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1.
Appl Environ Microbiol ; 90(9): e0135924, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39171904

RESUMEN

The Altai Mountains (ALE) and the Greater Khingan Mountains (GKM) in northern China are forest regions dominated by coniferous trees. These geographically isolated regions provide an ideal setting for studying microbial biogeographic patterns. In this study, we employed high-throughput techniques to obtain DNA sequences of soil myxomycetes, bacteria, and fungi and explored the mechanisms underlying the assembly of both local and cross-regional microbial communities in relation to environmental factors. Our investigation revealed that the environmental heterogeneity in ALE and GKM significantly affected the succession and assembly of soil bacterial communities at cross-regional scales. Specifically, the optimal environmental factors affecting bacterial Bray-Curtis similarity were elevation and temperature seasonality. The spatial factors and climate change impact on bacterial communities under the geographical barriers surpassed that of local soil microenvironments. The assembly pattern of bacterial communities transitions from local drift to cross-regional heterogeneous selection. Environmental factors had a relatively weak influence on myxomycetes and fungi. Both soil myxomycetes and fungi faced considerable dispersal limitation at local and cross-regional scales, ultimately leading to weak geographical distribution patterns.IMPORTANCEThe impact of environmental selection and dispersal on the soil microbial spatial distribution is a key concern in microbial biogeography, particularly in large-scale geographical patterns. However, our current understanding remains limited. Our study found that soil bacteria displayed a distinct cross-regional geographical distribution pattern, primarily influenced by environmental selection. Conversely, the cross-regional geographical distribution patterns of soil myxomycetes and fungi were relatively weak. Their composition exhibited a weak association with the environment at local and cross-regional scales, with assembly primarily driven by dispersal limitation.


Asunto(s)
Bacterias , Hongos , Microbiota , Microbiología del Suelo , China , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Hongos/genética , Hongos/clasificación , Hongos/aislamiento & purificación , Mixomicetos/genética , Mixomicetos/clasificación , Cambio Climático , Bosques
2.
Mycologia ; : 1-12, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39208238

RESUMEN

The study of myxomycete biogeography has a long-standing history and has consistently drawn scholarly interest. Nevertheless, studies focusing specifically on the spatial and temporal distribution patterns of myxomycete diversity are relatively limited, with even fewer investigating the mechanisms driving the generation and maintenance of myxomycete diversity. Therefore, this study selected two geographically distant sampling sites within northern Chinese forests to investigate myxomycete species composition, community structure, environmental drivers, and assembly patterns under geographic barriers. We established plots in the Altai Mountains (ALE) and the Greater Khingan Mountains (GKM), gathered bark and litter, and conducted 80-day moist chamber cultures of myxomycetes. Additionally, myxomycete specimens were collected in the field simultaneously to supplement the data set. This study collected 541 myxomycete specimens belonging to 73 species from 28 genera, spanning 12 families and eight orders. The ALE and the GKM had 20 identical species, accounting for 27% of the total species. Myxomycetes from both regions exhibited abundant occurrence 18 days after cultivation, with the quantity on bark substrates notably higher than on litter. Arcyria pomiformis and Comatricha elegans were the most common species in moist chamber cultures. Mantel test outcomes revealed that environmental factors had no significant impact on myxomycete community similarity between the two areas, aligning with findings from the neutral community model analysis, indicating a predominant influence of stochastic processes on myxomycete community structure in moist chamber cultures. This study represents the first application of a quantitative framework to analyze myxomycete community assembly cultivated in moist chambers.

3.
Arch Microbiol ; 206(8): 364, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39080072

RESUMEN

Four species of myxomycetes (Arcyria pseudodenudata, Diderma europaeum, Lycogala irregulare, and Trichia armillata) new to China were observed via light microscope and scanning electron microscope, and detailed descriptions and illustrations are provided, along with comparisons with related species. Among them, A. pseudodenudata was discovered for the first time outside of the type locality, D. europaeum was discovered for the first time outside of Europe, and L. irregulare and T. armillata were reported again after being named. Phylogenetic analyses based on nuclear 18S rDNA and elongation factor-1 alpha sequences or nuclear 18S rDNA and cytochrome oxidase subunit I sequences was performed to provide a molecular basis for morphological identification. These specimens were deposited in the Herbarium of Fungi of Nanjing Normal University.


Asunto(s)
Mixomicetos , Filogenia , ARN Ribosómico 18S , China , Mixomicetos/clasificación , Mixomicetos/genética , Mixomicetos/aislamiento & purificación , Mixomicetos/ultraestructura , ARN Ribosómico 18S/genética , ADN Ribosómico/genética , Complejo IV de Transporte de Electrones/genética , Factor 1 de Elongación Peptídica/genética , Análisis de Secuencia de ADN
4.
Eur J Protistol ; 95: 126105, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38908307

RESUMEN

After Gulielmina was erected and Ophiotheca was resurrected based on some species originally included in Perichaena (Trichiaceae, Trichiales, Myxomyxetes), some specimens from the Herbarium of Fungi of Nanjing Normal University previously identified as Perichaena species were reexamined from morphological and two-gene (nuclear 18S rDNA and elongation factor-1 alpha) phylogenetic perspectives. In this study, two new myxomycete species, Gulielmina subreticulospora and Ophiotheca dictyospora, are described. Gulielmina subreticulospora shows the following character combination: branched plasmodiocarps, single peridium with circular protrusions in the inner surface, capillitium (2.4-)2.8-3.0(-3.4) µm in diameter, spores (7.4-)8.0-8.5(-9.0) µm in diameter and sub-reticulated. Ophiotheca dictyospora shows the following character combination: sessile sporocarps to short plasmodiocarps, single peridium with a densely irregular network and protrusions in the inner surface, capillitium (2.7-)3.5-5.0(-7.1) µm in diameter, uneven, decorated with spines of uneven size, spores (7.7-)8.2-8.6(-9.4) µm in diameter including obviously complete cristate reticulation with serrated edges, with deep and clear grids. Both new taxa were compared with related species and their genetic isolation was statistically tested. Moreover, a comprehensive morphological description and a detailed figure plate are provided for Perichaena verrucifera, and its phylogenetic position is determined.


Asunto(s)
Mixomicetos , Filogenia , Especificidad de la Especie , China , Mixomicetos/clasificación , Mixomicetos/genética , ARN Ribosómico 18S/genética , ADN Ribosómico/genética
5.
J Opt Soc Am A Opt Image Sci Vis ; 41(5): 969-975, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38856583

RESUMEN

As a missile flies at high speed, the index and surface shape of the conformal dome will vary under the influence of the aero-optical effect, which will degenerate the performance of the seeker's imaging detection system. However, many previous studies on aero-optical imaging deterioration of optical domes were usually carried out under fixed operating conditions, which are not in line with the real flight scene of the missile. In addition, the aero-optical imaging degeneration of the dome is diverse as the flight time increases. Therefore, it is of great significance to study the time characteristics of aero-optical imaging degradation of optical domes under variable work conditions. In this study, taking an air-to-air missile as an example, the Zernike polynomials, wavefront aberration, Strehl ratio, and image simulation are applied to evaluate the aero-optical imaging deterioration of an ellipsoidal dome in the flight time range of 0-10 s under variable working conditions. The simulation results show that, as the flight time increases, (1) the dynamic range of tilt, defocus, astigmatism, coma, and wavefront aberration increase; and (2) the Strehl ratio and the peak signal-to-noise ratio (PSNR) of the simulated images decrease. Therefore, the influence of flight time on the aero-optical image degradation of the ellipsoidal dome gradually becomes more serious.

6.
Adv Mater ; 36(29): e2401645, 2024 Jul.
Artículo en Catalán | MEDLINE | ID: mdl-38754860

RESUMEN

Bio-inspired magnetic-responsive hydrogel is confined in exceedingly narrow spaces for soft robots and biomedicine in either gel state or magnetofluidic sol state. However, the motion of the gel state magnetic hydrogel will be inhibited in various irregular spaces due to the fixed shape and size and the sol-state magnetofluid gel may bring unpredictable residues in the confined narrow space. Inspired by the dynamic liquid lubricating mechanism of biological systems, novel magnetic-responsive semi-convertible hydrogel (MSCH) is developed through imbedding magnetic-responsive gelatin and amino-modified Fe3O4 nanoparticles network into the covalent network of polyvinyl alcohol, which can be switched between gel state and gel-sol state in response to magnetic stimuli. It can be attributed the disassembly of triple-helix structures of the gelatin under the action of the magnetic field, driven by force from the magnetic particles conjugated on the gelatin chain through electrostatic interactions, while the covalent network retains the hydrogel structural integrity. This leads to a sol layer on the MSCH surface enabling the MSCH to pass effectively through the confined channel or obstacle under magnetic field. The present MSCH will provide an alternative mode for magnetic field-related soft robots or actuators.

7.
ACS Appl Mater Interfaces ; 16(20): 26288-26298, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38725121

RESUMEN

Sulfide-based all-solid-state lithium batteries (ASSLBs) have attracted unprecedented attention in the past decade due to their excellent safety performance and high energy storage density. However, the sulfide solid-state electrolytes (SSEs) as the core component of ASSLBs have a certain stiffness, which inevitably leads to the formation of pores and cracks during the production process. In addition, although sulfide SSEs have high ionic conductivity, the electrolytes are unstable to lithium metal and have non-negligible electronic conductivity, which severely limits their practical applications. Herein, a grain boundary electronic insulation strategy through in situ polymer encapsulation is proposed for this purpose. A polymer layer with insulating properties is applied to the surface of the Li5.5PS4.5Cl1.5 (LPSC) electrolyte particles by simple ball milling. In this way, we can not only achieve a dense electrolyte pellet but also improve the stability of the Li metal anode and reduce the electronic conductivity of LPSC. This strategy of electronic isolation of the grain boundaries enables stable deposition/stripping of the modified electrolyte for more than 2000 h at a current density of 0.5 mA cm-1 in a symmetrical Li/Li cell. With this strategy, a full cell with Li(Ni0.8Co0.1Mn0.1)O2 (NCM811) as the cathode shows high performance including high specific capacity, improved high-rate capability, and long-term stability. Therefore, this study presents a new strategy to achieve high-performance sulfide SSEs.

8.
Mycologia ; 116(3): 409-417, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38442243

RESUMEN

A new myxomycete species, Arcyria similaris, was reported herein. The specimens were found and collected in the field on dead bark from Jingangtai National Geopark in Henan Province of China. This species has distinct and unique morphological characteristics, including dark grayish olive sporothecae that fade to smoke gray with age, shallow saucer-shaped cups with marked reticulations and thick papillae on the inner surface, a netted capillitium with many bulges, uniformly marked with low, dense, and irregular reticulations, and spores (8.0-)9.3-10.1(-10.9) µm in diameter, marked with sparse small warts and grouped prominent warts. Apart from a comprehensive morphological study, partial sequences of the nuclear 18S rDNA and elongation factor-1 alpha (EF-1α) genes were also provided in this study. This new species was described and illustrated morphologically. The specimens are deposited in the Herbarium of Fungi of Nanjing Normal University (HFNNU).


Asunto(s)
ADN Ribosómico , Mixomicetos , Factor 1 de Elongación Peptídica , Filogenia , ARN Ribosómico 18S , China , Mixomicetos/clasificación , Mixomicetos/genética , Mixomicetos/aislamiento & purificación , ARN Ribosómico 18S/genética , Factor 1 de Elongación Peptídica/genética , ADN Ribosómico/genética , Corteza de la Planta/microbiología , Corteza de la Planta/parasitología , Análisis de Secuencia de ADN , Datos de Secuencia Molecular
9.
Theranostics ; 14(5): 1982-2035, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38505623

RESUMEN

Many human tissues exhibit a highly oriented architecture that confers them with distinct mechanical properties, enabling adaptation to diverse and challenging environments. Hydrogels, with their water-rich "soft and wet" structure, have emerged as promising biomimetic materials in tissue engineering for repairing and replacing damaged tissues and organs. Highly oriented hydrogels can especially emulate the structural orientation found in human tissue, exhibiting unique physiological functions and properties absent in traditional homogeneous isotropic hydrogels. The design and preparation of highly oriented hydrogels involve strategies like including hydrogels with highly oriented nanofillers, polymer-chain networks, void channels, and microfabricated structures. Understanding the specific mechanism of action of how these highly oriented hydrogels affect cell behavior and their biological applications for repairing highly oriented tissues such as the cornea, skin, skeletal muscle, tendon, ligament, cartilage, bone, blood vessels, heart, etc., requires further exploration and generalization. Therefore, this review aims to fill that gap by focusing on the design strategy of highly oriented hydrogels and their application in the field of tissue engineering. Furthermore, we provide a detailed discussion on the application of highly oriented hydrogels in various tissues and organs and the mechanisms through which highly oriented structures influence cell behavior.


Asunto(s)
Materiales Biomiméticos , Hidrogeles , Humanos , Hidrogeles/química , Ingeniería de Tejidos , Cartílago , Materiales Biomiméticos/química , Huesos
10.
Molecules ; 28(19)2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37836763

RESUMEN

Here, we report a Na-promoted FeCu-based catalyst with excellent liquid hydrocarbon selectivity and catalytic activity. The physiochemical properties of the catalysts were comprehensively characterized by various characterization techniques. The characterization results indicate that the catalytic performance of the catalysts was closely related to the nature of the metal promoters. The Na-AlFeCu possessed the highest CO2 conversion due to enhanced CO2 adsorption of the catalysts by the introduction of Al species. The introduction of excess Mg promoter led to a strong methanation activity of the catalyst. Mn and Ga promoters exhibited high selectivity for light hydrocarbons due to their inhibition of iron carbides generation, resulting in a lack of chain growth capacity. The Na-ZnFeCu catalyst exhibited the optimal C5+ yield, owing to the fact that the Zn promoter improved the catalytic activity and liquid hydrocarbon selectivity by modulating the surface CO2 adsorption and carbide content. Carbon dioxide (CO2) hydrogenation to liquid fuel is considered a method for the utilization and conversion of CO2, whereas satisfactory activity and selectivity remains a challenge. This method provides a new idea for the catalytic hydrogenation of CO2 and from there the preparation of high-value-added products.

11.
Adv Mater ; 35(46): e2307705, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37742109

RESUMEN

Enabling the living capability of secreting liquids dynamically triggered by external stimuli while maintaining the bulk frame is a significant challenge for mucosa-inspired hydrogels. A mucosa-inspired electro-responsive hydrogel is developed in this study using the synergy between electro-responsive silk fibroin supramolecular non-covalent networks and covalent polyacrylamide and polyvinyl alcohol polymer networks. The formed supramolecular-covalent hydrogel exhibits a partial gel-sol transition upon the application of an electric field, and the liquid layer on the hydrogel surface near the cathode is used to mimic the mucus-secreting capability to regulate lubrication. The electro-responsive lubricating process can operate under a safe voltage and exhibits good reversibility. It is also a universal strategy to construct an electro-responsive hydrogel by introducing an electro-responsive supramolecular network into the polymer network. This mucosa-inspired electro-responsive supramolecular-covalent hydrogel offers a promising method for designing soft actuators or robots that can regulate lubrication using an electric strategy.

12.
J Cell Biochem ; 124(9): 1346-1365, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37555580

RESUMEN

Elsinochrome A (EA) is a perylene quinone natural photosensitizer, photosensitizer under light excitation generates reactive oxygen species (ROS) to induce apoptosis, so can be used for treating tumors, that is so-called photodynamic therapy (PDT). However, the molecular mechanism, especially related to apoptosis and autophagy, is still unclear. In this study, we aimed to explore the mechanism of EA-PDT-induced B16 cells apoptosis and autophagy. The action of EA-PDT on mitochondrial permeability transition pore (MPTP), mitochondrial membrane potential (MMP) and the mitochondrial function were researched by fluorescence technique and Extracellular Flux Analyzer. Illumina sequencing, tandem mass tags Quantitative Proteomics and Western Blot studied the mechanism at the gene and protein levels. The results indicated that EA-PDT had excellent phototoxicity in vitro. EA could bind to the mitochondria. EA-PDT for 5 min caused MPTP opening, MMP decreasing and abnormal mitochondrial function with a concentration-dependent characteristic. EA-PDT resulted in an increase intracellular ROS and the number of autophagosomes. Caspase2, caspase9 and tnf were upregulated, and bcl2, prkn, atg2, atg9 and atg10 were downregulated. Our results indicated that EA-PDT induced cell apoptosis and autophagy through the mediation of ROS/Atg/Parkin. This study can provide enlightenment for exploring potential targets of drug development for the PDT of melanoma.


Asunto(s)
Fotoquimioterapia , Fármacos Fotosensibilizantes , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Fotoquimioterapia/métodos , Especies Reactivas de Oxígeno/metabolismo , Línea Celular Tumoral , Apoptosis , Autofagia
13.
Small Methods ; : e2300753, 2023 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-37599261

RESUMEN

Nature offers a wealth of opportunities to solve scientific and technological issues based on its unique structures and function. The dynamic non-covalent interaction is considered to be the main base of living functions of creatures including humans, animals, and plants. Supramolecular hydrogels formed by non-covalent bonding interactions has become a unique platform for constructing promising materials for medicine, energy, electronic, and biological substitute. In this review, the self-assemble principle of supramolecular hydrogels is summarized. Next, the stimulation of external environment that triggers the assembly or disassembly of supramolecular hydrogels are recapitulated, including temperature, mechanics, light, pH, ions, etc. The main applications of bioinspired supramolecular hydrogels in terms of bionic objects including humans, animals, and plants are also described. Although so many efforts are done for revealing the synergized mechanism of the function and non-covalent interactions on the supramolecular hydrogel, the complexity and variability between stimulus and non-covalent bonding in the supramolecular system still require impeccable theories. As an outlook, the bioinspired supramolecular hydrogel is just beginning to exhibit its great potential in human life, offering significant opportunities in drug delivery and screening, implantable devices and substitutions, tissue engineering, micro-fluidic devices, and biosensors.

14.
Sci Total Environ ; 897: 165429, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37437627

RESUMEN

The bright coniferous forest area in the cold temperate zone of China is a terrestrial ecosystem primarily dominated by low mountain Larix gmelinii trees. Limited information is available regarding the assembly mechanisms and interactions of microbial communities in the soil in this region. This study employed high-throughput techniques to obtain DNA from myxomycetes, bacteria, and fungi in the soil, evaluated their diversity in conjunction with environmental factors, associated them with the assembly process, and explored the potential interaction relationships between these microorganisms. The findings of our study showed that environmental factors had a more significant influence on the α and ß diversity of bacteria compared to myxomycetes and fungi. Microbial communities were influenced by environmental selection and geographical diffusion, although environmental selection appeared to have a more significant impact than geographical diffusion. Our study suggested that different microorganisms exhibited unique evolutionary patterns and may have different assembly modes within phylogenetic groups. Myxomycetes and fungi exhibited a similar assembly process that was mainly influenced by stochastic dispersal limitation and drift. In contrast, bacteria's assembly process was primarily influenced by stochastic drift and deterministic homogeneous selection. The community of myxomycetes and fungi is greatly influenced by spatial distribution and random events, while bacteria have a relatively stable population composition in specific regions and may also be subject to environmental constraints. Finally, this study revealed that Humicolopsis cephalosporioides, a fungus that exclusively resided in cold environments, may play a critical role as a keystone species in maintaining molecular ecological networks and was considered a core member of the microbiome.


Asunto(s)
Suelo , Tracheophyta , Ecosistema , Filogenia , Microbiología del Suelo , Bosques , Hongos
15.
ACS Omega ; 8(20): 17941-17947, 2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37251164

RESUMEN

With the sustainable increase of renewable energy and the maturation of heavy vehicle market, diesel consumption would face a downward trend worldwide. Herein, we have proposed a new route for hydrocracking of light cycle oil (LCO) into aromatics and gasoline and the tandem conversion of C1-C5 hydrocarbons (byproducts) into carbon nanotubes (CNTs) and H2, and by combining the simulation with Aspen Plus software and the experimental study of C2-C5 conversion, we have built a transformation network including LCO to aromatics/gasoline, C2-C5 to CNTs and H2, the conversion of CH4 into CNTs and H2, and the cycle use of H2 with pressure swing adsorption. Mass balance, energy consumption, and economic analysis were discussed as a function of varying CNT yield and CH4 conversion. 50% of H2 required for hydrocracking of LCO can be supplied by the downstream chemical vapor deposition processes. This can greatly reduce the cost of high-priced hydrogen feedstock. If the sale price of CNTs exceeds 2170 CNY per ton, the entire process would break even for a process of dealing with 520,000 t/a LCO. These results imply the great potential of this route, considering the vast demand and the current high price of CNTs.

16.
Chemistry ; 29(37): e202300576, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37162488

RESUMEN

In order to promote the commercialization of perovskite solar cells, gas-quenching is considered to be a promising technique for perovskite film fabrication. However, when handling with methylammonium-free (MA-free) perovskites, it is often difficult to obtain high-quality perovskite films by gas-quenching. Herein, formate additives are employed to regulate the crystallization of MA-free perovskite, and improve the quality of perovskite films. Different additives of formamidine formate (FAFO) and potassium formate (KFO) is compared to investigate the role of formate groups in the crystallization of perovskite films prepared by gas-quenching. The FAFO additive facilitates the perovskite crystallization in (001) orientation whereas KFO favors for (111) orientation. The MA-free device with addition of FAFO demonstrate a champion power conversion efficiency of 20.94 %, compared to that of 20.14 % for KFO devices. In addition, FAFO device also exhibits improved thermal stability in ambient condition without encapsulation, extending the T80 lifetime by 18 times compared to the pristine device.

17.
Ecotoxicol Environ Saf ; 255: 114766, 2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-36924559

RESUMEN

With the increase in cadmium (Cd) release into the environment, it is necessary to find appropriate solutions to reduce soil Cd pollution. Microorganisms are a green and effective means for the remediation of Cd-contaminated soil. In this study, in a Cd-contaminated farmland, we screened and identified novel Cd-resistant strains, Paenarthrobactor nitroguajacolicus, Lysinibacillus fusiformis, Bacillus licheniformis, and Methyllobacium brachiatum, with minimum inhibitory concentrations of 100, 100, 50, and 50 mg/L, respectively, and added them each to pots containing Cd-contaminated rape plants to explore their remediation ability. The results showed that treatment with each of the four strains significantly increased the abundance of Nitrospirae, Firmicutes, Verrucomicrobia, and Patescibacterium in the rhizosphere soil of the plants. This led to changes in soil physical and chemical indices; pH; and available phosphorus, urease, and catalase activities, which were significantly negatively correlated with bioavailable Cd, reducing 28.74-58.82 % Cd enrichment to plants and 23.72-43.79 % Cd transport within plants, and reducing 5.52-10.68 % available cadmium in soil, effectively reducing the biotoxicity of Cd. Thus, this study suggests microbial remediation as a reliable option, forming a basis for the remediation of Cd-contaminated soil.


Asunto(s)
Cadmio , Contaminantes del Suelo , Cadmio/análisis , Biodegradación Ambiental , Contaminantes del Suelo/análisis , Bacterias , Suelo/química
18.
Sensors (Basel) ; 22(24)2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36560214

RESUMEN

Trunk pests have always been one of the most important species of tree pests. Trees eroded by trunk pests will be blocked in the transport of nutrients and water and will wither and die or be broken by strong winds. Most pests are social and distributed in the form of communities inside trees. However, it is difficult to know from the outside if a tree is infected inside. A new method for the non-invasive detecting of tree interiors is proposed to identify trees eroded by trunk pests. The method is based on electromagnetic inverse scattering. The scattered field data are obtained by an electromagnetic wave receiver. A Joint-Driven algorithm is proposed to realize the electromagnetic scattered data imaging to determine the extent and location of pest erosion of the trunk. This imaging method can effectively solve the problem of unclear imaging in the xylem of living trees due to the small area of the pest community. The Joint-Driven algorithm proposed by our group can achieve accurate imaging with a ratio of pest community radius to live tree radius equal to 1:60 under the condition of noise doping. The Joint-Driven algorithm proposed in this paper reduces the time cost and computational complexity of tree internal defect detection and improves the clarity and accuracy of tree internal defect inversion images.


Asunto(s)
Insectos , Árboles , Animales , Radiación Electromagnética , Diagnóstico por Imagen , Algoritmos
19.
Polymers (Basel) ; 14(23)2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36501518

RESUMEN

In this work, considering the current status of conservative and complicated traditional thrombosis treatment methods, a kind of flexible intelligent probe (FIP) with a top-driven sensing strategy is proposed to realize the expected function of thrombosis accurate localization in a liquid flow environment. After throughput fabrication, we find that the FIP has excellent electrical conductivity and mechanical properties. Notable, our FIP with the principle of piezo-resistive sensing has a quasi-linear sensitivity (approx. 0.325 L per minute) to flow sensing in the low flow velocity range (0-1 L per minute). Via the well-designed magnetically driven method, our FIP has a maximum deflection output force of 443.264 mN, a maximum deflection angle of 43°, and a maximum axial force of 54.176 mN. We demonstrate that the FIP is capable of completing the specified command actions relatively accurately and has a good response to real-time sensing feedback performance, which has broad application prospects in thrombus localization detection.

20.
Artículo en Inglés | MEDLINE | ID: mdl-36293983

RESUMEN

The continued development of digital technology and its overuse in teaching and learning in the post-epidemic era have brought about digital health risks, which are associated with academic burnout among college students. This study focused on the relationship between classroom digital teaching and students' academic burnout and designed the Classroom Burnout Inventory (CBI) and the Classroom Burnout Causes Inventory (CBCI) to conduct a cross-sectional survey of 206 Chinese university students. Correlations and regression analyses were conducted between key factors and burnout values through a path model of "Digital teaching-Teaching & learning process-Causes subjects-Burnout". The results of the study show that an inappropriate and excessive use of unintegrated digital teaching and learning technologies in the classroom was positively correlated with academic burnout among college students. Burnout levels and the three manifestations were not correlated with students' gender, grade, and major. In terms of causes, the academic burnout of college students was more correlated with their own personal reasons than with external factors such as teachers, universities, and environments. Integrating digital technology platforms, enhancing teacher leadership in the digital classroom, and strengthening peer support and students' psychological resilience are all meaningful explorations of academic burnout prevention strategies.


Asunto(s)
Agotamiento Profesional , COVID-19 , Humanos , Estudios Transversales , COVID-19/epidemiología , Estudiantes/psicología , Agotamiento Profesional/psicología , Agotamiento Psicológico/epidemiología
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