scholarly journals Comparative Taxonomic Study of Launaea Cass. (Asteraceae, Cichorioideae) in Egypt

Taxonomy ◽  
2021 ◽  
Vol 1 (3) ◽  
pp. 192-209
Author(s):  
Ream I. Marzouk ◽  
Salama M. El-Darier ◽  
Sania A. Kamal ◽  
Iman H. Nour
Keyword(s):  
Numerical Analysis ◽  
Intraspecific Variation ◽  
Pollen Grains ◽  
Distinct Species ◽  
The Other ◽  
P Value ◽  
Taxonomic Study ◽  
Polar Area ◽  
Micromorphological Characters

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.

scholarly journals A numerical taxonomic study of the family Zygophyllaceae from Egypt

2012 ◽  
Vol 26 (1) ◽  
pp. 165-180 ◽  
Author(s):  
Kadry N. Abdel khalik
Keyword(s):  
Numerical Analysis ◽  
Systematic Study ◽  
Pollen Grains ◽  
Morphological Characters ◽  
Taxonomic Study ◽  
Peganum Harmala ◽  
Homogeneous Groups ◽  
Factor Loadings ◽  
The Family ◽  
Numerical Taxonomic Study

A systematic study of 29 taxa belonging to 7 genera of subfamilies Balanitoideae, Zygophylloideae, Peganoideae, Tribuloideae, Seetzenioideae and Tetradiclidoideae of Zygophyllaceae from Egypt was carried out by means of numerical analysis based on sixty-one morphological characters, including vegetative parts, pollen grains and seeds. On the basis of UPGMA clustering and PCO analysis, six main groups are recognized. Representatives of these groups are clustered together based on characters with high factor loadings in the PCO analysis. The results indicate that Zygophyllaceae are heterogeneous, including Peganum harmala which has been proposed to belong in a separate family. Zygophylloideae, Tribuloideae, Tetradiclidoideae and Seetzenioideae are the most homogeneous groups. Sections and groups in both Tribulus and Fagonia seem artificial.

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

1981 ◽  
Vol 29 (6) ◽  
pp. 639 ◽  
Author(s):  
L Robb ◽  
PY Ladiges
Keyword(s):  
Numerical Analysis ◽  
Intraspecific Variation ◽  
Leaf Morphology ◽  
The Other ◽  
Flowing Water ◽  
Morphological Form ◽  
North Central ◽  
Variable Form ◽  
Central Victoria ◽  
Seed Testa

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.

Status of Family Fissidentaceae in Gujarat

2016 ◽  
Vol 1 (1) ◽  
Author(s):  
D.G. Shah ◽  
D.N. Mehta ◽  
R.V. Gujar
Keyword(s):  
Distinct Species ◽  
The State ◽  
The Other ◽  
Land Plants ◽  
Reproductive Structures ◽  
The Family ◽  
The Status ◽  
Vegetative Characters ◽  
First Time ◽  
Different Parts

Bryophytes are the second largest group of land plants and are also known as the amphibians of the plant kingdom. 67 species of bryophytes have been reported from select locations across the state of Gujrat. The status of family fissidentaceae which is a large moss family is being presented in this paper. Globally the family consists of 10 genera but only one genus, Fissidens Hedw. has been collected from Gujarat. Fissidens is characterized by a unique leaf structure and shows the presence of three distinct lamina, the dorsal, the ventral and the vaginant lamina. A total of 8 species of Fissidens have been reported from the state based on vegetative characters as no sporophyte stages were collected earlier. Species reported from the neighboring states also showed the absence of sporophytes. The identification of different species was difficult due to substantial overlap in vegetative characters. Hence a detailed study on the diversity of members of Fissidentaceae in Gujarat was carried out between November 2013 and February 2015. In present study 8 distinct species of Fissidens have been collected from different parts of the state. Three species Fissidens splachnobryoides Broth., Fissidens zollingerii Mont. and Fissidens curvato-involutus Dixon. have been identified while the other five are still to be identified. Fissidens zollingerii Mont. and Fissidens xiphoides M. Fleisch., which have been reported as distinct species are actually synonyms according to TROPICOS database. The presence of sexual reproductive structures and sporophytes for several Fissidens species are also being reported for the first time from the state.

The Numerical Analysis of the Velocity and Pressure Distribution of the Oil Film in Heavy Hydrostatic Thrust Bearing

2014 ◽  
Vol 541-542 ◽  
pp. 658-662
Author(s):  
Jian Li ◽  
Yuan Chen ◽  
Yang Chun Yu ◽  
Zhu Xin Tian ◽  
Yu Huang
Keyword(s):  
Mathematical Model ◽  
Numerical Analysis ◽  
Pressure Distribution ◽  
Working Conditions ◽  
Thrust Bearing ◽  
Rotation Speed ◽  
The Other ◽  
Surface Load ◽  
Oil Film ◽  
Volume Method

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.

Aspidistra revoluta, a new species from limestone areas in Chongqing, China

Phytotaxa ◽  
2016 ◽  
Vol 257 (3) ◽  
pp. 280 ◽  
Author(s):  
Hao Zhou ◽  
Si-rong Yi ◽  
Qi Gao ◽  
Jie Huang ◽  
Yu-jing Wei
Keyword(s):  
New Species ◽  
Chromosome Number ◽  
Average Length ◽  
Chromosome Complement ◽  
Pollen Grains ◽  
The Other ◽  
Morphological Comparison ◽  
Chongqing Municipality ◽  
Karyotype Asymmetry ◽  
A New Species

Aspidistra revoluta (Asparagaceae) is described and illustrated as a new species from limestone areas in southern Chongqing Municipality, China. The new species can be distinguished from the other Aspidistra species by its unique umbrella-like pistil with large revolute stigma lobes that bent downwards and touch the base of the perigone. A detailed morphological comparison among A. revoluta, A. nanchuanensis and A. carnosa is provided. The pollen grains of A. revoluta are subspherical and inaperturate, with verrucous exine. The chromosome number is 2n = 38, and the karyotype is formulated as 2n = 22m + 6sm + 10st. The average length of chromosome complement is 4.50 μm, and the karyotype asymmetry indexes A1 and A2 are respectively 0.37±0.03 and 0.49±0.01.

SPECTRAL APPROXIMATION OF A SCHRÖDINGER TYPE EQUATION

1994 ◽  
Vol 04 (01) ◽  
pp. 49-88 ◽  
Author(s):  
CHRISTINE BERNARDI ◽  
MARIE-CLAUDE PELISSIER
Keyword(s):  
Numerical Analysis ◽  
Type Equation ◽  
Neumann Boundary ◽  
Rectangular Domain ◽  
The Other ◽  
Well Posedness ◽  
Discrete Problem ◽  
Spectral Approximation ◽  
Numerical Tests ◽  
Continuous Problem

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.

Campanula oreodoxa (Campanulaceae), a new critically endangered species from the Aladagh Mountains, NE Iran

Phytotaxa ◽  
2021 ◽  
Vol 521 (3) ◽  
pp. 193-202
Author(s):  
ALI ASGHAR ARJMANDI ◽  
HAMID EJTEHADI ◽  
FARSHID MEMARIANI ◽  
MOHAMMAD REZA JOHARCHI ◽  
MANSOUR MESDAGHI
Keyword(s):  
New Species ◽  
Pollen Grains ◽  
Critically Endangered ◽  
Conservation Value ◽  
Closely Related Species ◽  
Critically Endangered Species ◽  
Habitat Characterization ◽  
Alpine Species ◽  
Micromorphological Characters ◽  
Ne Iran

Campanula oreodoxa (Campanulaceae) is described and illustrated as a new sub-alpine species from North Khorassan province, Iran. The new species belongs to C. sect. Oreocodon based on dehiscence of the capsules with three middle pores at the base and absence of appendages between the calyx lobes. It is compared morphologically with the closely related species including C. hystricula and C. lourica. The micromorphological characters of seed coat and pollen grains of the new species are presented and compared with the chasmophytic allies in the area. Notes on distribution, habitat characterization, and the associated flora are provided. The new species is assessed as critically endangered (CR) and the conservation value of the habitats in the area is discussed.

Sintering Temperature Effect on Hardness of Self-Synthetisized Porcelain Made from Natural Sumatran Sand without Kaolin

2018 ◽  
Vol 782 ◽  
pp. 227-232
Author(s):  
Sianny Surya Putri Kurnia ◽  
Dede Taufik ◽  
Veni Takarini ◽  
Zulia Hasratiningsih
Keyword(s):  
Temperature Effect ◽  
Potassium Salt ◽  
Sintering Temperature ◽  
The Self ◽  
The Other ◽  
P Value ◽  
Natural Sand ◽  
Average Hardness ◽  
Different Temperatures ◽  
Statistic Result

Dental porcelain is one of the indirect restoration material with excellent aesthetic properties,on the other hand porcelain hardness frequently causing excessive wear of antagonist teeth. This study aiming to evaluate the effect of sintering temperature on the self-synthesized porcelain hardness. In this experiment, 25 porcelain samples were synthesized using Sumatran sand from Pangaribuan and Belitung regions, with the composition of 65 wt% Pangaribuan feldspar, 25 wt% Belitung silica and 10 wt% potassium salt. The samples were sintered in five different temperatures, which were 1110°C (A), 1120°C (B), 1130°C (C), 1140°C (D), and 1150°C (E). These samples were then invested on 5cm diameter resin each. The hardness was tested using Zwick Roell ZHμ Micro Vickers with 900 gram load for 15 seconds in 5 different indented areas for each sample. The result shows average hardness of 435.8 VHN (A), 461.0 VHN (B), 472.0 VHN (C), 487.6 VHN (D), and 528.7 VHN (E), which were increasing as the sintering temperature increased. Statistic result shows that sintering temperature significantly affected the hardness value of the porcelain (p value < 0.05). In conclusion sintering temperature affects the hardness of self-synthesized porcelain made from Sumatran natural sand without kaolin, although the average hardness of self-synthesized porcelain is still higher than average hardness of teeth enamel.

scholarly journals Numerical analysis of the characteristics ofCorynebacterium diphtheriaestrains isolated in Victoria from 1962 to 1971

1975 ◽  
Vol 75 (3) ◽  
pp. 413-424
Author(s):  
L. F. Gibson
Keyword(s):  
Numerical Analysis ◽  
Common Ancestor ◽  
Corynebacterium Diphtheriae ◽  
The State ◽  
The Other ◽  
Blood Agar ◽  
Antigenic Structure ◽  
Gradual Change ◽  
Biochemical Activity ◽  
Highly Active

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.

A new Species of Cicadulina, China (Homoptera, Jassidae) injurious to Maize in Tanganyika Territory

1936 ◽  
Vol 27 (2) ◽  
pp. 251-252 ◽  
Author(s):  
W. E. China
Keyword(s):  
New Species ◽  
Distinct Species ◽  
The Gambia ◽  
The Other ◽  
Colour Pattern ◽  
Streak Virus ◽  
Research Station ◽  
Two New Species ◽  
A New Species

The genus Cicadulina was established in 1926 (Bull. Ent. Res. 17, p. 43) to hold a new species, C. zeae, China, injurious to maize in Kenya Colony. Later (Bull. Ent. Res., 19, 1928, p. 66) it was shown that Balclutha mbila, Naude, recorded as transmitting the virus of streak disease of maize in Natal, also belonged to this genus, and two new species C. arachidis and C. similis were described from the Gambia, where they were reported as injurious to ground-nut and suspected of transmitting the virus of the rosette disease of that plant. Since that time Dr. H. H. Storey of the Amani Research Station has been investigating the possibility of transmission of the streak virus of maize by C. zeae. In attempting to breed strains capable of transmission of the disease certain crosses were made which showed conclusively that he was dealing with two distinct species. These species he was able to separate on the colour pattern of the abdomen. Dr. Storey has now sent to me material of both these species and a study of the genitalia corroborates his finding. One, of course, proved to be C. zeae, the other is new and I therefore propose to dedicate it to the discoverer.

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