scholarly journals A Micron-Sized Laser Photothermal Effect Evaluation System and Method

Sensors ◽  
2021 ◽  
Vol 21 (15) ◽  
pp. 5133
Author(s):  
Jingjing Xu ◽  
Ming Zeng ◽  
Xin Xu ◽  
Junhui Liu ◽  
Xinyu Huo ◽  
...  
Keyword(s):  
Thermal Effect ◽  
Evaluation System ◽  
Reference Data ◽  
Measuring System ◽  
Photothermal Effect ◽  
Medical Laser ◽  
Laser Applications ◽  
Temperature Changes ◽  
Multi Wavelength ◽  
Basic Reference

The photothermal effects of lasers have played an important role in both medical laser applications and the development of cochlear implants with optical stimulation. However, there are few methods to evaluate the thermal effect of micron-sized laser spots interacting with other tissues. Here, we present a multi-wavelength micro-scale laser thermal effect measuring system that has high temporal, spatial and temperature resolutions, and can quantitatively realize evaluations in real time. In this system, with accurate 3D positioning and flexible pulsed laser parameter adjustments, groups of temperature changes are systematically measured when the micron-sized laser spots from six kinds of wavelengths individually irradiate the Pd/Cr thermocouple junction area, and reference data of laser spot thermal effects are obtained. This work develops a stable, reliable and universal tool for quantitatively exploring the thermal effect of micron-sized lasers, and provides basic reference data for research on light-stimulated neuron excitement in the future.

Contributing factors to fires in clinical settings during medical laser applications

2012 ◽  
Vol 24 (3) ◽  
pp. 032005 ◽  
Author(s):  
J. Pierce ◽  
S. Lacey ◽  
R. Lopez ◽  
J. Lippert ◽  
J. Franke
Keyword(s):  
Clinical Settings ◽  
Contributing Factors ◽  
Medical Laser ◽  
Laser Applications

scholarly journals Unsupervised Parameterization for Optimal Segmentation of Agricultural Parcels from Satellite Images in Different Agricultural Landscapes

2020 ◽  
Vol 12 (18) ◽  
pp. 3096
Author(s):  
Gideon Okpoti Tetteh ◽  
Alexander Gocht ◽  
Marcel Schwieder ◽  
Stefan Erasmi ◽  
Christopher Conrad
Keyword(s):  
Evaluation System ◽  
Reference Data ◽  
Cost Effective ◽  
Agricultural Landscapes ◽  
Bayesian Optimization ◽  
Absolute Difference ◽  
Optimization Approach ◽  
Lower Saxony ◽  
Optimal Segmentation ◽  
Unsupervised Methods

Image segmentation is a cost-effective way to obtain information about the sizes and structural composition of agricultural parcels in an area. To accurately obtain such information, the parameters of the segmentation algorithm ought to be optimized using supervised or unsupervised methods. The difficulty in obtaining reference data makes unsupervised methods indispensable. In this study, we evaluated an existing unsupervised evaluation metric that minimizes a global score (GS), which is computed by summing up the intra-segment uniformity and inter-segment dissimilarity within a segmentation output. We modified this metric and proposed a new metric that uses absolute difference to compute the GS. We compared this proposed metric with the existing metric in two optimization approaches based on the Multiresolution Segmentation (MRS) algorithm to optimally delineate agricultural parcels from Sentinel-2 images in Lower Saxony, Germany. The first approach searches for optimal scale while keeping shape and compactness constant, while the second approach uses Bayesian optimization to optimize the three main parameters of the MRS algorithm. Based on a reference data of agricultural parcels, the optimal segmentation result of each optimization approach was evaluated by calculating the quality rate, over-segmentation, and under-segmentation. For both approaches, our proposed metric outperformed the existing metric in different agricultural landscapes. The proposed metric identified optimal segmentations that were less under-segmented compared to the existing metric. A comparison of the optimal segmentation results obtained in this study to existing benchmark results generated via supervised optimization showed that the unsupervised Bayesian optimization approach based on our proposed metric can potentially be used as an alternative to supervised optimization, particularly in geographic regions where reference data is unavailable or an automated evaluation system is sought.

Advantages of the 2.94-μm wavelength for medical laser applications

1986 ◽  
Author(s):  
Leon Esterowitz ◽  
C. A. Hoffman ◽  
D. C. Tran ◽  
K. Levin ◽  
M. Storm ◽  
...  
Keyword(s):  
Medical Laser ◽  
Laser Applications

scholarly journals Empirical estimation of marine phytoplankton assemblages in coastal and offshore areas using an in situ multi-wavelength excitation fluorometer

2021 ◽  
Author(s):  
Taketoshi Kodama ◽  
Yukiko Taniuchi ◽  
Hiromi Kasai ◽  
Tamaha Yamaguchi ◽  
Misato Nakae ◽  
...  
Keyword(s):  
Reference Data ◽  
Vertical Direction ◽  
Japan Sea ◽  
Marine Phytoplankton ◽  
Empirical Estimation ◽  
Phytoplankton Assemblages ◽  
Plant Pigment ◽  
Multi Wavelength ◽  
Linear Inverse Model

AbstractPhytoplankton assemblages are important for understanding the quality of primary production in marine ecosystems. Here, we describe development of a methodology for monitoring marine phytoplankton assemblages using an in situ multi-wavelength excitation fluorometer (MEX) and its application for seasonal observations in coastal and offshore areas around Japan. The MEX recorded the fluorescence excited with nine light-emitting diodes, temperature, and sensor depth. We prepared reference datasets comprising temperature, MEX fluorescence, and plant-pigment-based chemotaxonomy phytoplankton assemblages. Target MEX fluorescence was decomposed by reference MEX fluorescence using a linear inverse model for calculating coefficients after the reference data were limited by temperature, followed by reconstruction of plant-pigment-based chemotaxonomy of the target MEX fluorescence using the coefficients and the chemotaxonomy assemblages of the reference data. Sensitivity analysis indicated poor estimation of the proportion and/or chlorophyll a-based abundance of chlorophytes, haptophytes, prasinophytes, and prochlorophytes; however, limiting the estimations to five chemotaxonomic groups [diatoms, dinoflagellates, cryptophytes, cyanobacteria (cyanophytes and prochlorophytes), and other eukaryotes (chlorophytes, haptophytes, and prasinophytes)] resulted in positive correlations of both the proportion and abundances, suggesting that the five taxonomic abundances were well-estimated using the MEX. Additionally, MEX observations denoted spatial and seasonal variations of phytoplankton assemblages, with high contributions from other eukaryotes in every area and season, cyanobacteria highly during the summer in surface Kuroshio and Japan Sea waters, and diatoms in the Oyashio and Oyashio–Kuroshio transition areas and the Okhotsk Sea. Furthermore, ratios of water-column-integrated chlorophyll-based abundances to those on the surface at the chemotaxonomy group level were differed among the areas and groups. These findings suggested that phytoplankton-assemblage monitoring in the vertical direction is essential for evaluation of their current biomass, and that the MEX promotes the acquisition of these observations.

scholarly journals Three Inspiring Review Articles on Photobiomodulation: Update 2021

2021 ◽  
Vol 06 (02) ◽  
pp. 1-1
Author(s):  
Gerhard Litscher ◽  
Keyword(s):  
Impact Factor ◽  
International Society ◽  
Important Application ◽  
Self Organization ◽  
Medical Laser ◽  
Laser Applications ◽  
Current Review ◽  
Review Articles

Photobiomodulation (PBM) is an accurate term for an effective and important application of light in medicine (such as in photomedicine). Three review articles of authors from the International Society of Medical Laser Applications (ISLA-Transcontinental) on the topic of PBM with a total of 116 printed pages, published in one renowned journal of molecular sciences with an impact factor of 13.668, are presented in the current review. The main topics are PBM, probiotics, curcumin, and arthritis. PBM can modulate cellular dysfunctions, trigger self-organization phenomena, and alleviate different diseases.

Sign in / Sign up

Export Citation Format

Share Document