The architecture of silk-secreting organs during the final larval stage of silkworms revealed by single-nucleus and spatial transcriptomics.

Natural silks are renewable proteins with impressive mechanical properties and biocompatibility that are useful in various fields. However, the cellular and spatial organization of silk-secreting organs remains unclear. Here, we combined single-nucleus and spatially resolved transcriptomics to systematically map the cellular and spatial composition of the silk glands (SGs) of mulberry silkworms late in larval development. This approach allowed us to profile SG cell types and cell state dynamics and identify regulatory networks and cell-cell communication related to efficient silk protein synthesis; key markers were validated via transgenic approaches. Notably, we demonstrated the indispensable role of the ecdysone receptor (ultraspiracle) in regulating endoreplication in SG cells. Our atlas presents the results of spatiotemporal analysis of silk-secreting organ architecture late in larval development; this atlas provides a valuable reference for elucidating the mechanism of efficient silk protein synthesis and developing sustainable products made from natural silk.

Climate change impacts the distribution of Quercus section Cyclobalanopsis (Fagaceae), a keystone lineage in East Asian evergreen broadleaved forests.

East Asian evergreen broadleaved forests (EBFLs) harbor high species richness, but these ecosystems are severely impacted by global climate change and deforestation. Conserving and managing EBLFs requires understanding dominant tree distribution dynamics. In this study, we used 29 species in Quercus section Cyclobalanopsis-a keystone lineage in East Asian EBLFs-as proxies to predict EBLF distribution dynamics using species distribution models (SDMs). We examined climatic niche overlap, similarity, and equivalency among seven biogeographical regions' species using 'ecospat'. We also estimated the effectiveness of protected areas in the predicted range to elucidate priority conservation regions. Our results showed that the climatic niches of most geographical groups differ. The western species under the Indian summer monsoon regime were mainly impacted by temperature factors, whereas precipitation impacted the eastern species under the East Asian summer monsoon regime. Our simulation predicted a northward range expansion of section Cyclobalanopsis between 2081 and 2100, except for the ranges of the three Himalayan species analyzed, which might shrink significantly. The greatest shift of highly suitable areas was predicted for the species in the South Pacific, with a centroid shift of over 300 km. Remarkably, only 7.56% of suitable habitat is currently inside protected areas, and the percentage is predicted to continue declining in the future. To better conserve Asian EBLFs, establishing nature reserves in their northern distribution ranges, and transplanting the populations with predicted decreasing numbers and degraded habitats to their future highly suitable areas, should be high-priority objectives.

Electronic exoneuron based on liquid metal for the quantitative sensing of the augmented somatosensory system.

The increasing demands in augmented somatosensory have promoted quantitative sensing to be an emerging need for athletic training/performance evaluation and physical rehabilitation. Neurons for the somatosensory system in the human body can capture the information of movements in time but only qualitatively. This work presents an electronic Exo-neuron (EEN) that can spread throughout the limbs for realizing augmented somatosensory by recording both muscular activity and joint motion quantitatively without site constraints or drift instability, even in strenuous activities. Simply based on low-cost liquid metal and clinically used adhesive elastomer, the EEN could be easily fabricated in large areas for limbs. It is thin (~120 µm), soft, stretchable (>500%), and conformal and further shows wide applications in sports, rehabilitation, health care, and entertainment.

Dynamic Path Planning of Mobile Robot Based on Improved Sparrow Search Algorithm.

Aiming at the shortcomings of the traditional sparrow search algorithm (SSA) in path planning, such as its high time-consumption, long path length, it being easy to collide with static obstacles and its inability to avoid dynamic obstacles, this paper proposes a new improved SSA based on multi-strategies. Firstly, Cauchy reverse learning was used to initialize the sparrow population to avoid a premature convergence of the algorithm. Secondly, the sine-cosine algorithm was used to update the producers' position of the sparrow population and balance the global search and local exploration capabilities of the algorithm. Then, a Lévy flight strategy was used to update the scroungers' position to avoid the algorithm falling into the local optimum. Finally, the improved SSA and dynamic window approach (DWA) were combined to enhance the local obstacle avoidance ability of the algorithm. The proposed novel algorithm is named ISSA-DWA. Compared with the traditional SSA, the path length, path turning times and execution time planned by the ISSA-DWA are reduced by 13.42%, 63.02% and 51.35%, respectively, and the path smoothness is improved by 62.29%. The experimental results show that the ISSA-DWA proposed in this paper can not only solve the shortcomings of the SSA but can also plan a highly smooth path safely and efficiently in the complex dynamic obstacle environment.

Meta-QTL analysis and in-silico transcriptome assessment for controlling chlorophyll traits in common wheat.

Chlorophyll is an important plant molecule for absorbing light and transferring electrons to produce energy for photosynthesis, which has a significant impact on crop yield. To identify quantitative trait loci (QTL) controlling chlorophyll traits in wheat (Triticum aestivum L.), a comprehensive meta-analysis of 411 original QTLs for six chlorophyll traits was performed, including the evolution of soil plant analysis development (SPAD), chlorophyll content index (CCI), chlorophyll a content (Chla), chlorophyll b content (Chlb), chlorophyll content (Chl), and ratio of chlorophyll a to b (Chla/b), derived from 41 independent experiments conducted over the past two decades. Fifty-six consensus meta-QTLs (MQTLs) were detected, unevenly distributed on chromosomes 1A, 1B, 2A, 2B, 2D, 3B, 3D, 4B, 4D, 5A, 5D, 6A, 6D, 7B, and 7D. The confidence interval (CI) of the identified MQTLs was 0.18 to 15.07 cM, with an average of 5.74 cM, and 3.17-times narrower than that of the original QTLs. A total of 30 MQTLs were aligned with marker-trait associations (MTAs) reported in genome-wide association studies (GWAS) for chlorophyll traits in wheat. Based on MQTL-flanking marker information and homology analyses combined with RNA-seq data, 136 putative candidate genes were identified in MQTL regions, involved in porphyrin metabolism, photosynthesis, terpene biosynthesis, glyoxylate and dicarboxylate metabolism, and secondary metabolites. The results of this study contribute to the understanding of the genetic basis for controlling chlorophyll traits and can be used in breeding wheat with high photosynthetic efficiency.

Linear active disturbance rejection control of servo systems via IMC principle with active damping and sliding mode techniques.

In this paper, a new linear active disturbance rejection control (LADRC) is proposed for servo systems based on active damping (AD), internal model control (IMC) and sliding mode control (SMC). The IMC rules are applied to tune the controller gains for a prescribed tracking performance. The AD method injects a virtual damping force into the motion system to actively attenuate disturbances. By deriving the sliding dynamics of IMC, a boundary layer solution of SMC is employed to enhance the robustness of control system. As the improved robust IMC scheme is applied as the controller of LADRC, the uncompensated disturbance of linear extended state observer can be better suppressed. With this method, a higher tracking control accuracy is expected to be obtained in the presence of uncertain dynamics. Theoretical stability was analyzed based on the Lyapunov method. Comparative experiments were conducted on a permanent magnet synchronous motor to validate the superiority of the proposed approach.

What Counts? Sources of Knowledge in Children's Acquisition of the Successor Function.

Although many U.S. children can count sets by 4 years, it is not until 5½-6 years that they understand how counting relates to number-that is, that adding 1 to a set necessitates counting up one number. This study examined two knowledge sources that 3½- to 6-year-olds (N = 136) may leverage to acquire this "successor function": (a) mastery of productive rules governing count list generation; and (b) training with "+1" math facts. Both productive counting and "+1" math facts were related to understanding that adding 1 to sets entails counting up one number in the count list; however, even children with robust successor knowledge struggled with its arithmetic expression, suggesting they do not generalize the successor function from "+1" math facts.

A New Trajectory Determination Method for Robot-Assisted Ankle Ligament Rehabilitation.

Keeping ligament strain at an appropriate range is beneficial for avoiding unexpected injuries and enhancing treatment efficacy. This study proposes a new trajectory determination method specifically for the robot-assisted ankle ligament rehabilitation. The input of this method is a set of strain constraints of certain ligaments and the output is the detailed training trajectory. Simulations were conducted with two cases (one-ligament injury and three-ligaments injury). While this method has not been experimentally tested, on condition of an accurate ligament kinematics assessment, ligament strain can be guaranteed to be within the specified range following the derived trajectory. This method can help design injury-specific treatment protocols and has potential in improving the effectiveness of robot-assisted ankle rehabilitation. Future work will verify the validity and the practicality, and consider the improvement of the method.