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1.
Proc Natl Acad Sci U S A ; 121(1): e2311402121, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38147555

RESUMEN

The planetesimals in the solar system exhibit varying degrees of moderately volatile elements (MVEs) depletion compared to the protosolar composition. Revealing the relevant mechanisms is crucial for exploring early solar system evolution. Most volatile-depleted materials in the solar system exhibit enrichments in the heavier isotopes of MVEs, which have traditionally been attributed to the loss of volatiles through partial evaporation. Angrites are so far an exception as they are enriched in the lighter isotopes of K. This has been interpreted as reflecting condensation processes. Here, we present Rb isotopic data of angrites and find that they have lighter Rb isotopic compositions than Vesta, Mars, and the Moon. The δ87Rb value of the angrite parent body (APB) is estimated to range between -1.19‰ and -0.67‰. The extremely light Rb isotopic composition of the APB is likely a result of the kinetic recondensation of Rb after near-complete evaporation during the magma ocean stage. This finding provides further support for the partial recondensation model to explain the light Rb and K isotopic compositions of the APB. In addition, the APB, alongside other terrestrial planetary bodies (e.g., Earth, Mars, Moon, and Vesta), exhibit a strong correlation between their Rb and K isotopic compositions. This coupling of Rb and K isotopes is indicative of a volatility-driven isotopic fractionation rather than nucleosynthetic anomalies. The extremely light Rb-K isotopic signatures of the APB suggest that beyond evaporation, condensation plays an equally significant role in shaping the planetary-scale distributions of volatile elements.

2.
Sensors (Basel) ; 24(17)2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39275604

RESUMEN

This work focuses on the improvement of the density peaks clustering (DPC) algorithm and its application to point cloud segmentation in LiDAR. The improvement of DPC focuses on avoiding the manual determination of the cut-off distance and the manual selection of cluster centers. And the clustering process of the improved DPC is automatic without manual intervention. The cut-off distance is avoided by forming a voxel structure and using the number of points in the voxel as the local density of the voxel. The automatic selection of cluster centers is realized by selecting the voxels whose gamma values are greater than the gamma value of the inflection point of the fitted γ curve as cluster centers. Finally, a new merging strategy is introduced to overcome the over-segmentation problem and obtain the final clustering result. To verify the effectiveness of the improved DPC, experiments on point cloud segmentation of LiDAR under different scenes were conducted. The basic DPC, K-means, and DBSCAN were introduced for comparison. The experimental results showed that the improved DPC is effective and its application to point cloud segmentation of LiDAR is successful. Compared with the basic DPC, K-means, the improved DPC has better clustering accuracy. And, compared with DBSCAN, the improved DPC has comparable or slightly better clustering accuracy without nontrivial parameters.

3.
Sensors (Basel) ; 23(6)2023 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-36991758

RESUMEN

The acquirement of the flow information in plate-fin heat exchanger (PFHE) is limited by its metal structure and complex flow condition. This work develops a new distributed optical measurement system to obtain flow information and boiling intensity. The system utilizes numerous optical fibers installed at the surface of the PFHE to detect optical signals. The attenuation and fluctuation of the signals reflect the variation of the gas-liquid interfaces and can be further used to estimate the boiling intensity. Practical experiments of flow boiling in PFHE with different heating fluxes have been carried out. The results verify that the measurement system can obtain the flow condition. Meanwhile, according to the results, the boiling development in PFHE can be divided into four stages with the increase in the heating flux, including the unboiling stage, initiation stage, boiling developing stage, and fully developed stage.

4.
Entropy (Basel) ; 25(1)2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-36673289

RESUMEN

Regularization with priors is an effective approach to solve the ill-posed inverse problem of electrical tomography. Entropy priors have been proven to be promising in radiation tomography but have received less attention in the literature of electrical tomography. This work aims to investigate the image reconstruction of capacitively coupled electrical resistance tomography (CCERT) with entropy priors. Four types of entropy priors are introduced, including the image entropy, the projection entropy, the image-projection joint entropy, and the cross-entropy between the measurement projection and the forward projection. Correspondingly, objective functions with the four entropy priors are developed, where the first three are implemented under the maximum entropy strategy and the last one is implemented under the minimum cross-entropy strategy. Linear back-projection is adopted to obtain the initial image. The steepest descent method is utilized to optimize the objective function and obtain the final image. Experimental results show that the four entropy priors are effective in regularization of the ill-posed inverse problem of CCERT to obtain a reasonable solution. Compared with the initial image obtained by linear back projection, all the four entropy priors make sense in improving the image quality. Results also indicate that cross-entropy has the best performance among the four entropy priors in the image reconstruction of CCERT.

5.
Eur J Neurosci ; 56(4): 4304-4316, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35766911

RESUMEN

BACKGROUND: Circular RNAs (circRNAs) are aberrantly expressed in the central nervous system (CNS) and are involved in diverse CNS diseases. However, the functions of circRNAs in ischemic stroke (IS) are largely unknown. In this study, we aimed to explore the effect of circ_TLK1 in oxygen-glucose deprivation/reoxygenation (OGD/R)-induced PC12 cell injury. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was performed for the levels of circ_TLK1, TLK1, microRNA-136-5p (miR-136-5p), and follistatin like-1 (FSTL1). RNase R and Actinomycin D assays were conducted to analyze the features of circ_TLK1. 3-(4, 5-ethynyl-2'-deoxyuridine [EdU] assay and 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay were adopted to analyze cell proliferation capacity. Flow cytometry analysis was applied to determine cell death. Western blot assay was employed to measure protein levels. The release of lactate dehydrogenase (LDH) was measured with specific kits. The interaction between circ_TLK1 and miR-136-5p, as well as miR-136-5p and FSTL1, was verified by Dual-luciferase reporter assay. RESULTS: Circ_TLK1 was upregulated in OGD/R-injured PC12 cells. OGD/R treatment inhibited cell proliferation, promoted cell death, and increased LDH release in PC12 cells, while circ_TLK1 knockdown partially alleviated OGD/R-induced PC12 cell injury. Circ_TLK1 directly bound to miR-136-5p and miR-136-5p inhibition reversed the effect of circ_TLK1 knockdown on OGD/R-induced PC12 cell damage. Moreover, FSTL1 was targeted by miR-136-5p. MiR-136-5p upregulation inhibited PC12 cell injury induced by OGD/R, while FSTL1 overexpression partially reversed the effect. CONCLUSION: Circ_TLK1 knockdown ameliorated OGD/R-induced PC12 cell injury by modulating miR-136-5p and FSTL1, which might provide a new understanding of IS treatment.


Asunto(s)
Proteínas Relacionadas con la Folistatina , MicroARNs , Animales , Apoptosis , Proliferación Celular , Folistatina/farmacología , Proteínas Relacionadas con la Folistatina/farmacología , Glucosa/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Oxígeno/metabolismo , Células PC12 , ARN Circular/genética , Ratas
6.
Sensors (Basel) ; 22(9)2022 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-35590849

RESUMEN

In this work, an adaptive generalized cross-correlation (AGCC) method is proposed that focuses on the problem of the conventional cross-correlation method not effectively realizing the time delay estimation of signals with strong periodicity. With the proposed method, the periodicity of signals is judged and the center frequencies of the strongly periodical components are determined through the spectral analysis of the input signals. Band-stop filters that are used to suppress the strongly periodical components are designed and the mutual power spectral density of the input signals that is processed by the band-stop filters is calculated. Then, the cross-correlation function that is processed is the inverse Fourier transform of the mutual power spectral density. Finally, the time delay is estimated by seeking the peak position of the processed cross-correlation function. Simulation experiments and practical velocity measurement experiments were carried out to verify the effectiveness of the proposed AGCC method. The experimental results showed that the new AGCC method could effectively realize the time delay estimation of signals with strong periodicity. In the simulation experiments, the new method could realize the effective time delay estimation of signals with strong periodicity when the energy ratio of the strongly periodical component to the aperiodic component was under 150. Meanwhile, the cross-correlation method and other generalized cross-correlation methods fail in time delay estimation when the energy ratio is higher than 30. In the practical experiments, the velocity measurement of slug flow with strong periodicity was implemented in small channels with inner diameters of 2.0 mm, 2.5 mm and 3.0 mm. With the proposed method, the relative errors of the velocity measurement were less than 4.50%.


Asunto(s)
Periodicidad , Velocidad del Flujo Sanguíneo , Simulación por Computador , Análisis de Fourier , Ultrasonografía
7.
Phys Rev Lett ; 126(8): 084801, 2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33709748

RESUMEN

The spectroscopic techniques for time-resolved fine analysis of matter require coherent x-ray radiation with femtosecond duration and high average brightness. Seeded free-electron lasers (FELs), which use the frequency up-conversion of an external seed laser to improve temporal coherence, are ideal for providing fully coherent soft x-ray pulses. However, it is difficult to operate seeded FELs at a high repetition rate due to the limitations of present state-of-the-art laser systems. Here, we report a novel self-modulation method for enhancing laser-induced energy modulation, thereby significantly reducing the requirement of an external laser system. Driven by this scheme, we experimentally realize high harmonic generation in a seeded FEL using an unprecedentedly small external laser-induced energy modulation. An electron beam with a laser-induced energy modulation as small as 1.8 times the slice energy spread is used for lasing at the seventh harmonic of a 266-nm seed laser in a single-stage high-gain harmonic generation (HGHG) setup and the 30th harmonic of the seed laser in a two-stage HGHG setup. The results mark a major step toward a high-repetition-rate, fully coherent x-ray FEL.

8.
Sensors (Basel) ; 21(13)2021 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-34209920

RESUMEN

Electrodes are basic components of C4D (capacitively coupled contactless conductivity detection) sensors, and different electrode structures (the configuration pattern or the electrode geometry) can lead to different measurement results. In this work, the effects of electrode geometry of radial configuration on the measurement performance of C4D sensors are investigated. Two geometrical parameters, the electrode length and the electrode angle, are considered. A FEM (finite element method) model based on the C4D method is developed. With the FEM model, corresponding simulation results of conductivity measurement with different electrode geometry are obtained. Meanwhile, practical experiments of conductivity measurement are also conducted. According to the simulation results and experimental results, the optimal electrode geometry of the C4D sensor with radial configuration is discussed and proposed. The recommended electrode length is 5-10 times of the pipe inner diameter and the recommended electrode angle is 120-160°.

9.
Sensors (Basel) ; 21(19)2021 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-34640701

RESUMEN

In this work, a new capacitively coupled contactless conductivity detection (C4D) sensor for microfluidic devices is developed. By introducing an LC circuit, the working frequency of the new C4D sensor can be lowered by the adjustments of the inductor and the capacitance of the LC circuit. The limits of detection (LODs) of the new C4D sensor for conductivity/ion concentration measurement can be improved. Conductivity measurement experiments with KCl solutions were carried out in microfluidic devices (500 µm × 50 µm). The experimental results indicate that the developed C4D sensor can realize the conductivity measurement with low working frequency (less than 50 kHz). The LOD of the C4D sensor for conductivity measurement is estimated to be 2.2 µS/cm. Furthermore, to show the effectiveness of the new C4D sensor for the concentration measurement of other ions (solutions), SO42- and Li+ ion concentration measurement experiments were also carried out at a working frequency of 29.70 kHz. The experimental results show that at low concentrations, the input-output characteristics of the C4D sensor for SO42- and Li+ ion concentration measurement show good linearity with the LODs estimated to be 8.2 µM and 19.0 µM, respectively.


Asunto(s)
Dispositivos Laboratorio en un Chip , Conductividad Eléctrica , Límite de Detección
10.
Sensors (Basel) ; 20(4)2020 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-32079132

RESUMEN

Resistivity logging is an important technique for identifying and estimating reservoirs. Oil-based mud (OBM) can improve drilling efficiency and decrease operation risks, and has been widely used in the well logging field. However, the non-conductive OBM makes the traditional logging-while-drilling (LWD) method with low frequency ineffective. In this work, a new oil-based LWD method is proposed by combining the capacitively coupled contactless conductivity detection (C4D) technique and the inductive coupling principle. The C4D technique is to overcome the electrical insulation problem of the OBM and construct an effective alternating current (AC) measurement path. Based on the inductive coupling principle, an induced voltage can be formed to be the indirect excitation voltage of the AC measurement path. Based on the proposed method, a corresponding logging instrument is developed. Numerical simulation was carried out and results show that the logging instrument has good measurement accuracy, deep detection depth and high vertical resolution. Practical experiments were also carried out, including the resistance box experiment and the well logging experiment. The results of the resistance box experiment show that the logging instrument has good resistance measurement accuracy. Lastly, the results of the well logging experiment indicate that the logging instrument can accurately reflect the positions of different patterns on the wellbore of the experimental well. Both numerical simulation and practical experiments verify the feasibility and effectiveness of the new method.

11.
Sensors (Basel) ; 20(20)2020 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-33066126

RESUMEN

Capacitively coupled electrical impedance tomography (CCEIT) is a new kind of electrical resistance tomography (ERT) which realizes contactless measurement by capacitive coupling and extends traditional resistance measurement to total impedance measurement. This work investigates the performance of a CCEIT sensor with three different configurations, including the unshielded configuration, the shielded configuration A (the CCEIT sensor with the external shield) and the shielded configuration B (the CCEIT sensor with both the external shield and the radial screens). The equivalent circuit models of the measurement electrode pair of the CCEIT sensor with different configurations were developed. Additionally, three CCEIT prototypes corresponding to the three configurations were developed. Both the simulation work and experiments were carried out to compare various aspects of the three CCEIT prototypes, including the sensitivity distribution, the impedance measurement and the practical imaging performance. Simulation results show that shielded configurations improve the overall average sensitivity of the sensitivity distributions. Shielded configuration A contributes to improve the uniformity of the sensitivity distributions, while shielded configuration B reduces the uniformity in most cases. Experimental results show that the shielded configurations have no significant influence on the imaging quality of the real part of impedance measurement, but do make sense in improving the imaging performance of the imaginary part and the amplitude of impedance measurement. However, configuration B (with radial screens) has no significant advantage over configuration A (without radial screens). This work provides an insight into how shielding measures influence the performance of the CCEIT sensor, in addition to playing an important role in shielding unwanted noise and disturbances. The research results can provide a useful reference for further development of CCEIT sensors.

12.
J Cell Physiol ; 234(4): 4840-4850, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30362514

RESUMEN

MicroRNAs (miRNAs) play critical roles in various biological processes including cell differentiation. Some researchers suggested that the p38 mitogen-activated protein kinases (MAPK) signaling pathway had an effect on regulating the odontoblastic differentiation of human dental pulp stem cells (hDPSCs). This study focuses on the effects of miR-143-5p on hDPSCs by regulating the p38 MAPK signaling pathway. The targeting relationship of MAPK14 and miR-143-5p targets were verified by TargetScan and dual-luciferase reporter gene assay. Through overexpression of miR-143-5p or silencing of miR-143-5p, expressions of miR-143-5p, MAPK14, Ras, MAPK kinase (MKK) 3/6, dentin sialophosphoprotein (DSPP), alkaline phosphatase (ALP), and osteocalcin (OCN) were detected by reverse transcription quantitative polymerase chain reaction. Protein expressions of MAPK14, Ras, and MKK3/6 were determined by western blot analysis. ALP and alizarin red S staining were used to detect mineralization. Initially, MAPK14 was found to be negatively regulated by miR-143-5p. Meanwhile, the upregulated miR-143-5p decreased the p38 MAPK signaling pathway related genes (MAPK14, Ras, and MKK3/6) and odontoblastic differentiation markers (ALP, DSPP, and OCN) expression. On the contrary, the downregulated miR-143-5p increased the p38 MAPK signaling pathway related genes (MAPK14, Ras, and MKK3/6) and odontoblastic differentiation markers (ALP, DSPP, and OCN) expression. Furthermore, ALP activity and mineralized nodules increased after downregulation of miR-143-5p, and after its upregulation, ALP activity and mineralized nodules decreased. Our data suggest that poor expression of miR-143-5p promotes hDPSCs odontoblastic differentiation through the activation of the p38 MAPK signaling pathway by upregulating MAPK14.


Asunto(s)
Diferenciación Celular , Pulpa Dental/enzimología , MicroARNs/metabolismo , Proteína Quinasa 14 Activada por Mitógenos/metabolismo , Odontoblastos/enzimología , Células Madre/enzimología , Regiones no Traducidas 3' , Adulto , Fosfatasa Alcalina/genética , Fosfatasa Alcalina/metabolismo , Sitios de Unión , Pulpa Dental/citología , Regulación hacia Abajo , Activación Enzimática , Proteínas de la Matriz Extracelular/genética , Proteínas de la Matriz Extracelular/metabolismo , Femenino , Regulación Enzimológica de la Expresión Génica , Células HEK293 , Humanos , Masculino , MicroARNs/genética , Proteína Quinasa 14 Activada por Mitógenos/genética , Osteocalcina/genética , Osteocalcina/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Sialoglicoproteínas/genética , Sialoglicoproteínas/metabolismo , Transducción de Señal , Adulto Joven
13.
Sensors (Basel) ; 19(11)2019 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-31146459

RESUMEN

This work reports a new simulated inductor which is suitable for a Contactless Electrical Tomography (CET) system and can effectively overcome the unfavorable influence of coupling capacitance on the measurement results. By detailed analysis and comparison, it is found that the grounded simulated inductor has a simple circuit construction but its output current is not equal to its input current, while the floating simulated inductor can be used as an independent inductor module but its circuit structure is relatively complex. A new simulated inductor is designed by compensating the currents from the common node of an introduced independent power source to the main circuit. The new simulated inductor combines the advantages of the grounded simulated inductor and the floating simulated inductor. It has the simple construction similar to that of the grounded simulated inductor and its input current is equal to the output current, which means it can be used as an independent module. The impedance measurement and practical image reconstruction experiments were carried out to verify the effectiveness of the new simulated inductor. The experimental results show that the design of the new simulated inductor is successful, and the performance of the impedance measurement is satisfactory. The signal-to-noise ratio of the CET system is improved. Meanwhile, the research work also indicates that in the case when the independent power source is not available, the new simulated inductor is also an effective alternative method. But the phase difference between input signal and output signal is approximately 90° when the elimination principle is realized.

14.
Sensors (Basel) ; 20(1)2019 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-31861444

RESUMEN

This work proposes a new positioning method based on multiple ultrasonic sensors for the autonomous mobile robot. Unlike the conventional ultrasonic positioning methods, this new method can realize higher accuracy ultrasonic positioning without additional temperature information. Three ultrasonic sensors are used for positioning. A generalized measurement model is established for general sensor configuration. A simplified measurement model, which considers the computational complexity, is also established for linear/simplified sensor configuration. Three time-of-flight signals are obtained from the three ultrasonic sensors. The coordinates of the target are calculated by the ratios of time-of-flights. Positioning experiments were carried out to verify the feasibility and effectiveness of the proposed method. Experimental results show that the new ultrasonic positioning method is effective, both the two established models can implement positioning successfully, and the positioning accuracy is satisfactory. Compared with the conventional ultrasonic positioning method with the default ultrasonic velocity, the positioning accuracy is greatly improved by the proposed method. Compared with the ultrasonic positioning method with additional temperature compensation, the results obtained by the proposed method are comparable.

15.
Sensors (Basel) ; 16(2): 159, 2016 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-26828488

RESUMEN

Based on a laser diode, a 12 × 6 photodiode array sensor, and machine learning techniques, a new void fraction measurement method for gas-liquid two-phase flow in small channels is proposed. To overcome the influence of flow pattern on the void fraction measurement, the flow pattern of the two-phase flow is firstly identified by Fisher Discriminant Analysis (FDA). Then, according to the identification result, a relevant void fraction measurement model which is developed by Support Vector Machine (SVM) is selected to implement the void fraction measurement. A void fraction measurement system for the two-phase flow is developed and experiments are carried out in four different small channels. Four typical flow patterns (including bubble flow, slug flow, stratified flow and annular flow) are investigated. The experimental results show that the development of the measurement system is successful. The proposed void fraction measurement method is effective and the void fraction measurement accuracy is satisfactory. Compared with the conventional laser measurement systems using standard laser sources, the developed measurement system has the advantages of low cost and simple structure. Compared with the conventional void fraction measurement methods, the proposed method overcomes the influence of flow pattern on the void fraction measurement. This work also provides a good example of using low-cost laser diode as a competent replacement of the expensive standard laser source and hence implementing the parameter measurement of gas-liquid two-phase flow. The research results can be a useful reference for other researchers' works.

16.
Sensors (Basel) ; 16(2): 165, 2016 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-26828493

RESUMEN

A new capacitively coupled contactless conductivity detection (C(4)D) sensor with an improved simulated inductor is developed in this work. The improved simulated inductor is designed on the basis of the Riordan-type floating simulated inductor. With the improved simulated inductor, the negative influence of the coupling capacitances is overcome and the conductivity measurement is implemented by the series resonance principle. The conductivity measurement experiments are carried out in three pipes with different inner diameters of 3.0 mm, 4.6 mm and 6.4 mm, respectively. The experimental results show that the designs of the new C(4)D sensor and the improved simulated inductor are successful. The maximum relative error of the conductivity measurement is less than 5%. Compared with the C(4)D sensors using practical inductors, the measurement accuracy of the new C(4)D sensor is comparable. The research results also indicate that the adjustability of a simulated inductor can reduce the requirement for the AC source and guarantee the interchangeableness. Meanwhile, it is recommended that making the potential of one terminal of a simulated inductor stable is beneficial to the running stability. Furthermore, this work indirectly verifies the possibility and feasibility of the miniaturization of the C(4)D sensor by using the simulated inductor technique and lays a good foundation for future research work.

17.
Sensors (Basel) ; 14(12): 22431-46, 2014 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-25587879

RESUMEN

A capacitance measurement system is developed for the measurement of gas-liquid two-phase flow in glass micro-pipes with inner diameters of 3.96, 2.65 and 1.56 mm, respectively. As a typical flow regime in a micro-pipe two-phase flow system, slug flow is chosen for this investigation. A capacitance sensor is designed and a high-resolution and high-speed capacitance measurement circuit is used to measure the small capacitance signals based on the differential sampling method. The performance and feasibility of the capacitance method are investigated and discussed. The capacitance signal is analyzed, which can reflect the voidage variation of two-phase flow. The gas slug velocity is determined through a cross-correlation technique using two identical capacitance sensors. The simulation and experimental results show that the presented capacitance measurement system is successful. Research work also verifies that the capacitance sensor is an effective method for the measurement of gas liquid two-phase flow parameters in micro-pipes.

18.
Adv Sci (Weinh) ; 11(30): e2309785, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38889299

RESUMEN

Fusarium wilt (FW) is widespread in global cotton production, but the mechanism underlying FW resistance in superior-fiber-quality Sea Island cotton is unclear. This study reveals that FW resistance has been the target of genetic improvement of Sea Island cotton in China since the 2010s. The key nonsynonymous single nucleotide polymorphism (SNP, T/C) of gene Gbar_D03G001670 encoding protein phosphatase 2C 80 (PP2C80) results in an amino acid shift (L/S), which is significantly associated with FW resistance of Sea Island cotton. Silencing GbPP2C80 increases FW resistance in Sea Island cotton, whereas overexpressing GbPP2C80 reduces FW resistance in Arabidopsis. GbPP2C80 and GbWAKL14 exist synergistically in Sea Island cotton accessions with haplotype forms "susceptible-susceptible" (TA) and "resistant-resistant" (CC), and interact with each other. CRISPR/Cas9-mediated knockout of GbWAKL14 enhances FW and Verticillium wilt (VW) resistance in upland cotton and overexpression of GbWAKL14 and GbPP2C80 weakens FW and VW resistance in Arabidopsis. GbPP2C80 and GbWAKL14 respond to FW and VW by modulating reactive oxygen species (ROS) content via affecting MPK3 expression. In summary, two tandem genes on chromosome D03, GbPP2C80, and GbWAKL14, functions as cooperative negative regulators in cotton wilt disease defense, providing novel genetic resources and molecular markers for the development of resistant cotton cultivars.


Asunto(s)
Resistencia a la Enfermedad , Fusarium , Gossypium , Enfermedades de las Plantas , Especies Reactivas de Oxígeno , Verticillium , Gossypium/genética , Gossypium/microbiología , Gossypium/metabolismo , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Fusarium/genética , Resistencia a la Enfermedad/genética , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/genética , China , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Arabidopsis/genética , Arabidopsis/microbiología , Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo
19.
J Integr Med ; 22(2): 163-179, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38519277

RESUMEN

BACKGROUND: Ginkgo biloba L. preparations (GBLPs) are a class of Chinese herbal medicine used in the adjuvant treatment of ischemic stroke (IS). Recently, several systematic reviews (SRs) and meta-analyses (MAs) of GBLPs for IS have been published. OBJECTIVE: This overview aims to assess the quality of related SRs and MAs. SEARCH STRATEGY: PubMed, Embase, Cochrane Library, Web of Science, Chinese Biological Medicine, China National Knowledge Infrastructure, Wanfang, and Chinese Science and Technology Journals databases were searched from their inception to December 31, 2022. INCLUSION CRITERIA: SRs and MAs of randomized controlled trials (RCTs) that explored the efficacy of GBLPs for patients with IS were included. DATA EXTRACTION AND ANALYSIS: Two independent reviewers extracted data and assessed the methodological quality, risk of bias (ROB), reporting quality, and credibility of evidence of the included SRs and MAs using A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2), Risk of Bias in Systematic Reviews (ROBIS), the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA), and the Grading of Recommendations Assessment, Development and Evaluation (GRADE), respectively. Additionally, descriptive analysis and data synthesis were conducted. RESULTS: Twenty-nine SRs/MAs involving 119 outcomes were included in this review. The overall methodological quality of all SRs/MAs was critically low based on AMSTAR 2, and 28 had a high ROB based on the ROBIS. According to the PRISMA statement, the reporting items of the included SRs/MAs are relatively complete. The results based on GRADE showed that of the 119 outcomes, 8 were rated as moderate quality, 24 as low quality, and 87 as very low quality. Based on the data synthesis, GBLPs used in conjunction with conventional treatment were superior to conventional treatment alone for decreasing neurological function scores. CONCLUSION: GBLPs can be considered a beneficial supplemental therapy for IS. However, because of the low quality of the existing evidence, high-quality RCTs and SRs/MAs are warranted to further evaluate the benefits of GBLPs for treating IS. Please cite this article as: Meng TT, You YP, Li M, Guo JB, Song XB, Ding JY, Xie XL, Li AQ, Li SJ, Yin XJ, Wang P, Wang Z, Wang BL, He QY. Chinese herbal medicine Ginkgo biloba L. preparations for ischemic stroke: An overview of systematic reviews and meta-analyses. J Integr Med. 2024;22(2): 163-179.


Asunto(s)
Medicamentos Herbarios Chinos , Ginkgo biloba , Accidente Cerebrovascular Isquémico , Revisiones Sistemáticas como Asunto , Humanos , Medicamentos Herbarios Chinos/uso terapéutico , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Metaanálisis como Asunto , Fitoterapia , Ensayos Clínicos Controlados Aleatorios como Asunto , Extractos Vegetales/uso terapéutico , Extracto de Ginkgo
20.
Sensors (Basel) ; 13(2): 1563-77, 2013 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-23353139

RESUMEN

Combining the Capacitively Coupled Contactless Conductivity Detection (C4D) technique and the principle of cross correlation flow measurement, a new method for flow rate measurement in millimeter-scale pipes was proposed. The research work included two parts. First, a new five-electrode C4D sensor was developed. Second, with two conductivity signals obtained by the developed sensor, the flow rate measurement was implemented by using the principle of cross correlation flow measurement. The experimental results showed that the proposed flow rate measurement method was effective, the developed five-electrode C4D sensor was successful, and the measurement accuracy was satisfactory. In five millimeter-scale pipes with different inner diameters of 0.5, 0.8, 1.8, 3.0 and 3.9 mm respectively, the maximum relative difference of the flow rate measurement between the reference flow rate and the measured flow rate was less than 5%.

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