Glossy Appearance Research Articles

Round-cell mutants of Salmonella typhimurium produced by transposition mutagenesis: Lethality of rodA and mre mutations

Thirty-three insertions of transposon Tn10 delta 16 delta 17 into genes involved in the control of rod cell shape were isolated in Salmonella typhimurium by the characteristic glossy appearance of colonies composed of spherical cells. Genetic tests demonstrated that 25 (76%) were insertions in the rodA gene, 7 (21%) were mre mutants, and 1 (3%) was a divD mutant. No insertion in the pbpA gene were found. Insertions in cell shape genes only appeared when strains displaying resistance to mecillinam (not caused by beta-lactamase production) were employed. Neither rodA nor mre insertions could be transduced to wild-type strains but they were normally accepted by mecillinam-resistant derivatives and by cya and crp mutants, which, unlike the corresponding Escherichia coli strains, did not display resistance to mecillinam. On the other hand, the divD insertion could be efficiently transduced to any strain. It is concluded that the rodA, mre, and divD genes are involved in the control of rod cell shape but, in addition, the RodA and Mre products perform some function(s) that is essential for wild-type cells but dispensable for some mecillinam-resistant strains, and for cya and crp mutants.

<i>Cabochonicus,</i> a new genus for species of gemmate megaspores previously referred to <i>Verrutriletes</i>

Abstract. Several species of Mesozoic megaspores that are sculptured with globular, often gemmate elements are sufficiently distinct from most verrucate forms to warrant their inclusion in a genus other than Verrutriletes. Cabochonicus is erected to accommodate them with C. (al. Verrutriletes) carbunculus as the type species. The form of the gemmae, which have a glossy appearance, has been the subject of past debate with one interpretation being that they are the manifestation of fungal attack rather than sculpture. Evidence from ultrastructural studies suggests, however, that they are exinal excrescences. The spores are assumed to be the products of heterosporous lycopods and the structure of the wall layers may indicate selaginellalean affinities. The plants are more likely to have been terrestrial than aquatic or semi-aquatic.

Effects of Induced Low‐Temperature Stress on Raw Peanuts

ABSTRACTPeanuts were exposed to low temperatures before they were dried to simulate temperature abuse. Samples were exposed to temperatures ranging from 0°C to −6°C. Visual examination of exposed samples revealed a glossy appearance around the edges and on the central surface of the cotyledons. A comparison of volatile profiles from exposed samples (0°C to −6°C) showed increased concentrations of acetaldehyde and ethanol with decreased temperatures. Conductivity was a measure of the electrolytes in the leachate from exposed samples and reflected the extent of membrane leakage. Concentrations of organic carbon and inorganic ions increased with decreased temperatures. Evidence of increased acetaldehyde and ethanol concentrations indicated anaerobic respiration was involved in quality deterioration of freeze damaged peanuts.

Assessment of epidermal atrophy in localized scleroderma (morphea).

The skin surface of scleroderma skin becomes glossy as a result of epidermal atrophy. In this study, the skin relief was studied in 12 patients with localized scleroderma (morphea). Measurements by a stylus method showed smoothening of the skin in all plaques studied (p less than 0.01). Ultrasound measurement showed increased skin thickness (p less than 0.01). There was no correlation between smoothening of the skin surface and increase in skin thickness, and no correlation to the duration of the plaques. It is concluded that glossy appearance of plaques of scleroderma is an early sign, which may be useful in the clinical diagnosis of scleroderma.

The glossy appearance of a black bird: Thermal effects

1. 1.Solar reflectivity of the plumage of a glossy black bird, the male of Phainopepla nitens, is strongly affected by angle of incidence. 2. 2.The absolute change in a bird's net heat flux associated with angular effects probably is minor compared to other avenues of heat gain. This suggests that conventional measurements of reflectivity at near-normal angles of incidence are adequate for most applications and implies that the glossy appearance of dark-coloured birds may serve primarily behavioural functions.

塩化ナトリウムおよび硝酸ナトリウム水溶液中におけるＳＵＳ４３０鋼の電解脱スケール

This study has been made as a part of studies of electrolytic descaling of iron and steel in neutral electrolytes. In this report the descaling conditions of annealed SUS 430 steel and tis behaviour in electrolytes of sodium chloride and sodium nitrate were experimentally investigated. Results obtained are given in the following: In NaCl electrolyte, no dissolution of the scales on the steel was found, but some parts of the metal substrate exposed to the electrolyte through some scale defects dissolved in the electrolyte. Therefore, layers of the scales were removed by means of separating from the base metal during the electrolytic descaling process. In NaNO3 electrolyte, layers of the scales were removed by the dissolution of a Cr-oxide of the scale during the electrolytic descaling process. In the NaCl solution, a large number of pits were formed by Cl- ions on the descaled parts of the surface of the steel with no glossy appearance, while, in the NaNO3 solution, less pits were formed on the descaled surface. The surface in the latter solution had a well descaled glossy appearence at high temperatures.

Wax synthesis in Brassica oleracea as modified by trichloroacetic acid and glossy mutations

Two different mutations in Brassica oleracea, gl 5 and gl 4 have been re-investigated using acetate-1- 14C labelling in an attempt to define more closely the nature of the genetic blocks to wax synthesis. It has been found that gl 5 is a mutation which blocks elongation in the Step C 28–C 30. The mutation gl 4 exhibits no elongation block and could be blocked in the decarboxylation Step C 30–C 29. 0·1 mM TCA supplied in the culture solution of cauliflower seedlings affected the leaf surface by producing a glossy appearance similar to that induced by gl 3 and gl 4. At this concentration growth was not inhibited and the appearance of the plants was normal except for the surface wax. The amount of surface wax produced was about 40% of that in untreated seedlings on a leaf area basis. Slight, but significant changes in wax composition were noted, mainly involving a reduction in C 30 acids and aldehydes, a slight reduction (33–29%) in alkane content, and a marked difference in chain length composition of the alkanes with C 27 increased relative to C 29. Over a range of concentrations from 0·1–1 mM, TCA inhibited incorporation of label from acetate-1- 14C into C 30 acids and aldehydes more than into C 28 at concentrations 0·4–0·8 mM while label tended to accumulate in C 24 and C 26 acids; thus elongation C 28–C 30 was especially sensitive to TCA. TCA also inhibited incorporation into primary alcohols and esters almost as much as into C 29 compounds. In spite of relatively specific effects on incorporation of label into longer chain lengths, the resulting block to C 30 synthesis is not sufficient to make much difference to the overall rate of C 29 synthesis. Both results of analysis of wax from whole plants and experiments with tissue slices in vitro indicated that the effect of TCA in reducing the glaucousness of the leaf surface is a combination of overall reduction of wax synthesis together with slight but significant changes in wax composition.

Some effects of emulsion polymerization conditions on molecular polydispersity and rheological properties of poly(methyl methacrylate)

AbstractEmulsion polymerization conditions of free‐radical‐polymerized poly(methyl methacrylate) have been examined in relation to the molecular weight and molecular polydispersity of the resulting polymers. In turn, molecular weight and molecular polydispersity have been related to the apparent viscosity and the appearance of the extrudate produced by an Instron capillary rheometer. The length of time for monomer addition to the polymerization medium was found to be a variable of primary concern in the emulsion polymerization. Continuous monomer addition (from 1 to 2 hr) resulted in a poly(methyl methacrylate) with a narrow distribution (∼2.0) and medium molecular weight (∼132 × 103). Both molecular weight and polydispersity were found to significantly affect apparent viscosity and extrudate appearance. Differences in the rheological parameters were most marked at the lowest shear rate run in this study. The poly(methyl methacrylate) samples with medium molecular weight and more narrow molecular polydispersity exhibited the best combination of low apparent viscosity and smooth glossy appearance.

Some observations on the growth of YIG under oxygen pressure by the “fluxed melt” technique

The effects of an oxygen pressure on YIG single crystals grown from PbF2 rich fluxes are: (a) larger crystals, (b) glossy appearance, (c) raised leading edges, and (d) more flux inclusions up to 2.2 kg cm−2 pressure after which they decrease in percentage to the normal values of air grown garnets.

Potato Virus M Found in Japan

A virus was isolated from apparently healthy plants of potato varieties, USDA seedling 41956 and Kintoki-imo. The virus was transmitted by sap, but not by aphids so far as the present study concerned. By sap inoculation, it produced ring-like local lesions on the inoculated leaves of Nicotiana debneyi, while it caused systemic infection without symptoms in tomato and egg plant. Other plants such as Solanum demissum, S. villosum, Chenopodium amaranticolor, C. capitatum, C. murale, and Gomphrena globosa were also susceptible to the virus. Several potato varieties also became infected systemically.The virus was inactivated in 10 minutes between 65 and 70°C, and between 2 and 3 days, at room temperature (ca. 20°C). Dilution end point was shown to lie between 1:5, 000 and 1:10, 000. In electron microscopy using direct negative staining method devised by Doi et al. (1965), elongated particles of about 650mμ were observed. The virus was identified with potato virus M (PVM), because of its similarity to the description of PVM by Bagnall et al. (1956) in host range, mode of transmission, symptomatology, physical properties, and particle morphology. Antisera against PVM and PVS (potato virus S) were prepared by intravenous injections of rabbits with partially purified virus preparations. The antiserum against PVM was shown to have a homologous titre of 1:256 in precipitation test, and to be applicable to slide flocculation test. Result of cross precipitation tests between PVM-antiserum and PVS, and vice versa, showed some serological relationship between PVM and PVS. In the potato varieties Norin No.1, Oojiro, and Kennebec, mild to severe symptoms were observed on field-grown plants, naturally infected with PVM. The characteristic symptoms associated with PVM were of veinal streak, glossy appearance of leaf surface, crinkling, and downward curling of leaflets. Percentages of infection by PVM in seed potatoes maintained by the Tsumagoi National Potato Foundation Seed Farm were 11% in Norin No.1, 50% in Oojiro, 14% in Kennebec, 31% in Danshaku-imo, and almost 100% in Saco, USDA seedling 41956, and Kintoki-imo variety, respectively. With an exception of Norin No.1, these varieties were often symptomless carriers of PVM under field conditions.

Studies on the Taxonomy and Distribution of Sphagnum V. A New Species of Sphagnum from Quebec

Sphagnum splendens, a nonfibrillose species related to S. recurvum var. mucronatum, is described as new from Quebec. In most species of Sphagnum the hyaline cells of branch leaves are fortified by ring-like (or sometimes spiral-like) fibril bands which run all the way around the lumen and which, in a stained cross section through a leaf, appear like a septum with a central opening (see, for instance, Fig. 34 and 37 in Maass, 1967a). Nonfibrillose species are rare and so far included only one North American representative, S. macrophyllum Bernh. (Maass, 1967b). It was therefore of interest to discover in the interior of Quebec another species of Sphagnum lacking fibrils. The latter is obviously related to S. recurvum P. Beauv. agg., especially var. mucronatum (Russ.) Warnst. sens. Paul (=S. fallax Klinggr. = S. apiculatum H. Lindb.). It is named S. splendens for its glossy appearance. Sphagnum splendens Maass, sp. nov. (Fig. 1-4) Cellulae hyalinae sine fibrillis. Foliae ramnulorum siccatae non undulatae, nitidae. Ceterum haec planta Sphagno recurvo var. mucronato similis. CANADA. QUEBEC: 50 mi. W of Chapais, Maass, 5 Jul. 1965 (HERB. MAASs-holotype). The new species differs from S. recurvum var. mucronatum by the lack of fibrils (compare Fig. 1-4 and 5-8), by more appressed leaves which are never wavy when dry and whose tips are only weakly bent outward near the end of branches, and by its glossy appearance. The pores on the concave face of leaves tend to be more elliptical (extending in transverse direction to the cells) when compared with those of S. recurvum var. mucronatum. The type was found in a shallow pool of an extremely poor fen where it grew intimately mixed with S. recurvum var. mucronatum, S. majus (Russ.) C. Jens. (= S. dusenii C. Jens. ex Russ.), and Cladopodiella fluitans (Nees) Buch. Possibly S. splendens belongs to a group of plants endemic to northern Quebec and adjacent territory. The glossy appearance of the moss may be due to the absence of fibrils, which would be expected to change the absorption and reflection properties of the leaf. It is significant that all species of Sphagnum lacking fibrils are glossy, and that the perichaetial leaves of all Sphagnum species where fibrils are poorly developed or missing are likewise glossy. The curvature of leaves may also be influenced by the fibrillosity of the hyaline cells. Thus, S. splendens could have arisen from S. recurvum var. 1 Issued as National Research Council paper No. 9549. I am grateful to Drs. H. A. Crum, V. Krajina, and W. B. Schofield for help in the preparation of this paper. Part IV of this series of papers has been submitted to Nova Hedwigia. 2 Atlantic Regional Laboratory, National Research Council, Halifax, Nova Scotia, Canada. This content downloaded from 207.46.13.159 on Sun, 23 Oct 2016 04:50:42 UTC All use subject to http://about.jstor.org/terms 194 THE BRYOLOGIST [Volume 70

The Status of Hylocomium splendens var. tenue

it as Hylocomium splendens var. tenue Sharp (1933). In the recent checklist of North American mosses (Crum, Steere & Anderson, 1965), we erroneously referred the name to the synonymy of H. splendens var. gracilius (Boul.) Husn. - an unimportant growth form of the species, somewhat smaller, more compact, and less obviously proliferous than usual, and quite unlike the variety tenue. The variety tenue scarcely resembles Hylocomium splendens in size or aspect. It is completely lacking in paraphyllia (Fig. 8-10), a conspicuous and essential feature of Hylocomium, and there is little or no differentiation of stem and branch leaves (Fig. 1) other than a gradation in size (Fig. 7). To be sure, the leaves are remarkably similar to those of the ultimate branches of Hylocomium splendens in shape (Fig. 3-5), areolation (Fig. 2), and dorsal papillosity (Fig. 10). In Hylocomium splendens, however, the leaves of the ultimate branches show some significant differences: they are more concave with the upper margins incurved, the lower margins are not recurved, and the spiculose papillae at the back of the leaf cells are scattered and few rather than consistently present. In trying to place this moss taxonomically, we were led to a consideration of Pterigynandrum for a number of reasons including a similar size, general appearance, leaf shape, apex, decurrencies, and margins (serrulate in the upper half, narrowly recurved below the middle) (Fig. 6), small and relatively few quadrate alar cells, and, above all, the dorsal papillae caused by thickened and projecting cell ends. The thin-walled, relatively elongate leaf cells and small papillae obscured an obvious relationship to Pterigynandrum and indeed made Dixon's suggestion of an affinity to Hylocomium almost inspirational. However, a detailed study of Pterigynandrum filiforme Hedw. in all its variations has led us to the conclusion that Hylocomium splendens var. tenue is a species of Pterigynandrum differing from P. fiiforme most strikingly in having somewhat longer, much thinner-walled cells with much smaller papillae at back. A lack of pseudoparaphyllia (few and different to demonstrate in P. filiforme), as well as less concave and less crowded leaves with a more glossy appearance associated with smaller leaf papillae, fewer quadrate alar cells, and longer costae, helps to differentiate the species. No axillary brood bodies, so characteristic of the many expressions of P. filiforme (Crum, 1953), were found.

The Manufacture of Coke from Illinois Coal

The cool of Western Illinois, owing to the great amount of impurities occurring with it, may, with a few exceptions, be considered unfit for the iron smelting furnace, as well as for all other purposes requiring a fuel free from sulphur, and leaving but a small percentage of ash when burned. This coal is bituminous and mined without difficulty; the nearly horizontal beds are easily reached by shafts; the layers are stratified, and seams of dull and glossy appearance alternate.