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Peng J, Jiang Y, Ai C, Liu Y, Lin X, Zhou J, Zhang J. Body burden and influencing factors of polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs) in male workers from a municipal waste incineration plant in China. Environ Pollut 2022; 305:119272. [PMID: 35413407 DOI: 10.1016/j.envpol.2022.119272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 03/30/2022] [Accepted: 04/04/2022] [Indexed: 06/14/2023]
Abstract
Emissions of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) from municipal solid waste incinerators (MSWIs) have aroused public concern around the world. However, biomonitoring evidence regarding the influence of MSWIs on the human body burden of PCDD/Fs is scarce. The aim of this study is to investigate the human body burden levels of PCDD/Fs in MSWI workers and to further explore the potential influencing factors, including duration of occupation and dietary habits, on the PCDD/F levels. A total of 98 paired serum samples from MSWI workers and non-MSWI workers were collected. Seventeen 2,3,7,8-chlorine substituted PCDD/Fs in the serums were analyzed using an isotope dilution high-resolution gas chromatograph/high-resolution mass spectrometer (HRGC/HRMS). The results showed that the mean levels of toxic equivalent (TEQ)-PCDD/Fs for the MSWI workers and the control group were 18.28 pg TEQ g-1 lipid and 5.81 pg TEQ g-1 lipid, respectively. Significantly higher concentrations of PCDD/Fs existed in the incinerator workers compared with the control subjects after adjustment of the confounding factors. OCDD was the most abundant congener in both the MSWI workers and the control subjects, accounting for 82.2% and 89.4% of the ∑17PCDD/Fs, respectively. The serum levels of PCDFs in the MSWI workers increased with the duration of occupation (β = 0.498, P = 0.031), and a higher total concentration of PCDD/Fs were present in senior workers classified as production supervisors than routine operation staff (β = 8.809, P = 0.008). No significant relationship was found between the PCDD/F concentrations and dietary habits. This study was the first to explore the associations between the body burden of PCDD/Fs and occupational exposure as well as dietary intake of MSWI workers in China. The findings provide scientific information for health risk assessments of human exposure to PCDD/Fs.
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Affiliation(s)
- Jinling Peng
- Shenzhen Center for Disease Control and Prevention, Shenzhen, 518055, PR China
| | - Yousheng Jiang
- Shenzhen Center for Disease Control and Prevention, Shenzhen, 518055, PR China
| | - Chunyan Ai
- Shenzhen Center for Disease Control and Prevention, Shenzhen, 518055, PR China; Shenzhen Maternity & Child Healthcare Hospital, Shenzhen, 518017, PR China
| | - Yuan Liu
- Shenzhen Center for Disease Control and Prevention, Shenzhen, 518055, PR China
| | - Xiaoshi Lin
- Shenzhen Center for Disease Control and Prevention, Shenzhen, 518055, PR China
| | - Jian Zhou
- Shenzhen Center for Disease Control and Prevention, Shenzhen, 518055, PR China
| | - Jianqing Zhang
- Shenzhen Center for Disease Control and Prevention, Shenzhen, 518055, PR China.
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Liang Y, Tang Z, Jiang Y, Ai C, Peng J, Liu Y, Chen J, Xin X, Lei B, Zhang J, Cai Z. Lipid metabolism disorders associated with dioxin exposure in a cohort of Chinese male workers revealed by a comprehensive lipidomics study. Environ Int 2021; 155:106665. [PMID: 34098336 DOI: 10.1016/j.envint.2021.106665] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 05/23/2021] [Accepted: 05/23/2021] [Indexed: 06/12/2023]
Abstract
Dioxins, environmentally stable and ubiquitous, have been found to induce metabolic changes especially in lipids and be related to multiple diseases. However, limited study is available on lipid alternations related to human exposure to dioxins. This study aims to explore the serum lipidomic characterization and to understand the underlying mechanisms of adverse health risks associated with dioxin exposure. A lipidomic study integrating nontargeted lipidomics, and targeted free fatty acid (FFA) and acyl-coenzyme A (acyl-CoA) analyses were conducted to investigate the 94 serum samples from two groups of male workers with remarkably different dioxin concentrations. The obtained results exhibited distinct lipidomic signatures between the high and low exposed groups. A total of 37 lipids were identified with the significant changes. The results revealed that dioxin exposure caused accumulations of triglyceride (TG), ceramide (Cer) and sphingoid (So), remodeling of glycerophospholipid (GP), imbalanced FFA metabolism, as well as upregulation of platelet-activating factor (PAF). These findings implied the associations between dioxin exposure and potential adverse health risks including inflammation, apoptosis, cardiovascular diseases (CVDs), and liver diseases. This study is the first to explain the associations between dioxin exposure and health effects at the level of lipid metabolism.
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Affiliation(s)
- Yanshan Liang
- Beijing Normal University-Hong Kong Baptist University United International College, Zhuhai, China; State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong Special Administrative Region
| | - Zhi Tang
- Shenzhen Center for Disease Control and Prevention, Shenzhen 518055, China; Department of Environmental and Occupational Health, School of Public Health, Guangdong Medical University, Dongguan, China
| | - Yousheng Jiang
- Shenzhen Center for Disease Control and Prevention, Shenzhen 518055, China
| | - Chunyan Ai
- Shenzhen Center for Disease Control and Prevention, Shenzhen 518055, China
| | - Jinling Peng
- Shenzhen Center for Disease Control and Prevention, Shenzhen 518055, China
| | - Yuan Liu
- Shenzhen Center for Disease Control and Prevention, Shenzhen 518055, China
| | - Jinru Chen
- Songgang Preventive Health Center of Baoan District, Shenzhen, 518105, China
| | - Xiong Xin
- Beijing Normal University-Hong Kong Baptist University United International College, Zhuhai, China
| | - Bo Lei
- Beijing Normal University-Hong Kong Baptist University United International College, Zhuhai, China
| | - Jianqing Zhang
- Shenzhen Center for Disease Control and Prevention, Shenzhen 518055, China.
| | - Zongwei Cai
- Beijing Normal University-Hong Kong Baptist University United International College, Zhuhai, China; State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong Special Administrative Region.
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Jiang Y, Ai C, Liu Y, Peng J, Lin X, Zhou J, Liu S, Zhang J. [Establishment the method for polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans determination in human serum]. Wei Sheng Yan Jiu 2021; 50:104-110. [PMID: 33517970 DOI: 10.19813/j.cnki.weishengyanjiu.2021.01.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
OBJECTIVE To establish the determination method for polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans(PCDD/Fs) in human serum, and further to provide an operable and scientific determination protocal and basis for conducting human health risk assessment for PCDD/Fs. METHODS The serum samples were pretreated by C18 column solid phase extraction, acid silica gel column and activated carbon column purification, separated by DB-5 MS capillary column(60 m×0. 25 mm×0. 25 μm), and PCDD/Fs was quantitative analyzed by high resolution mass spectrometry. RESULTS The method detection limit was in the range of 0. 35-3. 26 pg/g lipid. This method was further validated using international serum standard reference material sample SRM 1958. According to the reference mass fraction values given for SRM 1958, the concentrations of 17 PCDD/Fs monomers were all in the range of reference mass fraction values, and the relative standard deviation was 2%-19%(n=3). This method was further applied to determination PCDD/Fs in actual serum of human body. The result showed that the recovery rate of isotope labeled PCDD/Fs internal standards were in the range of 61%-135%. CONCLUSION The performance of the method is highly sensitive, stable and highly accurate, which meets the requirements for the determination of PCDD/Fs in human serum and the method can be applied to human health risk assessment for PCDD/Fs in the future.
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Affiliation(s)
- Yousheng Jiang
- Shenzhen Center for Disease Control and Prevention, Laboratory of Persistent Organic Pollutants, Shenzhen 518055, China
| | - Chunyan Ai
- Shenzhen Center for Disease Control and Prevention, Laboratory of Persistent Organic Pollutants, Shenzhen 518055, China Shenzhen Maternal and Child Health Care Hospital, Shenzhen 518000, China
| | - Yuan Liu
- Shenzhen Center for Disease Control and Prevention, Laboratory of Persistent Organic Pollutants, Shenzhen 518055, China
| | - Jinling Peng
- Shenzhen Center for Disease Control and Prevention, Laboratory of Persistent Organic Pollutants, Shenzhen 518055, China
| | - Xiaoshi Lin
- Shenzhen Center for Disease Control and Prevention, Laboratory of Persistent Organic Pollutants, Shenzhen 518055, China
| | - Jian Zhou
- Shenzhen Center for Disease Control and Prevention, Laboratory of Persistent Organic Pollutants, Shenzhen 518055, China
| | - Si Liu
- Shenzhen Center for Disease Control and Prevention, Laboratory of Persistent Organic Pollutants, Shenzhen 518055, China
| | - Jianqing Zhang
- Shenzhen Center for Disease Control and Prevention, Laboratory of Persistent Organic Pollutants, Shenzhen 518055, China
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Yuan S, Yu Q, Wang S, Xu Y, Ge H, Wang J, Zhang S, Chen W, Li J, Song Q, GU W, Yan J, Li X, Wang J, Zhang H, Huang D, Wang B, Ai C, Zhao L, Song Y, Yu J. Individualized Adaptive Radiotherapy versus Standard Radiotherapy with Chemotherapy for Patients with Locally Advanced Non-Small Cell Lung Cancer: A Multicenter Randomized Phase III Clinical Trial CRTOG1601. Int J Radiat Oncol Biol Phys 2020. [DOI: 10.1016/j.ijrobp.2020.07.2286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Liang Y, Tang Z, Jiang Y, Ai C, Peng J, Liu Y, Chen J, Zhang J, Cai Z. Serum metabolic changes associated with dioxin exposure in a Chinese male cohort. Environ Int 2020; 143:105984. [PMID: 32712422 DOI: 10.1016/j.envint.2020.105984] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Revised: 07/03/2020] [Accepted: 07/13/2020] [Indexed: 06/11/2023]
Abstract
Dioxins, a group of persistent organic pollutants, have been proved to correlate with ranges of diseases by activating the aryl hydrocarbon receptor (AhR). However, previous dioxin toxicity studies primarily focused on the activation of AhR with signaling pathways at gene and protein levels. The investigation of underlying mechanisms at the metabolic level is still necessary. In this study, serum samples of 48 and 47 healthy participants with the highest and lowest dioxin levels based on quartile distribution of the serum dioxin concentrations of 215 male adults were selected for metabolomics analysis by using liquid chromatography coupled with orbitrap high-resolution mass spectrometry to investigate dioxin-related metabolic responses. The identified potential biomarkers included acylcarnitines, fatty acids and derivatives, glycerophospholipids, etc. suggested that metabolic pathways such as fatty acid β-oxidation, essential fatty acid metabolism, arachidonic acid metabolism, glycerophospholipid and sphingolipid metabolism and purine metabolism were disturbed by dioxin exposure. The results indicated that people with high dioxin exposure levels were at the potential health risks of inflammation, liver and cardiovascular diseases. The metabolic findings may help understand the link between dioxin exposure and the diseases.
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Affiliation(s)
- Yanshan Liang
- Beijing Normal University-Hong Kong Baptist University United International College, Zhuhai, China; State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong Special Administrative Region; Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Zhi Tang
- Shenzhen Center for Disease Control and Prevention, Shenzhen, China; Department of Environmental and Occupational Health, School of Public Health, Guangdong Medical University, Dongguan, China
| | - Yousheng Jiang
- Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Chunyan Ai
- Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Jinling Peng
- Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Yuan Liu
- Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Jinru Chen
- Songgang Preventive Health Center of Baoan District, Shenzhen, China
| | - Jianqing Zhang
- Shenzhen Center for Disease Control and Prevention, Shenzhen, China.
| | - Zongwei Cai
- Beijing Normal University-Hong Kong Baptist University United International College, Zhuhai, China; State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong Special Administrative Region.
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Zhang Q, Ai C, Wang G, Liu X, Tian F, Zhao J, Zhang H, Chen Y, Chen W. Oral application of lactic acid bacteria following treatment with antibiotics inhibits allergic airway inflammation. J Appl Microbiol 2015; 119:809-17. [DOI: 10.1111/jam.12885] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2014] [Revised: 05/20/2015] [Accepted: 05/21/2015] [Indexed: 12/26/2022]
Affiliation(s)
- Q. Zhang
- State Key Laboratory of Food Science and Technology; School of Food Science and Technology; Jiangnan University; Wuxi Jiangsu China
| | - C. Ai
- State Key Laboratory of Food Science and Technology; School of Food Science and Technology; Jiangnan University; Wuxi Jiangsu China
| | - G. Wang
- State Key Laboratory of Food Science and Technology; School of Food Science and Technology; Jiangnan University; Wuxi Jiangsu China
| | - X. Liu
- State Key Laboratory of Food Science and Technology; School of Food Science and Technology; Jiangnan University; Wuxi Jiangsu China
| | - F. Tian
- State Key Laboratory of Food Science and Technology; School of Food Science and Technology; Jiangnan University; Wuxi Jiangsu China
| | - J. Zhao
- State Key Laboratory of Food Science and Technology; School of Food Science and Technology; Jiangnan University; Wuxi Jiangsu China
| | - H. Zhang
- State Key Laboratory of Food Science and Technology; School of Food Science and Technology; Jiangnan University; Wuxi Jiangsu China
| | - Y.Q. Chen
- State Key Laboratory of Food Science and Technology; School of Food Science and Technology; Jiangnan University; Wuxi Jiangsu China
| | - W. Chen
- State Key Laboratory of Food Science and Technology; School of Food Science and Technology; Jiangnan University; Wuxi Jiangsu China
- Beijing Innovation Centre of Food Nutrition and Human Health; Beijing Technology & Business University; Beijing 100048 China
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Wen X, Chen L, Ai C, Zhou Z, Jiang H. Variation in lipid composition of Chinese mitten-handed crab, Eriocheir sinensis during ovarian maturation. Comp Biochem Physiol B Biochem Mol Biol 2001; 130:95-104. [PMID: 11470448 DOI: 10.1016/s1096-4959(01)00411-0] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
This experiment was conducted to investigate the variation in lipid composition during the ovarian maturation of the crab Eriocheir sinensis. The Chinese mitten-handed crab broodstock was divided into six different maturation periods according to the size and color of ovary. Ovary, hepatopancreas, muscle, and hemolymph of broodstock in different maturation periods were analyzed for total lipid and fatty acids using gas chromatography, and lipid classes by thin-layer chromatography. The ovarian lipid concentration (expressed as percent wet ovarian weight) increased steadily from stage II (5.4%) to stage IV (19.1%), and decreased to the lowest levels after spawning (stage V, 6.6%). The hepatopancreatic lipid concentration (expressed as percent wet hepatopancreatic weight) increased with maturity of the ovaries, reached a maximum at stage III(2) (29.9%), and decreased during the subsequent period to spawning (16.7%). The muscular and hemolymph lipid concentration did not change markedly during the ovarian development. These results suggest the possible movement of hepatopancreatic lipids to the ovaries during the ovarian maturation. Both triacylglycerol and phosphatidylcholine were responsible for the increase in ovarian lipid concentration during sexual maturation. The fatty acids of total lipid, triacylglycerol, and phosphatidylcholine of the ovaries did not vary systematically during the ovarian maturation, but the ratio between n-3PUFA (polyunsaturated fatty acid) and n-6PUFA did change regularly with the ovarian lipid. These suggest that enough PUFA, especially n-3PUFA, should be supplied to the crab during ovarian maturation.
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Affiliation(s)
- X Wen
- Department of Biology, East China Normal University, 200062, Shanghai, PR China.
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Abstract
Economists often estimate models with a log-transformed dependent variable. The results from the log-transformed model are often retransformed back to the unlogged scale. Other studies have shown how to obtain consistent estimates on the original scale but have not provided variance equations for those estimates. In this paper, we derive the variance for three estimates--the conditional mean of y, the slope of y, and the average slope of y--on the retransformed scale. We then illustrate our proposed procedures with skewed health expenditure data from a sample of Medicaid eligible patients with severe mental illness.
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Affiliation(s)
- C Ai
- University of Florida, USA
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Sarkar PS, Appukuttan B, Han J, Ito Y, Ai C, Tsai W, Chai Y, Stout JT, Reddy S. Heterozygous loss of Six5 in mice is sufficient to cause ocular cataracts. Nat Genet 2000; 25:110-4. [PMID: 10802668 DOI: 10.1038/75500] [Citation(s) in RCA: 150] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Myotonic dystrophy (DM) is an autosomal dominant disorder characterized by skeletal muscle wasting, myotonia, cardiac arrhythmia, hyperinsulinaemia, mental retardation and ocular cataracts. The genetic defect in DM is a CTG repeat expansion located in the 3' untranslated region of DMPK and 5' of a homeodomain-encoding gene, SIX5 (formerly DMAHP; refs 2-5). There are three mechanisms by which CTG expansion can result in DM. First, repeat expansion may alter the processing or transport of the mutant DMPK mRNA and consequently reduce DMPK levels. Second, CTG expansion may establish a region of heterochromatin 3' of the repeat sequence and decrease SIX5 transcription. Third, toxic effects of the repeat expansion may be intrinsic to the repeated elements at the level of DNA or RNA (refs 10,11). Previous studies have demonstrated that a dose-dependent loss of Dm15 (the mouse DMPK homologue) in mice produces a partial DM phenotype characterized by decreased development of skeletal muscle force and cardiac conduction disorders. To test the role of Six5 loss in DM, we have analysed a strain of mice in which Six5 was deleted. Our results demonstrate that the rate and severity of cataract formation is inversely related to Six5 dosage and is temporally progressive. Six5+/- and Six5-/- mice show increased steady-state levels of the Na+/K+-ATPase alpha-1 subunit and decreased Dm15 mRNA levels. Thus, altered ion homeostasis within the lens may contribute to cataract formation. As ocular cataracts are a characteristic feature of DM, these results demonstrate that decreased SIX5 transcription is important in the aetiology of DM. Our data support the hypothesis that DM is a contiguous gene syndrome associated with the partial loss of both DMPK and SIX5.
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Affiliation(s)
- P S Sarkar
- Institute for Genetic Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
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Abstract
A Fizeau interferometer utilizes a multimode laser as a light source for testing thin transparent plate samples. As a result of multimode linear laser operation, interference fringes are obtained only when the optical path difference between two surfaces is equal to twice a multiple of the laser's effective cavity length. For three parallel surfaces, we can either adjust their separations or select a laser such that only two of the three surfaces meet the requirement of twice a multiple of the laser's effective cavity length.
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Abstract
Multiple reflections between two surfaces of a window introduce a fixed pattern error in optical measurements. One way to remove these spurious reflections is to use a reasonably large wedge so that the interference fringes formed by the two surfaces are too dense for the detector to resolve. However, this method does not work if the wedge angle is small, e.g., several arcseconds. By tilting both the window and the return mirror properly, it is possible to remove the effect of multiple reflections of a window. Theory and experimental results are presented.
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Abstract
We describe a modified three-flat method. In a Cartesian coordinate system, a flat can be expressed as the sum of even-odd, odd-even, even-even, and odd-odd functions. The even-odd and the odd-even functions of each flat are obtained first, and then the even-even function is calculated. All three functions are exact. The odd-odd function is difficult to obtain. In theory, this function can be solved by rotating the flat 90°, 45°, 22.5°, etc. The components of the Fourier series of this odd-odd function are derived and extracted from each rotation of the flat. A flat is approximated by the sum of the first three functions and the known components of the odd-odd function. In the experiments, the flats are oriented in six configurations by rotating the flats 180°, 90°, and 45° with respect to one another, and six measurements are performed. The exact profiles along every 45° diameter are obtained, and the profile in the area between two adjacent diameters of these diameters is also obtained with some approximation. The theoretical derivation, experiment results, and error analysis are presented.
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Abstract
Phase errors in a Fizeau phase-shifting interferometer caused by multiple-reflected beams from a retroreflective optics, such as a corner cube and a right-angle prism, are studied. Single- and double-pass configurations are presented, and their measurement results are compared. An attenuator is not needed in a double-pass configuration because light is reflected by the retroreflective optics twice and the reference surface once and hence the intensities match. It is more accurate to test a corner cube or a right-angle prism in a double-pass configuration than in a single-pass configuration. Simulations and experimental results are presented.
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Abstract
We describe a sensitive method for measuring the stress birefringence of an optical window that utilizes a phase-measuring Fizeau interferometer incorporating a variable retarder and a nonpolarizing beam splitter. When we test a material in an interferometer cavity, the wave front transmitted through the material is deviated by the surfaces, inhomogeneity, and birefringence of the material. Birefringence causes the transmitted wave front to have different optical path difference (OPD) profiles for the vertical and horizontal orientations of linear polarization. Subtracting these OPD profiles reveals the amount of phase difference between the fast and slow axes of the material. Hence, birefringence may be calculated. Phase-measurement techniques and a computer-controlled interferometer employing a variable liquid-crystal retarder provide a fully automated instrument for measuring stress birefringence. The theoretical derivation, discussion of the instrument, and experimental results are presented.
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Abstract
The alignment of a corner cube affects the measurement of its dihedral angle. For 5 deg of tilt, the error is up to 7%, depending on the orientation of the tilt. A vector model is devised to derive formulas that take misalignment into account for both solid and hollow corner cubes. When the wave-front tilt caused by the dihedral angle error is not much greater than that caused by the surface figure, because of vignetting for a tilting illumination, the surface figure of the cube facet makes varying contributions to the wave-front tilt for different incident angles. Simulations and experimental results are presented.
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Abstract
The phase errors caused by spurious reflection in Twyman-Green and Fizeau interferometers are studied. A practical algorithm effectively eliminating the error is presented. Two other algorithms are reviewed, and the results obtained using the three algorithms are compared.
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Abstract
If the nonlinearity of the motion of a piezoelectric transducer (PZT) can be described as a quadratic function, the integrated intensity of one frame in phase shift interferometry can be calculated using the Fresnel integral. For a PZT with smaller nonlinearity, the rms phase error is almost linearly proportional to the quadratic coefficient The effects of PZT nonlinearity on the three- and the four-bucket algorithms are compared.
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