Biophotonics-Riga最新文献_第2页

Acetone measurements in the exhaled air by the cavity ring-down spectrometry 用空腔衰荡光谱法测定呼出空气中的丙酮

Biophotonics-Riga Pub Date : 2020-10-28 DOI: 10.1117/12.2581987

G. Revalde, K. Grundsteins, A. Abola

引用次数: 0

Application of acousto-optic tunable filters in the devices of skin cancer diagnostics 声光可调谐滤波器在皮肤癌诊断设备中的应用

Biophotonics-Riga Pub Date : 2020-10-28 DOI: 10.1117/12.2581750

K. Zaichenko, B. Gurevich

{"title":"Application of acousto-optic tunable filters in the devices of skin cancer diagnostics","authors":"K. Zaichenko, B. Gurevich","doi":"10.1117/12.2581750","DOIUrl":"https://doi.org/10.1117/12.2581750","url":null,"abstract":"Multispectral processing of images provides decreasing of information losses regarding spectral composition of an image. This method application produces the reflection spectrum of the observed object in each its point. It is especially efficient if an imaging acousto-optic tunable filter is used as a diffraction element of the processing system. We have proposed to use the multispectral processing of skin lesions images in order to find the possible signs of malignancies of patient’s skin. Multispectral processing method provides the visualization of the reflection patterns of the skin lesions, and the patterns at wavelengths which are inherent to the reflection from the malignancies, will show haw the certain kind of malignancy is spatially distributed inside the skin lesion to be studied. The preliminary investigations must be performed in order to determine the specific light wavelengths which are characteristic reflection wavelengths for different kinds of malignancies. The selection of spatial areas where the malignancy is found and detecting the places not occupied by the malignancy is very useful for successful treatment. The functional circuit of the device providing the multispectral processing of skin lesions images, has been presented and discussed. Keywords: multispectral processing, malignancies, skin lesions, information productivity, acousto-optic tunable filter, fine wavelength tuning","PeriodicalId":283327,"journal":{"name":"Biophotonics-Riga","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133822072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

The assessment of gingivitis using remote photoplethysmography 牙龈炎的影像学评价

Biophotonics-Riga Pub Date : 2020-10-28 DOI: 10.1117/12.2581969

Z. Marcinkevics, K. Ilango, P. Balode, U. Rubins, A. Grabovskis

{"title":"The assessment of gingivitis using remote photoplethysmography","authors":"Z. Marcinkevics, K. Ilango, P. Balode, U. Rubins, A. Grabovskis","doi":"10.1117/12.2581969","DOIUrl":"https://doi.org/10.1117/12.2581969","url":null,"abstract":"Gum disease caused by bacterial infection, systemic conditions or neurogenic inflammation remains a prevalent and important concern of public health in both, developing and developed countries, potentially causing tooth loss if left untreated. Therefore, a simple, cost-effective, and contactless diagnostic tool is needed in dentistry. The present study aims to develop and investigate the feasibility of a motion artefact-free, miniature imaging photoplethysmography system which is dedicated for assessment of gingivitis in the dental office. The device comprised of a sub-miniature monochromatic camera equipped with miniature lens, 4-LED ring illuminator, cross polarizers and bandpass optical filter (CW=540nm, FWHM=25nm). The present pilot study comprised six subjects. The transitory neurogenic gingival inflammation has been induced by topical application of capsaicin containing chilli extract. The photoplethysmography signal was acquired from the same site before and after inflammation, and perfusion maps were computed. During the procedure, the developed imaging system demonstrated motion artefact-free data recordings and high signal to noise ratio. As expected, topical application of chilli extract produced noticeable transitory neurogenic inflammation, detected in perfusion maps. The present findings confirm the potential of imaging photoplethysmography for gingival tissue inflammation assessment, and in the future could be utilized in the dental office.","PeriodicalId":283327,"journal":{"name":"Biophotonics-Riga","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132859033","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Assessment of Candida albicans biofilm growth by laser speckle contrast imaging 激光散斑对比成像评价白色念珠菌生物膜生长

Biophotonics-Riga Pub Date : 2020-10-28 DOI: 10.1117/12.2582216

M. Tamošiūnas, Simona Vaitkienė, Neringa Mikštaitė, Deimantė Galalytė, Neringa Kuliešienė, B. Cugmas, A. Lihachev, R. Daugelavičius

引用次数: 1

Spectral imaging as a tool for the evaluation of skin cancer post-operative scars 光谱成像作为评估皮肤癌术后疤痕的工具

Biophotonics-Riga Pub Date : 2020-10-28 DOI: 10.1117/12.2575704

M. Lange, S. Bozsányi, E. V. Plorina, A. Lihachev, A. Derjabo

引用次数: 3

Choice of photodetector characteristics for acousto-optic devices for bioelectric signals processing 生物电信号处理声光器件光电探测器特性的选择

Biophotonics-Riga Pub Date : 2020-10-28 DOI: 10.1117/12.2581737

K. Zaichenko, B. Gurevich

{"title":"Choice of photodetector characteristics for acousto-optic devices for bioelectric signals processing","authors":"K. Zaichenko, B. Gurevich","doi":"10.1117/12.2581737","DOIUrl":"https://doi.org/10.1117/12.2581737","url":null,"abstract":"It has been established recently that acousto-optic devices based on Bragg cells can be used for the bioelectric signals spectral processing. This processing can be realized only if acousto-optic spectrum analyzers with time or time-andspace integration are used. The frequency range of the processing system is defined by the complex of the acousto-optic Bragg cell and multielement photodetector characteristics. Two possible principles of the photodetector characteristics have been considered – direct and reverse principles. It has been shown that two parameters of photodetector play especially important part for the signal processing by means of acousto-optic device: charge accumulation time which defines the lower boundary of analyzed frequency range, and number of pixels per one resolvable interval which defines the upper boundary. The performed analysis has shown that the requirements for the second parameter are strongly defined by the investigated signal dynamic range, any distortion of which can produce the loss of important diagnostic information. It also has been shown that the correct choice of photodetector characteristics provides the acousto-optic processing system applicability for bot electrocardiographic and electroencephalographic signals obtained in the ultra high resolution mode.","PeriodicalId":283327,"journal":{"name":"Biophotonics-Riga","volume":"115 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115740706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Imaging photoplethysmography for evaluation of cutaneous sensory nerve fiber function 成像光体积脉搏图评价皮肤感觉神经纤维功能

Biophotonics-Riga Pub Date : 2020-10-28 DOI: 10.1117/12.2581705

Z. Marcinkevics, A. Aglinska, U. Rubins, A. Mikale, A. Grabovskis

{"title":"Imaging photoplethysmography for evaluation of cutaneous sensory nerve fiber function","authors":"Z. Marcinkevics, A. Aglinska, U. Rubins, A. Mikale, A. Grabovskis","doi":"10.1117/12.2581705","DOIUrl":"https://doi.org/10.1117/12.2581705","url":null,"abstract":"Peripheral neuropathy refers to peripheral nervous system dysfunction which affects up to 2% of the world's population. This condition is caused by damage to the small nerve fibers, hence its assessment is still challenging due to the lack of simple, non-invasive and objective diagnostic techniques. The present study aimed to develop and evaluate a simple, objective and non-invasive technique for assessment of small cutaneous sensory nerve fiber function. Our approach is based on utilization of imaging photoplethysmography and local skin heating. The effectiveness of the method was evaluated on young, healthy volunteers (n = 14) after 10 minutes of 45-degree local skin heating, while recording a photoplethysmographic signal simultaneously from the intact (control) and anesthetized skin (topical application of Emla gel) regions. In the anesthetized skin region, the local heating evoked flare area was 44% lower than that of intact skin. A similar trend was observed for the perfusion curve- perfusion peak in the anesthetized skin was substantially reduced in comparison to intact. The results indicate for the potential of the imaging photoplethysmography in the assessment of the small nerve fiber function. It is believed that this technique could be utilized in the clinics in the future to examine neuropathy patients and diagnose neuropathy.","PeriodicalId":283327,"journal":{"name":"Biophotonics-Riga","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130794159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Multispectral fluorescence detection of pigmented cutaneous tumours 色素皮肤肿瘤的多光谱荧光检测

Biophotonics-Riga Pub Date : 2020-10-28 DOI: 10.1117/12.2581967

E. Borisova, Tsanislava Genova, V. Mircheva, P. Troyanova, I. Bratchenko, L. Bratchenko, Y. Khristoforova, V. Zakharov, I. Lihacova, A. Lihacovs, J. Spigulis

{"title":"Multispectral fluorescence detection of pigmented cutaneous tumours","authors":"E. Borisova, Tsanislava Genova, V. Mircheva, P. Troyanova, I. Bratchenko, L. Bratchenko, Y. Khristoforova, V. Zakharov, I. Lihacova, A. Lihacovs, J. Spigulis","doi":"10.1117/12.2581967","DOIUrl":"https://doi.org/10.1117/12.2581967","url":null,"abstract":"We investigated pigmented skin tumour lesions in vivo and ex vivo, including benign and dysplastic nevi, as well as malignant lesions, such as pigmented basal cell carcinoma (BCC) and malignant melanoma (MM) lesions, to obtain a complex view about the feasibility of different excitation sources solely and/or in combination to induce fluorescence signal useful for diagnosis of various low-fluorescent cutaneous neoplasia. A specialized multispectral analysis of the data obtained was applied by using excitation in broad spectral range, covering ultraviolet, visible and near-infrared spectral range, that contribute considerably to: (1) fundamental determination of tumour tissues’ spectral properties, and (2) to increase the accuracy in determining the type of cutaneous pathology. The chromophores, related to the formation of ultraviolet and visible (UV-VIS) fluorescence in human normal skin and its pigmented lesions are mainly amino acids – tryptophan, tyrosine; structural proteins and their cross-links – collagen, elastin, keratin; co-enzymes - NADH, flavins; vitamins and lipids. In the near-infrared (NIR) spectral region, skin fluorescence emission properties are related to the presence of melanin pigment, lipids and endogenous porphyrins, if any, as the highest impact on the resultant emission spectrum is due to the melanin compound.","PeriodicalId":283327,"journal":{"name":"Biophotonics-Riga","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122111350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Biophotonics research in Riga: recent projects and results 里加的生物光子学研究:最近的项目和结果

Biophotonics-Riga Pub Date : 2020-10-28 DOI: 10.1117/12.2581799

J. Spigulis, I. Kuzmina, I. Lihacova, V. Lukinsone, B. Cugmas, A. Grabovskis, E. Kviesis-Kipge, A. Lihachev

引用次数: 0

Estimation of the effect of radionuclide contamination on Vicia sativa L. induction of chlorophyll fluorescence parameters using "Floratest" optical biosensor 利用“Floratest”光学生物传感器估计放射性核素污染对油菜叶绿素荧光参数诱导的影响

Biophotonics-Riga Pub Date : 2017-12-07 DOI: 10.1117/12.2297563

Y. Ruban, V. Illienko, N. Nesterova, O. Pareniuk, K. Shavanova

{"title":"Estimation of the effect of radionuclide contamination on Vicia sativa L. induction of chlorophyll fluorescence parameters using \"Floratest\" optical biosensor","authors":"Y. Ruban, V. Illienko, N. Nesterova, O. Pareniuk, K. Shavanova","doi":"10.1117/12.2297563","DOIUrl":"https://doi.org/10.1117/12.2297563","url":null,"abstract":"The presented research was aimed to determine the parameters of chlorophyll fluorescence (IChH) curve induction for Vicia sativa L. that were grown on radionuclide contaminated soils by using \"Floratest\" fluorometer. Plants were inoculated with 5 species of bacteria that might potentially block radionuclide uptake (Agrobacterium radiobacter IМВВ-7246, Azotobacter chroococcum UКМВ-6082, A. chroococcum UКМВ-6003, Bacillus megaterium UКМВ-5724, Rhizobium leguminosarum bv. viceae) and grown in sod-podzolic, сhernozem and peat-bog soils, contaminated with 137Cs (4000±340 Bq/kg). As a result of research, it was determined that the most stressful factors for vetch plants are combination of soil radionuclide and presence of Bacillus megaterium UКМ В-5724, as the number of inactive chlorophyll increased. In addition, the vetch plants significantly increased fixed level of fluorescence (Fst) under the influence of radioactive contamination in presence of Bacillus megaterium UKM B-5724, indicating inhibition of photosynthetic reactions. Other bacteria showed radioprotective properties in almost all types of soil.","PeriodicalId":283327,"journal":{"name":"Biophotonics-Riga","volume":"10592 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129785841","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3