heterogeneous network model based routing protocol for WMSNs. In our proposal, proposed network model is classified into monitoring class, delivery class and aggregation class. Also we define two kinds of the routing path in order to ensure bandwidth and QoS. In simulation results, we illustrate the performance of our proposal.     

A photomosaic image generation method using photo annotation in a social network environment

With the growing use of social networking services, various applications have been developed to utilize their vast capabilities. Photomosaic techniques, which combine many images to create a new rendering of an input image, can benefit from the capabilities of social networks. In this study, we propose a method that generates a photomosaic image by considering social network context. Our algorithm creates a photomosaic that incorporates photos posted by other users in the users network . We enable the matching function to easily select photos from the albums of users who are connected to the owner of the input image, by computing the closeness of those connections. Moreover, our technique allows the photos in the albums of friends who are annotated in the source image to be matched more effectively.     

Effects of electron beam irradiation on microbial inactivation and quality of kimchi paste during storage

The effects of electron beam irradiation on microbial inactivation and quality of noninoculated and inoculated (Listeria monocytogenes) kimchi pastes were examined. Kimchi paste samples were irradiated at doses of 2, 4, 6, 8 and 10 kGy and stored for 21 days at 4 °C. Irradiation (10 kGy) reduced the populations of total aerobic bacteria, lactic acid bacteria, and yeast and moulds in the samples by 1.72, 2.24 and 0.86 log CFU g^?1, respectively, compared to the control. In particular, coliforms were not detected at 8 and 10 kGy, and the population of L. monocytogenes in inoculated samples was significantly decreased by 2.67 log CFU g^?1. Electron beam irradiation delayed the changes in O₂ and CO₂ concentrations, pH, acidity and reducing sugar content observed in kimchi paste during storage. These results suggest that electron beam irradiation can be used to improve the microbiological safety and shelf life of kimchi paste.     

Two additional cases of metformin‐associated encephalopathy in patients with end‐stage renal disease undergoing hemodialysis

We report on two additional cases of metformin‐associated encephalopathy in patients with end‐stage renal disease (ESRD) undergoing hemodialysis. Two patients were seen at our hospital with abnormal neurological signs and symptoms. Magnetic resonance imaging (MRI) revealed the same pattern of high signal intensity in both basal ganglia in T2‐weighted images in the two patients. The two patients had started taking metformin 5 and 6 weeks earlier at the same dose of 1000 mg per day. Metformin was immediately stopped, and regular hemodialysis was conducted. Their signs and symptoms resolved completely after these measures. The high signal intensity in both ganglia in T2‐weighted MRI also disappeared. We should suspect metformin‐induced encephalopathy and withdraw the drug when presented with diabetic patients with chronic kidney disease and neurological signs and symptoms of unknown cause.     

Grafting maleic anhydride onto EVA and effect on the physical and rheological properties of PETG/EVA-g-MAH blends

Maleic anhydride (MAH) was grafted onto ethylene vinyl acetate copolymer (EVA) in the internal mixer in the presence of dicumyl peroxide (DCP), and a prepared reactive compatibilizer, MAH-g-EVA, was blended with Poly (ethylene glycol-co-cyclohexane-1,4-dimethanol terephthalate) (PETG). The gel content determination and element analysis (EA) was performed to confirm the grafting reaction. It was found that grafting reaction of MAH on to EVA could compete with crosslinking reaction of DCP during the modification process. In addition, the introduction of small amount of MAH showed a great effect on reducing gel content by decreasing crosslink reaction. As MAH content increased, grafted MAH concentration increased, whereas the grafting yield decreased. It was also confirmed that MAH-g-EVA acted as a reactive compatibilizer in the blend with PETG, and enhanced compatibility by reacting with the hydroxyl end groups, OH, of PETG. Addition of EVA in the blend leads a plastic deformation of PETG, and MAH had a great effect on enhancing interfacial adhesion resulting in significant increasing of % strain; however, improved compatibility could not be changed much in low strain tensile strength and Young's modulus. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012