83 research outputs found
Learning a second language in adulthood changes subcortical neural encoding
Second language learning has been shown to impact and reshape the central nervous system, anatomically and functionally. Most of the studies on second language learning and neuroplasticity have been focused on cortical areas, whereas the subcortical neural encoding mechanism and its relationship with L2 learning have not been examined extensively. The purpose of this study was to utilize frequency-following response (FFR) to examine if and how learning a tonal language in adulthood changes the subcortical neural encoding in hearing adults. Three groups of subjects were recruited: native speakers of Mandarin Chinese (native speakers (NS)), learners of the language (L2 learners), and those with no experience (native speakers of foreign languages (NSFL)). It is hypothesized that differences would exist in FFRs obtained from the three language experience groups. Results revealed that FFRs obtained from L2 learners were found to be more robust than the NSFL group, yet not on a par with the NS group. Such results may suggest that in human adulthood, subcortical neural encoding ability may be trainable with the acquisition of a new language and that neuroplasticity at the brainstem level can indeed be influenced by L2 learning
Host-Guest Complexation of Amphiphilic Molecules at the Air-Water Interface Prevents Oxidation by Hydroxyl Radicals and Singlet Oxygen
The oxidation of antioxidants by oxidizers imposes great challenges to both living organisms and the food industry. Here we show that the hostâguest complexation of the carefully designed, positively charged, amphiphilic guanidinocalix[5]arene pentadodecyl ether (GC5Aâ12C) and negatively charged oleic acid (OA), a wellâknown cell membrane antioxidant, prevents the oxidation of the complex monolayers at the airâwater interface from two potent oxidizers hydroxyl radicals (OH) and singlet delta oxygen (SDO). OH is generated from the gas phase and attacks from the top of the monolayer, while SDO is generated inside the monolayer and attacks amphiphiles from a lateral direction. Fieldâinduced droplet ionization mass spectrometry results have demonstrated that the hostâguest complexation achieves steric shielding and prevents both types of oxidation as a result of the tight and âsleeved inâ physical arrangement, rather than the chemical reactivity, of the complexes
Host-Guest Complexation of Amphiphilic Molecules at the Air-Water Interface Prevents Oxidation by Hydroxyl Radicals and Singlet Oxygen
The oxidation of antioxidants by oxidizers imposes great challenges to both living organisms and the food industry. Here we show that the hostâguest complexation of the carefully designed, positively charged, amphiphilic guanidinocalix[5]arene pentadodecyl ether (GC5Aâ12C) and negatively charged oleic acid (OA), a wellâknown cell membrane antioxidant, prevents the oxidation of the complex monolayers at the airâwater interface from two potent oxidizers hydroxyl radicals (OH) and singlet delta oxygen (SDO). OH is generated from the gas phase and attacks from the top of the monolayer, while SDO is generated inside the monolayer and attacks amphiphiles from a lateral direction. Fieldâinduced droplet ionization mass spectrometry results have demonstrated that the hostâguest complexation achieves steric shielding and prevents both types of oxidation as a result of the tight and âsleeved inâ physical arrangement, rather than the chemical reactivity, of the complexes
A high-precision bidirectional time-transfer system over a single fiber based on wavelength-division multiplexing and time-division multiplexing
In this paper, a high-precision bidirectional time-transfer system over a single fiber based on wavelength-division multiplexing and time-division multiplexing (SFWDM-TDM) is proposed, which combines the advantages of wavelength-division multiplexing and time-division multiplexing. It uses two dense wavelength-division channels to effectively suppress the problem of optical fiber reflection. At the same time, the time-division multiplexing method is used in combination with sampling and holding the time to complete the multi-user task. In hardware, we optimized the carrier processing and the high-precision time-delay control module of the SFWDM-TDM system to complete high-precision time-transfer equipment. In software and algorithm, the optical fiber time-interval measurement method and measurement times are optimized, and the SFWDM-TDM system reaches a synchronization accuracy of 8.9 ps at 1Â s. Finally, a real-time detection mechanism with self-recovery ability is added to the system. This lays the foundation for a reliable, long-distance, high-precision, and multi-user mode optical fiber time- and frequency-transfer network
Genome-wide association study reveals genetic loci and candidate genes for meat quality traits in a four-way crossbred pig population
Meat quality traits (MQTs) have gained more attention from breeders due to their increasing economic value in the commercial pig industry. In this genome-wide association study (GWAS), 223 four-way intercross pigs were genotyped using the specific-locus amplified fragment sequencing (SLAF-seq) and phenotyped for PH at 45Â min post mortem (PH45), meat color score (MC), marbling score (MA), water loss rate (WL), drip loss (DL) in the longissimus muscle, and cooking loss (CL) in the psoas major muscle. A total of 227, 921 filtered single nucleotide polymorphisms (SNPs) evenly distributed across the entire genome were detected to perform GWAS. A total of 64 SNPs were identified for six meat quality traits using the mixed linear model (MLM), of which 24 SNPs were located in previously reported QTL regions. The phenotypic variation explained (PVE) by the significant SNPs was from 2.43% to 16.32%. The genomic heritability estimates based on SNP for six meat-quality traits were low to moderate (0.07â0.47) being the lowest for CL and the highest for DL. A total of 30 genes located within 10Â kb upstream or downstream of these significant SNPs were found. Furthermore, several candidate genes for MQTs were detected, including pH45 (GRM8), MC (ANKRD6), MA (MACROD2 and ABCG1), WL (TMEM50A), CL (PIP4K2A) and DL (CDYL2, CHL1, ABCA4, ZAG and SLC1A2). This study provided substantial new evidence for several candidate genes to participate in different pork quality traits. The identification of these SNPs and candidate genes provided a basis for molecular marker-assisted breeding and improvement of pork quality traits
A Glimpse of Streptococcal Toxic Shock Syndrome from Comparative Genomics of S. suis 2 Chinese Isolates
BACKGROUND: Streptococcus suis serotype 2 (SS2) is an important zoonotic pathogen, causing more than 200 cases of severe human infection worldwide, with the hallmarks of meningitis, septicemia, arthritis, etc. Very recently, SS2 has been recognized as an etiological agent for streptococcal toxic shock syndrome (STSS), which was originally associated with Streptococcus pyogenes (GAS) in Streptococci. However, the molecular mechanisms underlying STSS are poorly understood. METHODS AND FINDINGS: To elucidate the genetic determinants of STSS caused by SS2, whole genome sequencing of 3 different Chinese SS2 strains was undertaken. Comparative genomics accompanied by several lines of experiments, including experimental animal infection, PCR assay, and expression analysis, were utilized to further dissect a candidate pathogenicity island (PAI). Here we show, for the first time, a novel molecular insight into Chinese isolates of highly invasive SS2, which caused two large-scale human STSS outbreaks in China. A candidate PAI of âź89 kb in length, which is designated 89K and specific for Chinese SS2 virulent isolates, was investigated at the genomic level. It shares the universal properties of PAIs such as distinct GC content, consistent with its pivotal role in STSS and high virulence. CONCLUSIONS: To our knowledge, this is the first PAI candidate from S. suis worldwide. Our finding thus sheds light on STSS triggered by SS2 at the genomic level, facilitates further understanding of its pathogenesis and points to directions of development on some effective strategies to combat highly pathogenic SS2 infections
Effect of unsupervised Kinect-based mixed reality fitness programs on health-related fitness in men during COVID-19 pandemic: randomized controlled study
This study aimed to investigate the effect
of Kinect-based mixed reality (KMR) exercise and unsupervised individual exercise
on health-related fitness. A total of 27 participants underwent cardiorespiratory
fitness tests for the inclusion criteria and were randomly assigned to three
groups: a KMR group (KMRG), an unsupervised individual group (UIG), or a control
group (CG). Pre and post-tests were conducted to measure Maximum oxygen uptake
(VOâmax), body composition, upper and lower-body (LB) muscle strength, and
endurance. KMRG and UIG attended exercise sessions 3 days per week for 8 weeks.
KMRG used the KMR device and UIG used an instructive banner for exercise. All
groups maintained their daily routines and submitted diet records every 4 weeks.
Results showed that VOâmax, upper-body muscle endurance, and LB muscle endurance
of knee extension was increased in KMRG and UIG. LB muscle strength in knee
flexion was increased in UIG and LB muscle endurance in knee flexion was
increased in KMRG. VOâmax, LB muscle strength, and LB muscle endurance were
greater in KMRG than in CG. LB muscle strength in knee flexion was greater in
KMRG than in UIG. Body fat was increased and skeletal muscle mass was decreased
in CG. KMR exercise showed better performance than unsupervised individual (UI)
exercise, and the exercise program was effective in both KMR and UI environments.
These findings contribute to the growing evidence supporting the use of
technology-based exercise interventions as a potential strategy to enhance
health-related fitness
Investigation of Testosterone, Androstenone, and Estradiol Metabolism in HepG2 Cells and Primary Culture Pig Hepatocytes and Their Effects on 17βHSD7 Gene Expression
Steroid metabolism is important in various species. The accumulation of androgen metabolite, androstenone, in pig adipose tissue is negatively associated with pork flavor, odour and makes the meat unfit for human consumption. The 17β-hydroxysteroid dehydrogenase type 7 (17βHSD7) expressed abundantly in porcine liver, and it was previously suggested to be associated with androstenone levels. Understanding the enzymes and metabolic pathways responsible for androstenone as well as other steroids metabolism is important for improving the meat quality. At the same time, metabolism of steroids is known to be species- and tissue-specific. Therefore it is important to investigate between-species variations in the hepatic steroid metabolism and to elucidate the role of 17βHSD7 in this process. Here we used an effective methodological approach, liquid chromatography coupled with mass spectrometry, to investigate species-specific metabolism of androstenone, testosterone and beta-estradiol in HepG2 cell line, and pig cultured hepatocytes. Species- and concentration-depended effect of steroids on 17βHSD7 gene expression was also investigated. It was demonstrated that the investigated steroids can regulate the 17βHSD7 gene expression in HepG2 and primary cultured porcine hepatocytes in a concentration-dependent and species-dependent pattern. Investigation of steroid metabolites demonstrated that androstenone formed a 3â˛-hydroxy compound 3β-hydroxy-5Îą-androst-16-ene. Testosterone was metabolized to 4-androstene-3,17-dione. Estrone was found as the metabolite for β-estradiol. Inhibition study with 17βHSD inhibitor apigenin showed that apigenin didn't affect androstenone metabolism. Apigenin at high concentration (50 ÎźM) tends to inhibit testosterone metabolism but this inhibition effect was negligible. Beta-estradiol metabolism was notably inhibited with apigenin at high concentration. The study also established that the level of testosterone and β-estradiol metabolites was markedly increased after co-incubation with high concentration of apigenin. This study established that 17βHSD7 is not the key enzyme responsible for androstenone and testosterone metabolism in porcine liver cells. Š 2012 Chen et al
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