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Dermonecrotic toxin (DNT) is an important bacterial virulence factor produced by the zoonotic pathogens Bordetella bronchiseptica and Pasteurella multocida. This study aims to explore the possibility of expressing different fragments of P. multocida toxin (PMT) in the chromosome of attenuated B. bronchiseptica to generate single-component mucosal vaccine candidates. To achieve this, a 954-bp fragment (basepairs 301 ∼ 1254) of the B. bronchiseptica aroA gene was replaced with an N-terminal, 930-bp fragment (basepairs 1-930; PMTN) or a C-terminal, 900-bp fragment (base pairs 2959 ∼ 3858; PMTC) of the PMT encoding gene toxA. The resulting strains, denoted as Bb-PMTN or Bb-PMTC, expressed PMTN and PMTC, as evidenced by ELISA using polyclonal against full-length of PMT. Phenotypical analyses revealed that Bb-PMTN and Bb-PMTC grew much slower than wild type strains in tryptic soy broth. These strains also displayed significantly decreased 161-fold-virulence compared to the wildtype strains in mouse models. Intranasal immunization of Bb-PMTN and Bb-PMTC in mice induced high levels of antibodies against B. bronchiseptica and PMT, as well as IFN-γ and IL-10 in mouse sera, and most importantly, high titers of sIgA in mouse lungs. Vaccination with these two engineering strains provided 100% protection of mice against lethal challenge with B. bronchiseptica and 80%∼100% protection against lethal challenge with PMT, with Bb-PMTN exhibiting 1.25-fold greater immunogenic efficacy over Bb-PMTC. This study highlights the use of B. bronchiseptica attenuated strains as live mucosal vectors to deliver heterologous antigens.

Cervical spondylosis (CS) recognition systems provide regular screening services outside of a hospital and promote early detection and treatment of CS. However, in this paper, we propose a deep learning-based CS recognition system. Concerning the state-of-the-art and state-of-the-practice systems, the innovations of our approaches and algorithms are as follows: First, to elevate the reliance upon the sample number required for training the high-quality model, we reduce sample dimension and find optimal neural network architectures to reduce the number of model parameters to fit. Second, we incorporate multi-stream parallel network architecture search with multi-view feature extraction by converting time series classification into an image classification task. Specifically, five feature extraction methods (time-domain, frequency-domain, time-frequency domain, model-based, nonlinear feature extraction) are firstly utilized to extract features from multiple perspectives and form low-dimensional data set with multi-properties. Third, we reorganize low-dimensional data into image one representing the spatio-temporal relationship of muscle activity pattern. Finally, a multi-stream parallel network architecture search is proposed to use a bypass mechanism for optimal neural network architecture, each of which processes a kind of features mentioned above with an idea of the sparse connection of convolution neural network. The results on the real-world data set show that our CS recognition system achieves the average accuracy of 95.54%, average sensitivity of 99.09%, and average specificity of 90.00%, outperforming the state-of-the-art ones.

The quest to achieve high launching frequency and higher speed is one of the key goals for researchers in the field of underwater projectiles. Many methods have been proposed for reducing the drag force to reach higher speed, such as superhydrophobic surface, compliant surface, and so on. One of the most effective methods is supercavitating drag reduction technology, which can be used to achieve a significant reduction of hydrodynamic drag by wrapping a large, continuous cavity around the underwater projectile. To increase launching frequency and decrease drag force of underwater projectiles, a serial multi-projectiles structure based on the principle of supercavitation is proposed in this paper. However, the matching relationships of serial multiprojectiles between different conditions (cavitation number, distance between projectiles, etc.) and the drag characteristics have not been investigated, because obtaining the relationship between drag characteristics and different conditions requires simulation time and extensive calculations. In this paper, computational fluid dynamics (CFD) method and machine learning method were coupled to investigate the natural supercavitation phenomenon of the serial projectiles to reduce the computational cost and improve the simulation accuracy. Firstly, the numerical simulation model for the underwater supercavitating projectile is established and verified by experimental data. Then the evolution of the supercavitation for the serial multi-projectiles is described. In addition, the effects of different cavitation numbers and different distances between projectiles are investigated to demonstrate the supercavitation and drag reduction performance. Finally, the artificial neural network (ANN) model is established to predict the evolution of drag coefficient based on the data obtained by CFD. The results predicted by ANN are in good agreement with the data obtained by CFD. The findings provide helpful guidance for the research on the drag reduction characteristics of underwater serial projectiles. The main conclusions of the study are as follows: (1) The cavity will develop, fuse and collapse in the water and natural supercavitation phenomenon is observed when underwater serial projectiles move at a high speed. The serial multi-projectile structure can reduce the drag of the second projectile and achieve the goal of drag reduction. (2) The length and aspect ratio of supercavity around serial projectiles decrease with the decreasing of the cavitation number, and the drag coefficient of the second projectile decreases. The length and aspect ratio of supercavity decrease with the 3 decreasing of the distance between serial projectiles, and the drag coefficient of the second projectile decreases. (3) The drag coefficient of the second projectile predicted from the ANN model has a high accuracy, where the regression R2 values of training, validation, and testing samples are above 0.99. Machine learning has an obvious advantage in simplifying computational complexity and increasing computational efficiency. Furthermore, the discussion of different cases is based on static projectiles. However, in real-world applications, the movement of serial projectiles should be considered. This is the future direction for this work.

The rhizosphere microbial community is crucial to plant health. Many studies have explored the association between the rhizosphere microbiome and plant disease. However, few studies have focused on root rot in arecanut palm, a disease causing devastating effects and thus resulting in economic losses that considerably affect the development of the arecanut industry. Here, rhizosphere samples were collected from both healthy arecanut palm plants and root-rotted arecanut palm plants, and the microbial communities were analyzed using high-throughput sequencing. The root-rotted samples exhibited distinct microbial community richness, diversity, and composition compared with the healthy samples, which was associated with pH according to the Mantel test. Identified potential plant pathogens, including Proteobacteria, Bacteroidetes, Chytridiomycota, and Mortierellomycota, were significantly enriched in the root-rotted samples. In contrast, potentially beneficial plant microbes, such as Acidobacteria and Gemmatimonadetes, were significantly depleted in the root-rotted samples. Co-occurrence networks were constructed to further identify microbial relationships in the root-rotted samples. These findings revealed ecological imbalance among beneficial bacteria in the root-rotted samples. The present study therefore provides an integrated view of the association between the microbial community and root rot in arecanut palm.

There is an urgent need to explore the salt penetration and water migration in the cooked salted egg yolk (CSEY) gel. The aim of this study was to investigate the effect of salt and water on the physicochemical, structural and flavor characteristics of CSEY gel stored at 25 °C. The hardness of the yolk increased significantly (608.0 g → 2730.7 g) during storage. The results of LF-NMR showed that the free water content in the yolk gel was enhanced. The microstructure of CSEY could be observed by SEM, which showed that during storage, polyhedral particles were dispersed due to the heating process. In addition, ethyl acetate (71.9 %) was completely undetectable in the CSEY-21 d. In summary, the sample at and before 14 d of storage had good processing value. Therefore, this work would provide theoretical guidance for the low-sodium pickling of SEY (salted egg yolk) and its suitable storage methods.

Summary Background Ocular changes are traditionally associated with only a few hepatobiliary diseases. These changes are non-specific and have a low detection rate, limiting their potential use as clinically independent diagnostic features. Therefore, we aimed to engineer deep learning models to establish associations between ocular features and major hepatobiliary diseases and to advance automated screening and identification of hepatobiliary diseases from ocular images. Methods We did a multicentre, prospective study to develop models using slit-lamp or retinal fundus images from participants in three hepatobiliary departments and two medical examination centres. Included participants were older than 18 years and had complete clinical information; participants diagnosed with acute hepatobiliary diseases were excluded. We trained seven slit-lamp models and seven fundus models (with or without hepatobiliary disease [screening model] or one specific disease type within six categories [identifying model]) using a development dataset, and we tested the models with an external test dataset. Additionally, we did a visual explanation and occlusion test. Model performances were evaluated using the area under the receiver operating characteristic curve (AUROC), sensitivity, specificity, and F1* score. Findings Between Dec 16, 2018, and July 31, 2019, we collected data from 1252 participants (from the Department of Hepatobiliary Surgery of the Third Affiliated Hospital of Sun Yat-sen University, the Department of Infectious Diseases of the Affiliated Huadu Hospital of Southern Medical University, and the Nantian Medical Centre of Aikang Health Care [Guangzhou, China]) for the development dataset; between Aug 14, 2019, and Jan 31, 2020, we collected data from 537 participants (from the Department of Infectious Diseases of the Third Affiliated Hospital of Sun Yat-sen University and the Huanshidong Medical Centre of Aikang Health Care [Guangzhou, China]) for the test dataset. The AUROC for screening for hepatobiliary diseases of the slit-lamp model was 0·74 (95% CI 0·71–0·76), whereas that of the fundus model was 0·68 (0·65–0·71). For the identification of hepatobiliary diseases, the AUROCs were 0·93 (0·91–0·94; slit-lamp) and 0·84 (0·81–0·86; fundus) for liver cancer, 0·90 (0·88–0·91; slit-lamp) and 0·83 (0·81–0·86; fundus) for liver cirrhosis, and ranged 0·58–0·69 (0·55–0·71; slit-lamp) and 0·62–0·70 (0·58–0·73; fundus) for other hepatobiliary diseases, including chronic viral hepatitis, non-alcoholic fatty liver disease, cholelithiasis, and hepatic cyst. In addition to the conjunctiva and sclera, our deep learning model revealed that the structures of the iris and fundus also contributed to the classification. Interpretation Our study established qualitative associations between ocular features and major hepatobiliary diseases, providing a non-invasive, convenient, and complementary method for hepatobiliary disease screening and identification, which could be applied as an opportunistic screening tool. Funding Science and Technology Planning Projects of Guangdong Province; National Key RD Guangzhou Key Laboratory Project; National Natural Science Foundation of China.

Amorphous silicon (a-Si) is one of the most promising anode-materials for the lithium-ion battery owing to its large capacity and superior fracture resistance. However, a-Si is usually fabricated with the sophisticated chemical vapor deposition or pulse laser deposition in a limited scale. In this work, we have successfully prepared a-Si spheres (∼200 nm) by reducing the TiO2-coated silica spheres with Al powders in the molten salts at 300 °C. The coated TiO2 layer acts as a protective layer for structural maintenance during the reduction and a precursor for doping. The doped Ti element may suppress the crystal growth of Si to facilitate the formation of a-Si. The observation with in-situ transmission electron microscopy (TEM) further reveals that lithiation kinetics of the synthesized a-Si is controlled by the interfacial reaction. The Li+ diffusivity in a-Si determined from the observation is in the order of 10−14 cm2/s. The anode of a-Si spheres together with crystalline Si nanoparticles exhibits excellent electrochemical performance, delivering a reversible capacity of 1604 mAh/g at 4 A/g and a capacity retention of 78.3% after 500 cycles. The low temperature reduction process reported in this study provides a low-cost method to fabricate a-Si nanostructures as high-capacity durable anode materials

Dual-cooled annular fuel allows a significant increase in power density while maintaining or improving safety margins. However, the dual-cooled design brings much higher Zircaloy charge in reactor core, which could cause a great threaten of hydrogen explosion during severe accidents. Hence, an innovative fuel combined dual-cooled annular geometry and SiC cladding was proposed for the first time in this study. Capabilities of fuel design and behavior simulation were developed for this new fuel by the upgrade of FROBA-ANNULAR code. Considering characteristics of both SiC cladding and dual-cooled annular geometry, the basic fuel design was proposed and preliminary proved to be feasible. After that, a design optimization study was conducted, and the optimal values of as-fabricated plenum pressure and gas gap sizes were obtained. Finally, the performance simulation of the new fuel was carried out with the full consideration of realistic operation conditions. Results indicate that in addition to possessing advantages of both dual-cooled annular fuel and accident tolerant cladding at the same time, this innovative fuel could overcome the brittle failure issue of SiC induced by pellet-cladding interaction.

The Neolithic jades excavated from southern China often exhibit a serious corrosion phenomenon called “Whitening”, where the jade mineral aggregates have lost compact textures and transform into loose white powders, which cause a substantial decline in mechanical strength and the jades cannot remain intact. Meanwhile, a glossy hyaline layer with a more compact and uniform structure can be observed on the surface of some whitened jades, exert great influence in the integral structure strength of the jades and can be considered as highly significant natural reinforcing materials. The recent excavation of a workshop for jade processing in Zhejiang Province provided us with a great opportunity to investigate the deteriorated jades and the taphonomic environmental conditions associated with it. In this study, analyses of morphology and compositions revealed that the glassy layer is a composition of geopolymers with silica-alumina gels as the major components, which can also be found between mineral grains of jade crystals closest to the surface. Notably, some jade fragments with a yellowish infusion were found to be mechanically stronger compared to other jades unearthed from the same context, which may be explained by the consolidate effect of iron ions in the soil. These results have demonstrated the remarkable protective properties of soil colloids, and thus proposed that by using soil colloids as templates, consolidants with the natural compatibility with jades synthesized by chemical precipitations of charged inorganic colloidal particles can be a promising solution for jade conservation.

Infection patterns of avian haemosporidians result from the evolution of their associations with hosts, and can be shaped by multiple biotic factors. However, at the level of parasite species, few studies have investigated the details of the temporal dynamics of infection patterns in wild bird communities. We hereby studied a wild bird community in southern Sweden to investigate two generalist parasites (cyt b lineages PARUS1 and WW2) of the morphological species Haemoproteus majoris in their main host species (tits and warblers, respectively) to look for seasonal (spring to autumn) and age class related variation in infection patterns. For both lineages, we detected a similar temporal pattern in prevalence and infection intensity, with peak levels during the main nesting season in adults and a few weeks later in juveniles. Infections in juveniles were detected as soon as they started to be caught by mist nets, implying that they became infected when still in the nest or during the first weeks post-fledging. The initially high intensities in juveniles were followed by a significant decrease during the hatching year, emphasising the importance of studying haemosporidian infections in nestlings and fledglings. Both prevalence and infection intensity in adults increased from spring to early summer, either due to spring relapses or new infections. Both prevalence and infection intensity declined in adults at the time when independent juveniles of the respective species started to appear, suggesting that the rate of parasite withdrawal from blood exceeded the rates of new infections gained and relapses of previous infections. Prevalence in both juveniles and adults approached zero towards the end of the summer.

Non-damaging ultraviolet B (UV-B) light promotes photomorphogenic development and stress acclimation through UV-B-specific signal transduction in Arabidopsis. UV-B irradiation induces monomerization and nuclear translocation of the UV-B photoreceptor UV RESISTANCE LOCUS 8 (UVR8). However, it is not clear how the nuclear localization of UVR8 leads to changes in global gene expression. Here, we reveal that nuclear UVR8 governs UV-B-responsive transcriptional networks in concert with several previously known transcription factors, including ELONGATED HYPOCOTYL 5 (HY5) and PHYTOCHROME INTERACTING FACTOR 4 (PIF4). Based on the transcriptomic analysis, we identify MYB13 as a novel positive regulator in UV-B-induced cotyledon expansion and stress acclimation. MYB13 is UV-B inducible and is predominantly expressed in the cotyledons. Our results demonstrate that MYB13 protein functions as a transcription factor to regulate the expression of genes involved in auxin response and flavonoid biosynthesis through direct binding with their promoters. In addition, photoactivated UVR8 interacts with MYB13 in a UV-B-dependent manner and differentially modulates the affinity of MYB13 with its targets. Taken together, our results elucidate the cooperative function of the UV-B photoreceptor UVR8 with various transcription factors in the nucleus to orchestrate the expression of specific sets of downstream genes and, ultimately, mediate plant responses to UV-B light.

Summary: Background: The global dissemination of colistin resistance encoded by mcr-1 has been attributed to extensive use of colistin in livestock, threatening colistin efficacy in medicine. The emergence of mcr-1 in common pathogens, such as Escherichia coli, is of particular concern. China banned the use of colistin in animal feed from May 1, 2017. We investigated subsequent changes in mcr-1 prevalence in animals, humans, food, and the environment, and the genomic epidemiology of mcr-1-positive E coli (MCRPEC). Methods: Sampling was done before (October to December, 2016) and after (October to December, 2017, and 2018, respectively) the colistin ban. 3675 non-duplicate pig faecal samples were collected from 14 provinces (66 farms) in China to measure intervention-related changes in mcr-1 prevalence. 15 193 samples were collected from pigs, healthy human volunteers, patients colonised or infected with Enterobacteriaceae who were admitted to hospital, food and the environment in Guangzhou, to characterise source-specific mcr-1 prevalence and the wider ecological effect of the ban. From these samples, 688 MCRPEC were analysed with whole genome sequencing, plasmid conjugation, and S1 pulsed-field gel electrophoresis with Southern blots to characterise associated genomic changes. Findings: After the ban, mcr-1 prevalence decreased significantly in national pig farms, from 308 (45%) of 684 samples in 2016 to 274 (19%) of 1416 samples in 2018 (p

Methicillin-resistant Staphylococcus aureus (MRSA) poses a serious threat to global public health due to its resistance to specific antibiotics. Bacteriophages particularly the lytic ones are promoted as a potential powerful-tool to combat infections caused by drug resistant bacteria; while several disadvantages limited the application of the temperate ones. In this study, we isolated 14 phages against MRSA strains, and found three ones showed the capacity of killing most of the target MRSA strains. However, whole genome sequencing and generation of lysogens indicated that these three bacteriophage candidates were temperate ones. Therefore, we mutated one (4PHSA25) of them to a virulent bacteriophage (4PHCISA25). Phenotypical characterization assays revealed that 4PHCISA25 had similar lytic spectrum, temperature, pH, and UV sensitivities to 4PHSA25. However, 4PHCISA25 displayed increased lytic activities and decreased bacteriophage insensitive mutant frequency. Biofilm removing assays showed that 4PHCISA25 exhibited a better capacity than 4PHSA25 on eliminating biofilms formed by MRSA strains. Mouse experiments demonstrated that injection of 4PHCISA25 was safe to the mice and treatment with it (10

The plant UV-B photoreceptor UV RESISTANCE LOCUS 8 (UVR8) exists as a homodimer in its inactive ground state. Upon UV-B exposure, UVR8 monomerizes and interacts with a downstream key regulator, the CONSTITUTIVE PHOTOMORPHOGENIC 1/SUPPRESSOR OF PHYA (COP1/SPA) E3 ubiquitin ligase complex, to initiate UV-B signaling. Two WD40 proteins, REPRESSOR OF UV-B PHOTOMORPHOGENESIS 1 (RUP1) and RUP2 directly interact with monomeric UVR8 and facilitate UVR8 ground state reversion, completing the UVR8 photocycle. Here, we reconstituted the RUP-mediated UVR8 redimerization process in vitro and reported the structure of the RUP2-UVR8

To expand crop planting areas, reestablishment of crop latitude adaptation based on genetic variation in photoperiodic genes can be performed, but it is quite time consuming. By contrast, a crop variety that already exhibits multi-latitude adaptation has the potential to increase its planting areas to be more widely and quickly available. However, the importance and potential of multi-latitude adaptation of crop varieties have not been systematically described. Here, combining daylength-sensing data with the cropping system of elite rice and maize varieties, we found that varieties with gradual daylength sensing coupled with optimum cropping modes have an enhanced capacity for multi-latitude adaptation in China. Furthermore, this multi-latitude adaptation expanded their planting areas and indirectly improved China's nationwide rice and maize unit yield. Thus, coupling the daylength-sensing process with optimum cropping modes to enhance latitude adaptability of excellent varieties represents an exciting approach for deploying crop varieties with the potential to expand their planting areas and quickly improve nationwide crop unit yield in developing countries.