scholarly journals Colour change on different body regions provides thermal and signalling advantages in bearded dragon lizards

2016 ◽  
Vol 283 (1832) ◽  
pp. 20160626 ◽  
Author(s):  
Kathleen R. Smith ◽  
Viviana Cadena ◽  
John A. Endler ◽  
Warren P. Porter ◽  
Michael R. Kearney ◽  
...  
Keyword(s):  
Near Infrared ◽  
Colour Change ◽  
Maximum Temperature ◽  
Skin Reflectance ◽  
Body Regions ◽  
Dependent Change ◽  
Bearded Dragon ◽  
Uv Visible ◽  
Thermoregulatory Function ◽  
Response To Temperature

Many terrestrial ectotherms are capable of rapid colour change, yet it is unclear how these animals accommodate the multiple functions of colour, particularly camouflage, communication and thermoregulation, especially when functions require very different colours. Thermal benefits of colour change depend on an animal's absorptance of solar energy in both UV–visible (300–700 nm) and near-infrared (NIR; 700–2600 nm) wavelengths, yet colour research has focused almost exclusively on the former. Here, we show that wild-caught bearded dragon lizards ( Pogona vitticeps ) exhibit substantial UV–visible and NIR skin reflectance change in response to temperature for dorsal but not ventral (throat and upper chest) body regions. By contrast, lizards showed the greatest temperature-independent colour change on the beard and upper chest during social interactions and as a result of circadian colour change. Biophysical simulations of heat transfer predicted that the maximum temperature-dependent change in dorsal reflectivity could reduce the time taken to reach active body temperature by an average of 22 min per active day, saving 85 h of basking time throughout the activity season. Our results confirm that colour change may serve a thermoregulatory function, and competing thermoregulation and signalling requirements may be met by partitioning colour change to different body regions in different circumstances.

scholarly journals Dermacozine N, the First Natural Linear Pentacyclic Oxazinophenazine with UV–Vis Absorption Maxima in the Near Infrared Region, Along with Dermacozines O and P Isolated from the Mariana Trench Sediment Strain Dermacoccus abyssi MT 1.1T

Marine Drugs ◽  
2021 ◽  
Vol 19 (6) ◽  
pp. 325
Author(s):  
Bertalan Juhasz ◽  
Dawrin Pech-Puch ◽  
Jioji N. Tabudravu ◽  
Bastien Cautain ◽  
Fernando Reyes ◽  
...  
Keyword(s):  
Linear Regression ◽  
Density Functional ◽  
Near Infrared ◽  
Linear Regression Analysis ◽  
2D Nmr ◽  
Multiple Linear Regression Analysis ◽  
Infrared Region ◽  
Cellular Level ◽  
Mariana Trench ◽  
Uv Visible

Three dermacozines, dermacozines N–P (1–3), were isolated from the piezotolerant Actinomycete strain Dermacoccus abyssi MT 1.1T, which was isolated from a Mariana Trench sediment in 2006. Herein, we report the elucidation of their structures using a combination of 1D/2D NMR, LC-HRESI-MSn, UV–Visible, and IR spectroscopy. Further confirmation of the structures was achieved through the analysis of data from density functional theory (DFT)–UV–Visible spectral calculations and statistical analysis such as two tailed t-test, linear regression-, and multiple linear regression analysis applied to either solely experimental or to experimental and calculated 13C-NMR chemical shift data. Dermacozine N (1) bears a novel linear pentacyclic phenoxazine framework that has never been reported as a natural product. Dermacozine O (2) is a constitutional isomer of the known dermacozine F while dermacozine P (3) is 8-benzoyl-6-carbamoylphenazine-1-carboxylic acid. Dermacozine N (1) is unique among phenoxazines due to its near infrared (NIR) absorption maxima, which would make this compound an excellent candidate for research in biosensing chemistry, photodynamic therapy (PDT), opto-electronic applications, and metabolic mapping at the cellular level. Furthermore, dermacozine N (1) possesses weak cytotoxic activity against melanoma (A2058) and hepatocellular carcinoma cells (HepG2) with IC50 values of 51 and 38 μM, respectively.

Synthesis of Amino-Functionalized Graphene Oxide/Azobenzene Polyimide and its Simulation of Optical Switches

2017 ◽  
Vol 231 (11-12) ◽  
Author(s):  
Tianlin Cao ◽  
Fanyu Zhao ◽  
Zulin Da ◽  
Fengxian Qiu ◽  
Dongya Yang ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Near Infrared ◽  
Optical Switches ◽  
Attenuated Total Reflection ◽  
Functionalized Graphene ◽  
Visible Spectroscopy ◽  
Scanning Calorimetry ◽  
Functionalized Graphene Oxide ◽  
Uv Visible ◽  
532 Nm

AbstractIn this work, an amino-functionalized graphene oxide (AFGO) was synthesized by graphene oxide (GO) and ethylene diamine. A novel amino-functionalized graphene oxide/azobenzene polyimide (AFGO/ACPI) was synthesized with AFGO, azobenzene chromophore and pyromellitic dianhydride (PMDA). The structure, mechanical and thermal property of AFGO/ACPI were characterized and measured by fourier transform infrared, UV-visible spectroscopy, near-infrared spectrum, thermogravimetric analysis and differential scanning calorimetry. To obtain the refractive index of AFGO/ACPI at different temperature and wavelength (532 nm, 650 nm and 850 nm), the attenuated total reflection (ATR) method was used to measure, and thermo optic coefficients (dn/dT) were −7.22×10

Hyperspectral Cathodoluminescence Imaging and Analysis Extending from Ultraviolet to Near Infrared

2012 ◽  
Vol 18 (6) ◽  
pp. 1239-1245 ◽  
Author(s):  
C.M. MacRae ◽  
N.C. Wilson ◽  
A. Torpy ◽  
C.J. Davidson
Keyword(s):  
Rare Earth ◽  
Near Infrared ◽  
Preliminary Investigation ◽  
X Rays ◽  
Spectral Mapping ◽  
X Ray ◽  
Quantitative Electron Probe Microanalysis ◽  
Uv Visible ◽  
Intense Emission ◽  
Cathodoluminescence Imaging

AbstractThe measurement of near-infrared (NIR) cathodoluminescence (CL) with sufficient sensitivity to allow full spectral mapping has been investigated through the application of optimized grating spectrometers that allow the ultraviolet (UV), visible, and NIR CL spectra to be measured simultaneously. Two optical spectrometers have been integrated into an electron microprobe, allowing simultaneous collection of hyperspectral CL (UV-NIR), characteristic X-rays, and electron signals. Combined hyperspectral CL spectra collected from two natural apatite (Ca5[PO4]3[OH,F]) samples from Wilberforce (Ontario, Canada) and Durango (Mexico) were qualitatively analyzed to identify the emission centers and then deconvoluted pixel-by-pixel using least-squares fitting to produce a series of ion-resolved CL intensity maps. Preliminary investigation of apatite has shown strong NIR emissions associated primarily with the rare-earth element Nd. Details of growth and alteration were revealed in the NIR that were not discernable with electron-induced X-ray mapping. Intense emission centers from Nd3+ and Sm3+ were observed in the spectra from both apatites, along with minor emissions from other 3+ rare-earth elements. Quantitative electron probe microanalysis was performed on points within the mapped area of the Durango apatite to produce a calibration line relating cathodoluminescent intensity of the fitted peak centered at 1,073 nm (1.156 eV) to the Nd concentration.

scholarly journals In Situ Ultraviolet Polymerization Using Upconversion Nanoparticles: Nanocomposite Structures Patterned by Near Infrared Light

Nanomaterials ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 2054
Author(s):  
Hongsub Jee ◽  
Guanying Chen ◽  
Paras N. Prasad ◽  
Tymish Y. Ohulchanskyy ◽  
Jaehyeong Lee
Keyword(s):  
Polymer Nanocomposites ◽  
Near Infrared ◽  
Infrared Light ◽  
Upconversion Nanoparticles ◽  
Nanocomposite Structure ◽  
Shell Design ◽  
Uv Visible ◽  
Harsh Conditions ◽  
Nanocomposite Structures

In this paper, we report an approach to polymerization of a nanocomposite containing UV-polymerizable organic material and inorganic, NaYbF4:Tm3+ core-based nanoparticles (NPs), which are optimized for upconversion of near infrared (NIR) to ultraviolet (UV) and blue light. Our approach is compatible with numerous existing UV-polymerizable compositions and the NaYF4: Yb, Tm3+ core-based NPs are much more stable against harsh conditions than NIR organic photo-initiators proposed earlier. The use of a core-shell design for the NPs can provide a suitable method for binding with organic constituents of the nanocomposite, while maintaining efficient NIR-to-UV/blue conversion in the NaYbF4 core. The prepared photopolymerized transparent polymer nanocomposites display upconversion photoluminescence in UV, visible and NIR ranges. We also demonstrate a successful fabrication of polymerized nanocomposite structure with millimeter/submillimeter size uniformly patterned by 980 nm irradiation of inexpensive laser diode through a photomask.

Efficient conversion of broad UV–visible light to near-infrared emission in Mn4+/Yb3+ co-doped CaGdAlO4 phosphors

2019 ◽  
Vol 210 ◽  
pp. 189-201 ◽  
Author(s):  
Jianxu Hu ◽  
Yuanpeng Zhang ◽  
Bin Lu ◽  
Haiping Xia ◽  
Huanqing Ye ◽  
...  
Keyword(s):  
Visible Light ◽  
Near Infrared ◽  
Infrared Emission ◽  
Efficient Conversion ◽  
Uv Visible ◽  
Near Infrared Emission ◽  
Co Doped

scholarly journals Context-dependent effects of relative temperature extremes on bill morphology in a songbird

2020 ◽  
Vol 7 (4) ◽  
pp. 192203
Author(s):  
Katie LaBarbera ◽  
Kyle J. Marsh ◽  
Kia R. R. Hayes ◽  
Talisin T. Hammond
Keyword(s):  
Extreme Environments ◽  
Negative Relationship ◽  
Environmental Context ◽  
Maximum Temperature ◽  
Relative Temperature ◽  
Generalist Species ◽  
Environmental Extremes ◽  
Bill Morphology ◽  
Thermoregulatory Function ◽  
Cool Climate

Species increasingly face environmental extremes. Morphological responses to changes in average environmental conditions are well documented, but responses to environmental extremes remain poorly understood. We used museum specimens to investigate relationships between a thermoregulatory morphological trait, bird bill surface area (SA) and a measure of short-term relative temperature extremity (RTE), which quantifies the degree that temperature maxima or minima diverge from the 5-year norm. Using a widespread, generalist species, Junco hyemalis , we found that SA exhibited different patterns of association with RTE depending on the overall temperature regime and on precipitation. While thermoregulatory function predicts larger SA at higher RTE, we found this only when the RTE existed in an environmental context that opposed it: atypically cold minimum temperature in a warm climate, or atypically warm maximum temperature in a cool climate. When environmental context amplified the RTE, we found a negative relationship between SA and RTE. We also found that the strength of associations between SA and RTE increased with precipitation. Our results suggest that trait responses to environmental variation may qualitatively differ depending on the overall environmental context, and that environmental change that extremifies already-extreme environments may produce responses that cannot be predicted from observations in less-extreme contexts.

Design and preparation of UV-visible-shortwave near infrared cut-off and mid-infrared antireflection coating

Optik ◽  
2021 ◽  
Vol 227 ◽  
pp. 165470
Author(s):  
Meng Guo ◽  
Kui Yi ◽  
Xinqiang Cui ◽  
Shuying Shao ◽  
Guohang Hu ◽  
...  
Keyword(s):  
Near Infrared ◽  
Antireflection Coating ◽  
Mid Infrared ◽  
Uv Visible

A Bi2WO6-Based Hybrid Photocatalyst with Broad Spectrum Photocatalytic Properties under UV, Visible, and Near-Infrared Irradiation

2013 ◽  
Vol 25 (36) ◽  
pp. 5075-5080 ◽  
Author(s):  
Jian Tian ◽  
Yuanhua Sang ◽  
Guangwei Yu ◽  
Huaidong Jiang ◽  
Xiaoning Mu ◽  
...  
Keyword(s):  
Broad Spectrum ◽  
Near Infrared ◽  
Photocatalytic Properties ◽  
Infrared Irradiation ◽  
Uv Visible ◽  
Hybrid Photocatalyst
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