To mimic the performance of the tandem solar cells, ternary blend solar cells with a single active layer of P3HT:PCPDTBT:PC sub(61)BM were cast from chlorobenzene and thermally annealed. By varying ...blending ratio, thermal annealing time and P3HT molecular weight, the device performance was enhanced relative to the binary references. To understand this, the morphology of the active layer was studied using hard and soft X-ray scattering methods in concert with bright field and energy resolved transmission electron microscopies. We found that the phase separation of the amorphous PCPDTBT and P3HT guided the formation of P3HT fibrils, resulting in a unique multi-length-scale morphology. This morphology consisted of bundles of well-defined P3HT fibrils, forming a network, imbedded in an amorphous mixture of the PCBM, PCPDTBT and P3HT. The two polymers acted independently in their specific photoactive ranges, and the sensitization of PCPDTBT benefited the cascade charge transfer. This multi-length-scale morphology was linked to the improved device performance of P3HT:PCPDTBT:PC sub(61)BM and the photophysics of the active layer.
Object detection is essential to timely restore the video, especially over the complex underwater environment. We propose a novel moving object detection algorithm with dynamic mode decomposition ...(DMD) and Yolov5. First, DMD is exploited to compress and retrieve the dynamic foreground and the static background by decomposing the snapshot sequence matrix into a low-rank and a sparse matrices, respectively. Then, the foreground video is retrieved from the low-rank matrix and the reconstructed matrix is recovered together by the two matrices. Finally, the moving object buried in the dynamic foreground and reconstructed images or videos are recognized by Yolov5. Experiments reveal that both the foreground and the reconstructed videos have higher detection accuracy than the Yolov5. Also, compared with the original video, the proposed algorithm bears the advantages of improved detection accuracy, lower compressing rate and decreased computing cost.
Hyoscyamine and scopolamine (HS), two valuable tropane alkaloids of significant medicinal importance, are found in multiple distantly related lineages within the Solanaceae family. Here we sequence ...the genomes of three representative species that produce HS from these lineages, and one species that does not produce HS. Our analysis reveals a shared biosynthetic pathway responsible for HS production in the three HS-producing species. We observe a high level of gene collinearity related to HS synthesis across the family in both types of species. By introducing gain-of-function and loss-of-function mutations at key sites, we confirm the reduced/lost or re-activated functions of critical genes involved in HS synthesis in both types of species, respectively. These findings indicate independent and repeated losses of the HS biosynthesis pathway since its origin in the ancestral lineage. Our results hold promise for potential future applications in the artificial engineering of HS biosynthesis in Solanaceae crops.
Resin-based pit-and-fissure sealants are often used to form a barrier on the occlusal surface of molars to treat caries lesions; however, bacteria can remain in the pit and fissures without ...detection, increasing the risk of secondary caries. Sealants with antimicrobial properties or microbial repellent actions might be advantageous. The aim of this study was to assess the inhibitory effect of a 2-methacryloxylethyl dodecyl methyl ammonium bromide (MAE-DB)-incorporated sealant against Streptococcus mutans. MAE-DB (4% wt) was incorporated into a commercially available sealant, Eco-S resin-based pit-and-fissure sealant (Vericom Co., Ltd., Korea); a sealant without MAE-DB served as a negative control, and Clinpro™ Sealant (3M™ ESPE™), a fluoride-releasing resin, was used as a commercial control. The effects of the cured sealants and their eluents on the growth of S. mutans were determined according to colony-forming unit counts and metabolic tests. The effects of the cured sealants on the adherence and membrane integrity of S. mutans were investigated using confocal laser-scanning microscopy (CLSM) in conjunction with fluorescent indicators. Compared with the negative control and commercial control, the cured MAE-DB-incorporated pit-and-fissure sealant exhibited a significant inhibitory effect on the growth of S. mutans (P < 0.05), whereas the eluents did not show any detectable antibacterial activity. The commercial control also showed no detectable bactericidal activity. Moreover, the aged experimental material retained its property of contact inhibition of biofilm formation. The fluorescence analysis of CLSM images demonstrated that the cured MAE-DB-incorporated sealant could hamper the adherence of S. mutans and exert a detrimental effect on bacterial membrane integrity. The incorporation of MAE-DB can render a pit-and-fissure sealant with contact antibacterial activity after polymerization via influencing the growth, adherence, and membrane integrity of S. mutans. Therefore, MAE-DB-containing pit-and-fissure sealant shows promise for preventing or controlling dental caries on occlusal pit and fissures of molars.
With the rapid advances in metal halide perovskite optoelectronics, eliminating toxic lead from perovskites has been an urgent demand. However, state-of-the-art lead-free perovskite photodetectors ...are still challenged with issues of low photoresponse, poor stability, etc. Here, all-inorganic lead-free perovskite (Cs3Cu2I5) single crystals that possess good stability under air exposure are synthesized via a facile solid reaction method. Meanwhile, a higher photoluminescence quantum yield of 95.2% and a prolonged carrier lifetime of 1.127 μs are obtained by further optimizing the synthesis. Benefiting from the polyporous surface and hollow structure of Cu-7,7,8,8-tetracyanoquinodimethane (CuTCNQ) microtubes, more Cs3Cu2I5 nanocrystals can adhere on the innershell and outershell of CuTCNQ-15 microtubes. This unique structure contributes to the improved efficiency of utilizing incident light and promotes charge carrier generation and transportation. As a result, the hierarchical CuTCNQ/Cs3Cu2I5 (hollow microtube/nanocrystal) heterostructure phototransistor exhibits a high responsivity of 88.36 A W–1 and a large detectivity of 1.66 × 1012 Jones. The proposed lead-free perovskites and mixed-dimensional heterojunctions are promising for sensitive light detection.
Automated essay scoring aims to evaluate the quality of an essay automatically. It is one of the main educational applications in the field of natural language processing. Recently, the research ...scope has been extended from prompt-special scoring to cross-prompt scoring and further concentrating on scoring different traits. However, cross-prompt trait scoring requires identifying inner-relations, domain knowledge, and trait representation as well as dealing with insufficient training data for the specific traits. To address these problems, we propose a RDCTS model that employs contrastive learning and utilizes Kullback–Leibler divergence to measure the similarity of positive and negative samples, and we design a feature fusion algorithm that combines POS and syntactic features instead of using single text attribute features as input for the neural AES system. We incorporate implicit data augmentation by adding the dropout layer to the word level and sentence level of the hierarchical model to mitigate the effects of limited data. Experimental results show that our RDCTS achieves state-of-the-art performance and greater consistency.
Long non-coding RNAs (lncRNAs) play a vital role in a variety of biological functions in plant growth and development. In this study, we provided an overview of the molecular mechanisms of lncRNAs in ...interacting with other biomolecules with an emphasis on those lncRNAs validated only by low-throughput experiments. LncRNAs function through playing multiple roles, including sponger for sequestering RNA or DNA, guider or decoy for recruiting or hijacking transcription factors or peptides, and scaffold for binding with chromatin modification complexes, as well as precursor of microRNAs or small interfering RNAs. These regulatory roles have been validated in several plant species with a comprehensive list of 73 lncRNA–molecule interaction pairs in 16 plant species found so far, suggesting their commonality in the plant kingdom. Such initial findings of a small number of functional plant lncRNAs represent the beginning of what is to come as lncRNAs with unknown functions were found in orders of magnitude more than proteins.
Carbon and water fluxes in ecosystems are tightly coupled by gas diffusion through stomata. However, carbon–water (C–W) relationships vary largely across time scales, vegetation types, and regions. ...Subtropical forests in China play an important role in the global carbon and water cycles, yet studies of C–W relationships in this region remain limited. Here, we investigated summer-time C–W relationships in this region at two subtropical sites: the evergreen broadleaved forest at Dinghushan (23.17° N, 112.53° E, 300 m) and the evergreen coniferous forest at Qianyanzhou (26.74° N, 115.06° W, 106 m), using the flux tower data from the FLUXNET2015. The C–W relationship was examined using two measures. The first was daily water use efficiency (WUE), which is the ratio of daily gross primary productivity (GPP) to evapotranspiration (ET). The second was the correlation coefficient (r) of hourly GPP and ET. Our analysis showed that the daily WUE in the two forests ranged over 4–14 mg CO2 per g H2O, higher in the coniferous forest than in the broadleaved forest. The mean values of r for hourly C–W coupling were similar at the two forests, being 0.5–0.6, which suggests asynchronous diurnal variations in GPP and ET. Both daily WUE and r were modulated by meteorological conditions. In general, high radiation, air temperature, and humidity can reduce WUE at both sites. For the broadleaved forest, the most influential factor on WUE was VPD, followed by radiation, while in the coniferous forest, VPD, air temperature, and radiation were almost equally important. For hourly C–W coupling, VPD plays a significant role. The drier the air is, the weaker the coupling in the two forests. The daily WUE and hourly C–W coupling reflect the C–W relationship from different perspectives. Both showed the strongest response to VPD but with different sensitivity.
•CNT/CB based composite shows a large and stable sensing response.•Contrasting sensitivity in toluene/water and tetrahydrofuran/water cycles is found.•The sensing device is designed to monitor ...toluene contaminations on water.
Sensor technology is significant to monitor organic contaminations on water for the present industries. In this letter, highly sensitive carbon nanotube (CNT) based silicone rubber composites (CNTRs) are used as the candidate for sensing materials, which yet display unstable liquid sensing outputs owing to poor dispersion of CNTs. As hybrid carbon blacks (CBs) are added, CNT/CB composites are prepared to solve bad distribution of CNTs. CNT/CB composites achieve a better conductivity, larger sensing capacity and more stable sensing response on singular chemical liquids than CNTR. Importantly, growing resistance responsivities are discovered as CNT/CB composites circularly contact toluene and water. We therefore design the sensing application to monitor toluene suspensions on water.
Label Distribution Learning (LDL) is a machine learning paradigm which is recently proposed to deal with the more ambiguity label. This paradigm assigns the distribution-level label to an instance so ...that it can exploit the relative importance of every candidate labels to a particular instance. Previous studies always concentrate on the methods under strong supervision, which requires a large number of tagged training data. In real-world applications, it is usually difficult to collect numerical precise labels owing to the large costs in labor and time spent on the label annotation. To this end, this paper proposes a novel algorithm named Semi-SupervisedLabelDistributionLearning withCo-regularization (S2LDL-CO). To benefit from all available information, ensemble of two different models is utilized to deal with the labeled and unlabeled data, respectively. More specifically, the co-regularization framework is adopted to combine these two different models, which can process both the labeled and unlabeled data with good robustness and consistency. What’s more, manifold regularization and l2,1-norm are also added into the objective function, which can fully exploit the implicit information in instances. Finally, the well-designed objective function is optimized by an Alternating Direction of Method of Multipliers (ADMM) algorithm. Experimental results tested on thirteen benchmark datasets illustrate its effectiveness over several state-of-the-art methods.
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