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In this study, we analyzed the imprecise (i.e., less mathematically precise) responses that 148 third- to fifth-grade Chinese students made on selected-response problems that were part of a spontaneous mathematical focusing task, the Quantitative Relations Test for Chinese Children (QRTC[superscript 2]). The purpose for this analysis was to ascertain whether the students' spontaneous responses represented random selections or followed discernible patterns. Those patterns were based on the specific attributes (i.e., featural, mathematical, numerical, and multiplicative) of the imprecise-response options for selected-response items on the QRTC[superscript 2]. Nonrandom selection patterns were identified by means of chi-square analysis and compared to patterns for the constructed-response portion of the QRTC[superscript 2]. For the chi-square analysis, the category involving imprecisions in both numerical and multiplicative attributes, and the category simultaneously involving numerical, multiplicative, and mathematical were significant. The analysis for the constructed problems also showed that children had difficulty describing the changes in the numerical and multiplicative attributes. Overall, the task of fully and accurately writing what they observed in the constructed-response problem on the QRTC[superscript 2] proved challenging for the children. Finally, imprecise response patterns the children exhibited on the QRTC[superscript 2] and their relational reasoning ability, as measured by the Test of Relational Reasoning-Junior (TORRjr) were significantly correlated. That significant correlation was attributable largely to the association between the children's analogical reasoning abilities and their QRTC[superscript 2] performance. We consider the theoretical, empirical, and practical implications of this work for mathematical learning and development.

Elemental tellurium electrical switch, relying on a transient crystal–liquid–crystal phase transition, has recently been proposed as a promising selector candidate for the next‐generation 3D high‐density memory, bridging performance gap in today's computer. Further miniaturization of the switch cell to increase memory density strongly depends on the scalability of the tellurium film, which, however, has not been experimentally studied. Herein, the tellurium films are prepared with the thickness downscaled from 400 to 2 nm and a significant increase is found in the bandgap from 0.29 to 0.91 eV, as predicted by ab initio molecular dynamics. Interestingly, the as‐deposited tellurium films with a thickness above 3 nm are in the crystalline trigonal phase, whereas 2 nm thick film suddenly becomes amorphous, observed by both Raman and transmission electron microscopies. In this finding, since the leakage current of the elemental tellurium switch is determined by both the Schottky barrier between tellurium/electrode interface and the bandgap of the tellurium film, a reduction in leakage current is predicted with further miniaturization. [ABSTRACT FROM AUTHOR]

BACKGROUND: The global prevalence of iron deficiency has posed significant public health risks. Animal‐derived collagen peptides have been recognized for their potent metal ion‐chelating capabilities, which can greatly enhance the bioavailability of iron. Yak skins, typically discarded during production and processing, serve as a valuable resource. Based on yak skin collagen peptide (YSP), we have developed a novel iron‐chelating peptide: yak skin collagen iron‐chelating peptide (YSP‐Fe). RESULTS: The maximum level of iron chelation of YSP‐Fe achieved was 42.72 ± 0.65 mg g−1. Structural analysis indicated that YSP‐Fe was primarily formed from amino, carboxyl and carbonyl groups combined with ferrous ions. Through examination of the amino acid composition, molecular docking and peptide sequence identification, it was determined that Gly, Asp and Arg played crucial roles in the chelation of ferrous ions by YSP. Furthermore, YSP‐Fe was more stable in simulated gastrointestinal digestion compared to FeSO4. CONCLUSION: YSP‐Fe demonstrated dual benefits of iron supplementation and antioxidant effects. These significant findings provide a foundation for the development of novel iron supplements and the effective utilization of yak skin as a valuable resource. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Metal halide materials have recently drawn increasing research interest for their excellent opto‐electronic properties and structural diversity, but their resulting rigid structures render them brittle and poor formability during manufacturing. Here we demonstrate a thermoplastic luminant hybrid lead halide solid by integrating lead bromide complex into tri‐n‐octylphosphine oxide (TOPO) matrix. The construction of the hybrid materials can be achieved by a simple dissolution process, in which TOPO molecules act as the solvents and ligands to yield the monodispersed clusters. The combination of these functional units enables the near‐room‐temperature melt‐processing of the materials into targeted geometry by simple molding or printing techniques, which offer possibilities for fluorescent writing inks with outstanding self‐healing capacity to physical damage. The intermarriage between metal halide clusters with functional molecules expands the range of practical applications for hybrid metal halide materials. [ABSTRACT FROM AUTHOR]

Elemental tellurium, a prototypical one‐dimensional van der Waals material, has recently been found to crystallize quickly from the liquid on a nanosecond timescale, yet the inherent mechanism is not clear. Here, by combining in situ high‐energy synchrotron radiation X‐ray diffraction with ab initio molecular‐dynamics simulation, it is found that trigonal crystalline Te completely melts into the liquid phase at 450 °C, and recrystallizes into the trigonal phase for temperatures lower than 380 °C without the formation of any other phase. This directly confirms the recent proposal of a crystal‐liquid‐crystal phase transition in this material underlying the observed electrical‐switching process. Atomic‐scale, melt‐quench computer simulations show that liquid Te is capable of crystallizing within a time of 25 ps in the vicinity of templating crystallization interfaces. This ultrafast crystallization ability of Te can be understood as being due to delayed Peierls distortions during a quench and therefore a high atomic mobility over a wide range of temperature. This finding opens the way to develop a crystal‐liquid‐crystal, phase‐transition‐based selector switch with an ultrafast switching speed. [ABSTRACT FROM AUTHOR]

Species distribution and activity patterns vary across regions, and these patterns reveal key information about the biology of a given species. However, such data in Niubeiliang National Nature Reserve located in the Qinling Mountains, Shaanxi Province, China, are inadequate due to limited monitoring studies. From September 2017 to December 2019, 57 infrared cameras were installed to monitor species distribution relative to distance from National Highway 210, and spatial and temporal activity patterns in Niubeiliang National Nature Reserve (elevation range 1,100 to 2,802 m). Sixteen species of mammals were recorded in our survey. The 4 most frequently detected species were Reeves's Muntjac (Muntiacus reevesi), Wild Boar (Sus scrofa), Pere David's Rock Squirrel (Sciurotamias davidianus), and Golden Takin (Budorcas taxicolor bedfordi). Daily patterns of these species indicated that Reeves's muntjacs and golden takins were more active at dawn and dusk, whereas wild boars and Pere David's rock squirrels were more active during the day. The relative abundance index of these mammals varied seasonally. Wild boars and Pere David's rock squirrels showed no obvious preference in elevation distribution, Reeves's muntjacs preferred low-elevation habitats (1,300 to 1,600 m), and golden takins mainly inhabited high-elevation areas (1,900 to 2,100 m). Golden takins showed obvious avoidance of roads, with avoidance distance from the road of >300 m. In contrast, Reeves's muntjacs were remarkably abundant within 200 m of the road. For both wild boars and Pere David's rock squirrels, there was no significant difference in RAI among 5 highway ranges. These findings help describe the distribution and activity patterns of these species in Qinling, to monitor their population dynamics, and to develop tailored conservation strategies for the 4 species and sympatric wildlife. [ABSTRACT FROM AUTHOR]

In China's rural land system, the collective owns the land, and farmers, as members of the collective, can acquire land contractual management rights through land contracting. With the second round of land contracts nearing expiration, the central government has announced that the term should be extended for 30 years. This paper introduces the theory of psychological ownership to explore the implementation paths of the 30-year extension policy. The study finds that (1) farmers generally exhibit strong psychological ownership towards the contracted land. (2) The Household Contract Responsibility System satisfies the three routes for the formation of psychological ownership—control, intimate knowledge, and self-investment. As the duration of farmers' possession of contracted land extends, their psychological ownership gradually forms and strengthens. (3) Farmers' psychological ownership has both positive and negative effects. The 30-year extension policy must adhere to the path dependence formed by the evolution of the land contract system, comply with the institutional constraints imposed by rural land collective ownership, and simultaneously meet the practical demands posed by urban–rural integration and agricultural development. Drawing on the complex effects of farmers' psychological ownership and considering the historical, institutional, and practical contexts of policy implementation, this study proposes the dual necessity of facilitating and restraining farmers' psychological ownership when extending for another 30 years and offers corresponding policy suggestions. Facilitation requires empowering farmers with more stable land possession and stronger land rights. Restraint requires preventing the permanent locking of rural land allocation patterns to achieve fair and efficient land allocation. [ABSTRACT FROM AUTHOR]

The aberrant expression of microRNAs (miRNAs) is involved in the initiation and progression of human cancers. In our study, we found that miR-539 was down-regulated in breast cancer tissues and cell lines. Decreased expression of miR-539 was significantly associated with lymph node metastasis in patients with breast cancer. Overexpression of miR-539 inhibited the proliferation and promoted apoptosis of breast cancer cells. Moreover, highly expressed miR-539 significantly suppressed the epithelial-mesenchymal transition (EMT) and sensitized cells to cisplatin treatment. Mechanistically, miR-539 was found to target the specificity protein 1 (SP1) and down-regulated the expression of SP1 in breast cancer cells. Knockdown of miR-539 consistently increased the expression of SP1. The expression of miR-539 in breast cancer tissues was negatively correlated with the expression of SP1. Restoration of SP1 significantly attenuated the inhibitory effect of miR-539 on the proliferation of breast cancer cells. Taken together, our results indicate that miR-539 has a tumor suppressive role in breast cancer via targeting SP1, suggesting miR-539 as a promising target for the diagnosis of breast cancer. Key words: miR-539, breast cancer, SP1. L'expression anormale des microARN (miARN) a ete impliquee dans l'initiation et la progression des cancers chez l'humain. Les auteurs ont trouve ici que le miR-539 etait regule a la baisse dans les tissus et les lignees de cancer du sein. L'expression reduite du miR-539 etait significativement associee aux metastases ganglionnaires chez les personnes atteintes du cancer du sein. La surexpression du miR-539 inhibait la proliferation et favorisait l'apoptose des cellules de cancer du sein. De plus, le miR-539 fortement exprime reprimait significativement la transition epithelio-mesenchymateuse (TEM) et sensibilisait les cellules au traitement au cisplatine. D'un point de vue du mecanisme, le miR-539 s'est avere cibler la proteine SP1 (specificity protein 1) et reguler a la baisse l'expression de SP1 dans les cellules de cancer du sein. De la meme maniere, le knockdown du miR-539 augmentait l'expression de SP1. L'expression du miR-539 etait negativement correlee avec celle de SP1 dans les tissus de cancer du sein. Le retablissement de SP1 attenuait significativement l'effet inhibiteur du miR-539 sur la proliferation des cellules de cancer du sein. L'ensemble de ces resultats indiquait que le miR-539 exerce un role de suppresseur tumoral dans le cancer du sein en ciblant SP1, suggerant le miR-539 comme cible prometteuse dans le diagnostic du cancer du sein. [Traduit par la Redaction] Mots-cles : miR-539, cancer du sein, SP1., Introduction Breast cancer is the most common malignancy with high mortality among women worldwide (Fan et al. 2014; Kotsopoulos 2018). The conventional therapeutic approaches for breast cancer include surgical resection, [...]

The assessment of quality in higher education from the perspective of students has three dimensions: students' assessment of teaching, students' satisfaction and students' learning engagement. These differ in conceptions of quality, evaluation methods, evaluation content, evaluation purposes, traits and priorities. The authors conducted three rounds of empirical investigations to study higher education quality assessment from students' perspective and concluded that students play multiple roles in higher education evaluation and assessment, all of which can be improved by strengthening students' objectivity and participation, evaluating the added value of a college education oriented to student development and taking the students' perspective as an important way to contribute to higher education quality enhancement, assurance and control, and make proper use of higher education evaluations and assessments.