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Argumentation plays a significant role in science as a scientific practice in which knowledge is constructed, evaluated, and modified. Scientific argumentation (SA) is thus a promising activity for students to pursue in order to think and act like scientists and to enhance their understanding of science. Considering the impact that assessments usually have on teaching and their role in understanding students' ability, this study aims to explore the assessment of scientific argumentation competence (SAC) and Chinese high school students' performance and perceptions of SA. This study, therefore, proposes a three-component framework for understanding SAC, including the competencies to identify, evaluate, and generate the SA elements outlined in Toulmin's argument model. Based on this framework, we hypothesize three levels of SAC and develop a test including 22 items to see whether these proposed SAC elements are valid and to what extent they represent students' levels of SAC. An iterative procedure is adopted to develop and validate the assessment instrument, validity evidence is collected from the analysis of teachers' interviews, students' think-aloud and follow-up interviews, and from confirmatory factor analysis and Rasch analysis of students' scores on the test. The results suggest that the measure, which includes three SAC components has acceptable reliability and validity, and the three-level progression of SAC is aligned with and further expands previous learning progressions of SA. We also find that most students in our sample are at level 1 of SAC and they in general hold positive attitudes toward learning through argumentation, but their willingness in engaging with SA tends to be affected by their perception of the intrinsic and practical value of SA and their personality. Providing them with explanations of SA elements does not improve their test performance.

Languages vary in their complexity; caregivers vary in the way they structure their communicative interactions with children; and boys and girls can differ in their language skills. Using a multilevel modelling approach, we explored how these factors influence the path of language acquisition for young children growing up around the world (mean age 2‐years 9‐months; 56 girls). Across 43 different sites, we analysed 103 mother–child pairs who spoke 3,170,633 utterances, 16,209,659 morphemes, divided across 20 different languages: Afrikaans, Catalan, Cantonese, Danish, Dutch, English, Farsi, French, German, Hebrew, Icelandic, Irish, Italian, Japanese, Mandarin, Norwegian, Portuguese, Spanish, Swedish and Turkish. Using mean length of utterance (MLU) as a measure of language complexity and developmental skill, we found that variation in children's MLU was significantly explained by (a) between‐language differences; namely the rate of child MLU growth was attuned to the complexity of their mother tongue, and (b) between‐mother differences; namely mothers who used higher MLUs tended to have children with higher MLUs, regardless of which language they were learning and especially in the very young (<2.5 years‐old). Controlling for family and language environment, we found no evidence of MLU sex differences in child speech nor in the speech addressed to boys and girls. By modelling language as a multilevel structure with cross‐cultural variation, we were able to disentangle those factors that make children's pathway to language different and those that make it alike. Research Highlights: The speech of 103 mother–child pairs from 20 different languages showed large variation in the path of early language development.Language, family, but not the sex of the child, accounted for a significant proportion of individual differences in child speech, especially in the very young.The rate at which children learned language was attuned to the complexity of their mother tongue, with steeper trajectories for more complex language.Results demonstrate the relative influence of culture, family, and sex in shaping the path of language acquisition for different children. [ABSTRACT FROM AUTHOR]

Hox genes play crucial roles in establishing regional identity along the anterior-posterior axis in bilaterian animals, and have been implicated in generating morphological diversity throughout evolution. Here we report the identification, expression, and initial genomic characterization of the complete set of Hox genes from the amphipod crustacean Parhyale hawaiensis. Parhyale is an emerging model system that is amenable to experimental manipulations and evolutionary comparisons among the arthropods. Our analyses indicate that the Parhyale genome contains a single copy of each canonical Hox gene with the exception of fushi tarazu, and preliminary mapping suggests that at least some of these genes are clustered together in the genome. With few exceptions, Parhyale Hox genes exhibit both temporal and spatial colinearity, and expression boundaries correlate with morphological differences between segments and their associated appendages. This work represents the most comprehensive analysis of Hox gene expression in a crustacean to date, and provides a foundation for functional studies aimed at elucidating the role of Hox genes in arthropod development and evolution.

Allergies affect approximately 10–30% of people worldwide, with an increasing number of cases each year; however, the underlying mechanisms are still poorly understood. In recent years, extracellular vesicles (EVs) have been suggested to play a role in allergic sensitization and skew to a T helper type 2 (Th2) response. The aim of this review is to highlight the existing evidence of EV involvement in allergies. A total of 22 studies were reviewed; 12 studies showed EVs can influence a Th2 response, while 10 studies found EVs promoted a Th1 or Treg response. EVs can drive allergic sensitization through up-regulation of pro-Th2 cytokines, such as IL-4 and IL-13. In addition, EVs from MRSA can induce IgE hypersensitivity in mice towards MRSA. On the other hand, EVs can induce tolerance in the immune system; for example, pre-exposing OVA-loaded EVs prevented OVA sensitization in mice. The current literature thus suggests that EVs play an essential role in allergy. Further research utilizing human in vitro models and clinical studies is needed to give a reliable account of the role of EVs in allergy. [ABSTRACT FROM AUTHOR]

Transmission of an airborne disease can occur when an individual exhales respiratory particles that contain infectious pathogens. Surgical face masks are often used to reduce the amount of respiratory aerosol emitted into the environment by an individual while also lowering the concentration of particles the individual inhales. Respiratory aerosol generation is activity-dependent with high person-to-person variability. Moreover, mask fit differs among people. Here, we measure the efficacy of surgical masks (EN14683 Type IIR) in reducing both aerosol (0.3 − 20 µm diameter) and droplet (20 − 1000 µm diameter) emission during breathing, speaking and five speech and language therapy tasks performed by a human cohort. When participants wore a surgical face mask, measured particle number concentrations at the front of the mask were always lower than that for breathing without mitigation in place. For breathing and speaking, the through-mask filtration efficiencies were 80% and 87%, respectively, while for voice therapy tasks the through-mask filtration efficiencies ranged from 89% ("Hey!") to 95% (/a::/). Size-dependent through-mask filtration efficiencies were high (80 – 95%) for particles 0.5 − 2 µm diameter, with masks filtering a greater fraction of larger particle sizes. For particle sizes >4 µm diameter, filtration efficiencies of surgical face masks for all tested respiratory tasks were ∼100%. Surgical face masks significantly reduced the number of particles emitted from all respiratory activities. These results have implications for developing effective mitigations for disease transmission through inhalation. [ABSTRACT FROM AUTHOR]

The cluster of differentiation 36 (CD36) domain defines the characteristic ectodomain associated with class B scavenger receptor (SR-B) proteins. In bilaterians, SR-Bs play critical roles in diverse biological processes including innate immunity functions such as pathogen recognition and apoptotic cell clearance, as well as metabolic sensing associated with fatty acid uptake and cholesterol transport. Although previous studies suggest this protein family is ancient, SR-B diversity across Eukarya has not been robustly characterized. We analyzed SR-B homologs identified from the genomes and transcriptomes of 165 diverse eukaryotic species. The presence of highly conserved amino acid motifs across major eukaryotic supergroups supports the presence of a SR-B homolog in the last eukaryotic common ancestor. Our comparative analyses of SR-B protein structure identify the retention of a canonical asymmetric beta barrel tertiary structure within the CD36 ectodomain across Eukarya. We also identify multiple instances of independent lineage-specific sequence expansions in the apex region of the CD36 ectodomain—a region functionally associated with ligand-sensing. We hypothesize that a combination of both sequence expansion and structural variation in the CD36 apex region may reflect the evolution of SR-B ligand-sensing specificity between diverse eukaryotic clades. [ABSTRACT FROM AUTHOR]