Morphological forms and polyploidy in Triglochin procea agg. in Victoria.

1981 ◽  
Vol 29 (6) ◽  
pp. 639 ◽  
Author(s):  
L Robb ◽  
PY Ladiges

A numerical analysis of intraspecific variation within the Triglochin procera aggregate in Victoria suggests four morphologically distinct forms. Cytological studies indicate the polyploid series 2n = 16, 32, 64, the counts corresponding to three of the morphological forms. The diploid. designated form A. is found in north-central Victoria. It has distinctively small fruits, with 4-6 carpels. The pericarp is membranous, and the seed testa brown, hard and three-ridged. Flowering scapes are reddish. in comparison with the green scapes of the other forms. The tetraploid, designated form B, found in Gippsland, has globose, smooth, untwisted fruits on very short pedicels and terete leaves and scapes. In common with form C, it has a constant carpel number of 6, fruit with a fleshy pericarp, and seed with a smooth, pale, soft testa. The octoploid; form C, is the most widely distributed and the most variable form, particularly with regard to leaf morphology and degree of twisting of the carpels. Leaves are generally fleshy and broad, but may be thinner and trailing in fast-flowing water. Fruits are large. The fourth morphological form; D, is also an octoploid, with fruits like form C, but it has thin trailing. submerged, conspicuously veined leaves which contrast with the robust. emergent leaves of the other forms. It is found in the fast-flowing streams of east Gippsland.

Taxonomy ◽  
2021 ◽  
Vol 1 (3) ◽  
pp. 192-209
Author(s):  
Ream I. Marzouk ◽  
Salama M. El-Darier ◽  
Sania A. Kamal ◽  
Iman H. Nour

Launaea is a polymorphic genus with inter- and intraspecific inconsistencies. The study aimed to revise the classification and identification of Launaea species in Egypt. The study also aimed to assess the inter- and intraspecific variation among taxa using macro- and micromorphological characters. Numerical analysis was carried out on 156 specimens, which were collected from 63 sites in Egypt. The results revealed that L. arabica, L. capitata, L. intybacea and L. spinosa were significantly (p-value < 2.2 × 10−16 ***) discriminated from the other species at a high dissimilarity level. Launaea acanthodes was correctly identified as Lactuca orientalis. The study supported the inclusion of L. intybacea, L. massauensis and L. nudicaulis within section Microrhynchus, the separation of L. angustifolia and L. arabica in two distinct species. Two biotypes of L. nudicaulis were morphologically differentiated. Launaea fragilis subsp. fragilis showed considerable plasticity and variability in various characters; therefore, L. tenuiloba was considered to be merely an ecotype of L. fragilis. Launaea mucronata comprises two subspecies; cassiniana and mucronata, differentiated by their pappus type, conspicuous secondary ribs of the inner achenes, and the number of spines on the polar area of pollen grains.


1988 ◽  
Vol 62 (03) ◽  
pp. 411-419 ◽  
Author(s):  
Colin W. Stearn

Stromatoporoids are the principal framebuilding organisms in the patch reef that is part of the reservoir of the Normandville field. The reef is 10 m thick and 1.5 km2in area and demonstrates that stromatoporoids retained their ability to build reefal edifices into Famennian time despite the biotic crisis at the close of Frasnian time. The fauna is dominated by labechiids but includes three non-labechiid species. The most abundant species isStylostroma sinense(Dong) butLabechia palliseriStearn is also common. Both these species are highly variable and are described in terms of multiple phases that occur in a single skeleton. The other species described areClathrostromacf.C. jukkenseYavorsky,Gerronostromasp. (a columnar species), andStromatoporasp. The fauna belongs in Famennian/Strunian assemblage 2 as defined by Stearn et al. (1988).


2014 ◽  
Vol 541-542 ◽  
pp. 658-662
Author(s):  
Jian Li ◽  
Yuan Chen ◽  
Yang Chun Yu ◽  
Zhu Xin Tian ◽  
Yu Huang

To study the velocity and pressure distribution of the oil film in a heavy hydrostatic thrust bearing, a mathematical model of the velocity is proposed and the finite volume method (FVM) has been used to simulate the flow field under different working conditions. Some pressure experiments were carried out and the results verified the correctness of the simulation. It is concluded that the pressure distribution varies small under different rotation speed when the surface load on the workbench is constant. But the velocity of the oil film is influenced greatly by the rotation speed. When the rotation speed of the workbench is as quick as enough, the velocity of the oil film on one radial side of the pad will be zero, that is to say the lubrication oil will be drained from the other three sides of the recess.


1975 ◽  
Vol 23 (1) ◽  
pp. 113 ◽  
Author(s):  
MJ Littlejohn ◽  
JD Roberts

Mating calls of the northern and southern call races of the L. tasmaniensis complex are described. Analysis of call structure along a transect across the main contact between these allopatric forms in north central Victoria indicates that there is a zone of intergradation between 90 and 135 km wide, about 215 km long and with a north-westerly orientation. The interaction is interpreted as a secondary contact in which there is hybrid or recombinant superiority along a subtle ecological gradient.


1994 ◽  
Vol 04 (01) ◽  
pp. 49-88 ◽  
Author(s):  
CHRISTINE BERNARDI ◽  
MARIE-CLAUDE PELISSIER

This paper deals with a linear Schrödinger type equation in a rectangular domain with mixed Dirichlet-Neumann boundary conditions. The well-posedness of the continuous problem is proved, then a discrete problem is defined by combining a Legendre type spectral method in the first direction and a leap-frog scheme in the other one. The numerical analysis of the discretization is performed and error estimates are given. Numerical tests are presented.


1975 ◽  
Vol 75 (3) ◽  
pp. 413-424
Author(s):  
L. F. Gibson

SUMMARYA study of the incidence of diphtheria in the State of Victoria, Australia, was carried out. Numerical analysis of the characteristics of 264 strains ofCorynebacterium diphtheriaeisolated between 1962 and 1971 placed them into 18 varieties plus six strains which were unique in their combination of reactions to the characteristics examined. During the 10-year period, some varieties appeared inter mittently and were recognized by certain defining characteristics but exhibited a gradual change in their antigenic structure. In contrast, when the outbreaks were examined over shorter periods of time, a number of varieties and single strains were found which differed greatly from each other yet possessed the same major serotype antigen. These findings are discussed in terms of a 'one-parent' concept in which the varieties and single strains represent phases of a common ancestor.By inspection and analysis of the characteristics of the strains, certain associations were apparent. For instance, a correlation was found between the antigenic structure of the organism and the colonial appearance on tellurite blood agar. Similarly, correlation was observed between bacteriophage type, diphthericin type and biochemical activity in that a strain which was highly active in one of the properties was also very active in the other two.


1968 ◽  
Vol 25 (5) ◽  
pp. 877-901 ◽  
Author(s):  
Wilfred Templeman

Three specimens of Halargyreus johnsonii taken on the southwestern and southeastern slopes of the Grand Bank in 1959 and 1964 are apparently the first records of this species and genus from the western Atlantic. These specimens are compared with the holotypes of H. johnsonii Günther and of H. brevipes Vaillant and with the syntypes of H. affinis Collett and also with specimens identified as H. affinis from the north-central and northeast Atlantic and with specimens of H. johnsonii from Madeira and New Zealand. These three nominal species are also compared. Is it concluded that for the present all North Atlantic specimens may be referred to H. johnsonii and that the other two species names should be considered as junior synonyms of H. johnsonii.The New Zealand specimens of Halargyreus, described by Günther (1887, Challenger Rept., 22(Zoology), p. 1–268) as H. johnsonii, have higher numbers for some meristic characters than Atlantic specimens of H. johnsonii but these differences are not too great to be possibly due to environmental differences. Pending the study of additional specimens in better condition, these New Zealand specimens are tentatively allowed to remain as H. johnsonii.


2021 ◽  
Vol 20 (1) ◽  
pp. 25-33
Author(s):  
Posma Sariguna Johnson Kennedy

This study aims to learn about the implementation of health policies dealing with malnutrition, as well as the factors that drive and hinder the application of these policies, in the Nusa Tenggara Timur (NTT) Province of Indonesia (East Nusa Tenggara, in English). The results show that the border regions, specifically the Kupang and Timor Tengah Utara (North Central Timor) Regencies, suffer the worst conditions and have the greatest need for priority attention. Areas with better conditions are the Alor and Malaka Regencies, which should be given second priority. The Belu Regency produces better results than the other regencies and should be given third priority. Some programs and health service improvements must be carried out, such as the development and empowerment of Human Resources in the health sector, and improvement of the facilities and infrastructure of Community Health Centers (Puskemas) with their networks.


1983 ◽  
Vol 29 (103) ◽  
pp. 374-382 ◽  
Author(s):  
J. Weertman ◽  
G. E. Birchfield

AbstractWalder recently analyzed the initial instability of water flow in a sheet under a glacier that is produced by greater heat production in the flowing water and thus the larger rate of ice melting where a perturbation has increased the water sheet thickness. We have looked at the problem from the other presumed final state. We assume that instabilities have finally caused all the water to flow in channels (R-channels) at the bed. We investigated whether these channels can collect enough of the water that is produced by the geothermal heat and the heat sliding to remain in existence. When a basal shear stress is present, the distance out to which a channel can collect water is not that much greater than the channel radius itself. It is concluded that it is not likely for the channel to be able to collect appreciable amounts of water that is produced at the bed. Hence despite the indication that an instability initially might grow in a water sheet, this instability either cannot develop to the point when the water flow is primarily in channels or else the water flow alternates cyclically between a state primarily of sheet flow and a state of channel flow. It would appear that the channels that do exist under a glacier have their primary origin in the melt water from the upper surface that pours down moulins and thus is already channelized by the time it reaches the bed.


Zootaxa ◽  
2006 ◽  
Vol 1116 (1) ◽  
pp. 29 ◽  
Author(s):  
FRANCISCO PROVENZANO ◽  
NADIA MILANI

A new species of suckermouth armored catfish, Cordylancistrus nephelion, is described from seven specimens collected in tributaries of the Tuy River in the Caribbean Sea basin of north-central Venezuela. Cordylancistrus nephelion can be distinguished from the other species assigned to its genus by its unique color pattern, the head and body being marked with irregular white spots. Cordylancistrus nephelion is the third species of the genus described from Venezuela: Cordylancistrus torbesensis (Schultz 1944) from the Mérida mountain range (Cordillera de Mérida), Orinoco River basin; C. perijae Pérez and Provenzano 1996 from Perijá mountain range (Sierra de Perijá), Maracaibo Lake basin; and now C. nephelion from the La Costa mountain range (Cordillera de La Costa). These three species inhabit isolated foothill rivers and have very restricted geographic distributions. The extreme alteration of the Tuy River basin by humans may threaten Cordylancistrus nephelion and the other fish species endemic to the basin with extinction. An artificial key for the species assigned to the genus Cordylancistrus is presented.


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