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Distinguishing IDH mutation status in gliomas using FTIR-ATR spectra of peripheral blood plasma indicating clear traces of protein amyloid aggregation. BMC Cancer 2024; 24:222. [PMID: 38365669 PMCID: PMC10870484 DOI: 10.1186/s12885-024-11970-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Accepted: 02/06/2024] [Indexed: 02/18/2024] Open
Abstract
BACKGROUND Glioma is a primary brain tumor and the assessment of its molecular profile in a minimally invasive manner is important in determining treatment strategies. Among the molecular abnormalities of gliomas, mutations in the isocitrate dehydrogenase (IDH) gene are strong predictors of treatment sensitivity and prognosis. In this study, we attempted to non-invasively diagnose glioma development and the presence of IDH mutations using multivariate analysis of the plasma mid-infrared absorption spectra for a comprehensive and sensitive view of changes in blood components associated with the disease and genetic mutations. These component changes are discussed in terms of absorption wavenumbers that contribute to differentiation. METHODS Plasma samples were collected at our institutes from 84 patients with glioma (13 oligodendrogliomas, 17 IDH-mutant astrocytoma, 7 IDH wild-type diffuse glioma, and 47 glioblastomas) before treatment initiation and 72 healthy participants. FTIR-ATR spectra were obtained for each plasma sample, and PLS discriminant analysis was performed using the absorbance of each wavenumber in the fingerprint region of biomolecules as the explanatory variable. This data was used to distinguish patients with glioma from healthy participants and diagnose the presence of IDH mutations. RESULTS The derived classification algorithm distinguished the patients with glioma from healthy participants with 83% accuracy (area under the curve (AUC) in receiver operating characteristic (ROC) = 0.908) and diagnosed the presence of IDH mutation with 75% accuracy (AUC = 0.752 in ROC) in cross-validation using 30% of the total test data. The characteristic changes in the absorption spectra suggest an increase in the ratio of β-sheet structures in the conformational composition of blood proteins of patients with glioma. Furthermore, these changes were more pronounced in patients with IDH-mutant gliomas. CONCLUSIONS The plasma infrared absorption spectra could be used to diagnose gliomas and the presence of IDH mutations in gliomas with a high degree of accuracy. The spectral shape of the protein absorption band showed that the ratio of β-sheet structures in blood proteins was significantly higher in patients with glioma than in healthy participants, and protein aggregation was a distinct feature in patients with glioma with IDH mutations.
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Mid-infrared photoacoustic spectroscopy based on ultrasound detection for blood component analysis. BIOMEDICAL OPTICS EXPRESS 2023; 14:3841-3852. [PMID: 37497499 PMCID: PMC10368030 DOI: 10.1364/boe.494615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 06/21/2023] [Accepted: 06/22/2023] [Indexed: 07/28/2023]
Abstract
For the non-invasive measurement of biological tissue, a piezoelectric photoacoustic spectroscopy (PZT-PAS) system that detects a single frequency of ultrasound induced by the irradiation of pulse-modulated mid-infrared laser light was developed. PA spectra of the optical phantom and biological samples were obtained, and the relationship between the PA signal intensity and optical absorbance in the fingerprint region (930-1,200 cm-1) was analyzed to estimate the optical absorbance. The resonance vibration of the induced ultrasound was utilized to further increase the signal strength for biological tissue measurement. Consequently, PA spectrum reflecting the absorption of components in biological tissues was obtained.
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Terahertz fiber link using dielectric silicon waveguide interface. OPTICS EXPRESS 2023; 31:7351-7362. [PMID: 36859868 DOI: 10.1364/oe.482785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 01/29/2023] [Indexed: 06/18/2023]
Abstract
Nascent data-intensive emerging technologies are mandating low-loss, short-range interconnects, whereas existing interconnects suffer from high losses and low aggregate data throughput owing to a lack of efficient interfaces. Here, we report an efficient 22-Gbit/s terahertz fiber link using a tapered silicon interface that serves as a coupler between the dielectric waveguide and hollow core fiber. We investigated the fundamental optical properties of hollow-core fibers by considering fibers with 0.7-mm and 1-mm core diameters. We achieved a coupling efficiency of ∼ 60% with a 3-dB bandwidth of 150 GHz in the 0.3-THz band over a 10 cm fiber.
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Mid-infrared laser heterodyne spectrometer by hollow optical fiber and its newly designed coupler. APPLIED OPTICS 2023; 62:A31-A36. [PMID: 36821297 DOI: 10.1364/ao.475426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 11/21/2022] [Indexed: 06/18/2023]
Abstract
We demonstrate a newly designed, to the best of our knowledge, hollow optical fiber coupler for a mid-infrared (IR) laser heterodyne spectrometer that mixes a targeted light source with local oscillator (LO) light. The hollow fiber achieves a high transmission efficiency ∼80-90%/m, not only for a coherent laser source but also for an incoherent blackbody source. The branching characteristics of the hollow optical fiber coupler are found to be strongly dependent on the curvature and length of the input port fiber, indicating that the branching ratio could be designed independently for each input port. Our laboratory measurements demonstrate that the branching ratio and transmittance of the coupler can be varied by coupling a flexible fiber to the input side owing to the excitation of higher-order modes. Using the hollow optical fiber coupler, a high-resolution emission spectrum of the quantum cascade laser at 10.3 µm for our C O 2 laser-based heterodyne spectrometer is successfully achieved. Using a C O 2 laser with a hollow fiber and a blackbody as a direct input signal in free space, we obtain the sensitivity performance of IR laser heterodyne spectrometer as 2000-3000 K of the system noise temperature. This suggests that the transmission of a coherent LO laser through a hollow optical fiber has almost the same sensitivity for the IR heterodyne detection as that without a fiber.
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EP02.01-006 Advances in the Treatment of Postoperative Recurrence of Non-Small Cell Lung Cancer and Their Real-World Impact on Survival. J Thorac Oncol 2022. [DOI: 10.1016/j.jtho.2022.07.333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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EP02.01-014 Prognostic Classification of Early-Stage Lung Cancer Using Preoperative Prealbumin and D-dimer Levels. J Thorac Oncol 2022. [DOI: 10.1016/j.jtho.2022.07.341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Evaluation of Suture Elongation of Flexor Tendons using the Pulvertaft Method: a Biomechanical Study using Cadaveric Specimens. Muscles Ligaments Tendons J 2022. [DOI: 10.32098/mltj.02.2022.19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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P53.04 Local Therapies vs. Specific TKIs as the Initial Treatment for Oligo-Recurrent Lung Adenocarcinoma With Driver Mutations. J Thorac Oncol 2021. [DOI: 10.1016/j.jtho.2021.08.553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Vacuum Ultraviolet Absorption Spectroscopy Analysis of Breath Acetone Using a Hollow Optical Fiber Gas Cell. SENSORS 2021; 21:s21020478. [PMID: 33445436 PMCID: PMC7827082 DOI: 10.3390/s21020478] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/06/2021] [Accepted: 01/08/2021] [Indexed: 02/02/2023]
Abstract
Human breath is a biomarker of body fat metabolism and can be used to diagnose various diseases, such as diabetes. As such, in this paper, a vacuum ultraviolet (VUV) spectroscopy system is proposed to measure the acetone in exhaled human breath. A strong absorption acetone peak at 195 nm is detected using a simple system consisting of a deuterium lamp source, a hollow-core fiber gas cell, and a fiber-coupled compact spectrometer corresponding to the VUV region. The hollow-core fiber functions both as a long-path and an extremely small-volume gas cell; it enables us to sensitively measure the trace components of exhaled breath. For breath analysis, we apply multiple regression analysis using the absorption spectra of oxygen, water, and acetone standard gas as explanatory variables to quantitate the concentration of acetone in breath. Based on human breath, we apply the standard addition method to obtain the measurement accuracy. The results suggest that the standard deviation is 0.074 ppm for healthy human breath with an acetone concentration of around 0.8 ppm and a precision of 0.026 ppm. We also monitor body fat burn based on breath acetone and confirm that breath acetone increases after exercise because it is a volatile byproduct of lipolysis.
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A Compact Mid-Infrared Spectroscopy System for Healthcare Applications Based on a Wavelength-Swept, Pulsed Quantum Cascade Laser. SENSORS (BASEL, SWITZERLAND) 2020; 20:s20123438. [PMID: 32570744 PMCID: PMC7349820 DOI: 10.3390/s20123438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/16/2020] [Accepted: 06/16/2020] [Indexed: 06/11/2023]
Abstract
A mid-infrared spectroscopic system using a high-speed wavelength-swept and pulsed quantum cascade laser (QCL) for healthcare applications such as blood glucose measurement is proposed. We developed an attenuated total reflection measurement system comprising the QCL with a micro-electromechanical system (MEMS)-scanning grating, hollow optical fibers, and InAsSb detector and tested its feasibility for healthcare applications. A continuous spectrum was obtained by integrating comb-shaped spectra, the timing of which was slightly shifted. As this method does not require complex calculations, absorption spectra are obtained in real-time. We found that the signal-to-noise ratio of the obtained spectrum had been improved by increasing the number of spectra that were integrated into the spectrum calculation. Accordingly, we succeeded in measuring the absorption spectrum of a 0.1% aqueous glucose solution. Furthermore, the absorption spectra of human lips were measured, and it was shown that estimation of blood glucose levels were possible using a model equation derived using a partial least squares regression analysis of the measured absorption spectra. The spectroscopic system based on the QCL with MEMS-scanning grating has the advantages of compactness and low cost over conventional Fourier transform infrared-based systems and common spectroscopic systems with a tunable QCL that has a relatively large, movable grating.
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P1.17-06 Long-Term Oncological Outcome After Thoracoscopic Lobectomy for Non-Small Cell Lung Cancer Patients. J Thorac Oncol 2019. [DOI: 10.1016/j.jtho.2019.08.1280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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MA18.03 Distinction Between Primary Lung Cancer and Pulmonary Metastasis of Esophageal Cancer Using the Nanostring nCounter System. J Thorac Oncol 2019. [DOI: 10.1016/j.jtho.2019.08.648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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P2.13-14 The Utility of Three-Dimensional CT for Prediction of Tumor Invasiveness in Clinical IA Lung Acenocarcinoma. J Thorac Oncol 2019. [DOI: 10.1016/j.jtho.2019.08.1785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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P1.09-20 Significance of Maximal Diameter Measurement in Small-Sized Adenocarcinomas. J Thorac Oncol 2019. [DOI: 10.1016/j.jtho.2019.08.1049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Alkaline extracellular conditions promote the proliferation and mineralization of a human cementoblast cell line. Int Endod J 2018; 52:639-645. [PMID: 30447154 DOI: 10.1111/iej.13044] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 11/13/2018] [Indexed: 01/10/2023]
Abstract
AIM To investigate the proliferation and mineralization of a human cementoblast cell line under alkaline conditions. METHODOLOGY A human cementoblast cell line was cultured in alkaline media with several pHs (pH 7.6, 8.0 and 8.4) without CO2 . Cell numbers, phospho-p44/42 expression, alkaline phosphatase (ALP) activity and mineralization were evaluated. The significance of differences between groups was assessed using two-way analysis of variance 15 (ANOVA) followed by Bonferroni's multiple comparison test (α = 0.01). RESULTS Cell numbers increased in a time-dependent manner in the high pH medium groups. Western blot analysis revealed the upregulated expression of phospho-p44/42 under alkaline conditions. ALP activity was also increased at pH 8.0 and 8.4. Alizarin red staining revealed increased mineralization in the high pH medium groups. The incorporation of the transient receptor potential ankyrin subfamily member 1 (TRPA1) antagonist HC030031 markedly negated the effect on proliferation and mineralization. CONCLUSIONS Extracellular alkaline conditions promoted the proliferation and mineralization of human cementoblasts in vitro via TRPA1.
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P1.11-07 Utility of the Maximum CT Value in Predicting Invasiveness of Pure GGNs. J Thorac Oncol 2018. [DOI: 10.1016/j.jtho.2018.08.823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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The effect of femoral bone tunnel configuration on tendon-bone healing in an anterior cruciate ligament reconstruction: An animal study. Bone Joint Res 2018; 7:327-335. [PMID: 29922452 PMCID: PMC5987692 DOI: 10.1302/2046-3758.75.bjr-2017-0238.r2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Objectives To compare the effect of femoral bone tunnel configuration on tendon-bone healing in an anterior cruciate ligament (ACL) reconstruction animal model. Methods Anterior cruciate ligament reconstruction using the plantaris tendon as graft material was performed on both knees of 24 rabbits (48 knees) to mimic ACL reconstruction by two different suspensory fixation devices for graft fixation. For the adjustable fixation device model (Socket group; group S), a 5 mm deep socket was created in the lateral femoral condyle (LFC) of the right knee. For the fixed-loop model (Tunnel group; group T), a femoral tunnel penetrating the LFC was created in the left knee. Animals were sacrificed at four and eight weeks after surgery for histological evaluation and biomechanical testing. Results Histologically, both groups showed a mixture of direct and indirect healing patterns at four weeks, whereas only indirect healing patterns were observed in both groups at eight weeks. No significant histological differences were seen between the two groups at four and eight weeks in the roof zone (four weeks, S: mean 4.8 sd 1.7, T: mean 4.5 sd 0.5, p = 0.14; eight weeks, S: mean 5.8 sd 0.8, T: mean 4.8 sd 1.8, p = 0.88, Mann-Whitney U test) or side zone (four weeks, S: mean 5.0 sd 1.2, T: mean 4.8 sd 0.4, p = 0.43; eight weeks, S: mean 5.3 sd 0.8,T: mean 5.5 sd 0.8, p = 0.61, Mann-Whitney U test) . Similarly, no significant difference was seen in the maximum failure load between group S and group T at four (15.6 sd 9.0N and 13.1 sd 5.6N) or eight weeks (12.6 sd 3.6N and 17.1 sd 6.4N, respectively). Conclusion Regardless of bone tunnel configuration, tendon-bone healing after ACL reconstruction primarily occurred through indirect healing. No significant histological or mechanical differences were observed between adjustable and fixed-loop femoral cortical suspension methods. Cite this article: Y. Sato, R. Akagi, Y. Akatsu, Y. Matsuura, S. Takahashi, S. Yamaguchi, T. Enomoto, R. Nakagawa, H. Hoshi, T. Sasaki, S. Kimura, Y. Ogawa, A. Sadamasu, S. Ohtori, T. Sasho. The effect of femoral bone tunnel configuration on tendon-bone healing in an anterior cruciate ligament reconstruction: An animal study. Bone Joint Res 2018;7:327–335. DOI: 10.1302/2046-3758.75.BJR-2017-0238.R2.
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Noninvasive glucose monitoring using mid-infrared absorption spectroscopy based on a few wavenumbers. BIOMEDICAL OPTICS EXPRESS 2018; 9:289-302. [PMID: 29359104 PMCID: PMC5772583 DOI: 10.1364/boe.9.000289] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 12/10/2017] [Accepted: 12/18/2017] [Indexed: 05/03/2023]
Abstract
A method for performing noninvasive blood glucose measurements was developed. The method is based on mid-infrared absorption spectroscopy and uses only a few wavenumbers to measure blood glucose levels in vivo unconditionally. We found that the regression of blood glucose levels using only three wavenumbers, which were selected using a series cross-validation technique, realized accuracies comparable to those of cases in which a greater number of wavenumbers are used. In addition, we demonstrated the performance of this model through correlations among different types of data.
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Robustness of adult female survival maintains a high-density sika deer (Cervus nippon) population following the initial irruption. WILDLIFE RESEARCH 2018. [DOI: 10.1071/wr17103] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Context Irruption of large herbivore populations is characterised by three distinct phases: (1) an exponential increase in population to a peak abundance; (2) a population crash; and (3) a second increase to another population peak, typically lower than the first peak of abundance. However, there has been little study of age- and sex-specific factors that affect the post-initial irruption interactions with food sources. Aims We aimed to investigate annual survival rates of sika deer (Cervus nippon Temminck, 1838) in the sequent irruption of a population on Nakanoshima Island, Lake Toya, Japan, with a chronically high density during the period 2002–12. Methods Survival monitoring data were obtained for 219 individuals (93 males and 126 females) using radio-collars. Annual survival was quantified, and related factors, i.e. deer abundance and winter severity, were determined by model selection using Akaike information criterion values. Key Results The results showed that annual survival rates across sexes and age classes (fawn, yearling, prime-aged, old) decreased with increasing population density, snow depth and winter precipitation. Winter severity had a greater effect on adult survival than density regulation. Nevertheless, female adult survival was maintained at a high level, with a mean of 0.84 (95% CI: 0.80–0.88). Key conclusions Robust survival rates for adult females might contribute to the maintenance of a high-density sika deer population in the post-initial irruption. Implications We suggest that in the absence of predation and hunting, sika deer population is not able to self-regulate to the density level that avoids an irreversible impact on plants.
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P2.16-016 Surgical Treatment of Indeterminate Lung Nodules. J Thorac Oncol 2017. [DOI: 10.1016/j.jtho.2017.09.1425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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P3.13-009 Rapid Detection of Lung Cancer by Fluorescent Imaging Using A γ-Glutamyltranspeptidase-Activatable Fluorescent Probe. J Thorac Oncol 2017. [DOI: 10.1016/j.jtho.2017.09.1743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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P1.13-005 Is Tumor Size for the T4 Descriptor in Lung Cancer Staging Appropriate? J Thorac Oncol 2017. [DOI: 10.1016/j.jtho.2017.09.1012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Abstract
OBJECTIVE The aim of this report was to evaluate the impact of hormone replacement therapy (HRT) on lymphocytic infiltration of the endometrium in postmenopausal women. METHOD This study included 58 Japanese patients who had undergone hysterectomy at the University Hospital of Occupational and Environmental Health, Japan. Before surgery, nine patients had received 17β-estradiol (E2), 0.72 mg transdermally for 2-8 weeks (E2 group); 16 patients had received an Estra-1,3,5(10)-triene-3,16α, 17β-triol (E3) vaginal tablet 0.5 mg per month five times (E3 group); and 19 patients had received 17β-estradiol, 0.62 mg, and norethindrone acetate (P), 2.70 mg for 3-16 weeks (E2 + P group). Fourteen patients received no HRT (control group). We examined uterine tissue specimens immunohistochemically for CD45+, CD3+, CD4+, CD8+, CD20+, CD56+, and Ki67 antigen-positive cells. RESULTS The numbers of CD56 + cells were significantly increased in the E2 group compared with all other groups (E2 vs. E3: 7.0 vs. 0.75, p = 0.017; E2 vs. E2 + P: 7.0 vs. 0.58, p = 0.009; E2 vs. CONTROL 7.0 vs. 0.43, p = 0.010). The numbers of CD3+ cells were significantly increased in the E2 group compared with the control group (149.3 vs. 42.6, p = 0.008). CONCLUSION 17β-Estradiol induced the proliferation of endometrial uterine natural killer cells (CD56+) in postmenopausal women.
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P6255Temporal trends of incidence and clinical features of acute myocardial infarction in a Japanese rural area from 2006 to 2014. Eur Heart J 2017. [DOI: 10.1093/eurheartj/ehx493.p6255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Real-Time Analysis of Isoprene in Breath by Using Ultraviolet-Absorption Spectroscopy with a Hollow Optical Fiber Gas Cell. SENSORS 2016; 16:s16122058. [PMID: 27929387 PMCID: PMC5191039 DOI: 10.3390/s16122058] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 11/28/2016] [Accepted: 11/30/2016] [Indexed: 12/24/2022]
Abstract
A breath analysis system based on ultraviolet-absorption spectroscopy was developed by using a hollow optical fiber as a gas cell for real-time monitoring of isoprene in breath. The hollow optical fiber functions as an ultra-small-volume gas cell with a long path. The measurement sensitivity of the system was evaluated by using nitric-oxide gas as a gas sample. The evaluation result showed that the developed system, using a laser-driven, high-intensity light source and a 3-m-long, aluminum-coated hollow optical fiber, could successfully measure nitric-oxide gas with a 50 ppb concentration. An absorption spectrum of a breath sample in the wavelength region of around 200–300 nm was measured, and the measured spectrum revealed the main absorbing components in breath as water vapor, isoprene, and ozone converted from oxygen by radiation of ultraviolet light. The concentration of isoprene in breath was estimated by multiple linear regression. The regression analysis results showed that the proposed analysis system enables real-time monitoring of isoprene during the exhaling of breath. Accordingly, it is suitable for measuring the circadian variation of isoprene.
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Gas viscosity measurement with diamagnetic-levitation viscometer based on electromagnetically spinning system. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:125105. [PMID: 28040965 DOI: 10.1063/1.4968026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Utilizing a graphite-disk probe attached with a thin aluminum disk, we have developed a friction-free viscosity measurement system. The probe is levitated above a NdFeB magnet because of diamagnetic effect and rotated by an electromagnetically induced torque. The probe is absolutely free form mechanical friction, and therefore, the accurate measurements of the viscosity of gases can be achieved. To demonstrate the accuracy and sensitivity of our method, we measured the viscosity of 8 kinds of gases and its temperature change from 278 K to 318 K, and we confirmed a good agreement between the obtained values and literature values. This paper demonstrates that our method has the ability to measure the fluid viscosity in the order of μPa ⋅ s.
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Multi-element hollow-core anti-resonant fiber for infrared thermal imaging. OPTICS EXPRESS 2016; 24:26565-26574. [PMID: 27857389 DOI: 10.1364/oe.24.026565] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A bundle composed of 245 anti-resonant glass hollow optical fibers with a total diameter of 1 mm and fiber core diameter of 60 μm is fabricated for endoscopic infrared-thermal imaging. The bundle fiber shows low losses in the wavelength range of 3 to 4 μm owing to the anti-resonant effect of the thin glass wall. An image resolution of around 420 μm with a field-of-view of 3-mm diameter is obtained although crosstalk between adjacent fibers is observed. The experimental results of an imaging system using the fiber bundle with a half-ball lens at the distal end, which can be inserted into a working channel of endoscopes, are also shown.
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Hollow optical-fiber based infrared spectroscopy for measurement of blood glucose level by using multi-reflection prism. BIOMEDICAL OPTICS EXPRESS 2016; 7:701-8. [PMID: 26977373 PMCID: PMC4771482 DOI: 10.1364/boe.7.000701] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 12/27/2015] [Accepted: 01/26/2016] [Indexed: 05/14/2023]
Abstract
A mid-infrared attenuated total reflection (ATR) spectroscopy system employing hollow optical fibers and a trapezoidal multi-reflection ATR prism has been developed to measure blood glucose levels. Using a multi-reflection prism brought about higher sensitivity, and the flat and wide contact surface of the prism resulted in higher measurement reproducibility. An analysis of in vivo measurements of human inner lip mucosa revealed clear signatures of glucose in the difference spectra between ones taken during the fasting state and ones taken after ingestion of glucose solutions. A calibration plot based on the absorption peak at 1155 cm(-1) that originates from the pyranose ring structure of glucose gave measurement errors less than 20%.
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Optical-fiber-based laser-induced breakdown spectroscopy for detection of early caries. JOURNAL OF BIOMEDICAL OPTICS 2015; 20:065002. [PMID: 26039382 DOI: 10.1117/1.jbo.20.6.065002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 05/07/2015] [Indexed: 06/04/2023]
Abstract
A laser-induced breakdown spectroscopy (LIBS) system targeting for the in vivo analysis of tooth enamel is described. The system is planned to enable real-time analysis of teeth during laser dental treatment by utilizing a hollow optical fiber that transmits both Q-switched Nd:YAG laser light for LIBS and infrared Er:YAG laser light for tooth ablation. The sensitivity of caries detection was substantially improved by expanding the spectral region under analysis to ultraviolet (UV) light and by focusing on emission peaks of Zn in the UV region. Subsequently, early caries were distinguished from healthy teeth with accuracy rates above 80% in vitro.
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Infrared hollow optical fiber probes for reflectance spectral imaging. APPLIED OPTICS 2015; 54:4602-4607. [PMID: 25967522 DOI: 10.1364/ao.54.004602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 04/20/2015] [Indexed: 06/04/2023]
Abstract
Systems for infrared reflectance imaging are built with an FT-IR spectrometer, hollow optical fibers, and a high-speed infrared camera. To obtain reflectance images of biological samples, an optical fiber probe equipped with a light source at the distal end and a hybrid fiber probe composed of fibers for beam radiation and ones for image detection have been developed. By using these systems, reflectance spectral images of lipid painted on biomedical hard tissue, which provides reflectance of around 4%, are successfully acquired.
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Corrigendum to “Distribution of Abnormal Prion Protein in a Sheep affected with L-type Bovine Spongiform Encephalopathy” [Journal of Comparative Pathology, 149, 113–118]. J Comp Pathol 2014. [DOI: 10.1016/j.jcpa.2014.02.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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P-144 * PROGNOSTIC SIGNIFICANCE OF CLINICAL/PATHOLOGICAL STAGE IA NON-SMALL-CELL LUNG CANCER. Interact Cardiovasc Thorac Surg 2014. [DOI: 10.1093/icvts/ivu167.144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Crystallization and Structural Analysis of Intact Maltotetraose-forming Exo-amylase from Pseudomonas stutzeri. Biosci Biotechnol Biochem 2014; 65:222-5. [PMID: 11272837 DOI: 10.1271/bbb.65.222] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The intact maltotetraose-forming exo-amylase from Pseudomonas stutzeri (G4-1), which has a raw starch binding domain, has been crystallized. The structure was identified (PDB entry 1GCY) by the molecular replacement method using the structure of its catalytic domain (G4-2). The result showed that the raw starch binding domain is in a disordered state, the corresponding electron densities being almost invisible. Superposition of these two enzyme forms showed evidence for the possible location of the raw starch binding domain (SBD). This crystal is a novel case, in that it forms a regular lattice incorporating flexibly bound SBD in the channel of crystal packing of the catalytic domains.
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Blood glucose measurement by using hollow optical fiber-based attenuated total reflection probe. JOURNAL OF BIOMEDICAL OPTICS 2014; 19:057010. [PMID: 24849387 DOI: 10.1117/1.jbo.19.5.057010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Accepted: 05/01/2014] [Indexed: 05/14/2023]
Abstract
A noninvasive glucose monitoring system based on mid-infrared, attenuated total reflection spectroscopy using a hollow optical fiber probe is developed. Owing to the flexible fiber probe, measurement of oral mucosa, where blood capillaries are near the skin surface, is possible. Blood glucose levels are measured by detecting the peak intensity of glucose absorption bands, and the experimental results showed that the reproducibility of the measurement is high enough for monitoring blood glucose.
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Spectral broadening and temporal compression of ∼ 100 fs pulses in air-filled hollow core capillary fibers. OPTICS EXPRESS 2014; 22:1143-1151. [PMID: 24515074 DOI: 10.1364/oe.22.001143] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We experimentally study the spectral broadening of intense, ∼ 100 femtosecond laser pulses at 785 nm coupled into different kinds of hollow core capillary fibers, all filled with air at ambient pressure. Differently from observations in other gases, the spectra are broadened with a strong red-shift due to highly efficient intrapulse Raman scattering. Numerical simulations show that such spectra can be explained only by increasing the Raman fraction of the third order nonlinearity close to 100%. Experimentally, these broadened and red-shifted pulses do not generally allow for straightforward compression using, for example, standard chirped mirrors. However, using special hollow fibers that are internally coated with silver and polymer we obtain pulse durations in the sub-20 fs regime with energies up to 300 μJ.
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Management of a primary retroperitoneal mucinous cystadenocarcinoma: case report. EUR J GYNAECOL ONCOL 2014; 35:163-166. [PMID: 24772920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
PURPOSE To review the treatment of primary retroperitoneal mucinous cystadenocarcinoma (PRMC). CASE REPORT A 30-year-old woman had a large retroperitoneal mucinous adenocarcinoma treated with conservative laparoscopic surgery. Two years later, she was found to have bilateral ovarian cysts at the time of cesarean section. Since cystectomies revealed mucinous adenocarcinoma, she underwent complete surgical staging and adjuvant chemotherapy at this time. CONCLUSION A rare case of similar cancer in the ovary following treatment for PRMC was described. It is unclear whether the prognosis is improved by oophorectomy. Further cases and long-term follow-up are necessary.
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All-optical photoacoustic imaging system using fiber ultrasound probe and hollow optical fiber bundle. OPTICS EXPRESS 2013; 21:22023-33. [PMID: 24104094 DOI: 10.1364/oe.21.022023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
An all-optical 3D photoacoustic imaging probe that consists of an optical fiber probe for ultrasound detection and a bundle of hollow optical fibers for excitation of photoacoustic waves was developed. The fiber probe for ultrasound is based on a single-mode optical fiber with a thin polymer film attached to the output end surface that works as a Fabry Perot etalon. The input end of the hollow fiber bundle is aligned so that each fiber in the bundle is sequentially excited. A thin and flexible probe can be obtained because the probe system does not have a scanning mechanism at the distal end.
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Serum C-reactive protein reflects the proportions of cellular crescent formation and glomerulosclerosis in patients with microscopic polyangiitis. Presse Med 2013. [DOI: 10.1016/j.lpm.2013.02.195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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Distribution of abnormal prion protein in a sheep affected with L-type bovine spongiform encephalopathy. J Comp Pathol 2012; 149:113-8. [PMID: 23273583 DOI: 10.1016/j.jcpa.2012.11.231] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Revised: 09/10/2012] [Accepted: 11/07/2012] [Indexed: 11/27/2022]
Abstract
To investigate the topographical distribution and patterns of deposition of immunolabelled abnormal prion protein (PrP(Sc)), interspecies transmission of atypical L-type bovine spongiform encephalopathy (BSE) to Cheviot ewes (ARQ/ARQ genotype) was performed. L-type BSE was successfully transmitted via the intracerebral route to a ewe, with an incubation period of 1,562 days. Minimal vacuolar change was detected in the basal ganglia, thalamus and brainstem, and PrP(Sc) accumulated throughout the brain. The L-type BSE-affected sheep was characterized by conspicuous fine particulate deposits in the neuropil, particulate and/or granular intraneuronal and intraglial deposits, and the absence of PrP(Sc) plaques or stellate deposits. In addition, immunohistochemical and western blot analyses revealed that PrP(Sc) accumulation was present in peripheral nervous tissues (including the trigeminal ganglia and dorsal root ganglion) and adrenal glands, but was absent in lymphoid tissues. These results suggest that L-type BSE has distinct and distinguishable characteristics as well as PrP(Sc) tissue tropism in sheep.
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Remote Fourier transform-infrared spectral imaging system with hollow-optical fiber bundle. APPLIED OPTICS 2012; 51:6913-6916. [PMID: 23052066 DOI: 10.1364/ao.51.006913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Accepted: 08/28/2012] [Indexed: 06/01/2023]
Abstract
A spectral imaging system consisting of a Fourier transform-infrared spectrometer, a high-speed infrared camera, and a bundle of hollow-optical fibers transmitting infrared radiation images was constructed. Infrared transmission spectra were obtained by carefully processing multiple interferograms taken by high-speed photography. Infrared spectral images of a variety of samples captured by the system were measured. We successfully detected existence maps of the oil and fat of biological samples by mapping the transmission of specific wavelengths in the spectrum.
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Periodic Measurement of N-Telopeptides of Type I Collogen in Serum (SNTX) for Early Diagnosis of Bone Metastasis in Patients with Lung Cancer. Ann Oncol 2012. [DOI: 10.1016/s0923-7534(20)32494-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Prognostic significance of BAF57 expression in patients with endometrial carcinoma. Histol Histopathol 2012; 27:593-9. [PMID: 22419023 DOI: 10.14670/hh-27.593] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This study was conducted to elucidate the prognostic significance of BAF57 in patients with endometrial carcinoma. We investigated the relationship between the immunohistochemical expression of BAF57 and various clinicopathological variables in 111 endometrial carcinomas. Both univariate and multivariate regression analyses were performed. The correlations between the BAF57 expression and the other variables including estrogen receptor (ER) and p53 were examined. The high nuclear BAF57 expression was detected in 42 (37.8%) endometrial carcinomas, and 69 (62.2%) endometrial carcinomas were defined as having low nuclear BAF57 expression. The BAF57 expression was significantly associated with the surgical stage, grade of the tumor, myometrial invasion, lympho-vascular space invasion (LVSI) and lymph node metastasis. The 10-year overall survival rates of patients with low and high BAF57 expression were 96.9% and 58.2%, respectively (p<0.001). A multivariate analysis identified BAF57 expression as an independent prognostic factor. The BAF57 expression was significantly correlated with p53 expression (r=0.312, P=0.001), but was not correlated with ER expression (r= -0.141, P=0.14). The high BAF57 expression is an independent marker of poor prognosis of the patients in endometrial carcinomas. The inhibition of BAF57 activity may be one of the candidates for endometrial cancer therapy, especially therapy for aggressive tumors showing overexpression of p53.
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Non-linear analysis of stabilograms with alcoholic intake. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2012; 2012:4208-4211. [PMID: 23366856 DOI: 10.1109/embc.2012.6346895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Equilibrium function in the cerebellum (vestibulo-cerebellar system) can deteriorate under the influence of alcohol. In the Romberg posture, the center of gravity, which was measured every 50 ms by stabilometry, appeared to shift with alcohol ingestion. In the previous study, a locus in the center of gravity (stabilogram) was converted to values of statistical indices such as area of sway, total locus length, and locus length per unit area, although these indices could not always distinguish between the statokinesigrams sampled from seven healthy young males in sober and intoxicated states. This measurement was made with an AMTI force plate. In this study, "translation error" was estimated in a d-dimensional embedding space in order to compare statokinesigrams recorded before and after the ingestion of doubly diluted brandy in 30 s (1 ≤ d ≤ 10). We succeeded in validating a stochastic differential equation as a mathematical model of the body sway. The randomness in the model was preserved after alcohol intake and significantly increased in the medial/lateral direction. Visual information referred by the postural control system when standing might be interfered by the effects of intoxication, which was regarded as disturbance. This method is considered to be useful to diagnose the disorders of the vestibulocerebellar system.
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Abstract
The origin and transmission routes of atypical bovine spongiform encephalopathy (BSE) remain unclear. To assess whether the biological and biochemical characteristics of atypical L-type BSE detected in Japanese cattle (BSE/JP24) are conserved during serial passages within a single host, 3 calves were inoculated intracerebrally with a brain homogenate prepared from first-passaged BSE/JP24-affected cattle. Detailed immunohistochemical and neuropathologic analysis of the brains of second-passaged animals, which had developed the disease and survived for an average of 16 months after inoculation, revealed distribution of spongiform changes and disease-associated prion protein (PrP(Sc)) throughout the brain. Although immunolabeled PrP(Sc) obtained from brain tissue was characterized by the presence of PrP plaques and diffuse synaptic granular accumulations, no stellate-type deposits were detected. Western blot analysis suggested no obvious differences in PrP(Sc) molecular mass or glycoform pattern in the brains of first- and second-passaged cattle. These findings suggest failures to identify differences in mean incubation period and biochemical and neuropathologic properties of the BSE/JP24 prion between the first and second passages in cattle.
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Atomic alignment effect in the dissociative energy transfer reaction of metal carbonyls (Fe(CO)5, Ni(CO)4) with oriented Ar (3P2, M(J) = 2). J Phys Chem A 2011; 115:10888-93. [PMID: 21905731 DOI: 10.1021/jp206670w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The atomic alignment effect has been studied for the dissociative energy transfer reaction of metal carbonyls (Fe(CO)(5), Ni(CO)(4)) with the oriented Ar ((3)P(2), M(J) = 2). The emission intensity from the excited metal products (Fe*, Ni*) has been measured as a function of the atomic alignment in the collision frame. The selectivity of the atomic orbital alignment of Ar ((3)P(2), M(J) = 2) (rank 2 moment, a(2)) is found to be opposite for the two reaction systems; the Fe(CO)(5) reaction is favorable at the Π configuration (positive a(2)), while the Ni(CO)(4) reaction is favorable at the Σ configuration (negative a(2)). Moreover, a significant spin alignment effect (rank 4 moment, a(4)) is recognized only in the Ni(CO)(4) reaction. The atomic alignment effect turns out to be essentially different between the two reaction systems; the Fe(CO)(5) reaction is controlled by the configuration of the half-filled 3p atomic orbital of Ar ((3)P(2)) in the collision frame (L dependence), whereas the Ni(CO)(4) reaction is controlled by the configuration of the total angular moment J (including spin) of Ar ((3)P(2)) in the collision frame (J dependence). As the origin of J dependence observed only in the Ni(CO)(4) reaction, the correlation (and/or the interference) between two electron exchange processes via the electron rearrangements is proposed.
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Protein tectonics platform that facilitates synchrotron radiation life science. Acta Crystallogr A 2011. [DOI: 10.1107/s0108767311079347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Noninvasive subsurface analysis using multiple miniaturized Raman probes, part I: basic study of thin-layered transparent models of biomedical tissues. APPLIED SPECTROSCOPY 2011; 65:844-848. [PMID: 21819773 DOI: 10.1366/11-06245] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
This study describes a basic theory for reconstructing pure Raman signals of materials composing a multilayer sample from Raman spectra obtained using two types of miniaturized Raman probes. An illustrative example is demonstrated using a multilayer system of samples composed of the transparent plastics polymethylmethacrylate (PMMA) and polyethylene (PE) as a model of thin-layered biomedical tissues. When the same region of an object is measured using Raman probes with different focal properties, the Raman spectra provide different depth profile information depending on the level of light penetration. Thus, a detailed comparison of the spectra can provide an interesting opportunity to probe the differences between the layers. A simple analytic form is presented for reconstructing the pure Raman spectra of the embedded layer. The method applies an understanding of the Raman sampling volume in layered transparent materials to the interpretation of Raman spectra experimentally measured by multiple probes. The basic theory described here is necessary for the expansion of the technique to turbid media, such as biological samples, where light-scattering effects must be considered. The potential applications of the proposed method include material and catalyst subsurface probing through different embedded materials, such as assessment of silicon wafers, effective noninvasive screening for catalyst synthesis, and biomedical tissue research.
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