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Background: Coding has become an integral part of STEM education. However, novice learners face difficulties in processing codes within embedded structures (also termed nested structures). This study aimed to investigate the cognitive mechanism underlying the processing of embedded coding structures based on hierarchical complexity theory, which suggests that more complex hierarchies are involved in embedded versus sequential coding structures. Hierarchical processing is expected to place a great load on the working memory system to maintain, update, and manipulate information. We therefore examined the difference in cognitive load induced by embedded versus sequential structures, and the relations between the difference in cognitive load and working memory capacity. Results: The results of Experiment 1 did not fully support our hypotheses, possibly due to the unexpected use of cognitive strategies and the way stimuli were presented. With these factors well controlled, a new paradigm was designed in Experiment 2. Results indicate that the cognitive load, as measured by the accuracy and response times of a code comprehension task, was greater in embedded versus sequential conditions. Additionally, the extra cognitive load induced by embedded coding structures was significantly related to working memory capacity. Conclusions: The findings of these analyses suggest that processing embedded coding structures exerts great demands on the working memory system to maintain and manipulate hierarchical information. It is therefore important to provide scaffolding strategies to help novice learners process codes across different hierarchical levels within embedded coding structures.

Low‐dose 5‐aminolevulinic acid photodynamic therapy (ALA‐PDT) has been used to cope with skin photoaging, and is thought to involve DNA damage repair responses. However, it is still unknown how low‐dose ALA‐PDT regulates DNA damage repair to curb skin photoaging. We established a photoaging model using human dermal fibroblasts (HDFs) and rat skin. RNA‐sequencing (RNA‐seq) analysis was conducted to identify differentially expressed genes (DEGs) in HDFs before and after low‐dose ALA‐PDT treatment, followed by bioinformatics analysis. Senescence‐associated β‐galactosidase (SA‐β‐gal) staining was employed to assess skin aging‐related manifestations and Western blotting to evaluate the expression of associated proteins. A comet assay was used to detect cellular DNA damage, while immunofluorescence to examine the expression of 8‐hydroxy‐2′‐deoxyguanosine (8‐oxo‐dG) in cells and skin tissues. In both in vivo and in vitro models, low‐dose ALA‐PDT alleviated the manifestations of ultraviolet B (UVB)‐induced skin photoaging. Low‐dose ALA‐PDT significantly reduced DNA damage in photoaged HDFs. Furthermore, low‐dose ALA‐PDT accelerated the clearance of the photoproduct 8‐oxo‐dG in photoaged HDFs and superficial dermis of photoaged rat skin. RNA‐seq analysis suggested that low‐dose ALA‐PDT upregulated the expression of key genes in the base excision repair (BER) pathway. Further functional validation showed that inhibition on BER expression by using UPF1069 significantly suppressed SA‐β‐gal activity, G2/M phase ratio, expression of aging‐associated proteins P16, P21, P53, and MUTYH proteins, as well as clearance of the photoproduct 8‐oxo‐dG in photoaged HDFs. Low‐dose ALA‐PDT exerts anti‐photoaging effects by activating the BER signalling pathway. [ABSTRACT FROM AUTHOR]

Designing the markets that allocate public school seats is a crucial policy consideration. This paper compares the design of school choice mechanisms in terms of economic efficiency, stability, and strategic behavior. We estimate demand for schools using data from a large US public school system with novel indicators of students' levels of strategic sophistication. We find important benefits of reserving a set of seats to be assigned by a pure lottery. In settings that share features in common with the school system we study, our findings suggest that non‐selective criteria such as lotteries induce a large increase in truth‐telling. [ABSTRACT FROM AUTHOR]

Coherence scanning interferometry (CSI) is a widely used non-contact method for measuring areal surface topography. The calculation of groove depth typically employs the 'W/3 rule' specified in ISO 5436-1. However, the batwing effect causes overshoots near the groove edges, which can introduce noise singularities in the selected W/3 region for depth calculation, thereby affecting the measurement of rectangular grating depth. This paper introduces the definition of batwing height and width and proposes a simulation model that considers various factors, such as the center wavelength, spectrum of the illuminating light, shadow effect, and numerical aperture, to analyze their influence on depth measurement. The simulation results demonstrate that the batwing width is the primary factor influencing depth measurement for small grating periods. Specifically, a decrease in numerical aperture increases the batwing width, leading to larger depth measurement errors, while a decrease in the center wavelength reduces the batwing width, resulting in smaller depth measurement errors. The influence of the illumination spectrum and shadow effect on depth measurement is found to be minor. Experimental validation using a step standard consisting of rectangular gratings with different periods and depths confirms the agreement between the experimental and simulated results. The proposed method provides a quantitative evaluation of depth measurement accuracy in CSI. [ABSTRACT FROM AUTHOR]

Livelihood capital is an important basis for farmers to carry out different livelihood activities. In order to consolidate the achievements of poverty alleviation, it is necessary to clarify the specific impact of the livelihood capital of poverty alleviation households on their livelihood strategies. Based on the livelihood capital assessment of poverty alleviation households, this paper analyzes the impact of poverty alleviation households’ livelihood capital on livelihood strategies from two aspects: dominant livelihood strategies and diversified livelihood strategies. The study found that financial capital was significantly positively correlated with the dominant strategy of agricultural management, human capital and social capital were significantly positively correlated with the dominant strategy of migrant labor, and physical capital and natural capital were significantly positively correlated with the dominant strategy of transfer payments; the richer the livelihood capital, the more diverse the livelihood strategies of the poverty alleviation households, the human capital and social capital have an important impact on the diversity of the livelihood strategies of the poverty alleviation households.

Targeted immunotherapies capitalize on the exceptional binding capabilities of antibodies to stimulate a host response that effectuates long‐lived tumor destruction. One example is the conjugation of immunoglobulins (IgGs) to immune effector cells, which equips the cells with the ability to recognize and accurately kill malignant cells through a process called antibody‐dependent cellular cytotoxicity (ADCC). In this study, a chemoenzymatic reaction is developed that specifically functionalizes a single tyrosine (Tyr, Y) residue, Y296, in the Fc domain of therapeutic IgGs. A one‐pot reaction that combines the tyrosinase‐catalyzed oxidation of tyrosine to o‐quinone with a subsequent [3+2] photoaddition with vinyl ether is employed. This reaction installs fluorescent molecules or bioorthogonal groups at Y296 of IgGs or the C‐terminal Y‐tag of an engineered nanobody. The Tyr‐specific reaction is utilized in constructing monofunctionalized antibody‐drug conjugates (ADCs) and antibody/nanobody‐conjugated effector cells, such as natural killer cells or macrophages. These results demonstrate the potential of site‐selective antibody reactions for enhancing targeted cancer immunotherapy. [ABSTRACT FROM AUTHOR]