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Adolescent reading experience, independent choices and curriculum materials
Get PDFReading comprehension ability is assessed in England within the English language GCSE exam. This is a high stakes exam, taken by all 16-year-olds, and a pass grade is needed to progress onto the next stage of education and employment. Since reading experience is an important predictor of reading comprehension ability, two different types of reading materials were explored to see how well they matched the reading required in the exam: 1) curriculum reading; and 2) independent reading. Two corpora of texts representing the two types of reading were created and explored using the methods of Corpus Linguistics. The curriculum reading corpus (CRC) had lower linguistic diversity, and higher frequency of nouns but lower frequency of adverbs , than the independent reading corpus (IRC. Exploratory analysis of the most frequent parts of speech revealed that the CRC had words that were more abstract and conceptual, whereas the IRC featured words about the concrete and the everyday, suggesting that curriculum reading presents a different type of vocabulary challenge. The CRC was not as close a match to the exam texts as the IRC. As the English language GCSE exam is used as a measure of literacy competency for both future study and future employment, this suggests that the types of texts chosen for the exam are not a good match for this purpose. The choice of texts in assessments therefore needs careful consideration
Norm estimates for the Hilbert matrix operator on weighted Bergman spaces
Get PDFWe study the Hilbert matrix operator H and a related integral operator T acting
on the standard weighted Bergman spaces Ap
α. We obtain an upper bound for T,
which yields the smallest currently known explicit upper bound for the norm of H
for −1 <α< 0 and 2 + α<p< 2(2 + α). We also calculate the essential norm for
all p > 2 + α > 1, extending a part of the main result in [Adv. Math. 408 (2022)
108598] to the standard unbounded weights. It is worth mentioning that except for
an application of Minkowski’s inequality, the norm estimates obtained for T are
sharp
Exploring EFL teachers’ beliefs about strategy, scope and focus in written corrective feedback
Get PDFEffective written feedback is crucial to student learning and developing writing skills. Responding to student writing is a multifaceted and complex process that requires a more nuanced understanding of second language writing research. This study explored teachers’ beliefs and practices about written feedback, which may be influenced by a range of factors. Data were collected from four middle-school English teachers in China via stimulated recall tasks and semi-structured interviews reflecting retrospectively on how and why teachers gave feedback to student writing. Findings revealed intersections between feedback strategy and learner proficiency level; feedback scope and time constraints, including teacher workload; and feedback focus and contextual factors. Additionally, we discuss the implications of these findings in relation to teacher professional development, contextualized teacher education, and the changing landscape of written feedback practices in the age of AI
d10s2 post-transition metal anions: identifying and analyzing their dual-mode Lewis basicity
Get PDFLiquid-phase d10s2 post-transition metal anions, such as [SnCl3]−, appear in a range of applications with a focus on catalysis and material preparation. However, little is known about their electronic structure and how it relates to reactivity. Using X-ray photoelectron spectroscopy and ab initio calculations, we demonstrate that liquid-phase d10s2 post-transition metal anions can act as dual-mode Lewis bases, interacting through the metal center and/or the ligands, with the interaction mode depending on the identity of the Lewis acid/electron acceptor. The Lewis basicity of the metal donor atom is controlled mainly by the metal identity; the ligand can be used for fine-tuning. Changing the metal center has a strong effect on the ligand basicity. These findings provide insight into d10s2 post-transition metal anion electronic structure, which will enable better molecular-level design of catalytic systems
The continued threat of toxic NSAIDs to critically endangered Gyps vultures in South Asia
No full textRapid population declines of three species of Gyps vultures endemic to Asia were caused by unintentional poisoning by the non-steroidal anti-inflammatory drug (NSAID) diclofenac. Despite a ban on its veterinary use across South Asia, diclofenac has continued to be supplied for this purpose. Here, we report updated results from undercover pharmacy surveys, conducted between 2012 and 2024, in India, Nepal, Bangladesh, and Pakistan to investigate the availability and prevalence of veterinary NSAIDs. The purpose was to establish whether sales of diclofenac had continued and to determine which other veterinary NSAIDs were available. In India, the availability of diclofenac had declined in all Vulture Safe Zones (VSZs), but it was still readily available (up to 25% of sales) in Rajasthan where intensive conservation advocacy had not occurred. Elsewhere in the region, prevalence of diclofenac was low. The vulture-safe meloxicam continued to be the most commonly available veterinary NSAID throughout most of the region, especially in Nepal (85–100%), but still accounted for only 25–45% of products offered in other countries. In Bangladesh, the vulture-toxic ketoprofen was the most prevalent drug overall, but levels declined to a low level (<1% in 2024), following the nationwide ban on veterinary use of the drug in 2023. Fourteen different NSAIDs were recorded in our surveys, several of which are known or suspected to be toxic to vultures. Of special concern is a rapid increase in the prevalence of flunixin in Bangladesh. Flunixin has not been banned in any of the South Asian vulture range states. Conservation priorities should include awareness campaigns, stronger measures to implement current bans, safety-testing of other NSAIDs, especially flunixin, followed by bans on veterinary use of all NSAIDs found to be toxic to vultures. Prior evidence of safety to vultures should be a requirement for the licensing of all new veterinary NSAIDs
Rainwater harvesting for Managed Aquifer Recharge (MAR)—a case study from urban centre in Punjab Pakistan
Get PDFRising trends in global population have resulted in increased urbanization, industrialization, and food demands. This has resulted in the rapidly increasing water demands for domestic, agricultural and industrial sectors; which have severely depleted groundwater resources in Pakistan. The urban centres like Lahore city—the capital of Punjab province and the 2nd largest city of Pakistan. To address this challenge, a field-scale Managed Aquifer Recharge (MAR) system integrated with Rainwater Harvesting (RWH) was developed and tested to evaluate its feasibility and efficiency for urban groundwater recovery. In this system, rainwater collected from paved surfaces was filtered and injected into a Pleistocene sand aquifer through recharge wells. Double filtration mechanism has been introduced in the model to ensure good quality rainwater is recharged into the aquifer. Field monitoring during multiple rainfall events demonstrated successful infiltration and aquifer-storage, with recharge volumes of 150,700, 281,097, and 89,887 L of rainwater corresponding to potential domestic water supplies for 132, 246, and 79 days for an average household respectively. The results confirm that decentralized RWH–MAR systems can significantly enhance aquifer replenishment in overexploited urban aquifers. The study underscores the viability of such systems for broader implementation in Punjab and other similar semi-arid regions, contributing to sustainable groundwater management and urban water resilience in Pakistan
Engineering of a novel amphibian skin peptide isolated from Agua Rica Leaf Frog (Callimedusa ecuatoriana) into active antimicrobial agents
Get PDFBackground/Objectives: The increasing antimicrobial resistance is a current human health threat, which has stimulated research on new biologically active molecules against infections caused by microorganisms resistant to conventional therapies. Antimicrobial peptides (AMPs) from amphibian skin secretions have generated great interest in tackling this problem due to their antibacterial, antifungal, antiprotozoal, wound-healing, and even anticancer properties. In Ecuador, there are still unexplored endemic amphibian species as a source of new AMPs, such as Callimedusa ecuatoriana. In this study, we report a novel peptide derived from the skin secretion of Callimedusa ecuatoriana identified by molecular cloning of the mRNA precursor. The functional analysis demonstrated that it lacks antimicrobial activity due to its alpha-helix kink structure. Methods: Inspired by the native structure of PTR-CE1, we designed and synthesized two analogs (PTR-CE1a and PTR-CE1b) to adopt a complete α-helix secondary structure, a conformation often associated with antimicrobial activity. In silico tools were used to predict the peptide activity, which was confirmed by experimental findings. Results: Both analogs displayed higher activity than the native peptide, even against the ampicillin-resistant bacterial strain. While PTR-CE1b showed Minimum Inhibitory Concentration (MIC) values of 26.62–212.99 μM and 24.36% of hemolytic activity at 26.62 μM, PTR-CE1a displayed a more potent broad-spectrum activity against all the microorganisms, with MIC values of 3.02–12.06 μM and hemolytic activity of 7.5% at 3.02 μM. Conclusions: This study demonstrates the importance of the α-helix structure for antimicrobial activity in C. ecuatoriana PTR-CE1 analogs and highlights the potential of unexplored biological and molecular diversity in endemic species of Ecuador to provide novel templates for peptide design
