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1.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 48(3): 296-302, 2019 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-31496162

RESUMO

OBJECTIVE: To investigate the effects of high dose vitamin C (VC) on proliferation of breast cancer cells and to explore its mechanisms. METHODS: Human breast cancer cells Bcap37 and MDA-MB-453 were treated with VC at low dose (0.01 mmol/L), medium dose (0.10 mmol/L) and high dose (2.00 mmol/L). Cell proliferation was determined with CCK-8 assay, protein expression was evaluated by Western blot, and the secretion of lactic acid in tumor cells was detected by colorimetric method. Bcap37 cells were inoculated in nude mice, and tumor baring nude mice were intraperitoneally injected with high VC(4 g/kg, VC group, n=5)or normal saline (control group, n=5) for 24 d. Tumor weight and body weight were calculated. RESULTS: In vitro experiments demonstrated that high dose VC significantly inhibited cell proliferation in Bcap37 and MDA-MB-453 cells (all P<0.01); the expressions of Glut1 and mTOR signaling pathway-related proteins were decreased (all P<0.05); and the secretion of lactic acid was also markedly reduced (all P<0.05). In vivo experiment showed that the tumor weight was decreased in mice treated with high-dose VC as compared with control group (P<0.05), but no difference in body weights between two groups was observed. CONCLUSIONS: High dose VC may inhibit proliferation of breast cancer cells both in vitro and in vivo through reducing glycolysis and protein synthesis.


Assuntos
Ácido Ascórbico , Neoplasias da Mama , Glicólise , Biossíntese de Proteínas , Animais , Ácido Ascórbico/farmacologia , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Humanos , Camundongos , Camundongos Nus , Biossíntese de Proteínas/efeitos dos fármacos
2.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(9): 922-925, 2019 Sep 10.
Artigo em Chinês | MEDLINE | ID: mdl-31515791

RESUMO

OBJECTIVE: To report a patient with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) manifesting as lumbago, hunchback and Parkinson's syndrome. METHODS: A 49-years-old male CADASIL patient was reported. Results of clinical examination, neuroimaging and genetic testing were analyzed. His family members were also subjected to genetic testing. Related literature was reviewed. RESULTS: The patient had no typical symptoms of CADASIL such as headache, repeated stroke, dementia and emotional disorders, but progressive Parkinson's syndrome, late onset lumbago, hunchback, dysphagia, and diplopia. Brain MRI showed left basal ganglia and external capsule lacunar infarction. Genetic testing revealed a point mutation c.1630C>T (p.R544C) in exon 11 of the NOTCH3 gene. A heterozygous mutation was detected in the same gene in his mother, elder sister and younger brother, all of whom showed different clinical phenotypes. CONCLUSION: The clinical features of CADASIL are heterogeneous. Lumbago, humpback, and Parkinson's syndrome may be a rare clinical phenotype of CADASIL.

3.
Appl Opt ; 58(20): 5563-5567, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31504028

RESUMO

A polarization simulation and analysis method was carried out for a hyper numerical apertures (NA) lithography illumination system which is affected by residual birefringence in optical materials. The lens is divided into multiple small annuli according to the finite element method, and the retardation distribution is obtained by setting the residual birefringence of each annulus. Finally, the polarized ray tracing is cleverly changed to geometric ray tracing. A hyper-NA lithography illumination system is modeled, and the residual birefringence is set between 0.1 nm/cm and 1 nm/cm. The simulation result shows that the degree of polarization performance degradation is proportional to the magnitude of residual birefringence, and the tolerance of residual birefringence in lens materials is below 1 nm/cm for the system. The polarization simulation and analysis method provides a powerful tool to calculate the polarized parameters of the system, which is helpful for selecting lens material of the hyper-NA illumination system.

4.
Exp Cell Res ; : 111595, 2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31505165

RESUMO

LncRNA plays a vital role in many diseases, and abnormal expression of LncRNA has been reported in many types of tumors. In this study, we analyzed the available public TCGA and GEO databases, and found that the expression of SNHG3 was increased in clear cell renal cell carcinoma (ccRCC), which was positively correlated with many clinicopathological parameters, and the higher expression of SNHG3 predicted worse clinical prognosis. Functional experiments indicated that knockdown of SNHG3 could significantly inhibit the proliferation and metastasis of ccRCC in vitro and in vivo. Subsequently, through luciferase reporter assays, qPCR and rescue experiments, it was found that SNHG3 could bind to miR-139-5p, thereby up-regulating the expression of its target gene TOP2A, and play a role in promoting tumor progression in ccRCC. The correlation analysis showed that there was a significant positive correlation between the expression of SNHG3 and TOP2A, and both of them were significantly negative correlated with the expression of miR-139-5p. Our work suggested that the SNHG3/mir-139-5p/TOP2A axis plays an important role in the proliferation and metastasis of ccRCC, and was expected to be a new biomarker for diagnosis, prognosis and a target for treatment of ccRCC.

5.
J Cell Mol Med ; 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31454149

RESUMO

DYRK1A is considered a potential cancer therapeutic target, but the role of DYRK1A in NSCLC oncogenesis and treatment requires further investigation. In our study, high DYRK1A expression was observed in tumour samples from patients with lung cancer compared with normal lung tissues, and the high levels of DYRK1A were related to a reduced survival time in patients with lung cancer. Meanwhile, the DYRK1A inhibitor harmine could suppress the proliferation of NSCLC cells compared to that of the control. As DYRK1A suppression might be effective in treating NSCLC, we next explored the possible specific molecular mechanisms that were involved. We showed that DYRK1A suppression by siRNA could suppress the levels of EGFR and Met in NSCLC cells. Furthermore, DYRK1A siRNA could inhibit the expression and nuclear translocation of STAT3. Meanwhile, harmine could also regulate the STAT3/EGFR/Met signalling pathway in human NSCLC cells. AZD9291 is effective to treat NSCLC patients with EGFR-sensitivity mutation and T790 M resistance mutation, but the clinical efficacy in patients with wild-type EGFR remains modest. We showed that DYRK1A repression could enhance the anti-cancer effect of AZD9291 by inducing apoptosis and suppressing cell proliferation in EGFR wild-type NSCLC cells. In addition, harmine could enhance the anti-NSCLC activity of AZD9291 by modulating STAT3 pathway. Finally, harmine could enhance the anti-cancer activity of AZD9291 in primary NSCLC cells. Collectively, targeting DYRK1A might be an attractive target for AZD9291 sensitization in EGFR wild-type NSCLC patients.

6.
Ying Yong Sheng Tai Xue Bao ; 30(8): 2829-2836, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418209

RESUMO

Based on the bottom trawl surveys in spring (May) and in autumn (September to October) from 2011 to 2017 (except 2012) in Haizhou Bay, variations in the mean trophic levels (MTL) and large fish index (LFI) of fish community were examined to understand the changes of fish community structure in Haizhou Bay. The results showed that the dominant fish species were Hexagrammos otakii, Enedrias fangi, Syngnathus acus, Pseudosciaena polyactis and Saurida elongata, which had obvious seasonal variation. The mean trophic level of fish community varied significantly among different years and seasons. Generally, MTL in autumn was higher than that in spring, and the variation of which in autumn always lagged behind that in spring. The result of LFI calculation showed that the large fish resources declined and fish community structure in Haizhou Bay showed an obvious tendency of miniaturization in recent years.


Assuntos
Baías , Peixes/fisiologia , Animais , China , Peixes/classificação , Perciformes , Estações do Ano
7.
Methods Mol Biol ; 2040: 423-448, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31432491

RESUMO

Tracking cells is one of the main challenges in biology, as it often requires time-consuming annotations and the images can have a low signal-to-noise ratio while containing a large number of cells. Here we present two methods for detecting and tracking cells using the open-source Fiji and ilastik frameworks. A straightforward approach is described using Fiji, consisting of a pre-processing and segmentation phase followed by a tracking phase, based on the overlapping of objects along the image sequence. Using ilastik, a classifier is trained through manual annotations to both detect cells over the background and be able to recognize false detections and merging cells. We describe these two methods in a step-by-step fashion, using as example a time-lapse microscopy movie of HeLa cells.

8.
Methods Mol Biol ; 2040: 449-463, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31432492

RESUMO

Segmentation is one of the most ubiquitous problems in biological image analysis. Here we present a machine learning-based solution to it as implemented in the open source ilastik toolkit. We give a broad description of the underlying theory and demonstrate two workflows: Pixel Classification and Autocontext. We illustrate their use on a challenging problem in electron microscopy image segmentation. After following this walk-through, we expect the readers to be able to apply the necessary steps to their own data and segment their images by either workflow.

9.
Sheng Wu Gong Cheng Xue Bao ; 35(7): 1151-1161, 2019 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-31328472

RESUMO

Microbial cells cultivation is not only the origin, but also the foundation of microbiology. Researches in microbiology can only be carried out when the microbial cells can be cultured. However, conventional microbial cell cultivation is not only time consuming and labour intensive, but human error is also inevitable. Recent years, automated, modularised microbial cells micro-cultivation systems with small volume, good controllability, and equipped with real-time monitoring system have attracted great attention in microbiology. This review presents the state-of-the-art micro-cultivation systems which are implemented in microbial cells cultivation. The key development, applications of various system classified based on their construction, and the prospects of micro-cultivation system are discussed and insights into them are also provided.


Assuntos
Reatores Biológicos , Humanos
10.
Bioresour Technol ; 290: 121773, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31310867

RESUMO

The goal of this research was to release fermentable reducing sugar from lignocellulose (poplar) by hot water pretreatment, and then employed to synthesize poly(3-hydroxybutyrate-co-3-hydroxy-valerate) (PHBV) using activated sludge to replace traditional petroleum-based polymers. The orthogonal experiment was used to optimize the conditions of different pretreatment temperature, pretreatment time, enzymatic hydrolysis temperature and enzymatic hydrolysis time and the optimal condition for producing sugars was pretreated at 200 °C for 30 min and enzymatic hydrolysis at 45 °C for 3d. A maximum yield was 530.3 mg/g of reduced sugar, while the furfural and 5-HMF produced in the optimum conditions were 512.61 mg/L and 239.34 mg/L. Moreover, the effects of increasing concentration of hot water pretreated poplar hydrolysates (500-1700 mg/L) on PHBV production were investigated. Poplar hydrolysate (1700 mg/L) exhibited maximum PHBV concentration of 637.556 mg/L.

11.
Anal Chem ; 91(15): 9361-9365, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31269792

RESUMO

Efficient platforms for intracellular delivery of nucleic acids are essential for biomedical imaging and gene regulation. We develop a recombinant fusion streptavidin as a novel protein scaffold for DNA nanotetrads for highly efficient nucleic acid delivery and telomerase activity imaging in living cells via cross-linking hybridization chain reaction (cHCR). The recombinant streptavidin protein is designed to fuse with multiple SV40 NLS (nuclear localization signal) and NES (nuclear export signal) domains and prepared through Escherichia coli expression. The recombinant NLS-SA protein allows facile assembly with four biotinylated DNA probes via high-affinity noncovalent interactions, forming a well-defined DNA tetrad nanostructure. The DNA nanotetrads are demonstrated to confer efficient cytosolic delivery of nucleic acid via a caveolar mediated endocytosis pathway, allowing efficient escape from lysosomal degradation. Moreover, the nanotetrads enable efficient cHCR assembly in response to telomerase in vitro and in cellulo, affording ultrasensitive detection and spatially resolved imaging for telomerase with a detection limit as low as 90 HeLa cells/mL. The fluorescence brightness obtained in live cell imaging is found to be dynamically correlated to telomerase activity and the inhibitor concentrations. Therefore, the proposed strategy may provide a highly efficient platform for nucleic acid delivery and imaging of biomarkers in living cells.

12.
Chem Commun (Camb) ; 55(64): 9535-9538, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31334508

RESUMO

Endoperoxide-containing antimalarials, such as artemisinin and the synthetic trioxolane OZ439, are prodrugs activated by heme to generate primary and secondary carbon-centered radicals. We employed activity-based protein profiling (ABPP) to show that the secondary-carbon-centered radical of 1,2,4-trioxolanes is primarily responsible for protein labeling in malaria parasites.


Assuntos
Carbono/metabolismo , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/metabolismo , Animais
13.
Mol Med Rep ; 20(3): 2396-2402, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31322227

RESUMO

Long­term peritoneal dialysis is often limited or interrupted due to the development and progression of peritoneal fibrosis. Accumulating evidence suggests that epithelial­mesenchymal transition (EMT) is a major component of peritoneal injury associated with peritoneal fibrosis in the end stage of renal disease; however, at present, the underlying mechanisms remain unclear. Thus, in the present study, uric acid (UA)­induced EMT of peritoneal mesothelial cells was investigated by western­blot and immunofluorescence staining. The results revealed that peritoneal mesothelial cells stimulated with UA underwent EMT, as demonstrated by the decreased expression of epithelial markers (E­cadherin) and an increased expression of mesenchymal markers (α­smooth muscle actin and vimentin). Additionally, it was reported that UA could facilitate the progression of EMT of peritoneal mesothelial cells via EMT transcription pathways, including transforming growth factor­ß1/mothers against decapentaplegic homolog 3 and P38/mitogen­activated protein kinase by western­blot and reverse transcription semi­quantitative polymerase chain reaction. The results of the present study suggest that UA could promote EMT and may contribute to peritoneal chronic disease. Furthermore, the data obtained suggest that the levels of blood UA may account for the development of EMT; thus, lowering the levels of blood UA may be beneficial to inhibit the occurrence and development of peritoneal fibrosis.

14.
J Food Prot ; 82(8): 1292-1299, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31310167

RESUMO

Deoxynivalenol (DON) is a potent mycotoxin produced by many Fusarium spp. that invade grains during the growth and storage seasons. Lactic acid bacteria have been reported to be capable of removing several toxins, thereby providing an effective detoxification method for possible contaminated substrates. The present study mainly focused on investigating the detoxification characteristics of DON by a Lactobacillus paracasei LHZ-1 strain, which was recently isolated from yogurt with a strong promise of removing DON from liquid culture. The results obtained showed that the cell wall of L. paracasei LHZ-1 can remove up to 40.7% of 50 µg/mL DON, whereas only 10.5 and 8.9% are removed by the culture supernatant or cellular lysate, respectively. Laser scanning confocal microscopy helped to identify the mechanism of DON detoxification by L. paracasei LHZ-1 through cellular adsorption, where DON was found to bind to the surface of bacterial cells to form complexes. In stability tests, about 39 or 99% of bound DON, either to viable bacterial cells or heat-inactivated cells, respectively, was released by methanol extractions, which indicated that the binding force between viable cells and DON could be stronger than it is in heat-inactivated cells. Adsorption kinetics demonstrated that approximately 33% of DON was removed within 20 h, with a maximum adsorption capacity of approximately 50.5 µg/mL in phosphate-buffered solution.

15.
J Food Prot ; 82(8): 1283-1291, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31310169

RESUMO

The use of natural preservatives has attracted considerable attention owing to their generally safe and environmentally friendly properties. In this study, we investigated the effects of the preservative A1, composed of plantaricin 163, thymol, and surfactin, on bacterial communities and storage quality of refrigerated crucian carp. A total of 522 operational taxonomic units belonging to 20 phyla and 272 genera were identified by high-throughput sequencing, showing a comprehensive coverage of bacterial composition of crucian carp. In untreated samples after spoilage, Brochothrix was the predominant genus, followed by Aeromonas and Pseudomonas. After treatment with A1, the growth of these spoilage bacteria was significantly inhibited according to high-throughput sequencing and plate counts, and Lactococcus became the most abundant organism at the end of storage. Meanwhile, compared with control samples, the shelf life of A1-treated samples extended from 3 to 12 days on the basis of the sensory evaluation and the total viable counts. Furthermore, the total volatile basic nitrogen, thiobarbituric acid, and pH values for A1-treated samples were significantly lower than that of control samples. The results indicate that preservative A1 has potential commercial application in the preservation of refrigerated crucian carp.

16.
J Orthop Trauma ; 33(8): e291-e295, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31335568

RESUMO

OBJECTIVES: To evaluate the utility of follow-up radiographs in patients with isolated partial articular radial head fractures (OTA/AO 2R1B1 or 2R1B3). DESIGN: Retrospective cohort study. SETTING: Academic Level 1 Trauma Center. PATIENTS: Adult patients (≥18 years) with isolated partial articular radial head fractures indicated for initial nonoperative treatment. INTERVENTION: Analysis of elbow radiographs at initial presentation and at postinjury follow-up of 3-8 weeks. VARIABLES MEASURED: Articular gap and step-off. MAIN OUTCOME MEASURE: Radiographic articular displacement between initial and follow-up radiographs. RESULTS: For 72 included patients, initial radiographs were obtained on average 2.6 days after injury and follow-up radiographs 33.7 days thereafter. Equivalence tests evaluating gap and step-off thresholds of <1 mm were both significant, indicating that the cohort displaced <1 mm for both parameters between initial and follow-up radiographs. No patients proceeded to surgical treatment following the repeat radiographs. CONCLUSIONS: These fractures do not displace in the early postinjury period, as defined as a <1 mm of change in both intra-articular gap and step-off, as compared to initial radiographs. Routine follow-up radiographs for these injuries is a source of cost, but with limited utility in detecting interval displacement or leading to a change in management. Selective use of radiographs to evaluate specific clinical concerns may lead to cost savings. LEVEL OF EVIDENCE: Diagnostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

17.
J Cell Biochem ; 120(11): 18650-18658, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31338877

RESUMO

This study aims to explore the ability of magnetic resonance imaging (MRI) in mucin 1 (MUC1) modified superparamagnetic iron oxide nanoparticle (SPION) targeting human pancreatic cancer (PC). The MUC1 target-directed probe was prepared through MUC1 conjugated to SPION using the chemical method to assess its physiochemical characteristics, including hydration diameter, surface charge, and magnetic resonance signal. The cytotoxicity of MUC1-USPION was verified by MTS assay. BxPC-3 was cultured with MUC1-USPION and SPION in different concentrations. The combined condition of the targeted probes and cells were observed through Prussian blue staining. The nude mice model of pancreatic cancer was established to investigate the application of the probe. MRI was performed to determine the intensity of the signal of the transplanted tumor, while immunohistochemistry and Western blot analysis were performed to detect the expression of MUC1 after taking the transplanted tumor specimen. The particle size of the prepared molecular probe was 63.5 ± 3.2 nm, and the surface charge was 10.2 mV. Furthermore, the probe solution could significantly reduce the MRI at T2 , and the magnetic resonance transverse relaxation rate (ΔR2 ) has a linear relationship with the concentration of iron in the solution. The cell viability of MUC1-USPION in different concentrations revealed no statistical difference, according to the MTS assay. In vitro, the MRI demonstrated decreased T2WI signal intensity in both groups, especially the targeting group. In vivo, MUC1 could selectively accumulate in the nude mice model, and significantly reduce the T2 signal strength. In subsequent experiments, the expression of MUC1 was high in pancreatic cancer tissues, but low in normal pancreatic tissues, as determined by immunohistochemistry and Western blot analysis. The prepared samples can be combined with pancreatic cancer tissue specificity by in vivo imaging, providing reliable early in vivo imaging data for disease diagnosis.

18.
J Bone Joint Surg Am ; 101(113): e63, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31274728

RESUMO

BACKGROUND: U.S. orthopaedic residency training is anchored by the Accreditation Council for Graduate Medical Education (ACGME) requirements, which include minimum numbers for 15 categories of procedures. The face validity of these recommendations and expectations for exposure to other common procedures has not been rigorously investigated. The main goals of this investigation were to understand the perceptions of program directors and early practice surgeons regarding the number of cases needed in residency training and to report which of the most commonly performed procedures residents should be able to perform independently upon graduation. METHODS: We sent surveys to 157 current program directors of ACMGE-approved orthopaedic surgery residency programs and to all examinees sitting for the American Board of Orthopaedic Surgery (ABOS) Part II Oral Examination in 2017, requesting that they estimate the minimum number of exposures for the 22 adult and 24 pediatric procedures that are most commonly performed during residency and the first 2 years in practice. Where applicable, we compared these with the ACGME "Minimum Numbers" and the average ACGME resident experience data from 2010 to 2012 for resident graduates. For each of the 46 procedures, participants were asked if every orthopaedic resident should be able to independently perform the procedure upon graduation. We compared the percent for independence between the early practice surgeons and the program directors. RESULTS: For the majority of adult and pediatric procedures, the early practitioners reported significantly higher numbers of cases needing to be performed during residency than the program directors. ACGME Minimum Numbers were always lower than the case numbers that were recommended by the early practice surgeons and the program directors. Overall we found good-to-excellent agreement for independence at graduation between program directors and early practitioners for adult cases (intraclass correlation coefficient [ICC], 0.98; 95% confidence interval [CI], 0.82 to 0.99) and moderate-to-good agreement for pediatric cases (ICC, 0.96; 95% CI, 0.74, 0.99). CONCLUSIONS: The program directors frequently perceived the need for resident operative case exposure to common orthopaedic procedures to be lower than that estimated by the early practice surgeons. Both program directors and early practice surgeons generally agreed on which common cases residents should be able to perform independently by graduation.

19.
J Biosci Bioeng ; 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31326332

RESUMO

Directed evolution methodologies have been used as promising strategies for improving the catalytic properties of many existing enzymes. In the presented work, this approach was applied to improve the enzyme activity of l-asparaginase I obtained from Bacillus megaterium H-1. After two rounds of error-prone polymerase chain reaction (epPCR) and two generations of sequential DNA shuffling, all of 5 different mutants showed a significant increase in the enzyme activity of l-asparaginase I, ranging from 6.27 to 22.78 IU/mL. Among these mutants, D-9B and DD-12G displayed the relatively high catalytic activity, which were 20.22-fold and 21.33-fold higher than the wild-type enzyme (WT), respectively. Furthermore, the catalytic efficiency (kcat/Km) of D-9B and DD-12G were also improved, which were 132.73 min-1mM-1 and 146.39 min-1mM-1, respectively, in comparison to that of WT (3.39 min-1mM-1). In addition, mutant DD-12G showed tolerance toward wider range of pH values and higher temperatures than its WT counterpart. Homology modeling of above two mutants reflected a reduction of hydrogen bonds and an introduction of flexible residues in the loops near the active catalytic site Thr15. These changes contributed to the flexibility of loops, which may lead to further enhancement in catalytic efficiency. Results also showed that approximately 88.5% (0.978 mg/kg) acrylamide could be removed from mutant DD-12G pre-treated fried potato chips. This study clearly shows that directional evolution methods can indeed be utilized to improve the activity of l-asparaginase, which could also provide research basis for future application in food industry.

20.
Sensors (Basel) ; 19(14)2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31319596

RESUMO

The Gravity Recovery and Climate Experiment (GRACE) level-2 spherical harmonic (SH) solutions are noisy and thus require filtering. Filtering reduces noise but affects signal quality via signal leakage. Generally, a leakage correction is required for GRACE applications to remove leakage signal and recover the true signal. Forward modelling based on some a priori information is a widely used approach for leakage correction of GRACE data. The a priori information generally relies on global hydrological model simulations. There are many global hydrological models and therefore it is of interest to explore how different global hydrology model simulations influence leakage correction results. This study investigated the sensitivity of three leakage correction methods (additive method, scaling factor method and multiplicative method) to five global hydrology model simulations (four models from the Global Land Data Assimilation System (GLDAS) and the WaterGAP Global Hydrology Model (WGHM)). The sensitivity analysis was performed with observational data in Southwest China and one sub-region, Guangxi. Results show that although large differences were identified among the five global model simulations, the additive and scaling factor methods are less affected by the choice of a priori model in comparison to the multiplicative approach. For the additive and scaling factor methods, WGHM outperforms the other four GLDAS models in leakage correction of GRACE data. GRACE data corrected with the multiplicative method shows the highest amount of error, indicating this method is not applicable for leakage correction in the study area. This study also assessed the level-3 mascon (mass concentration) solutions of GRACE data. The mascon-based results are nearly as good as the leakage corrected results based on SH solutions.

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