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1.
Chem Commun (Camb) ; 2024 May 28.
Article in English | MEDLINE | ID: mdl-38804250

ABSTRACT

In this study, we propose a mechanochemical approach that combines mesoporous ZnO (m-ZnO) as a mechanoredox catalyst and silane-mediated atom transfer chemistry to achieve efficient hydrodehalogenation of organic halides. The reaction can be conducted under mild conditions without the use of a large amount of organic solvent. Substrates ranging from activated alkyl halides to unactivated aryl halides were converted to the corresponding debrominated hydrogenation products in moderate to excellent isolated yields (50-95%). In addition, m-ZnO can be recycled and reused without appreciable loss of catalytic activity.

2.
Small ; : e2401972, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38770749

ABSTRACT

Due to the chemical stability of graphene, synthesis of carboxylated graphene still remains challenging during the electrochemical exfoliation of graphite. In this work, a spatially confined radical addition reaction which occurs in the sub-nanometer scaled interlayers of the expanded graphene sheets for the electrochemical synthesis of highly stable carboxylated graphene is reported. Here, formate anions act as both intercalation ions and co-reactant acid for the confinement of electro-generated carboxylic radical (●COOH) in the sub-nanometer scaled interlayers, which facilitates the radical addition reaction on graphene sheets. The controllable carboxylation of graphene is realized by tuning the concentration of formate anions in the electrolyte solution. The high crystallinity of the obtained product indicates the occurrence of spatially confined ●COOH addition reaction between the sub-nanometer interlayers of expanded graphite. In addition, the carboxylated graphene have been used for water desalination and hydrogen/oxygen reduction reaction. Therefore, this work provides a new method for the in situ preparation of functionalized graphene through the electrolysis and its applications in water desalination and hydrogen/oxygen reduction reactions.

3.
Neuron ; 112(9): 1473-1486.e6, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38447577

ABSTRACT

Phasic (fast) and tonic (sustained) inhibition of γ-aminobutyric acid (GABA) are fundamental for regulating day-to-day activities, neuronal excitability, and plasticity. However, the mechanisms and physiological functions of glial GABA transductions remain poorly understood. Here, we report that the AMsh glia in Caenorhabditis elegans exhibit both phasic and tonic GABAergic signaling, which distinctively regulate olfactory adaptation and neuronal aging. Through genetic screening, we find that GABA permeates through bestrophin-9/-13/-14 anion channels from AMsh glia, which primarily activate the metabolic GABAB receptor GBB-1 in the neighboring ASH sensory neurons. This tonic action of glial GABA regulates the age-associated changes of ASH neurons and olfactory responses via a conserved signaling pathway, inducing neuroprotection. In addition, the calcium-evoked, vesicular glial GABA release acts upon the ionotropic GABAA receptor LGC-38 in ASH neurons to regulate olfactory adaptation. These findings underscore the fundamental significance of glial GABA in maintaining healthy aging and neuronal stability.


Subject(s)
Adaptation, Physiological , Caenorhabditis elegans , Neuroglia , gamma-Aminobutyric Acid , Animals , gamma-Aminobutyric Acid/metabolism , Neuroglia/metabolism , Neuroglia/physiology , Adaptation, Physiological/physiology , Smell/physiology , Caenorhabditis elegans Proteins/metabolism , Caenorhabditis elegans Proteins/genetics , Signal Transduction/physiology , Cellular Senescence/physiology , Olfactory Receptor Neurons/physiology , Olfactory Receptor Neurons/metabolism , Aging/physiology , Aging/metabolism , Receptors, GABA-A/metabolism
4.
Nat Commun ; 15(1): 2573, 2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38519487

ABSTRACT

In two-dimensional chiral metal-halide perovskites, chiral organic spacers endow structural and optical chirality to the metal-halide sublattice, enabling exquisite control of light, charge, and electron spin. The chiroptical properties of metal-halide perovskites have been measured by transmissive circular dichroism spectroscopy, which necessitates thin-film samples. Here, by developing a reflection-based approach, we characterize the intrinsic, circular polarization-dependent complex refractive index for a prototypical two-dimensional chiral lead-bromide perovskite and report large circular dichroism for single crystals. Comparison with ab initio theory reveals the large circular dichroism arises from the inorganic sublattice rather than the chiral ligand and is an excitonic phenomenon driven by electron-hole exchange interactions, which breaks the degeneracy of transitions between Rashba-Dresselhaus-split bands, resulting in a Cotton effect. Our study suggests that previous data for spin-coated films largely underestimate the optical chirality and provides quantitative insights into the intrinsic optical properties of chiral perovskites for chiroptical and spintronic applications.

5.
J Dent ; 144: 104971, 2024 May.
Article in English | MEDLINE | ID: mdl-38548165

ABSTRACT

OBJECTIVES: In prosthodontic procedures, traditional computer-aided design (CAD) is often time-consuming and lacks accuracy in shape restoration. In this study, we combined implicit template and deep learning (DL) to construct a precise neural network for personalized tooth defect restoration. METHODS: Ninety models of right maxillary central incisor (80 for training, 10 for validation) were collected. A DL model named ToothDIT was trained to establish an implicit template and a neural network capable of predicting unique identifications. In the validation stage, teeth in validation set were processed into corner, incisive, and medium defects. The defective teeth were inputted into ToothDIT to predict the unique identification, which actuated the deformation of the implicit template to generate the highly customized template (DIT) for the target tooth. Morphological restorations were executed with templates from template shape library (TSL), average tooth template (ATT), and DIT in Exocad (GmbH, Germany). RMSestimate, width, length, aspect ratio, incisal edge curvature, incisive end retraction, and guiding inclination were introduced to assess the restorative accuracy. Statistical analysis was conducted using two-way ANOVA and paired t-test for overall and detailed differences. RESULTS: DIT displayed significantly smaller RMSestimate than TSL and ATT. In 2D detailed analysis, DIT exhibited significantly less deviations from the natural teeth compared to TSL and ATT. CONCLUSION: The proposed DL model successfully reconstructed the morphology of anterior teeth with various degrees of defects and achieved satisfactory accuracy. This approach provides a more reliable reference for prostheses design, resulting in enhanced accuracy in morphological restoration. CLINICAL SIGNIFICANCE: This DL model holds promise in assisting dentists and technicians in obtaining morphology templates that closely resemble the original shape of the defective teeth. These customized templates serve as a foundation for enhancing the efficiency and precision of digital restorative design for defective teeth.


Subject(s)
Computer-Aided Design , Deep Learning , Dental Prosthesis Design , Incisor , Neural Networks, Computer , Humans , Incisor/anatomy & histology , Dental Prosthesis Design/methods , Models, Dental , Maxilla/anatomy & histology
6.
J Dent ; 143: 104929, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38458380

ABSTRACT

OBJECTIVES: To evaluate the influence of intraoral scanning coverage (IOSC) on digital implant impression accuracy in various partially edentulous situations and predict the optimal IOSC. METHODS: Five types of resin models were fabricated, each simulating single or multiple tooth loss scenarios with inserted implants and scan bodies. IOSC was subgrouped to cover two, four, six, eight, ten, and twelve teeth, as well as full arch. Each group underwent ten scans. A desktop scanner served as the reference. Accuracy was evaluated by measuring the Root mean square error (RMSE) values of scan bodies. A convolutional neural network (CNN) was trained to predict the optimal IOSC with different edentulous situations. Statistical analysis was performed using one-way ANOVA and Tukey's test. RESULTS: For single-tooth-missing situations, in anterior sites, significantly better accuracy was observed in groups with IOSC ranging from four teeth to full arch (p < 0.05). In premolar sites, IOSC spanning four to six teeth were more accurate (p < 0.05), while in molar sites, groups with IOSC encompassing two to eight teeth exhibited better accuracy (p < 0.05). For multiple-teeth-missing situations, IOSC covering four, six, and eight teeth, as well as full arch showed better accuracy in anterior gaps (p < 0.05). In posterior gaps, IOSC of two, four, six or eight teeth were more accurate (p < 0.05). The CNN predicted distinct optimal IOSC for different edentulous scenarios. CONCLUSIONS: Implant impression accuracy can be significantly impacted by IOSC in different partially edentulous situations. The selection of IOSC should be customized to the specific dentition defect condition. CLINICAL SIGNIFICANCE: The number of teeth scanned can significantly affect digital implant impression accuracy. For missing single or four anterior teeth, scan at least four or six neighboring teeth is acceptable. In lateral cases, two neighboring teeth may suffice, but extending over ten teeth, including contralateral side, might deteriorate the scan.


Subject(s)
Dental Implants , Mouth, Edentulous , Tooth Loss , Humans , Imaging, Three-Dimensional , Dental Impression Technique , Models, Dental , Dental Impression Materials , Computer-Aided Design
7.
Nanoscale ; 16(10): 5169-5176, 2024 Mar 07.
Article in English | MEDLINE | ID: mdl-38390639

ABSTRACT

Atomically thin two-dimensional transition-metal dichalcogenides (2D-TMDs) have emerged as semiconductors for next-generation nanoelectronics. As 2D-TMD-based devices typically utilize metals as the contacts, it is crucial to understand the properties of the 2D-TMD/metal interface, including the characteristics of the Schottky barriers formed at the semiconductor-metal junction. Conventional methods for investigating the Schottky barrier height (SBH) at these interfaces predominantly rely on contact-based electrical measurements with complex gating structures. In this study, we introduce an all-optical approach for non-contact measurement of the SBH, utilizing high-quality WS2/Au heterostructures as a model system. Our approach employs a below-bandgap pump to excite hot carriers from the gold into WS2 with varying thicknesses. By monitoring the resultant carrier density changes within the WS2 layers with a broadband probe, we traced the dynamics and magnitude of charge transfer across the interface. A systematic sweep of the pump wavelength enables us to determine the SBH values and unveil an inverse relationship between the SBH and the thickness of the WS2 layers. First-principles calculations reveal the correlation between the probability of injection and the density of states near the conduction band minimum of WS2. The versatile optical methodology for probing TMD/metal interfaces can shed light on the intricate charge transfer characteristics within various 2D heterostructures, facilitating the development of more efficient and scalable nano-electronic and optoelectronic technologies.

8.
Nat Commun ; 15(1): 1179, 2024 Feb 08.
Article in English | MEDLINE | ID: mdl-38332017

ABSTRACT

The active-cooling elastomer concept, originating from vascular thermoregulation for soft biological tissue, is expected to develop an effective heat dissipation method for human skin, flexible electronics, and soft robots due to the desired interface mechanical compliance. However, its low thermal conduction and poor adaptation limit its cooling effects. Inspired by the bone structure, this work reports a simple yet versatile method of fabricating arbitrary-geometry liquid metal skeleton-based elastomer with bicontinuous Gyroid-shaped phases, exhibiting high thermal conductivity (up to 27.1 W/mK) and stretchability (strain limit >600%). Enlightened by the vasodilation principle for blood flow regulation, we also establish a hydraulic-driven conformal morphing strategy for better thermoregulation by modulating the hydraulic pressure of channels to adapt the complicated shape with large surface roughness (even a concave body). The liquid metal active-cooling elastomer, integrated with the flexible thermoelectric device, is demonstrated with various applications in the soft gripper, thermal-energy harvesting, and head thermoregulation.

9.
J Am Chem Soc ; 146(3): 2187-2195, 2024 Jan 24.
Article in English | MEDLINE | ID: mdl-38216555

ABSTRACT

In recent years, optical pump-probe microscopy (PPM) has become a vital technique for spatiotemporally imaging electronic excitations and charge-carrier transport in metals and semiconductors. However, existing methods are limited by mechanical delay lines with a probe time window up to several nanoseconds (ns) or monochromatic pump and probe sources with restricted spectral coverage and temporal resolution, hindering their amenability in studying relatively slow processes. To bridge these gaps, we introduce a dual-hyperspectral PPM setup with a time window spanning from nanoseconds to milliseconds and single-nanosecond resolution. Our method features a wide-field probe tunable from 370 to 1000 nm and a pump spanning from 330 nm to 16 µm. We apply this PPM technique to study various two-dimensional metal-halide perovskites (2D-MHPs) as representative semiconductors by imaging their transient responses near the exciton resonances under both above-band gap electronic pump excitation and below-band gap vibrational pump excitation. The resulting spatially and temporally resolved images reveal insights into heat dissipation, film uniformity, distribution of impurity phases, and film-substrate interfaces. In addition, the single-nanosecond temporal resolution enables the imaging of in-plane strain wave propagation in 2D-MHP single crystals. Our method, which offers extensive spectral tunability and significantly improved time resolution, opens new possibilities for the imaging of charge carriers, heat, and transient phase transformation processes, particularly in materials with spatially varying composition, strain, crystalline structure, and interfaces.

10.
Chemistry ; 30(2): e202302934, 2024 Jan 08.
Article in English | MEDLINE | ID: mdl-37842799

ABSTRACT

It is highly challenging to activate the basal plane and minimize the π-π stacking of MoS2 sheets, thus enhancing its catalytic performance. Here, we display an approach for making well-dispersed MoS2 . By using the N-doped multi-walled carbon nanotubes (NMWCNTs) as an isolation unit, the aggregation of MoS2 sheets was effectively reduced, favoring the dispersion of Pt nanoparticles (noted as Pt/NMWCNTs-isolated-MoS2 ). Excellent bifunctional catalytic performance for methanol oxidation and oxygen reduction reaction (MOR/ORR) were demonstrated by the produced Pt/NMWCNTs-isolated-MoS2 . In comparison to Pt nanoparticles supported on MoS2 (Pt/MoS2 ), the MOR activity (2314.14 mA mgpt -1 ) and stability (317.69 mA mgpt -1 after 2 h of operation) on Pt/NMWCNTs-isolatedMoS2 were 24 and 232 times higher, respectively. As for ORR, Pt/NMWCNTs-isolated-MoS2 holds large half-wave potential (0.88 V) and high stability (92.71 % after 22 h of operation). This work presents a tactic for activating the basal planes and reducing the π-π stacking of 2D materials to satisfy their applications in electrocatalysis. In addition, the proposed sheet-isolation method can be used for fabricating other 2D materials to promote the dispersion of nanoparticles, which assist its application in other fields of energy as well as the environment.

11.
Adv Mater ; 36(3): e2308819, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37832157

ABSTRACT

The combined effects of compact TiO2 (c-TiO2 ) electron-transport layer (ETL) are investigated without and with mesoscopic TiO2 (m-TiO2 ) on top, and without and with an iodine-terminated silane self-assembled monolayer (SAM), on the mechanical behavior, opto-electronic properties, photovoltaic (PV) performance, and operational-stability of solar cells based on metal-halide perovskites (MHPs). The interfacial toughness increases almost threefold in going from c-TiO2 without SAM to m-TiO2 with SAM. This is attributed to the synergistic effect of the m-TiO2 /MHP nanocomposite at the interface and the enhanced adhesion afforded by the iodine-terminated silane SAM. The combination of m-TiO2 and SAM also offers a significant beneficial effect on the photocarriers extraction at the ETL/MHP interface, resulting in perovskite solar cells (PSCs) with power-conversion efficiency (PCE) of over 24% and 20% for 0.1 and 1 cm2 active areas, respectively. These PSCs also have exceptionally long operational-stability lives: extrapolated T80 (duration at 80% initial PCE retained) is ≈18 000 and 10 000 h for 0.1 and 1 cm2 active areas, respectively. Postmortem characterization and analyses of the operational-stability-tested PSCs are performed to elucidate the possible mechanisms responsible for the long operational-stability.

12.
Front Immunol ; 14: 1280759, 2023.
Article in English | MEDLINE | ID: mdl-38045698

ABSTRACT

Objective: This paper observes the efficacy of chemotherapy combined with CD19 and CD20 monoclonal antibodies in clearing minimal residual disease (MRD) and bridging transplantation for refractory acute B-lymphoblastic leukemia (B-ALL) in children and reviews the literature. Methods: A 4-year-old boy diagnosed with B-ALL in our hospital was treated with the SCCLG-ALL-2016 protocol. MRD and gene quantification decreased after induction but remained persistently positive, with poor efficacy. After this patient received three cycles of consolidation chemotherapy combined with blinatumomab and rituximab, MRD and fusion gene quantification became negative, and he received allogeneic hematopoietic stem cell transplantation (allo-HSCT). Results: During the use of monoclonal antibodies, neurotoxicity, CRS, or other side effects did not occur. Before transplantation, MRD became negative, and the bone marrow had been in complete remission since transplantation (13 months). Conclusion: Chemotherapy combined with blinatumomab for refractory B-ALL in children can bring a better remission rate for patients and is a means of bridging transplantation. Nevertheless, sequential CD20 monoclonal antibody therapy is the first report , and no adverse effects were observed in our case. It is well tolerated and can be used as one of the treatments for refractory B-ALL.


Subject(s)
Hematopoietic Stem Cell Transplantation , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Child, Preschool , Humans , Male , Antibodies, Monoclonal/therapeutic use , Bone Marrow , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/therapy
13.
Environ Sci Technol ; 57(51): 21917-21926, 2023 Dec 26.
Article in English | MEDLINE | ID: mdl-38091483

ABSTRACT

Co-occurrence of organic contaminants and arsenic oxoanions occurs often at polluted groundwater sites, but the effect of arsenite on the reactivity of sulfidized nanoscale zerovalent iron (SNZVI) used to remediate groundwater has not been evaluated. Here, we study the interaction of arsenite [As(III)] with SNZVI at the individual-particle scale to better understand the impacts on the SNZVI properties and reactivity. Surface and intraparticle accumulation of As was observed on hydrophilic FeS-Fe0 and hydrophobic FeS2-Fe0 particles, respectively. X-ray absorption spectroscopy indicated the presence of realgar-like As-S and elemental As0 species at low and high As/Fe concentration ratios, respectively. Single-particle inductively coupled plasma time-of-flight mass spectrometry analysis identified As-containing particles both with and without Fe. The probability of finding As-containing particles without Fe increased with the S-induced hydrophobicity of SNZVI. The interactions of SNZVI materials with coexisting arsenite inhibited their reactivity with water (∼5.8-230.7-fold), trichloroethylene (∼3.6-67.5-fold), and florfenicol (∼1.1-5.9-fold). However, the overall selectivity toward trichloroethylene and florfenicol relative to water was improved (up to 9.0-fold) because the surface-associated As increased the SNZVI hydrophobicity. These results indicate that reactions of SNZVI with arsenite can remove As from groundwater and improve the properties of SNZVI for dehalogenation selectivity.


Subject(s)
Arsenic , Arsenites , Groundwater , Trichloroethylene , Water Pollutants, Chemical , Iron/chemistry , Trichloroethylene/chemistry , Water Pollutants, Chemical/chemistry , Groundwater/chemistry , Water
14.
Am J Cancer Res ; 13(11): 5455-5465, 2023.
Article in English | MEDLINE | ID: mdl-38058801

ABSTRACT

This study aimed to evaluate the clinical efficacy of hepatic arterial infusion chemotherapy (HAIC) combined with lenvatinib and PD1 inhibitors vs. transarterial chemoembolization (TACE) combined with lenvatinib and PD1 inhibitors in the treatment of unresectable hepatocellular carcinoma (HCC) with portal vein tumor thrombosis (PVTT) and artery-portal shunts (APFs). HCC Patients with PVTT and APFs who received HAIC in combination with PD1 inhibitor or TACE in combination with lenvatinib and PD1 inhibitor from March 2019 to May 2023 in Zhongshan People's Hospital were included. The objective response rate (ORR), disease control rate (DCR), median overall survival (mOS), median progression-free survival (mPFS), median duration of response (mDOR), and adverse events (AEs) were assessed. A total of 95 patients were enrolled in this study, including 34 cases in the HAIC+L+P group and 61 cases in the TACE+L+P group. According to the RECIST1.1, the ORR was 52.9% and 27.9%, and the DCR was 100% and 88.5%, respectively (P values =0.03 and < 0.001, respectively). The mOS of HAIC+L+P group and TACE+L+P group were 25.00 and 19.30 months, respectively (P=0.035). The mPFS of the two groups were 21.74 and 8.74 months, respectively (P=0.0066). The mDOR of the two groups was 20.43 and 9.13 months, respectively (P=0.067). Compared with TACE in combination with lenvatinib and PD-1 inhibitors, HAIC (FOLFOX) in combination with lenvatinib and PD-1 inhibitors can improve tumor response and prolong OS, PFS, and DOR in HCC patients with PVTT and APFs.

15.
Environ Sci Technol ; 57(45): 17178-17188, 2023 11 14.
Article in English | MEDLINE | ID: mdl-37903754

ABSTRACT

Lattice engineering of nanomaterials holds promise in simultaneously regulating their geometric and electronic effects to promote their performance. However, local microenvironment engineering of Fe0 nanoparticles (nFe0) for efficient and selective environmental remediation is still in its infancy and lacks deep understanding. Here, we present the design principles and characterization techniques of lattice-doped nFe0 from the point of view of microenvironment chemistry at both atomic and elemental levels, revealing their crystalline structure, electronic effects, and physicochemical properties. We summarize the current knowledge about the impacts of doping nonmetal p-block elements, transition-metal d-block elements, and hybrid elements into nFe0 crystals on their local coordination environment, which largely determines their structure-property-activity relationships. The materials' reactivity-selectivity trade-off can be altered via facile and feasible approaches, e.g., controlling doping elements' amounts, types, and speciation. We also discuss the remaining challenges and future outlooks of using lattice-doped nFe0 materials in real applications. This perspective provides an intuitive interpretation for the rational design of lattice-doped nFe0, which is conducive to real practice for efficient and selective environmental remediation.


Subject(s)
Environmental Restoration and Remediation , Nanoparticles , Nanostructures , Nanoparticles/chemistry
16.
Front Plant Sci ; 14: 1211830, 2023.
Article in English | MEDLINE | ID: mdl-37670853

ABSTRACT

As a fruit with high economic value, strawberry has a short ripeness period, and harvesting at an incorrect time will seriously affect the quality of strawberries, thereby reducing economic benefits. Therefore, the timing of its harvesting is very demanding. A fine ripeness recognition can provide more accurate crop information, and guide strawberry harvest management more timely and effectively. This study proposes a fine recognition method for field strawberry ripeness that combines deep learning and image processing. The method is divided into three stages: In the first stage, self-calibrated convolutions are added to the Mask R-CNN backbone network to improve the model performance, and then the model is used to extract the strawberry target in the image. In the second stage, the strawberry target is divided into four sub-regions by region segmentation method, and the color feature values of B, G, L, a and S channels are extracted for each sub-region. In the third stage, the strawberry ripeness is classified according to the color feature values and the results are visualized. Experimental results show that with the incorporation of self-calibrated convolutions into the Mask R-CNN, the model's performance has been substantially enhanced, leading to increased robustness against diverse occlusion interferences. As a result, the final average precision (AP) has improved to 0.937, representing a significant increase of 0.039 compared to the previous version. The strawberry ripeness classification effect is the best on the SVM classifier, and the accuracy under the combined channel BGLaS reaches 0.866. The classification results are better than common manual feature extraction methods and AlexNet, ResNet18 models. In order to clarify the role of the region segmentation method, the contribution of different sub-regions to each ripeness is also explored. The comprehensive results demonstrate that the proposed method enables the evaluation of six distinct ripeness levels of strawberries in the complex field environment. This method can provide accurate decision support for strawberry refined planting management.

17.
Rev Sci Instrum ; 94(9)2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37724924

ABSTRACT

The dc and ac flux density vs magnetic field B(H) loops of Epstein electrical strips are measured in an IEC type-A permeameter with a high-quality electrical strip wound double yokes of inside length l0 = 0.2 m and inside height h0 = 0.1 m and in a long solenoid. The relevant demagnetizing and eddy-current effects are analyzed, modeled, and discussed. It is concluded that demagnetizing corrected solenoid measurement developed for determining dc B(H) loops of the material cannot be used for the ac case, owing to complicated eddy-current demagnetizing effects. Permeameter-measured ac B(H) loops with H detected by a flat H-coil of length less than l0/2 touching the strip's middle surface may be considered representative of the actual material because H is very uniform along the strip within 3l0/4. Strips with ac B(H) loops thus determined should be used to calibrate the effective magnetic path length lm of Epstein measurements, where a very nonuniform field is applied to the strips.

18.
Plants (Basel) ; 12(15)2023 Jul 28.
Article in English | MEDLINE | ID: mdl-37570959

ABSTRACT

Sugarcane mosaic disease, mainly caused by Sugarcane streak mosaic virus (SCSMV), has serious adverse effects on the yield and quality of sugarcane. Eukaryotic translation initiation factor 4E (eIF4E) is a natural resistance gene in plants. The eIF4E-mediated natural recessive resistance results from non-synonymous mutations of the eIF4E protein. In this study, two sugarcane varieties, CP94-1100 and ROC22, were selected for analysis of their differences in resistance to SCSMV. Four-base missense mutations in the ORF region of eIF4E resulted in different conserved domains. Therefore, the differences in resistance to SCSMV are due to the inherent differences in eIF4E of the sugarcane varieties. The coding regions of eIF4E included 28 SNP loci and no InDel loci, which were affected by negative selection and were relatively conserved. A total of 11 haploids encoded 11 protein sequences. Prediction of the protein spatial structure revealed three non-synonymous mutation sites for amino acids located in the cap pocket of eIF4E; one of these sites existed only in a resistant material (Yuetang 55), whereas the other site existed only in a susceptible material (ROC22), suggesting that these two sites might be related to the resistance to SCSMV. The results provide a strong basis for further analysis of the functional role of eIF4E in regulating mosaic resistance in sugarcane.

19.
Nanoscale ; 15(29): 12157-12174, 2023 Jul 27.
Article in English | MEDLINE | ID: mdl-37431630

ABSTRACT

Chlorinated benzene-containing compounds (CBCs) refer to volatile organic compounds which simultaneously contain benzene rings and Cl atoms. It has been widely believed to cause serious harm to human health and the natural environment due to high toxicity, high persistence, and refractory degradation, thus, it is urgent to develop CBC abatement technology. In this review, several CBCs control techniques are compared, and the catalytic oxidation technology stands out for its good low-temperature activity and chlorine resistance of metal oxide catalysts. Then, the common and individual reaction pathways and water impact mechanisms of CBC catalytic oxidation on transition metal catalysts are concluded. Subsequently, three typical metal oxides (namely, VOx, MnOx, and CeO2-based catalysts) are introduced in the catalytic degradation of CBCs, whose catalytic activity influence factors are also proposed on active components, support properties, surface acidity, and nanostructure (crystal, morphology, etc.). Furthermore, the effective strategies to enhance the REDOX cycle and surface acidic sites are summarized by the doping of metals, the modification of support or/and acidic groups, and the construction of nanostructures. Finally, the key points for efficient catalyst design are speculated. This review may provide ideas for the breakthroughs of activity-enhanced strategies, the design of efficient catalysts, and research on reaction-promoted mechanisms.

20.
Org Lett ; 25(24): 4571-4575, 2023 Jun 23.
Article in English | MEDLINE | ID: mdl-37290965

ABSTRACT

An effective method has been developed to facilitate the synthesis of amides and esters at ambient temperature within 5 min, in which a stable and easily accessible triflylpyridinium reagent is used. Remarkably, this method not only has a wide range of substrate compatibility but also could realize the scalable synthesis of peptide and ester via a continuous flow process. Moreover, excellent chirality retentions are presented during activation of carboxylic acid.


Subject(s)
Amides , Esters , Peptides , Carboxylic Acids
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