Topic familiarity and story continuation in young English as a foreign language learners’ writing tasks

Prior research demonstrates that primary and secondary school teachers often find teaching young learners to write in a second language a slow and effortful process. Moreover, students in this age range lack the motivation to write. Therefore, it is important to explore the EFL writing pedagogy suitable for young learners. The present study investigated how story continuation (with or without reading input) under different topic familiarity conditions serves as a viable pedagogical means for secondary school students. Ninety-one Chinese students in four intact classes of comparable proficiency levels were assigned four writing task conditions in a 2 ⨉ 2 factorial design. Group 1 (Fam) was provided with the beginning of a familiar story in L1 Chinese and was required to complete the story in L2 English. Group 2 (UnFam) had the same task as Group 1, with an unfamiliar story. Group 3 (Fam+Input) was initially provided with the complete familiar story in Chinese (the same story as Group 1) as reading input and were then instructed to write the story in English with the reading material taken away. Group 4 (Unfam+Input) received the full unfamiliar story in Chinese (the same story as Group 2) as input before writing. Again they were not allowed to refer to the reading in the composing process. The results revealed that the young learners who wrote on familiar topics (Groups 1 and 3) produced longer texts and demonstrated greater lexical diversity than those with unfamiliar stories (Groups 2 and 4), although topic familiarity did not affect their writing quality or lexical sophistication. As for the story continuation conditions, students who completed writing the story without the L1 reading input on the topics (Groups 1 and 2) developed longer compositions and better writing quality than those with such input (Groups 3 and 4), although their lexical profiles (both lexical diversity and lexical sophistication) remained uninfluenced. Pedagogical implications for EFL writing among young learners were also discussed in the present study

Overexpression of Nitrate Transporter <i>OsNRT2.1</i> Enhances Nitrate-Dependent Root Elongation

Root morphology is essential for plant survival. NO3&#8722; is not only a nutrient, but also a signal substance affecting root growth in plants. However, the mechanism of NO3&#8722;-mediated root growth in rice remains unclear. In this study, we investigated the effect of OsNRT2.1 on root elongation and nitrate signaling-mediated auxin transport using OsNRT2.1 overexpression lines. We observed that the overexpression of OsNRT2.1 increased the total root length in rice, including the seminal root length, total adventitious root length, and total lateral root length in seminal roots and adventitious roots under 0.5-mM NO3&#8722; conditions, but not under 0.5-mM NH4+ conditions. Compared with wild type (WT), the 15NO3&#8722; influx rate of OsNRT2.1 transgenic lines increased by 24.3%, and the expressions of auxin transporter genes (OsPIN1a/b/c and OsPIN2) also increased significantly under 0.5-mM NO3&#8722; conditions. There were no significant differences in root length, &#223;-glucuronidase (GUS) activity, and the expressions of OsPIN1a/b/c and OsPIN2 in the pDR5::GUS transgenic line between 0.5-mM NO3&#8722; and 0.5-mM NH4+ treatments together with N-1-naphthylphalamic acid (NPA) treatment. When exogenous NPA was added to 0.5-mM NO3&#8722; nutrient solution, there were no significant differences in the total root length and expressions of OsPIN1a/b/c and OsPIN2 between transgenic plants and WT, although the 15NO3&#8722; influx rate of OsNRT2.1 transgenic lines increased by 25.2%. These results indicated that OsNRT2.1 is involved in the pathway of nitrate-dependent root elongation by regulating auxin transport to roots; i.e., overexpressing OsNRT2.1 promotes an effect on root growth upon NO3&#8722; treatment that requires active polar auxin transport

Origin of brines and modern water circulation contribution to Qarhan salt lake in Qaidam basin, Tibetan plateau

Lake Qarhan is the largest salt lake and potassium salt resource mining base in china. Understanding the origin of brines and the contribution of modern water circulation is extremely important to the sustainable development of the salt lake. Comprehensive tools including isotope, hydrochemistry and numerical simulation had been performed. Results suggest that brine groundwater in the salt lake area is the result of ancient brines migrated from the western Qaidam Basin due to the uplift of the western basin in the geological past. Shallow phreatic aquifers in the salt lake area are also recharged by the modern surface water in the flood period. The contribution of modern groundwater circulation to the salt lake area is very limited with only 3% of the total quantity of groundwater discharge for the watershed

Essential role of Dhx16-mediated ribosome assembly in maintenance of hematopoietic stem cells

Hematopoietic stem cells (HSCs) are vital for the differentiation of all mature blood cells, with their homeostasis being tightly regulated by intrinsic and extrinsic factors. Alternative splicing, mediated by the spliceosome complex, plays a crucial role in regulating HSC homeostasis by increasing protein diversity. This study focuses on the ATP-dependent RNA helicase DHX16, a key spliceosome component, and its role in HSC regulation. Using conditional knockout mice, we demonstrate that loss of Dhx16 in the hematopoietic system results in significant depletion of hematopoietic stem and progenitor cells, bone marrow failure, and rapid mortality. Dhx16-deficient HSCs exhibit impaired quiescence, G2-M phase cell cycle arrest, reduced protein synthesis, abnormal ribosome assembly, increased apoptosis, and decreased self-renewal capacity. Multi-omics analysis identified intron 4 retention in Emg1 mRNA in Dhx16 knockout HSCs, leading to reduced EMG1 protein expression, disrupted ribosome assembly, and nucleolar stress, activating the p53 pathway. Overexpression of Emg1 in Dhx16-deficient HSCs partially restored ribosome assembly and HSC function, suggesting Emg1 as a potential therapeutic target for ribosomopathies. Our findings reveal the critical role of Dhx16 in HSC homeostasis through the regulation of alternative splicing and ribosome assembly, providing insights into the molecular mechanisms underlying hematopoietic diseases and potential therapeutic strategies.</p