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The ciaRH operon in Streptococcus mutans contains 3 contiguous genes, ciaXRH. Unlike the CiaRH system in other streptococci, only the ciaH-null mutant displays defective phenotypes, while the ciaR-null mutant behaves like the wild type. The objective of this study was to determine the mechanism of this unusual property. We demonstrate that the ciaH mutation caused a >20-fold increase in ciaR transcript synthesis. A ciaRH double deletion reversed the ciaH phenotype, suggesting that overexpressed ciaR might be responsible for the observed ciaH phenotypes. When ciaR was forced to be overexpressed by a transcriptional fusion to the ldh promoter in the wild-type background, the same ciaH phenotypes were restored, confirming the involvement of overexpressed ciaR in the ciaH phenotypes. The ciaH mutation and ciaR overexpression also caused transcriptional alterations in 100 genes, with 15 genes upregulated >5-fold. Bioinformatics analysis identified a putative CiaR regulon consisting of 8 genes/operons, including the ciaXRH operon itself, all of which were upregulated. In vitro footprinting on 4 of the 8 promoters revealed a protected region of 26 to 28 bp encompassing two direct repeats, NTTAAG-n5-WTTAAG, 10 bp upstream of the -10 region, indicating direct binding of the CiaR protein to these promoters. Taken together, we conclude that overexpressed CiaR, as a result of either ciaH deletion or forced expression from a constitutive promoter, is a mediator in the CiaH-regulated phenotypes. doi: 10.1128/JB.00556-10

Streptococcus mutans is considered a primary pathogen for human dental caries. Its ability to produce a variety of peptide antibiotics called mutacins may play an important role in its invasion and establishment in the dental biofilm. S. mutans strain UA140 produces two types of mutacins, the lantibiotic mutacin I and the non-lantibiotic mutacin IV. In a previous study, we constructed a random insertional-mutation library to screen for genes involved in regulating mutacin I production, and found 25 genes/operons that have a positive effect on mutacin I production. In this study, we continued our previous work to identify genes that are negatively involved in mutacin I production. By using a high-phosphate brain heart infusion agar medium that inhibited mutacin I production of the wild-type, we isolated 77 clones that consistently produced mutacin I under repressive conditions. From the 34 clones for which we were able to obtain a sequence, 17 unique genes were identified. These genes encompass a variety of functional groups, including central metabolism, surface binding and sugar transport, and unknown functions. Some of the 17 mutations were further characterized and shown to increase mutacin gene expression during growth when the gene is usually not expressed in the wild-type. These results further demonstrate an intimate and intricate connection between mutacin production and the overall cellular homeostasis.

It is well established that emotion is extensively influenced by language. However, previous studies mainly focus on the first language (L1) rather than the second language (L2). The current study explored whether L2 shapes emotion perception in masked priming paradigm by distinguishing emotion-label words (e.g. fear, pride) and emotion-laden words (e.g. breakup, mother). Twenty-three Chinese-English bilinguals were instructed to judge the valence of the emotional pictures that were followed by masked and briefly presented L2 emotion words. Behavioral results showed that emotional pictures primed by negative emotion-label words were processed faster and more accurate than primed by emotion-laden words. Event-related potential results further revealed that emotional pictures elicited smaller N300 primed by negative emotion-label words than by emotion-laden words. The converging evidence suggests that second language can also modulate emotion perception fast and automatically, and such modulation is dependent on emotion word type. [ABSTRACT FROM AUTHOR]

How emotional language is processed in children with ASD It is generally accepted that children with ASD suffer from both language and emotion deficits ([1]; [12]). Prévost and Tuller (2022, henceforth P & T) provided an insightful and comprehensive literature review on bilingual language development among children with autism spectrum disorders (ASD). Secondly, children with ASD might have different emotional language development trajectories from typically developing children, and how language and emotion are intertwined in children with ASD should be clarified. [Extracted from the article]

Abstract Background Pertussis is a reported vaccine-preventable respiratory disease in China. Because the routine laboratory methods for diagnosis are not in use, the reported cases are mainly in infants with classical paroxysmal cough and the true incidence related to pertussis is most likely under estimated. In China, however, few studies have attempted to address this issue. The purpose of this cross sectional study was to estimate the incidence rates using the method of sero-epidemiology of immunoglobulin (Ig) G antibodies against pertussis toxin (PT) among healthy populations in China. Methods Blood samples were obtained from 1313 healthy individuals aged 0 to 95 years in Guangdong province of China throughout September 2010. Serum IgG antibodies against PT were determined by commercial ELISA kits. Subjects with concentration of anti-PT IgG higher than 30 IU/mL were indicated to have recent Bordetella pertussis infection, if they have not received a booster dose of pertussis vaccine within one year. Results Of the 1313 study subjects, 117 (8.91%) were found to have anti-PT antibodies higher than 30 IU/mL. The estimated incidence of recent infection was thus 9395 per 100,000 for individuals older than 7 years. Peaks of the estimated incidence rate of recent infection were found to be 11561 per 100,000 in age group of 41–50 years and 11428 per 100,000 in the group aged 13–19 years. Conclusions Our study indicated that B.pertussis infections are considerablely common, particularly in adolescents and adults in China. The study also stresses the importance of laboratory diagnosis for pertussis and employment of booster dose of pertussis vaccine in adolescents and adults in this country.

Based on Messick's (1995) framework of construct validity and responses from 521 teachers in the United States and 580 teachers in China, this study provided evidence of the generalizability aspect of construct validity for the Classroom Appraisal of Resources and Demands (CARD) questionnaire originally developed in the United States. Confirmatory factor analysis, factorial invariance testing, and differential item functioning were employed to examine the systematic variation of interpretation by the Chinese and US elementary school teachers with respect to the 65 items in the CARD. Results suggested that responses to CARD follow the same structure from both Chinese and US teachers, and that 83% of items showed no difference. Differences in Chinese and US teachers' interpretations of certain items were discussed with implications to school psychology, school counseling, teacher education, educational administration, and policy research. [ABSTRACT FROM AUTHOR]

Modern cloud providers offer dense hardware with multiple cores and large memories, hosted in global platforms. This raises the challenge of implementing high-performance software systems that can effectively scale from a single core to multicore to the globe. Conventional wisdom says that software designed for one scale point needs to be rewritten when scaling up by 10 − 100× . In contrast, we explore how a system can be architected to scale across many orders of magnitude by design. We explore this challenge in the context of a new key-value store system called Anna: a partitioned, multi-mastered system that achieves high performance and elasticity via wait-free execution and coordination-free consistency. Our design rests on a simple architecture of coordination-free actors that perform state update via merge of lattice-based composite data structures. We demonstrate that a wide variety of consistency models can be elegantly implemented in this architecture with unprecedented consistency, smooth fine-grained elasticity, and performance that far exceeds the state of the art. [ABSTRACT FROM AUTHOR]

In this brief commentary, we propose the emotion word type that has not been elucidated in the review (Hinojosa, J. A., Moreno, E. M., & Ferré, P. (2019). Affective neurolinguistics: Towards a framework for reconciling language and emotion. Language, Cognition and Neuroscience. Advance online publication. doi:10.1080/23273798.2019.1620957) should be incorporated in affective neurolinguistics. Emotion words, as a category against neutral words, are a mixture of two sub types: emotion-label words (e.g. joy, sorrow) and emotion-laden words (e.g. reward, snake). Differences between the two kinds of words have been confirmed in numerous studies. The discrepancy of the two types of words has the potential of contributing to the definition and categorisation of emotion words and provides a new interface for affective neurolinguistics, affective neuroscience, and cognitive neuroscience. [ABSTRACT FROM AUTHOR]

Emotion words modulate conflict processing, even at an early stage (i.e., N200). However, the previous studies implicitly mixed emotion-label words and emotion-laden words together and mostly concentrated on first language (L1) rather than on second language (L2). The current study aimed to investigate whether L2 negative emotion-label words, negative emotion-laden words, and neutral words would affect conflict processing in a flanker task by using event-related potential (ERP) measurements. Twenty Chinese-English bilinguals completed a modified flanker task to decide the color of the target words. The results revealed that only L2 negative emotion-label words elicited larger left frontal N200 in the incongruent condition than in the congruent condition. No significant difference between the two conditions was observed for L2 negative emotion-laden words or neutral words. This research demonstrated that L2 emotion words could also modulate early conflict processing, at least for L2 negative emotion-label words. [ABSTRACT FROM AUTHOR]