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1.
Opt Lett ; 49(7): 1713-1716, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38560844

RESUMO

Hard x-rays are widely used for plasma diagnosis, nondestructive inspection, and high-resolution x-ray imaging. A typical x-ray source is a tabletop micro-focus x-ray source. Here, a bifocal photon sieve (PS) with the smallest diameter of 59.6 nm was designed and fabricated by electron-beam lithography to focus hard x-rays on variable-resolution array images. An imaging experiment at 8.39 keV demonstrates that the designed and fabricated PS has two different focal lengths. The numerous pinholes that can be optimized provide richer degrees of freedom to realize considerably more functionalities. A multi-focal PS provides the possibility of splitting x-rays and further extends interferometry from visible light to hard x-rays.

2.
Appl Opt ; 63(4): 1105-1109, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38437409

RESUMO

The traditional interferometric calibration of phase spatial light modulators (SLM) based on interference fringes shift is easily disturbed due to environmental vibration. Here a kind of absolutely interferometric calibration of phase SLM is investigated to eliminate the disturbance using dual honeycomb gratings composited with Billet-split Fresnel zone plates (BsFZP), in which honeycomb gratings split an incident beam into three beams and the first two beams are interfered by BsFZP while the last beam is chosen as the absolute reference point. The experiments on both 532 and 632.8 nm incident wavelengths were separately carried out, and the measuring accuracy was proved by a SID4 wavefront sensor. The proposed high-accuracy calibration provided the basis for SLM application scenarios with high precision.

3.
BMC Public Health ; 24(1): 1023, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609890

RESUMO

OBJECTIVE: The study aims to examine how moderate-to-vigorous physical activity (MVPA) affects the severity of depression symptoms among Chinese college students. Additionally, it seeks to analyze the mediating mechanisms involving self-rated health and general self-efficacy. METHODS: The study utilized data from the 2023 Chinese College Health Tracking Survey and employed multiple linear regression and structural equation modeling techniques to investigate the impacts of MVPA on depression levels and its underlying mediating mechanisms among college students. The primary cohort comprised 49,717 enrolled college students from 106 universities in China. RESULTS: A total of 41,620 valid questionnaires were collected (response rate: 83.7%), with females accounting for 58.6%. In the past month, approximately 30.2% of college students engaged in MVPA. Self-rated health (B = - 0.282, P < 0.001) and general self-efficacy (B = - 0.133, P < 0.001) significantly influenced college students' depression scores. Even after controlling for other variables, participating in MVPA remained significantly associated with reduced depression scores (B = - 0.062, P = 0.002). The results of the structural equation model showed that MVPA not only directly decreased college students' depression scores but also indirectly reduced the likelihood of depression occurrence by improving their physical health status and general self-efficacy. CONCLUSION: The lack of physical activity among Chinese college students is evident. Engaging in MVPA can reduce the likelihood of depression among college students. MVPA achieves this reduction by enhancing college students' general self-efficacy and improving their physical health. The factors influencing depression levels among college students are multifaceted. For future interventions targeting college students' mental health, comprehensive approaches that incorporate behavioral and psychological factors should be emphasized.


Assuntos
Depressão , Exercício Físico , Feminino , Humanos , Depressão/epidemiologia , Universidades , Inquéritos Epidemiológicos , Estudantes
4.
Opt Lett ; 48(16): 4276-4279, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37582011

RESUMO

Diffractive lenses are popular in large optical systems owing to their lightweight and multifunctional design. However, they are difficult to calibrate accurately due to the cross talk between the first-order diffraction and the background light. Here, a quadriwave lateral shearing interferometry (QWLSI) with spherical wave illumination was proposed to absolutely measure the focusing properties of diffractive lenses by means of the reference background light, in which the corresponding theoretical modeling was first derived, and then the single-shot experiment on a 210 mm-diameter beam was carried out. The results showed that the measurement error of the focal length was 0.59%, and the consistency error was 0.008%.

5.
BMC Cancer ; 23(1): 864, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37704946

RESUMO

Clear cell renal cell carcinoma (CCRCC) is a common tumor of the urological system for which surgery is the preferred treatment, but there is a lack of therapeutic options after surgery. This study aims to explore the biological role of GNG7 on CCRCC from a genetic perspective. Differences in mRNA expression and patient survival of GNG7 in patients with CCRCC and healthy patients were analyzed using the TCGA database. It was observed that GNG7 gene expression was downregulated in CCRCC tissue compared with healthy tissue, and high GNG7 predicted better prognosis for patients, and GNG7 also showed strong variability in clinical and TMN staging. The immune relevance of GNG7 and related genes was explored using renal cancer data from CCLE and TISIDB database. It was verified that the risk score constructed by 7 GNG7-related regulators might be used as an independent prognostic risk factor for CCRCC. A CCRCC prognostic model that involved 7 immune genes was further established to predict the survival probabilities of patients. At last, the GEO database and immunochemical tissue staining were used to validate GNG7 expression in CCRCC. Our study proposed a novel panel of genes to predict CCRCC OS based on GNG7-related immune genes, which may help to accurately predict the prognosis of CCRCC patients and make better clinical decisions for individual treatment.


Assuntos
Carcinoma de Células Renais , Carcinoma , Neoplasias Renais , Humanos , Carcinoma de Células Renais/genética , Prognóstico , Fatores Imunológicos , Adjuvantes Imunológicos , Neoplasias Renais/genética , Fatores de Risco
6.
BMC Urol ; 23(1): 82, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37138262

RESUMO

BACKGROUND: Clear cell renal cell carcinoma (ccRCC) is one of the most common malignancies. Recently, immunotherapy has been considered a promising treatment for metastatic ccRCC. NUF2 is a crucial component of the Ndc80 complex. NUF2 can stabilize microtubule attachment and is closely related to cell apoptosis and proliferation. This research is dedicated to investigating the role of NUF2 in ccRCC and the possible mechanisms. METHODS: First, analysis of NUF2 mRNA expression levels in ccRCC and normal tissues by The Cancer Genome Atlas (TCGA) database and further verified by analysis of independent multiple microarray data sets in the Gene Expression Omnibus (GEO) database. Moreover, we evaluated and identified correlations between NUF2 expression, clinicopathologic variable, and overall survival (OS) in ccRCC by various methods. We investigated the relationship between NUF2 and tumor immune infiltration and the expression of corresponding immune cell markers via the Gene Expression Profiling Interactive Analysis (GEPIA) and Tumor Immune Estimation Resource (TIMER) databases. Then, we performed functional enrichment analysis of NUF2 co-expressed genes using R software and protein-protein interactions (PPIs) using the search tool used to retrieve interacting genes/proteins (STRING) databases. RESULTS: We discovered that NUF2 mRNA expression was upregulated in ccRCC tissues and was associated with sex, grade, pathological stage, lymph node metastasis, and worse prognosis. In addition, NUF2 was positively linked to tumor immune cells in ccRCC. Moreover, NUF2 was closely related to genetic markers of different immune cells. Finally, functional enrichment and protein-protein interaction (PPI) analysis suggested that NUF2 and its closely related genes may be involved in the regulation of the cell cycle and mitosis. Our results suggested that NUF2 is correlated with a poor prognosis and immune infiltration in ccRCC.


Assuntos
Biomarcadores Tumorais , Carcinoma de Células Renais , Carcinoma , Proteínas de Ciclo Celular , Neoplasias Renais , Humanos , Apoptose/genética , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/patologia , Bases de Dados Genéticas , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Neoplasias Renais/genética , Neoplasias Renais/imunologia , Neoplasias Renais/patologia , Prognóstico
7.
BMC Urol ; 23(1): 162, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37828486

RESUMO

BACKGROUND: Existing epidemiological observational studies have suggested interesting but inconsistent clinical correlations between inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), and kidney stone disease (KSD). Herein, we implemented a two-sample bidirectional Mendelian randomization (MR) to investigate the causal relationship between IBD and KSD. METHODS: Data on IBD and KSD were obtained from Genome-Wide Association Studies (GWAS) summary statistics and the FinnGen consortium, respectively. Strict selection steps were used to screen for eligible instrumental SNPs. We applied inverse variance weighting (IVW) with the fix-effects model as the major method. Several sensitivity analyses were used to evaluate pleiotropy and heterogeneity. Causal relationships between IBD and KSD were explored in two opposite directions. Furthermore, we carried out multivariable MR (MVMR) to obtain the direct causal effects of IBD on KSD. RESULTS: Our results demonstrated that CD could increase the risk of KSD (IVW: OR = 1.06, 95% CI = 1.03-1.10, p < 0.001). Similar results were found in the validation group (IVW: OR = 1.05, 95% CI = 1.01-1.08, p = 0.013) and in the MVMR analysis. Meanwhile, no evidence of a causal association between UC and KSD was identified. The reverse MR analysis detected no causal association. CONCLUSIONS: This MR study verified that CD plays a critical role in developing kidney stones and that the effect of UC on KSD needs to be further explored.


Assuntos
Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Cálculos Renais , Humanos , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Cálculos Renais/epidemiologia , Cálculos Renais/genética , Colite Ulcerativa/complicações , Colite Ulcerativa/genética , Doença de Crohn/genética
8.
Opt Lett ; 47(3): 485-488, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35103657

RESUMO

Multi-wavelength diffraction imaging is a lensless, high-resolution imaging technology. To avoid multiple exposures and enable high-speed data collection, here an innovative setup for the single-exposure multi-wavelength diffraction imaging based on a blazed grating is proposed. Since the blazed angle varies with the wavelength, the diffraction patterns for the individual wavelengths can be separated from each other and recorded in a single measurement at one time. A method of high-precision position alignment between different wavelength patterns is proposed in our system to achieve good image quality and high resolution. Experiments on a phase-only USAF resolution target and biological samples were carried out to verify the effectiveness of our proposed method. This proposed setup has such advantages as a simpler structure, fast recording, and algorithm robustness.


Assuntos
Diagnóstico por Imagem
9.
Opt Lett ; 47(22): 5813-5816, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37219110

RESUMO

An exact modal decomposition method plays an important role in revealing the modal characteristics of a few-mode fiber, and it is widely used in various applications ranging from imaging to telecommunications. Here, ptychography technology is successfully used to achieve modal decomposition of a few-mode fiber. In our method, the complex amplitude information of the test fiber can be recovered by ptychography, and then the amplitude weight of each eigenmode and the relative phase between different eigenmodes can be easily calculated by modal orthogonal projection operations. In addition, we also propose a simple and effective method to realize coordinate alignment. Numerical simulations and optical experiments validate the reliability and feasibility of the approach.

10.
Macromol Rapid Commun ; 43(17): e2200156, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35482976

RESUMO

Single-chain polymer nanoparticles (SCNPs) are soft matter constructed by intrachain crosslinks, with promising prospects in detection and catalysis. Herein, a fluorescent core (SCNPs) with aggregation-induced emission (AIE) is prepared, applying for H2 O2 detection through intermolecular heavy-atom effect. In detail, the SCNPs precursors are synthesized by ring-opening copolymerization. Then the SCNPs are prepared by intramolecularly cross-linking via olefin metathesis. Imitating the structure of AIE dots, SCNPs are encapsulated by H2 O2 -responsive polymers. Probably due to the stable secondary structure of SCNPs, the obtained micelles show stable fluorescence performance. Furthermore, as the heavy-atom, tellurium is introduced into the carriers to construct the heavy-atom effect. In this micelle-based system, the SCNPs act as the fluorescent core, and the stimuli-responsive polymer acts as the carrier and the fluorescent switch. The hydrophilicity of the tellurium-containing segment is affected by the concentration of H2 O2 , resulting in a change in the distance from the SCNPs, which ultimately leads to a change in the fluorescence intensity. Furthermore, tellurium is particularly sensitive to H2 O2 , which can detect low concentrations of H2 O2 . The SCNPs are merged with AIE materials, with the hope of exploring new probe designs.


Assuntos
Nanopartículas , Polímeros , Micelas , Nanopartículas/química , Polimerização , Polímeros/química , Telúrio
11.
Appl Opt ; 61(26): 7685-7691, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36256369

RESUMO

A vortex array has important applications in scenarios where multiple vortex elements with the same or different topological charges are required simultaneously. Therefore, the detection of the vortex array is vital. Here, the interferogram between the off-axis Walsh-phase plate and the vortex array is first obtained and then decoded through a convolution neural network (CNN), which can simultaneously determine the topological charge, chirality, and the initial angle. Both the theory and experiment prove that a CNN has a remarkable effect on the classification and detection of vortex arrays.


Assuntos
Redes Neurais de Computação
12.
Opt Express ; 29(5): 7197-7209, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33726225

RESUMO

Multi-wavelength imaging diffraction system is a promising phase imaging technology due to its advantages of no mechanical movement and low complexity. In a multi-wavelength focused system, spectral bandwidth and dispersion correction are critical for high resolution reconstruction. Here, an optical setup for the multi-wavelength lensless diffraction imaging system with adaptive dispersion correction is proposed. Three beams with different wavelengths are adopted to illuminate the test object, and then the diffraction patterns are recorded by a image sensor. The chromatic correction is successfully realized by a robust refocusing technique. High-resolution images can be finally retrieved through phase retrieval algorithm. The effectiveness and reliability of our method is demonstrated in numerical simulation and experiments. The proposed method has the potential to be an alternative technology for quantitative biological imaging.

13.
BMC Cancer ; 21(1): 556, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34001040

RESUMO

BACKGROUND: The platelet-to-lymphocyte ratio (PLR) and C-reactive protein (CRP) level are markers that have been reported to predict the histological type of various tumors, and here, we evaluated their utility in predicting colorectal polyp histological types. METHODS: We retrospectively reviewed 172 patients with colorectal polyps who underwent endoscopic polypectomy. The associations between histological type and clinicopathologic parameters were assessed by multivariate analysis. RESULTS: The optimal PLR and CRP cut-off values were 113.32 and 0.39, respectively. The PLR (P = 0.002) and CRP (P = 0.009) values were associated with the histological type according to the univariate analysis, whereas low PLR (P ≤ 0.001) and CRP (P = 0.017) values were independent risk factors in the multivariate analysis together with maximum tumor diameter (P ≤ 0.001) and tumor number (P = 0.0014). CONCLUSIONS: Preoperative PLR and CRP are correlated with the colorectal polyp histological type.


Assuntos
Biomarcadores Tumorais/sangue , Pólipos do Colo/diagnóstico , Neoplasias Colorretais/diagnóstico , Adulto , Idoso , Plaquetas , Proteína C-Reativa/análise , Colo/patologia , Colo/cirurgia , Pólipos do Colo/sangue , Pólipos do Colo/patologia , Pólipos do Colo/cirurgia , Colonoscopia , Neoplasias Colorretais/sangue , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Mucosa Intestinal/patologia , Mucosa Intestinal/cirurgia , Contagem de Linfócitos , Linfócitos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Prognóstico , Reto do Abdome/patologia , Reto do Abdome/cirurgia , Estudos Retrospectivos
14.
BMC Urol ; 20(1): 107, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32689976

RESUMO

BACKGROUND: Primary squamous cell carcinoma of the renal parenchyma is extremely rare, only 5 cases were reported. CASE PRESENTATION: We probably report the fifth case of primary Squamous cell carcinoma (SCC) of the renal parenchyma in a 61-year-old female presenting with intermittent distending pain for 2 months. Contrast-enhanced computed tomography (CECT) revealed hydronephrosis of the right kidney, but a tumor cannot be excluded completely. Finally, nephrectomy was performed, and histological analysis determined that the diagnosis was kidney parenchyma squamous cell carcinoma involving perinephric adipose tissue. CONCLUSIONS: The present case emphasizes that it is difficult to make an accurate preoperative diagnosis with the presentation of hidden malignancy, such as hydronephrosis.


Assuntos
Carcinoma de Células Escamosas/complicações , Hidronefrose/etiologia , Neoplasias Renais/complicações , Feminino , Humanos , Pessoa de Meia-Idade , Tecido Parenquimatoso
15.
Appl Opt ; 59(14): 4314-4320, 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32400407

RESUMO

Phase defect detection with micrometer scale on large aperture optical elements is one of the challenges in precision optical systems. An efficient scheme is proposed to detect phase defects. First, the defects are positioned in a large aperture by dark-field imaging based on large aperture photon sieves to improve the detection efficiency with a relatively low cost. Second, static multiplanar coherent diffraction imaging is used to retrieve the phase of the positioned defects in a small field of view. Here, a spatial light modulator is used as a multifocal negative lens to eliminate the mechanical errors in multiplanar imaging. The use of a negative lens instead of a positive lens has the advantage of a larger imaging space for the system configuration. Compared to the traditional interferometry system, this diffraction detection system has a simpler optical path and doesn't require sparse distribution of the defects. Experiment results demonstrate the success of the proposed scheme with a detection resolution better than 50 µm. We believe this work provides an effective method to rapidly detect phase defects on large aperture optics with high accuracy and high resolution.

16.
Appl Opt ; 59(17): 5265-5268, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32543548

RESUMO

A method of radial-shearing interferometric imaging based on the Theon-Kepler bifocal telescope is proposed. The Theon-Kepler bifocal telescope system consists of two identical Theon photon sieves with bifocal spots. The short focal length of the first photon sieve coincides with the long focal length of the second photon sieve. At the same time, the first focal length coincides with the second short focal length. This setup naturally constitutes two sets of 4f systems. When a plane wave is incident on the bifocal telescope, two plane waves of different sizes are emitted. These two beams undergo radial-shearing interference. The common-path setup of this new type of radial-shearing interferometer is simple, with low requirements for the experimental environment and strong anti-interference ability.

17.
Urol Int ; 104(1-2): 142-147, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31851995

RESUMO

INTRODUCTION: To evaluate the potential predictive value of the Mayo Adhesive Probability (MAP) score combined with the RENAL score for intraoperative outcomes in retroperitoneal laparoscopic nephron-sparing surgery (NSS) in an Eastern Asian population. METHODS: An initial of 388 patients undergoing retroperitoneal laparoscopic NSS were identified. MAP and RENAL scores were calculated according to CT and a logistic regression model was adopted as a combination of the RENAL score and the MAP score. RESULTS: A total of 293 patients were included. The overall intraoperative complication rate was 7.5% (21 cases). The MAP score was found to correlate with operation time (OT; r = 0.169), estimated blood loss (EBL; r = 0.318), and intraoperative complications (r = 0.242). The RENAL score was correlated with warm is-chemia time (r = 0.503), OT (r = 0.334), intraoperative complications (r = 0.178), and EBL (r = 0.218). The MAP score and the RENAL score were reliable predictors of overall intraoperative complications, with areas under the curve (AUC) of 0.728 and 0.759, respectively. After combination of these 2 scores, the AUC of overall intra-operative complications was improved with statistical significance (AUC = 0.847, combination vs. RENAL score: p = 0.044 < 0.05; combination vs. MAP score: p = 0.005 < 0.05). CONCLUSION: The MAP score is an important predictor of EBL, OT, and intraoperative complications in retroperitoneal laparoscopic NSS and its combination with the RENAL score showed a superior predictive value compared to a single score in overall intraoperative complications. The MAP score might be considered in preoperative radiologic aspects as regularly as the RENAL score.


Assuntos
Tecido Adiposo/anatomia & histologia , Carcinoma de Células Renais/cirurgia , Complicações Intraoperatórias/diagnóstico , Neoplasias Renais/cirurgia , Rim/anatomia & histologia , Índice de Gravidade de Doença , Tecido Adiposo/patologia , Adulto , Idoso , Algoritmos , Área Sob a Curva , Índice de Massa Corporal , Feminino , Humanos , Rim/patologia , Laparoscopia , Masculino , Pessoa de Meia-Idade , Nefrectomia , Néfrons/cirurgia , Probabilidade , Análise de Regressão , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
18.
J Cell Biochem ; 120(6): 9594-9600, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30569513

RESUMO

Long noncoding RNA (lncRNA) LINC-PINT expression is inhibited in many types of cancer cells, suggesting its role as a tumor suppressor. However, the functionality of LINC-PINT in gastric cancer and the clinical values are unknown. In the present study, we found that lncRNA LINC-PINT was downregulated, while microRNA-21 (miR-21) was upregulated in tumor tissues than in adjacent healthy tissues of gastric cancer patients. A significant and inverse correlation between expression levels of lncRNA LINC-PINT and miR-21 was found in both tumor tissues and adjacent healthy tissues. The low expression level of LINC-PINT and high expression level of the miR-21 tumor were correlated with poor prognosis. LINC-PINT overexpression casued miR-21 inhibition in cells of human gastric cancer cell lines, while miR-21 overexpression did not alter LINC-PINT expression. LINC-PINT overexpression led to inhibited, while miR-21 overexpression led to promoted proliferation, migration, and invasion of gastric cancer cells. Effects of LINC-PINT overexpression on cellular behaviors of gastric cancer cells were attenuated by miR-21 overexpression. Therefore, LINC-PINT may participate in gastric cancer through the crosstalk with miR-21.


Assuntos
RNA Longo não Codificante/genética , Neoplasias Gástricas/genética , Adulto , Idoso , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , RNA Longo não Codificante/metabolismo , Neoplasias Gástricas/patologia , Análise de Sobrevida
19.
Opt Express ; 27(22): 32392-32397, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684453

RESUMO

Phase-shifting holography has been widely applied in the field of non-destructive testing and interference imaging. Compared to the previous single-shot phase-shifting holography, here tri-focal Fibonacci-Billet split lens was introduced into Mach-Zehnder interferometer, in which the upper half of the Fibonacci-Billet split lens can realize three phase-locking copies of the planar reference wave and the lower half is used to generate three identical copies of object. The interference pattern is recorded by a detector in one single exposure. The test object can be reconstructed by three-step phase-shifting interferometry. The corresponding experiment is carried out to verify the effectiveness of this method. With advantages of real-time reconstruction and amplitude-only diffraction lens, it is very useful for fast imaging and optical element detection.

20.
Sensors (Basel) ; 19(3)2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30704120

RESUMO

Soil moisture is an important aspect of heat transfer process and energy exchange between land-atmosphere systems, and it is a key link to the surface and groundwater circulation and land carbon cycles. In this study, according to the characteristics of the study area, an advanced integral equation model was used for numerical simulation analysis to establish a database of surface microwave scattering characteristics under sparse vegetation cover. Thus, a soil moisture retrieval model suitable for arid area was constructed. The results were as follows: (1) The response of the backscattering coefficient to soil moisture and associated surface roughness is significantly and logarithmically correlated under different incidence angles and polarization modes, and, a database of microwave scattering characteristics of arid soil surface under sparse vegetation cover was established. (2) According to the Sentinel-1 radar system parameters, a model for retrieving spatial distribution information of soil moisture was constructed; the soil moisture content information was extracted, and the results were consistent with the spatial distribution characteristics of soil moisture in the same period in the research area. (3) For the 0⁻10 cm surface soil moisture, the correlation coefficient between the simulated value and the measured value reached 0.8488, which means that the developed retrieval model has applicability to derive surface soil moisture in the oasis region of arid regions. This study can provide method for real-time and large-scale detection of soil moisture content in arid areas.


Assuntos
Ecossistema , Monitoramento Ambiental , Solo/química , Água/química , Conservação dos Recursos Naturais , Clima Desértico , Micro-Ondas , Radar , Propriedades de Superfície
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