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The synergistic effect that arises from blending functional agents with ordered fiber orientated structures is a noteworthy strategy to improve the mechanical properties, flexibility and waterproof performance of polylactic acid microfibrous fabrics. A promising polylactic acid/polyethylene glycol@erucamide (PLA/PEG@Era) microfibrous fabric with an ordered fiber orientation was successfully prepared by blending Era with PLA, followed by composite preparation processes of melt blowing and stretching. The results of the study revealed that the blended PLA/PEG@Era polymer with an Era mass ratio of 1.5% exhibited a higher relative degree of crystallinity of about 18.64% in comparison to the PLA/PEG polymer with a crystallinity degree of 2.24%. Moreover, the prepared fabrics exhibited a pleasant microfibrous nonwoven structure with an ordered, regular and a compensating fiber distribution, obtained by facile tailing of the stretching ratio. Also, the samples showed a high tensile breaking strength of 41.1 N with a good vapor permeability, ranging from 2537.2 g/(m2·day) to 2136.9 g/(m2·day), in addition to its excellent waterproof performance and softness. The study provides sufficient evidence that the developed PLA/PEG@Era microfibrous fabrics are extremely suitable candidates for packaging and outdoor clothing applications. [ABSTRACT FROM AUTHOR]

The multi-view of an object can be used for 3D reconstruction. The method proposed in this paper generates the left and the top view of a target car through deep learning. The input of the method is only a front view of a 3D car and it isn't necessary for the depth of the 3D car. Firstly, a rough orthographic views of the 3D car is gotten from an information constraint network which is constructed by considering the structural relation between one view and the other two views. And then the rough orthographic views is transformed into large-pixel block rough view through the nearest interpolation, at the same time, the large-pixel blocks are also migrated to improve the quality of the rough orthographic views. Finally, the generative adversarial network with perception loss is used to enhance the large-pixel block view. In addition, the three views generated by the network can be used to synthesize a 3D point cloud shell. [ABSTRACT FROM AUTHOR]

Densified SiC ceramics were prepared by using gel-casting method combined with liquid-phase sintering (LPS). In this study, a low-toxicity gel-casting system based on 2-hydroxyethyl methacrylate (HEMA) and N, N′-methylene acrylamide (MBAM) as monomer and crosslinker respectively, was first applied to SiC fabrication. The effects of the processing parameters on gel-casting were investigated in detail to achieve optimized rheological behavior and green body strength. The best result was obtained in the slurry with solid content of 50 vol%, dispersant of 0.4 wt% and monomer/crosslinker ratio of 20 at pH10. With the modified ternary sintering aids (Al 2 O 3 –Y 2 O 3 –CeO 2) added, the densification can be realized at low temperature. After pressureless sintering at 1850 °C for 2 h, the sample with best mechanical properties was obtained. The highest relative density, hardness, flexural strength and fracture toughness were 96.23%, 24.94 GPa, 423.95 MPa and 4.78 MPa/m1/2, respectively. Present work provides an environmentally friendly and energy-saving process for preparing SiC ceramics with excellent properties. [ABSTRACT FROM AUTHOR]

Iodine is a well-known oxidant that is widely used in organic syntheses. Thiol oxidation by stoichiometric iodine is one of the most commonly employed strategies for the synthesis of valuable disulfides. While recent advancements in catalytic aerobic oxidation conditions have eliminated the need for stoichiometric oxidants, concerns persist regarding the use of toxic or expensive catalysts. In this study, we discovered that iodine can be used as a cheap, low-toxicity catalyst in the aerobic oxidation of thiols. In the catalytic cycle, iodine can be regenerated via HI oxidation by O2 at 70 °C in EtOAc. This protocol harnesses sustainable oxygen as the terminal oxidant, enabling the conversion of primary and secondary thiols with remarkable efficiency. Notably, all 26 tested thiols, encompassing various sensitive functional groups, were successfully converted into their corresponding disulfides with yields ranging from >66% to 98% at a catalyst loading of 5 mol%. [ABSTRACT FROM AUTHOR]

High-brightness laser lighting requires high luminous efficacy and high thermal performance of luminescent materials. In this study, we designed and fabricated single-phase YAG:Ce ceramics with differential grain sizes by combining the coarse commercial phosphor and fine powder of precusor. The large YAG:Ce grains mainly contribute to excellent luminescence properties. The small YAG:Ce grains not only change the direction of light propagation to improve the luminous efficiency but also effectively increase the Ce3+ content to improve the absorption of blue light, which significantly further enhance the luminescence properties compared with the second phase in the YAG:Ce-base composite ceramics. The luminescent ceramic with 40 wt% large grains sintered under 1550 °C has the highest luminous efficacy of 398.5 lm/W. Compared with the Al 2 O 3 –YAG:Ce composite ceramic, the single-phase YAG:Ce ceramic effectively increased the absorption of blue light to enhance the luminescence properties without the adverse effects caused by the transverse scattering of light in the Al 2 O 3 phase. After encapsulating the ceramic onto a radiator, a high luminous flux of 7697.6 lm under the blue-laser excitation of 3.0 A (54.6 W) was obtained. These indicated its broad application prospects in high-power solid-state laser lighting. [ABSTRACT FROM AUTHOR]

We discovered that highly regioselective H/D exchange can be achieved on the α‐position of the pentafluorophenyl (Pfp) ester using Et3N as the catalyst and D2O as the deuterium source. Our computational and experimental results showed that the Pfp group can significantly increase the acidity of the α‐hydrogen of the ester. This mild reaction condition tolerated a variety of functional groups. 90%∼98% yields and 91%∼98% deuterium incorporations were obtained with all the tested Pfp esters. Taking advantage of the high reactivity of Pfp esters, a series of valuable α‐deuterio carboxylic acid derivatives, including herbicide, drugs and drug intermediates, have been synthesized using α‐deuterio Pfp esters as precursors. [ABSTRACT FROM AUTHOR]

This paper presents a self-supervised learning network called SP-Flow to generate keypoints in real-time for SLAM systems. Optical flows are employed to match the keypoints between two successive frames in the training process of SP-Flow. This approach enables the network to use datasets without manual annotations. To show the efficacy of our SP-Flow, we built an SP-Flow SLAM system by replacing ORB with SP-Flow in the ORB-SLAM2 system. The experimental results demonstrate that our SLAM system is able to achieve real-time performance and high accuracy with stereo or RGB-D images as inputs. • A self-supervised framework is used for SP-Flow network training. • The keypoints classified by the optical flow are considered when constructing the loss functions. • A keypoint extractor suitable for SLAM is proposed. • The robustness of SLAM in low-texture environments is improved. [ABSTRACT FROM AUTHOR]

Regional tectonic uplift information is recorded by knickpoints distributed in multiple rivers. The changing base level (mainstream) caused by tectonic uplift also controls karst development. Groundwater should drain as springs near the base level due to karstification usually occurring near the base level, but some drains were higher than the present river in the canyon. The assumption is proposed that the spring is more elevated than the current river formed at the older intermittent stage in uplift processes and that knickpoints at the elevation can correspond to the springs. A typical basin south of Daba Mountain is selected to identify the assumption. Three knickpoints with 11 karst landforms suggest that knickpoints can indicate the karst development elevation in the basin. This method is promoted to 29 basins around Daba Mountain which are separated into DTB (North Daba Mountain Pre-Land Thrust Fault Belt) representing north part and DFB (South Daba Mountain Pre-Land Fold Belt) representing south part to verify the effectiveness of the assumption. The result discovers that the knickpoints and karst landforms have a similar high-frequency elevation interval in DFB and little variance in DTB. The reason may be that DFB has better karstification conditions, including precipitation and carbonate rock cover area, than DTB. Knickpoints is an effective indicator for karst development in area that has sufficient karstification condition like DFB. This study may provide a new perspective on the relationship between karst development and tectonic uplift and a method to find the karst groundwater drain elevation. [ABSTRACT FROM AUTHOR]

Heterotopic ossification (HO) comprises the abnormal formation of ectopic bone in extraskeletal soft tissue. The factors that initiate HO remain elusive. Herein, we found that calcified apoptotic vesicles (apoVs) led to increased calcification and stiffness of tendon extracellular matrix (ECM), which initiated M2 macrophage polarization and HO progression. Specifically, single‐cell transcriptome analyses of different stages of HO revealed that calcified apoVs were primarily secreted by a PROCR+ fibroblast population. In addition, calcified apoVs enriched calcium by annexin channels, absorbed to collagen I via electrostatic interaction, and aggregated to produce calcifying nodules in the ECM, leading to tendon calcification and stiffening. More importantly, apoV‐releasing inhibition or macrophage deletion both successfully reversed HO development. Thus, we are the first to identify calcified apoVs from PROCR+ fibroblasts as the initiating factor of HO, and might serve as the therapeutic target for inhibiting pathological calcification. [ABSTRACT FROM AUTHOR]

EN1 encodes a homeodomain-containing transcription factor and is a determinant of bone density and fracture. Previous powerful genome-wide association studies (GWASs) have identified multiple single-nucleotide polymorphisms (SNPs) near EN1 at 2q14.2 locus for osteoporosis, but the causal SNPs and functional mechanisms underlying these associations are poorly understood. The target genes regulated by the transcription factor EN1 are also unclear. In this study, we identified rs188303909, a functional CpG-SNP, as a causal SNP for osteoporosis at 2q14.2 through the integration of functional and epigenomic analyses. Functional experiments demonstrated that unmethylated rs188303909 acted as a strong allele-specific distal enhancer to regulate EN1 expression by modifying the binding of transcription factor E2F6, but rs188303909 methylation attenuated the active effect of E2F6 on EN1 expression. Importantly, transcription factor EN1 could differentially bind osteoporosis GWAS lead SNPs rs4869739-T and rs4355801-G to upregulate CCDC170 and COLEC10 expression, thus promoting bone formation. Our study provided a mechanistic insight into expression regulation of the osteoporosis susceptibility gene EN1, which could be a potential therapeutic target for osteoporosis precision medicine. Key messages: CpG-SNP rs188303909 is a causal SNP at the osteoporosis susceptibility locus 2q14.2. Rs188303909 distally regulates EN1 expression by modulating DNA methylation and E2F6 binding. EN1 upregulates CCDC170 and COLEC10 expression through osteoporosis GWAS lead SNPs rs4869739 and rs4355801. [ABSTRACT FROM AUTHOR]

The silent information regulator T1 (SIRT1) is linked to longevity and is a crucial mediator of osteoblast function. We investigated the direct role of Sirt1 during bone modeling and remodeling stages in vivo using Tamoxifen-inducible osteoblast-specific Sirt1 conditional knockout (cKO) mice. cKO mice exhibited lower trabecular and cortical bone mass in the distal femur. These phenotypes were coupled with lower bone formation and bone resorption. Metabolomics analysis revealed that the metabolites involved in glycolysis were significantly decreased in cKO mice. Further analysis of the quantitative acetylome revealed 11 proteins with upregulated acetylation levels in both the femur and calvaria of cKO mice. Cross-analysis identified four proteins with the same upregulated lysine acetylation site in both the femur and calvaria of cKO mice. A combined analysis of the metabolome and acetylome, as well as immunoprecipitation, gene knockout, and site-mutation experiments, revealed that Sirt1 deletion inhibited glycolysis by directly binding to and increasing the acetylation level of Glutamine oxaloacetic transaminase 1 (GOT1). In conclusion, our study suggested that Sirt1 played a crucial role in regulating osteoblast metabolism to maintain bone homeostasis through its deacetylase activity on GOT1. These findings provided a novel insight into the potential targeting of osteoblast metabolism for the treatment of bone-related diseases. [ABSTRACT FROM AUTHOR]

Detection of subsurface hydrodynamic anomalies plays a significant role in groundwater resource management and environmental monitoring. In this paper, based on data from the groundwater level, atmospheric pressure, and precipitation in the Chengdu area of China, a method for detecting outliers considering the factors affecting groundwater levels is proposed. By analyzing the factors affecting groundwater levels in the monitoring site and eliminating them, simplified groundwater data is obtained. Applying sl-Pauta (self-learning-based Pauta), iForest (Isolated Forest), OCSVM (One-Class SVM), and KNN to synthetic data with known outliers, testing and evaluating the effectiveness of 4 technologies. Finally, the four methods are applied to the detection of outliers in simplified groundwater levels. The results show that in the detection of outliers in synthesized data, the OCSVM method has the best detection performance, with a precision rate of 88.89%, a recall rate of 91.43%, an F1 score of 90.14%, and an AUC value of 95.66%. In the detection of outliers in simplified groundwater levels, a qualitative analysis of the displacement data within the field of view indicates that the outlier detection performance of iForest and OCSVM is better than that of KNN. The proposed method for considering the factors affecting groundwater levels can improve the efficiency and accuracy of detecting outliers in groundwater level data. [ABSTRACT FROM AUTHOR]

Detection of subsurface hydrodynamic anomalies plays a significant role in groundwater resource management and environmental monitoring. In this paper, based on data from the groundwater level, atmospheric pressure, and precipitation in the Chengdu area of China, a method for detecting outliers considering the factors affecting groundwater levels is proposed. By analyzing the factors affecting groundwater levels in the monitoring site and eliminating them, simplified groundwater data is obtained. Applying sl-Pauta (self-learning-based Pauta), iForest (Isolated Forest), OCSVM (One-Class SVM), and KNN to synthetic data with known outliers, testing and evaluating the effectiveness of 4 technologies. Finally, the four methods are applied to the detection of outliers in simplified groundwater levels. The results show that in the detection of outliers in synthesized data, the OCSVM method has the best detection performance, with a precision rate of 88.89%, a recall rate of 91.43%, an F1 score of 90.14%, and an AUC value of 95.66%. In the detection of outliers in simplified groundwater levels, a qualitative analysis of the displacement data within the field of view indicates that the outlier detection performance of iForest and OCSVM is better than that of KNN. The proposed method for considering the factors affecting groundwater levels can improve the efficiency and accuracy of detecting outliers in groundwater level data. [ABSTRACT FROM AUTHOR]

Deuterated polymers have wide applications but limited synthetic methods. In this study, we report an efficient two-step approach for the synthesis of deuterated polyesters and polyurethanes. Firstly, two practical single-electron transfer (SET) reductive-deuteration methods have been developed for site-selective introduction of C(sp3)–D into diol monomers. Nine deuterated diol monomers with high deuterium incorporations were synthesized under SmI2 –D2 O and/or Na-EtOD- d 1 SET reductive-deuteration conditions. Then, six typical deuterated polyesters and polyurethanes were synthesized using those deuterated monomers under typical polymerization conditions. In all the synthesized polymers, high deuterium incorporation was fully maintained, which showcased the potential application of this approach for the synthesis of polymers with site-specific deuterium labelling. [ABSTRACT FROM AUTHOR]

The generation of walking patterns is central to bio-inspired robotics and has been attained using methods encompassing diverse numerical as well as analog implementations. Here, we demonstrate the possibility of synthesizing viable gaits using a paradigmatic low-dimensional non-linear entity, namely, the Rössler system, as a dynamical unit. Through a minimalistic network wherein each instance is univocally associated with one leg, it is possible to readily reproduce the canonical gaits as well as generate new ones via changing the coupling scheme and the associated delays. Varying levels of irregularity can be introduced by rendering individual systems or the entire network chaotic. Moreover, through tailored mapping of the state variables to physical angles, adequate leg trajectories can be accessed directly from the coupled systems. The functionality of the resulting generator was confirmed in laboratory experiments by means of an instrumented six-legged ant-like robot. Owing to their simple form, the 18 coupled equations could be rapidly integrated on a bare-metal microcontroller, leading to the demonstration of real-time robot control navigating an arena using a brain–machine interface. [ABSTRACT FROM AUTHOR]

The YAG:Ce3+, Mn2+ transparent ceramic with red emitting component, was successfully prepared by gel-casting forming technique for the first time. A stable slurry with 55 vol% solid loading and low viscosity was prepared at pH 9.5 with 2.5 wt% dispersant content (based on the weight of YAG:Ce3+, Mn2+ powders). After casting, drying, and pre-sintering, vacuum sintering was performed at 1750 °C for 10 h. The result showed that the green body had no deformation and exhibited homogeneous. The average grain size was 15 μm, and the grain boundary was clean without any impurities observed. Finally, high optical quality YAG:Ce3+, Mn2+ ceramic was obtained. The emission spectra of YAG:Ce3+, Mn2+ ceramic sheets are obviously red-shifted which improve the color rendering performance of white LEDs. [ABSTRACT FROM AUTHOR]