Effects of Temperature on Optical Absorbance Spectra of Oxy-, Carboxy-, and Deoxyhemoglobin

1992 ◽  
Vol 38 (7) ◽  
pp. 1360-1364 ◽  
Author(s):  
J M Steinke ◽  
A P Shepherd
Keyword(s):  
Linear Function ◽  
Major Effect ◽  
Optical Absorbance ◽  
Absorbance Change ◽  
Temperature Controlled ◽  
Effects Of Temperature ◽  
Absorbance Spectra

Abstract The optical absorbance spectra of oxy-, carboxy-, and deoxyhemoglobin were recorded at wavelengths from 479 to 651 nm and at temperatures of 20, 30, and 40 degrees C. As noted in earlier reports, a major effect of lowering the temperature was an increase in the absorptivities at or near the absorbance maxima. However, at other wavelengths, reducing the temperature increased, decreased, or caused no change in absorbance. At wavelengths where temperature-induced shifts did occur, the absorbance change appeared to be a linear function of temperature. Unlike previous reports, the data presented here are quantitative and thus can be used to predict temperature-induced errors in spectrophotometric measurements of the relative concentrations of these hemoglobin species. Examples are given of the error that would occur in a widely used CO-Oximeter, the IL482, if it were not temperature controlled. Thus, the data presented here should be particularly useful to the operators and designers of spectrophotometric instruments such as oximeters, CO-Oximeters, and hemoglobinometers.

Humic Acid Functionalized - Silver Nanoparticles as Nanosensor for Colorimetric Detection of Copper (II) Ions in Aqueous Solutions

2020 ◽  
Vol 831 ◽  
pp. 142-150
Author(s):  
Edgar Clyde R. Lopez ◽  
Michael Angelo Zafra ◽  
Jon Nyner L. Gavan ◽  
Emil David A. Villena ◽  
Francis Eric P. Almaquer ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Humic Acid ◽  
Aqueous Solutions ◽  
Limit Of Detection ◽  
Colorimetric Detection ◽  
Hydrodynamic Diameter ◽  
Limit Of Quantification ◽  
Local Surface Plasmon Resonance ◽  
Optical Absorbance ◽  
Absorbance Spectra

Humic acid - functionalized silver nanoparticles (HA-AgNPs) were successfully synthesized and used to detect Cu (II) ions in aqueous solutions. The HA-AgNPs was shown to have an average hydrodynamic diameter of 101.4 nm and a polydispersity index of 0.447. The absorbance spectra of HA-AgNPs showed the characteristic local surface plasmon resonance (LSPR) peak of AgNPs at 408.3 nm. Addition of Cu (II) in the HA-AgNPs led to their agglomeration as evidenced by the change in their surface morphology and their corresponding optical absorbance spectra. The synthesized HA-AgNPs showed a strong linear response for Cu (II) concentrations in the range of 0.00 – 1.25 mM with a limit of detection (LoD) of 4.4428 ± 0.1091 mg L-1, a limit of quantification (LoQ) of 14.8094 ± 0.3636 mg L-1, and a limit of blank (LoB) of 0.1214 ± 0.0065 mg L-1. Statistical analysis showed that this calibration curve could be used to quantify Cu (II) concentrations within a 95% confidence level. Furthermore, HA-AgNPs was found to be selective for Cu (II) detection based on the selectivity study against common metal ions found in drinking water. This shows that the synthesized HA-AgNPs can be used as an environment-friendly colorimetric nanosensor for rapid and point-of-need quantification of Cu (II) ions in aqueous media.

scholarly journals Optical absorbance of the tympanic membrane in rat and human samples

PLoS ONE ◽  
2021 ◽  
Vol 16 (7) ◽  
pp. e0254902
Author(s):  
Madeleine Goblet ◽  
Farnaz Matin ◽  
Thomas Lenarz ◽  
Gerrit Paasche
Keyword(s):  
Tympanic Membrane ◽  
Biofilm Formation ◽  
Ex Vivo ◽  
Antibacterial Properties ◽  
Light Illumination ◽  
Chronic Infections ◽  
Adult Rats ◽  
Optical Absorbance ◽  
Human Samples ◽  
Absorbance Spectra

Chronic infections are often connected to biofilm formation. In presence of implants, this can lead to loss of the implant. Systemic or local application of drugs is relatively ineffective in case of biofilm formation. One technique to provide antibacterial properties on demand is the antibacterial photodynamic therapy (aPDT). Using this technique, these properties can be “switched on” by light illumination. In the middle ear with the semitransparent tympanic membrane, it might be possible in future to activate the antibacterial effect without opening the membrane. Therefore, we investigated the optical absorbance spectra of the tympanic membrane. Optical absorbance spectra were measured in ex vivo preparations from neonatal and adult rats with the membrane still being attached to the surrounding bony ring and four human samples. After performing area scans, the spot with the lowest absorbance being surrounded by a ring like structure with higher absorbance was chosen as region of interest for scanning wavelengths between 300 and 900 nm. Absorbance is generally higher at lower wavelengths with a local absorbance maximum at 420 nm and a weak second maximum with two neighbouring peaks at 540 / 580 nm and is significantly higher in adult rats compared to neonatal rats where about 10% of light was transmitted. The human samples show similar characteristics with a little higher absorbance. For activation of aPDT through the tympanic membrane, larger wavelengths are more promising. Whether the amount of light transmitted through the membrane would be sufficient to induce aPDT remains to be tested in further experiments.

Assessing the effects of temperature on the population of Aedes aegypti, the vector of dengue

2009 ◽  
Vol 137 (8) ◽  
pp. 1188-1202 ◽  
Author(s):  
H. M. YANG ◽  
M. L. G. MACORIS ◽  
K. C. GALVANI ◽  
M. T. M. ANDRIGHETTI ◽  
D. M. V. WANDERLEY
Keyword(s):  
Life Cycle ◽  
Aedes Aegypti ◽  
Controlled Experiments ◽  
Dengue Disease ◽  
Offspring Number ◽  
Vector Population ◽  
Different Temperatures ◽  
Vector Borne ◽  
Temperature Controlled ◽  
Effects Of Temperature

SUMMARYDengue is a vector-borne disease transmitted by the mosquito Aedes aegypti. The incidence of dengue disease shows a clear dependence on seasonal variation. How does the temperature affect the incidence? We addressed this question indirectly by estimating the size of the A. aegypti population for different temperatures applying population dynamics theory. In order to achieve this objective we designed temperature-controlled experiments to assess the entomological parameters regarding the mosquito's life-cycle at different temperatures. By obtaining the mortality, transition and oviposition rates for different stages of the life-cycle of the mosquito we were able to calculate the basic offspring number Q0, which is the capacity of vector reproduction and ultimately gives the size of the vector population.

The Interaction of Plasticizers and Polymers

1945 ◽  
Vol 18 (4) ◽  
pp. 790-802
Author(s):  
Elizabeth M. Frith
Keyword(s):  
Linear Function ◽  
General Problem ◽  
Mixed Solvent ◽  
Polymer Solutions ◽  
Mixed Solvents ◽  
Previous Theory ◽  
Effect Of Solvent ◽  
Dilute Polymer Solutions ◽  
Effects Of Temperature ◽  
Comparative Measure

Abstract The general problem of plasticizer compatibility is discussed, and it is suggested that a comparative measure of compatibility can be obtained from experiments which measure polymer-plasticizer interactions (w). Experiments are described which measure the viscosity of dilute polymer solutions in suitable mixed solvents containing the plasticizer in question. The slope of the ηsp/c−c curve is shown to be related to the equilibrium extent of swelling of the polymer in the pure plasticizer and, in general, the slope of the curve is a good comparative measure of the plasticizer's compatibility. The effects of temperature and composition of the mixed solvent are also discussed. The experiments are considered in the light of a previous theory of the effect of solvent on the ηsp/c ratio: the results do not support the suggested view that the slope of the ηsp/c−c curve is a simple linear function of w/kT.

The effects of temperature and photoperiod on diapause development in the eggs of four species of Lestes (Odonata: Zygoptera)

1973 ◽  
Vol 51 (12) ◽  
pp. 1257-1265 ◽  
Author(s):  
W. W. Sawchyn ◽  
N. S. Church
Keyword(s):  
Subsequent Development ◽  
Second Phase ◽  
Inhibitory Effects ◽  
Temperature Controlled ◽  
Effects Of Temperature ◽  
Diapause Development

Lestes disjunctus, L. unguiculatus, and L. dryas diapause late in embryogenese when the embryo is almost fully formed. Lestes congener enters diapause just before blastokinesis. Lestes disjunctus, L. unguiculatus, and L. congener undergo a primarily temperature-controlled phase of diapause development, which proceeds most rapidly at 10 °C. In the field it is completed in most eggs by the end of October in L. disjunctus and L. unguiculatus, and by the end of November in L. congener. Subsequent development in L. disjuncius and L. unguiculatus is inhibited by photoperiods shorter than 12 to 14 h. There apparently is some overlap between the temperature- and photoperiod-controlled phases. The inhibitory effects of short photoperiods gradually disappear during the winter. In L. congener there is no significant photoperiod-controlled second phase of diapause. Diapause development in L. dryas probably is similar to that in L. disjunctus and L. unguiculatus.

scholarly journals Hydrogen-Free Diamond Like Carbon Films with Embedded Cu Nanoparticles: Structure, Composition and Reverse Saturable Absorption Effect

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 760
Author(s):  
Meškinis ◽  
Vasiliauskas ◽  
Viskontas ◽  
Andrulevičius ◽  
Guobienė ◽  
...  
Keyword(s):  
Surface Plasmon Resonance ◽  
Surface Plasmon ◽  
Plasmon Resonance ◽  
Carbon Films ◽  
Saturable Absorption ◽  
Reverse Saturable Absorption ◽  
Diamond Like Carbon ◽  
Optical Absorbance ◽  
Wide Range ◽  
Absorbance Spectra

In the present research, hydrogen-free diamond like carbon films with embedded copper nanoparticles (DLC:Cu) were grown by simultaneous DC magnetron sputtering of the graphite and copper targets. X-ray photoelectron spectroscopy was used to define the composition of the samples. Atomic force microscopy studies of diamond, like carbon films containing different amount of copper, revealed wide range of the surface morphologies as well as sizes and shapes of the embedded copper nanoclusters. Raman scattering spectra of all the DLC:Cu films investigated were typical for diamond-like carbon (including samples containing more than 60 at.% of copper). sp3/sp2 carbon bond ratio in the films decreased with the increase of the Cu amount in the films. According to the optical absorbance measurements, the surface plasmon resonance related absorption peak of DLC:Cu films was only detected in the films containing 28.45 at.% Cu. For the diamond like carbon films containing more than 40 at.% Cu, a further increase of Cu amount in the nanocomposite resulted in minor changes of the absorbance spectra. Some correlation between the changes of the samples surface morphology as well as phase structure and optical absorbance spectra of the films was found. In all cases, reverse-saturable absorption of the DLC:Cu films was observed. For some DLC:Cu films damage of the sample occurred at higher light fluences that can be related to the heating that is caused by the surface plasmon resonance effect.

Photoinduced degradation of organic dye over LiBiO3 under illumination of white fluorescent light

2010 ◽  
Vol 25 (1) ◽  
pp. 177-181 ◽  
Author(s):  
Naoki Kikugawa ◽  
Liqun Yang ◽  
Takehiko Matsumoto ◽  
Jinhua Ye
Keyword(s):  
Methylene Blue ◽  
Dye Degradation ◽  
Molecular Form ◽  
Wavelength Dependence ◽  
Organic Dye ◽  
Fluorescent Light ◽  
Optical Absorbance ◽  
Wide Range ◽  
Photonic Efficiency ◽  
Absorbance Spectra

We report dye-degradation effects of a semiconductor LiBiO3 revealed under illumination of a conventionally used white fluorescent light. Optical absorbance spectra of LiBiO3 were broadened so smoothly, with the absorption edge penetrated to around 730 nm, that the material was able to absorb a wide range of visible light. Results showed that solution of a standard dye, methylene blue, was degraded completely after 4 h illumination. Furthermore, the value of total organic carbon decreased 70% in the decolorized solution, suggesting that the molecular form of the original methylene blue was mineralized effectively to nonorganic fragments by the photoinduced oxidization effect. Moreover, the wavelength dependence of apparent photonic efficiency was evaluated using a standard Xe lamp coupled with monochromatic filters. These results were interpreted from the viewpoint of this material’s electronic structure.

scholarly journals Extension of the broadband single-mode integrated optical waveguide technique to the ultraviolet spectral region and its applications

The Analyst ◽  
2014 ◽  
Vol 139 (6) ◽  
pp. 1396-1402 ◽  
Author(s):  
Rodrigo S. Wiederkehr ◽  
Sergio B. Mendes
Keyword(s):  
Optical Waveguide ◽  
Spectral Region ◽  
Single Mode ◽  
Optical Absorbance ◽  
Integrated Optical ◽  
Ultraviolet Spectral Region ◽  
Integrated Optical Waveguide ◽  
Absorbance Spectra

We report here the fabrication, characterization, and application of a single-mode integrated optical waveguide (IOW) spectrometer capable of acquiring optical absorbance spectra of surface-immobilized molecules in the visible and ultraviolet spectral region down to 315 nm.

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