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Image quality assessment (IQA) based on deep learning faces the overfitting problem due to limited training samples available in existing IQA databases. Transfer learning is a plausible solution to the problem, in which the shared features derived from the large-scale Imagenet source domain could be transferred from the original recognition task to the intended IQA task. However, the Imagenet source domain and the IQA target domain as well as their corresponding tasks are not directly related. In this paper, we propose a new transitive transfer learning method for no-reference image quality assessment (TTL-IQA). First, the architecture of the multi-domain transitive transfer learning for IQA is developed to transfer the Imagenet source domain to the auxiliary domain, and then to the IQA target domain. Second, the auxiliary domain and the auxiliary task are constructed by a new generative adversarial network based on distortion translation (DT-GAN). Furthermore, a TTL network of the semantic features transfer (SFTnet) is proposed to optimize the shared features for the TTL-IQA. Experiments are conducted to evaluate the performance of the proposed method on various IQA databases, including the LIVE, TID2013, CSIQ, LIVE multiply distorted and LIVE challenge. The results show that the proposed method significantly outperforms the state-of-the-art methods. In addition, our proposed method demonstrates a strong generalization ability.

Van der Waals solids with tunable band gaps and interfacial properties have been regarded as a class of promising active materials for electrocatalytic hydrogen evolution reaction (HER). However, due to the anisotropic features, their basal planes are usually electrochemically inert, only a few unsaturated edge atoms could serve as active centers to actuate H2 generation. Hence, material utilization and productivity efficiency are insufficient for practical applications. Recently, diverse defects have been confirmed to enable tailoring atomic configurations and electronic properties of van der Waals solids, thus triggering their superior catalytic activity of in-plane atoms while introducing high amount of new active sites. In this minireview, we summarize the state-of-the-art progress of defect engineering in van der Waals solids for HER, focusing in particular on their advantages in material modification and corresponding catalytic mechanisms. We also propose the challenges and perspectives of these catalytic materials in terms of both experimental synthesis and fundamental understanding of the defect structures.

MYB transcription factors play important roles in plant responses to cold stress, but the associated underlying mechanisms remain unclear. In this study, a cold-induced MYB transcription factor, DgMYB2, was isolated from chrysanthemum (Chrysanthemum morifolium Ramat). DgMYB2 was localized to the nucleus and exhibited transactivational activity. Overexpression of DgMYB2 improved cold tolerance in chrysanthemum, while cold tolerance in the antisense suppression lines decreased compared to that of the wild type. Additionally, electrophoretic mobility shift assays, chromatin immunoprecipitation, luciferase complementary imaging analysis, and dual-luciferase reporter gene detection experiments confirmed that DgMYB2 directly targets DgGPX1 and increases the activity of glutathione peroxidase to reduce the accumulation of reactive oxygen species, thereby improving cold resistance in chrysanthemum.

The bZIP transcription factor plays a very important role in abiotic stresses, e.g. drought, salt, and low-temperature stress, but the mechanism of action at low temperature is still unclear. In this study, overexpression of DgbZIP3 led to increased tolerance of chrysanthemum (Chrysanthemum morifolium Ramat.) to cold stress, whereas antisense suppression of DgbZIP3 resulted in decreased tolerance. Electrophoretic mobility shift assay (EMSA), chromatin immunoprecipitation (ChIP), luciferase complementary imaging analysis (LCI), and dual-luciferase reporter gene detection (DLA) experiments indicated that DgbZIP3 directly bound to the promoter of DgPOD and activated its expression. DgbZIP2 was identified as a DgbZIP3-interacting protein using yeast two-hybrid, co-immunoprecipitation, LCI, and bimolecular fluorescence complementation assays. Overexpression of DgbZIP2 led to increased tolerance of chrysanthemum to cold stress, whereas antisense suppression of DgbZIP2 resulted in decreased tolerance. A ChIP–qPCR experiment showed that DgbZIP2 was highly enriched in the promoter of DgPOD, while DLA, EMSA, and LCI experiments further showed that DgbZIP2 could not directly regulate the expression of DgPOD. The above results show that DgbZIP3 interacts with DgbZIP2 to regulate the expression of DgPOD to promote an increase in peroxidase activity, thereby regulating the balance of reactive oxygen species and improving the tolerance of chrysanthemum to low-temperature stress.

Arbuscular mycorrhizal symbiosis (AMS) is widespread mutualistic association between plants and fungi, which plays an essential role in nutrient exchange, enhancement in plant stress resistance, development of host, and ecosystem sustainability. Previous studies have shown that plant small secreted proteins (SSPs) are involved in beneficial symbiotic interactions. However, the role of SSPs in the evolution of AMS has not been well studied yet. In this study, we performed computational analysis of SSPs in 60 plant species and identified three AMS-specific ortholog groups containing SSPs only from at least 30% of the AMS species in this study and three AMS-preferential ortholog groups containing SSPs from both AMS and non-AMS species, with AMS species containing significantly more SSPs than non-AMS species. We found that independent lineages of monocot and eudicot plants contained genes in the AMS-specific ortholog groups and had significant expansion in the AMS-preferential ortholog groups. Also, two AMS-preferential ortholog groups showed convergent changes, between monocot and eudicot species, in gene expression in response to arbuscular mycorrhizal fungus Rhizophagus irregularis. Furthermore, conserved cis-elements were identified in the promoter regions of the genes showing convergent gene expression. We found that the SSPs, and their closely related homologs, in each of three AMS-preferential ortholog groups, had some local variations in the protein structural alignment. We also identified genes co-expressed with the Populus trichocarpa SSP genes in the AMS-preferential ortholog groups. This first plant kingdom-wide analysis on SSP provides insights on plant-AMS convergent evolution with specific SSP gene expression and local diversification of protein structures.

Predicting the polyproline type II (PPII) helix structure is crucial important in many research areas, such as the protein folding mechanisms, the drug targets, and the protein functions. However, many existing PPII helix prediction algorithms encode the protein sequence information in a single way, which causes the insufficient learning of protein sequence feature information. To improve the protein sequence encoding performance, this paper proposes a BERT-based PPII helix structure prediction algorithm (BERT-PPII), which learns the protein sequence information based on the BERT model. The BERT model’s CLS vector can fairly fuse sample’s each amino acid residue information. Thus, we utilize the CLS vector as the global feature to represent the sample’s global contextual information. As the interactions among the protein chains’ local amino acid residues have an important influence on the formation of PPII helix, we utilize the CNN to extract local amino acid residues’ features which can further enhance the information expression of protein sequence samples. In this paper, we fuse the CLS vectors with CNN local features to improve the performance of predicting PPII structure. Compared to the state-of-the-art PPIIPRED method, the experimental results on the unbalanced dataset show that the proposed method improves the accuracy value by 1% on the strict dataset and 2% on the less strict dataset. Correspondingly, the results on the balanced dataset show that the AUCs of the proposed method are 0.826 on the strict dataset and 0.785 on less strict datasets, respectively. For the independent test set, the proposed method has the AUC value of 0.827 on the strict dataset and 0.783 on the less strict dataset. The above experimental results have proved that the proposed BERT-PPII method can achieve a superior performance of predicting the PPII helix.

There is currently a lack of sufficient data on human papillomavirus (HPV)-attributable cervical carcinoma in China. Accordingly, we aimed to determine the prevalence and genotype distribution of HPV among women with cervical lesions in Shenzhen, in order to evaluate the potential benefit of HPV vaccination programs and inform cervical cancer control policies. We enrolled 5,255 patients who were admitted to the University of Chinese Academy of Sciences Shenzhen Hospital from January 2017 to December 2019. The HPV prevalence and genotype distribution were analyzed using the 21 HPV GenoArray diagnostic assay. A total of 937/5,255 patients showed HPV-positivity (prevalence rate 17.83%), of whom 85.81% (804/937) had high-risk HPV infection. HPV52 was the most prevalent genotype (4.72%, 248/5,255), followed by HPV58 (3.04%, 160/5,255), and HPV16 (2.72%, 143/5,255). The HPV prevalence rates among women with a normal cervix, low-grade intraepithelial lesions, high-grade intraepithelial lesions, invasive cervical cancer, and other characteristics were 15.63% (50/320), 58.65% (61/104), 80.00% (44/55), 88.57% (31/35), and 15.84% (751/4,741), respectively. HPV16, HPV18, and HPV52 accounted for the majority of cervical lesions, and the infection rates of HPV16 and HPV18 gradually increased with intraepithelial lesion progression (both P

3D direct planimetry is increasingly used in clinical practice as a rapid way to measure the mitral valve area (MVA) in patients with rheumatic mitral stenosis (MS) who underwent three-dimensional transesophageal echocardiography (3D-TEE). However, data on its accuracy and reliability are scarce. This study aimed to compare the MVA measurements obtained by 3D direct planimetry to the conventional technique multiplanar reconstruction (MPR) in MS patients using 3D-TEE. We retrospectively included 49 patients with rheumatic MS undergoing clinically-indicated 3D-TEE in the study. We determined the 3D direct planimetry measurements of MVA from the left atria aspect (MVALA) and the left ventricle aspect (MVALV), and compared those with the MPR method (MVAMPR). We also assessed the major and minor diameters of the mitral valve orifice using MPR and 3D direct planimetry. We found an excellent agreement between the MVA measurements obtained by the MPR method and 3D direct planimetry (MVALA and MVALV) [intraclass correlation coefficients (ICC) = 0.951 and 0.950, respectively]. However, the MVAMPR measurements were significantly larger than the MVALA and MVALV (p

The steady increase in the prevalence of multidrug-resistant Staphylococcus aureus has made the search for novel antibiotics to combat this clinically important pathogen an urgent matter. In an effort to discover antibacterials with new chemical structures and mechanisms, we performed a growth inhibition screen of a synthetic library against S. aureus and discovered a promising scaffold with a 1,3,5-oxadiazin-2-one core. These compounds are potent against both methicillin-sensitive and methicillin-resistant S. aureus strains. Isolation of compound-resistant strains followed by whole genome sequencing revealed its cellular target as FabH, a key enzyme in bacterial fatty acid synthesis. Detailed mechanism of action studies suggested the compounds inhibit FabH activity by covalently modifying its active site cysteine residue with high selectivity. A crystal structure of FabH protein modified by a selected compound Oxa1 further confirmed covalency and suggested a possible mechanism for reaction. Moreover, the structural snapshot provided an explanation for compound selectivity. On the basis of the structure, we designed and synthesized Oxa1 derivatives and evaluated their antibacterial activity. The structure-activity relationship supports the hypothesis that noncovalent recognition between compounds and FabH is critical for the activity of these covalent inhibitors. We believe further optimization of the current scaffold could lead to an antibacterial with potential to treat drug-resistant bacteria in the clinic.

Separation of dyes and proteins from water remains a significant challenge. Common absorbents without recyclability might bring secondary pollutions, which may be avoided by developing stimuli-responsive smart absorbents. Here in this work, a CO2-responsive polymer poly(2-(dimethylamino) ethyl methacrylate) was grafted from cellulose fibers (Cell-g-PDEA). The chemical structure and surface morphology were confirmed with nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray powder diffraction and scanning electron microscope. The CO2-sensitivity was demonstrated by monitoring the pH, surface Zeta potential and dispersed appearance under stimulus of CO2. Furthermore, the modified cellulose fibers were packed into a syringe to construct a smart separation column that reversibly captured and released anionic dyes and proteins from water under gas stimulus. Comparing with traditional pH or temperature responsive materials, the CO2-responsive cellulose fibers take the advantages on energy-saving, good reversibility and moderate running conditions, thus might find applications in smart separations, clinical diagnose and therapies.

Error or drift is frequently produced in pose estimation based on geometric "feature detection and tracking" monocular visual odometry(VO) when the speed of camera movement exceeds 1.5m/s. While, in most VO methods based on deep learning, weight factors are in the form of fixed values, which are easy to lead to overfitting. A new measurement system, for monocular visual odometry, named Deep Learning Visual Odometry(DLVO), is proposed based on neural network. In this system, Convolutional Neural Network(CNN) is used to extract feature and perform feature matching. Moreover, Recurrent Neural Network(RNN) is used for sequence modeling to estimate camera's 6-dof poses. Instead of fixed weight values of CNN, Bayesian distribution of weight factors are introduced in order to effectively solve the problem of network over-fitting. The 18,726 frame images in KITTI dataset are used for training network. This system can increase the generalization ability of network model in prediction process. Compared with original Recurrent Convolutional Neural Network(RCNN), our method can reduce the loss of test model by 5.33%. And it's an effective method in improving the robustness of translation and rotation information than traditional VO methods.

Vibrio parahaemolyticus is an important pathogenic bacterium in both food safety management and mariculture. Rapid and accurate detection technologies are critical for effective control of its outbreak and spreading. Conventional technologies and polymerase chain reaction (PCR)-based approaches have limited usage because of the requirement of laboratory instruments and trained personnel. Using the isothermal recombinase polymerase amplification (RPA) technology, several detection assays have been developed with added convenience. Combining the lateral flow strip (LFS) test with RPA can further simplify the detection. In this study, an improved RPA assay using LFS for visual detection of V. parahaemolyticus was developed. Primers were designed targeting the virulence genes and screened for amplification efficiency, nonspecific amplification, and primer-dimer formation. Probes were designed for the best primer pairs, and the weakness of LFS tests, being easily affected by primer-dependent artifacts, was overcome by sequence modifications on primers and probe. The RPA-LFS assay took 25 min at 35 to 45 °C, and showed excellent specificity. It detected as low as one colony forming unit (CFU) of V. parahaemolyticus per reaction without DNA purification, or 10 CFU/10 g spiked food samples with 2 hr of enrichment. The detection limit was better than the currently available RPA-based detection methods. Application of the RPA-LFS assay for simulated samples or real clinical samples showed accurate and consistent detection results compared to bioassay and quantitative PCR. The RPA-LFS assay provided a rapid, accurate, and convenient V. parahaemolyticus detection method suitable for on-site detection in resource-limited conditions. PRACTICAL APPLICATION: This research developed a rapid and visual detection technology for Vibrio parahaemolyticus that is not dependent on complicated equipment. The detection process takes 25 min and the result is read with the naked eye. A detection kit can be developed based on this technology for on-site detection of V. parahaemolyticus in resource-limited regions for food safety management and mariculture.

Multifunctional nanoparticles for imaging and treatment in cancer are getting more and more attentions recently. Herein, halloysite nanotubes (HNTs), natural clay nanotubes, are designed as multifu...

Background Hand, foot, and mouth disease (HFMD) is a common infectious disease occurring in children under 5 years of age worldwide, and Enterovirus A71 (EV-A71) and Coxsackievirus A16 (CVA-16) are identified as the predominant pathogens. In recent years, Coxsackievirus A6 (CVA-6) and Coxsackievirus A10 (CVA-10) have played more and more important role in a series of HFMD outbreaks. This study aimed to understand the epidemic characteristics associated with HFMD outbreak in Guangzhou, 2018. Methods The clinical and laboratory data of 1220 enterovirus-associated HFMD patients in 2018 were analysed in this study. Molecular diagnostic methods were performed to identify its serotypes. Phylogenetic analyses were depicted based on the complete VP1 gene. Results There were 21 enterovirus serotypes detected in Guangzhou in 2018. Three serotypes of enterovirus, CVA-6 (364/1220, 29.8%), CVA-10 (305/1220, 25.0%), and CVA-16 (397/1220, 32.5%), were identified as the causative pathogens and accounted for 87.3% among all 1220 HFMD patients. In different seasons, CVA-6 was the predominant pathogen of HFMD during autumn, and CVA-10 as well as CVA-16 were more prevalent in summer. Patients infected by CVA-6, CVA-10 or CVA-16 showed similar clinical features and laboratory characteristics, and the ratios of severe HFMD were 5.8, 5.9, and 1.5% in the three serotypes. Phylogenetic analyses of VP1 sequences showed that the CVA-6, CVA-10, and CVA-16 sequences belonged to the sub-genogroup E2, genogroup E, and genogroup B1, respectively. Conclusions CVA-6, CVA-10, and CVA-16 were the predominant and co-circulated serotypes in Guangzhou China, 2018, which should be the new target for prevention and control of HFMD. Our findings provide useful information for diagnosis, treatment, and prevention of HFMD.

The worm-like micropatterns were elaborated by drying halloysite clay nanotube dispersions placed between two horizontal glass slides. This 0.1-0.2 mm thick confined space induces the fractal self-...

Organic–inorganic metal halide perovskites have achieved great success in applications such as light-emitting diodes, photodetectors (PDs) and solar cells due to their high light absorption coefficients, tunable band gaps and simple solution-process technologies. However, their polycrystalline films have low carrier mobility and high defect states, which limit the device performance. As substitutes, perovskite microcrystal (MC) films exhibit higher carrier mobility and lower defect state density and thus, they have received much attention in recent years. Herein, we introduce MAPbX3 (X = Br, I) MC films with controllable thickness and adjustable band gap, and the self-powered MAPbI3 perovskite MC PDs (MCPDs) with a structure of ITO glass/perovskite MC film/carbon have been assembled for the first time. By optimizing the thickness of the MC film, our hole-transport-layer-free (HTL-free) PDs exhibit excellent self-powered performance, with an on/off ratio as high as 2 × 105, the rise/fall time of 80/580 μs, the responsivity of 0.26 A W−1, the detectivity of 7.01 × 1011 Jones and the linear dynamic range of 107 dB. In addition, our MCPDs without encapsulation show excellent light and storage stability. These results indicate a good method for preparing high-performance and high-stability perovskite MC devices.

This manuscript has been authored by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan).

Nanozymes are nanomaterials with enzyme-like activities, which have been developed for inflammatory disease therapy by reactive oxygen species (ROS) scavenging. The application of nanozymes in ulcerative colitis (UC) treatment not only inherits the merits of small molecular antioxidants (

Background: Strong evidence of the correlation between age-related macular degeneration (AMD) and vitreomacular interface abnormality (VMIA). Meanwhile, as a crucial mechanism of retinal pigment epithelial (RPE) cells’ homeostasis, autophagy induction by cyclic stretch appears to be particularly significant.Methods: Cultured ARPE-19 cells were subjected to cyclic stretch (20% elongation, 1HZ) for 1h, 2h, 6h, 12h,24h and 48h by FX-5000 Tension System. Then, we observed the expression levels of LC3I, LC3II, Beclin-1, SQSTM1/p62, LAMP-1, mTOR and phosphorylated mTOR(pmTOR), AMPK and pAMPK, NADPH oxidase 4 (NOX4), and vascular endothelial growth factor (VEGF) in RPE cells under stretch by western blot and immunofluorescence.Results: We found autophagic proteins mostly induced by cyclic stretch in a time-dependent fashion via mTOR suppression and AMPK activation, except for SQSTM1/p62. 3-Methyladenine(3-MA), an inhibitor for autophagy, could reduce the up-regulation of autophagy due to cyclic stretch, leading to higher level of VEGF release after 24h cyclic stretch. Rapamycin could narrow the increase degree of VEGF and NOX4 by cyclic stretch by raise autophagic level in RPE cells.Conclusion: Stretch might induce autophagy in RPE cells by mTOR or AMPK pathway. Autophagy might play the protective function for RPE cells away from mechanical stress derived from VMIA-related AMD.

CRISPR/Cas has recently emerged as the most reliable system for genome engineering in various species. However, concerns about risks associated with the CRISPR/Cas technology are increasing on potential unintended DNA changes that might accidentally arise from CRISPR gene editing. Developing a system that can detect and report the presence of active CRISPR/Cas tools in biological systems is therefore very necessary. Here, we developed four real-time detection systems that can spontaneously indicate the presence of active CRISPR-Cas tools for genome editing and gene regulation including CRISPR/Cas9 nuclease, base editing, prime editing, and CRISPRa in plants. Using the fluorescence-based molecular biosensors, we demonstrated that the activities of CRISPR/Cas9 nuclease, base editing, prime editing, and CRISPRa can be effectively detected in transient expression via protoplast transformation and leaf infiltration (in

As satellite observation technology rapidly develops, the number of remote sensing (RS) images dramatically increases, and this leads RS image retrieval tasks to be more challenging in terms of speed and accuracy. Recently, an increasing number of researchers have turned their attention to this issue, as well as hashing algorithms, which map real-valued data onto a low-dimensional Hamming space and have been widely utilized to respond quickly to large-scale RS image search tasks. However, most existing hashing algorithms only emphasize preserving point-wise or pair-wise similarity, which may lead to an inferior approximate nearest neighbor (ANN) search result. To fix this problem, we propose a novel triplet ordinal cross entropy hashing (TOCEH). In TOCEH, to enhance the ability of preserving the ranking orders in different spaces, we establish a tensor graph representing the Euclidean triplet ordinal relationship among RS images and minimize the cross entropy between the probability distribution of the established Euclidean similarity graph and that of the Hamming triplet ordinal relation with the given binary code. During the training process, to avoid the non-deterministic polynomial (NP) hard problem, we utilize a continuous function instead of the discrete encoding process. Furthermore, we design a quantization objective function based on the principle of preserving triplet ordinal relation to minimize the loss caused by the continuous relaxation procedure. The comparative RS image retrieval experiments are conducted on three publicly available datasets, including UC Merced Land Use Dataset (UCMD), SAT-4 and SAT-6. The experimental results show that the proposed TOCEH algorithm outperforms many existing hashing algorithms in RS image retrieval tasks.

Genital Chlamydia trachomatis (CT) is one of the most common agents of sexually transmitted infections and can cause severe disorders. This study aimed to analyse the genetic and clinical characteristics of genital CT infection among women in Guangzhou, China.From September 2020 to August 2021, a total of 8955 female patients were enrolled in this study. The presence of genital CT was detected by real-time PCR, and 273 positive samples were randomly selected for further genetic and clinical characteristics analysis.The positive rate of genital CT infection was 7.5% (670/8955), with the highest rate in women aged 21-30 years. A total of 8 genotypes were identified: DH, J, K, and recombinant genotype Ba/D. The predominant genotype was J (n = 78, 28.6%), followed by E (n = 63, 23.1%), F (n = 48, 17.6%), and D (n = 38, 13.9%). Abnormal vaginal discharge (n = 165, 61.8%), cervical columnar epithelial ectopy (n = 124, 46.4%), vaginal itching (n = 77, 28.8%), and lower abdominal pain (n = 61, 22.8%) were the predominant symptoms. Additionally, genotype G infection exhibited a significantly higher rate of abnormal vaginal discharge (P = 0.03) and genotype D infection exhibited a higher white blood cell count (P = 0.01) than the other genotypes. Phylogenetic analysis revealed a total of 20 variants with 25 mutation positions and the H2 variant in four patients was first discovered in our study.Genotypes J, E, F, and D were the major genotypes of genital CT in Guangzhou, and they manifested as abnormal vaginal discharge, cervical columnar epithelial ectopy, vaginal itching, and lower abdominal pain. The present study provides guidance for future integrated interventions to reduce the burden of genital CT infection and accelerate the development of vaccines.

Tumor genome methylation is closely related to tumor immunosuppression. In the present study, we evaluated the fluctuations in DNA methylation levels, and the numbers of infiltrating T cells and their cytokines in different-grade cervical lesions. A total of 154 human cervical specimens that included LSIL (43 cases), HSIL (48 cases), and cervical squamous cancer (63 cases) were used for this study. Immunohistochemistry for 5-hydroxymethylcytosine (5hmC) and T-cell-attracting chemokines was performed, and multiplex immunofluorescence labeling was used to identify different T-cell subtypes. We found that the proportions of samples that immunostained weakly or negatively for 5hmC were increased commensurately with elevations in the severity of cervical lesions. The expression of T-cell-attracting chemokines—including CXCL9, CXCL10, and CXCL11—was positively associated with 5hmC levels, and CXCL9 was the cytokine that was most pronounced. With the progression of cervical lesions, the numbers of total T cells, CTL, and NK cells in the cervical tissues all gradually decreased. During the occurrence and development of cervical squamous carcinoma, 5hmC was gradually lost, and immunosuppression occurred in precancerous cervical lesions.

Virus-assisted delivery of the clustered regularly interspaced short palindromic (CRISPR)/CRISPR-associated (Cas) system represents a promising approach for editing plant genomes. However, the relatively large size of the CRISPR/Cas9 system is challenging to package into viral vectors with confined packaging capacity. To address this technical challenge, we developed a strategy that splits the required CRISPR-Cas9 components across a dual-vector system in which CRISPR-Cas reassembles into an active form following co-infection to achieve targeted genome editing in plant cells. An intein-mediated split system was adapted and optimized in plant cells by successfully demonstrating split-eYGFPuv expression. Using a plant-based biosensor, we demonstrated for the first time that the split-SpnCas9 is capable of inducing efficient base editing in plant cells and identified several valid split sites for future biodesign strategies. Overall, this strategy provides new opportunities to bridge different CRISPR/Cas9 tools including base editor, prime editor, and CRISPR activation with virus-mediated gene editing.

In this study, the triangle interpolation method for the calculation of mapping functions of plates containing an opening with arbitrary shapes is investigated with an improved method for point adjudgment during iterations. Afterwards, four kinds of openings with typical shapes are considered and the mapping functions for them are calculated, based on which the influence of calculation parameters such as iteration time and the number of terms on the accuracy of mapping function is discussed. Finally, the stress around an inverted U-shaped opening and around an arched opening under different far-field stress conditions is calculated and the effect of opening shape and lateral pressure coefficient on stress distribution and rock mechanical behaviors is further analyzed combined with the discrete element method (DEM) numerical simulation. The result shows that the stability and failure pattern of the rock mass is correlated with the stress around the opening, which is affected by the opening shape. The existence of opening also greatly reduces the enhancing influence of confining stress on rock specimen.

Woody biomass is an important feedstock for biofuel production. Manipulation of wood properties that enable efficient conversion of biomass to biofuel reduces cost of biofuel production. Wood cell wall composition is regulated at several levels that involve expression of transcription factors such as wood-/secondary cell wall-associated NAC domains (WND or SND). InArabidopsis thaliana, SND1regulates cell wall composition through activation of its down-stream targets such as MYBs. The functional aspects ofSND1homologs in the woodyPopulushave been studied through transgenic manipulation. In this study, we investigated the role ofPdWND1B, Populus SND1sequence ortholog, in wood formation using transgenic manipulation through over-expression or silencing under the control of a vascular-specific4-coumarate-CoAligase (4CL) promoter. As compared to control plants,PdWND1B-RNAi plants were shorter in height, with significantly reduced stem diameter and dry biomass, whereas there were no significant differences in growth and productivity ofPdWND1Bover-expression plants. Conversely,PdWND1Bover-expression lines showed a significant reduction in cellulose and increase in lignin content, whereas there was no significant impact on lignin content of down-regulated lines. Stem carbohydrate composition analysis revealed a decrease in glucose, mannose, arabinose, and galactose, but an increase in xylose in the over-expression lines. Transcriptome analysis revealed upregulation of several downstream transcription factors and secondary cell wall related structural genes in thePdWND1Bover-expression lines that corresponded to significant phenotypic changes in cell wall chemistry observed inPdWND1Boverexpression lines. Relative to the control, glucose release and ethanol production from stem biomass was significantly reduced in over-expression lines but appeared enhanced in the RNAi lines. Our results show thatPdWND1Bis an important factor determining biomass productivity, cell wall chemistry and its conversion to biofuels inPopulus.

Woody biomass is an important feedstock for biofuel production. Manipulation of wood properties that enable efficient conversion of biomass to biofuel reduces cost of biofuel production. Wood cell wall composition is regulated at several levels that involve expression of transcription factors such as wood-/secondary cell wall-associated NAC domains (WND or SND). In

In order to overcome the sluggish kinetics of the redox conversion between Fe

The circadian clock drives time-specific gene expression, allowing for associated biological processes to be active during certain times of the 24 h day. Crassulacean acid metabolism (CAM) photosynthetic plants represent an interesting case of circadian regulation of gene expression as CO2 fixation and stomatal movement in CAM plants display strong circadian dynamics. The molecular mechanisms behind how the circadian clock enabled these physiological differences is not well understood. Therefore, we set out to investigate whether core circadian elements in CAM plants were re-phased during evolution, or whether networks of phase-specific genes were simply connected to different core elements. We utilized a new metric for identifying candidate core genes of a periodic gene network and then applied the Local Edge Machine (LEM) algorithm to infer regulatory relationships between the candidate core clock genes and orthologs of known core clock genes in K. fedtschenkoi. We also used LEM to identify stomata-related gene targets for K. fedtschenkoi core clock genes and constructed a subsequent gene regulatory network. Our results provide new insights into the mechanism of circadian control of CAM-related genes in K. fedtschenkoi, facilitating the engineering of CAM machinery into non-CAM plants for sustainable crop production in water-limited environments.

The catechol group of dopamine (DA) can chelate with the metal ion in the crystal of molecular organic frameworks (MOFs). Based on this principle, a magnetic metal polydopamine (PDA) framework (Fe

The energy-induced peroxydisulfate (PDS) activation is a green and effective approach for pollutant degradation, while the huge energy consumption would significantly increase the cost of wastewater treatment. In this study, by taking carbon nanotubes (CNTs) membrane as the light to heat (LTH) conversion materials, we developed a photothermal PDS activation process for degradation of organic contaminants in a flow-by reactor, with hydroxyl radicals (

Precise modification of plant genomes, such as seamless insertion, deletion, or replacement of DNA sequences at a predefined site, is a challenging task. Gene targeting (GT) and prime editing are currently the best approaches for this purpose. However, these techniques are inefficient in plants, which limits their applications for crop breeding programs. Recently, substantial developments have been made to improve the efficiency of these techniques in plants. Several strategies, such as RNA donor templating, chemically modified donor DNA template, and tandem-repeat homology-directed repair, are aimed at improving GT. Additionally, improved prime editing gRNA design, use of engineered reverse transcriptase enzymes, and splitting prime editing components have improved the efficacy of prime editing in plants. These emerging strategies and existing technologies are reviewed along with various perspectives on their future improvement and the development of robust precision genome editing technologies for plants.

Dysregulation of lipid metabolism could lead to the development of metabolic disorders. We report here that the F-box protein JFK promotes excessive lipid accumulation in adipose tissue and contributes to the development of metabolic syndrome. JFK transgenic mice develop spontaneous obesity, accompanied by dyslipidemia, hyperglycemia, and insulin resistance, phenotypes that are further exacerbated under high-fat diets. In contrast, Jfk knockout mice are lean and resistant to diet-induced metabolic malfunctions. Liver-specific reconstitution of JFK expression in Jfk knockout mice leads to hepatic lipid accumulation resembling human hepatic steatosis and nonalcoholic fatty liver disease. We show that JFK interacts with and destabilizes ING5 through assembly of the SCF complex. Integrative transcriptomic and genomic analysis reveals that the SCFJFK -ING5 axis interferes with AMPK activity and fatty acid β-oxidation, leading to the suppression of hepatic lipid catabolism. Significantly, JFK is upregulated and AMPKα1 is down-regulated in liver tissues from NAFLD patients. These results reveal that SCFJFK is a bona fide E3 ligase for ING5 and link the SCFJFK -ING5 axis to the development of obesity and metabolic syndrome.

Small secreted proteins (SSPs) are less than 250 amino acids in length and are actively transported out of cells through conventional protein secretion pathways or unconventional protein secretion pathways. In plants, SSPs have been found to play important roles in various processes, including plant growth and development, plant response to abiotic and biotic stresses, and beneficial plant–microbe interactions. Over the past 10 years, substantial progress has been made in the identification and functional characterization of SSPs in several plant species relevant to agriculture, bioenergy, and horticulture. Yet, there are potentially a lot of SSPs that have not been discovered in plant genomes, which is largely due to limitations of existing computational algorithms. Recent advances in genomics, transcriptomics, and proteomics research, as well as the development of new computational algorithms based on machine learning, provide unprecedented capabilities for genome-wide discovery of novel SSPs in plants. In this review, we summarize known SSPs and their functions in various plant species. Then we provide an update on the computational and experimental approaches that can be used to discover new SSPs. Finally, we discuss strategies for elucidating the biological functions of SSPs in plants.