scholarly journals Terahertz spectroscopy and imaging for gastric cancer diagnosis

2020 ◽  
Author(s):  
Faustino Wahaia ◽  
Irmantas Kašalynas ◽  
Linas Minkevičius ◽  
Catia Carvalho Silva ◽  
Andrzej Urbanowicz ◽  
...  
Keyword(s):  
Time Domain ◽  
Terahertz Spectroscopy ◽  
Human Cancer ◽  
Terahertz Waves ◽  
Terahertz Time Domain Spectroscopy ◽  
Tissue Samples ◽  
Time Domain Spectroscopy ◽  
Affected Tissue ◽  
Gastrointestinal Tissue ◽  
Thz Absorption

Terahertz waves are sensitive to differences in biological tissue hydration, we present promising results regarding the feasibility of applying this with terahertz time-domain spectroscopy and imaging for early detection of cancer through the characterisation of human gastrointestinal tissue with cancer-affected regions. To do that, healthy (normal) and carcinoma-affected gastric tissue samples at different stages were measured using transmission terahertz time-domain spectroscopy in the frequency range of 0.15–2.00 THz. Absorption coefficients and refractive index spectra of both normal and carcinoma-affected tissue were extracted and analysed. The results confirm that the techniques may be powerful tools to perform qualitative, early diagnosis of human cancer.

scholarly journals Transformation and dehydration kinetics of methylene blue hydrates detected by terahertz time-domain spectroscopy

RSC Advances ◽  
2017 ◽  
Vol 7 (66) ◽  
pp. 41667-41674 ◽  
Author(s):  
Shihan Yan ◽  
Hua Zhang ◽  
Zhongbo Yang ◽  
Mingjie Tang ◽  
Mingkun Zhang ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Time Domain ◽  
Terahertz Spectroscopy ◽  
Dehydration Kinetics ◽  
Terahertz Time Domain Spectroscopy ◽  
Time Domain Spectroscopy ◽  
Thz Absorption ◽  
Kinetics Of ◽  
Absorption Features ◽  
Crystalline Hydrates

Three methylene blue crystalline hydrates were identified by terahertz spectroscopy according to their different THz absorption features.

Determination of pesticides in a flour substrate by chemometric methods using terahertz spectroscopy

2018 ◽  
Vol 10 (42) ◽  
pp. 5097-5104 ◽  
Author(s):  
Binghua Cao ◽  
Hui Li ◽  
Mengbao Fan ◽  
Wei Wang ◽  
Mengyun Wang
Keyword(s):  
Time Domain ◽  
Terahertz Spectroscopy ◽  
Chemometric Methods ◽  
Terahertz Time Domain Spectroscopy ◽  
Time Domain Spectroscopy

Terahertz time-domain spectroscopy combined with chemometrics is utilized to identify imidacloprid and carbendazim in a flour substrate.

Characteristic fingerprint spectrum of neurotransmitter norepinephrine with broadband terahertz time-domain spectroscopy

The Analyst ◽  
2019 ◽  
Vol 144 (8) ◽  
pp. 2504-2510 ◽  
Author(s):  
Zhongjie Zhu ◽  
Chao Cheng ◽  
Chao Chang ◽  
Guanhua Ren ◽  
Jianbing Zhang ◽  
...  
Keyword(s):  
Absorption Spectrum ◽  
Time Domain ◽  
Vibrational Modes ◽  
Terahertz Time Domain Spectroscopy ◽  
Time Domain Spectroscopy ◽  
Thz Absorption ◽  
Broadband Terahertz

A broadband THz absorption spectrum of NE corresponds to specific vibrational modes.

scholarly journals Mail Inspection Based on Terahertz Time-Domain Spectroscopy

2021 ◽  
Vol 11 (3) ◽  
pp. 950
Author(s):  
Daniel Molter ◽  
Daniel Hübsch ◽  
Thorsten Sprenger ◽  
Korbinian Hens ◽  
Konstantinos Nalpantidis ◽  
...  
Keyword(s):  
Data Analysis ◽  
Spectral Range ◽  
Time Domain ◽  
Spectral Investigation ◽  
Machine Design ◽  
Terahertz Waves ◽  
Terahertz Time Domain Spectroscopy ◽  
Time Domain Spectroscopy

One of the most prominent applications of terahertz time-domain spectroscopy is the spectral investigation of materials covered by visibly opaque objects. Therefore, terahertz waves are well suited to inspect the content of mail. We report on our work on mail inspection in this spectral range including machine design, optical layouts, data analysis, and implementations.

scholarly journals Terahertz Time-domain Spectroscopy as a Novel Tool for Crystallographic Analysis in Cellulose: Cellulose I to Cellulose Ii, Tracing the Structural Changes Under Chemical Treatment

2021 ◽  
Author(s):  
Han Wang ◽  
Hiroki Kataoka ◽  
Satoru Tsuchikawa ◽  
Tetsuya Inagaki
Keyword(s):  
Absorption Coefficient ◽  
Time Domain ◽  
Structural Changes ◽  
Crystalline Lattice ◽  
Thz Radiation ◽  
Cellulose Ii ◽  
Cellulose I ◽  
Terahertz Time Domain Spectroscopy ◽  
Time Domain Spectroscopy ◽  
Thz Absorption

Abstract Terahertz time-domain spectroscopy (THz-TDS) has expanded possibilities in cellulose crystallography research, as THz radiation detects most intermolecular vibrations and responds to the phonons of crystalline lattices. In this study, we traced the transformation of the cellulose crystalline lattice from cellulose I to cellulose II by THz-TDS and X-ray powder diffraction. Cellulose II was obtained by treating cellulose I with NaOH of different concentrations (0 wt%–20 wt%, at 2 wt% intervals). The THz absorption coefficient spectra of cellulose II showed three characteristic peaks (at 1.32 THz, 1.76 THz, and 2.77 THz). The THz absorption coefficient spectra of cellulose II treated with 20-wt% NaOH and cellulose I without NaOH treatment were fitted by a seventh-order Fourier series. Thus, the THz absorption coefficient spectra of samples treated with NaOH of other concentrations could be considered a combination of these two fitted profiles of cellulose I and cellulose II, multiplied by different coefficients. Furthermore, the coefficients could reflect the relative contents of cellulose I and cellulose II in the samples.

scholarly journals Study of 2,4-D Spectral Characteristics and Its Detection in Zizania Latifolia Using Terahertz Time-Domain Spectroscopy

2019 ◽  
Vol 9 (11) ◽  
pp. 2248
Author(s):  
Pengcheng Nie ◽  
Chengyong Cai ◽  
Fangfang Qu ◽  
Lei Lin ◽  
Tao Dong ◽  
...  
Keyword(s):  
Time Domain ◽  
Density Functional ◽  
Terahertz Spectroscopy ◽  
Spectral Characteristics ◽  
Geometry Optimization ◽  
Main Peak ◽  
Terahertz Time Domain Spectroscopy ◽  
Zizania Latifolia ◽  
Time Domain Spectroscopy ◽  
2,4 Dichlorophenoxyacetic Acid

2,4-Dichlorophenoxyacetic acid (2,4-D) is a common plant growth regulator, which can remain in food and, with long-term consumption, threaten human health. Therefore, it is necessary to propose an effective detection method. Terahertz time-domain spectroscopy technique (THz-TDS) has good advantages in the quantitative and qualitative analysis of most biomolecules due to its rich fingerprint characteristics. In this paper, density functional theory (DFT) was applied to geometry optimization and frequency vibration calculation of 2,4-D, and THz-TDS was used to quantitatively detect 2,4-D in Zizania latifolia. The results showed that there were three characteristic absorption peaks of 2,4-D at 1.36, 1.60, and 2.38 THz, respectively, and the theoretical spectra were in good consistency with experimental spectra, with slight discrepancies. Additionally, the absorption peak at 1.36 THz had the best absorption characteristics and was chosen as the main peak for 2,4-D quantitative analysis. It was demonstrated that the limits of detection (LOD) of 2,4-D in Zizania latifolia were found to be as low as 5%, the absorbance intensity at 1.36 THz showed a good linear relationship (R2 = 0.9854) with 2,4-D concentration from 5% to 30%, and the recovery was 93.29%–98.75%. Overall, this work enriched the fingerprint database of pesticide molecules on the basis of terahertz spectroscopy and could provide a technical support for the detection of 2,4-D in food by terahertz spectroscopy.

Grating-assisted coupling of terahertz waves into a dielectric waveguide studied by terahertz time-domain spectroscopy

2002 ◽  
Vol 41 (30) ◽  
pp. 6507 ◽  
Author(s):  
Jean-François Roux ◽  
Fabien Aquistapace ◽  
Frédéric Garet ◽  
Lionel Duvillaret ◽  
Jean-Louis Coutaz
Keyword(s):  
Time Domain ◽  
Dielectric Waveguide ◽  
Terahertz Waves ◽  
Terahertz Time Domain Spectroscopy ◽  
Time Domain Spectroscopy

scholarly journals Quantification of triglyceride levels in fresh human blood by terahertz time-domain spectroscopy

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Dan Wang ◽  
Yu Zhang ◽  
Juan Han ◽  
Xiao Li ◽  
Xiaofeng Chen ◽  
...  
Keyword(s):  
Human Blood ◽  
Time Domain ◽  
Ex Vivo ◽  
Pearson Correlation ◽  
Terahertz Time Domain Spectroscopy ◽  
Absorption Coefficients ◽  
Time Domain Spectroscopy ◽  
Pilot Clinical Study ◽  
Biochemical Analyzer ◽  
Thz Absorption

AbstractWe conducted a pilot clinical study to investigate ex vivo fresh human blood from 93 patients with coronary heart disease (CHD). The results indicated that terahertz (THz) time-domain spectroscopy (TDS) can be used to quantify triglyceride (TG) levels in human blood. Based on the TG concentrations and corresponding THz absorption coefficients, the Pearson correlation analysis demonstrated that the THz absorption coefficients have a significant negative linear correlation with TG concentration. Comparisons between the THz measurements at 0.2 THz and an automatic biochemical analyzer were performed using an additional 20 blood samples, and the results confirmed that the relative error was less than 15%. Our ex vivo human blood study indicates that the THz technique can be used to assess blood TG levels in clinical diagnostic practice.

Wavelength Selection Method Based on Differential Evolution for Precise Quantitative Analysis Using Terahertz Time-Domain Spectroscopy

2017 ◽  
Vol 71 (12) ◽  
pp. 2653-2660 ◽  
Author(s):  
Zhi Li ◽  
Weidong Chen ◽  
Feiyu Lian ◽  
Hongyi Ge ◽  
Aihong Guan
Keyword(s):  
Quantitative Analysis ◽  
Differential Evolution ◽  
Time Domain ◽  
Selection Method ◽  
Wavelength Selection ◽  
Terahertz Time Domain Spectroscopy ◽  
Noise Sources ◽  
Time Domain Spectroscopy ◽  
Amino Acid Mixtures ◽  
Thz Absorption

Quantitative analysis of component mixtures is an important application of terahertz time-domain spectroscopy (THz-TDS) and has attracted broad interest in recent research. Although the accuracy of quantitative analysis using THz-TDS is affected by a host of factors, wavelength selection from the sample’s THz absorption spectrum is the most crucial component. The raw spectrum consists of signals from the sample and scattering and other random disturbances that can critically influence the quantitative accuracy. For precise quantitative analysis using THz-TDS, the signal from the sample needs to be retained while the scattering and other noise sources are eliminated. In this paper, a novel wavelength selection method based on differential evolution (DE) is investigated. By performing quantitative experiments on a series of binary amino acid mixtures using THz-TDS, we demonstrate the efficacy of the DE-based wavelength selection method, which yields an error rate below 5%.

Sign in / Sign up

Export Citation Format

Share Document