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Despite experimental and observational studies demonstrating that biodiversity enhances primary productivity, the best metric for predicting productivity at broad geographic extents-functional trait diversity, phylogenetic diversity, or species richness-remains unknown. Using >1.8 million tree measurements from across eastern US forests, we quantified relationships among functional trait diversity, phylogenetic diversity, species richness, and productivity. Surprisingly, functional trait and phylogenetic diversity explained little variation in productivity that could not be explained by tree species richness. This result was consistent across the entire eastern United States, within ecoprovinces, and within data subsets that controlled for biomass or stand age. Metrics of functional trait and phylogenetic diversity that were independent of species richness were negatively correlated with productivity. This last result suggests that processes that determine species sorting and packing are likely important for the relationships between productivity and biodiversity. This result also demonstrates the potential confusion that can arise when interdependencies among different diversity metrics are ignored. Our findings show the value of species richness as a predictive tool and highlight gaps in knowledge about linkages between functional diversity and ecosystem functioning.
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Biodiversidade , Florestas , Biomassa , Ecossistema , Filogenia , Estados UnidosRESUMO
Influenza D virus (IDV) utilizes bovines as a primary reservoir with periodical spillover to other hosts. We have previously demonstrated that IDV binds both 9-O-acetylated N-acetylneuraminic acid (Neu5,9Ac2) and 9-O-acetylated N-glycolylneuraminic acid (Neu5Gc9Ac). Bovines produce both Neu5,9Ac2 and Neu5Gc9Ac, while humans are genetically unable to synthesize Neu5Gc9Ac. 9-O-Acetylation of sialic acids is catalyzed by CASD1 via a covalent acetyl-enzyme intermediate. To characterize the role of Neu5,9Ac2 and Neu5Gc9Ac in IDV infection and determine which form of 9-O-acetylated sialic acids drives IDV entry, we took advantage of a CASD1 knockout (KO) MDCK cell line and carried out feeding experiments using synthetic 9-O-acetyl sialic acids in combination with the single-round and multi-round IDV infection assays. The data from our studies show that (i) CASD1 KO cells are resistant to IDV infection and lack of IDV binding to the cell surface is responsible for the failure of IDV replication; (ii) feeding CASD1 KO cells with Neu5,9Ac2 or Neu5Gc9Ac resulted in a dose-dependent rescue of IDV infectivity; and (iii) diverse IDVs replicated robustly in CASD1 KO cells fed with either Neu5,9Ac2 or Neu5Gc9Ac at a level similar to that in wild-type cells with a functional CASD1. These data demonstrate that IDV can utilize Neu5,9Ac2- or non-human Neu5Gc9Ac-containing glycan receptor for infection. Our findings provide evidence that IDV has acquired the ability to infect and transmit among agricultural animals that are enriched in Neu5Gc9Ac, in addition to posing a zoonotic risk to humans expressing only Neu5,9Ac2.IMPORTANCEInfluenza D virus (IDV) has emerged as a multiple-species-infecting pathogen with bovines as a primary reservoir. Little is known about the functional receptor that drives IDV entry and promotes its cross-species spillover potential among different hosts. Here, we demonstrated that IDV binds exclusively to 9-O-acetylated N-acetylneuraminic acid (Neu5,9Ac2) and non-human 9-O-acetylated N-glycolylneuraminic acid (Neu5Gc9Ac) and utilizes both for entry and infection. This ability in effective engagement of both 9-O-acetylated sialic acids as functional receptors for infection provides an evolutionary advantage to IDV for expanding its host range. This finding also indicates that IDV has the potential to emerge in humans because Neu5,9Ac2 is ubiquitously expressed in human tissues, including lung. Thus, results of our study highlight a need for continued surveillance of IDV in humans, as well as for further investigation of its biology and cross-species transmission mechanism.
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Deltainfluenzavirus , Ácidos Neuramínicos , Receptores Virais , Animais , Bovinos , Membrana Celular/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Ácidos Neuramínicos/metabolismo , Orthomyxoviridae/metabolismo , Receptores Virais/metabolismo , Ácidos Siálicos/metabolismoRESUMO
In the present study, the debatable prognostic value of Ki67 in patients with non-small cell lung cancer (NSCLC) was attributed to the heterogeneity between lung adenocarcinoma (LUAD) and lung squamous carcinoma (LUSC). Based on meta-analyses of 29 studies, a retrospective immunohistochemical cohort of 1479 patients from our center, eight transcriptional datasets and a single-cell datasets with 40 patients, we found that high Ki67 expression suggests a poor outcome in LUAD, but conversely, low Ki67 expression indicates worse prognosis in LUSC. Furthermore, low proliferation in LUSC is associated with higher metastatic capacity, which is related to the stronger epithelial-mesenchymal transition potential, immunosuppressive microenvironment and angiogenesis. Finally, nomogram model incorporating clinical risk factors and Ki67 expression outperformed the basic clinical model for the accurate prognostic prediction of LUSC. With the largest prognostic assessment of Ki67 from protein to mRNA level, our study highlights that Ki67 also has an important prognostic value in NSCLC, but separate evaluation of LUAD and LUSC is necessary to provide more valuable information for clinical decision-making in NSCLC.
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Carcinoma Pulmonar de Células não Pequenas , Imuno-Histoquímica , Antígeno Ki-67 , Neoplasias Pulmonares , Humanos , Antígeno Ki-67/metabolismo , Antígeno Ki-67/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Prognóstico , Feminino , Masculino , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica , Pessoa de Meia-Idade , Idoso , Nomogramas , Microambiente Tumoral/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Transição Epitelial-Mesenquimal/genética , Estudos RetrospectivosRESUMO
BACKGROUND: Aging is a prominent risk factor for diverse diseases; therefore, an in-depth understanding of its physiological mechanisms is required. Nonhuman primates, which share the closest genetic relationship with humans, serve as an ideal model for exploring the complex aging process. However, the potential of the nonhuman primate animal model in the screening of human aging markers is still not fully exploited. Multiomics analysis of nonhuman primate peripheral blood offers a promising approach to evaluate new therapies and biomarkers. This study explores aging-related biomarker through multilayer omics, including transcriptomics (mRNA, lncRNA, and circRNA) and proteomics (serum and serum-derived exosomes) in rhesus monkeys (Macaca mulatta). RESULTS: Our findings reveal that, unlike mRNAs and circRNAs, highly expressed lncRNAs are abundant during the key aging period and are associated with cancer pathways. Comparative analysis highlighted exosomal proteins contain more types of proteins than serum proteins, indicating that serum-derived exosomes primarily regulate aging through metabolic pathways. Finally, eight candidate aging biomarkers were identified, which may serve as blood-based indicators for detecting age-related brain changes. CONCLUSIONS: Our results provide a comprehensive understanding of nonhuman primate blood transcriptomes and proteomes, offering novel insights into the aging mechanisms for preventing or treating age-related diseases.
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Envelhecimento , Biomarcadores , Exossomos , Macaca mulatta , Proteômica , Animais , Envelhecimento/genética , Biomarcadores/sangue , Exossomos/metabolismo , Exossomos/genética , Proteômica/métodos , Transcriptoma , Perfilação da Expressão Gênica , RNA Longo não Codificante/genética , RNA Longo não Codificante/sangue , RNA Longo não Codificante/metabolismo , Modelos Animais , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteoma/metabolismo , Genômica/métodosRESUMO
Oxygen-vacancy (Ov) engineering is an effective strategy to manipulate the electronic configuration of catalysts for electrochemical nitrogen reduction reaction (eNRR). The influence of the stable facet on the electronic configuration of Ov is widely studied, however, the effect of the reactive facet on the local electron density of Ov is unveiled. In this work, an eNRR electrode R(111)-TiO2/HGO is provided with a high proportion exposed reactive facet (111) of rutile-TiO2 (denoted as R(111)-TiO2) nanocrystals with Ov anchored in hierarchically porous graphite oxide (HGO) nanofilms. The R(111)-TiO2/HGO exhibits excellent eNRR performance with an NH3 yield rate of 20.68 µg h-1 cm-2, which is ≈20 times the control electrode with the most stable facet (110) exposed (R(110)-TiO2/HGO). The experimental data and theoretical simulations reveal that the crystal facet (111) has a positive effect on regulating the local electron density around the oxygen vacancy and the two adjacent Ti-sites, promoting the π-back-donation, minimizing the eNRR barrier, and transforming the rate determination step to *NNHâ*NNHH. This work illuminates the effect of crystal facet on the performance of eNRR, and offers a novel strategy to design efficient eNRR catalysts.
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The rhizosphere microbiome plays critical roles in plant growth and provides promising solutions for sustainable agriculture. While the rhizosphere microbiome frequently fluctuates with the soil environment, recent studies have demonstrated that a small proportion of the microbiome is consistently assembled in the rhizosphere of a specific plant genotype regardless of the soil condition, which is determined by host genetics. Based on these breakthroughs, which involved exploiting the plant-beneficial function of the rhizosphere microbiome, we propose to divide the rhizosphere microbiome into environment-dominated and plant genetic-dominated components based on their different assembly mechanisms. Subsequently, two strategies to explore the different rhizosphere microbiome components for agricultural production are suggested, that is, the precise management of the environment-dominated rhizosphere microbiome by agronomic practices, and the elucidation of the plant genetic basis of the plant genetic-dominated rhizosphere microbiome for breeding microbiome-assisted crop varieties. We finally present the major challenges that need to be overcome to implement strategies for modulating these two components of the rhizosphere microbiome.
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Agricultura , Microbiota , Rizosfera , Agricultura/métodos , Produtos Agrícolas/microbiologia , Desenvolvimento Sustentável , Microbiologia do SoloRESUMO
Nitrogen fertilizer is widely used in agriculture to boost crop yields. Plant growth-promoting rhizobacteria (PGPRs) can increase plant nitrogen use efficiency through nitrogen fixation and organic nitrogen mineralization. However, it is not known whether they can activate plant nitrogen uptake. In this study, we investigated the effects of volatile compounds (VCs) emitted by the PGPR strain Bacillus velezensis SQR9 on plant nitrogen uptake. Strain SQR9 VCs promoted nitrogen accumulation in both rice and Arabidopsis. In addition, isotope labeling experiments showed that strain SQR9 VCs promoted the absorption of nitrate and ammonium. Several key nitrogen-uptake genes were up-regulated by strain SQR9 VCs, such as AtNRT2.1 in Arabidopsis and OsNAR2.1, OsNRT2.3a, and OsAMT1 family members in rice, and the deletion of these genes compromised the promoting effect of strain SQR9 VCs on plant nitrogen absorption. Furthermore, calcium and the transcription factor NIN-LIKE PROTEIN 7 play an important role in nitrate uptake promoted by strain SQR9 VCs. Taken together, our results indicate that PGPRs can promote nitrogen uptake through regulating plant endogenous signaling and nitrogen transport pathways.
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Arabidopsis , Bacillus , Nitrogênio , Oryza , Transdução de Sinais , Bacillus/metabolismo , Bacillus/fisiologia , Bacillus/genética , Nitrogênio/metabolismo , Oryza/microbiologia , Oryza/metabolismo , Oryza/genética , Arabidopsis/metabolismo , Arabidopsis/microbiologia , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Compostos Orgânicos Voláteis/metabolismoRESUMO
BACKGROUND: Percutaneous coronary intervention (PCI) with primary stenting, which stands for stent implantation regardless of obtaining satisfactory results with balloon angioplasty, has superseded conventional plain old balloon angioplasty with provisional stenting. With drug-coated balloon (DCB), primary DCB angioplasty with provisional stenting has shown non-inferiority to primary stenting for de novo coronary small vessel disease. However, the long-term efficacy and safety of such a strategy to the primary stenting on clinical endpoints in de novo lesions without vessel diameter restrictions remain uncertain. STUDY DESIGN: The REC-CAGEFREE I is an investigator-initiated, multicenter, randomized, open-label trial aimed to enroll 2270 patients with acute or chronic coronary syndrome from 43 interventional cardiology centers in China to evaluate the non-inferiority of primary paclitaxel-coated balloons angioplasty to primary stenting for the treatment of de novo, non-complex lesions without vessel diameter restrictions. Patients who fulfill all the inclusion and exclusion criteria and have achieved a successful lesion pre-dilatation will be randomly assigned to the two arms in a 1:1 ratio. Protocol-guided DCB angioplasty and bailout stenting after unsatisfactory angioplasty are mandatory in the primary DCB angioplasty group. The second-generation sirolimus-eluting stent will be used as a bailout stent in the primary DCB angioplasty group and the treatment device in the primary stenting group. The primary endpoint is the incidence of Device-oriented Composite Endpoint (DoCE) within 24 months after randomization, including cardiac death, target vessel myocardial infarction, and clinically and physiologically indicated target lesion revascularization. DISCUSSION: The ongoing REC-CAGEFREE I trial is the first randomized trial with a clinical endpoint to assess the efficacy and safety of primary DCB angioplasty for the treatment of de novo, non-complex lesions without vessel diameter restrictions. If non-inferiority is shown, PCI with primary DCB angioplasty could be an alternative treatment option to primary stenting. TRIAL REGISTRATION: Registered on clinicaltrial.gov (NCT04561739).
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Angioplastia Coronária com Balão , Cateteres Cardíacos , Fármacos Cardiovasculares , Materiais Revestidos Biocompatíveis , Doença da Artéria Coronariana , Paclitaxel , Humanos , Angioplastia Coronária com Balão/instrumentação , Angioplastia Coronária com Balão/efeitos adversos , Angioplastia Coronária com Balão/mortalidade , Resultado do Tratamento , Fármacos Cardiovasculares/administração & dosagem , Fármacos Cardiovasculares/efeitos adversos , China , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Doença da Artéria Coronariana/terapia , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Fatores de Tempo , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Stents , Idoso , Stents Farmacológicos , Estudos de Equivalência como Asunto , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Alcohol use disorder (AUD) has been associated with attentional deficits and impairments of working memory. Meanwhile, attention and working memory are critical for time perception. However, it remains unclear how time perception alters in AUD patients and how attention and working memory affect their time perception. The current study aims to clarify the time perception characteristics of AUD patients and the cognitive mechanisms underlying their time perception dysfunction. Thirty-one patients (three of them were excluded) with AUD and thirty-one matched controls completed the Time Bisection Task, Attention Network Test and Digital Span Backward Test to assess their abilities in time perception, attention network and working memory, respectively. The results showed that, after controlling for anxiety, depression, and impulsivity, AUD patients had a lower proportion of 'long' responses at intervals of 600, 750, 900, 1050 and 1200 ms. Furthermore, they displayed higher subjective equivalence points and higher Weber ratios compared to controls. Moreover, AUD patients showed impaired alerting and executive control networks as well as reduced working memory resources. Only working memory resources mediated the impact of AUD on time perception. In conclusion, our findings suggested that the duration underestimation in AUD patients is predominantly caused by working memory deficits.
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Alcoolismo , Percepção do Tempo , Humanos , Memória de Curto Prazo/fisiologia , Função Executiva/fisiologia , Consumo de Bebidas AlcoólicasRESUMO
OBJECTIVE: Early diagnosis of osteoporosis is crucial to prevent osteoporotic vertebral fracture and complications of spine surgery. We aimed to conduct a hybrid transformer convolutional neural network (HTCNN)-based radiomics model for osteoporosis screening in routine CT. METHODS: To investigate the HTCNN algorithm for vertebrae and trabecular segmentation, 92 training subjects and 45 test subjects were employed. Furthermore, we included 283 vertebral bodies and randomly divided them into the training cohort (n = 204) and test cohort (n = 79) for radiomics analysis. Area receiver operating characteristic curves (AUCs) and decision curve analysis (DCA) were applied to compare the performance and clinical value between radiomics models and Hounsfield Unit (HU) values to detect dual-energy X-ray absorptiometry (DXA) based osteoporosis. RESULTS: HTCNN algorithm revealed high precision for the segmentation of the vertebral body and trabecular compartment. In test sets, the mean dice scores reach 0.968 and 0.961. 12 features from the trabecular compartment and 15 features from the entire vertebral body were used to calculate the radiomics score (rad score). Compared with HU values and trabecular rad-score, the vertebrae rad-score suggested the best efficacy for osteoporosis and non-osteoporosis discrimination (training group: AUC = 0.95, 95%CI 0.91-0.99; test group: AUC = 0.97, 95%CI 0.93-1.00) and the differences were significant in test group according to the DeLong test (p < 0.05). CONCLUSIONS: This retrospective study demonstrated the superiority of the HTCNN-based vertebrae radiomics model for osteoporosis discrimination in routine CT.
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Osteoporose , Fraturas por Osteoporose , Humanos , Absorciometria de Fóton , Densidade Óssea , Vértebras Lombares/diagnóstico por imagem , Redes Neurais de Computação , Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/diagnóstico por imagem , Radiômica , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Distribuição AleatóriaRESUMO
The rapid development of deep neural networks has attracted significant attention in the infrared and visible image fusion field. However, most existing fusion models have many parameters and consume high computational and spatial resources. This paper proposes a fast and efficient recursive fusion neural network model to solve this complex problem that few people have touched. Specifically, we designed an attention module combining a traditional fusion knowledge prior with channel attention to extract modal-specific features efficiently. We used a shared attention layer to perform the early fusion of modal-shared features. Adopting parallel dilated convolution layers further reduces the network's parameter count. Our network is trained recursively, featuring minimal model parameters, and requires only a few training batches to achieve excellent fusion results. This significantly reduces the consumption of time, space, and computational resources during model training. We compared our method with nine SOTA methods on three public datasets, demonstrating our method's efficient training feature and good fusion results.
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Pavement condition monitoring is an important task in road asset management and efficient abnormal pavement condition detection is critical for timely conservation management decisions. The present work introduces a mobile pavement condition monitoring approach utilizing low-cost sensor technology and machine-learning-based methodologies. Specifically, an on-board unit (OBU) embedded with an inertial measurement unit (IMU) and global positioning system (GPS) is applied to collect vehicle posture data in real time. Through a comprehensive analysis of both time domain and frequency domain data features for both normal and abnormal pavement conditions, feature engineering is conducted to identify how the most important features affect abnormal pavement condition recognition. Six machine learning models are then developed to identify different types of pavement conditions. The performance of different algorithms and the significance of different features are then analyzed. Moreover, the influence of vehicle speed on pavement condition assessment is further examined and classification models for different speed intervals are developed. The results indicate that the random forest (RF) model that considers vehicle speed achieves the best performance in pavement condition monitoring. The outcomes of the present work would contribute to cost-effective pavement condition monitoring and provide an important reference for pavement maintenance sectors.
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Importance: Adjuvant and neoadjuvant immunotherapy have improved clinical outcomes for patients with early-stage non-small cell lung cancer (NSCLC). However, the optimal combination of checkpoint inhibition with chemotherapy remains unknown. Objective: To determine whether toripalimab in combination with platinum-based chemotherapy will improve event-free survival and major pathological response in patients with stage II or III resectable NSCLC compared with chemotherapy alone. Design, Setting, and Participants: This randomized clinical trial enrolled patients with stage II or III resectable NSCLC (without EGFR or ALK alterations for nonsquamous NSCLC) from March 12, 2020, to June 19, 2023, at 50 participating hospitals in China. The data cutoff date for this interim analysis was November 30, 2022. Interventions: Patients were randomized in a 1:1 ratio to receive 240 mg of toripalimab or placebo once every 3 weeks combined with platinum-based chemotherapy for 3 cycles before surgery and 1 cycle after surgery, followed by toripalimab only (240 mg) or placebo once every 3 weeks for up to 13 cycles. Main Outcomes and Measures: The primary outcomes were event-free survival (assessed by the investigators) and the major pathological response rate (assessed by blinded, independent pathological review). The secondary outcomes included the pathological complete response rate (assessed by blinded, independent pathological review) and adverse events. Results: Of the 501 patients randomized, 404 had stage III NSCLC (202 in the toripalimab + chemotherapy group and 202 in the placebo + chemotherapy group) and 97 had stage II NSCLC and were excluded from this interim analysis. The median age was 62 years (IQR, 56-65 years), 92% of patients were male, and the median follow-up was 18.3 months (IQR, 12.7-22.5 months). For the primary outcome of event-free survival, the median length was not estimable (95% CI, 24.4 months-not estimable) in the toripalimab group compared with 15.1 months (95% CI, 10.6-21.9 months) in the placebo group (hazard ratio, 0.40 [95% CI, 0.28-0.57], P < .001). The major pathological response rate (another primary outcome) was 48.5% (95% CI, 41.4%-55.6%) in the toripalimab group compared with 8.4% (95% CI, 5.0%-13.1%) in the placebo group (between-group difference, 40.2% [95% CI, 32.2%-48.1%], P < .001). The pathological complete response rate (secondary outcome) was 24.8% (95% CI, 19.0%-31.3%) in the toripalimab group compared with 1.0% (95% CI, 0.1%-3.5%) in the placebo group (between-group difference, 23.7% [95% CI, 17.6%-29.8%]). The incidence of immune-related adverse events occurred more frequently in the toripalimab group. No unexpected treatment-related toxic effects were identified. The incidence of grade 3 or higher adverse events, fatal adverse events, and adverse events leading to discontinuation of treatment were comparable between the groups. Conclusions and Relevance: The addition of toripalimab to perioperative chemotherapy led to a significant improvement in event-free survival for patients with resectable stage III NSCLC and this treatment strategy had a manageable safety profile. Trial Registration: ClinicalTrials.gov Identifier: NCT04158440.
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Anticorpos Monoclonais Humanizados , Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Compostos de Platina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Resposta Patológica Completa , Antineoplásicos/uso terapêutico , Terapia Combinada , Compostos de Platina/administração & dosagem , Compostos de Platina/uso terapêutico , IdosoRESUMO
Finding the most interesting areas of an image is the aim of saliency detection. Conventional methods based on low-level features rely on biological cues like texture and color. These methods, however, have trouble with processing complicated or low-contrast images. In this paper, we introduce a deep neural network-based saliency detection method. First, using semantic segmentation, we construct a pixel-level model that gives each pixel a saliency value depending on its semantic category. Next, we create a region feature model by combining both hand-crafted and deep features, which extracts and fuses the local and global information of each superpixel region. Third, we combine the results from the previous two steps, along with the over-segmented superpixel images and the original images, to construct a multi-level feature model. We feed the model into a deep convolutional network, which generates the final saliency map by learning to integrate the macro and micro information based on the pixels and superpixels. We assess our method on five benchmark datasets and contrast it against 14 state-of-the-art saliency detection algorithms. According to the experimental results, our method performs better than the other methods in terms of F-measure, precision, recall, and runtime. Additionally, we analyze the limitations of our method and propose potential future developments.
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Nonaqueous organic aluminum batteries are considered as promising high-safety energy storage devices due to stable ionic liquid electrolytes and Al metals. However, the stability and capacity of organic positive electrodes are limited by their inherent high solubility and low active organic molecules. To address such issues, here porphyrin compounds with rigid molecular structures present stable and reversible capability in electrochemically storing AlCl2 +. Comparison between the porphyrin molecules with electron-donating groups (TPP-EDG) and with electron-withdrawing groups (TPP-EWG) suggests that EDG is responsible for increasing both highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels, resulting in decreased redox potentials. On the other hand, EWG is associated with decreasing both HOMO and LUMO energy levels, leading to promoted redox potentials. EDG and EWG play critical roles in regulating electron density of porphyrin π bond and electrochemical energy storage kinetics behavior. The competitive mechanism between electrochemical redox reaction and de/adsorption processes suggests that TPP-OCH3 delivers the highest specific capacity ~171.8â mAh g-1, approaching a record in the organic Al batteries.
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Soil-beneficial microbes in the rhizosphere play important roles in improving plant growth and health. Root exudates play key roles in plant-microbe interactions and rhizobacterial colonization. This review describes the factors influencing the dynamic interactions between root exudates and the soil microbiome in the rhizosphere, including plant genotype, plant development, and environmental abiotic and biotic factors. We also discuss the roles of specific metabolic mechanisms, regulators, and signals of beneficial soil bacteria in terms of colonization ability. We highlight the latest research progress on the roles of root exudates in regulating beneficial rhizobacterial colonization. Organic acids, amino acids, sugars, sugar alcohols, flavonoids, phenolic compounds, volatiles, and other secondary metabolites are discussed in detail. Finally, we propose future research objectives that will help us better understand the role of root exudates in root colonization by rhizobacteria and promote the sustainable development of agriculture and forestry.
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In this paper, a comparative study of the mode-I fracture behaviors of two types of specimens with a V-notch defect under plane stress conditions was performed using the digital gradient sensing (DGS) method. First, two types of specimens (namely one-piece specimen and bonded specimen) with the same V-notch defect were both made of polymethyl methacrylate (PMMA), and three different V-notch angles' defect were considered for each type of specimen. Then, three-point bending tests were performed on both types of specimens. The angular deflection field of light near the V-notch region was recorded using a CCD during the experiments. Finally, by utilizing the relationship between the stress gradient and angular deflection as established by the elasto-optic effect, in conjunction with the principles of linear elastic fracture mechanics theory, the stress intensity factors (SIFs) of two types of specimens under different stress conditions were calculated using the least square method. According to the experimental results, the influence of V-notch angle on fracture load and fracture toughness of two kinds of specimens was discussed. Meanwhile, the experimental results show the significant differences in the fracture behaviors of the two types of specimens under mode-I loading conditions.
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Incipient degradation dynamic detection is crucial for preventing serious accidents in the context of rolling bearing online automatic condition monitoring and preventive maintenance. This article presents a novel framework, cyclostationarity-sensitive spectrum fuzzy entropy-assisted Bayesian online anomaly inference (CSFE-BOAI), to address this challenge. A new health index, CSFE, is first defined by performing the fuzzy entropy measure on the extracted cyclostationarity-sensitive spectra to promote incipient-degradation sensitivity and robustness to interferences. Next, the BOAI procedure for detecting anomalies in continuously arriving CSFEs is derived using the robust generalized T-distribution as the underlying predictive distribution. Eventually, the CSFE-BOAI framework is constructed for bearing incipient degradation dynamic detection, which possesses double confirmation of valid anomalies through the Pauta criterion and cyclostationarity-sensitive spectrum. Experimental verifications are performed on two typical bearing degradation data and one healthy-to-incipient defect data. Results show that CSFE-BOAI enables effective and timely incipient degradation alarm and identification of rolling bearings. The comparisons with the eight advanced health indexes and four anomaly detection approaches demonstrate that CSFE-BOAI has the lowest false and missed alarms and therefore has good deployment potential for practical applications.
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Measuring bacterial colonization on Arabidopsis thaliana root is one of the most frequent experiments in plant-microbe interaction studies. A standardized method for measuring bacterial colonization in the rhizosphere is necessary to improve reproducibility. We first cultured sterile A.thaliana in hydroponic conditions and then inoculated the bacterial cells in the rhizosphere at a final concentration of OD600 of 0.01. At 2 days post-inoculation, the root tissue was harvested and washed three times in sterile water to remove the uncolonized bacterial cells. The roots were then weighed, and the bacterial cells colonized on the root were collected by vortex. The cell suspension was diluted in a gradient with a phosphate-buffered saline (PBS) buffer, followed by plating onto a Luria-Bertani (LB) agar medium. The plates were incubated at 37 °C for 10 h, and then, the single colonies on LB plates were counted and normalized to indicate the bacterial cells colonized on roots. This method is used to detect bacterial colonization in the rhizosphere in mono-interaction conditions, with good reproducibility.
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Arabidopsis , Hidroponia , Reprodutibilidade dos Testes , Meios de Cultura , Interações MicrobianasRESUMO
Grafting is a traditional and significant strategy to suppress soil-borne diseases, such as the crown gall disease caused by tumorigenic Agrobacterium and Rhizobium. Root exudates and the rhizosphere microbiome play critical roles in controlling crown gall disease, but their roles in suppressing crown gall disease in grafted plants remain unclear. Here, disease-susceptible cherry rootstock 'Gisela 6' and disease-resistant cherry rootstock 'Haiying 1' were grafted onto each other or self-grafted. The effect of their root exudates on the soil microbiome composition and the abundance of pathogenic Agrobacterium were studied. Grafting onto the disease-resistant rootstock helped to reduce the abundance of pathogenic Agrobacterium, accompanied by altering root exudation, enriching potential beneficial bacteria, and changing soil function. Then, the composition of the root exudates from grafted plants was analyzed and the potential compounds responsible for decreasing pathogenic Agrobacterium abundance were identified. Based on quantitative measurement of the concentrations of the compounds and testing the impacts of supplied pure chemicals on abundance and chemotaxis of pathogenic Agrobacterium and potential beneficial bacteria, the decreased valine in root exudates of the plant grafted onto resistant rootstock was found to contribute to decreasing Agrobacterium abundance, enriching some potential beneficial bacteria and suppressing crown gall disease. This study provides insights into the mechanism whereby grafted plants suppress soil-borne disease.