Are Language learning websites special? Towards a research agenda for discipline-specific usability

With the intention of defining an initial research agenda for discipline-specific factors in the usability of e-learning websites, this paper focuses on the example of foreign language learning. First, general notions and concepts of usability are analyzed, and the term 'pedagogical usability' is proposed as a means of focusing on the close relationship between usability and pedagogical design. Then, to address the key issue of whether there are aspects of pedagogical usability that are discipline-specific, the paper examines how language learning and teaching, in particular Technology Enhanced Language Learning (TELL), has approached usability when developing technology-enhanced learning materials. Three elements of a research agenda are identified: pedagogical usability, intercultural usability and website evaluation. In conclusion, it is suggested that just as language learning websites may require a discipline-specific approach, so in other disciplines pedagogical usability may also need to be considered in relation to the specific requirements of the discipline, and that a debate around these issues is timely

Sign language development in deaf children with additional needs

This chapter focuses on atypical patterns of sign language development in deaf children. The issue is complicated by the need to differentiate between delays that are due to limited exposure to language, and delays due to health, educational or social difficulties. Sign language acquisition is often delayed in deaf children due to a variety of factors. Between 90-95% of deaf children are from hearing families (Mitchell and Karchmer, 2004). Although many such children eventually become proficient users of a sign language, they frequently experience delayed and impoverished sign language exposure at the crucial early stages of language development and throughout their school years, since hearing parents and professionals are often unable to provide fluent sign language, models (Lu, Jones & Morgan, 2016). Children raised in these environments can acquire some signing skills, and in extreme cases where no signs are used by parents, may even develop systematic, rule-governed gestural systems (Goldin Meadow, Mylander & Franklin, 2007). However, full mastery of the grammar, vocabulary and pragmatics of sign language is a challenge. By contrast, children raised in environments where sign is the first language (i.e., where one or both parents are deaf) typically follow the expected trajectory of development, unless they have an additional learning need

Proposed Global Stratotype Sections and Points for the bases of the Selandian and Thanetian stages (Paleocene Series)

Prepared for the International Subcommission on Paleogene Stratigraph

Rapidly Solidified Sm–Co–V Nanocomposite Permanent Magnets

Alloys around the Sm–Co eutectic composition provide an opportunity to form two-phase nanocomposite permanent magnets consisting of nanoscale Co fibers embedded in Sm2Co17.While ternary alloying elements may refine the scale of the structure, they may also disrupt the eutectic growth and lead to the formation of primary Co. Thus, microstructural selection maps were constructed for conventionally solidified Sm–Co–V alloys. It was found that V additions enlarged the primary Sm2Co17-forming region and, at (Sm0.09Co0.91)97 V3, resulted in a eutectic structure. Upon rapid solidification, this alloy was determined to have a coercivity of 5 kOe with a high remanent ratio. However, the V addition reduced the magnetization, which limited the energy product to 4.3 MG Oe. The rapidly solidified structure consisted of primary SmCo7 dendrites along with an intergranular Co region, suggesting that eutectic structure formation is skewed by underlying metastable phase relationships

Rapidly Solidified Sm–Co–V Nanocomposite Permanent Magnets

Alloys around the Sm–Co eutectic composition provide an opportunity to form two-phase nanocomposite permanent magnets consisting of nanoscale Co fibers embedded in Sm2Co17.While ternary alloying elements may refine the scale of the structure, they may also disrupt the eutectic growth and lead to the formation of primary Co. Thus, microstructural selection maps were constructed for conventionally solidified Sm–Co–V alloys. It was found that V additions enlarged the primary Sm2Co17-forming region and, at (Sm0.09Co0.91)97 V3, resulted in a eutectic structure. Upon rapid solidification, this alloy was determined to have a coercivity of 5 kOe with a high remanent ratio. However, the V addition reduced the magnetization, which limited the energy product to 4.3 MG Oe. The rapidly solidified structure consisted of primary SmCo7 dendrites along with an intergranular Co region, suggesting that eutectic structure formation is skewed by underlying metastable phase relationships

Spontaneous Chelation-Driven Reduction of the Neptunyl Cation in Aqueous Solution.

Octadentate hydroxypyridinone (HOPO) and catecholamide (CAM) siderophore analogues are known to be efficacious chelators of the actinide cations, and these ligands are also capable of facilitating both activation and reduction of actinyl species. Utilizing X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopies, as well as cyclic voltammetry measurements, herein, we elucidate chelation-based mechanisms for driving reactivity and initiating redox processes in a family of neptunyl-HOPO and CAM complexes. Based on the selected chelator, the ability to control the oxidation state of neptunium and the speed of reduction and concurrent oxo group activation was demonstrated. Most notably, reduction kinetics for the NpV O2 +/ /NpIV redox couple upon chelation by the ligands 3,4,3-LI(1,2-HOPO) and 3,4,3-LI(CAM)2 (1,2-HOPO)2 was observed to be faster than ever reported, and in fact quicker than we could measure using either X-ray absorption spectroscopy or electrochemical techniques

Hyperinsulinism-hyperammonaemia syndrome: novel mutations in the GLUD1 gene and genotype-phenotype correlations

Background: Activating mutations in the GLUD1 gene (which encodes for the intra-mitochondrial enzyme glutamate dehydrogenase, GDH) cause the hyperinsulinism–hyperammonaemia (HI/HA) syndrome. Patients present with HA and leucine-sensitive hypoglycaemia. GDH is regulated by another intra-mitochondrial enzyme sirtuin 4 (SIRT4). Sirt4 knockout mice demonstrate activation of GDH with increased amino acid-stimulated insulin secretion. Objectives: To study the genotype–phenotype correlations in patients with GLUD1 mutations. To report the phenotype and functional analysis of a novel mutation (P436L) in the GLUD1 gene associated with the absence of HA. Patients and methods: Twenty patients with HI from 16 families had mutational analysis of the GLUD1 gene in view of HA (n=19) or leucine sensitivity (n=1). Patients negative for a GLUD1 mutation had sequence analysis of the SIRT4 gene. Functional analysis of the novel P436L GLUD1 mutation was performed. Results: Heterozygous missense mutations were detected in 15 patients with HI/HA, 2 of which are novel (N410D and D451V). In addition, a patient with a normal serum ammonia concentration (21 µmol/l) was heterozygous for a novel missense mutation P436L. Functional analysis of this mutation confirms that it is associated with a loss of GTP inhibition. Seizure disorder was common (43%) in our cohort of patients with a GLUD1 mutation. No mutations in the SIRT4 gene were identified. Conclusion: Patients with HI due to mutations in the GLUD1 gene may have normal serum ammonia concentrations. Hence, GLUD1 mutational analysis may be indicated in patients with leucine sensitivity; even in the absence of HA. A high frequency of epilepsy (43%) was observed in our patients with GLUD1 mutations