Amber Color Research Articles

Early ontogeny of coal grunter from hormone‐induced spawnings and laboratory‐reared embryos and larvae

Spawning of coal grunter Hephaestus carbo was successfully induced using doses of human chorionic gonadotrophin (hCG) between 500 and 3000 IU kg (body weight)−1. Water hardened eggs are telolecithal, amber in colour, spherical, transparent, demersal and slightly adhesive with a single large oil droplet and perivitelline space 47% of total egg volume. Cleavage begins 10–15 min after fertilization. Epiboly begins 6h after fertilization and continues for 4 h. Invagination of the neural tube is apparent 11·5 h after fertilization, followed by progressive organogenesis up to hatching 60–80 h after fertilization. An invagination in the yolk, consistent in shape, position and time of appearance among embryos spawned from numerous brood stock pairs, was visible in all fertilized eggs between neurulation (11‐5 h) and early organogenesis (20 h). The functional significance of this yolk invagination is unknown. Newly‐hatched larvae (4·2 mm LT) are elongate and possess well developed eyes, a functional mouth, and a large yolk sac. Yolk is fully resorbed and first feeding occurs at 6 days posthatching. The sequence of fin formation is caudal, second dorsal and anal, first dorsal, pectoral and pelvic. The prefiexion larval stage lasts for c.8 days and flexion of the notochord is complete within a further 8–9 days. Squamation commences at 30 days posthatching and transition to the juvenile life stage is complete by 35–40 days posthatching.

Annual cycle of the speckle pattern on the carapace of immature hawksbill turtles (Eretmochelys imbricata) in Cuba

AbstractThe black speckles in the carapace surface pattern of the hawksbill turtle go through two periods of development: one is the formation period and the other is a period of less formation, and these periods occur once a year. The results of this study show that these cycles have nothing to do with genetics or the growth of the shell. These cycles are highly correlated with the changes in the water surface temperature in the sea near Cuba. The black-speckle formation period falls before and after March, which is the dry season (a low-temperature period), while the amber color area tends to take shape during the wet season (high-temperature) in Cuba.

Special Flashing Warning Lights for Construction, Maintenance, and Service Vehicles: Are Amber Beacons Always Enough?

Ways to improve the Texas Department of Transportation’s (TxDOT’s) current vehicle warning light policy were researched. Tasks included a survey of motorist perceptions of different warning light color combinations and also field studies of the effect of selected color combinations on traffic behavior. The motorist survey, conducted at driver licensing stations in Dallas–Fort Worth, San Antonio, and Houston, indicated that the combination of blue and amber lights implied a slightly greater sense of hazard to motorists than did the amber light alone. However, this greater sense of hazard did not necessarily translate into differences in how motorists believed they needed to respond. Field studies conducted at freeway locations in San Antonio and Houston investigated the effect of selected, alternative vehicle warning-light color combinations on vehicle speeds, lane choice, and braking activity. Researchers found significant reductions in speeds at a few sites—but not all—for the amber and blue warning light color combination when compared with speeds observed when only an amber warning light was used. In addition, the data suggested a trend toward increased brake usage for the red, amber, and blue light configuration compared with the amber-light-only configuration. There also was evidence that the amber-and-blue light configuration slightly increased the frequency of brake applications. Furthermore, the use of a law enforcement vehicle during testing resulted in significantly more brake-light activations than did a TxDOT courtesy patrol vehicle outfitted with the same warning light colors.

Growth of Bi 12SiO 20 single crystals by the pulling-down method with continuous feeding

Bi 12SiO 20 single crystals were successfully grown by the pulling-down method with continuous feeding. As-grown crystals were amber in color and transparent, and had no cracks or inclusions. A crystal with homogeneous composition was obtained from Bi-rich feed powder having a composition of 14.1 mol% SiO 2, whereas precipitates of Bi 4Si 3O 12 were observed on the surface of a crystal grown with stoichiometric powder. The shape of the solid–liquid interface during the crystal growth was estimated to be almost flat, which was favorable to avoid core formation. Average dislocation density was 4×10 3/cm 2, which was comparable to that of Bi 12SiO 20 crystals grown by the Czochralski method.

Seed characteristics of plant species from riverine wetlands in Venezuela

Seed characteristics of 76 plant species from wetlands along four black-water and two white-water rivers in the Southeastern Venezuelan Llanos were examined. Weight, length, width, color, appendages, shape, and dispersal type of seeds were determined. Life form, leaf type and fruit type of plants also were described. Thirty-eight percent were perennial heloculms, 28% helosuffrutescents, 13% heloterophytes and 5% annual heloculms. Dominant leaf types were nanopylls and microphylls. Ninety-six percent of species showed dehiscent and indehiscent dry fruits (achene, capsule, nutlet, follicle). Sixty-five percent of species had seed dry weights between 32 and 315 μg. Lengths and widths of the seeds ranged from 0.2 to 6.2 mm and 0.1 to 4.1 mm, respectively. Seventy-six percent of species had seeds reddish brown, yellowish brown and amber in color, with 17% black and 7% white. Seventy-seven percent of species had seeds represented by pterochory, pogonochory, sclerochory, desmochory, and pleochory dispersal types, with 11% sarchochory, and 12% barochory. The seed size showed significant differences among families, life forms, geometric shapes and dispersal types. In general, species from wet and open environments (marshes) along black- and white-water rivers showed low variation in seed color and size, and were dispersed mainly by abiotic agents.

Effects of pyriproxyfen on engorged females and newly oviposited eggs of the lone star tick (Acari:Ixodidae).

Engorged females and 1- to 3-d-old eggs of the lone star tick, Amblyomma americanum (L), were exposed to 9 treatments of pyriproxyfen (4, 8, and 16 micrograms/cm2) in glass vials at exposure periods of 7 d, 14 d, and continuous at each dosage level. Treatment of newly engorged females did not affect the number of females ovipositing, but the number of eggs oviposited decreased as dosage and exposure time increased. Complete inhibition of egg hatch occurred at all treatment levels except that of the lowest dosage and exposure time where 99.9% inhibition was observed. Egg masses from treated females contained eggs that turned a dark amber color and imploded, retained normal shape and color without visible evidence of embryogenesis, or had developed embryos that were unable to emerge. Treatments of 1-to 3-d-old eggs were effective in reducing hatch and larval survivorship to 25 d after emergence only at the continuous exposures of dosages of 4, 8, and 16 micrograms/cm2. Larvae emerging from eggs treated at the lower dosage rates of 0.2 and 0.02 microgram/cm2 were as successful in feeding on chickens and subsequently molting as acetone treated control ticks.

Toxicity of aspen wood leachate to aquatic life: Laboratory studies

AbstractTrembling aspen (Populus tremuloides Michx.), a common hardwood tree throughout Canada, is being harvested at increasing rates for use in paper and building materials. Piles of aspen logs have been observed to produce a dark, watery, acutely toxic leachate. A laboratory study was undertaken to elucidate the nature, strength, and persistence of aspen leachate toxicity and the chemical composition of the leachate. Leaching from aspen chips in the laboratory was rapid, with 1% mass loss in the first 24 h. Another 2 weeks of immersion was necessary to remove all remaining leachable material (3% total). Fresh aspen leachate derived from a 1:9 wood‐water mixture (35 d immersion) was characterized by amber color, low pH (4.0), extremely high BOD (>2,600 mg/L), and high conductivity (1140 μS/cm). The leachate was rich in phenols (30 mg/L), organic carbon (2,480 mg/L), and organic nitrogen (13 mg/L). Median acutely toxic concentrations of leachate were consistently 1 to 2% of full strength for trout and Daphnia. Inhibition of bacterial metabolism began at concentrations below 0.3%. Leachate was less toxic to plant life but inhibited algal growth at concentrations of 12 to 16%. Toxicity of aspen leachate persisted at the same level as in fresh leachate for more than 2 months unless artificial aeration was provided. Persistence was even greater at low temperature (5°C). Aged leachate underwent a transition marked by a rise in pH and dissolved oxygen concentration, a small decline in conductivity, and a color change, from amber to black. Toxicity declined abruptly when the supply of labile toxicants was exhausted, but it sometimes increased again from the products of microbial metabolism. Oxygen depletion, low pH, and phenolic compounds contribute to the toxicity of aspen leachate, but much of the toxic effect must be attributed to other, unidentified constituents.

TOXICITY OF ASPEN WOOD LEACHATE TO AQUATIC LIFE: LABORATORY STUDIES

Trembling aspen (Populus tremuloides Michx.), a common hardwood tree throughout Canada, is being harvested at increasing rates for use in paper and building materials. Piles of aspen logs have been observed to produce a dark, watery, acutely toxic leachate. A laboratory study was undertaken to elucidate the nature, strength, and persistence of aspen leachate toxicity and the chemical composition of the leachate. Leaching from aspen chips in the laboratory was rapid, with 1% mass loss in the first 24 h. Another 2 weeks of immersion was necessary to remove all remaining leachable material (3% total). Fresh aspen leachate derived from a 1:9 wood-water mixture (35 d immersion) was characterized by amber color, low pH (4.0), extremely high BOD (>2,600 mg/L), and high conductivity (1140 μS/cm). The leachate was rich in phenols (30 mg/L), organic carbon (2,480 mg/L), and organic nitrogen (13 mg/L). Median acutely toxic concentrations of leachate were consistently 1 to 2% of full strength for trout and Daphnia. Inhibition of bacterial metabolism began at concentrations below 0.3%. Leachate was less toxic to plant life but inhibited algal growth at concentrations of 12 to 16%. Toxicity of aspen leachate persisted at the same level as in fresh leachate for more than 2 months unless artificial aeration was provided. Persistence was even greater at low temperature (5°C). Aged leachate underwent a transition marked by a rise in pH and dissolved oxygen concentration, a small decline in conductivity, and a color change, from amber to black. Toxicity declined abruptly when the supply of labile toxicants was exhausted, but it sometimes increased again from the products of microbial metabolism. Oxygen depletion, low pH, and phenolic compounds contribute to the toxicity of aspen leachate, but much of the toxic effect must be attributed to other, unidentified constituents.

Viscosity changes in orange juice after ultrafiltration and evaporation

Suspended solids, including cloud and pectin, were removed from orange juice using a hollow fiber ultrafiltration membrane (500 kDa). Orange juice serum had a clear amber color with no measurable turbidity. Regular and clarified orange juices were concentrated in a four stage, three effect TASTE (thermally accelerated short time evaporator) evaporator. The viscosity of the clarified juice was appreciably lower than that of regular juice, i.e. 15.55 mPa for serum and 164 mPa (at 100 s −1) for regular orange juice concentrate (65 °C, 66.5 ∘Brix). Flow behavior of orange juice serum tended to be Newtonian. Deviations from Arrhenius behavior were found for changes in viscosity of orange juice with temperature. Reduction in viscosity of orange juice increased heat transfer coefficients as reflected by the higher evaporation rates obtained for serum concentration.

Amber Disease Reduces Trypsin Activity in Midgut of Costeltyra zealandica (Coleoptera; Scarabaeidae) Larvae

Amber disease of the New Zealand grass grub Costelytra zealandica (Coleoptera: Scarabaeidae) is caused by ingestion of pADAP plasmid carrying isolates of Serratia entomophila or Serratia proteamaculans (Enterobacteriaceae) and causes infected larvae to cease feeding and clear their midgut to a pale amber colour where midgut serine protease activities are virtually eliminated. Using bacterial strains and mutants expressing combinations of the anti-feeding (afp) and gut clearance (sep) gene clusters from pADAP, we manipulated the disease phenotype and demonstrated directly the relationship between gene clusters, phenotype and loss of enzyme activity. Treatment with afp-expressing strains caused cessation of feeding without gut clearance where midgut protease activity was maintained at levels similar to that of healthy larvae. Treatment with strains expressing sep-genes caused gut clearance followed by a virtual elimination of trypsin and chymotrypsin titre in the midgut indicating both the loss of pre-existing enzyme from the lumen and a failure to replenish enzyme levels in this region by secretion from the epithelium. Monitoring of enzymatic activity through the alimentary tract during expression of disease showed that loss of serine protease activity in the midgut was matched by a surge of protease activity in the hindgut and frass pellets, indicating a flushing and elimination of the midgut contents. The blocking of enzyme secretion through amber disease appears to be selective as leucine aminopeptidase and α-amylase were still detected in the midgut of diseased larvae.

Optical absorption and Raman scattering spectra of Zn-S bonds in silicate glasses

The non-linear optical properties of microcrystalline semiconductor-doped glasses have received much attention in recent years [1]. In semiconductordoped glasses, the requirement for detailed information on particle size, size distributions and chemical compositions of microcrystalline semiconductors such as CdS or CdSl_xSex is inevitable to clarify the quantum confinement effect in semiconductors. Borrelli et al. [2] proposed from X-ray diffraction analyses that in some Corning sharp cut filter borositicate glasses containing ZnO, a solid solution Cd0.65Zn0.35S was formed during annealing. Very recently, Komatsu et al. [3] examined the Raman scattering spectra of CdS microcrystallites in Zn-free and Zn-added sodium silicate glasses and found that Cdl_,ZnxS solid solutions such as Cd08Zn0.2S were formed in the Zn-added glasses. Since the amount of soluble CdS in silicate glasses depends strongly on the amount of ZnO present in glasses [3], the role of zinc in silicate glasses is of much interest and it is important to clarify the effect of zinc on the state of sulphur in glasses and also in heat-treated samples. In this study we prepared sodium silicate glasses containing sulphur or ZnS and measured the optical absorption and Raman scattering spectra of the glasses and heat-treated samples in order to clarify the state of zinc and sulphur. In particular, we focus our attention on Zn-S bonds in glasses. The state of sulphur in the so-called sulphur-amber glasses has been studied extensively, and it is well known that a rich amber colour is produced by the combination of sulphur and iron oxide in sodium silicate glasses melted under strongly reducing conditions [4-6]. However, the study of Zn-S bonds in silicate glasses has not been reported and the presence of Zn-S bonds has not been confirmed experimentally. Silicate glasses with nominal compositions 55SiO2-30Na20-15CaO (reel%) containing various amounts of sulphur (0 .5 -3wt%) or ZnS (3-6 wt %) were prepared by using a conventional melt-quenching method. A platinum crucible was used, and the melting temperature and time were 1350 °C and 90 min, respectively. In order to release the internal stress in glasses the melts were poured onto an iron plate heated at around 300 °C. The glass transition, Tg, and crystallization, Tx, temperatures of a base glass 55SiO2-30Na20-15CaO were 488 °C and 607 °C, respectively. Optical absorption spectra were measured with a Hitachi U-3210 spectrometer. Raman scattering spectra at room temperature were measured by using an Ar ÷ laser (wavelength 514.5nm and laser power

An unexpected side reaction in the guaiacol assay for peroxidase

In routine guaiacol assays for thyroid peroxidase and lactoperoxidase employing a newly purchased bottle of guaiacol from Aldrich Chemical Co., we were surprised to find the formation of a blue color instead of the expected amber color classically associated with this assay. This was observed also with horseradish, myelo-, and cytochrome c peroxidase. The blue color ( A max ∼ 650 nm) was not formed with guaiacol reagents obtained from two other chemical companies, nor was it seen with a bottle of old Aldrich guaiacol that had been in use in the laboratory for more than 10 years. In the present investigation we provide evidence that formation of the blue color is closely associated with the presence of a low concentration of catechol (∼0.5 mol%) in the new Aldrich guaiacol reagent. Catechol itself, even in much higher concentration, is a very weak donor for peroxidase, forming a light pink color. The blue color in Aldrich new guaiacol is not formed to the exclusion of 470-nm-absorbing product(s). Formation of the latter is, however, inhibited, and use of Aldrich new guaiacol for assay leads to low values for peroxidase activity. Other dihydroxyphenols (resorcinol and hydroquinone) do not mimic the action of catechol in formation of the blue color. Resorcinol is a very potent inhibitor of peroxidation of guaiacol. Possible schemes are proposed for formation of the products that may be associated with the amber and blue colors.

Significance of Discoloration in Arenaceous Foraminifera

ABSTRACT Many Gulf Coast biostratigraphers have observed the discoloration of arenaceous Foraminifera in the subsurface Tertiary clastics of the Gulf of Mexico. This paper is a preliminary attempt to explain some possible reasons for the discoloration as well as to document formally the phenomenon. The initial interpretation was that discoloration is the result of increasing depth of burial and temperatures and caused by progressive and irreversible fixation of carbon derived from the catagenesis of the tectin of agglutinated foraminifers and organic matter from the surrounding sediments. However, pyrolysis analyses from several wells indicate the sediments are thermally immature. Discoloration in arenaceous Foraminifera ranges from amber to amber-brown, to brown, to gray, to black, and finally to bleached white. Organically poor sediments contain amber or normal sandy color arenaceous foraminifers, while organically rich sediments contain progressively darker color forms. The bleached opaque white forms, often also pitted, appear to be indicative of a paucity of organic matter in deeper and more heated sediments; it is speculated that the compound causing discoloration in blackened foraminifers may be driven out or volatilized at higher temperatures, giving rise to the bleached white color. Some genera of arenaceous foraminifers (i.e., those with labyrinthic internal structure) appear to be more sensitive to the color change than others. Minor color changes are also exhibited by some calcareous forms. Although the color changes are occurring in sediments immature for hydrocarbon generation, it is suggested that [1] heating is affecting organic matter so that some type of coloration is absorbed by the tectin from the organic matter of the surrounding sediment, [2] tectin proteins and polysaccharides may be far more temperature sensitive than plant materials and/or [3] discoloration indicates the passage of hydrocarbons through the sediments. A similar process has also been noted in several other microfossil groups but generally at higher temperatures and certainly over longer periods of time. It is very important to differentiate between the organically blackened specimens and those colored by the oxidation of diffuse pyrite, as most of the producing intervals of the Gulf of Mexico do contain some pyrite.

Muscle and plastic equivalent glass dosimeter for high-dose dosimetry

The alkali-silicate glass dosimeter is made up of 66.8% SiO2, 31.2% Li2O, 2% K2O. It is nearly colourless before irradiation and then takes on an amber colour with increasing doses of gamma-radiation. This colouration is represented by the appearance of broad absorption bands at 405 nm and 600 nm wavelengths. The change in absorbance is linear with the absorbed dose in the range 0.1–4.5 kGy, when measured at its 405 nm absorption band maximum. This glass dosimeter simulates low-z plastics and muscle tissue in terms of gamma-ray absorption properties over broad radiation spectra (0.1 MeV to 10 MeV).

AN INVESTIGATION OF THE ORIGIN OF THE COLOUR OF THE LYCURGUS CUP BY ANALYTICAL TRANSMISSION ELECTRON MICROSCOPY

The Lycurgus Cup (Figure 1) is an outstanding example of a late Roman cut glass cage cup. It is decorated in openwork with a frieze showing scenes of the myth of King Lycurgus. The cup, which is 165 mm high, was produced from a blown glass blank about 15 mm thick. The figures were cut and ground and are attached to the wall of the vessel by small glass bridges left by the cutter. It is dated to the fourth century A.D. on stylistic grounds, but is first recorded in 1845 and was acquired by the Rothschild family shortly after this date; its findspot is unknown (Harden and Toynbee 1959; Harden et al. 1987). In addition to the exceptional workmanship demonstrated by the cut decoration. the Lycurgus Cup is also noted for the unusual optical effects displayed by the glass. In transmitted light, the glass appears a deep wine-red, while in reflected light it is an opaque pea-green. Less than ten other examples of Roman glass showing this so-called ‘dichroic’ effect are known, but these are fragments. Furthermore, these other pieces show less intense colours than the Lycurgus Cup, or are brownish or amber in colour (Brill 1965; Harden et al. 1987). Chemical analyses of the glass of the cup were reported by Chirnside and Profitt ( 1 963 and 1965), Chirnside (1965) and Brill (1965). A composite of these analyses (mainly from Brill 1965) is given in Table 1. Brill also measured optical spectra of the glass and had a replica composition prepared. On the basis of these studies, Brill (1965) was able to conclude that the optical properties of the glass were caused by the presence of finely dispersed particles of gold, probably alloyed with silver. At the time of Brill’s study, it was necessary to infer the presence of the metallic particles by indirect means, since particles of the size postulated were then below the resolution limits for techniques such as scanning electron microscopy (SEM). However, modern transmission electron microscopy (TEM) can resolve and determine the structure of metal particles with diameters N 10 nm (e.g. Marks and Smith 1982). Compositional information on slightly larger particles is readily obtained by energy dispersive X-ray (EDX) spectrometry in the TEM. Thus analytical TEM offers a more positive and detailed characterization of the phases responsible for the dichroic properties of the glass of the Lycurgus Cup. In view of the interest generated by this unique piece of glass, it was decided to use about

Two crystal modifications of hexamethylcyclotristannatellurane

[(CH3)2SnTe]3, C6HI8Sn3Te3, Mr = 8291, Mo Ka radiation, h. = 0.71069 A, T = 293 K: (1) monoclinic, P21/c, a = 14-681 (2), b = 10.2775 (8), c =13.561(3) A, fl=112-087(12) ° , V =1896-0A 3, Z = 4, Dx = 2.905 Mg m-3, /.1, = 8.45 mm-1, F(000) = 1439.9, R=0.034 for 1968 observed data; (2) tetragonal, 141/a, a = 12-710 (3), c = 22.757 (4) A, V=3676.3A 3, Z = 8 , Dx=2996Mgm-3 , /z= 8-72 ram-l , F(000) = 2879.8, R = 0-024 for 1507 observed data. In each form the molecule adopts a twist-boat conformation which, in the case of the tetragonal modification, displays crystallographic twofold symmetry. Experimental. [(CH3)2SnTe]3 was obtained in petroleum solution by Soxhlet extraction of the crude reaction product (Blecher & Drfiger, 1979; Gay, Jones & Sharma, 1989). Evaporation of the solvent at room temperature yielded a sample consisting mainly of thin yellow-green sheets and a few thicker plates of amber colour. The solid state l l9Sn and lZSTe NMR spectra (Gay et al., 1989) displayed multiple resonances suggesting that more than one crystalline form was present. A plate selected from this sample for X-ray analysis was found to have crystallized in the space group P2~/c. A different yellow crystal modification was formed exclusively when a saturated petroleum solution of [(CH3)2SnTe]3 was cooled to 255 K, as confirmed by its solid state !19Sn and ~25Te NMR spectra (Gay et al., 1989). X-ray analysis showed these crystals to be tetragonal, space group I4~/a. Attempts to convert this phase to the monoclinic form by heating were unsuccessful. At 343 K the solid material appeared to fuse to give an apparently polymeric material of negligible solubility in petroleum ether. In either case the crystals became black upon exposure to air for several mintues. Crystals were mounted on Pyrex filaments with five-minute epoxy resin and were protected from air exposure by a thin coating of resin. Cell-parameter determination (25 reflections 15.1 _< 0_< 19.1 °, P21/c; 24 reflections 20.3 _ 0_ 25-7 °, I41/a) and data acquisition were performed using an Enraf-Nonius CAD-4F diffractometer with Mo Ka radiation and a graphite monochromator. The symmetry of the intensity-weighted reciprocal lattices and the systematic absences were determined using the diffractometer. Two standard intensities were measured every hour of acquisition time and showed no systematic variations. An empirical absorption correction (North, Phillips & Mathews, 1968) was applied to the data in the case of the I4~/a modification because the irregular shape of the crystal made measurement of crystal faces impracticable. The correction factors applied to the intensities ranged from 1.0 to 0.813. In the P2~/c case, an analytical absorption correction (de Meulenaer & Tompa, 1965) was made (transmission coefficients ranging from 0.614 to 0.248). Data reduction, including Lorentz and polarization corrections, was performed. In both cases the coordinates for the Te and Sn atoms were determined by direct methods (Main, Woolfson & Germain, 1971). The C-atom positions were revealed by electron density difference Fourier syntheses. H atoms were fixed at calculated positions with assigned isotropic temperature factors, basing the rotational conformation of each CH3 group upon the positions of the strongest peaks near the C atoms from a difference Fourier map. The final, full-matrix least-squares refinement, minimizing 0108-2701/89/111813-03503.00 © 1989 International Union of Crystallography 1814 HEXAMETHYLCYCLOTRISTANNATELLURANE Table 1. Data-acquisition and refinement details for two modifications of [(CH3)2SnTe]3

Chromatophoromas in a pine snake.

Iridophoroma and melanophoroma were diagnosed in an adult male pine snake. Light microscopic examination of irregularly thickened white and black portions of abnormal scales demonstrated two distinctive populations of pigment-containing cells. Pigment cells within abnormal-appearing white scales had needle-shaped granules that were dark amber in color while black portions were composed of pigment cells typical of melanophores, with dark black, round granules. Both populations of cells showed junctional activity, and clusters of both neoplastic pigment cell types were found in adjoining areas of the epidermis. By electron microscopy, the pigment cell with amber-colored granules contained reflecting platelet profiles typical of iridophores while pigment cells with dark round granules contained melanosomes. At a junctional area between abnormal white and black scales, mosaic chromatophores containing reflecting platelet profiles and melanosomes were observed. At 1 1/2 years following initial diagnosis, the snake died and neoplastic iridophores were found at multiple visceral sites; there was no evidence of metastases of melanophores to any organ. The two pigment cell tumors are believed to have developed from either stem cells destined to become iridophores and melanophores or from prexisting iridophores and melanophores in the dermis.

An improved immunofluorescence techniquefor the histological examination of blood vessel tissue

Autofluorescence of elastic fibres in blood vessel samples is a common interference with the specific fluorescence of FITC-conjugated antibodies. Counterstaining with eriochrome black T changed the yellow-green colour of elastic fibres to dark red, thus turning a disturbing feature into a useful reference background. A second counterstain, p-phenylenediamine, visualized cell nuclei as an amber colour. To demonstrate the improvement of this staining technique, cryosections from blood vessel samples, derived from control veins, arteries and experimental aneurysms of different ages (15 to 99 month old) in 5 sheep, were stained with antibodies against procollagen III, collagen type IV, laminin, and nidogen. The specific distribution of these connective tissue components could now be related to the location of the elastic fibres and the cells (cell nuclei).

反応性高周波スパッタ法によるＦｅ‐Ｂ‐Ｏ系薄膜の作製とその物性

Fe-B-Osystem thin films were fabricated by reactive rf sputtering from the composite targets of thin iron sheet and B2O3 tablets. The films are amber in color and have a high transmittance in the visible and the near infrared regions. Unfortunately, the exact identification of crystallographic structure of the films has not yet been succeeded. But judging from diffraction measurement, infrared absorption spectrum and SEM observation, the crystallographic structure of our samples seems to be close to polycrystalline ferric borate, FeBO3, whose c-axis is aligned perpendicular to the film plane. Saturation magnetization (4πMs=44G) is about one half of those reported for FeBO3 single crystal. Surprising-ly, our samples exhibit ferroelectricity at room temperature, despite FeBO3 by no means exhibits ferroelectricity. Saturation spontaneous polarization at room temperature (Ps=0.57μC/cm2) is more than twice that of Rochelle salt. Further we found that humidity plays an essential role for appearance of ferroelectricity. It is suggested that a hydrate formed by penetration of moisture into the films gives rise to ferroelectricity, since some zeolitic hydrates such as FeBO3·nH2O are known in ferric borates.

Quality Acceptance of Juices of Two Cultivars of Muscadine Grapes Mixed with Other Juices

Abstract Juices from 2 cultivars of muscadine grapes (Vitis rotundifolio Michx.), ‘Noble’ (dark-skinned) and ‘Carlos’ (bronze-skinned), were mixed with juices of ‘Concord’ and ‘Niagara’ grapes, cranberry or apple. ‘Noble’ juice, combined with ‘Concord’ juice, resulted in the highest quality among the dark mixtures prepared. Also, the mixtures retained most color and flavor during a 12 month storage period. ‘Carlos’ juice rated higher in quality when blended with the light-colored juices of apple and ‘Niagara’ than with the dark colored juice. The light amber color was stable during a 12 month storage period, and the flavor and overall acceptance of the mixture were rated higher than for the others.