Environmental Enrichment Enhances Cav 2.1 Channel-Mediated Presynaptic Plasticity in Hypoxic–Ischemic Encephalopathy

Hypoxic–ischemic encephalopathy (HIE) is a devastating neonatal brain condition caused by lack of oxygen and limited blood flow. Environmental enrichment (EE) is a classic paradigm with a complex stimulation of physical, cognitive, and social components. EE can exert neuroplasticity and neuroprotective effects in immature brains. However, the exact mechanism of EE on the chronic condition of HIE remains unclear. HIE was induced by a permanent ligation of the right carotid artery, followed by an 8% O₂ hypoxic condition for 1 h. At 6 weeks of age, HIE mice were randomly assigned to either standard cages or EE cages. In the behavioral assessments, EE mice showed significantly improved motor performances in rotarod tests, ladder walking tests, and hanging wire tests, compared with HIE control mice. EE mice also significantly enhanced cognitive performances in Y-maze tests. Particularly, EE mice showed a significant increase in Ca_v 2.1 (P/Q type) and presynaptic proteins by molecular assessments, and a significant increase of Ca_v 2.1 in histological assessments of the cerebral cortex and hippocampus. These results indicate that EE can upregulate the expression of the Ca_v 2.1 channel and presynaptic proteins related to the synaptic vesicle cycle and neurotransmitter release, which may be responsible for motor and cognitive improvements in HIE.     

Progressive NO2 Sensors with Rapid Alarm and Persistent Memory-Type Responses for Wide-Range Sensing Using Antimony Triselenide Nanoflakes

Antimony triselenide (Sb₂Se₃) nanoflake-based nitrogen dioxide (NO₂) sensors exhibit a progressive bifunctional gas-sensing performance, with a rapid alarm for hazardous highly concentrated gases, and an advanced memory-type function for low-concentration (<1 ppm) monitoring repeated under potentially fatal exposure. Rectangular and cuboid shaped Sb₂Se₃ nanoflakes, comprising van der Waals planes with large surface areas and covalent bond planes with small areas, can rapidly detect a wide range of NO₂ gas concentrations from 0.1 to 100 ppm. These Sb₂Se₃ nanoflakes are found to be suitable for physisorption-based gas sensing owing to their anisotropic quasi-2D crystal structure with extremely enlarged van der Waals planes, where they are humidity-insensitive and consequently exhibit an extremely stable baseline current. The Sb₂Se₃ nanoflake sensor exhibits a room-temperature/low-voltage operation, which is noticeable owing to its low energy consumption and rapid response even under a NO₂ gas flow of only 1 ppm. As a result, the Sb₂Se₃ nanoflake sensor is suitable for the development of a rapid alarm system. Furthermore, the persistent gas-sensing conductivity of the sensor with a slow decaying current can enable the development of a progressive memory-type sensor that retains the previous signal under irregular gas injection at low concentrations.     

Thermochemical stability of Fe- and co-functionalized perovskite-type SrTiO3 oxygen transport membrane materials in syngas conditions

The materials typically used for oxygen transport membranes, Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3?δ (BSCF) and La_0.6Sr_0.4Co_0.2Fe_0.8O₃ (LSCF) tend to decompose due to their low thermochemical stability under reducing atmosphere. Fe- and Co-doped SrTiO₃ (SrTi_1-x-yCo_xFe_yO_3-δ, x + y ≤ 0.35) (STCF) materials showing an oxygen transport comparable to LSCF have great potential for application in ion-transport-devices. In this study, the thermochemical stability of pure perovskite-structured STCF was investigated after annealing in a syngas atmosphere at 600–900 °C. The phase composition of the materials after annealing was characterized by means of X-ray diffraction (XRD). The thermodynamic activities of SrO, FeO, and CoO in the STCF materials were evaluated using Knudsen effusion mass spectrometry (KEMS). Co-doped SrTiO₃ (STC) materials were not stable after annealing in the syngas atmosphere above 5 mol% Co-substitution. Ruddlesden-Popper-like phases and SrCO₃ were detected after annealing at 600 °C. In contrast, Fe substitution (STF) showed good stability after annealing in syngas upto 35 mol% substitution.     

Aqueous dispersion of 1D van der Waals Mo6S3I6 crystal using biocompatible tri-block copolymer

To achieve the stable dispersion of 1D van der Waals crystal Mo₆S₃I₆ in aqueous media, the tri-block copolymer (Poloxamer) is used as dispersant. The head group of Poloxamer, hydrophobic polypropylene oxide parts can be adsorbed to Mo₆S₃I₆ surface by hydrophobic interaction and the tail group with hydrophilic polyethylene oxide exposed to the outside of the Mo₆S₃I₆ is soluble in water and can form sufficient steric hindrance, resulting in stable aqueous dispersion in nm scale. The excellent biocompatibility of aqueous dispersed nm scale 1D Mo₆S₃I₆ was demonstrated by effective proliferation of C2C12 cells.     

An Intelligent Product Recommendation Model to Reflect the Recent Purchasing Patterns of Customers

Mobile Networks and Applications - This study suggests a new product recommendation model to reflect the recent purchasing patterns of customers. There are many methods to measure the similarity...     

Reliability measure approach for confidence-based design optimization under insufficient input data

Structural and Multidisciplinary Optimization - In most of the reliability-based design optimization (RBDO) researches, accurate input statistical model has been assumed to concentrate on the...     

Computer-based engineering of thermostabilized antibody fragments

We used the molecular modeling program Rosetta to identify clusters of amino acid substitutions in antibody fragments (scFvs and scAbs) that improve global protein stability and resistance to thermal deactivation. Using this methodology, we increased the melting temperature (T_m) and resistance to heat treatment of an antibody fragment that binds to the Clostridium botulinum hemagglutinin protein (anti-HA33). Two designed antibody fragment variants with two amino acid replacement clusters, designed to stabilize local regions, were shown to have both higher T_m compared to the parental scFv and importantly to retain full antigen binding activity after 2 hr of incubation at 70°C. The crystal structure of one thermostabilized scFv variants was solved at 1.6 Å and shown to be in close agreement with the RosettaAntibody model prediction.