Spectral Color Research Articles

IMPORTANCE OF THE COLOR TEMPERATURE IN COLD WHITE LIGHT EMISSION OF Ca2MgSi2O7: Dy3+ PHOSPHOR

A promising candidate of white light-emitting (Ca2MgSi2O7: Dy3+) phosphor was successfully synthesized via traditional high-temperature solid-state synthesis technique using boric acid (H3BO3) as a fuel. The synthesized material sample was characterized with the help of powder X-ray diffraction (PXRD), FT-IR (Fourier Transform Infra-red) Spectroscopy, FESEM (Field Emission Scanning Electron Microscopy) and PL (Photoluminescence) spectra. Using the Debye-Scherer formula and UDM method, the crystallite size and crystal lattice strain were evaluated, respectively. Photoluminescence (PL) properties (both excitation & emission spectra) for the prepared phosphor were systematically investigated in detail. Photoluminescence spectra were revealed that the strong transition of spectral emission lines centered at 484nm (blue), 578nm (yellow) and weak transition of spectral emission lines centered at 615nm (red) wavelength. These peaks were assigned to following transitions (4F9/2 → 6H15/2,13/2,11/2), which are responsible for the (f→f) transitions from the ground level (lower energy state) to excited level (higher energy state) in the 4f9electronic configuration of dopant [Dy3+] ions. CIE color chromaticity coordinates and Color Correlated Temperature (CCT) of synthesized Ca2MgSi2O7: Dy3+ phosphor sample is well suited for the generation of cold white light emission with a CIE coordinate value of (X = 0.31, Y = 0.32) and CCT value also calculated as 5167K. Here upon, it is highly applicable to be a novel hopeful phosphor for cold WLEDs.

Effects of Manual Versus Instrumental Spinal Manipulation on Blood Flow of the Vertebral and Internal Carotid Arteries in Participants With Chronic Nonspecific Neck Pain: A Single-Blind, Randomized Study

ObjectiveThe aim of this study was to compare the hemodynamic effects of manual spinal manipulation (MSM) and instrumental spinal manipulation (ISM) on the vertebral artery (VA) and internal carotid artery (ICA) in participants with chronic nonspecific neck pain (NNP). MethodsThirty volunteers aged 20 to 40 years old with NNP over 3 months duration were included. Participants were randomly divided into the following 2 groups: (1) MSM group (n = 15) and (2) ISM group (n = 15). Ipsilateral (intervention side) and contralateral (opposite side of intervention) VAs and ICAs were evaluated using spectral color Doppler ultrasound before and immediately after manipulation. Measurements were recorded by visualizing the ICA carotid sinus (C4 level) and the VA at the V3 segment (C1-C2 level). The blood flow parameters of peak systolic velocity (PSV), end-diastolic velocity, resistive index, and volume flow (only for VA) were evaluated. The spinal segment, in which biomechanical aberrant movement was detected by palpation in the upper cervical spine, was manually manipulated in the MSM group. The same methodology was performed for the ISM group using an Activator V instrument (Activator Methods). ResultsIntragroup analysis exhibited no statistically significant difference between the MSM and ISM groups in terms of PSV, end-diastolic velocity, resistive index of ipsilateral and contralateral ICA and VA, in addition to volume flow of both VAs preintervention and postintervention (P > .05). Within the intergroup analysis, there was a significant difference in ipsilateral ICA PSV (P = .031) (preintervention vs postintervention difference was –7.9 ± 17.2 cm/s [95% confidence interval, –17.4 to 1.6] in the ISM group and 8.7 ± 22.5 cm/s [95% confidence interval, –3.6 to 21.2]) in the MSM group (P < .05). Other parameters did not show any significant difference (P > .05). ConclusionManual and instrumental spinal manipulations applied to the upper cervical spine in participants with chronic NNP did not appear to alter blood flow parameters of the VAs and ICAs.

All-Solution Processed Single-Layer WOLEDs Using [Pt(salicylidenes)] as Guests in a PFO Matrix.

Herein, we report the synthesis and characterization of two Pt(II) coordination compounds, the new platinum(II)[N,N′-bis(salicylidene)-3,4-diaminobenzophenone)] ([Pt(sal-3,4-ben)]) and the already well-known platinum(II)[N,N′-bis(salicylidene)-o-phenylenediamine] ([Pt(salophen)]), along with their application as guests in a poly [9,9-dioctylfluorenyl-2,7-diyl] (PFO) conjugated polymer in all-solution processed single-layer white organic light-emitting diodes. Completely different performances were achieved: 2.2% and 15.3% of external quantum efficiencies; 2.8 cd A−1 and 12.1 cd A−1 of current efficiencies; and 3103 cd m−2 and 6224 cd m−2 of luminance for the [Pt(salophen)] and [Pt(sal-3,4-ben)] complexes, respectively. The Commission Internationale de l’Eclairage (CIE 1931) chromaticity color coordinates are (0.33, 0.33) for both 0.1% mol/mol Pt(II):PFO composites at between approximately 3.2 and 8 V. The optoelectronic properties of doped and neat PFO films have been investigated, using steady-state and time-resolved photoluminescence. Theoretical calculations at the level of relativistic density functional theory explained these results, based on the presence of the Pt(II) central ion’s phosphorescence emission, considering spin-orbit coupling relationships. The overall results are explained, taking into account the active layer morphological properties, along with the device’s electric balance and the emitter’s efficiencies, according to deep-trap space-charge models. Considering the very simple structure of the device and the ease of synthesis of such compounds, the developed framework can offer a good trade-off for solution-deposited white organic light-emitting diodes (WOLEDs), with further applications in the field of lighting and signage.

Fluorescent phenothiazine-triazine donor-acceptor conjugates by facile consecutive nucleophilic displacement – Color tuning by substitution and protochromicity

A series of phenothiazine-triazine chromophores is prepared starting from brominated phenothiazine in a one-pot fashion by twofold nucleophilic substitution on cyanuric chloride. The title compounds show high fluorescence quantum yields in solution and in the solid state spanning a color range from deep blue to red by modulating the acceptor strength of the triazine moiety. Electron deficient substituted triazine chromophores exhibit a strong charge transfer character as shown by solvatochromism studies and small singlet-triplet energy gap making them interesting-candidates for thermally activated delayed fluorescence (TADF). Protonation of an electron rich triazine chromophore resulted in shifted spectral emission and showed in one case the formation of complementary emission colors and white light formation. Thus, by substitution of the triazine spectral emission color can be fine-tuned and specific photophysical properties like TADF and white light emission can be addressed.

Magnifying Chromoendoscopy with Flexible Spectral Imaging Color Enhancement, Indigo Carmine, and Crystal Violet in Predicting the Histopathology of Colorectal Polyps: Diagnostic Value in a Scare-Setting Resource.

Background and Aims Virtual magnifying chromoendoscopy with flexible spectral imaging color enhancement (FICE), image-enhanced endoscopy techniques, and dye-staining magnifying chromoendoscopy (with Indigo carmine and Crystal violet) have contributed to better visualization of the pit pattern and vascular structure of colorectal polyp. Therefore, magnifying chromoendoscopy is capable of predicting the histopathological results of colorectal polyp without biopsy and remains their diagnostic values over time, especially in scare-setting resources. This study compared the images of magnifying chromoendoscopy between FICE, Indigo carmine, and Crystal violet and then assessed their diagnostic values based on colorectal polyps' histopathology as a gold standard. Methods A total of 332 polyps of 266 patients were endoscopically evaluated from June 2016 to September 2019. After identified by white light endoscopy, polyps continued to be evaluated by virtual magnifying chromoendoscopy (×50-150 times) with FICE. The capillary-vessel pattern was divided into 5 subtypes according to the number, morphology, and distribution of the fine blood vessels according to Teixeira classification. Next, they were stained with Indigo carmine 0.2% and then Crystal violet 0.05% and were classified according to Kudo's pit pattern classification. Finally, polyps were resected by endoscopy or surgery and biopsy and compared with histopathological results of either neoplastic or nonplastic polyp. Results The number of neoplastic polyps was 278/332 with 231 adenoma polyps and 47 carcinoma polyps. Magnifying chromoendoscopy has high sensitivity and accuracy when compared with the histopathological results of colorectal polyps. The sensitivity, specificity, and accuracy of magnifying chromoendoscopy with Crystal violet are 97.2%, 72.2%, and 93.0%; with Indigo carmine are 96.0%, 72.2%, and 92.1%; and with FICE are 92.1%, 68.5%, and 88.3%.Conclusions Among the three methods, Crystal violet has the highest sensitivity and accuracy in predicting histopathological results of colorectal polyps. FICE has shown its diagnostic value with reliable sensitivity and accuracy and should still be a reasonable endoscopic choice for physicians in scare-setting resources regardless its moderate specificity. Physicians should base on their facility and capability to determine an appropriate endoscopy technique.

Detection Storage Time of Mild Bruise’s Loquats Using Hyperspectral Imaging

Bruise may cause spoilage, reduce commodity economic value, and give rise to food quality and safety concerns. Therefore, it is crucial to detect whether a loquat is bruised and when it is bruised to save storage and transportation costs. At present, the bruise of loquats is mainly discriminated by the operator’s naked eye, which is affected by personal habits, light intensity, and subjective psychological factors. The detection method is time-consuming, inaccurate, inefficient, and difficult to identify the bruise’s time of loquats. Due to the fact that the color features can be used to perform the conditions of the darkened and brownish regions in bruise’s loquats, the combined spectral information and the color features method is proposed to accurately detect the storage time of mild bruise’s loquats in this study. In order to reduce economic losses, different methods are used to deal with the loquats at the corresponding bruise’s time. Loquats with four types of bruise’s time, including 6, 12, 24, and 36 h, are studied. Models with four types of characteristics, including spectral information, RGB features combined with spectral information, HSI features combined with spectral information, and mixed color features combined with spectral information (mixed-spectral), are established based on linear discriminant analysis (LDA), support vector machine (SVM), and least-squares support vector machine (LS-SVM). The investigated 400 independent samples with four bruise’s time conditions are utilized to assess the classification ability of the proposed methods. The results indicate that the Mixed-RBF-LS-SVM model has the lowest errors, and the accuracies of storage time of mild bruise’s loquats at 6, 12, 24, and 36 h are 100%, 92%, 92%, and 100%, respectively. The overall accuracy of the LS-SVM model based on mixed-spectral is 96%, and it demonstrates that the combined spectral information and color features method can be used to accurately detect the bruise’s time of loquats. Finally, the LS-SVM model based on mixed-spectral is optimized by UVE, SPA, CARS, and GA, respectively; it is found that the UVE-LS-SVM model based on mixed-spectral is the best, and the overall accuracy is 92%. It also lays a foundation for future studies about detecting the bruise’s time of fruits with a high-precision, rapid, and nondestructive measurement.

Gamma-Ray Diagnostics of r-process Nucleosynthesis in the Remnants of Galactic Binary Neutron-star Mergers

We perform a full nuclear-network numerical calculation of the r-process nuclei in binary neutron-star mergers (NSMs), with the aim of estimating gamma-ray emissions from the remnants of Galactic NSMs up to 106 yr old. The nucleosynthesis calculation of 4070 nuclei is adopted to provide the elemental composition ratios of nuclei with an electron fraction Y e between 0.10 and 0.45. The decay processes of 3237 unstable nuclei are simulated to extract the gamma-ray spectra. As a result, the NSMs have different spectral colors in the gamma-ray band from various other astronomical objects at less than 105 yr old. In addition, we propose a new line diagnostic method for Y e that uses the line ratios of either 137mBa/85K or 243Am/60mCo, which become larger than unity for young and old r-process sites, respectively, with a low-Y e environment. From an estimation of the distance limit for gamma-ray observations as a function of age, the high sensitivity in the sub-megaelectronvolt band, at approximately 10−9 photons s−1 cm−2 or 10−15 erg s−1 cm−2, is required to cover all the NSM remnants in our Galaxy, if we assume that the population of NSMs by Wu et al. A gamma-ray survey with sensitivities of 10−8–10−7 photons s−1 cm−2 or 10−14–10−13 erg s−1 cm−2 in the 70–4000 keV band is expected to find emissions from at least one NSM remnant under the assumption of an NSM rate of 30 Myr−1. The feasibility of gamma-ray missions observing Galactic NSMs is also studied.

Camouflage Assessment of Aluminium Coated Textiles for Woodland and Desertland Combat Background in Visible and Infrared Spectrum under UV Vis IR Background Illumination

Aluminium powder (AP) formulated polyamide 6, 6 (PA 6, 6), cotton fabric and hollow tubular polyester beg (HTPB) were experimented for spectral, chromatic and imaging principle of woodland and desertland camouflage textiles in visible (Vis) and infrared (IR) spectrum under three-dimensional background illumination of ultraviolet (UV)-Vis-IR for concealment and detection of target signature, AP formulated fabric practiced by defense professional. Cotton and polyamide 6, 6 fabric, HTPB were coated and padded with AP powder formulated polyurethane (PU) based binder. Reflection profile of woodland combat background (CB) and coated-padded textiles have been depicted in terms of multidimensional illumination properties of Vis imaging such as chromatic intensity, spectral reflection, Kubelka-Munk (K-M) reflectance, color rendering and photonic response. A symmetrical chromatic value (L*, a*, b*) of AP coated fabric has been portrayed for concealment of target signature against woodland CB. Spectral reflection, chromatic illumination, K-M reflectance and scanning electron microscopy have also been critically confirmed five-time durability of color fastness to wash, tested by AATCC method 61-2013. HTPB-phase change material (PCM) formulation has been found temperature controllable effect of target object (TOB) in terms of heat energy at limited temperature, 30°C. Heat energy versus target concealment of IR imaging principle can be implemented for high-performance camouflage textiles design. The reflection profile of AP coated fabric can be applied for multidimensional camouflage coloration/patterning/HTPB-PCM based IR camouflage technology and direct applications of defence pavilion/tents/clothing against woodland/desertland CB. Therefore, the key phenomenon of this article has been focused on remote sensing properties of eucalyptus tree, scientific name, Eucalyptus Mannifera, a common CB of woodland and AP formulated fabric for defence application against woodland and desertland CB in terms of concealment of defence surveillance under consideration of laboratory and field trialling of woodland and desertland camouflage textiles assessment in Vis-IR spectrum. Therefore, a standardised methodology of camouflage textiles assessment for CDRI has been established under a new technique with conformist machine and technology which may be a new contribution to carry out further research and development for the fighting protection in combat environment under maintaining a standardized sequence from laboratory trialling to field experimentation in a limited timeframe of research.

Greatly enhanced deep-red luminescence performance of Ca2InSbO6:Mn4+ phosphor via multiple optimization strategies

Phosphors with high luminescence intensity, thermal stability, and spectral matching are important for indoor plant cultivation (IPC) light-emitting diodes (LEDs). Mn4+ ion-doped phosphors are considered potential deep-red emitters for plant growth LEDs. Herein, Ca2InSbO6:Mn4+ (CISO:Mn4+) phosphors were first synthesized via high-temperature solid-phase method. Their luminescence performance was greatly enhanced by using three kinds of strategies (charge compensator, solid solution, and rare earth ion co-doping). Furthermore, the optimization mechanisms were studied in depth on the basis of the principle of charge compensation and reduced quenching centers. Surprisingly, the internal quantum efficiency of the Ca1·9Y0·1InSb0·6Ta0·4O6:0.006Mn4+ phosphor was greatly enhanced to 71.4%, which was 42.75 times that of the CISO:0.006Mn4+ phosphor. Under 373 nm excitation, the Ca1·9Y0·1InSb0·6Ta0·4O6:0.006Mn4+ phosphor showed intense deep-red emission at 695 nm attributed to the 2Eg→4A2g transition of Mn4+ ions, which indicated a good match with far red phytochrome (Pfr, 84%). Finally, the fabricated IPC-LED displayed superior spectral matching, color purity (99.9%), and CIE chromaticity coordinates (0.692, 0.308). Thus, it has great potential as deep-red substitutes in the field of IPC. This work adopted a series of comprehensive strategies to optimize the luminescence performance of Mn4+-doped oxide phosphors and discussed the optimization mechanisms in depth, aiming to provide new ideas for the future optimization of phosphors.

Features of colored object detection by a person compared with using hyperspectral technology

Subject of study. The features of color discrimination by the human visual system and hyperspectral technology were considered. Aim. A quantitative analysis was performed of the color discrimination capabilities of the human visual system compared with those of hyperspectral technology. Method. The research method was based on the statistical synthesis of a three-channel detector of colored spatial objects, where the spectral characteristics of the channels were similar to those inherent in the human eye. The generalized signal-to-noise ratios obtained when detecting colored objects by hyperspectral and three-channel detectors were compared while considering only the spectral (color) differences between the object and background in the absence of any energy contrast between them. The conditions for the correct transformation of the obtained results into the conditions for the observation of colored objects by a person were determined. Main results. We demonstrated that the signal-to-noise ratio ensured by a hyperspectral detector could exceed the corresponding ratio of a three-channel detector that was structurally similar to the three-component system of color-sensitive human eye receptors by a factor of 2–400. Practical significance. The obtained results could be advantageous for camouflage or, conversely, improving the recognition of colored spatial objects observed by a person or technical device.

한국 전통 민화의 화문을 활용한 여성 레깅스 디자인 개발

초록 · 키워드 목차 오류제보하기 The purpose of this study was to develop and suggest a women"s leggings design applying the floral patterns of Korean traditional folk paintings of the Joseon Dynasty. The study was analyzed using literature and web sites regarding the flower patterns of Korean folk paintings, athleisure-look with leggings, and floral print design of leggings. The development tools of leggings designs used design CAD programs. The results of the study are as follow. First, the floral patterns of Korean traditional folk paintings had symbolic meanings expressed splendidly and richly. Second, the athleisure look was fashion that suited the lifestyle of modern people in pursuit of well-being and work-life balance. Leggings as the athleisure look was sportswear and daily wear. Third, as a result of examining floral leggings sold at the top five domestic online shopping malls, the main print design of floral leggings was totally printed with one type of floral. Fourth, five peony and five chrysanthemum paintings were selected for the leggings design. Leggings designs were tied to colorway with black color and four chromatic colors on the background. Leggings designs were developed applying items with beautiful floral patterns. The floral patterns of Korean traditional folk paintings were very aesthetic and unique resources that could be applied as print designs of leggings. #Floral patterns of Korean traditional folk paintings #Peony painting #Chrysanthemum painting #Leggings design development #Athleisure look #민화의 화문 #모란도 #국화도 #레깅스 디자인 개발 #애슬레저룩 AbstractⅠ. 서론Ⅱ. 한국 전통 민화의 화문Ⅲ. 레깅스 패션 현황Ⅳ. 화문을 활용한 레깅스 디자인 개발Ⅴ. 결론REFERENCES

A benzoxazole-based smart molecule for relay detection of zinc and phosphate ions and its implication towards molecular logic gate constructions

A benzoxazole-based fluorescent chemosensor (OPMP) has been designed, synthesized, and characterized by various analytical techniques. The as-prepared OPMP is employed for the cascade detection of Zn2+ and PO43- ions, respectively, based on the ‘off–on-off’ photoluminescence mechanism in 30% (v/v) water-DMSO mixture. A significant fluorescence enhancement of OPMP at 495 nm is observed due to chelation-enhanced fluorescence upon binding with Zn2+ ions. A visual bluish-green color could be seen under 365 nm UV light irradiation, which is also well supported by the color chromaticity diagram. The fluorescence of the Zn2+chelated OPMP complex is quenched in the presence of PO43- ions. The sensitivity of OPMP and Zn2+chelated OPMP complex towards detection of Zn2+ and PO43- ions can be possible down to 38 nM and 48 nM, respectively. Such as dual ions detection system with outstanding reversibility and reproducibility led us to consider our OPMP as a feasible candidate for the construction of molecular logic circuits, molecular keypad locks, and set-reset memorized molecular devices. Further, an OPMP staining paper strips-based test kit has been fabricated and demonstrated for the sequential detection of Zn2+ and PO43- ions, respectively.

Built environment color modulates autonomic and EEG indices of emotional response.

Understanding built environment exposure as a component of environmental enrichment has significant implications for mental health, but little is known about the effects design characteristics have on our emotions and associated neurophysiology. Using a Cave Automatic Virtual Environment while monitoring indoor environmental quality (IEQ), 18 participants were exposed to a resting state (black), and two room scenes, control (white) and condition (blue), to understand if the color of the virtual walls affected self-report, autonomic nervous system, and central nervous system correlates of emotion. Our findings showed that exposure to the chromatic color condition (blue) compared to the achromatic control (white) and resting-state (black, no built environment) significantly increased the range in respiration and skin conductance response. We also detected a significant increase in alpha frontal midline power and frontal hemispheric lateralization relative to blue condition, and increased power spectral density across all electrodes in the blue condition for theta, alpha, and beta bandwidths. The ability for built environment design to modulate emotional response has the potential to deliver significant public health, economic, and social benefits to the entire community. The findings show that blue coloring of the built environment increases autonomic range and is associated with modulations of brain activity linked to emotional processing.

Synthesis and spectroscopic properties of Er3+/Yb3+-codoped GdNbO4 phosphor for thermometry and marine safety protection

Micron-sized GdNbO4:Er3+/Yb3+ phosphors were prepared by employing a high-temperature solid-state reaction. The crystalline phase, morphology, composition, spectroscopic properties, and impact of rare-earth ion concentration, temperature and high salinity environment were systematically characterized. The extracted results show that phosphor is dominated by the existence of the GdNbO4 crystalline phase. Their morphology and agglomeration phenomenon are strongly dependent on the rare-earth concentration. The phosphor exhibits also excellent up-conversion luminescence (UCL) properties under 980 nm excitation, while a two-photon process accounts for UCL. The following optimal concentrations were selected for enhanced UCL intensity: 10 mol% for Yb3+ and 3 mol% for Er3+. The phosphor shows excellent thermometric performances including strong UCL, good thermal stability, appropriate sensitivity and a wide sensitivity response range. To evaluate the accuracy of the present optical thermometer, the temperature of a heated bench has been comparatively measured by using the proposed optical thermometer and a commercial thermocouple with an accuracy of 1 K. By comparing the temperature values measured by the two methods, it can be concluded that the present optical thermometer has an accuracy better than 1.6 K. In addition, the phosphor exhibits good chemical stability in high salinity environment. Interestingly, its crystalline phase, structure, and UCL spectral structure, intensity and color are all preserved after one-month immersion into a high salinity solution.

Color prediction of layered dental resin composites with varying thickness

ObjectiveThe aim of this study was to assess the accuracy of a Principal Components Analysis (PCA)-based method for reflectance reconstruction and color estimation of layered dental resin-based composites with different thicknesses. MethodBi-layered samples of different clinically relevant thicknesses were created using shades of VITAPAN Excell (VE), VITAPAN Dentine (VD) and VITA Physiodens (VP), combined with their corresponding enamel shades. Spectral reflectance of all samples was measured over a black background using a non-contact spectroradiometer with CIE 45∘∕0∘ geometry. Two different PCA-based models, built from two different configurations of known samples, were proposed to reconstruct the spectral data and color of unknown layered samples. Root Mean Square Error (RMSE), Goodness of Fit (GFC), as well as ΔE00 with corresponding 50:50% acceptability and perceptibly thresholds (AT and PT) were used as performance assessment. ResultsThe 5-samples training set approach provided an average RMSE < 0.015 and GFC > 0.999 when measured and predicted spectral reflectances were compared, while for the 9-samples training set, RMSE < 0.0098 and GFC > 0.9999 were obtained. The overall mean color differences obtained with the 5-samples training set approach were ΔE00 = 0.99 (AT% = 96.25% and PT% = 32.50%), while using the 9-samples training set resulted in lower overall mean color differences: ΔE00 = 0.50 (AT% = 99.22% and PT% = 83.87%). SignificanceWithin the framework of this study, the two proposed PCA-based configurations allow the prediction of the spectral reflectance of layered dental resin-based composites of different shades and thicknesses, with a high degree of accuracy.

Visual function of red staminal filaments in a bee-pollinated plant

ABSTRACT Background Floral colour is a primary signal in plant-pollinator interactions. Presumably because bees lack red receptors, bee-pollinated flowers are rarely red. Hypericum (Hypericaceae) is a genus, with yellow flowers and filaments, mainly pollinated by bees. However, one species, H. ascyron exhibits unique red filaments. Aims We tested whether the red filaments influence pollinator visitation frequency and colour perception. Methods We examined whether H. ascyron require pollinators for seed set and compared insect visitation rates of H. ascyron with those of a sympatric yellow-filamented congener. Colour perception by bees was also estimated. Results Pollinator visitation substantially enhanced seed set under natural conditions and flowers of H. ascyron had similar rates of visitation by bees as their yellow-filamented congener. Red filaments per se absorbed ultraviolet light and therefore should not be perceived as a chromatic colour by bees. The chromatic contrasts between filaments and petals as perceived by pollinators was similar between species, whereas achromatic contrasts were higher in H. ascyron. Conclusions Pure-red staminal filaments work as well in attracting potential pollinators as the yellow filaments of congeners. Based on our findings, we suggest that the evolution of red filament colour may have been driven by factors other than pollinator attraction.

Dynamics of Drying Turmeric Rhizomes (Curcuma longa L.) with Respect to Its Moisture, Color, Texture and Quality

Drying involves removing moisture from food. Therefore, to preserve the phenolic and bioactive compounds such as curcumin, dimethoxy curcumin and bisdemethoxi curcumin, etc., an efficient drying method is considered necessary. The primary drying methods are sun drying, hot air oven drying and fluidized bed drying. Traditional drying methods result in the loss of volatile oil (up to 25%) by evaporation and destruction of some light-sensitive oil constituents. Three methods of drying Turmeric with pretreatments boiled/unboiled and whole/sliced (2.5 cm long) were compared on physical and quality parameters. Texture analysis from sundry sliced boiled rhizomes achieved maximum peak force (45.40 kg), which was an indication of maximum uniform drying. Moisture content was strongly and significantly associated with drying time in different drying methods. Out of the three drying methods, in general, the sun drying showed a declining trend of L*, a* and b* values with drying time. Whereas a slower rate of decrease in L*, a* and b* values was predominant in the oven dry method. Interestingly, in the case of the fluidized method, almost static L*, a* and b* values were measured at 3 h of drying onwards after a declining trend of those values. In the case of sun and oven drying, the hue angle reached its peak at the fourth hour of drying, then gradually declined up to final drying. However, for fluidized bed drying, it had a continuous declining trend for other parameters such as chroma and total color change; there was a sharp decreasing trend for all throughout. Turmeric whole boiled dried in the sun produced the maximum curcumin (5.82%) and the sliced boiled ones produced the maximum oleoresin (8.10%), indicating good quality powdered product among all other drying treatments. Considering all the aspects, it is recommended that sun drying should be followed in post-harvest operations, as it produces a quality powder with comparatively more curcumin, despite its longer drying time.

Synthesis, photoluminescence, and up-conversion luminescence properties of YTiTaO6:Er3+/Yb3+

The relationship between the factors (i.e. the concentrations of Yb3+ and Er3+ and heating temperature in air) and the properties of photoluminescence (PL) and up-conversion luminescence of YTiTaO6:Er3+/Yb3+ whose crystalline phase depended on heating temperature in air was examined using samples synthesized hydrothermally. The intense green emission (: 2H11/2,4S3/2→4I15/2 transitions of Er3+) was obtained by the excitation at 288 ​nm using the indirect energy transfer from the YTiTaO6 host crystal, which was about 1.8 times stronger than that obtained by the direct excitation at 380 ​nm via the f-f transition (: 4I15/2→4G11/2) of Er3+. Aeschynite phase exhibited intermediate luminescence property. The up-conversion emission intensity increased with increasing heating temperature and became the maximum at x ​= ​0.10 and y ​= ​0.20 with euxenite phase, although the co-presence of Yb3+ gave negative effect on the PL intensity of ErxYbyY1-x-yTiTaO6. As heating temperature rose to 1300–1400 ​°C the intensity of the red up-conversion emission (: 4F9/2→4I15/2 transition) became greater than that of the green emission (: 4S3/2→4I15/2 transition), accordingly the position of the color chromaticity coordinates shifted slightly from green to yellow.

Chromatic Contrast Sensitivity Functions and Colour Discrimination in Smoker Patients.

In this study, effects of smoking on colour vision with the Farnsworth–Munsell 100 Hue test (FM100h) and achromatic (A), red-green (RG), and blue-yellow (BY) contrast sensitivity functions were evaluated. In total, 50 non-smoker controls and 25 smokers, divided into two groups (group 1, less than 10 cigarettes per day, with 15 patients, and group 2, >10 cigarettes per day, with 10 patients) took part in the experiments. Best-corrected visual acuity (BCVA), FM100h, and A, RG, and BY contrast sensitivity functions were measured. Total and partial RG and BY error scores (TES and PTES) and colour axis index (CA) were used in the analysis. No differences between smoker and non-smoker groups were found in BCVA, CA and A and BY contrast sensitivity, but TES and PTES values and RG contrast sensitivity at 1 cpd were statistically different. Differences between smoker groups were not significant. Error scores in smokers were positively correlated with the number of cigarettes smoked per day, and in BY also with age. Tobacco caused discrimination losses in both chromatic mechanisms but affected the red-green pathway more than the blue-yellow, and therefore, a partial RG score of FM100h test seems to be a good predictor of smoker colour deficiencies.

Blinking-Based Multiplexing: A New Approach for Differentiating Spectrally Overlapped Emitters.

Multicolor single-molecule imaging is widely applied to answer questions in biology and materials science. However, most studies rely on spectrally distinct fluorescent probes or time-intensive sequential imaging strategies to multiplex. Here, we introduce blinking-based multiplexing (BBM), a simple approach to differentiate spectrally overlapped emitters based solely on their intrinsic blinking dynamics. The blinking dynamics of hundreds of rhodamine 6G and CdSe/ZnS quantum dots on glass are obtained using the same acquisition settings and analyzed with a change point detection algorithm. Although substantial blinking heterogeneity is observed, the analysis yields a blinking metric with 93.5% classification accuracy. We further show that BBM with up to 96.6% accuracy is achieved by using a deep learning algorithm for classification. This proof-of-concept study demonstrates that a single emitter can be accurately classified based on its intrinsic blinking dynamics and without the need to probe its spectral color.