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Abstract Near-infrared (NIR) phosphors based on Cr3+ doped garnets present great potential in the next generation of NIR light sources. Nevertheless, the huge searching space for the garnet composition makes the rapid discovery of NIR phosphors with high performance remain a great challenge for the scientific community. Herein, a generalizable machine learning (ML) strategy is designed to accelerate the exploration of innovative NIR phosphors via establishing the relationship between key parameters and emission peak wavelength (EPW). We propose a semi-supervised co-training model based on kernel ridge regression (KRR) and support vector regression (SVR), which successfully establishes an expanded dataset with unlabeled dataset (previously unidentified garnets), addressing the overfitting issue resulted from a small dataset and greatly improving the model generalization capability. The model is then interpreted to extract valuable insights into the contribution originated from different features. And a new type NIR luminescent material of Lu3Y2Ga3O12: Cr3+ (EPW~750 nm) is efficiently screened, which demonstrates a high internal (external) quantum efficiency of 97.1% (38.8%) and good thermal stability, particularly exhibiting promising application in the NIR phosphor-converted LEDs (pc-LED). These results suggest the strategy proposed in this work could provide new viewpoint and direction for developing NIR luminescence materials.

Purple-fleshed sweetpotato (PFSP) (Ipomoea batatas (L.) Lam), whose flesh is purple to dark purple, is a special variety type of sweetpotato, which has the characteristics of food crop, industrial crop and medicinal crop. The storage root (SR) of PFSP is rich in anthocyanins, starch, protein, soluble sugar, mineral elements, polyphenol, dietary fiber and so on, which has balanced and comprehensive nutritional value. And in recent years, its unique nutritional elements are increasingly known for their health functions. At present, there is no article on the characteristics and quality analysis of industrial xz8 variety. To explore the influence of different environments on the processing quality of xz8, we selected nine regions (Xuzhou, Jiawang, Pizhou, Xinyi, Peixian, Sihong, Yanchen, Xiangyang and Tianshui) to measure its yield and quality changes. The data demonstrated that xz8 has a very consistent high yield performance. In Tianshui, the anthocyanins, protein and minerals contents were significantly higher and yield also above average. Moreover, the variety with the lowest starch content exhibited the best taste. On the basis of the above results, it suggested that quite practicable to promote xz8 cultivation and suitable for processing in these areas. Thus, our present findings improve our understanding of xz8 variety and provide the basis for the industrial production of PFSP with strong prospects for success.

Flavonol synthase (FLS) is a key enzyme of the flavonoid biosynthetic pathway, which catalyzes the conversion of dihydroflavonols into flavonols. In this study, the FLS gene IbFLS1 was cloned and characterized from sweet potato. The resulting IbFLS1 protein showed a high similarity with other plant FLSs. The conserved amino acids (HxDxnH motifs) binding ferrous iron and residues (RxS motifs) binding 2-oxoglutarate were found in IbFLS1 at conserved positions, as in other FLSs, suggesting that IbFLS1 belongs to the 2-oxoglutarate-dependent dioxygenases (2-ODD) superfamily. qRT-PCR analysis showed an organ-specific pattern of expression of the IbFLS1 gene, which was predominantly expressed in young leaves. The recombinant IbFLS1 protein could catalyze the conversion of dihydrokaempferol and dihydroquercetin to kaempferol and quercetin, respectively. The results of subcellular localization studies indicated that IbFLS1 was found mainly in the nucleus and cytomembrane. Furthermore, silencing the IbFLS gene in sweet potato changed the color of the leaves to purple, substantially inhibiting the expression of IbFLS1 and upregulating the expression of genes involved in the downstream pathway of anthocyanin biosynthesis (i.e., DFR, ANS, and UFGT). The total anthocyanin content in the leaves of the transgenic plants was dramatically increased, whereas the total flavonol content was significantly reduced. Thus, we conclude that IbFLS1 is involved in the flavonol biosynthetic pathway and is a potential candidate gene of color modification in sweet potato.

In real scenes, due to the problems of low light and unsuitable views, the images often exhibit a variety of degradations, such as low contrast, color distortion, and noise. These degradations affect not only visual effects but also computer vision tasks. This paper focuses on the combination of traditional algorithms and machine learning algorithms in the field of image enhancement. The traditional methods, including their principles and improvements, are introduced from three categories: gray level transformation, histogram equalization, and Retinex methods. Machine learning based algorithms are not only divided into end-to-end learning and unpaired learning, but also concluded to decomposition-based learning and fusion based learning based on the applied image processing strategies. Finally, the involved methods are comprehensively compared by multiple image quality assessment methods, including mean square error, natural image quality evaluator, structural similarity, peak signal to noise ratio, etc.

As an important characteristic crop in China, sweetpotato plays an important role in the intake and supplement of nutrients. The saccharification characteristics of sweetpotato determine the edible quality and processing type. Exploring the saccharification characteristics of sweetpotato is of great significance to the selection of processing materials and the formation mechanism of service quality, but there are few relevant studies. A comparison study of two high saccharification varieties (Y25 and Z13) and one low saccharification variety (X27) was conducted to analyze their storage roots physical and chemical properties. The results show that the dry matter content, starch, and amylose content of Y25 and Z13 were significantly different from those of X27. Furthermore, the total amylase activity was significantly higher than that of X27. On the other hand, the starch gelatinization temperature was significantly lower than that of X27. The starch reduction in Y25 and Z13 is four times more than that in X27, and the maltose content of Y25 and Z13 is more than two times that of X27. Finally, the scores of sensory evaluation and physiological sweetness were significantly higher than those of X27. The results provide a theoretical basis for understanding the saccharification characteristics of sweetpotato varieties and are of guiding significance for the selection of sweetpotato parents.

IntroductionCrops are affected by various abiotic stresses, among which heat (HT) and drought (DR) stresses are the most common in summer. Many studies have been conducted on HT and DR, but relatively little is known about how drought and heat combination (DH) affects plants at molecular level.MethodsHere, we investigated the responses of sweetpotato to HT, DR, and DH stresses by RNA-seq and data-independent acquisition (DIA) technologies, using controlled experiments and the quantification of both gene and protein levels in paired samples.ResultsTwelve cDNA libraries were created under HT, DR, and DH conditions and controls. We identified 536, 389, and 907 DEGs in response to HT, DR, and DH stresses, respectively. Of these, 147 genes were common and 447 were specifically associated with DH stress. Proteomic analysis identified 1609, 1168, and 1535 DEPs under HT, DR, and DH treatments, respectively, compared with the control, of which 656 were common and 358 were exclusive to DH stress. Further analysis revealed the DEGs/DEPs were associated with heat shock proteins, carbon metabolism, phenylalanine metabolism, starch and cellulose metabolism, and plant defense, amongst others. Correlation analysis identified 6465, 6607, and 6435 co-expressed genes and proteins under HT, DR, and DH stresses respectively. In addition, a combined analysis of the transcriptomic and proteomic data identified 59, 35, and 86 significantly co-expressed DEGs and DEPs under HT, DR, and DH stresses, respectively. Especially, top 5 up-regulated co-expressed DEGs and DEPs (At5g58770, C24B11.05, Os04g0679100, BACOVA_02659 and HSP70-5) and down-regulated co-expressed DEGs and DEPs (AN3, PMT2, TUBB5, FL and CYP98A3) were identified under DH stress.DiscussionThis is the first study of differential genes and proteins in sweetpotato under DH stress, and it is hoped that the findings will assist in clarifying the molecular mechanisms involved in sweetpotato resistance to heat and drought stress.

Image registration is a fundamental and important task in remote sensing. In this article, we focus on feature-based image registration. Existing attempts often require estimating a transformation model or imposing relaxed geometric constraints to establish reliable feature correspondences. However, a parametric model cannot handle image pairs undergoing complex transformations, and relaxed methods discard a lot of structure information and the results are often coarse. To solve the above issues, we propose a local structure visualization descriptor to preserve the original structure information, and cast the feature matching task into an evaluation of the consensus of visual structure under a convolutional neural network. This strategy can effectively measure the similarity of neighborhood structure for mismatch removal. In summary, our method does not depend on a specific transformation model and can process arbitrary remote sensing images (e.g., different deformations, severe outliers, various rotations, and scaling changes). To demonstrate the robustness of our strategy for image registration, extensive experiments on various real remote sensing images for feature matching are conducted and compared against nine state-of-the-art methods, where our method gives the best performances in most scenarios.

The present study was undertaken to determine the scope of sweetpotato cultivation in arid regions of China. For this purpose, we investigated yield, anthocyanin compositions and physicochemical properties of starch in purple-fleshed sweetpotato (PFSP) “Xuzishu8” under humid (zi8-X) and arid (zi8-D) environments of China. The experiment was conducted in three replications in both environments during 2019 and 2020. The yield and anthocyanidins contents of PFSP were significantly higher in the arid conditions as compared to humid. Zi8-X and zi8-D both revealed the presence of three anthocyanidins, namely, cyanidin (Cy), peonidin (Pn), and pelargonidin (Pg). Cy and Pn accounted for 36.40 and 63.54% of the total anthocyanidins in zi8-X, while in zi8-D, they were found as 26.13 and 73.80%, respectively. The quantitative analysis of these anthocyanins was performed using HPLC-ESI-MS/MS which revealed eighteen anthocyanins such as nine Cy, eight Pn and one Pg. Out of which, eleven anthocyanins showed a significant difference under both conditions. Starch and amylopectin contents were found to be increased by 15.39 and 4.71%, respectively, while the amylose concentration was reduced by 15.54% under the arid environment. The diameter of the starch granule and the peak viscosity were significantly higher under arid as compared to humid conditions. On the basis of results of this study, it seems quite practicable to develop PFSP cultivation in desert regions.

Abstract Background Purple-fleshed sweetpotato (PFSP) is one of the most important crops in the word which helps to bridge the food gap and contribute to solve the malnutrition problem especially in developing countries. Salt stress is seriously limiting its production and distribution. Due to lacking of reference genome, transcriptome sequencing is offering a rapid approach for crop improvement with promising agronomic traits and stress adaptability. Results Five cDNA libraries were prepared from the third true leaf of hexaploid sweetpotato at seedlings stage (Xuzi-8 cultivar) treated with 200 mM NaCl for 0, 1, 6, 12, 48 h. Using second and third generation technology, Illumina sequencing generated 170,344,392 clean high-quality long reads that were assembled into 15,998 unigenes with an average length 2178 base pair and 96.55% of these unigenes were functionally annotated in the NR protein database. A number of 537 unigenes failed to hit any homologs which may be considered as novel genes. The current results indicated that sweetpotato plants behavior during the first hour of salt stress was different than the other three time points. Furthermore, expression profiling analysis identified 4, 479, 281, 508 significantly expressed unigenes in salt stress treated samples at the different time points including 1, 6, 12, 48 h, respectively as compared to control. In addition, there were 4, 1202, 764 and 2195 transcription factors differentially regulated DEGs by salt stress at different time points including 1, 6, 12, 48 h of salt stress. Validation experiment was done using 6 randomly selected unigenes and the results was in agree with the DEG results. Protein kinases include many genes which were found to play a vital role in phosphorylation process and act as a signal transductor/ receptor proteins in membranes. These findings suggest that salt stress tolerance in hexaploid sweetpotato plants may be mainly affected by TFs, PKs, Protein Detox and hormones related genes which contribute to enhance salt tolerance. Conclusion These transcriptome sequencing data of hexaploid sweetpotato under salt stress conditions can provide a valuable resource for sweetpotato breeding research and focus on novel insights into hexaploid sweetpotato responses to salt stress. In addition, it offers new candidate genes or markers that can be used as a guide to the future studies attempting to breed salt tolerance sweetpotato cultivars.

Flesh color (FC), skin color (SC), and anthocyanin content (AC) are three important traits being used for commodity evaluation in purple-fleshed sweet potato. However, to date, only a few reports are available on the inheritance of these traits. In this study, we used a biparental mapping population of 274 F1 progeny generated from a cross between a dark purple-fleshed (Xuzishu8) and white-fleshed (Meiguohong) sweet potato variety for genetic analyses. Correlation analysis showed a significant positive correlation among AC, SC, and FC. Medium-to-high heritability was observed for these traits. We detected single nucleotide polymorphisms (SNPs) by specific length amplified fragment sequencing (SLAF-seq) with the average sequencing depth of 51.72 and 25.76 for parents and progeny, respectively. Then we constructed an integrated genetic map consisting of 15 linkage groups (LGS) of sweet potato spanning on 2,233.66 cm with an average map distance of 0.71 cm between adjacent markers. Based on the linkage map, ten major quantitative trait loci (QTLs) associated to FC, SC, and AC were identified on LG12 between 0 and 64.97 cm distance, such as one QTL for SC and FC, respectively, which explained 36.3 and 45.9% of phenotypic variation; eight QTLs for AC, which explained 10.5–28.5% of the variation. These major QTLs were highly consistent and co-localized on LG12. Positive correlation, high heritability, and co-localization of QTLs on the same LG group confirm the significance of this study to establish a marker-assisted breeding program for sweet potato improvement.

Stress-associated protein (SAP) genes—encoding A20/AN1 zinc-finger domain-containing proteins—play pivotal roles in regulating stress responses, growth, and development in plants. They are considered suitable candidates to improve abiotic stress tolerance in plants. However, the SAP gene family in sweetpotato (Ipomoea batatas) and its relatives is yet to be investigated. In this study, 20 SAPs in sweetpotato, and 23 and 26 SAPs in its wild diploid relatives Ipomoea triloba and Ipomoea trifida were identified. The chromosome locations, gene structures, protein physiological properties, conserved domains, and phylogenetic relationships of these SAPs were analyzed systematically. Binding motif analysis of IbSAPs indicated that hormone and stress responsive cis-acting elements were distributed in their promoters. RT-qPCR or RNA-seq data revealed that the expression patterns of IbSAP, ItbSAP, and ItfSAP genes varied in different organs and responded to salinity, drought, or ABA (abscisic acid) treatments differently. Moreover, we found that IbSAP16 driven by the 35 S promoter conferred salinity tolerance in transgenic Arabidopsis. These results provided a genome-wide characterization of SAP genes in sweetpotato and its two relatives and suggested that IbSAP16 is involved in salinity stress responses. Our research laid the groundwork for studying SAP-mediated stress response mechanisms in sweetpotato.

Plant C2-domain abscisic acid-related (CAR) protein family plays an important role in plant growth, abiotic stress responses, and defense regulation. In this study, we cloned the IbCAR1 by homologous cloning method from the transcriptomic data of Xuzishu8, which is a sweet potato cultivar with dark-purple flesh. This gene was expressed in all tissues of sweet potato, with the highest expression level in leaf tissue, and it could be induced by NaCl and ABA. Subcellular localization analyses indicated that IbCAR1 was localized in the nucleus and plasma membrane. The PI staining experiment revealed the distinctive root cell membrane integrity of overexpressed transgenic lines upon salt stress. Salt stress significantly increased the contents of proline, ABA, and the activity of superoxide dismutase (SOD), whereas the content of malondialdehyde (MDA) was decreased in overexpressed lines. On the contrary, RNA interference plants showed sensitivity to salt stress. Overexpression of IbCAR1 in sweet potatoes could improve the salt tolerance of plants, while the RNAi of IbCAR1 significantly increased sensitivity to salt stress in sweet potatoes. Meanwhile, the genes involved in ABA biosynthesis, stress response, and reactive oxygen species (ROS)-scavenging system were upregulated in overexpressed lines under salt stress. Taken together, these results demonstrated that IbCAR1 plays a positive role in salt tolerance by relying on the ABA signal transduction pathway, activating the ROS-scavenging system in sweet potatoes.

Increasing demands for bio-products such as starch and anthocyanin stimulate researches towards purple-fleshed sweetpotato. Therefore, the aim of this complementary work is to identify the relationship between leaf area index, T/R value, starch and anthocyanin content in purple sweetpotato cultivar (cv “Xz3” from China) during the different growth stages. The traits were investigated every 15 days starting from 60 to 135 days after transplanting. The current data considered as a complementary for the main work “Quantifying cultivation technique and growth dynamics of purple-fleshed sweetpotato (Ipomoea batatas L.) in China” (Tang et al., 2018) [1].

The saccharification of sweetpotato storage roots is a common phenomenon in the cooking process, which determines the edible quality of table use sweetpotato. In the present study, two high saccharified sweetpotato cultivars (Y25, Z13) and one low saccharified cultivar (X27) in two growth periods (S1, S2) were selected as materials to reveal the molecular mechanism of sweetpotato saccharification treated at high temperature by transcriptome sequencing and non-targeted metabolome determination. The results showed that the comprehensive taste score, sweetness, maltose content and starch change of X27 after steaming were significantly lower than those of Y25 and Z13. Through transcriptome sequencing analysis, 1918 and 1520 differentially expressed genes were obtained in the two periods of S1 and S2, respectively. Some saccharification-related transcription factors including MYB families, WRKY families, bHLH families and inhibitors were screened. Metabolic analysis showed that 162 differentially abundant metabolites related to carbohydrate metabolism were significantly enriched in starch and sucrose capitalization pathways. The correlation analysis between transcriptome and metabolome confirmed that the starch and sucrose metabolic pathways were significantly co-annotated, indicating that it is a vitally important metabolic pathway in the process of sweetpotato saccharification. The data obtained in this study can provide valuable resources for follow-up research on sweetpotato saccharification and will provide new insights and theoretical basis for table use sweetpotato breeding in the future.

Sparse representations are widely used tools in image super-resolution (SR) tasks. In the sparsity-based SR methods, linear sparse representations are often used for image description. However, the non-linear data distributions in images might not be well represented by linear sparse models. Moreover, many sparsity-based SR methods require the image patch self-similarity assumption; however, the assumption may not always hold. In this paper, we propose a novel method for single image super-resolution (SISR). Unlike most prior sparsity-based SR methods, the proposed method uses non-linear sparse representation to enhance the description of the non-linear information in images, and the proposed framework does not need to assume the self-similarity of image patches. Based on the minimum reconstruction errors, support vector regression (SVR) is applied for predicting the SR image. The proposed method was evaluated on various benchmark images, and promising results were obtained.

The performance of current image retrieval is often influenced by the query information, which has prompted researchers to develop query expansion techniques. However, current query expansion techniques are limited to single-use and do not combine multiple query expansion techniques. This single-use query expansion often only produces suboptimal solutions and may result in poor results. Therefore, the purpose of this paper is to improve overall performance by using query expansion techniques in combination, simulating positive feedback and weight scaling allocation through multiple iterations. We propose a method called Joint—Alternating Query Extension Network to enhance overall performance. This method achieves state-of-the-art performance in CUB200-2011, SOP, and our self-collected Pu’er Tea datasets. [ABSTRACT FROM AUTHOR]

Vector serves as the fundamental element in the Attention calculation of the Vision Transformer (ViT). In the conventional ViT approach, spatial points within the feature map are treated as vectors, with each spatial point representing a point in h × w dimensions. We aim to broaden the spectrum of vectors and explore various forms, such as considering numerical values of feature map, channels, or windows as vectors for Attention calculation. We propose a hybrid ViT model named the High to Low Frequency Attention Network (HLFANet). Through Single Image Super-Resolution (SISR) experiments, it has been demonstrated that the different forms of vectors complement each other in learning and representing high and low-frequency features. Additionally, utilizing mixed attention helps mitigate the trade-off between computational cost and performance associated with window-based attention. [ABSTRACT FROM AUTHOR]

Background: The goal was to explore the cognition of diagnosis and treatment level of IgG4-related diseases mainly involving lymph nodes. Methods: The clinical manifestations, laboratory indicators, histopathology, and therapeutic effects of a patient with IgG4-RD suspected of lymphoma were analyzed and the relevant literature was reviewed. Results: Lymph node biopsy showed reactive hyperplasia of lymph node tissue. The liver biochemical indexes were abnormal and the bone marrow smear showed atypical lymphocytes. Lymph node section: IgG4+ cells > 100/HPF (IgG4/IgG > 40%). The serum IgG4 level was 17,200 mg/L, and the diagnosis was IgG4-RD. Oral glucocorticoids took effect after 2 weeks, and no significant enlargement of lymph nodes was observed. Conclusions: For the diagnosis of IgG4-RD, at present, histopathology is still the gold standard, but a single result cannot diagnose the disease. Comprehensive judgment should be made by combining clinical symptoms, serum IgG4 level and imaging results to prevent misdiagnosis and missed diagnosis, and to avoid over-diagnosis. Shortterm hormonal diagnostic therapy may be used in highly suspected patients who cannot be diagnosed. Once diagnosed, standardized medication, adhere to follow-up, regular review, to prevent recurrence and adverse drug reactions. [ABSTRACT FROM AUTHOR]