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This paper conducts an analysis of the site selection methods for power grid material distribution centers. It proposes the fundamental principles for site selection and organizes and compares representative models and commonly used methods in site selection issues. Taking the establishment and solving process of the site selection model for power grid material distribution centers as an example, the specific methods and procedures of Sparrow Search Algorithm applied to site selection problems are explained, and analyzes the shortcomings of this method. Finally, building upon the comparison and summary of simulated annealing algorithm and Sparrow Search Algorithm in the preceding sections, this paper combines their strengths to propose an approach for optimizing the solution method that is, using the former to update the iterative optimal solution of the latter, in order to reduce the risk of falling into local optimization, enhance the accuracy of problem-solving, and improve distribution efficiency. This contributes as a reference for similar site planning and decision-making processes.

Longitudinal optical field modulation is of critical importance in a wide range of applications, including optical imaging, spectroscopy, and optical manipulation. However, it remains a considerable challenge to realize a uniformly distributed light field with extended depth-of-focus. Here, a high-efficiency extended depth-of-focus metalens is proposed by adjoint-based topology-shape optimization approach, wherein the theoretical electric field intensity corresponding to a variable focal-length phase is utilized as the figure of merit. Using a dozen of metalens with random structure parameters as initial structures, the average focal depth of topology-shape optimized metalens is greatly improved up to 18.80 μm (about 29.7λ), which is 1.54 times higher than the diffraction-limited focal depth. Moreover, all the topology-shape optimized metalens exhibit high diffraction efficiency exceeding 0.7 over the whole focal depth range, which is approximately three times greater than that of the forward design. Our results offer a new insight into the design of extended depth-of-focus metalens and may find potential applications in imaging, holography, and optical fabrication.

Recently, full Poincaré beams (FPBs) with spatially variant polarization states spanning the entire surface of the Poincaré sphere have attracted considerable interests. Expanding the FPBs into an array way has the promising applications from multiparticle manipulation to optical communication. However, how to efficiently generate a high‐purity FPB array with intracavity method remains elusive. Here, a metasurface‐integrated degenerate cavity laser is proposed for efficient generation of 10 × 10 FPB array, where a pair of metasurfaces are adopted to independently modulate the circular polarization state while compensating the mode discrepancies within the cavity. Such a design strategy enables a self‐reproducing intracavity optical field, concurrently ensuring the stabilization of intracavity oscillation. It is numerically demonstrated that the purity of orbital angular momentum (OAM) in the first‐order FPB array can approach to 92.89%, with a root‐mean‐square error (RMSE) of polarization ellipse parameters below 8.17%. This work provides a compact and efficient design platform for the generation of a variety of vector beam arrays and may find promising applications in free space communication and multiple particle manipulation. [ABSTRACT FROM AUTHOR]

Despite exhibiting potent anticancer activity, the strong hemolytic properties of melittin (MEL) significantly restrict its delivery efficiency and clinical applications. To address this issue, we have devised a strategy wherein homologous dopamine (DA), an essential component of bee venom, is harnessed as a vehicle for the synthesis of MEL–polydopamine (PDA) nanoparticles (MP NPs). The ingenious approach lies in the fact that MEL is a basic polypeptide, and the polymerization of DA is also conducted under alkaline conditions, indicating the distinctive advantages of PDA in MEL encapsulation. Furthermore, MP NPs are modified with folic acid to fabricate tumor-targeted nanomedicine (MPF NPs). MPF NPs can ameliorate the hemolysis of MEL in drug delivery and undergo degradation triggered by high levels of reactive oxygen species (ROS) within solid tumors, thereby facilitating MEL release and subsequent restoration of anticancer activity. After cellular uptake, MPF NPs induce cell apoptosis through the PI3K/Akt-mediated p53 signaling pathway. The tumor growth inhibitory rate of MPF NPs in FA receptor-positive 4T1 and CT26 xenograft mice reached 78.04% and 81.66%, which was significantly higher compared to that in FA receptor-negative HepG2 xenograft mice (45.79%). Homologous vehicles provide a new perspective for nanomedicine design. [ABSTRACT FROM AUTHOR]

Global macroeconomic development is faced with great uncertainty, especially the repeated impact of COVID-19, which exacerbate the challenges. This study explores the impact of Internet development on the resilience of cities. In the first place, a theoretical model is used to analyse how Internet development affects productivity and further influences urban economic resilience. Based on this, a long-differences model is established for empirical analysis. The study found that improving Internet development is an important step enhancing urban economic resilience. The results provide new perspectives and evidence for the study of urban economic resilience. [ABSTRACT FROM AUTHOR]

Summary: Plant leaf senescence, caused by multiple internal and environmental factors, has an important impact on agricultural production. The lectin receptor‐like kinase (LecRLK) family members participate in plant development and responses to biotic and abiotic stresses, but their roles in regulating leaf senescence remain elusive. Here, we identify and characterize a rice premature withered leaf 1 (pwl1) mutant, which exhibits premature leaf senescence throughout the plant life cycle. The pwl1 mutant displayed withered and whitish leaf tips, decreased chlorophyll content, and accelerated chloroplast degradation. Map‐based cloning revealed an amino acid substitution (Gly412Arg) in LOC_Os03g62180 (PWL1) was responsible for the phenotypes of pwl1. The expression of PWL1 was detected in all tissues, but predominantly in tillering and mature leaves. PWL1 encodes a G‐type LecRLK with active kinase and autophosphorylation activities. PWL1 is localized to the plasma membrane and can self‐associate, mainly mediated by the plasminogen‐apple‐nematode (PAN) domain. Substitution of the PAN domain significantly diminished the self‐interaction of PWL1. Moreover, the pwl1 mutant showed enhanced reactive oxygen species (ROS) accumulation, cell death, and severe DNA fragmentation. RNA sequencing analysis revealed that PWL1 was involved in the regulation of multiple biological processes, like carbon metabolism, ribosome, and peroxisome pathways. Meanwhile, interfering of biological processes induced by the PWL1 mutation also enhanced heat sensitivity and resistance to bacterial blight and bacterial leaf streak with excessive accumulation of ROS and impaired chloroplast development in rice. Natural variation analysis indicated more variations in indica varieties, and the vast majority of japonica varieties harbour the PWL1Hap1 allele. Together, our results suggest that PWL1, a member of LecRLKs, exerts multiple roles in regulating plant growth and development, heat‐tolerance, and resistance to bacterial pathogens. [ABSTRACT FROM AUTHOR]

N6‐methyladenosine (m6A) modification has been implicated in the progression of obesity and metabolic diseases. However, its impact on beige fat biology is not well understood. Here, via m6A‐sequencing and RNA‐sequencing, this work reports that upon beige adipocytes activation, glycolytic genes undergo major events of m6A modification and transcriptional activation. Genetic ablation of m6A writer Mettl3 in fat tissues reveals that Mettl3 deficiency in mature beige adipocytes leads to suppressed glycolytic capability and thermogenesis, as well as reduced preadipocytes proliferation via glycolytic product lactate. In addition, specific modulation of Mettl3 in beige fat via AAV delivery demonstrates consistently Mettl3's role in glucose metabolism, thermogenesis, and beige fat hyperplasia. Mechanistically, Mettl3 and m6A reader Igf2bp2 control mRNA stability of key glycolytic genes in beige adipocytes. Overall, these findings highlight the significance of m6A on fat biology and systemic energy homeostasis. [ABSTRACT FROM AUTHOR]

The availability of spectral library makes hyperspectral sparse unmixing an attractive unmixing scheme, and the powerful feature extraction capability of deep learning meets the requirements of estimating abundances with hundreds of channels in sparse unmixing. However, few related researches have been carried out. In this letter, we propose a window transformer convolutional autoencoder (WiTCAE) to address the sparse unmixing problem. In our method, a well-designed transformer encoder for hyperspectral images (HIS) is applied before convolutional neural network (CNN), aiming at exploring nonlocal information by a new attention mechanism called window-based pixel-level multihead self-attention (WP-MSA). Three consecutive CNN blocks focus on further joint spatial–spectral feature extraction and adjust the number of channels to the number of endmembers contained in the spectral library. Moreover, CNN establishes the connections among windows and smooths out the discontinuities caused by window partition. The decoder is a convolutional layer with a kernel size of 1, and its weights are fixed to a known spectral library. Comparative experiments on both simulated and real datasets confirm the superiority of our proposed network. [ABSTRACT FROM AUTHOR]

In this study, headspace solid‐phase microextraction (HS‐SPME) combined with gas chromatography‐time‐of‐flight mass spectrometry (GC‐TOFMS) was used to detect and analyse the volatile components of five samples with different degrees of fragmentation, combined with cluster analysis, orthogonal partial least squares discrimination analysis (OPLS‐DA) and relative odour activity value (ROAV) analysis. The results showed that 70 volatile components were detected and identified in samples with different degrees of fragmentation. 40 were co‐containing components. Cluster analysis revealed a high degree of similarity between samples B (20 mesh sieve top) and C (40 mesh sieve top), which were grouped into one category. The order of variation in the relative content of volatile components was A (unbroken) > E (120 mesh sieve top) > D (80 mesh sieve top) > B. C; the OPLS‐DA analysis revealed significant differences in the volatile composition of rice samples with different degrees of fragmentation, This variation between samples is mainly due to the relative content of volatile components of 36 projections of variable importance (VIP > 1), such as ethyl butyrate, ethyl phenylacetate, and dimethyl trisulfide. A total of 12 volatile components with ROAV > 1, including ethyl hexanoate, 2‐acetyl‐1‐pyrroline, and E‐2‐nonenal, were found to be the key volatile components in five samples based on their ROAV, the different degrees of crushing had a greater impact on the overall aroma of the rice, and the results can be used as a reference for further rice processors. [ABSTRACT FROM AUTHOR]

Follicular dendritic cells (FDCs) are a specialized type of stromal cells that exclusively reside in B‐cell follicles. When inflammation occurs, the FDC network is reorganized to support germinal center (GC) polarization into the light zone (LZ) and dark zone (DZ). Despite the indispensable role of FDCs in supporting humoral responses, the FDC regulatory requirements remain incompletely defined. In this study, we unexpectedly observed an accumulation of CD169+ subcapsular sinus macrophage (SSM)‐derived microvesicles (MVs) in the B‐cell zone, which were tightly associated with the FDC network. Interestingly, a selective deposition of CD169+ MVs was detected in both GC LZ FDCs in secondary follicles and on predetermined LZ FDCs in primary follicles. The ablation of CD169+ MVs, resulting from SSM depletion, resulted in significantly decreased expression of LZ‐related genes in FDCs. In addition, we found that CD169+ MVs could colocalize with fluorescently tagged antigen‐containing immune complexes (ICs), supporting a possible role of CD169+ MVs in transporting antigens to the FDC network. Thus, our data reveal intimate crosstalk between FDCs and SSMs located outside B‐cell follicles via SSM‐released MVs, providing a novel perspective on the mechanisms underlying the regulation of FDC maturation and polarization. [ABSTRACT FROM AUTHOR]

Urban regeneration (UR) has been a leading concern in urban studies globally. China's rapid urbanization has undergone profound urban decay and social contestation, for which UR has emerged as a viable solution. However, UR is not without its drawbacks. It has caused emerging spatial and planning problems; however, few studies have explored the characteristics and issues of UR from the view of spatial analytics on the city scale. This study aims to depict the distribution characteristics of UR projects in Chinese cities and to reveal whether it meets the requirements of urban development from the planning perspective. The nearest neighbor index and its hierarchical clustering, as well as kernel density estimation are used in conjunction to investigate the spatial distribution characteristics; and the relationship between project distribution and each urban development indicator is explored using mixed spatial characteristics analyses, such as buffer analysis, space syntax, and heat mapping. Considering Shenzhen as the empirical study city, this research is based on all officially released data of implemented UR projects between 2010 and 2021. The findings imply that the UR projects in Shenzhen are mostly located in areas with higher economic development levels and accessibility with areas witnessing industrial restructuring and severe urban decay being prone to be designated for UR initiatives. The spatial distribution characteristics disclose the challenges inherent in the mix of top-down and market-driven UR approaches as well as the dilemma of the center-periphery pattern in UR implementation. Furthermore, the contradiction between the growing population and limited land resources as well as the barriers to industrial clustering formation are also revealed. This study enriches the methodological framework for spatial and visualization studies of urban regeneration in worldwide cities and sheds light on how to promote UR in regard to urban sustainability with ramifications for future urban development in other Chinese cities. [ABSTRACT FROM AUTHOR]

Polydopamine (PDA) has been applied widely in electronic elements, environmental management, and biomedical science. However, simple, mild, ultrathin, and template‐free 2D PDA (2D‐PDA) fabrication is still a big challenge. Herein, single‐layered 2D‐PDA is fabricated via an oxidation‐based exfoliation route by hydrogen peroxide (H2O2). The thickness of 2D‐PDA is 3.4 Å, similar to that of single‐layered graphene. Melanin‐like 2D‐PDA with a photothermal conversion rate (η) of 27.16% is a promising hyperthermia agent in cancer treatment (photothermal therapy, PTT). Furthermore, the plane‐oriented orientation 2D‐PDA with a high surface area is designed as a zinc phthalocyanine (ZnPc, a photosensitizer for photodynamic therapy, PDT) carrier to fabricate nanomedicine (denoted PZNSs). Upon the combined light irradiation, PZNSs achieve satisfactory synergistic anticancer efficiency. [ABSTRACT FROM AUTHOR]

Transmembrane kinases (TMKs) play important roles in plant growth and signaling cascades of phytohormones. However, its function in the regulation of early leaf senescence (ELS) of plants remains unknown. Here, we report the molecular cloning and functional characterization of the WATER-SOAKED SPOT1 gene which encodes a protein belongs to the TMK family and controls chloroplast development and leaf senescence in rice (Oryza sativa L.). The water-soaked spot1 (oswss1) mutant displays water-soaked spots which subsequently developed into necrotic symptoms at the tillering stage. Moreover, oswss1 exhibits slightly rolled leaves with irregular epidermal cells, decreased chlorophyll contents, and defective stomata and chloroplasts as compared with the wild type. Map-based cloning revealed that OsWSS1 encodes transmembrane kinase TMK1. Genetic complementary experiments verified that a Leu396Pro amino acid substitution, residing in the highly conserved region of leucine-rich repeat (LRR) domain, was responsible for the phenotypes of oswss1. OsWSS1 was constitutively expressed in all tissues and its encoded protein is localized to the plasma membrane. Mutation of OsWSS1 led to hyper-accumulation of reactive oxygen species (ROS), more severe DNA fragmentation, and cell death than that of the wild-type control. In addition, we found that the expression of senescence-associated genes (SAGs) was significantly higher, while the expression of genes associated with chloroplast development and photosynthesis was significantly downregulated in oswss1 as compared with the wild type. Taken together, our results demonstrated that OsWSS1, a member of TMKs, plays a vital role in the regulation of ROS homeostasis, chloroplast development, and leaf senescence in rice. [ABSTRACT FROM AUTHOR]

Remote sensing is the main approach to map aquatic vegetation, and classification tree (CT) is superior to various classification methods. Based on previous studies, modified CT can be developed from traditional CT by adjusting the thresholds based on the statistical relationship between spectral features to classify different images without ground-truth data. However, no studies have yet employed this method to resolve marine vegetation. In this study, three Gao-Fen 1 satellite images obtained on 30 January 2014, 5 November 2014 and 21 January 2015 were selected, and two features were then employed to extract macroalgae farms. Results show that the overall accuracies of traditional CTs for three images are 92.0, 94.2 and 93.9%, respectively, whereas those of the two corresponding modified CTs for images obtained on 21 January 2015 and 5 November 2014 are 93.1 and 89.5%, respectively. This indicates modified CTs can map macroalgae with multi-date imagery and monitor their spatiotemporal distribution in coastal environments. [ABSTRACT FROM AUTHOR]

The humic-like substances were the main organic components in most wastewater (e.g. domestic sewage, toilet wastewater and landfill leachate). Two types of actual humic-like substances (fulvic acid (FA) and biologically treated landfill leachate (BTLL)) were selected to describe the changes in the properties of humic-like substances (complexation ability, aromaticity and mobility) during electrochemical oxidation. Meanwhile, the acute cytotoxicity of FA and BTLL was also tested by acute toxicological test of luminescent bacteria. The results showed that the consumption of coordinating groups such as phenolic groups and hydrogen bonds reduced the complexation ability of FA and BTLL. The functional groups were degraded with the removal order of quinone group, phenolic group and aromatic group, and finally realized the molecular saturation and aromaticity decrease for humic-like substances. The mobility of FA and BTLL was decreased because of the enhancement of hydrophobicity during electrolysis process. Furthermore, the available chlorine produced during electrochemical oxidation was the main acute cytotoxicity substance, therefore, it is necessary to remove it before discharge in order to reduce ecological risks. This study provides a basis for understanding and evaluating the electrochemical degradation process of humic-like substances in detail. The changes of complexation ability, aromaticity, mobility and cytotoxicity of humic-like substances during electrochemical oxidation process. Image 1 • Complexation, aromaticity and mobility of humic-like were decreased by electrolysis. • Functional groups were degraded with the order of quinone, phenolic and aromatic. • The hydrophobicity of humic-like substances was enhanced during electrolysis. • The effluent acute cytotoxicity was decreased with the available chlorine removal. • Electrochemical oxidation was an approaching technology with low ecological risk. [ABSTRACT FROM AUTHOR]

Macroalgae plays an important role in coastal ecosystems. The accurate delineation of macroalgae areas is important for environmental management. This study compared the pixel- and object-based methods using Gaofen satellite no. 2 image to explore an efficient classification approach. Expert system rules and nearest neighbour classifier were adopted for object-based classification, whereas maximum likelihood classifier was implemented in the pixel-based approach. Normalized difference vegetation index, normalized difference water index, mean value of the blue band and geometric characteristics were selected as features to distinguish macroalgae farms by considering the spectral and spatial characteristics. Results show that the object-based method achieved a higher overall accuracy and kappa coefficient than the pixel-based method. Moreover, the object-based approach displayed superiority in identifying Porphyra class. These findings suggest that the object-based method can delineate macroalgae farming areas efficiently and be applied in the future to monitor the macroalgae farms with high spatial resolution imagery. [ABSTRACT FROM AUTHOR]