Differences in hearing acuity among “normal-hearing” young adults modulate the neural basis for speech comprehension

AbstractIn this paper, we investigate how subtle differences in hearing acuity affect the neural systems supporting speech processing in young adults. Auditory sentence comprehension requires perceiving a complex acoustic signal and performing linguistic operations to extract the correct meaning. We used functional MRI to monitor human brain activity while adults aged 18–41 years listened to spoken sentences. The sentences varied in their level of syntactic processing demands, containing either a subject-relative or object-relative center-embedded clause. All participants self-reported normal hearing, confirmed by audiometric testing, with some variation within a clinically normal range. We found that participants showed activity related to sentence processing in a left-lateralized frontotemporal network. Although accuracy was generally high, participants still made some errors, which were associated with increased activity in bilateral cingulo-opercular and frontoparietal attention networks. A whole-brain regression analysis revealed that activity in a right anterior middle frontal gyrus (aMFG) component of the frontoparietal attention network was related to individual differences in hearing acuity, such that listeners with poorer hearing showed greater recruitment of this region when successfully understanding a sentence. The activity in right aMFGs for listeners with poor hearing did not differ as a function of sentence type, suggesting a general mechanism that is independent of linguistic processing demands. Our results suggest that even modest variations in hearing ability impact the systems supporting auditory speech comprehension, and that auditory sentence comprehension entails the coordination of a left perisylvian network that is sensitive to linguistic variation with an executive attention network that responds to acoustic challenge.</jats:p

Prevention of Pinking, Off-Odor, and Lipid Oxidation in Irradiated Pork Loin Using Double-Packaging

Lipid oxidation, color, volatiles, and sensory evaluation of double-packaged pork loin were determined to establish a modified packaging method that can improve the quality of irradiated pork loins. Vacuum-packaged irradiated samples produced dimethyl sulfide and dimethyl disulfide responsible for irradiation off-odor, whereas lipid oxidation was promoted under aerobic conditions. Exposing doublepackaged irradiated pork to aerobic conditions for 1 to 3 d was effective in controlling both lipid oxidation and irradiation off-odor, regardless of packaging sequence. Sensory panels could distinguish the decrease in irradiation off-odor intensities by modifying packaging method. However, carbon monoxide-heme pigments, responsible for the increased redness by irradiation, were not effectively controlled by double packaging alone

Nanosheet thickness-modulated MoS2 dielectric property evidenced by field-effect transistor performance

We report on the nanosheet-thickness effects on the performance of top-gate MoS2 field-effect transistors (FETs), which is directly related to the MoS2 dielectric constant. Our top-gate nanosheet FETs with 40 nm thin Al2O3 displayed at least an order of magnitude higher mobility than those of bottom-gate nanosheet FETs with 285 nm thick SiO2, benefiting from the dielectric screening by high-k Al2O3. Among the top-gate devices, the single-layered FET demonstrated the highest mobility of similar to 170 cm(2) V-1 s(-1) with 90 mV dec(-1) as the smallest subthreshold swing (SS) but the double-and triple-layered FETs showed only similar to 25 and similar to 15 cm(2) V-1 s(-1) respectively with the large SS of 0.5 and 1.1 V dec(-1). Such property degradation with MoS2 thickness is attributed to its dielectric constant increase, which could rather reduce the benefits from the top-gate high-k dielectric.open115353Nsciescopu

Development of KAISTSAT-4 Expanding the Role of Small Satellite for Scientific Research

The fourth Korean small satellite, KAISTSAT-4, is under development by Satellite Technology Research Center (SaTReC) of the Korea Advanced Institute of Science and Technology (KAIST). The KAISTSAT-4 program was commenced on October 1998 with multiple mission objectives, which include exploring space science, deploying satellite-based data collection system and development of precision star sensor. Despite severe constraints on mass and size, these advanced science and engineering payloads are expected to deliver various useful results and exhibit the unique role of small satellite. We present an overview of the KAISTSAT-4 mission and describe its current status. Finally the prospect of future small satellite programs is briefly introduced