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1.
Front Microbiol ; 15: 1348680, 2024.
Article in English | MEDLINE | ID: mdl-38572240

ABSTRACT

Root rot is one of the main reasons for yield losses of red kidney bean (Phaseolus vulgaris) production. Pre-inoculation with Trichoderma harzianum can effectively lower the incidence of red kidney bean root rot. In this study, four treatments including CK (control), Fu13 (Fusarium oxysporum), T891 (T. harzianum) and T891 + Fu13 (T. harzianum + F. oxysporum) were arranged in a pot experiment to investigate how T891 affected the incidence and severity of root rot, plant growth, and changes of defense enzyme activity in red kidney bean plants. Community composition and diversity of the rhizosphere microbiota was evaluated through high-throughput sequencing, and co-occurrence network was analyzed. The results showed that when compared to the Fu13 treatment, pre-inoculation with T891 reduced the incidence and severity of red kidney bean root rot by 40.62 and 68.03% (p < 0.05), increased the root length, shoot length, total dry biomass by 48.63, 97.72, 122.17%. Upregulated activity of super-oxide dismutase (SOD), peroxidase (POD), catalase (CAT) by 7.32, 38.48, 98.31% (p < 0.05), and reduced malondialdehyde (MDA) by 23.70% (p < 0.05), respectively. Microbiological analyses also showed that F. oxysporum reduced alpha diversity resulting in alteration the composition of the rhizosphere microbial community in red kidney bean. T891 significantly reduced abundance of F. oxysporum, allowing the enrichment of potentially beneficial bacteria Porphyrobacter (ASV 46), Lysobacter (ASV 85), Microbacteriaceae (ASV 105), and Gemmatimonas (ASV 107), resulting in a more stable structure of the microbial network. The results of random forest analysis further revealed that ASV 46 (Porphyrobacter) was the primary influencing factor for the incidence of root rot after inoculation with T891, while ASV 85 (Lysobacter) was the primary influencing factor for the biomass of red kidney bean. In conclusion, T. harzianum promotes the growth of red kidney bean and inhibits root rot by improving plant antioxidant enzyme activity and regulating the rhizosphere microbial community.

2.
Comput Methods Programs Biomed ; 247: 108105, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38447316

ABSTRACT

BACKGROUND AND OBJECTIVE: Electroencephalogram (EEG) signals record brain activity, with growing interest in quantifying neural activity through complexity analysis as a potential biological marker for schizophrenia. Presently, EEG complexity analysis primarily relies on manual feature extraction, which is subjective and yields varied findings in studies involving schizophrenia and healthy controls. METHODS: This study aims to leverage deep learning methods for enhanced EEG complexity exploration, aiding early schizophrenia screening and diagnosis. Our proposed approach utilizes a three-dimensional Convolutional Neural Network (3DCNN) to extract enhanced data features for early schizophrenia identification and subsequent complexity analysis. Leveraging the spatiotemporal capabilities of 3DCNN, we extract advanced latent features and employ knowledge distillation to reintegrate these features into the original channels, creating feature-enhanced data. RESULTS: We employ a 10-fold cross-validation strategy, achieving the average accuracies of 99.46% and 98.06% in subject-dependent experiments on Dataset 1(14SZ and 14HC) and Dataset 2 (45SZ and 39HC). The average accuracy for subject-independent is 96.04% and 92.67% on both datasets. Feature extraction and classification are conducted on both the re-aggregated data and the original data. Our results demonstrate that re-aggregated data exhibit superior classification performance and a more stable training process after feature extraction. In the complexity analysis of re-aggregated data, we observe lower entropy features in schizophrenic patients compared to healthy controls, with more pronounced differences in the temporal and frontal lobes. Analyzing Katz's Fractal Dimension (KFD) across three sub-bands of lobe channels reveals the lowest α band KFD value in schizophrenia patients. CONCLUSIONS: This emphasizes the ability of our method to enhance the discrimination and interpretability in schizophrenia detection and analysis. Our approach enhances the potential for EEG-based schizophrenia diagnosis by leveraging deep learning, offering superior discrimination capabilities and richer interpretive insights.


Subject(s)
Schizophrenia , Humans , Schizophrenia/diagnostic imaging , Electroencephalography , Neural Networks, Computer , Fractals , Research Design
3.
Inorg Chem ; 62(48): 19812-19820, 2023 Dec 04.
Article in English | MEDLINE | ID: mdl-37988065

ABSTRACT

In this study, four isostructural aluminum-based porphyrin metal-organic frameworks [Al-TCPP(M), M = H2 and Zn] with different morphologies and sizes were synthesized by the hydrothermal method. By adjusting the hydrothermal reaction time and the types of porphyrin ligands, Al-TCPP(M) MOFs exhibited diverse morphologies including tetragonal, rectangular, and carambola-like phase. In view of the introduction of porphyrin ligands and the strong coordination effect of Al-O units, Al-TCPP(M) MOFs exhibited good chemical stability, broad visible light harvesting capability, and fast photogenerated charge response. Four Al-TCPP(M) MOFs exhibited excellent photocatalytic activities for Cr(VI) in aqueous solution. Notably, the regulation to the nanoscale carambola-like morphology of Al-TCPP MOFs and metallization of the porphyrin ligand promoted the Cr(VI) photoreduction reaction where the catalytic activity of metallic carambola-like Al-TCPP increased 1.7 times compared to that of nonmetallic tetragonal MOFs. With the assistance of sonophotocatalysis, the Cr(VI) average reduction rates reached 0.658, 0.542, 0.785, and 0.629 mg·L-1·min-1 for Al-TCPP(H2)-24h, Al-TCPP(H2)-72h, Al-TCPP(Zn)-24h, and Al-TCPP(Zn)-72h, which are 1.2-1.4 times higher than that of photocatalysis. UV-vis absorption spectroscopy, electronic spin resonance, and fluorescence spectroscopy experiments demonstrated that the synergistic effect of photochemistry and sonochemistry promoted the transfer of photogenerated electrons from Al-TCPP(M) to Cr(VI), thus enhancing the catalytic activity. The combination of the sonophotocatalytic technology with aluminum-porphyrin MOFs may become an effective strategy to improve MOF-based photocatalytic systems.

4.
Sci Rep ; 13(1): 12076, 2023 07 26.
Article in English | MEDLINE | ID: mdl-37495578

ABSTRACT

Glaucoma is an acquired optic neuropathy, which can lead to irreversible vision loss. Deep learning(DL), especially convolutional neural networks(CNN), has achieved considerable success in the field of medical image recognition due to the availability of large-scale annotated datasets and CNNs. However, obtaining fully annotated datasets like ImageNet in the medical field is still a challenge. Meanwhile, single-modal approaches remain both unreliable and inaccurate due to the diversity of glaucoma disease types and the complexity of symptoms. In this paper, a new multimodal dataset for glaucoma is constructed and a new multimodal neural network for glaucoma diagnosis and classification (GMNNnet) is proposed aiming to address both of these issues. Specifically, the dataset includes the five most important types of glaucoma labels, electronic medical records and four kinds of high-resolution medical images. The structure of GMNNnet consists of three branches. Branch 1 consisting of convolutional, cyclic and transposition layers processes patient metadata, branch 2 uses Unet to extract features from glaucoma segmentation based on domain knowledge, and branch 3 uses ResFormer to directly process glaucoma medical images.Branch one and branch two are mixed together and then processed by the Catboost classifier. We introduce a gradient-weighted class activation mapping (Grad-GAM) method to increase the interpretability of the model and a transfer learning method for the case of insufficient training data,i.e.,fine-tuning CNN models pre-trained from natural image dataset to medical image tasks. The results show that GMNNnet can better present the high-dimensional information of glaucoma and achieves excellent performance under multimodal data.


Subject(s)
Glaucoma , Metadata , Humans , Neural Networks, Computer , Image Interpretation, Computer-Assisted/methods , Glaucoma/diagnostic imaging , Machine Learning
5.
Inorg Chem ; 61(5): 2695-2705, 2022 Feb 07.
Article in English | MEDLINE | ID: mdl-35067049

ABSTRACT

We report herein an exploration of the straightforward one-pot dual-catalysis strategy, i.e., direct combination of a photoactive coordination polymer (CP) with another metal catalyst, for carrying out the desirable photoinduced organic transformation. The strategy overcomes the necessity of the presynthesis of the metal/CP composite that has been demonstrated to be invalid in our case. A new two-dimensional CP showing the desirable properties of wide-range visible-light absorption and efficient photoinduced charge generation was synthesized via a solvothermal reaction. The synthesized CP was successfully applied to the photocatalytic C-C cross-coupling reaction via the one-pot dual-catalysis method, in combination with the simple and ligand-free palladium salt of Pd(OAc)2 as a metal catalyst. The reaction features a short reaction time, mild reaction conditions, good recyclability, and a high yield of Heck products from a broad variety of substrates. A comparative experiment showed the presynthesized Pd/CP composite was invalid for the reaction, demonstrating the significance of the one-pot dual-catalysis strategy. Mechanistic studies suggest the one-pot reaction depends on the synergy between the photocatalysis of a synthesized CP to generate reactive aryl radicals and Pd catalysis to generate target products, in which the interfacial electron transfer has been demonstrated to be vital for producing the transient and catalytically active Pd(0) species near the surface of the CP. The study shows the direct combination of a CP photocatalyst and a metal catalyst is a highly feasible method for the photochemical reaction and enhances the prospects of application of photoactive CPs.

6.
Inorg Chem ; 60(23): 18133-18140, 2021 Dec 06.
Article in English | MEDLINE | ID: mdl-34767358

ABSTRACT

Photochemical treatment of highly toxic Cr(VI) is a desirable and ecofriendly method to protect the environment and human beings. In this study, a MOF-based sonophotocatalytic system is established, in which visible-light-driven sonophotocatalytic reduction of toxic Cr(VI) to Cr(III) in water is investigated using zirconium-porphyrin metal-organic frameworks (MOFs) structured as PCN-222(M) [M = H2, Zn(II), Fe(III), Co(II)]. In the view of the synergistic effect of sonochemistry and photocatalysis, PCN-222(M) exhibited enhanced activities for Cr(VI) reduction compared with the photocatalytic process. Kinetic studies showed that apparent reaction rate constants in the sonophotocatalytic system of PCN-222(M) are 1.5-3.3 times higher than those in photocatalysis. Fluorescence and UV-vis absorption spectra measurements demonstrate that the sonophotocatalytic process promotes the transfer of photoinduced electrons from PCN-222(M) to Cr(VI), thus enhancing the catalytic performance. The innovative combination of porous MOFs and sonophotocatalytic technology might become a feasible strategy to improve the existing MOF-based photocatalytic systems.

7.
ACS Appl Mater Interfaces ; 13(29): 34114-34123, 2021 Jul 28.
Article in English | MEDLINE | ID: mdl-34269044

ABSTRACT

Herein, a novel metal-organic framework (MOF) with a pillared-layer structure was rationally synthesized to initiate intermolecular atom-transfer radical addition (ATRA) via photoinduced electron transfer activation of haloalkanes. The MOF synthesized via the controllable pillared-layer method is of excellent visible-light absorption and high chemical stability. Photocatalytic experiments show the atom transfer of various alkyl halides (R-X, X = Cl/Br/I) onto diverse olefins was successfully achieved to produce functional ATRA products. The mechanism and experimental investigations reveal the prepared MOF serves as an efficient photocatalyst with strong reduction potential to activate haloalkane substrates via photoinduced electron transfer, generating a highly reactive alkyl radical to trigger the ATRA reaction. Key events in the ATRA reaction, including alkyl radical photogeneration as well as halide transfer, have been further regulated to achieve preferable photocatalytic performance with higher yields, shorter reaction time, and desirable cycling capability. It is notable that the work is the first report on photoinduced electron transfer activation of halides by a MOF photocatalyst for the ATRA reaction, providing a new blueprint for MOFs to develop photoinduced radical reactions.

8.
Inorg Chem ; 60(12): 8672-8681, 2021 Jun 21.
Article in English | MEDLINE | ID: mdl-34100594

ABSTRACT

Metal-organic framework (MOF) materials are intriguing photocatalysts to trigger radical-mediated chemical transformations. We report herein the synthesis and characterization of a series of isomorphic MOFs which show a novel structure, wide visible-light absorption, high chemical stability, and specific redox potential. The prepared MOFs were explored for the photoinduced single-electron oxidation of thiol compounds, generating reactive thiyl radicals to afford thioethers via a convenient thiol-olefin reaction. Importantly, we provide a widely applicable strategy by combing a photoactive MOF with phosphine to modulate the generation of thiyl radical in the reaction, thereby producing a single product of the thioether without the formation of a disulfide byproduct due to the dimerization of thiyl radicals. The photocatalytic reaction takes advantage of this strategy, showing great generality where tens of thiols and olefins have been examined as coupling partners. In addition, the strategy has also been demonstrated to be effective for the reactions catalyzed by other MOFs. Mechanism studies reveal that the selective synthesis of C-S products relies on a synergy between the photoinduced generation of a thiyl radical over the MOF and the in situ cleavage of S-S bond into a S-H bond by phosphine. It is notable that the synthesized MOFs show advanced performance in comparison with classical MOFs. The work not only provides a series of novel MOF photocatalysts that are capable of photoinduced thiol-olefin coupling but also indicates the great potential of MOFs for photochemical transformations mediated by reactive radicals.

9.
Inorg Chem ; 59(8): 5386-5393, 2020 Apr 20.
Article in English | MEDLINE | ID: mdl-32216340

ABSTRACT

A series of eosin Y (EY)-embedded zirconium-based metal-organic frameworks (Zr-MOFs) were prepared by utilizing the synthetic encapsulating method. By virtue of effective resonant energy transfer between Zr-MOF and EY, not only does EY@Zr-MOF exhibit dual-emissive characteristics, but also the relative intensity of their double emission is greatly tuned with increasing EY loading quantity. As a consequence, the double emission of EY@Zr-MOF presented large distinctions in location and intensity. By using the relative fluorescence intensity instead of the absolute fluorescence intensity of emission peaks as detection signals, two EY@Zr-MOFs served as built-in self-calibrated fluorescence sensors to detect pesticides, where EY@Zr-MOF realized the selective detection of nitenpyram, a kind of nicotine pesticide. These results indicate that the integration of robust Zr-MOF and fluorescence molecules provides a new research platform for pesticide sensing and recognition.

10.
Chemistry ; 26(7): 1661-1667, 2020 Feb 03.
Article in English | MEDLINE | ID: mdl-31840324

ABSTRACT

A series of dye@MOF composites were synthesized through in situ encapsulation of luminous rhodamine B (RhB) molecules into a blue-emissive zirconium-naphthalene-based metal-organic framework (Zr-MOF). The fabricated RhB@Zr-MOF composites exhibit tunable dual-emissive characteristics due to the process of resonant energy transfer from Zr-MOF to RhB. Notably, one of the RhB@Zr-MOF composites (R@D3) exhibited a weak emission at 420 nm and a strong emission at 607 nm, for which the two emissions possess large distinctions in location and intensity and can be referenced with each other in sensing analytes. By using relative fluorescence intensity instead of their absolute fluorescence intensity as the detection signals, R@D3 served as a built-in self-calibrated platform to selectively detect Fe3+ and Cr2 O7 2- ions in water. Compared with the pristine Zr-MOF, the R@D3 composite shows enhanced sensing selectivity to Fe3+ and higher sensibility to Cr2 O7 2- . This study displays the advantages of combining organic dyes with robust Zr-MOFs in tuning fluorescence and sensing performance.

11.
ACS Appl Mater Interfaces ; 11(3): 3016-3023, 2019 Jan 23.
Article in English | MEDLINE | ID: mdl-30629427

ABSTRACT

Photocatalysis is an efficient and sustainable approach to convert solar energy into chemical energy, simultaneously supplying valuable chemicals. In this study, a novel metal-organic framework (MOF) compound is constructed from anthracene-based organic linkers, which shows visible-light absorption and efficient photoinduced charge generation property. It was applied for triggering photooxidation of benzylamines and sulfides in the presence of environmental benign oxidants of molecular oxygen or hydrogen peroxide. Results show that it is a highly selective photocatalyst for oxidation reactions to produce valuable imines or sulfoxides. We further investigate the underlying mechanism for these photocatalytic reactions by recognizing reactive oxygen species in the reactions. It has been demonstrated that the superoxide radical (O2•-), generated by electron transfer from a photoexcited MOF to oxidants, serves as the main active species for the oxidations. The work demonstrates the great potential of photoactive MOFs for the transformation of organic chemicals into valuable complexes.

12.
Chem Commun (Camb) ; 54(92): 13002-13005, 2018 Nov 15.
Article in English | MEDLINE | ID: mdl-30387789

ABSTRACT

A novel coordination polymer has been synthesized using an anthracene-based linker, and the photocatalytic properties of this visible-light-responsive compound are evaluated where it shows highly selective photooxidation of sulfides to produce sulfoxides relying on reactive species of singlet oxygen.

13.
Inorg Chem ; 57(2): 541-544, 2018 Jan 16.
Article in English | MEDLINE | ID: mdl-29280618

ABSTRACT

A new electrically conductive coordination polymer is synthesized using anthracene-incorporated organic ligand. The compound exhibits a band-like structure and long-range π-π stacking of ligand. Interestingly, the fabricated chemiresisitor using this coordination polymer shows selective sensing behavior for volatile amine detection with characteristics of quick response, good reproducibility, and room-temperature operation. This study not only presents a rare example of electrically conductive coordination polymer but also illustrates the useful application of coordination polymer for chemiresistor.

14.
Dalton Trans ; 47(3): 909-915, 2018 Jan 15.
Article in English | MEDLINE | ID: mdl-29257163

ABSTRACT

By employing a conjugated amine-functionalized dicarboxylic ligand (H2L = 2,2'-diamino-4,4'-stilbenedicarboxylic acid, H2SDCA-NH2), we have successfully synthesized and characterized a porous and visible light responsive zirconium metal-organic framework ([Zr6O4(OH)4(L)6]·8DMF, denoted as Zr-SDCA-NH2). This Zr-MOF showed good chemical stability and broad visible light absorption with an absorption edge at about 600 nm. When used as a photocatalyst, Zr-SDCA-NH2 exhibits visible-light activity for CO2 reduction with a formate formation rate of 96.2 µmol h-1 mmolMOF-1, which is higher than the series of reported amine-functionalized Zr-MOFs. Mott-Schottky measurements, photoluminescence study and photocatalytic experiments demonstrated that the Zr6 oxo cluster through the LMCT process and the organic ligand both contributed to the CO2 photoreduction. This study indicates that the combination of amino groups and highly conjugated molecules is a feasible and simple strategy to extend light absorption of the organic ligand, which is beneficial for designing a visible light responsive MOF photocatalyst.

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