Imidazolium Polyesters: Structure–Property Relationships in Thermal Behavior,Ionic Conductivity,and Morphology

New bis(ω‐hydroxyalkyl)imidazolium and 1,2‐bis[N‐(ω‐hydroxyalkyl)imidazolium]ethane salts are synthesized and characterized; most of the salts are room temperature ionic liquids. These hydroxyl end‐functionalized ionic liquids are polymerized with diacid chlorides, yielding polyesters containing imidazolium cations embedded in the main chain. By X‐ray scattering, four polyesters are found to be semicrystalline at room temperature: mono‐imidazolium‐C₁₁‐sebacate‐C₆ ( 4e ), mono‐imidazolium‐C₁₁‐sebacate‐C₁₁ ( 4c ), bis(imidazolium)ethane‐C₆‐sebacate‐C₆ ( 5a ), and bis(imidazolium)ethane‐C₁₁‐sebacate‐C₁₁ ( 5c ), all with hexafluorophosphate counterions. The other imidazolium polyesters, including all those with bis(trifluoromethanesulfonyl)imide (TFSI^?) counterions, are amorphous at room temperature. Room temperature ionic conductivities of the mono‐imidazolium polyesters (4 × 10^?6 to 3 × 10^?5 S cm^?1) are higher than those of the corresponding bis‐imidazolium polyesters (4 × 10^?9 to 8 × 10^?6 S cm^?1), even though the bis‐imidazolium polyesters have higher ion concentrations. Counterions affect ionic conduction significantly; all polymers with TFSI^? counterions have higher ionic conductivities than the hexafluorophosphate analogs. Interestingly, the hexafluorophosphate polyester, 1,2‐bis(imidazolium)ethane‐C₁₁‐sebacate‐C₁₁ ( 5c ), displays almost 400‐fold higher room temperature ionic conductivity (1.6 × 10^?6 S cm^?1) than the 1,2‐bis(imidazolium)ethane‐C₆‐sebacate‐C₆ analog ( 5a , 4.3 × 10^?9 S cm^?1), attributable to the differences in the semicrystalline structure in 5c as compared to 5a . These results indicate that semicrystalline polymers may result in high ionic conductivity in a soft (low glass tranition temperature, T_g) amorphous phase and good mechanical properties of the crystalline phase.     

Plasma Aldo-Keto Reductase Family 1 Member B10 as a Biomarker Performs Well in the Diagnosis of Nonalcoholic Steatohepatitis and Fibrosis

We found several blood biomarkers through computational secretome analyses, including aldo-keto reductase family 1 member B10 (AKR1B10), which reflected the progression of nonalcoholic fatty liver disease (NAFLD). After confirming that hepatic AKR1B10 reflected the progression of NAFLD in a subgroup with NAFLD, we evaluated the diagnostic accuracy of plasma AKR1B10 and other biomarkers for the diagnosis of nonalcoholic steatohepatitis (NASH) and fibrosis in replication cohort. We enrolled healthy control subjects and patients with biopsy-proven NAFLD (n = 102) and evaluated the performance of various diagnostic markers. Plasma AKR1B10 performed well in the diagnosis of NASH with an area under the receiver operating characteristic (AUROC) curve of 0.834 and a cutoff value of 1078.2 pg/mL, as well as advanced fibrosis (AUROC curve value of 0.914 and cutoff level 1078.2 pg/mL), with further improvement in combination with C3. When we monitored a subgroup of obese patients who underwent bariatric surgery (n = 35), plasma AKR1B10 decreased dramatically, and 40.0% of patients with NASH at baseline showed a decrease in plasma AKR1B10 levels to below the cutoff level after the surgery. In an independent validation study, we proved that plasma AKR1B10 was a specific biomarker of NAFLD progression across varying degrees of renal dysfunction. Despite perfect correlation between plasma and serum levels of AKR1B10 in paired sample analysis, its serum level was 1.4-fold higher than that in plasma. Plasma AKR1B10 alone and in combination with C3 could be a useful noninvasive biomarker for the diagnosis of NASH and hepatic fibrosis.     

Assessment of Metals Loading in an Acid Mine Drainage Watershed

Watershed-scale modeling can be useful in identifying the main environmental factors and the physical mechanisms responsible for acid mine drainage (AMD) formation, attenuation, and impacts. Since flow rates and water quality of the AMD and receiving streams are related to the rainfall-runoff relationship and associated contaminant dissolution, we thought that hydrologic analysis of the mined area and surrounding drainage basin should be the starting point in documenting the source and fate of AMD contaminants. Further modeling of AMD pollutants could then be performed in terms of metal concentrations and loading at the watershed scale. In this study, monitoring was conducted in the Geopung mine watershed; the watershed analysis risk management framework (WARMF) model was used to evaluate the effect of AMD contributions to downstream metal concentrations. The hydrologic model of the basin was calibrated and verified with rainfall and streamflow data, and the water quality model was calibrated for the dissolved concentrations of metals (Cd, Cu, Zn, and Pb), using discharge data gathered in 2009. There was a strong correlation (r = 0.93) between the observed and simulated runoff values plus high Nash–Sutcliffe model efficiency (NSE = 0.89) and low average percent difference between predicted and measured values (%Diff = 0.46). Subsequent model validation using data gathered in 2010 also showed good agreement (%Diff = 9.76; NSE = 0.77; r = 0.91) between the observed and simulated values. For the metals, the model was calibrated using data from 2010; the correlation between the observed and simulated values was quite good (r = 0.80–0.41).     

Bandwidth-Efficient Transmission Method for User View-Oriented Video Services

The trend in video viewing has been evolving beyond simply providing a multiview option. Recently, a function that allows selection and viewing of a clip from a multiview service that captures a specific range or object has been added. In particular, the freeview service is an extended concept of multi-view and provides a freer viewpoint. However, since numerous videos and additional data are required for its construction, all of the clips constituting the content cannot be simultaneously provided. Only certain clips are selected and provided to the user. If the video is not the preferred video, change request is made, and a delay occurs during retransmission from the server. Delays due to frequent rerequests degrade the overall quality of service. For free-view services, selectively transmitting the video according to the user’s desired viewpoint and region of interest within the limited network of available videos is important. In this study, we propose a method of screening and providing the correct video based on objects in the contents. Based on the method of recognizing the object in each clip, we designed a method of setting its priority based on information about the object’s location for each viewpoint. During the transmission and receiving process using this information, the selected video can be rapidly recognized and changed. Herein, we present a service system configuration method and propose video selection examples for free-view services.     

Exercise Pills for Drug Addiction: Forced Moderate Endurance Exercise Inhibits Methamphetamine-Induced Hyperactivity through the Striatal Glutamatergic Signaling Pathway in Male Sprague Dawley Rats

Physical exercise reduces the extent, duration, and frequency of drug use in drug addicts during the drug initiation phase, as well as during prolonged addiction, withdrawal, and recurrence. However, information about exercise-induced neurobiological changes is limited. This study aimed to investigate the effects of forced moderate endurance exercise training on methamphetamine (METH)-induced behavior and the associated neurobiological changes. Male Sprague Dawley rats were subjected to the administration of METH (1 mg/kg/day, i.p.) and/or forced moderate endurance exercise (treadmill running, 21 m/min, 60 min/day) for 2 weeks. Over the two weeks, endurance exercise training significantly reduced METH-induced hyperactivity. METH and/or exercise treatment increased striatal dopamine (DA) levels, decreased p(Thr308)-Akt expression, and increased p(Tyr216)-GSK-3β expression. However, the phosphorylation levels of Ser9-GSK-3β were significantly increased in the exercise group. METH administration significantly increased the expression of NMDAr1, CaMKK2, MAPKs, and PP1 in the striatum, and exercise treatment significantly decreased the expression of these molecules. Therefore, it is apparent that endurance exercise inhibited the METH-induced hyperactivity due to the decrease in GSK-3β activation by the regulation of the striatal glutamate signaling pathway.     

A study on heatsink fin wave optimization for climate control seat

This research optimizes a heatsink fin wave that improves the cooling and heating efficiency in a Climate control seat (CCS). The design of existing CCS considers the occupant’s pressure, duct shape, blower blade shape, blower cogging torque, and mesh nozzles. However, the heatsink fin wave shape is overlooked in spite of its outstanding thermal efficiency. To address such problems, this research optimized the shape of the heatsink by defining the wave pitch, height pitch, and fin pitch. Parametric analysis (PA) was used such that the effective decision of the variables could be selected within each range of the variances. As a result, the cooling and the heating system operated more efficiently and the time required to reach the target temperature was reduced when compared to the existing system. The performance of the CCS was demonstrated by simulations and experiments.

     

Software-defined radio receiver: dream to reality

This article describes a fully integrated 90 nm CMOS software-defined radio receiver operating in the 800 MHz to 5 GHz band. Unlike the classical SDR paradigm, which digitizes the whole spectrum uniformly, this receiver acts as a signal conditioner for the analog-to-digital converters, emphasizing only the wanted channel. Thus, the ADCs operate with modest resolution and sample rate, consuming low power. This approach makes portable SDR a reality.     

Deep latent-space sequential skill chaining from incomplete demonstrations

Intelligent Service Robotics - Imitation learning is a methodology, which trains an agent using demonstrations from skilled experts without external rewards. However, for a complex task with a long...     

Functional Polysaccharide Sutures Prepared by Wet Fusion of Interfacial Polyelectrolyte Complexation Fibers

This study reports polysaccharide‐based fibers that can be utilized as biocompatible functional sutures. Fibers are spontaneously formed by spinning at the interface between two oppositely charged polysaccharide solutions. Unlike the common belief that polysaccharide fibers prepared by electrostatic interactions would exhibit weak mechanical strength, it is demonstrated that fibers spun at the interface between two droplets of positively charged chitosan and negatively charged heparin can exhibit high mechanical strength through spontaneous wet‐state fusion of interfiber strands at a spinning wheel. Dry solidification results in multistranded fibers that were ≈100 µm in diameter with a tensile strength of ≈220 MPa. Post fibrous manipulation yields various morphology with straight or twisted fibers, fabrics, or springs. To demonstrate application of the fiber, it is applied as a medical suture. As heparin has a unique ability to bind adeno‐associated virus (AAV), a therapeutic, biocompatible suture exhibiting localized AAV‐mediated gene delivery function can be prepared. This study shows that multistrand fusion of fibers, formed by weak, electrostatic interactions and followed by drying solidification counterintuitively results in mechanically strong, functional fibers with various potential applications.     

Recent Advances in Transparent Electronics with Stretchable Forms

Advances in materials science and the desire for next‐generation electronics have driven the development of stretchable and transparent electronics in the past decade. Novel applications, such as smart contact lenses and wearable sensors, have been introduced with stretchable and transparent form factors, requiring a deeper and wider exploration of materials and fabrication processes. In this regard, many research efforts have been dedicated to the development of mechanically stretchable, optically transparent materials and devices. Recent advances in stretchable and transparent electronics are discussed herein, with special emphasis on the development of stretchable and transparent materials, including substrates and electrodes. Several representative examples of applications enabled by stretchable and transparent electronics are presented, including sensors, smart contact lenses, heaters, and neural interfaces. The current challenges and opportunities for each type of stretchable and transparent electronics are also discussed.