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  1. Article ; Online: Response of a Mesoscale Dipole Eddy to the Passage of a Tropical Cyclone

    Xiaorong Huang / Guihua Wang

    Remote Sensing, Vol 14, Iss 2865, p

    A Case Study Using Satellite Observations and Numerical Modeling

    2022  Volume 2865

    Abstract: Mesoscale eddies occurring in the world’s oceans typically exist in pairs known as mesoscale dipole eddies or simply dipole eddies. Tropical cyclones (hereafter TCs) that move over the world’s oceans often encounter and interact with these dipole eddies. ...

    Abstract Mesoscale eddies occurring in the world’s oceans typically exist in pairs known as mesoscale dipole eddies or simply dipole eddies. Tropical cyclones (hereafter TCs) that move over the world’s oceans often encounter and interact with these dipole eddies. Through this interaction, TCs induce significant perturbations in the mesoscale eddies. However, the specific influences that the passage of a TC on a dipole eddy have not been addressed. In this paper, a case study of the dipole eddy’s response to the passage of a TC is conducted by using satellite observations and numerical simulation. The passage of a TC induces a long-duration response in the dipole eddy. First, the cyclonic ocean eddy component (COE) of the dipole is amplified, and the anticyclonic ocean eddy component (AOE) is weakened or even destroyed during the interaction. The amplification of the COE and weakening of the AOE primarily manifests as a change in their amplitudes and radii and as the adjustment of their vertical structure. The dipole eddy’s response to the interaction with a TC manifests as an upwelling anomaly and the injection of positive relative vorticity. Following the passage of the TC, the COE gradually stabilizes, and AOE slowly recovers after the disturbance energy from the interaction dissipates, which facilitates the reestablishment of the dipole eddy. The dipole reaches an equilibrium state through a quasi-geostrophic adjustment process. As a consequence, the overall effect of the interaction of the dipole with the TC leads to an asymmetric signature on the dipole eddy. The eddy–eddy interaction in a dipole may allow it to stabilize in a shorter time relative to that of a solitary eddy.
    Keywords tropical cyclone ; mesoscale dipole eddy ; dynamic response ; satellite data ; numerical model ; Science ; Q
    Subject code 551
    Language English
    Publishing date 2022-06-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Citations and the Nature of Cited Sources

    Guihua Wang / Guangwei Hu

    SAGE Open, Vol

    A Cross-Disciplinary and Cross-Linguistic Study

    2022  Volume 12

    Abstract: Extant scholarship on citation has examined a limited number of citational features, adopted disciplinary and ethnolinguistic perspectives disjunctively, and paid little systematic attention to the nature of cited sources. Drawing on appraisal theory, ... ...

    Abstract Extant scholarship on citation has examined a limited number of citational features, adopted disciplinary and ethnolinguistic perspectives disjunctively, and paid little systematic attention to the nature of cited sources. Drawing on appraisal theory, the present study investigated the nature of cited sources, namely personalization (i.e., whether humans are foregrounded as a cited source) and identification (i.e., whether and how the cited sources are identified), to understand their dialogic functionality in knowledge making. We analyzed citations in a corpus of 84 research articles sampled from two disciplines and two languages. Greater citation-based dialogic contraction was found in the medical articles than in the applied linguistic articles, whereas the cross-linguistic contrasts revealed a mixed picture. The differences are explained in terms of divergent epistemologies, cultural beliefs, discursive practices, institutional settings, and co-patterning of different citation features.
    Keywords History of scholarship and learning. The humanities ; AZ20-999 ; Social Sciences ; H
    Subject code 001
    Language English
    Publishing date 2022-04-01T00:00:00Z
    Publisher SAGE Publishing
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: Response of Soil Available Nitrogen Spatial Variability to Sampling Spacing in Maize Propagation Base

    Bingsun WU / Yong SUN / Guihua WANG / Jingjing WANG

    Guangdong nongye kexue, Vol 50, Iss 4, Pp 66-

    2023  Volume 74

    Abstract: Objective】The spatial variability and scale effect of soil available nitrogen content in maize propagation base were investigated, and reasonable sampling interval was determined to provide a theoretical basis for accurate soil sampling design.【Method】 ... ...

    Abstract 【Objective】The spatial variability and scale effect of soil available nitrogen content in maize propagation base were investigated, and reasonable sampling interval was determined to provide a theoretical basis for accurate soil sampling design.【Method】Taking the perennial southern maize propagation plot as the test plot, soil samples were collected at 10 m sampling interval with original scale, and sampled successively at 20, 30 and 40 m to form different sampling interval data sets. Spatial autocorrelation Moran index, semi-variogram and fractal dimension were used to analyze the spatial structure changes of soil available nitrogen content under different sampling interval conditions.【Result】The average content of soil available nitrogen in the test site was 90.24 mg/kg, belonging to the medium level, and the coefficient of variation was 19.77%, belonging to the medium range of variation. At the sampling intervals of 10, 20, 30 and 40 m, the data structure of soil available nitrogen samples did not change notably, only the coefficient of variation was different greatly. The coefficient of variation at the sampling interval of 20 m was the largest 29.37 %, while that at the other sampling intervals was little different. With the increase of sampling interval, the spatial autocorrelation Moran index of soil available nitrogen content decreased and its spatial aggregation became weaker, while the nugget value, block base ratio and fractal dimension showed an increasing trend, indicating that the spatial variation caused by random factors gradually increased, while the spatial variation caused by random factors gradually weakened the spatial variation caused by structural factors, making the spatial correlation gradually weakened. The spatial distribution of soil available nitrogen content with a 20 m sampling interval was consistent with the original scale of a 10 m sampling interval, and the root mean square error value of spatial prediction was the smallest, indicating that the spatial prediction accuracy was ...
    Keywords maize propagation base ; soil available nitrogen ; spatial variability ; sampling spacing ; spatial autocorrelation ; scale effect ; Agriculture ; S
    Subject code 550
    Language English
    Publishing date 2023-04-01T00:00:00Z
    Publisher Guangdong Academy of Agricultural Sciences
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article ; Online: The influence of cold filaments on the evolution of dipole structures

    Qi Yang / Guihua Wang / Chi Xu / Guoping Gao / Ruili Sun

    Frontiers in Marine Science, Vol

    2023  Volume 10

    Abstract: Mesoscale eddy dipoles are oceanographic structures that can transport ocean water parcels horizontally and vertically in ways that differ from individual mesoscale eddies. The most conspicuous additional feature that presents in dipoles is the cold ... ...

    Abstract Mesoscale eddy dipoles are oceanographic structures that can transport ocean water parcels horizontally and vertically in ways that differ from individual mesoscale eddies. The most conspicuous additional feature that presents in dipoles is the cold filament (CF) that can be spontaneously generated between a dipole’s anticyclonic eddy (AE) and cyclonic eddy (CE). A case study in this paper shows that the interaction between the CF and the CE component of the dipole is associated with the structural evolution of the dipole. This interaction is verified in synthesis and normalization studies of the CF dipoles. The CF-dipole interaction entrains CF water into the center of the dipole’ CE and leads to a cold and high chlorophyll center in the upper layer of the CE. The formation of this cold center changes the dipole’s structure by eliminating the phase difference between the thermal and dynamic centers of the dipole. The entrainment also provides a new mechanism for the development of high chlorophyll levels in the CE. In the analysis of the HYCOM (Hybrid Coordinate Ocean Model) simulation of a synthetic CF dipole, the AE has a three-zone structure while the CE only has two. The convergence of the CE’s outermost zone results in a biased interaction.
    Keywords filament ; mesoscale eddy dipole ; interaction ; structure ; Lagrangian trajectory ; chlorophyll ; Science ; Q ; General. Including nature conservation ; geographical distribution ; QH1-199.5
    Subject code 551
    Language English
    Publishing date 2023-06-01T00:00:00Z
    Publisher Frontiers Media S.A.
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: Hydrological Evaluation of Satellite-Based Precipitation Products in Hunan Province

    Yan Yan / Guihua Wang / Nergui Nanding / Weitian Chen

    Remote Sensing, Vol 14, Iss 3127, p

    2022  Volume 3127

    Abstract: The quality of satellite-based precipitation products including TMPA 3B42, IMERG-early, IMERG-final, and CMORPH-CRT, is evaluated by comparing with gauge observations in Hunan province of China between 2017 and 2019. By using the outputs of the Dominant ... ...

    Abstract The quality of satellite-based precipitation products including TMPA 3B42, IMERG-early, IMERG-final, and CMORPH-CRT, is evaluated by comparing with gauge observations in Hunan province of China between 2017 and 2019. By using the outputs of the Dominant River Routing Integrated with VIC Environment (DRIVE) model, the hydrological applications of gauge- and satellite-based precipitation products are analyzed by comparing them with streamflow observations. Furthermore, we conduct a case study considering Typhoon Bailu. It is found that IMERG-final can produce better results compared to the other three satellite-based products against gauge-based precipitation. In terms of discharge simulations, the gauge-based precipitation provides the most accurate results, followed by IMERG-final. During Typhoon Bailu, the peak of the mean gauge-based precipitation in the rainfall center (24.5°N–26°N, 111°E–114°E) occurred on 25 August 2019, whereas the daily streamflow reached its peak one day later, suggesting the lagged impact of precipitation on streamflow. From the Taylor diagram, the gauge-based precipitation is the most accurate for estimating the streamflow during Typhoon Bailu, followed by IMERG-final, IMERG-early, TMPA 3B42, and CMORPH-CRT, respectively. Overall, gauge-based precipitation has the best performance in terms of hydrological application, whereas IMERG-final performs the best among four satellite-based precipitation products.
    Keywords satellite-based precipitation ; discharge simulations ; Typhoon Bailu ; Science ; Q
    Subject code 910
    Language English
    Publishing date 2022-06-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: Exploring the Mechanism of Ionic Liquids to Improve the Extraction Efficiency of Essential Oils Based on Density Functional Theory and Molecular Dynamics Simulation

    Xiaorong Luo / Fen Wang / Guihua Wang / Hui Li

    Molecules, Vol 27, Iss 5515, p

    2022  Volume 5515

    Abstract: In this paper, Amomi fructus (Latin) was used to explore the mechanism of ionic liquids (ILs) in improving the extraction efficiency of essential oils. Microwave assisted ionic liquid treatment followed by a hydro-distillation (MILT-HD) process for ... ...

    Abstract In this paper, Amomi fructus (Latin) was used to explore the mechanism of ionic liquids (ILs) in improving the extraction efficiency of essential oils. Microwave assisted ionic liquid treatment followed by a hydro-distillation (MILT-HD) process for isolating Amomi fructus essential oil was optimized by multi-objective optimization. Under optimum operating conditions, the IL-assisted extraction method not only enhances extraction efficiency but also reduces energy demands and CO 2 emissions. Since the hydrogen bond structure network of cellulose in the cell wall is an important reason for hindering diffusion of essential oils, the mechanism of ILs was explored by density functional theoretical (DFT) and molecular dynamics (MD) simulations. According to DFT calculations, ILs can facilitate the cleavage of cellulose chains and have strong non-covalent interactions with cellulose. Based on the MD simulations, the degree of destruction of the cellulose hydrogen bond structure was explored. According to the DFT and MD simulations, the ILs can significantly destroy cellulose structure, thereby promoting essential oil release from the plant. These results were confirmed by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). This work is conducive to better understand the MILT-HD process for isolating essential oil and comprehensively understand the mechanism of ILs in the extraction process.
    Keywords essential oil ; ionic liquids ; multivariate analysis ; density functional theory ; molecular dynamics simulations ; Organic chemistry ; QD241-441
    Subject code 660
    Language English
    Publishing date 2022-08-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Article ; Online: Observed Warm Filaments from the Kuroshio Associated with Mesoscale Eddies

    Qian Shi / Guihua Wang

    Remote Sensing, Vol 12, Iss 3090, p

    2020  Volume 3090

    Abstract: Based on high resolution satellite observations of sea surface temperature (SST), warm filaments near the Kuroshio around the Luzon Strait were systematically identified. These filaments extend an average length of about 200 km from the Kuroshio. The ... ...

    Abstract Based on high resolution satellite observations of sea surface temperature (SST), warm filaments near the Kuroshio around the Luzon Strait were systematically identified. These filaments extend an average length of about 200 km from the Kuroshio. The occurrence and features of the warm filaments are highly associated with both mesoscale eddies and the intensity of the SST gradient of the Kuroshio. Warm filaments are formed by heat advection from the warm Kuroshio into the colder interior Pacific Ocean by anticyclonic eddies (∼58%), cyclonic eddies (∼10%), and the dipole eddies (∼16%). The large temperature gradient near the Batanes Islands may also contribute to the high frequency of warm filaments in their vicinity. This study will help elucidate the role of zonal heat transport associated with the Kuroshio–eddy interaction during filament formation.
    Keywords warm filaments ; Kuroshio–eddy interaction ; warm tongues ; Science ; Q
    Subject code 551
    Language English
    Publishing date 2020-09-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: Impact of socioeconomic status on cancer staging, survival in non-small cell lung cancer

    Xianghui Yang / Liyong Deng / Min Li / Yongjie Zhou / Guihua Wang

    Frontiers in Public Health, Vol

    2022  Volume 10

    Abstract: PurposeWe performed this study to evaluate the association of socioeconomic status (SES) factors with cancer-specific survival (CSS) of patients with non-small cell lung cancer (NSCLC). We further assessed the predictive value of a novel Tumor Node ... ...

    Abstract PurposeWe performed this study to evaluate the association of socioeconomic status (SES) factors with cancer-specific survival (CSS) of patients with non-small cell lung cancer (NSCLC). We further assessed the predictive value of a novel Tumor Node Metastasis (TNM)-SES staging system, combining the TNM stage with the SES stage.MethodsUsing the Surveillance, Epidemiology, and End Results (SEER) database, we selected 40,378 patients diagnosed with NSCLC from 2012 to 2016. Cox regression method and Harrell's concordance index (C-index) were performed to select the SES factors related to CSS and evaluate the predictive ability of the novel TNM-SES stage. We used Kaplan–Meier curves and a log-rank test to conduct a survival analysis.ResultsWe identified four SES factors (marriage, insurance, education, and household income) associated with CSS and constructed the SES stage (SES-1 and SES-2). NSCLC patients with SES-2 stage (low SES) was associated with young adult, black race, male, squamous carcinoma, upper lobe site, and advanced stage. SES-2 stage patients were significantly associated with a dismal prognosis of patients with NSCLC, with a 21.0% increased risk (HR = 1.21, 95%CI (1.18–1.24), p < 0.001). The C-index of our novel TNM-SES stage was 0.732 [95% CI (0.728–0.736)], higher than the traditional TNM stage [0.717, 95% CI (0.715–0.719)], indicating superior predictive value.ConclusionOur population-based study indicated that SES was significantly associated with cancer staging and SCC in patients with NSCLC. Our novel TNM-SES staging system showed a superior predictive value to the traditional TNM stage. The impact of SES on patients with NSCLC should receive more concern in clinical management.
    Keywords TNM stage ; non-small cell lung cancer ; SEER database ; socioeconomic status ; prognosis ; Public aspects of medicine ; RA1-1270
    Subject code 610 ; 616
    Language English
    Publishing date 2022-11-01T00:00:00Z
    Publisher Frontiers Media S.A.
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article ; Online: Characteristics of Precipitation and Floods during Typhoons in Guangdong Province

    Yan Yan / Guihua Wang / Huan Wu / Guojun Gu / Nergui Nanding

    Remote Sensing, Vol 14, Iss 1945, p

    2022  Volume 1945

    Abstract: The spatial and temporal characteristics of precipitation and floods during typhoons in Guangdong province were examined by using TRMM TMPA 3B42 precipitation data and the Dominant River Routing Integrated with VIC Environment (DRIVE) model outputs for ... ...

    Abstract The spatial and temporal characteristics of precipitation and floods during typhoons in Guangdong province were examined by using TRMM TMPA 3B42 precipitation data and the Dominant River Routing Integrated with VIC Environment (DRIVE) model outputs for the period 1998–2019. The evaluations based on gauge-measured and model-simulated streamflow show the reliability of the DRIVE model. The typhoon tracks are divided into five categories for those that landed on or influenced Guangdong province. Generally, the spatial distribution of precipitation and floods differ for different typhoon tracks. Precipitation has a similar spatial distribution to flood duration (FD) but is substantially different from flood intensity (FI). The average precipitation over Guangdong province usually reaches its peak at the landing time of typhoons, while the average FD and FI reach their peaks several hours later than precipitation peak. The lagged correlations between precipitation and FD/FI are hence always higher than their simultaneous correlations.
    Keywords typhoon ; flood ; precipitation ; Science ; Q
    Subject code 910
    Language English
    Publishing date 2022-04-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  10. Article ; Online: Automatically Extracting Rubber Tree Stem Shape from Point Cloud Data Acquisition Using a B-Spline Fitting Program

    Tuyu Li / Yong Zheng / Chang Huang / Jianhua Cao / Lingling Wang / Guihua Wang

    Forests, Vol 14, Iss 1122, p

    2023  Volume 1122

    Abstract: Natural rubber is an important and strategic raw material, used in tires, gloves, and insulating products, that is mainly obtained by cutting the bark of rubber trees. However, the complex contour curve of the rubber tree trunk is hard to fit using a ... ...

    Abstract Natural rubber is an important and strategic raw material, used in tires, gloves, and insulating products, that is mainly obtained by cutting the bark of rubber trees. However, the complex contour curve of the rubber tree trunk is hard to fit using a tapping machine. Thus, a trunk contour curve collection would be useful for the development of tapping machines. In this study, an acquisition system based on laser-ranging technology was proposed to collect the point cloud data of rubber tree trunks, and a B-spline fitting program was compiled in Matrix Laboratory (MATLAB) to extract the trunks’ contour curves. The acquisition system is composed of power, a controller, a driver, a laser range finder, and data transmission modules. An automatic extraction experiment on the contour curves of rubber tree trunks was carried out to verify the feasibility and accuracy of using the acquisition system. The results showed that the degree of rubber tree trunk characteristic recognition reached 94.67%, which means that the successful extraction of the rubber tree trunk contour curves and the B-spline fitting program are suitable for the extraction of irregular curves of rubber tree trunks. The coefficient of variation of repeated collection was 0.04%, which indicates that changes in relative positions and acquisition directions have little influence on the extraction and the accuracy of the acquisition system, which are high and stable. Therefore, it was unnecessary to adjust the position of the acquisition device before the collecting process, which helped to improve the efficiency of acquisition considerably. The acquisition system proposed in this study is meaningful to the practical production and application of agroforestry and can not only improve the precision of the rubber tapping process by combining with an automatic rubber tapping machine but can also provide technical support for the prediction of rubber wood volume and the development of ring-cutting equipment for other fruit trees.
    Keywords rubber tree ; laser-ranging ; point cloud data ; contour curve ; B-spline ; MATLAB ; Plant ecology ; QK900-989
    Subject code 670
    Language English
    Publishing date 2023-05-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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