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1.
J Virol ; 98(10): e0049724, 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39345142

RESUMO

Duck circovirus (DuCV) is widely recognized as a prominent virus in China's duck farming industry, known for its ability to cause persistent infections and significant immunosuppression, which can lead to an increased susceptibility to secondary infections, posing a significant threat to the duck industry. Moreover, clinical evidence also indicates the potential vertical transmission of the virus through duck embryos to subsequent generations of ducklings. However, the limited availability of suitable cell lines for in vitro cultivation of DuCV has hindered further investigation into the molecular mechanisms underlying its infection and pathogenicity. In this study, we observed that oral DuCV infection in female breeding ducks can lead to oviduct, ovarian, and follicular infections. Subsequently, the infection can be transmitted to the fertilized eggs, resulting in the emergence of virus-carrying ducklings upon hatching. In contrast, the reproductive organs of male breeding ducks were unaffected by the virus, thus confirming that vertical transmission of DuCV primarily occurs through infection in female breeding ducks. By analyzing transcriptome sequencing data from the oviduct, we focused on claudin-2, a gene encoding the tight junction protein CLDN2 located on the cell membrane, which showed significantly increased expression in DuCV-infected oviducts of female breeding ducks. Notably, CLDN2 was confirmed to interact with the unique structural protein of DuCV, namely capsid protein (Cap), through a series of experimental approaches including co-immunoprecipitation (co-IP), GST pull-down, immunofluorescence, and adhesion-blocking assays. Furthermore, we demonstrated that the Cap protein binds to the extracellular loop structural domains EL1 and EL2 of CLDN2. Subsequently, by constructing a series of truncated bodies of the CLDN2 promoter region, we identified the transcription factor SP5 for CLDN2. Moreover, we found that DuCV infection triggers the activation of the MAPK-ERK signaling pathway in DEF cells and ducks, leading to an upregulation of SP5 and CLDN2 expression. This process ultimately leads to the transportation of mature CLDN2 to the cell surface, thereby facilitating increased virus adherence to the target organs. In conclusion, we discovered that DuCV utilizes host CLDN2 proteins to enhance adhesion and infection in oviducts and other target organs. Furthermore, we elucidated the signaling pathways involved in the interaction between DuCV Cap proteins and CLDN2, which provides valuable insights into the molecular mechanism underlying DuCV's infection and vertical transmission. IMPORTANCE: Although duck circovirus (DuCV) poses a widespread infection and a serious hazard to the duck industry, the molecular mechanisms underlying DuCV infection and transmission remain elusive. We initially demonstrated vertical transmission of DuCV through female breeding ducks by simulating natural infection. Furthermore, a differentially expressed membrane protein CLDN2 was identified on the DuCV-infected oviduct of female ducks, and its extracellular loop structural domains EL1 and EL2 were identified as the interaction sites of DuCV Cap proteins. Moreover, the binding of DuCV Cap to CLDN2 triggered the intracellular MAPK-ERK pathway and activated the downstream transcription factor SP5. Importantly, we demonstrated that intracellular Cap also interacts with SP5, leading to upregulation of CLDN2 transcription and facilitating enhanced adherence of DuCV to target tissue, thereby promoting viral infection and transmission. Our study sheds light on the molecular mechanisms underlying vertical transmission of DuCV, highlighting CLDN2 as a promising target for drug development against DuCV infection.


Assuntos
Infecções por Circoviridae , Circovirus , Claudinas , Patos , Sistema de Sinalização das MAP Quinases , Doenças das Aves Domésticas , Animais , Patos/virologia , Feminino , Doenças das Aves Domésticas/virologia , Doenças das Aves Domésticas/transmissão , Doenças das Aves Domésticas/metabolismo , Circovirus/genética , Infecções por Circoviridae/virologia , Infecções por Circoviridae/veterinária , Infecções por Circoviridae/transmissão , Infecções por Circoviridae/metabolismo , Claudinas/metabolismo , Claudinas/genética , Masculino , Ligação Viral , Transmissão Vertical de Doenças Infecciosas/veterinária
2.
Microb Pathog ; 186: 106489, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38061666

RESUMO

Trichinellosis caused by Trichinella spiralis (T. spiralis) is a zoonotic disease that poses a substantial risk to human health. At present, vaccines used to prevent trichinellosis are effective, but the production of antibody levels and immunogenicity are low. Adjuvants can increase antibody levels and vaccine immunogenicity. As a result, it is critical to develop an effective adjuvant for the T. spiralis vaccine. Recent research has shown that traditional Chinese medicine polysaccharides with low-toxicity and biodegradability can act as adjuvants in vaccines. In this study, BALB/c mice were orally inoculated with a recombinant Lactobacillus plantarum (L. plantarum) vaccine expressing the T. spiralis cathepsin F-like protease 1 gene (rTs-CPF1), which was given three times at 10-day intervals. Lycium barbarum polysaccharide (LBP) was administered orally for 37 days. At 37 days after the first immunization, mice were infected with 350 T. spiralis muscle larvae (ML). Specific IgG and sIgA antibody levels against the T. spiralis CPF1 protein were increased in mice immunized with rTs-CPF1+LBP compared to those immunized with rTs-CPF1 alone. Furthermore, LBP increased IFN-γ and IL-4 expression levels, and the number of intestinal and intramuscular worms was significantly reduced in the rTs-CPF1+LBP group compared to that in the rTs-CPF1 group. In the rTs-CPF1+LBP group, the reduction rates of adult worms and muscle larvae were 47.31 % and 68.88 %, respectively. To summarize, LBP promotes the immunoprotective effects of the T. spiralis vaccine and may be considered as a novel adjuvant in parasitic vaccines.


Assuntos
Lactobacillus plantarum , Trichinella spiralis , Triquinelose , Camundongos , Humanos , Animais , Trichinella spiralis/genética , Triquinelose/prevenção & controle , Triquinelose/parasitologia , Catepsina F , Lactobacillus plantarum/genética , Antígenos de Helmintos/genética , Vacinas Sintéticas , Adjuvantes Imunológicos/farmacologia , Camundongos Endogâmicos BALB C
3.
Artigo em Inglês | MEDLINE | ID: mdl-38518140

RESUMO

Objective: The efficacy of selective malposition ligation combined with hemorrhoid and fistula I prescription and the improvement of complications were assessed to improve surgical efficiency and safety. Methods: 423 patients undergoing complex mixed hemorrhoid surgery at different time points were included as research objects and enrolled into group A (malposition ligation), group B (selective malposition ligation), and group C (selective malposition ligation and hemorrhoid and fistula I), each with 141 cases. Results: The scores for visual analogue scale (VAS), edema, and hemorrhage of group C 8h, 1 day, 2 days, 3 days, 5 days, and 7 days after surgery were all inferior to those in groups A and B, while that of group B was inferior to that in group A (P < .05). The duration of wound healing of group C (15.33 ± 2.78 days) was shorter than that of groups A (21.78 ± 3.22 days) and B (18.34 ± 3.01 days), and this duration of group B was shorter than that of group A (P < .05). The total effective rate of group C (96.45%) was superior to that of groups B (96.45%) and A (82.27%). The total effective rate of group B was superior to that of group A. The falling-off rate of the rubber ring in groups C and B was inferior to that in group A. The incidence of total complications in group C (9.93%) was inferior to that in groups B (30.50%) and A (30.50%), while that of group B was inferior to that in group A (P < .05). Conclusion: After selective malposition ligation, the oral intake of hemorrhoid and fistula I could promote the recovery of wounds among patients with complex mixed hemorrhoids and reduce the incidence of postoperative hemorrhage and edema. Hence, it has significant clinical application values.

4.
Sensors (Basel) ; 24(5)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38474987

RESUMO

We present an innovative approach to mitigating brightness variations in the unmanned aerial vehicle (UAV)-based 3D reconstruction of tidal flat environments, emphasizing industrial applications. Our work focuses on enhancing the accuracy and efficiency of neural radiance fields (NeRF) for 3D scene synthesis. We introduce a novel luminance correction technique to address challenging illumination conditions, employing a convolutional neural network (CNN) for image enhancement in cases of overexposure and underexposure. Additionally, we propose a hash encoding method to optimize the spatial position encoding efficiency of NeRF. The efficacy of our method is validated using diverse datasets, including a custom tidal flat dataset and the Mip-NeRF 360 dataset, demonstrating superior performance across various lighting scenarios.

5.
J Environ Manage ; 366: 121652, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38971069

RESUMO

Regions can meet their development demands through trade, with the attendant environmental costs being shifted to other regions, and carbon emissions emitted from different industries could be transferred over long distances through the increasingly diversified trade network. However, it remains unclear how regional trade leads to the tele-connection and transfer of embodied carbon emissions form industries, and what is the structure and characteristics of the transfer. Thus, multiregional input‒output models and complex network analysis are employed to reveal the tele-connection of carbon emissions from industries in China. The results show that embodied carbon emissions from trade increased by 869.47 million tons during in five years, with North China being the largest outflow area, while the coastal regions being the inflow areas. Moreover, the secondary industry is the highest source of embodied carbon emissions, accounting for 96.68 % of the volume, and the transfer of carbon emissions mainly occurs in North and East China. In carbon emissions networks, North China holds a controlling position, as analysed by degree and strength. The first 23.3%-30% of nodes carry about 62.6%-72.4% of the entire carbon emissions flow, and the network conforms to scale-free features. Centrality further reveals that northern and coastal areas occupy core positions, with interregional carbon flows dominating the critical pathways in the network. The number of clusters evolved from three to four communities during 2012-2017 in the network, demonstrating that the carbon flow network is developing towards multipolarity and modularity. This study underscores the urgency of mitigating carbon emissions in industrial trade by identifying key nodes and cluster structures in emission networks.


Assuntos
Carbono , Indústrias , China , Comércio , Monitoramento Ambiental
6.
Nurs Crit Care ; 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38945698

RESUMO

BACKGROUND: Very and extremely preterm infants (VEPIs) experience sensory deprivation in the neonatal intensive care unit (NICU). While various sensory-supported interventions might improve immediate physiological response, their impact on long-term development remains unclear. Additionally, these interventions may pose challenges in the NICU environment due to complex treatments and monitoring requirements. AIMS: This review aimed to understand the current evidence on sensory-supported interventions in the NICU, identify the components of these interventions and determine their effects on the VEPIs. STUDY DESIGN: A systematic search across nine electronic databases (PubMed, EBSCO, EMBASE, Web of Science, Scopus, Cochrane, Cochrane trial, IEEE Xplore DL and ACM DL) was conducted in December 2020 and updated in September 2022. The search gathers information on sensory-supported interventions for VEPIs in the NICU. RESULTS: The search yielded 23 systematic reviews and 22 interventional studies, categorized into auditory (19), tactile/kinesthetic (5), positional/movement support (7), visual (1) and multisensory (13) interventions. While unimodal and multimodal interventions showed short-term benefits, their long-term effects on VEPIs are indeterminate. Translating these findings into clinical practice remains a challenge due to identified gaps. CONCLUSION: Our reviews indicate that sensory-supported interventions have a transient impact, with intervention studies reporting positive effects. Future research should develop and test comprehensive, continuous multisensory interventions tailored for the early NICU stage. RELEVANCE TO CLINICAL PRACTICE: Multimodal sensory interventions show promise for VEPIs, but long-term effects need further study. Standardizing protocols for NICU integration and parental involvement is crucial. Ongoing research and collaboration are essential for optimizing interventions and personalized care.

7.
Infect Immun ; 91(4): e0038222, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-36939354

RESUMO

Trichinellosis is an important foodborne zoonosis, and no effective treatments are yet available. Nod-like receptor (NLR) plays a critical role in the host response against nematodes. Therefore, we aimed to explore the role of the NLRP3 inflammasome (NLRP3) during the adult, migrating, and encysted stages of Trichinella spiralis infection. The mice were treated with the specific NLRP3 inhibitor MCC950 after inoculation with T. spiralis. Then, the role that NLRP3 plays during T. spiralis infection of mice was evaluated using enzyme-linked immunosorbent assay (ELISA), Western blotting, flow cytometry, histopathological evaluation, bone marrow-derived macrophage (BMDM) stimulation, and immunofluorescence. The in vivo results showed that NLRP3 enhanced the Th1 immune response in the adult and migrating stages and weakened the Th2 immune response in the encysted stage. NLRP3 promoted the release of proinflammatory factors (interferon gamma [IFN-γ]) and suppressed the release of anti-inflammatory factors (interleukin 4 [IL-4]). Pathological changes were also improved in the absence of NLRP3 in mice during T. spiralis infection. Importantly, a significant reduction in adult worm burden and muscle larvae burden at 7 and 35 days postinfection was observed in mice treated with the specific NLRP3 inhibitor MCC950. In vitro, we first demonstrated that NLRP3 in macrophages can be activated by T. spiralis proteins and promotes IL-1ß and IL-18 release. This study revealed that NLRP3 is involved in the host response to T. spiralis infection and that targeted inhibition of NLRP3 enhanced the Th2 response and accelerated T. spiralis expulsion. These findings may help in the development of protocols for controlling trichinellosis.


Assuntos
Trichinella spiralis , Triquinelose , Camundongos , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR , Antígenos de Helmintos , Camundongos Endogâmicos BALB C
8.
J Am Chem Soc ; 145(39): 21679-21686, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37747934

RESUMO

The charge transport through supramolecular junctions exhibits unique quantum interference (QI) effects, which provide an opportunity for the design of supramolecular transistors. Benefiting from the configuration dependence of QI, configuration control of the supramolecular assemblies to demonstrate the QI features is a key but challenging step. In this work, we fabricated the supramolecular transistors and investigated the charge transport through the conducting channel of the individual π-stacked thiophene/phenylene co-oligomers (TPCOs) using the electrochemically gated scanning tunneling microscope break junction technique. We controlled the configuration of the supramolecular channel and switched the QI features between the anti-resonance and resonance states of the supramolecular channels. We observed the supramolecular transistor with its on/off ratio above 103 (∼1300), a high gating efficiency of ∼165 mV/dec, a low off-state leakage current of ∼30 pA, and the channel length scaled down to <2.0 nm. Density functional theory calculations suggested that the QI features in π-stacked TPCOs vary depending on the supramolecular architecture and can be manipulated efficiently by fine-tuning the supramolecular configurations. This work reveals the potential of the supramolecular channels for molecular electronics and provides a fundamental understanding of intermolecular charge transport.

9.
Environ Sci Technol ; 57(40): 15255-15265, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37768274

RESUMO

Numerous studies have emphasized the toxicity of graphene-based nanomaterials to algae, however, the fundamental behavior and processes of graphene in biological hosts, including its transportation, metabolization, and bioavailability, are still not well understood. As photosynthetic organisms, algae are key contributors to carbon fixation and may play an important role in the fate of graphene. This study investigated the biological fate of 14C-labeled few-layer graphene (14C-FLG) in Chlamydomonas reinhardtii (C. reinhardtii). The results showed that 14C-FLG was taken up by C. reinhardtii and then translocated into its chloroplast. Metabolomic analysis revealed that 14C-FLG altered the metabolic profiles (including sugar metabolism, fatty acid, and tricarboxylic acid cycle) of C. reinhardtii, which promoted the photosynthesis of C. reinhardtii and then enhanced their growth. More importantly, the internalized 14C-FLG was metabolized into 14CO2, which was then used to participate in the metabolic processes required for life. Approximately 61.63%, 25.31%, and 13.06% of the total radioactivity (from 14CO2) was detected in carbohydrates, lipids, and proteins of algae, respectively. Overall, these results reveal the role of algae in the fate of graphene and highlight the potential of available graphene in bringing biological effects to algae, which helps to better assess the environmental risks of graphene.

10.
Sensors (Basel) ; 23(20)2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37896748

RESUMO

In this paper, we propose a robust and integrated visual odometry framework exploiting the optical flow and feature point method that achieves faster pose estimate and considerable accuracy and robustness during the odometry process. Our method utilizes optical flow tracking to accelerate the feature point matching process. In the odometry, two visual odometry methods are used: global feature point method and local feature point method. When there is good optical flow tracking and enough key points optical flow tracking matching is successful, the local feature point method utilizes prior information from the optical flow to estimate relative pose transformation information. In cases where there is poor optical flow tracking and only a small number of key points successfully match, the feature point method with a filtering mechanism is used for posing estimation. By coupling and correlating the two aforementioned methods, this visual odometry greatly accelerates the computation time for relative pose estimation. It reduces the computation time of relative pose estimation to 40% of that of the ORB_SLAM3 front-end odometry, while ensuring that it is not too different from the ORB_SLAM3 front-end odometry in terms of accuracy and robustness. The effectiveness of this method was validated and analyzed using the EUROC dataset within the ORB_SLAM3 open-source framework. The experimental results serve as supporting evidence for the efficacy of the proposed approach.

11.
Environ Sci Technol ; 56(24): 17663-17673, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36456188

RESUMO

Understanding how nanomaterials interact with cell membranes has important implications for ecotoxicology and human health. Here, we investigated the interactions between graphitic carbon nitride (g-C3N4, CN) and red blood cells, a plausible contact target for nanoparticles when they enter the bloodstream. Through a hemolysis assay, the cytotoxicity of CN derived from different precursors was quantitatively assessed, which is highly related to the surface area of CN. Reactive oxygen species (ROS) generation and lipid peroxidation detection confirmed that CN causes rapid cell membrane rupture by a physical interaction mechanism rather than ROS-related chemical oxidation. Dye leakage assay and theoretical simulation indicated that the less-layered CN is prone to folding inward to wrap and extract lipid molecules from cell membranes. The electron-rich inherent pores of CN play a dominant role in capturing the headgroups of phospholipids, whereas the hydrophobic interaction is critical for the anchoring of lipid tails. Our further experimental evidence demonstrated that the destructive extraction of phospholipids from cell membranes by CN occurs primarily in the outer leaflet, and phosphatidylcholine is the most easily extracted lipid. Moreover, the formation of protein corona on CN was found to decrease the nonspecific interactions but increase steric repulsion, thus mitigating CN cytotoxicity. Overall, our data provide a molecular basis for CN's cytotoxicity.


Assuntos
Bicamadas Lipídicas , Fosfolipídeos , Humanos , Bicamadas Lipídicas/análise , Fosfolipídeos/análise , Espécies Reativas de Oxigênio/análise , Membrana Celular
12.
Environ Sci Technol ; 56(13): 9435-9445, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35700278

RESUMO

Numerous studies on the bioavailability of graphene-based nanomaterials relate to the water-only exposure route. However, the sediment exposure route should be the most important pathway for benthic organisms to ingest graphene, while to date little work on the bioavailability of graphene in benthic organisms has been explored. In this study, with the help of carbon-14-labeled few-layer graphene (14C-FLG), we quantificationally compared the bioaccumulation, biodistribution, and elimination kinetics of 14C-FLG in loaches via waterborne and sediment exposures. After 72 h of exposure, the accumulated 14C-FLG in loaches exposed via waterborne was 14.28 µg/g (dry mass), which was 3.18 times higher than that (4.49 µg/g) exposed via sediment. The biodistribution results showed that, compared to waterborne exposure, sediment exposure remarkably facilitated the transport of 14C-FLG from the gut into the liver, which made it difficult to be excreted. Although 14C-FLG did not cause significant hepatotoxicity, the disruption of intestinal microbiota homeostasis, immune response, and several key metabolic pathways in the gut were observed, which may be due to the majority of 14C-FLG being accumulated in the gut. Overall, this study reveals the different bioavailabilities of graphene in loaches via waterborne and sediment exposures, which is helpful in predicting its bioaccumulation capability and trophic transfer ability.


Assuntos
Cipriniformes , Grafite , Poluentes Químicos da Água , Animais , Disponibilidade Biológica , Radioisótopos de Carbono , Cipriniformes/metabolismo , Sedimentos Geológicos , Distribuição Tecidual , Poluentes Químicos da Água/metabolismo
13.
J Opt Soc Am A Opt Image Sci Vis ; 39(9): 1712-1722, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36215639

RESUMO

Discriminative correlation filter (DCF) based methods have recently been widely used for visual tracking tasks. The adaptive spatiotemporal-regulation based tracker (AutoTrack) can only partially solve some limitations of the DCF framework including filter degradation and the boundary effect, but its application scenarios need to be broadened, and performance improvements are also required. To further surmount these difficulties, this paper provides an object-awareness-module based mutation detection dual correlation filter (MDDCF-OAM). The main innovation points of this work are: (1) an object-mask based context enhancer is proposed to formulate a more robust appearance model; (2) a dual filter training-learning structure is adopted to allow the dual filters to restrict each other and suppress the filter degradation effect; (3) a Gaussian label map is updated with the refined joint response map to detect and attenuate the response mutation effects. Exhaustive experiments have been conducted to test the efficiency of the suggested MDDCF-OAM on four benchmarks, namely, OTB2015, UAV123, TC128, and VOT2019. The results indicate that: (1) the introduced MDDCF-OAM surpasses nine state-of-the-art trackers; (2) the MDDCF-OAM has a real-time speed of 32 frames per second, which is sufficient for target tracking tasks in numerous scenarios, especially unmanned aerial vehicles and camera tracking.

14.
Sensors (Basel) ; 22(20)2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36298226

RESUMO

OBJECTIVE: The shallow underwater environment is complex, with problems of color shift, uneven illumination, blurring, and distortion in the imaging process. These scenes are very unfavorable for the reasoning of the detection network. Additionally, typical object identification algorithms struggle to maintain high resilience in underwater environments due to picture domain offset, making underwater object detection problematic. METHODS: This paper proposes a single-stage detection method with the double enhancement of anchor boxes and features. The feature context relevance is improved by proposing a composite-connected backbone network. The receptive field enhancement module is introduced to enhance the multi-scale detection capability. Finally, a prediction refinement strategy is proposed, which refines the anchor frame and features through two regressions, solves the problem of feature anchor frame misalignment, and improves the detection performance of the single-stage underwater algorithm. RESULTS: We achieved an effect of 80.2 mAP on the Labeled Fish in the Wild dataset, which saves some computational resources and time while still improving accuracy. On the original basis, UWNet can achieve 2.1 AP accuracy improvement due to the powerful feature extraction function and the critical role of multi-scale functional modules. At an input resolution of 300 × 300, UWNet can provide an accuracy of 32.4 AP. When choosing the number of prediction layers, the accuracy of the four and six prediction layer structures is compared. The experiments show that on the Labeled Fish in the Wild dataset, the six prediction layers are better than the four. CONCLUSION: The single-stage underwater detection model UWNet proposed in this research has a double anchor frame and feature optimization. By adding three functional modules, the underwater detection of the single-stage detector is enhanced to address the issue that it is simple to miss detection while detecting small underwater targets.


Assuntos
Algoritmos , Peixes , Animais
15.
Angew Chem Int Ed Engl ; 61(40): e202210097, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-35981229

RESUMO

The Fano resonance in single-molecule junctions could be created by interaction with discrete and continuous molecular orbitals and enables effective electron transport modulation between constructive and destructive interference within a small energy range. However, direct observation of Fano resonance remains unexplored because of the disappearance of discrete orbitals by molecule-electrode coupling. We demonstrated the room-temperature observation of Fano resonance from electrochemical gated single-molecule conductance and current-voltage measurements of a para-carbazole anion junction. Theoretical calculations reveal that the negative charge on the nitrogen atom induces a localized HOMO on the molecular center, creating Fano resonance by interfering with the delocalized LUMO on the molecular backbone. Our findings demonstrate that the Fano resonance in electron transport through single-molecule junctions opens pathways for designs of interference-based electronic devices.

16.
Plant Dis ; 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441011

RESUMO

Chongqing coptis (Coptis chinensis Franchet) industry produces more than 60% of the Chinese coptis crop, and has been exported to many countries and regions. Since 2008, root rot has become a serious and widespread disease on coptis plants in Shizhu county with an average incidence of 40%, and yield losses up to 67%. Symptomatic coptis plants showed stunted growth, with the fibrous roots and main roots having brown or black, rotten, necrotic lesions. To our knowledge, Fusarium solani, F. carminascens, F. oxysporum and F. tricinctum have been previously reported as pathogens of coptis root rot (Luo et al. 2014; Cheng et al. 2020; Wu et al. 2020), but non Fusarium pathogens has not been reported yet. In order to identify new pathogens, 33 diseased roots were collected from Shizhu (30°18'N, 108°30'E) in October 2019. Small samples (0.5 cm in length) were cut from the border between diseased and healthy tissue, and then put on PDA after surface sterilization. Cultures were incubated at 25°C in dark until fungal colonies were observed. After subculturing for 3 times, 3 out of 21 isolates yielded a similar type of fungal colony. White, aerial, fluffy mycelium were formed and reached 8.3 cm diameter within 7 days, and dark pigmentation developed in the centre. Colonies turned to gray with age, and abundant dark brown pycnidia and black stromata were formed at maturity. Alpha conidia were aseptate, hyaline, fusiform to ellipsoidal, often biguttulate, measuring (6.0-8.5)×(2.0-3.0) µm. Beta conidia were aseptate, hyaline, linear to hooked, measuring (18-30)×(1.0-1.5) µm (Figure S1). For further identification, a multigene phylogenetic analysis was carried out. The internal transcribed spacer (ITS), translation elongation factor 1ɑ (tef1-ɑ), histone H3 (his3), calmodulin (cal), and ß-tubulin (tub2) gene regions were amplified with ITS1/ITS4, EF1-728F/EF1-986R, CYLH3F/H3-1b, CAL228F/CAL737R, T1/Bt2b (White et al. 1990; Glass and Donaldson 1995; Carbone and Kohn 1999; Crous et al. 2004). GenBank accession numbers of isolate H13 were MT463391 for the ITS region, MT975573 for tef1-ɑ, MT975574 for his3, MT975575 for cal, and MT975576 for tub2. BLAST results showed the ITS, tef1-ɑ, his3, cal and tub2 sequences revealed 99.82% (553/554 base pairs), 100% (347/347 base pairs), 100% (474/474 base pairs), 99.39% (486/489 base pairs), and 99.14% (803/810 base pairs) homology respectively with those of Diaporthe eres (MN816416.1, KU557616.1, KC343564.1, KU557595.1, and KY569366.1). Thus, H13 were identified as D. eres based on its morphological and molecular characteristics. Pathogenicity of D. eres in coptis was investigated using the H13 isolate (1 of the 3 isolates). The roots of 10 healthy 2-year-old coptis plants were individually inoculated with 5 ml of a 106 conidia/mL conidial suspension and sterilized water was used to mock inoculate. Thirty days after inoculation, most of the inoculated coptis roots showed dark brown and rotten root, similar to those observed in the field, whereas mock inoculated roots showed healthy. D. eres was recovered from symptomatic roots and identified based on morphology. To our knowledge, this is the first report of D. eres causing root rot of coptis not only in China but anywhere in the world.

17.
Sensors (Basel) ; 21(13)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206979

RESUMO

With the growth of computing power, deep learning methods have recently been widely used in machine fault diagnosis. In order to realize highly efficient diagnosis accuracy, people need to know the detailed health condition of collected signals from equipment. However, in the actual situation, it is costly and time-consuming to close down machines and inspect components. This seriously impedes the practical application of data-driven diagnosis. In comparison, the full-labeled machine signals from test rigs or online datasets can be achieved easily, which is helpful for the diagnosis of real equipment. Thus, we introduced an improved Wasserstein distance-based transfer learning method (WDA), which learns transferable features between labeled and unlabeled signals from different forms of equipment. In WDA, Wasserstein distance with cosine similarity is applied to narrow the gap between signals collected from different machines. Meanwhile, we use the Kuhn-Munkres algorithm to calculate the Wasserstein distance. In order to further verify the proposed method, we developed a set of case studies, including two different mechanical parts, five transfer scenarios, and eight transfer learning fault diagnosis experiments. WDA reached an average accuracy of 93.72% in bearing fault diagnosis and 84.84% in ball screw fault diagnosis, which greatly surpasses state-of-the-art transfer learning fault diagnosis methods. In addition, comprehensive analysis and feature visualization are also presented.


Assuntos
Algoritmos , Redes Neurais de Computação , Humanos , Aprendizado de Máquina
18.
Opt Express ; 28(24): 36389-36402, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33379733

RESUMO

This paper proposes a novel power-efficient light-emitting diode (LED) placement algorithm for indoor visible light communication (VLC). In the considered model, the LEDs can be designedly placed for high power efficiency while satisfying the indoor communication and illumination requirements. This design problem is formulated as a power minimization problem under both communication and illumination level constraints. Due to the interactions among LEDs and the illumination uniformity constraint, the formulated problem is complex and non-convex. To solve the problem, we first transform the complex uniformity constraint into a series of linear constraints. Then an iterative algorithm is proposed to decouple the interactions among LEDs and transforms the original problem into a series of convex sub-problems. Then, we use Lagrange dual method to solve the sub-problem and obtain a convergent solution of the original problem. Simulation results show that the proposed LED placement algorithm can harvest 14% power consumption gain when compared with the baseline scheme with centrally placed LEDs.

19.
Antonie Van Leeuwenhoek ; 113(9): 1263-1278, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32564275

RESUMO

Plant growth-promoting rhizobacteria are a group of free-living bacteria that colonize plant rhizosphere and benefit plant root growth, thereby increasing host plant to cope with salinity induced stress. The aim of this study was to (1) isolate and characterize auxin-producing bacteria showing a high plant growth-promoting (PGP) potential, and (2) evaluate the PGP effects on the growth of Medicago sativa L under salinity stress (130 mM NaCl). Of thirteen isolates, Bacillus megaterium NRCB001 (NRCB001), B. subtilis subsp. subtilis NRCB002 (NRCB002) and B. subtilis NRCB003 (NRCB003) had the ability to produce auxin, which ranged from 47.53 to 154.38 µg ml-1. The three auxin-producing bacterial strains were shown multiple PGP traits, such as producing siderophore and NH3, showing ACC deaminase activity, solubilize phosphate and potassium. Furthermore, NRCB001, NRCB002, and NRCB003 could survive in LB medium containing 1750 mM NaCl. The three auxin-producing with salinity tolerance strains were selected for further analyses. In greenhouse experiments, when inoculated with NRCB001, NRCB002 and NRCB003, dry weight of alfalfa significantly (P < 0.05) increased by 24.1%, 23.1% and 38.5% respectively, compared with those of non-inoculated control seedlings under normal growth condition. When inoculated with NRCB002 and NRCB003, dry weight of alfalfa significantly (P < 0.05) increased by 96.9 and 71.6% respectively, compared with those of non-inoculated control seedlings under 130 mM NaCl condition. Our results indicated that NRCB002 and NRCB003 having PGP traits are promising candidate strains to develop biofertilizers, especially used under salinity stress conditions.


Assuntos
Bacillus megaterium/fisiologia , Bacillus subtilis/fisiologia , Ácidos Indolacéticos/metabolismo , Medicago sativa/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Salinidade , Bacillus megaterium/classificação , Bacillus megaterium/isolamento & purificação , Bacillus subtilis/classificação , Bacillus subtilis/isolamento & purificação , DNA Bacteriano/genética , Medicago sativa/microbiologia , Filogenia , Desenvolvimento Vegetal , RNA Ribossômico 16S/genética , Rizosfera , Cloreto de Sódio , Microbiologia do Solo
20.
Plant Dis ; 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32915116

RESUMO

Coptis chinensis Franchet, is a perennial herb used as a traditional Chinese medicine. Annual production of Coptis is about 3000 tons in Shizhu, Chongqing. In recent years, root rot has become a serious and widespread disease on Coptis in Shizhu with an average incidence of 40%, and yield losses up to 67%. Infected plants were easy to pull from the soil, and most of the fibrous roots and main roots were brown or black compared to healthy roots that were yellow. Severely infected plants were wilted and necrotic. In October 2019, 33 diseased roots were collected from Shizhu (30°18'N, 108°30'E), and small samples (0.5 cm in length) were cut from the border between diseased and healthy tissue, successively sterilized with 75% ethanol and 2% sodium hypochlorite, rinsed 3 times with sterilized water, dried on sterilized filter paper, and transferred onto PDA, and incubated at 25°C for 7 days in dark. Eighteen distinct fungal isolates (H1-H18) were isolated and Koch's postulates were conducted to verify the pathogenicity of individual isolates. The rhizosphere soil of healthy 2-year-old Coptis plants was inoculated by pouring 5 mL of conidial suspension (106 conidia/mL) scraped from a culture of each isolate on PDA. Sterilized water was used to mock inoculate. For each isolate, 6 plants were inoculated. After 20 days, the roots of all plants inoculated with H15 or H18 were dark brown and rotten, while mock inoculated plants were healthy. The isolates H15 and H18 were re-isolated from symptomatic plants. Isolate H15 formed abundant white mycelium on PDA and produced rose pigment in the agar. Conidia were long and slender, straight to slightly curved, with 1-3 septate. The apical cells were tapering and bent, and the foot cells were distinctly notched. Conidiogenous cells were monophialides and polyphialides. No chlamydospores were observed (Figure S1). Isolate H18 formed white sparse mycelium on PDA and produced no pigment in the agar. Conidia were relatively wide, straight and stout, with 3-5 septate. The apical cells were blunt and rounded, and the foot cells were barely notched. Conidiogenous cells were long monophialides. Chlamydospores were formed intercalary in the hyphae (Figure S2). For further identification, the internal transcribed spacer (ITS), ß-tubulin, translation elongation factor 1ɑ (EF1ɑ) and RNA polymerase second largest subunit (RPB2) gene regions were amplified with ITS1/ITS4, Bt2a/Bt2b, EF1/EF2 and 5f2/7cr (White et al. 1990; Glass and Donaldson, 1995; O'Donnell et al. 2010). GenBank accession numbers of H15 and H18 were MT463390 and MT463389 for the ITS region, MT465656 and MT465654 for ß-tubulin, MT653321 and MT465651 for EF1ɑ, and MT653323 and MT653322 for RPB2. BLAST results showed the ITS, ß-tubulin, EF1ɑ, and RPB2 sequences revealed 100% (533/533 base pairs), 100% (265/265 base pairs), 98% (622/632 base pairs), and 99% (936/947 base pairs) homology respectively with those of Fusarium avenaceum (MN186746.1, MH791368.1, KU238140.1, and MK185027.1), and 100% (537/537 base pairs), 100% (227/227 base pairs), 100% (688/688 base pairs), and 99.03% (918/927 base pairs) with F. solani in GenBank (MH857319.1, MN692929.1, KP674211.1, and MH300549.1), respectively. Thus, H15 and H18 were identified as F. avenaceum and F. solani based on its morphological and molecular characteristics. To our knowledge, F. solani has been previously reported as a pathogen on Coptis (Luo et al. 2014), and this is the first report of root rot on Coptis caused by F. avenaceum in the world. Identification of the pathogens is important for effective disease management and control.

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