Yellow Tint Research Articles

Flavanols and Flavonols in the Nuclei of Conifer Genotypes with Different Growth

Flavanols and flavonols of mitotic and post-mitotic nuclei in needles of Taxus baccata L., Tsuga canadensis L., and slow growing dwarf genotypes of both genera are investigated histochemically. The flavanols of nuclear chromatins and in the vacuoles stain blue with the p-dimethylamino-cinnamaldehyde (DMACA) reagent. Flavonols do not react with the reagent but owing to their UV absorbance they can be seen as bright yellow pigments. The nuclei in the photomicrographs obtained by microscopy were measured for flavanols at 640 nm. The vigorously sprouting Taxus baccata L. displays the most rapid cell cycling of the needles and the nuclei reveal clear blue and white mosaic structures. The flavanol component of Taxus baccata nuclei remains relatively stable most of the growing season. The dwarf genotypes also display fairly blue stained meristematic nuclei during the intense spring flush. However, after the spring flush and towards mid-summer the nuclear flavanols slowly decrease in parallel with a gradual increase in yellow staining nuclear flavonols. A mixture of blue stained flavanols and yellow flavonols results in greenish coloration of the nuclei. The greenish tint becomes more pronounced when the parenchyma cells mature and age. At the same time, the cytoplasm of the dwarf genotypes also begins to attain a more yellow tint. This trend continues towards mid-summer and autumn, particularly in the nana genotypes. It would appear that the yellow staining flavonols are linked to restricted growth conditions. In the present study, it becomes evident that the species-typical endogenous growth potential is related to both flavanol and flavonol allocation into the nuclei. The vigorously growing species of Taxus and Tsuga have a higher capacity for recruitment of flavanols into the nuclei than the very slow growing dwarf species.

Synthesis and characterization of the Bi-for-Ca substituted copper-based apatite pigments

Substitution of Bi for Ca in the red-violet pigment Ca10(PO4)6CuyO2H2-y-δ has been studied in order to access possibilities to vary the color of the pigment. Synthesized compounds have been investigated by powder X-ray diffraction, diffuse reflectance (ultraviolet-visible-near infrared range) and Raman spectroscopy. Initial Bi-free samples contain Cu in the hexagonal channels, and a fraction of the Cu atoms constitutes recently discovered chromophore [O–CuIII–O]−-units. Bi3+ occupies Ca2+ position in the hexagonal channel walls and causes the reduction of the chromophore concentration. A small fraction of Cu2+ substitutes Ca2+ and forms a new chromophore characterized by the main absorption band at 400 nm and the resonant Raman band at 593 cm−1. Consequently, Bi-doping suppresses the initial red-violet color of the pigment while a yellow tint emerges. This may open an opportunity to develop new less-toxic yellow pigments.

8% Efficient Cu2ZnSn(S,Se)4 Solar Cells from Redox Equilibrated Simple Precursors in DMSO

selenization temperature to obtain a 900 nm CZTSSe fi lm with larger grain size. Upon full device processing on this fi lm, a solar cell with an active area power conversion effi ciency of 8.3% was achieved without an antirefl ection coating on a cell with an area of 0.43 cm 2 . These early experiments show the importance of redox reaction in solution as well as the optimization of device fabrication conditions. The improved precursor solutions were made by adding the precursors into the solvent step-by-step as shown in Figure 1 b. First, 4 mL DMSO was added to a vial containing 4 mM Cu(OAc) 2 ·H 2 O, resulting in a deep blue suspension due to very limited solubility of Cu(OAc) 2 ·H 2 O in DMSO. Second, precursor SnCl 2 ·2H 2 O (2.75 mM) was added into the vial, and the deep blue suspension gradually changed to clear light green solution after overnight stirring. Adding the third precursor ZnCl 2 (2.80 mM) into the solution resulted in further color change from light green to lighter green, with a yellow tint. Finally, 13.2 mM thiourea was added, and a transparent and colorless solution was obtained after thiourea completely dissolved. The change from deep blue suspension to a very light green-yellow clear solution after the fi rst two steps indicates reduction of Cu 2+ to Cu + (Equation (1)) accompanied by solvation/stabilization of metal ions by DMSO and/or chloride anions. The fi nal colorless solution indicates that little Cu 2+

Automatic glare removal in endoscopic imaging

Glare from surgical instruments and tissue surfaces often occurs during endoscopic procedures and can be disturbing to the operator. The brightness level of the light source can be reduced, but at the expense of overall image clarity, so alternative solutions are needed for removing glare. Digital image-processing methods offer the opportunity to lessen or eliminate glare by reducing the intensity of the affected parts of the image. This study investigated a new automated method for glare reduction that uses two different intensity thresholds as a basis for applying glare reduction processes and it also reduces unpleasant artifacts at the glare region boundaries. The new glare-reduction method was compared with a previous method. Three variants of each method, each with different color biases in the glare regions, were applied to a 20-s surgical recording containing substantial amounts of glare. The six versions and the original recording were evaluated subjectively by a group of 10 experienced surgeons using a paired-comparisons method, in which each version was compared for preference with all the other versions. The new double-threshold intensity-subtraction method scored significantly higher than the previously developed glare-reduction method (p<0.05). It also scored higher than the original (unprocessed) version, but not significantly. The color bias was important, with combinations of pink and grey performing better than yellow tints. The findings show the new method to be a significant improvement in automatic glare reduction compared with earlier methods. The method is not computationally demanding, so it can in the future be evaluated clinically in high-definition endoscopic imaging systems and developed further in this environment.

An assay for functional xylose transporters in Saccharomyces cerevisiae

It has been considered that more efficient uptake of xylose could promote increased xylose metabolic capacity of several microorganisms. In this study, an assay to screen xylose transporters was established in the Saccharomyces cerevisiae strain, which expresses the xylosidase gene of Bacillus pumilus intracellularly. The absorbed xylose analog p-nitrophenyl-β-d-xylopyranoside (pNPX) rapidly hydrolyzed to p-nitrophenol (pNP), which displayed a yellow tint when exposed to xylosidase in vivo. The xylose transporter activities of the strain were computed using the pNP production rate, which was detected extracellularly. This method could be used for both high-throughput screening and smaller scale investigations. AraEp, which is a pentose transporter of Corynebacterium glutamicum, was expressed in S. cerevisiae and exhibited better transport capacity than the endogenous transporters Hxt7p and Gal2p. Moreover, a mutant of AraEp with 103% greater transport capacity was screened out, and the computer simulation suggested that transmembrane domain 5 was an important factor for the transport capacity of AraEp in S. cerevisiae.

Phenolic compounds from roots of Rhodiola litvinovii

Plants of the genus Rhodiola (Crassulaceae) typically have a high content of biologically active compounds. R. rosea (golden root) is a medicinal plant that is used in folk and modern medicine. Therefore, it seemed interesting to study other species of Rhodiola. Four species of this genus are indigenous to Uzbekistan [1]. The chemical composition of the population of R. litvinovii Boriss. growing in Uzbekistan is practically unstudied [2]. Six phenolic compounds were isolated previously from a population of this plant growing in Siberia (Russia) [3–5]. We studied roots of R. litvinovii collected during flowering in the western Tien-Shen (Pskem Range, Bostandyk District, Tashkent Region, RU) in September 2010. For this, roots of R. litvinovii (2000 g) were extracted exhaustively with EtOH (40%) at room temperature by percolation (24 h). The combined extracts were evaporated in vacuo. The condensed thick residue (0.7 L) was diluted with H2O (1:1) and worked up successively with petroleum ether, CHCl3, EtOAc, and n-BuOH. The condensed EtOAc extract was placed on a chromatography column of silica gel that was eluted sequentially with CHCl3 and CHCl3:MeOH mixtures of various proportions. The resulting separate eluates were re-chromatographed over Sephadex LH-20 with elution by H2O:MeOH mixtures with increasing gradient of MeOH. The chromatographic separation isolated four known compounds that were identified by comparing their IR, UV, PMR, and 13C NMR spectra with the literature. p-Tyrosol (p-hydroxyphenyl-ethanol) (1), white needle-like crystals, C8H10O2, mp 94–95°C (CHCl3:MeOH, 4:1). UV spectrum (MeOH, max, nm): 204.36, 223.93, 278.27. IR spectrum (KBr, , cm –1): 3390–3144 (OH), 2879 (CH2), 1613, 1598, 1513 (aromatic ring), 817 (p-substituted benzene ring). 13C NMR spectrum (100 MHz, CD3OD, , ppm): 131.20 (C-1), 130.99 (C-2), 116.28 (C-3), 156.88 (C-4), 116.28 (C-5), 130.99 (C-6), 39.54 (C-7), 64.72 (C-8) [6, 7]. Salidroside [p-hydroxyphenyl-( -D-glucopyranosyl)-ethanol] (2), white amorphous powder with a yellow tint, C14H20O7, mp 163–164°C (CHCl3:MeOH:H2O, 26:14:3). UV spectrum (MeOH, max, nm): 203.06, 223.90, 277.60. IR spectrum (KBr, , cm–1): 3596-3271 (OH), 2933, 2878 (CH2), 1883, 1615, 1518 (benzene ring), 1241 (phenol hydroxyl), 1073, 1023 (pyranoside), 900 ( -glycoside bond). 13C NMR spectrum (100 MHz, CD3OD, , ppm): 131.06 (C-1), 130.80 (C-2), 116.25 (C-3), 146.51 (C-4), 116.25 (C-5), 130.80 (C-6), 36.50 (C-7), 71.77 (C-8), 104.49 (C-1 ), 72.23 (C-2 ), 78.07 (C-3 ), 71.77 (C-4 ), 78.22 (C-5 ), 62.88 (C-6 ) [8]. Gallic acid (3), crystals, very soluble in alcohol and hot water, C7H6O5, mp 238–240°C. UV spectrum (EtOH, max, nm): 211, 274, Rf 0.65 (BAW, 4:1:2), 0.34 (2% AcOH); gave a blue color with iron chloride solution (1%). Identification of gallic acid (3) was confirmed by an XSA. (–)-Epigallocatechin-3-O-gallate (4), brown amorphous powder, C22H18O11, mp 210–211°C. UV spectrum (MeOH, nm): max 205, 275; min 255. IR spectrum (KBr, , cm –1): 3386, 2929, 1728, 1616, 1527, 1451, 1283, 1206, 1046, 776. 13C NMR spectrum (100 MHz, CD3OD, , ppm): 77.22 (C-2), 68.56 (C-3), 25.42 (C-4), 155.83 (C-5), 95.19 (C-6), 156.48 (C-7), 94.53 (C-8), 156.42 (C-9), 98.08 (C-10), 129.44 (C-1 ), 105.54 (C-2 ), 144.89 (C-3 ), 132.40 (C-4 ), 145.29 (C-5 ), 105.54 (C-6 ), 120.17 (C-1 ), 108.91 (C-2 ), 144.89 (C-3 ), 138.39 (C-4 ), 145.29 (C-5 ), 108.91 (C-6 ), 166.20 (COO) [9, 10]. These compounds were isolated for the first time from this plant species.

Cortinarius section Sanguinei in North America

The North American species of Cortinarius section Sanguinei were studied using morphological characters and ITS and RPB2 sequence data. Several type collections also were examined. Four species were identified: C. harrisonii sp. nov, C. neosanguineus sp. nov., C. sanguineus and C. sierraensis comb. nov. Of these, C. sanguineus also occurs in Europe together with C. puniceus, a fifth member of the section. Typical features of these species include ± red, fairly small basidiomata, stipe basal mycelium often with yellow to reddish yellow tints, amygdaloid to ellipsoid spores, and aniline-red lamellar trama and pileipellis hyphae when mounted in KOH. Two other species with red lamellae C. marylandensis comb. nov. and C. smithii stat. nov. & nom. nov. also are discussed.

A Yellow Filter Improves Response Times to Low-Contrast Targets and Traffic Hazards

Anecdotal evidence suggests that some sunglass users prefer yellow tints for outdoor activities, such as driving, and research has suggested that such tints improve the apparent contrast and brightness of real-world objects. The aim of this study was to establish whether yellow filters resulted in objective improvements in performance for visual tasks relevant to driving. Response times of nine young (age [mean ± SD], 31.4 ± 6.7 years) and nine older (age, [mean ± SD], 74.6 ± 4.8) adults were measured using video presentations of traffic hazards (driving hazard perception task) and a simple low-contrast grating appeared at random peripheral locations on a computer screen. Response times were compared when participants wore a yellow filter (with and without a linear polarizer) versus a neutral density filter (with and without a linear polarizer). All lens combinations were matched to have similar luminance transmittances (~27%). In the driving hazard perception task, the young but not the older participants responded significantly more rapidly to hazards when wearing a yellow filter than with a luminance-matched neutral density filter (mean difference, 450 milliseconds). In the low-contrast grating task, younger participants also responded more quickly for the yellow filter condition but only when combined with a polarizer. Although response times increased with increasing stimulus eccentricity for the low-contrast grating task, for the younger participants, this slowing of response times with increased eccentricity was reduced in the presence of a yellow filter, indicating that perception of more peripheral objects may be improved by this filter combination. Yellow filters improve response times for younger adults for visual tasks relevant to driving.

Expression and purification of recombinant tung tree diacylglycerol acyltransferase 2.

Diacylglycerol acyltransferases (DGATs) esterify sn-1,2-diacylglycerol with a long-chain fatty acyl-CoA, the last and rate-limiting step of triacylglycerol (TAG) biosynthesis in eukaryotic organisms. At least 74 DGAT2 sequences from 61 organisms have been identified, but the expression of any DGAT2 as a partial or full-length protein in Escherichia coli had not been reported. The main objective of this study was to express and purify recombinant DGAT2 (rDGAT2) from E. coli for antigen production with a minor objective to compare rDGAT2 expression in yeast. A plasmid was engineered to express tung tree DGAT2 fused to maltose binding protein and poly-histidine (His) affinity tags. Immunoblotting showed that rDGAT2 was detected in the soluble, insoluble, and membrane fractions. The rDGAT2 in the soluble fraction was partially purified by amylose resin, nickel-nitrilotriacetic agarose (Ni-NTA) beads, and tandem affinity chromatography. Multiple proteins co-purified with rDGAT2. Size exclusion chromatography estimated the size of the rDGAT2-enriched fraction to be approximately eight times the monomer size. Affinity-purified rDGAT2 fractions had a yellow tint and contained fatty acids. The rDGAT2 in the insoluble fraction was partially solubilized by seven detergents with SDS being the most effective. Recombinant DGAT2 was purified to near homogeneity by SDS solubilization and Ni-NTA affinity chromatography. Mass spectrometry identified rDGAT2 as a component in the bands corresponding to the monomer and dimer forms as observed by SDS-PAGE. Protein bands with monomer and dimer sizes were also observed in the microsomal membranes of Saccharomyces cerevisiae expressing hemagglutinin-tagged DGAT2. Nonradioactive assay showed TAG synthesis activity of DGAT2 from yeast but not E. coli. The results suggest that rDGAT2 is present as monomer and dimer forms on SDS-PAGE, associated with other proteins, lipids, and membranes, and that post-translational modification of rDGAT2 may be required for its enzymatic activity and/or the E. coli protein is misfolded.

Difference Analysis of Different Standard Illuminants on Yellow-Green to Green Jadeite-Jade

Under A, CWF, D55, D65, D75 five different illuminants, color differences of 53 natural oval Jadeite-jade with fine texture are analyzed, which color is yellow-green to dark green. All 5 tested lighting sources were compared based on the uniform color space CIE 1976L*a*b*. Jadeite-jade’s lightness L* is increasing when color temperatures of five different standard illuminants increase, and it can reach the very top of 45.72 under D75, so it appears brighter and lighter than any other illuminants and it influences the appraisal of the samples’ color. The spectrum power distribution of D75, D65 and D55 reveal the strong radiant energy in the range from 500 to 570nm, so consequently the color coordinates a*, b* and chroma C* is higher than the other two illuminants. But samples’ lightness and chroma under D55 are weaker compared to D65 and the color under D55 is dark. Meanwhile, D65 stands for the average daylight and color under D65 close to the true color of samples. Because of weakest radiant energy in the range from 500 to 540nm (green area) and strongest radiant energy in the range from 540 to 570nm (orange area) in CWF’s spectrum power distribution, the absolute value of a*=14.01 is lowest and b*=12.93 is highest under CWF, so samples’ color under CWF is green with a yellow tint. The maximum hue angle h0 is 150.42 under A, and the absolute value of a* is higher than that under CWF, so it shows stronger green tone than CWF. It is concluded that D65 is preferred to be ideal illuminants for the evaluation of jadeite-jade color green especially compared with other 4 illuminants.

Optical properties of the black diamond produced by ion implantation

Abstract

Advantages of Nano Pigments Over Micro Pigments in Obtaining Larger Spectra of Colours in CMYK System

Based on the CMYK colour system, it is possible to obtain the full colour spectrum with mixing the four colours – cyan, magenta, yellow and key (black). In this research, ceramic nano pigments including CoAl2O4 (cyan), Au (magenta), (Ti,Cr,Sb)O2 (yellow) and CoFe2O4 (key) were mixed together with different ratios and applied on glazed tiles and the colour specifications of the samples were measured. The Colours Software (CSA) was used for predicting the ratios of the pigments for obtaining a target or reference colour. For comparison, equivalent micro pigments, namely CoAl2O4, Cd(S,Se):ZrSiO4, (Ti,Cr,Sb)O2 and CoFe2O4 were also examined. It was observed that using the present nano pigments, it was possible to cover the fourth quarter of the CIELab circle close to a + axis, while this was not possible with the micro pigments. This was attributed to the blue tint present in Au nano pigment. It was also revealed that reaching the colours of grey, brown and beige shades was possible by both nano and micro sets of pigments, while making orange and yellow colours was difficult. Also, it was revealed that yellow nano and micro pigments did not have thermal stability at high temperatures. The results indicated that nano pigment with 4.592 < a * < 15.606 and −1.560 < b * < +1.549 had yellow and blue tints and its yellow tint was due to grain growth, but micro pigment showed more red and less yellow tint. The above mentioned a* and b* values indicate the high colour performance of the pigment.

Growth Performance, Carcass Characteristics and Meat Quality of Boer-Cross Wether and Buck Goats Grazing Marshall Ryegrass

An experiment was conducted to evaluate the effects of castration on growth performance, carcass characteristics, and meat quality of goat kids. Fourteen Boer-cross buck and wether goat kids (n = 7; initial body weight (BW) and , for bucks and wethers, respectively) were grazed on annual Marshall ryegrass (Lolium multiflorum Lam.) for 56 days. Body weights were recorded after 4 h withdrawal from feed and water for two consecutive days, every 2 wk. After d 56, animals were harvested and hot carcass weight (HCW), cold carcass weight (CCW), dressing percent (DP), kidney and pelvic fat (KPF), longissimus muscle (LM) area, back fat (BF), and other carcass parameters were measured. Day 0 BW was used as a covariate for analyses. However, bucks were heavier than wethers at d 15 (p = 0.09), 42 (p = 0.001) and 56 (p = 0.001). Bucks had higher ADG (146 vs. 74 g/d; p = 0.001), HCW (21.2 vs. 18.8 kg; p = 0.06) and CCW (20.3 vs. 17.9 kg; p = 0.04) when compared with wether goats. Dressing percentage (51 vs. 47%; p = 0.06), KPF (0.44 vs. 0.16%; p = 0.02) and BF (0.41 vs. 0.21 cm; p = 0.05) were higher in wethers vs bucks, respectively; however, USDA live or carcass grades were similar. Longissimus muscle tissue from wethers and bucks were similar in darkness () and redness (), but wethers had more (p = 0.02) yellow tint (). Palmitic (C16:0), stearic (C18:0) and oleic (C18:1) acids were higher (p = 0.001) in muscle tissue from wethers compared to bucks. The saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA) contents of muscle tissue were lower (p = 0.001) for bucks with no difference in polyunsaturated fatty acids (PUFA). Longissimus muscle initial temperature was higher in bucks (p

Carbohydrates from the aerial and subterranean parts of Curcuma longa

Curcuma longa L. is a perennial herbaceous plant of the family Zingiberaceae and is indigenous to South Asia, tropical Australia, etc. The principal raw material of C. longa is the rhizomes, yellowish-gray on the outside, golden-yellow in cross section. The pear-shaped or egg-shaped I order rhizomes or cylindrical side runner II order rhizomes are used commercially. Rhizome powder is widely used as a spice to improve the taste of food, to give it a yellow color, and to improve digestion. It exhibits cholegogic, diuretic, and stimulant activity [1–4]. Our goal was to study the content and composition of the carbohydrates depending on the introduction site, in particular, under Tashkent oasis conditions. We studied air-dried powdered I and II order rhizomes, roots, and leaves. Lipophilic compounds were isolated from raw material by treatment with CHCl3:EtOH (2:1, v/v). Then sugar soluble in alcohol (SSA) was isolated by EtOH (82%). The SSA content was dominant in II order rhizomes (11.8%). The SSA composition was analyzed by descending PC on FN-13 paper using n-BuOH:Py:H2O (6:4:3). Sugars were identified using anilinium acid phthalate (hexoses) and alcoholic urea (5%, ketoses). The SSA contained arabinose, glucose, and fructose. The raw material remaining after SSA isolation was extracted exhaustively with water at room temperature, oxalic acid and ammonium oxalate (1:1) solutions (0.5%) at 70°C, and aqueous base (5%). The aqueous and acidic extracts were condensed and precipitated by EtOH to afford the corresponding water-soluble polysaccharides (WSPS) and pectinic compounds (PC). The basic extract was neutralized with CH3COOH, dialyzed against tapwater, evaporated, and treated with alcohol (three times the volume) to isolate hemicellulose (HC). The monosaccharide compositions of the polysaccharide fractions were determined after acid hydrolysis (H2SO4, 2 N, 100°C, 5–12 h). The hydrolysates were treated with BaCO3 until neutral, filtered, evaporated, and analyzed by PC and GLC. Sugars were identified using markers. GLC scans were recorded on a Chrom-5 chromatograph with a flame-ionization detector, glass column (250 0.20 mm), 5% Silicone XE-60 on inerton, super-grain (0.16–0.20 mm), 205°C, N2 carrier gas, 30 mL/min. Sugars were analyzed as aldononitrile acetates [5]. Table 1 presents the polysaccharide (PS) content and its monosaccharide composition. It can be seen that PS were distributed differently in various plant organs. There were more PS in I-II order rhizomes than in roots and leaves. The dominant PS in all plant organs were base-soluble PS, i.e., HC. The WSPS content in various organs was 0.86–2.6%; in roots, traces. The principal WSPS monosaccharide of I order rhizomes and leaves was glucose. Mainly xylose, mannose, and glucose were detected in the WSPS hydrolysate of II order rhizomes. WSPS of rhizomes were a friable white powder with a yellow tint that was soluble in water to form a slightly cloudy solution. The aqueous solution of PS gave a positive test with iodine. This suggested that the PS were glucans. Glucose dominated in the hydrolysate. Table 1 shows that PC accumulated in rhizomes. Their principal monosaccharide was glucose. There were less PC in roots and leaves. Glucose also dominated. This was consistent with the presence of starch (positive test with iodine). The isolated PC were a white powder with a yellow tint that dissolved with heating in water and formed viscous solutions. The PC differed from each other qualitatively and quantitatively. Galacturonic acid, arabinose, xylose, and glucose were detected in the PC hydrolysates.

The Effect of Masterbatch Addition on the Mechanical, Thermal, Optical and Surface Properties of Poly(lactic acid)

There has been considerable interest in the use of the biodegradable polymer poly(lactic acid) (PLA) as a replacement for petroleum derived polymers due to ease of processability and its high mechanical strength. Other material properties have however limited its wider application. These include its brittle properties, low impact strength and yellow tint. In an attempt to overcome these drawbacks, PLA was blended with four commercially available additives, commonly known as masterbatches. The effect of the addition of 1.5 wt% of the four masterbatches on the mechanical, thermal, optical and surface properties of the polymer was evaluated. All four masterbatches had a slight negative effect on the tensile strength of PLA (3–5% reduction). There was a four fold increase in impact resistance however with the addition of one of the masterbatches. Differential scanning calorimetry demonstrated that this increase corresponded to a decrease in the polymer crystallinity. However there was an associated increase in polymer haze with the addition of this masterbatch. The clarity of PLA was improved through the addition of an optical brightener masterbatch, but the impact resistance remained low. The glass transition and melting temperatures of PLA were not affected by the addition of the masterbatches, and no change was observed in surface energy. Some delay in PLA degradation, in a PBS degradation medium at 50 °C, was observed due to blending with these masterbatches.

Low vision rehabilitation for a target-shooting marksman with visual field loss and diplopia

Background In the United States in 2006, there were 17.8 million hunters and 17.1 million target shooters. When these sportsmen suffer significant visual loss, it can have a devastating effect on their participation in the shooting sports. According to the National Rifle Association, there are no reliable data sources on the number of target shooters with visual impairment. This case report describes a retired, nationally ranked, competitive target shooter who suffered bilateral visual field loss secondary to nonarteritic anterior ischemic optic neuropathy and diplopia secondary to cerebral vascular accident. Case report A retired 67-year-old white man was referred by a local optometrist to a neuro-ophthalmologist with a suspicious finding of disc pallor and a restriction of the visual field. Examination revealed right hypertropia and visual field defects: binocular superior altitudinal losses and inferior arcuate loss in his dominant, right eye. He had best-corrected distance acuity of 20/20 − 2 in the right eye and 20/25 − 2 in the left eye. Because of this, he received several adaptive rehabilitation devices to help him regain his shooting performance. These included a single-vision add for the pistol sight, yellow tint, low-power telescope, and patching. In this report, the fundamentals of eye care for competitive shooting are described with an emphasis on providing the best acuity for presbyopic patient prescriptions at nonstandard distances and the avoidance of diplopia. Conclusion A visually impaired sportsman who participated in shooting sports at a high level was attempting to return to his previous shooting performance. This case report shows how sports vision and low vision rehabilitation techniques can improve the visual function of a competitive shooter.

Vihorlatite, Bi24Se17Te4, a new mineral of the tetradymite group from Vihorlat Mts., Slovakia

Vihorlatite, ideally Bi 24 Se 17 Te 4 , is a new mineral species found in the region of volcanic Vihorlat Mountains in eastern Slovakia. It occurs in quartz-opal veinlets or secondary quartzites as anhedral to subhedral grains flattened parallel to (0001) up to 8 mm in diameter or aggregates thereof. The mineral is steel grey in colour and shows a metallic lustre. It displays a perfect cleavage along (0001) and shows deformation lamellae in mechanically bent crystals. In reflected light, it is white with a yellow tint, bireflectance is not perceptible in air, and anisotropy is moderate varying from light yellow-grey to dark grey. Maximum and minimum values of reflectance measured in air for 470, 546, 589 and 650 nm are ( R max / R min in %): 52.9/49.9, 54.5/50.6, 54.6/51, 54.7/51.2. Vickers micro-hardness (VHN 50 in kg/mm 2 ) varies in the range 49.2 – 91.7 with mean value of 65.9. Average chemical composition (in wt. %) Bi 71.5, Se 21.4, Te 8.1, S 0.8, Au 0.01, Ag 0.01, Sb 0.04, total 101.86, results in an empirical formula Bi 21.9 Se 17.4 Te 4.1 S 1.6 . The mineral is trigonal, with space group P 3 m 1. The unit-cell dimensions refined from powder data are a = 4.2797(9) A and c = 87.01(2) A with c / a = 20.332(6) and V = 1380.2(6) A 3 . For Z = 1, the calculated density is D x = 7.850(3) g/cm 3 , measured density D m = 8.0(2) g/cm 3 . The five strongest diffraction lines are [ d (A), I / I 0 , ( hkl) ]: 4.55, 55.4, (0.0.19); 3.116, 100, (1.0.15); 2.282, 75.5, (0.1.30); 1.934, 42.8, (1.1.19) (0.0.45); 1.767, 31.5, (0.2.15). The crystal structure of vihorlatite is derived from that of Bi 8 Se 7 archetype. Vihorlatite belongs to the tetradymite group.

Waterborne latex coatings of color: III. Triblock polyether influences on color development and viscosity

Oxyethylene (PEO)/oxypropylene (PPO) triblock polymers are added to colorant formulations to determine the influence of molecular weight and other structural variances on the rheology and color development of tinted latex paints. Waterborne coatings are a matrix of many coating components. In this study, a 108- or a 600-nm latex was thickened with a nonassociative thickener, hydroxyethyl cellulose, or an associative telechelic HEUR thickener. Triblock polymers with internal PPO segments and PEO terminal segments added as a dispersant to colorant packages, lead to better color development than PPO/PEO/PPO triblocks dispersants in carbon black (CB) tinted paints. The increase in color development with high molecular weight (MW) triblocks starts at a very low concentration (2 mM) and plateaus in a Langmuir-type adsorption isotherm. Lower molecular weight triblock polymers also exhibit this behavior in CB-, red-, and yellow-tinted latex coatings; however, increasing the terminal PEO segment sizes leads to better color development only in the CB-tinted coatings. With large PEO terminal units red and yellow tints are high only at very low concentrations (2 mM) of the triblock. This parabolic response in color development, in contrast to CB-tinted formulations, is attributed to the high surface area and porosity of CB that limits the amount of large PEO segments interacting with the talc particle present at twice the volume fraction of the colorant. With the lower surface areas of the red and yellow colorants, the interaction of the large PEO terminal segments with talc particles accounts for the limited triblock concentration for which good color development is observed. This can be reversed by decreasing or eliminating talc from the formulation.

Production of nanoparticles of copper compounds by anodic dissolution of copper in organic solvents

The anodic behaviour of copper was investigated in ethanol solution containing LiClO4, LiCl electrolyte and water. The type of electrolyte and the water content influences the mechanism of the anodic process and the formation of anodic products. In LiClO4 electrolyte the dissolution of copper is related to the oxidation of Cu(I) to Cu(II). In solutions of LiCl the etching of copper begins with the creation of soluble complexes of Cu(I) with chloride ions and solvent molecules. At potentials above 0.4 V the formation of alkoxides was observed in both solutions, characterized by a yellow tint. On the other hand, above 0.8 V (i.e. above the equilibrium potential of alcohol oxidation) copper dissolution is accompanied by the formation of a blue colloidal suspension of Cu (II) copper salt. Anodic etching of copper in solutions containing 3% H2O at potentials higher than 0.4 V leads to the formation of colloidal suspension of copper oxide nanoparticles.

Telluronevskite, Bi3TeSe2, a new mineral

The new mineral telluronevskite, ideally Bi 3 TeSe 2 , has been found as irregular grains disseminated in quartzite from the volcanic Vihorlat Mts near Kosice in eastern Slovakia, Slovak Republic. The mineral forms massive aggregates up to 2 mm in diameter and/or individual disseminated tabular crystals flattened along (0001). Telluronevskite is megascopically steel grey in colour, with a metallic lustre and black streak. In reflected light, it is white with a yellow tint, very weak pleochroism and moderate anisotropy. Maximum and minimum values of reflectance measured in air for 470, 546, 589 and 650 nm are ( R max / R min in %): 48.5/46.6; 51.1/48.5; 51.9/49.5; 52.8/50.5. Vickers micro-hardness (VHN 10 in kp.mm −2 ) varied in the range 63-137 with mean value of 100. Microprobe analyses yield the empirical formula (Bi 2.92 Pb 0.02 )Te 1.01 (Se 1.73 S 0.32 ). It is trigonal with space group P 3 m 1. The unit-cell dimensions refined from X-ray powder microdiffraction data are a = 4.264(6) A and c = 23.25(3) A with c : a = 5.453 : 1. For Z = 2 the calculated density is D x = 8.08(2) g.cm −3 ; measured density D m = 8.1(2) g.cm −3 . The five strongest lines in the diffraction pattern are ( d (A), I/I 0 , hkl ): 4.66, 19, 005; 3.12, 100, 104; 2.28, 33, 108; 2.13, 36, 110, 109; 1.355, 18, 1.0.16, 214. Constrained structure refinement from combined powder and precession data revealed ordering of Te and Se atoms within the telluronevskite crystal structure. Telluronevskite belongs to the tsumoite subgroup of the tetradymite group.