Coronal Scales Research Articles

A Morphological Study of Some Silene L. Species of Caryophyllaceae family in Iraq

The current works included morphological features study (vegetative and floral parts) for five species of the genus Silene L., S. ampullata, S. chlorifolia, S. colorata, S. conoidea and S. longipetala belong to the family Caryophyllaceae, samples were collected from various areas of northern Iraq. Confirmation in the description was on the most critical parts of the plant, including the shape of the leaves, length, and shape of the calyx tube and venation, the modification shapes of coronal scales petals and appendages, anther ornamentation and structures of pistils. Images enhanced the morphological characteristics under study. Information on the locations and dates of the collection was also confirmed.

Sileneophioglossa (Caryophyllaceae, Sileneae), a new species from southwest China.

Sileneophioglossa Huan C. Wang & Feng Yang, a new species of Caryophyllaceae, is here described and illustrated based on morphological and molecular evidence. The new species was found in Sichuan and Yunnan provinces, southwest China. Phylogenetic analysis based on ITS sequences showed this new species belongs to section Cucubaloides. Morphologically, it resembles S.phoenicodonta and S.viscidula, which were also found in the southwest China, but clearly differs from the latter two species by having 5-7 mm long calyces with sparsely hirtellous and short glandular hairs, white petals, linear limbs and lobes, and absent or oblong-linear coronal scales. A distribution map and a table with morphological diagnostic characters of new species and its closest relatives are provided, as well as a preliminary conservation assessment of S.ophioglossa under the IUCN criteria.

Morphological differentiation of bovine and equine hair for species’ identification in forensic veterinary investigations

In this paper a morphological differentiation tool of bovine and equine hair for their identification in forensic investigations is provided. 30 animals were used, fifteen adult bovines of the “Siboney de Cuba” breed and fifteen adult equines of the “Criolla” breed. These species are the most bred in Cuba and, at the same time, the most exposed to poaching and theft crimes. Hair from the cows was sampled from the dorsal region, the lateral region and the ventral region; on the other hand, the horses’ hair was sampled from the dorsal region of the body, of the mane and of the tail. The sampled areas, different for bovine and equine, have been chosen because they represent the different types of hairs present in the two species under examination. Getty et al. (2004), infact, reported that both in cattle and horses the length and thickness of the hair is reduced in a dorsal-ventral direction towards the abdomen, increasing its density. The samples were observed at an optical microscope with LCD display, at lens 4X, 10X, 40X and 100X, to determine cuticle scales, cortex, medulla and medullary index. As a result, it was noticed that both bovine and equine hair show a morphological and histomorphometric pattern based on the characteristics of the constitutive structures: cuticle scales, cortex and medulla. The bovines show a thin cuticle, coronal scales in mosaic with serrated edges and flattened irregularly, while in the equines it is thin and imbricated with irregular waves and intermediate spaces. The cortex in the bovines is thin crust dark brown and not pigmented; in the equines the cortex is dark brown, with light texture and isolated dark brown and black pigments. In both species, the white hairs do not show pigments. Through this investigation it can be noticed that one of the most important aspects in the species identification in forensic analysis is the medullary index, since it allows differentiation between animal and human species. In the bovine it is shown with an average of 0.60, while the equine shows an average medullary index of 0.49.

Hair histology as a tool for forensic identification of some domestic animal species.

Animal hair examination at a criminal scene may provide valuable information in forensic investigations. However, local reference databases for animal hair identification are rare. In the present study, we provide differential histological analysis of hair of some domestic animals in Upper Egypt. For this purpose, guard hair of large ruminants (buffalo, camel and cow), small ruminants (sheep and goat), equine (horse and donkey) and canine (dog and cat) were collected and comparative analysis was performed by light microscopy. Based on the hair cuticle scale pattern, type and diameter of the medulla, and the pigmentation, characteristic differential features of each animal species were identified. The cuticle scale pattern was imbricate in all tested animals except in donkey, in which coronal scales were identified. The cuticle scale margin type, shape and the distance in between were characteristic for each animal species. The hair medulla was continuous in most of the tested animal species with the exception of sheep, in which fragmental medulla was detected. The diameter of the hair medulla and the margins differ according to the animal species. Hair shaft pigmentation were not detected in all tested animals with the exception of camel and buffalo, in which granules and streak-like pigmentation were detected. In conclusion, the present study provides a first-step towards preparation of a complete local reference database for animal hair identification that can be used in forensic investigations.

A new species of Silene sect. Dipterosperma (Caryophyllaceae) from Malta

Silene melitensis, a new species beonging to the sect. Dipterosperma, is described and illustrated from Maltese Archipelago. This therophyte occurs along the calcareous rocky coast of Malta and Gozo islands, where it grows within the ephemeral meadows together with many halophytes. Based on its prostrate-ascending habit and succulent leaves, S. melitensis shows some morphological similarities with S. nummica and S. crassiuscula, both included in the S. colorata group. S. melitensis differs from S. nummica in having inflorescence more flowered, petals smaller, claw on the back pubescent in the midrib, capsule bigger, carpophore shorter and seed with undulate wings, while it differs from S. crassiuscula in having scapes branched at the base, calyx tomentose-hirsute and shorter, petal limb shorter, coronal scales shorter and undulate, ovary shorter and seed larger. An diagnostic key of the taxa belonging to the sect. Dicterosperma is provided.

Three X-ray flares near primary eclipse of the RS CVn binary XY UMa

We report on an archival X-ray observation of the eclipsing RS CVn binary XY UMa (Porb ≈ 0.48 d). In two Chandra ACIS observations spanning 200 ks and almost five orbital periods, three flares occurred. We find no evidence for eclipses in the X-ray flux. The flares took place around times of primary eclipse, with one flare occurring shortly (< 0.125 Porb) after a primary eclipse, and the other two happening shortly (< 0.05 Porb) before a primary eclipse. Two flares occurred within roughly one orbital period (Δα ≈ 1.024 Porb) of each other. We analyze the light curve and spectra of the system, and investigate coronal length scales during both quiescence and flares, as well as the timing of the flares. We explore the possibility that the flares are orbit-induced by introducing a small orbital eccentricity, which is quite challenging for this close binary.

Silene peloritana (Caryophyllaceae) a new species from Sicily

Silene peloritana is described and illustrated as a narrow endemic circumscribed to Mt. Scuderi, an isolated peak of the Peloritani range (NE Sicily). The new species, belonging to S. sect. Dipterosperma, is a small therophyte growing on cacuminal carbonatic stands. It is well differentiated from the other Sicilian species of this section for its small size, shorter lower internodes, bracts and calyx teeth, petal lobes obovate, coronal scales purplish, and anthers pinkish-violet. A key of the Sicilian taxa belonging to Silene sect. Dipterosperma is provided.

Hoya lithophytica sp. nov. (Apocynaceae: Marsdenieae), from western Thailand

A new species of Hoya R. Br., Hoya lithophytica Kidyoo, has been discovered in western Thailand. Here we provide a detailed description and illustrations of this newly revealed species. It was found only on the cliff faces of limestone mountains. The new species is closely related to H. wightii Hook. f. subsp. palniensis K. T. Matthew. However, Hoya lithophytica has lateral nerves at right angles to the midrib and obovate coronal scales, but H. wightii Hook. f. subsp. palniensis has lateral nerves at acute angles to the midrib and elliptic coronal scales.

The Heating of Cool‐Star Coronae: From Individual Loops to Global Flux‐Flux Scalings

We simulate surface field patterns for cool dwarf stars of widely different levels of activity and estimate the associated global coronal radiative losses. We find that the integrated X-ray brightness of coronae of cool stars is relatively insensitive to the patterns of their surface magnetic fields, and that the X-ray flux is determined almost entirely by the magnetic flux through the stellar surfaces. This reconciles potentially inconsistent findings in the literature for the heating of solar and stellar coronae: solar studies suggested that the heating flux density entering coronal loops scales as FH = 0Bβ/Lλ (for a magnetic flux density B at the base of a loop of length L, with β = 1.0 ± 0.3 and λ = 1.0 ± 0.5), whereas combined solar and stellar data suggested that the X-ray flux density FX from entire cool-star coronae depends only on the average magnetic flux density || through the stellar photospheres. We find that the above two scalings are compatible because loop lengths and base magnetic flux densities are essentially uncorrelated for the global coronal loop ensemble and because the average loop lengths differ much less from star to star for Sun-like stars of different activity than the average base field strengths. We also explore the scaling properties of the constant of proportionality 0 for stars of significantly different surface gravity.

Solar Energetic Particle Acceleration in Refracting Coronal Shock Waves

Gradual solar energetic particle (SEP) events are known to be correlated with coronal mass ejections (CMEs) and soft X-ray flares. The current paradigm of particle acceleration in these events attributes it to CME-driven shock waves in the solar corona and in interplanetary space. Even in small gradual SEP events related to CMEs with speeds in the (possibly submagnetosonic) range of 300-800 km s-1, shock waves at global coronal scales, as evidenced by associated metric type II radio bursts, are important. Recent observational evidence from soft X-ray imaging data supports models of coronal shock wave propagation in the solar atmosphere as freely propagating blast waves that refract toward the solar surface as they propagate away from the flare site. Based on these observations, we study a model of test-particle acceleration in such a global refracting coronal shock wave. Such shocks may also be generated by solar eruptions other than flares, e.g., slow CMEs. The geometry of the shock wave results in the observer in the interplanetary medium being magnetically connected with the downstream region of the shock wave. Thus, steady-state diffusive shock acceleration predicts that the energy spectrum of the escaping ions is a power law, as typically observed—a result that is not obtained naturally if the observer is connected to the upstream region of the shock wave. Using parameters of upstream turbulence obtained from models of a cyclotron-heated solar corona, we calculate typical timescales of diffusive proton acceleration and show them to be consistent with the maximum proton energies typically observed in small, gradual SEP events. Acceleration in refracting coronal shock waves may also provide a preacceleration mechanism for further acceleration in CME-driven shocks in large gradual SEP events.

Hybrid Solar Energetic Particle Events Observed on Board Soho

We summarize ERNE/SOHO observations of solar energetic particle events associated with impulsive soft X-ray flares and LASCO coronal mass ejections (CMEs). The new observational data support an idea that the >10 MeV proton acceleration may be initiated at different coronal sources, operating in the flaring active region and on the global coronal scale, in concert with CME development. However, the particle acceleration continues beyond the coronal scales and may culminate at the interplanetary CME well after the flare. We emphasize the importance of CME liftoff/aftermath processes in the solar corona and the possible role of seed particle re-acceleration, which may explain the existence of hybrid solar energetic particle events.

Lychnis Viscaria L. (Viscaria Vulgaris Bernh.)

Subgenus Viscaria. A tufted winter-green perennial herb. Roots of two types, white, dense fibrous below stock and longer, thick, white adventitious. Stock, woody and supporting short, erect branches, ending in mostly very short densely leafy nonflowering shoots but sometimes longer up to 50 mm, with leaves crowded on top of first node. The flowering stem is 15-60 cm, erect, hollow, dark green, becoming purple and viscid under the nodes, glabrous or slightly hairy above. Cauline leaves 50-130mm x 4-10mm, oblong to linear-lanceolate to linear-spathulate, acuminate, entire, with woolly margins at the base, otherwise glabrous, narrowing below into a long stalk-like base which widens to join the stem, becoming purple. The inflorescence is an interrupted spike-like panicle of axillary, opposite dichasia with 3-6 flowers per cyme, becoming increasingly dense towards the apex. Bracts 3-35mm long, broadly lanceolate, acuminate, glabrous, decussate, clasping around the stem. Flowers 3-50, corolla 15-20mm, pedicels 3-5 mm. Calyx 615 mm, cylindrical-clavate, membranous, purplish, glabrous, 10 -ribbed with short ovate teeth. Five petals bright purple-red, pink, rarely white, entire or emarginate, with two conspicuous coronal scales 2-4 mm long at the base, claw narrow. Styles 5. Stigmas 5, feathery. Fruit 8-11 mm long, capsule ovoid, bursting the calyx, 5-8 celled, opening by 5(-8) recurved teeth, borne on a gynophore at least half as long as the ripe capsule. Seeds 0.4-0.7mm, reniform, black, with acute tubercles, borne on cells in radially and concentrically orientated rows. Seed weight 0.074 + 0.0029 mg.

A new species of Periploca (Periplocaceae) from Bangladesh

RAHMAN, M. A. & WILCOCK, C. C, 1992. A new species of Periploca (Periplocaceae) from Bangladesh. A new species of Periploca is described from Bangladesh. This is the only representative of the genus occurring in the flora of Bangladesh. It resembles P. graeca but may be distinguished by having shorter peduncles, glabrous calyx lobes, hairy coronal scales, broader and horizontally spreading follicles.

A reconsideration of the generic circumscription of Heterostemma Wight &amp; Arn. (Asclepiadaceae) and a new species from India

Heterostemma Wight & Arn. (Asclepiadaceae) and a new species from India. Heterostemma vasudemni Swarupanandan & Mangaly, a new species belonging to Asclepiadaceae is described and illustrated. The discoid-urceoloate corolla and the staminal coronal scales with a ventral appendage show this species to be intermediate between the two genera Heterostemma and Oianthus. Basically, the concepts of the two genera differ only in a pair of characters which, in the light of the new species seem not to be particularly diagnostic. On this basis it is proposed to merge the two genera together, by reducing Oianthus as a section under Heterostemma. Consequently, three new combinations are proposed. Examination of recent collections extends the distribution of what was 0. decanense, earlier considered to be endemic to Maharashtra, further south to Kerala.

Interspecific hybrids between Brassica napus L. and B. oleracea L. developed by embryo culture

Interspecific hybrids between Brassica napus and B. oleracea are difficult to produce, and previous attempts to transfer economic characters from one species to the other have largely been unsuccessful. In these studies, oilseed rape cv. Tower (2n∶38) (B. napus) was crossed with broccoli and kale (2n∶18) (B. oleracea), and hybrid plants were developed from embryos in culture by either organogenesis or somatic embryogenesis. In rape × broccoli, F1 plants were regenerated from hybrid embryos and the plants produced viable selfed seeds. F5 plants (2n∶38) homozygous for white flower colour were selected for high oil content (47%) and Line 15; a selection from these plants produced fertile hybrids with rape, broccoli and kale without embryo culture. In reciprocal crosses between oilseed rape cv. Tower and an aphid resistant diploid kale, 28 and 56 chromosome F1 hybrid plants were regenerated from somatic embryos. The 56 chromosome plants were self-fertile and it was concluded from F2 segregation ratios that a single dominant gene controls resistance to cabbage aphid in kale. The 28 chromosome F1's were self-sterile, but these and the 56 chromosome F1's could be backcrossed to rape and kale. A cross between the F1 (2n∶56) and a forage rape resulted in the selection of a cabbage aphid (Brevicoryne brassicae L.) resistant line (Line 3). Both Line 15 and Line 3 can serve as bridges for gene interchange between B. campestris, B. napus and B. oleracea, which has not been possible hitherto. Hybridisations between rape and tetraploid kale produced F1 plants with 37 chromosomes. One F2 plant possessed coronal scales and the inheritance was shown to be controlled by a single recessive gene unlinked to petal colour.