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1.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 37(4): 441-444, 2020 Apr 10.
Artigo em Zh | MEDLINE | ID: mdl-32219832

RESUMO

OBJECTIVE: To detect pathological variant in two patients with Chediak-Higashi syndrome (CHS) from a consanguineous family and to explore its genotype-phenotype correlation. METHODS: Clinical data was collected for this pedigree. Genomic DNA was prepared from probands' peripheral leukocytes and their relatives' fingernail. Whole exome sequencing and Sanger sequencing were carried out to detect potential variant of the LYST gene. RESULTS: The proband presented with partial oculocutaneous albinism, immunodeficiency and acidophilic inclusion body in bone marrow and blood smears. A novel homozygous nonsense variant c.8782C>T (p.Gln2928*) was identified in exon 34 of the LYST gene in the sib pair. The same variant was found to be in heterozygous status in 6 unaffected individuals from the pedigree. CONCLUSION: Above result enriched the mutational spectrum of CHS and provided a basis for genetic counseling and prenatal diagnosis for this pedigree.


Assuntos
Síndrome de Chediak-Higashi/genética , Linhagem , Proteínas de Transporte Vesicular/genética , Éxons , Heterozigoto , Humanos , Mutação , Análise de Sequência de DNA , Sequenciamento do Exoma
2.
J Pediatr Hematol Oncol ; 41(3): 170-174, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30664102

RESUMO

In this study we evaluated children with newly diagnosed advanced (stage III and stage IV) mature B-cell non-Hodgkin lymphoma (B-NHL) or mature B-cell acute leukemia (B-AL), who were treated with Berlin-Frankfurt-Münster (BFM)95-based protocol combined with rituximab (R+BFM95). Our study recruited 46 patients who were treated with BFM95 protocol combined with rituximab. There are 23 patients as the historical control treated with BFM90 protocol. Compared with patients treated with BFM90 protocol, the 5-year event-free survival (EFS) rate of patients under R+BFM95 was higher (83.7%±5.7% vs. 69.6%±9.6%; P=0.1062). Among subgroups of our patients, the 5-year EFS of patients with stage III was 87.3%±6.1% vs. 77.8%±9.8% (P=0.2998), stage IV/B-AL was 72.7%±13.4% versus 40.0%±21.9% (P=0.0878) between patients treated with R+BFM95 and BFM90, respectively. Among patients whose lactate dehydrogenase (LDH) level were <500 U/L at diagnosis, R+BFM95 protocol reached 100% survival, nevertheless the 5-year EFS of patients in this group was not statistically different from that of patients treated with BFM90 (92.3%±7.4%; P=0.2994). Among patients had LDH≥500 U/L at diagnosis, the 5-year EFS in R+BFM95 group was 77.2%±7.7% (32 patients) and significantly higher than that of BFM90 group (40.0%±15.5%, 10 patients; P=0.0048). We found that rituximab has improved the EFS of childhood B-NHL/B-AL with LDH≥500U/L. Our results require validation from future studies with large cohort.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Rituximab/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Asparaginase/administração & dosagem , Estudos de Casos e Controles , Criança , China , Daunorrubicina/administração & dosagem , Feminino , Humanos , L-Lactato Desidrogenase/análise , Linfoma de Células B/tratamento farmacológico , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Prednisona/administração & dosagem , Intervalo Livre de Progressão , Estudos Retrospectivos , Rituximab/uso terapêutico , Resultado do Tratamento , Carga Tumoral , Vincristina/administração & dosagem
3.
Appl Opt ; 57(36): 10480-10484, 2018 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-30645392

RESUMO

Photonic Doppler velocimetry (PDV) has become a major domain velocity measurement technique for shock physics experiments. In this study, we propose and validate a bi-fiber quasi-axis probe for PDV that consists of a multimode source fiber and a single-mode detection fiber. This structure makes the received light by the probe totally reflected or scattered from the target, and, therefore, is free from the influence of unwanted return light. The light-receiving efficiency of the probe was calculated by the Monte Carlo method and was validated by static experiment. We validate that the feasibility of probe by dynamic experiments with measurement depth up to 6 cm. Above all, the bi-fiber quasi-axis probe is a promising supplementary probe for PDV for shock physics experiments.

4.
Pediatr Blood Cancer ; 61(4): 659-63, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24243691

RESUMO

BACKGROUND: This retrospective cohort study analysed the clinical characteristics and outcomes of patients with childhood lymphoblastic lymphoma (LBL) treated in Shanghai, China. PROCEDURE: From 2001 to 2010, 108 evaluable patients ≤16 years of age who were newly diagnosed with biopsy-proven LBL were treated with one of three treatment protocols: CCCG-99, SCMC-T-NHL-2002, or LBL-CHOF-2006. RESULTS: Two patients had Stage I disease, 5 had Stage II, 55 had Stage III, and 46 had Stage IV. The immunophenotype was T-cell LBL in 92 patients (85.2%) and precursor B-cell LBL in 16 (14.8%). The abandonment rate was 11.5%. Twenty-five patients (23.2%) suffered from resistant disease, including 1 with isolated central nervous system (CNS) relapse. At a median follow-up of 40.4 months (range, 0-114 months), the 5-year probability of event-free survival (pEFS) was 63.9 ± 4.6% in all patients. The 5-year pEFS for patients with pB-LBL was better than for patients with T-LBL (100% vs. 61.3 ± 5.1%, P = 0.007). Patients who had achieved complete remission on day 33 of induction had significantly better pEFS than those who had not (78.8 ± 4.6% vs. 28.2 ± 9.0%, P = 0.000). Three of 25 patients who experienced resistant disease were alive at the end of the study period. CONCLUSIONS: The abandonment rate was lower for patients with LBL than for patients with acute lymphoblastic leukemia. Prophylactic cranial radiation can be omitted for patients with LBL even when advanced-stage disease is present, as intensive systemic chemotherapy with intrathecal therapy is sufficient to prevent CNS relapse. The survival of patients with resistant disease was very poor.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Recidiva Local de Neoplasia/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras B/mortalidade , Leucemia-Linfoma Linfoblástico de Células T Precursoras/mortalidade , Adolescente , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Adulto Jovem
5.
Rev Sci Instrum ; 95(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38900096

RESUMO

A novel multi-longitudinal mode 532 nm photonic Doppler velocimetry (PDV) was proposed to solve the problem of high bandwidth requirements in shock experiments with velocities up to km/s. Compared to the conventional PDV system operating at 1550 nm, the utilization of a shorter wavelength of 532 nm enables nearly three times the velocity resolution. However, it also leads to a threefold increase in the Doppler frequency shift for a given velocity. To mitigate the bandwidth constraints, a multi-longitudinal mode laser is employed to downconvert the signal, effectively reducing the bandwidth requirements. The efficacy of this method is validated through theoretical analysis and experimental investigations on detonation shock scenarios. Furthermore, this approach eliminates the necessity for modulators, frequency shifters, and other devices, facilitating its applicability to non-communication bands.

6.
Microsc Res Tech ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963689

RESUMO

The quantification of 3D particle field is of interest for a vast range of fields. While in-line particle holography (PH) can provide high-resolution measurements of particles, it suffers from speckle noise. Plenoptic imaging (PI) is less susceptible to speckle noises, but it involves a trade-off between spatial and angular resolution, rendering images with low resolution. Here, we report a simple microscopy setup with the goals of getting the strengths of both techniques. It is built with off-the-shelf and cost-effective components including a photographic lens, a diaphragm, and a CCD camera. The cost of the microscopy setup is affordable to small labs and individual researchers. The pupil plane of the proposed setup can be mechanically accessible, allowing us to implement pupil plane modulation and increase the depth of field (DOF) without requiring any additional relay lenses. It also allows us to understand the working principle of pupil plane modulation clearly, benefiting microscopy education. It illuminates the sample (particles) using diffuse white light, and thus avoids the problem of speckle noise. It captures multiple perspective images via pupil plane modulation, without requiring trading off angular and spatial resolution. We validate the setup with 2D and 3D particle samples. RESEARCH HIGHLIGHTS: We report a simple and cost-effective microscopy setup with the goals of getting the strengths of plenoptic imaging and in-line particle holography. It is built with off-the-shelf and cost-effective components. The cost of the microscopy setup is affordable to small labs and individual researchers. The pupil plane of the proposed setup can be mechanically accessible, allowing us to implement pupil plane modulation and increase the DOF without requiring any additional relay lenses. It also allows us to understand the working principle of pupil plane modulation clearly, benefiting microscopy education. It illuminates the sample (particles) using diffuse white light, and thus avoids the problem of speckle noise. It captures multiple perspective images via pupil plane modulation, without requiring trading off angular and spatial resolution. We validate the setup with 2D and 3D particle samples.

7.
Int J Infect Dis ; 128: 205-211, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36632892

RESUMO

OBJECTIVES: To reveal the clinical and molecular characteristics of Bordetella pertussis (BP) prevalent in Shanghai, China. METHODS: A total of 9430 children with suspected pertussis from 2021 to 2022 were included, and nasopharyngeal swab samples were collected for polymerase chain reaction detection, culture, antimicrobial susceptibility testing, and 23S rRNA gene A2047G detection. BP strains were typed using multilocus variable-number tandem-repeat analysis and virulence genotyping. RESULTS: Of 9430 cases, 5.1% and 1.6% were confirmed by polymerase chain reaction and culture, respectively. Infants (aged <1 year) accounted for 24.7% and presented much more severe symptoms than noninfants. Pertussis was most frequently detected in infants aged 0-6 months (11.3∼14.0%) and children aged >6-10 years (10.8∼21.7%). Macrolide-resistant BP (MRBP) accounted for 89.3%, and all carried the A2047G mutation. There were six multilocus variable-number tandem-repeat analysis types (MTs), including MT28 (62.0%), MT195 (20%), MT27 (10.0%), MT104 (4.7%), MT55 (2.7%), and MT32 (0.7%). BP strains with pertussis toxin (ptx)P3/(pertactin) prn2/ptxC2/ptxA1/(fimbrial proteins) fim2-1/fim3-1, including MT27, MT28, and MT32, accounted for 72.7%, among which MT27 and MT32 were macrolide-sensitive BP, whereas most (94.6∼100%) of MT28 were MRBP. Strains harboring ptxP1/prn1/ptxC1/ptxA1/fim2-1/fim3-1, including MT55, MT104, and MT195, belonged to macrolide-sensitive BP. CONCLUSION: The emergence and spread of MT28 ptxP3-MRBP was first reported in China, highlighting the importance of continuous surveillance of ptxP3-MRBP to prevent its potential circulation.


Assuntos
Bordetella pertussis , Farmacorresistência Bacteriana , Coqueluche , Criança , Humanos , Lactente , Alelos , Antibacterianos , Bordetella pertussis/genética , China/epidemiologia , Genótipo , Macrolídeos , Coqueluche/epidemiologia
8.
Clin Med (Lond) ; 12(6): 568-71, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23342412

RESUMO

Using a community-based population cross-sectional study, we investigated the validity of an enzymatic method for glycated albumin (GA) measurements and evaluated its utility as a diagnostic tool for diabetes mellitus (DM). In total, 1,211 participants from the city of Harbin, People's Republic of China, were enrolled in the study. A receiver operating characteristic (ROC) analysis for GA, fasting plasma glucose (FPG) and haemoglobin A1c (HbA1c) measurements in diagnosed and undiagnosed DM were compared, based on a definition of DM using 1999 WHO criteria. We also estimated the correlation among GA, HbA1c and other clinical characteristics. Significant and positive correlations of fasting serum GA with FPG (r = 0.8097) and HbA1c (r = 0.8976) were found in participants enrolled in the study. ROC analysis for GA predicting undiagnosed DM with a cut-off point of 15.7% was similar to that of FPG and HbA1c. Therefore, our data indicate that GA is a potential tool for DM diagnosis.


Assuntos
Diabetes Mellitus/diagnóstico , Diabetes Mellitus/metabolismo , Hemoglobinas Glicadas/metabolismo , Albumina Sérica/metabolismo , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , China , Estudos Transversais , Feminino , Produtos Finais de Glicação Avançada , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Adulto Jovem , Albumina Sérica Glicada
9.
Zhonghua Zhong Liu Za Zhi ; 34(3): 222-7, 2012 Mar.
Artigo em Zh | MEDLINE | ID: mdl-22780979

RESUMO

OBJECTIVE: The aim of this study was to evaluate the efficacy and toxicity of the CCCG-97 and BFM-90 protocols in the treatment of pediatric patients with B-cell non-Hodgkin's lymphoma (B-NHL) retrospectively, and to explore the optimal therapeutic strategy. METHODS: Forty-five consecutive untreated patients (age of 18 years or less) with newly diagnosed B-NHL (including Burkitt Lymphoma and diffuse large B-cell lymphoma), treated in our hospital between July 1999 and December 2008 were enrolled in this study. The patients were classified into 2 groups by different protocols. From July 1999 to December 2004, twenty-one 3- to 13.8-year-old children were enrolled in the CCCG-97 group, with 1 in stage I/II, and 20 in stage III/IV(St Jude staging). From January 2005 to December 2008, twenty-four 2.8- to 14.1-year-old cases were enrolled in the BFM-90 group, with 3 in stage I/II, and 21 in stage III/IV (St Jude staging). The survival rates were evaluated by Kaplan-Meier analysis. RESULTS: Forty of the 45 patients (88.9%) reached complete response (CR) after 2 courses of chemotherapy. In the CCCG-97 group, the CR rate was 95.2% (20/21 pts), while that in the BFM-90 group was 83.3% (20/24 pts). At a median follow-up time of 62 (17 to 131) months, the 5-year event-free survival (EFS) was 71.8% for all patients, and 69.1% for Stage III/IV, respectively. In the CCCG-97 group, the 3-year EFS was 76.2%. In the BFM-90 group, it was 75.0%. There was no significant difference in survival rates between the CCCG-97 and BFM-90 groups (P=0.975). Unfavorable events recorded were as follows: Death of progression before achieving CR during induction therapy in 4 cases, and relapse after achieving CR in 6 cases. The relapse rates were 19.0% (4/21 pts) in the CCCG-97 group and 8.3% (2/24 pts) in the BFM-90 group, with a non-significant statistical difference (P=0.292). Major toxicities were myelosuppression and mucositis, especially in the BFM-90 group, but were tolerable and manageable. five patients in the BFM-90 group received rituximab, 2 patients (Stage III) achieved CR, while the other 3 patients (Stage IV) had progressive disease or relapse. CONCLUSIONS: Short-pulse and intensive chemotherapy, stratified according to stage of disease, can improve the survival rate of pediatric mature B-NHL. The efficacy of the CCCG-97 protocol and BFM-90 protocol is comparable and the toxicity is tolerable.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma de Burkitt/tratamento farmacológico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Adolescente , Anticorpos Monoclonais Murinos/uso terapêutico , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Linfoma de Burkitt/patologia , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Linfoma Difuso de Grandes Células B/patologia , Masculino , Mucosite/induzido quimicamente , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Indução de Remissão , Estudos Retrospectivos , Rituximab , Taxa de Sobrevida
10.
Front Pharmacol ; 13: 933739, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35979231

RESUMO

Cyclosporine (CsA) is a component of the first-line treatment for acquired aplastic anemia (acquired AA) in pediatric patients. This study aimed to develop a population pharmacokinetic (PK) model of CsA in Chinese pediatric patients with acquired AA to inform individual dosage regimens. A total of 681 CsA whole blood concentrations and laboratory data of 157 pediatric patients with acquired AA were retrospectively collected from two hospitals in Shanghai. A nonlinear mixed-effect model approach was used to build the population PK model. Potential covariate effects of age, body weight, and biochemical measurements (renal and liver functions) on CsA PK disposition were evaluated. Model fit was assessed using the basic goodness of fit and a visual predictive check. The CsA concentration data were accurately described using a two-compartment disposition model with first-order absorption and elimination. Body weight value was implemented as a fixed allometric function on all clearance and volume of distribution parameters. Total bilirubin level was identified as a significant covariate on apparent clearance (CL/F), with a 1.07% reduction per 1 nmol/L rise in total bilirubin level. The final estimates for CL/F and central volume (Vc/F) were 29.1 L/h and 325 L, respectively, for a typical 28 kg child. Other covariates (e.g., gender, age, albumin, hemoglobin, hematocrit, serum creatinine, and concomitant medication) did not significantly affect the PK properties of CsA. This population PK model, along with a maximum a posteriori Bayesian approach, could estimate individual PK parameters in pediatric patients with acquired AA to conduct individual CsA therapy.

11.
Front Pharmacol ; 12: 701452, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34326772

RESUMO

High-dose methotrexate (HD-MTX) is widely used in pediatric acute lymphoblastic leukemia (ALL) treatment regimens. In this study, we aimed to develop a population pharmacokinetic (PK) model of HD-MTX in Chinese pediatric patients with ALL for designing personalized dosage regimens. In total, 4,517 MTX serum concentration data for 311 pediatric patients with ALL, aged 0.75-15.2 years and under HD-MTX treatment, were retrospectively collected at a tertiary Children's Hospital in China. The non-linear mixed-effect model was used to establish the population PK model, using NONMEM software. The potential covariate effects of age, body weight, and biochemical measurements (renal and liver function) on MTX PK disposition were investigated. The model was then evaluated using goodness-of-fit, visual predictive check. MTX PK disposition was described using a three-compartment model reasonable well. Body weight, implemented as a fixed allometric function on all clearance and volume of distribution parameters, showed a substantial improvement in model fit. The final population model demonstrated that the MTX clearance estimate in a typical child with body weight of 19 kg was 6.9 L/h and the central distribution of volume estimate was 20.7 L. The serum creatinine significantly affected the MTX clearance, with a 0.97% decrease in clearance per 1 µmol/L of serum creatinine. Other covariates (e.g., age, sex, bilirubin, albumin, aspartate transaminase, concomitant medication) did not significantly affect PK properties of MTX. The proposed population PK model could describe the MTX concentration data in Chinese pediatric patients with ALL. This population PK model combined with a maximum a posteriori Bayesian approach could be used to estimate individual PK parameters, and optimize personalized MTX therapy in target patients, thus aiming to reduce toxicity and improve treatment outcomes.

12.
Transl Pediatr ; 9(1): 4-12, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32154130

RESUMO

BACKGROUND: Acute lymphoblastic leukemia (ALL) is the most common malignancy in children, while relapse and refractory ALL remains a leading cause of death in children. However, paired ALL samples of initial diagnosis and relapse subjected to next-generation sequencing (NGS) could construct clonal lineage changes, and help to explore the key issues in the evolutionary process of tumor clones. Therefore, we aim to analyze gene alterations during the initial diagnosis and relapse of ALL patients and to explore the underlying mechanism. METHODS: Targeted exome sequencing technology was used to detect molecular characteristic of initial diagnosis and relapse of ALL in 12 pediatric patients. Clinical features, treatment response, prognostic factors and genetic features were analyzed. RESULTS: In our 12 paired samples, 75% of pre-B-cell acute lymphoblastic leukemia (B-ALL) patients had alterations in the Ras pathway (NRAS, KRAS, NF1, and EPOR), and Ras mutation are very common in patients with ALL relapse. TP53 mutations mainly existed in the primary clones and occurred at the initial diagnosis and relapse of ALL. Relapse-associated genes such as NT5C2 and CREBBP were observed in patients with ALL relapse; however, all patients included in this study had gene abnormalities in the Ras pathway, and NT5C2 and CREBBP genes may collaboratively promote ALL relapse. CONCLUSIONS: Among the 12 ALL patients, Ras pathway mutations are common in ALL relapse and may be associated with other recurrence-related genes alterations. The study with paired samples could improve the understanding of ALL relapse.

13.
Ann Transl Med ; 7(14): 296, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31475166

RESUMO

BACKGROUND: Acute lymphoblastic leukemia (ALL), the most common childhood malignancy, is characterized by molecular aberrations. Recently, genetic profiling has been fully investigated on ALL; however, the interaction between its genetic alterations and clinical features is still unclear. Therefore, we investigated the effects of genetic variants on ALL phenotypes and clinical outcomes. METHODS: Targeted exome sequencing technology was used to detect molecular profiling of 140 Chinese pediatric patients with ALL. Correlation of genetic features and clinical outcomes was analyzed. RESULTS: T-cell ALL (T-ALL) patients had higher initial white blood cell (WBC) count (34.8×109/L), higher incidence of mediastinal mass (26.9%), more relapse (23.1%), and enriched NOTCH1 (23.1%), FBXW7 (23.1%) and PHF6 (11.5%) mutations. Among the 18 recurrently mutated genes, SETD2 and TP53 mutations occurred more in female patients (P=0.041), NOTCH1 and SETD2 mutants were with higher initial WBC counts (≥50×109/L) (P=0.047 and P=0.041), JAK1 mutants were with higher minimal residual disease (MRD) level both on day 19 and day 46 (day 19 MRD ≥1%, P=0.039; day 46 MRD ≥0.01%, P=0.031) after induction chemotherapy. Multivariate analysis revealed that initial WBC counts (≥50×109/L), MLLr, and TP53 mutations were independent risk factors for 3-year relapse free survival (RFS) in ALL. Furthermore, TP53 mutations, age (<1 year or ≥10 years), and MLLr were independently associated with adverse outcome in B-cell ALL (B-ALL). CONCLUSIONS: MLLr and TP53 mutations are powerful predictors for adverse outcome in pediatric B-ALL and ALL. Genetic profiling can contribute to the improvement of prognostication and management in ALL patients.

14.
Rev Sci Instrum ; 84(1): 013101, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23387631

RESUMO

A fiber interferometry for transverse velocity measurement has been developed. This diagnostic is similar to photonic Doppler velocimetry in the way in which laser propagates and couples. The interferometer mainly consists of a fiber coupler, an emitting probe, and two receiving probes. A pair of scattered laser beams mix in the coupler and generates fringes with frequency proportional to transverse velocity. Measurement of transverse velocity is independent of longitudinal velocity. The feasibility of the technique has been verified by rotating wheel experiment and shock loading experiment.

15.
Rev Sci Instrum ; 82(10): 103109, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22047282

RESUMO

A fiber Bragg grating (FBG) sensor with an unbalanced Mach-Zehnder fiber interferometer for the shock stress measurement is proposed and demonstrated. An analysis relationship between the shock stress and the central reflection wavelength shift of the FBG is firstly derived. In this sensor, the optical path difference of the unbalanced Mach-Zehnder fiber interferometer is ~3.1 mm and the length of the FBG is 2 mm. An arctangent function reduction method, which can avoid sine function's insensitive zone where the shock stress measurement has a reduced accuracy, is presented. A shock stress measurement of water driven by one stage gun (up to 1.4 GPa), with good theoretical accuracy (~10%), is launched.

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