Memoirs: The Structure and Development of Wax Glands of Pseudococcus Maritimus (Homoptera, Coccidae)

1937 ◽  
Vol s2-80 (317) ◽  
pp. 127-148
Author(s):  
PRISCILLA FREW POLLISTER
Keyword(s):  
Central Cell ◽  
Cell Multiplication ◽  
Histological Structure ◽  
Large Reservoir ◽  
The Third ◽  
Neck Cell ◽  
General Plan ◽  
Tormogen Cell ◽  
Peripheral Cells ◽  
Pseudococcus Maritimus

The females of Pseudococcus maritimus have three types of multicellular wax-glands, one with a triangular external pore, another opening through a long tube, and a third with a multilocular aperture. The first two are widely distributed on all surfaces of the adult. The third is restricted to the ventral surfaces of the last five segments. This multiloeular type is found only in the adult. The triangular glands are found at all stages and these structures progressively increase in number with each successive instar. The tubular type appears first in the second instar; the number is reduced in the third instar; and in the adult it is again increased to the largest number found at any stage. The three glands are all modifications of one general plan of histological structure. The glandular elements are sub-epidermal cells arranged in a ring of peripheral cells surrounding a single central cell. There are three peripheral cells in the triangular gland and ten in each of the others. The peripheral cells are uninucleate and contain vacuoles of secretory material. The central cell of the tubular and triangular glands has a large and two small nuclei and contains a large reservoir, from which a chitinized duct system leads to the gland-pore. The central cell of the multilocular gland is small and relatively undifferentiated. The author favours the view of Šulc that the wax is probably secreted by the peripheral cells, while the central cell secretes a substance that causes the wax filaments to adhere to form large cylinders. The glands are developed by cell-multiplication from the epidermis at the time when it is freed from the cuticula at the beginning of ecdysis. After the initial period of cell-multiplication the first differentiation is the development of the external pore within the neck-cell. Later in the development of multilocular glands it is believed the glandular cells grow through the neck-cell to establish the functional relationship with the pore. It is suggested that this is analogous to the relationship between tormogen cell and trichogen cell in the development of a spine.

XVIII. The Sources of Victor Hugo's Quatrevingt-Treize

PMLA ◽  
1924 ◽  
Vol 39 (2) ◽  
pp. 368-405
Author(s):  
Olin H. Moore
Keyword(s):  
The Third ◽  
General Plan ◽  
Principal Elements

Probably none of Victor Hugo's works has sources more complicated than Quatrevingt-treize. Accordingly, in order so far as possible to avoid confusion, the following paper has been divided into three parts, of graduated complexity. In the first part, a study is made of minor details in Quatrevingt-treize which Hugo borrowed from Blanc, Duchemin-Descepeaux, Lamartine, Garat, Du Rosel, the official Moniteur, as well as from other sources. The second part is devoted to the principal characters in Quatrevingt-treize, Marat, Robespierre, Danton; Cimourdain, Lantenac, Gauvain; l'Imânus and Michelle Fléchard. An attempt is made to discover the origins of the principal elements of these characters, and to demonstrate, to some extent, how these elements are welded together. The third part deals with the general plan of Quatrevingl-treize.

Development of Scolecolepis fuliginosa (Claparède)

1934 ◽  
Vol 19 (2) ◽  
pp. 633-654 ◽  
Author(s):  
J. H. Day
Keyword(s):  
Histological Structure ◽  
The Third ◽  
First Time ◽  
Young Worm

1. The development of Scolecolepis fuliginosa (Claparède) is described from the egg to the young worm for the first time.2. Comparison of reared larvæ with larvse from the plankton did not reveal any important difference.3. The eggs are pelagic, and are similar to those of Nerine.4. A description is given of the histological structure of a ciliated pit which arises in early larval existence and disappears at metamorphosis. The structure of the glandular region of the pygidium is also described.5. It is apparent that from the attainment of the fourth setiger onwards, the centre of differentiation is located in the third setiger, so that segmental structures arise first in this segment and then appear in the first and second setigers as well as in the succeeding ones.6. The larva of Scolecolepis has three pairs of eyes, the third pair disappearing in the young worm long after metamorphosis is otherwise complete.

scholarly journals First Report of Curvularia gladioli Causing a Leaf Spot on Gladiolus grandiflorus in Brazil

Plant Disease ◽  
2013 ◽  
Vol 97 (6) ◽  
pp. 847-847 ◽  
Author(s):  
D. P. Torres ◽  
M. A. Silva ◽  
D. B. Pinho ◽  
O. L. Pereira ◽  
G. Q. Furtado
Keyword(s):  
Leaf Spot ◽  
Central Cell ◽  
Post Inoculation ◽  
Intermediate Cell ◽  
Conidial Suspension ◽  
Single Spore ◽  
Internal Transcribed Spacer Region ◽  
First Report ◽  
The Third ◽  
Leaf Spots

Gladiolus (Iridaceae) is a popular bulbous plant grown worldwide as an ornamental garden plant or cut flower due to its attractive color, size, and flower shape. In April 2012, leaf spots were observed on plants of Gladiolus grandiflorus varieties T-704 and Amsterdam growing in a production area of cut flowers located in the city of Viçosa, Minas Gerais. The oval to round leaf spots were brown with a dark border surrounded by a halo of yellow tissue. Infected leaf samples were deposited in the herbarium at the Universidade Federal de Viçosa (VIC31897). A fungus was isolated from the leaf spots and a single-spore pure culture was initiated and grown on corn meal carrot agar (CCA) medium in petri dishes incubated at 25°C under a 12-h photoperiod for 4 weeks. A sporulating single-spore culture was deposited at the Coleção de Culturas de fungos fitopatogênicos “Prof. Maria Menezes” (UFRPE, Brazil) code CMM 4055. On CCA medium, the fungal isolate initially appeared white, becoming dark after 14 days. Thirty conidia and conidiophores were measured for identification to species. The septate, smooth to pale brown conidiophores were present singly or in groups. The simple, straight or flexuous conidiophores were 42.5 to 82.5 × 3.5 to 7.5 μm and some had a geniculate growth pattern. The majority of conidia were curved at the third (central) cell from the base, which was usually enlarged compared to the end cells. The cells at each end of the 3-distoseptate conidia were pale brown, the intermediate cell brown or dark brown, and the third (central) cell was often the darkest. The basal cell had a protuberant hilum. Conidia were smooth and 20.0 to 33.5 × 10 to 17.5 μm. These characteristics matched well with the description of Curvularia gladioli (1). To confirm this identification, DNA was extracted using a Wizard Genomic DNA Purification Kit and the internal transcribed spacer region (ITS) of rDNA was amplified using ITS1 and ITS4 primers and the partial 28S rDNA region using primers LR0R and LR5. The sequences were deposited in GenBank as accession nos. JX995106 and JX995107, respectively. The ITS sequence matched sequence AF071337, C. gladioli, with 100% identity. This pathogen was first identified as C. lunata, but based on the characteristic of the hilum, spore size, and pathogenicity testing, the fungus was renamed C. trifolii f. sp. gladioli (3). Due to the explicit curvature of the conidia at the third cell and molecular data, the fungus was reclassified as C. gladioli (1,2). To confirm Koch's postulates, 1-month-old healthy plants of G. grandiflorus var. T-704 and Amsterdam (five plants each) were inoculated with a conidial suspension (2 × 104 conidia mL–1) by spraying the foliage and then placed on a growth chamber at 25°C. The control plants were sprayed with distilled water. Symptoms were consistent with those initially observed and all plants developed leaf spots by 4 days post-inoculation. C. gladioli was consistently recovered from the symptomatic tissue and control plants remained symptomless. To our knowledge, this is the first report of C. gladioli causing leaf spot on G. grandiflorus in Brazil. Due to a lack of chemical fungicides for management of this pathogen, further studies to evaluate the susceptibility of the main varieties of gladiolus grown in Brazil to C. gladioli may be necessary. References: (1) G. H. Boerema and M. E. C. Hamers. Neth. J. Plant Pathol. 95:1, 1989. (2) D. S. Manamgoda et al. Fungal Divers. 56:131, 2012. (3) J. A. Parmelee. Mycologia 48:558, 1956.

Pathology of an arachnoid cyst

1979 ◽  
Vol 50 (2) ◽  
pp. 224-228 ◽  
Author(s):  
John Krawchenko ◽  
George H. Collins
Keyword(s):  
Arachnoid Cyst ◽  
Third Ventricle ◽  
Significant Degree ◽  
Histological Structure ◽  
Accidental Death ◽  
Arachnoid Membrane ◽  
Content Type ◽  
The Third ◽  
Interpeduncular Cistern ◽  
Fine Print

✓ Accidental death brought to autopsy a 19-year-old girl with an asymptomatic arachnoid cyst which had expanded from the region of the interpeduncular cistern so as to replace the third ventricle and extend into both lateral ventricles. Associated with this expansion was a significant degree of hydrocephalus, compression of the walls of the lateral ventricle, and obliteration of the normal structures of the floor of the third ventricle. The histological structure of the cyst wall and its relationship to the normal arachnoid are defined and found to consist of a reduplication of the normal arachnoid membrane resulting in a space within the arachnoid tissue. It is suspected but not proven that the cyst was congenital, resulting from an abnormality in development. Some suggestions are offered regarding the mechanism for its enlargement.

Structural investigation of the glandular trichomes of Salvia argentea

Biologia ◽  
2010 ◽  
Vol 65 (1) ◽  
Author(s):  
Pelin Baran ◽  
Canan Özdemir ◽  
Kamuran Aktaş
Keyword(s):  
Structural Investigation ◽  
Glandular Trichomes ◽  
Neck Cell ◽  
Capitate Trichomes ◽  
Peltate Trichomes ◽  
Peripheral Cells

AbstractThe morphology, anatomy and distribution of glandular trichomes on the aerial organs of Salvia argentea L. has been investigated. Two morphologically distinct types of glandular trichomes were determined. Capitate glandular trichomes forming a base 1–7 celled, a stalk 1–5 celled or no stalk and a head uni- or bicellular had various types. In capitate trichomes, the neck cell that has an important role especially for xeroformic plants, acting to prevent the backflow of secreted substance through the apoplast has been distinctively observed in the investigated species. The capitate trichomes were present abundantly on all aerial organs of S. argentea. Peltate glandular trichomes had a large secretory head forming 1–5, 8 central and 8–10, 12, 14 peripheral cells. Peltate trichomes are present on all aerial organs, except petiole, being the most abundant on calyx and corolla. Results were shown by tables and photographs.

The Zambezi Development Scheme: Cabora Bassa

1974 ◽  
Vol 4 (2) ◽  
pp. 47-54
Author(s):  
Wolf Radmann
Keyword(s):  
United States ◽  
The United States ◽  
Development Plan ◽  
The Third ◽  
General Plan ◽  
Development Scheme ◽  
Aswan Dam ◽  
The Government ◽  
The Impact ◽  
Zambezi Valley

The impact of African opposition to the Portuguese Zambezi Development Scheme and in particular to the construction of the Cabora Bassa hydro-electric dam in Mozambique was first felt in Europe in 1968 and reached its climax in 1971. It has influenced the thinking and the decisions of a great many individuals, groups, and organizations in the United States as well. In view of the wide publicity accorded various attempts in the United States and elsewhere to prevent any further support of Portugal's efforts to retain control over its colonies and develop them economically, one can assume that the controversy over Cabora Bassa is familiar to most people interested in African affairs. Nevertheless, more information is needed with respect to the facts and viewpoints surrounding the Cabora Bassa Dam project itself.According to Portuguese sources, planning for the development of the Zambezi valley began with the First Development Plan in 1953. In March 1957, the Overseas Ministry created the Missao de Fomento e Povoamento do Zambezi (M.F.P.Z.)—or the Zambezi Development Office, an organization to develop and to populate the Zambezi valley. The general plan for this development was presented to the government in 1966, and in November 1967 invitations for tenders to construct the Cabora Bassa Dam were issued. Offers were due in January 1968.The Third Development Plan for the Portuguese African territories covering the period from 1968 to 1973 provides for investments in Mozambique of about US $730.7 million. The costs for constructing the dam and the complete power scheme at Cabora Bassa are estimated at US $517.5 million. Portugal will absorb US $421 million of this amount and South Africa US $96.5 million. The ultimate production of energy is estimated to be twice that of the Aswan Dam. It will be surpassed in capacity only by the Churchill Falls Dam in Canada and by dams in the USSR at Bratsk and Krasnoyarsk. The Aswan Dam was built at a cost of more than US $1,000 million—a figure considerably higher than the estimate for the Cabora Bassa Dam.

scholarly journals Histological Structure of The Optic Tectum in The Fresh Water Turtle in The Clemmys caspica caspica (Gmelin, 1774)

2012 ◽  
Vol 36 (0A) ◽  
pp. 123-133
Author(s):  
Nahla Abid Al-Ritha
Keyword(s):  
Fresh Water ◽  
Optic Tectum ◽  
Histological Study ◽  
Histological Structure ◽  
The Third ◽  
Optic Fibers

A histological study was conducted to examine the structure of optic tectum in Clemmys caspica caspica. The results showed that the optic tectum consist of seven strata and the third stratum consists of three substrata, as follows: The stratum zonula (SZ), the stratum opticum (SO), the stratum griseum et fibrosum superficiale (SGFS) which consist of three substrata are a, b, c, the stratum griseum centrale (SGC), the stratum album centrale (SAC), the stratum griseum periventriculare (SGP), and the stratum album periventriculare (SAP). The stratum zonula (SZ) was the thinnest stratum in the optic tectum and its main thickness was (17-19) μm, while the stratum griseum et fibrosum superficiale (SGFS) was the thickest and its main thickness was (234-243) μm.The stratum opticum (SO), which represents the second stratum called the optic fibers tract, it was found that the optic fibers enter the optic tectum through this stratum while these fibers goout from optic tectum through the (SGP) which is the sixth stratum.The stratum griseum et fibrosum superficiale (SGFS) which represents the third stratum contain a large number of stallete and piriform multipolar neurons and fusiform neurons.

Progress report on 21-cm observations at low latitude between longitudes (l 11) 0° and 66°

1967 ◽  
Vol 31 ◽  
pp. 177-179
Author(s):  
W. W. Shane
Keyword(s):  
Preliminary Report ◽  
Progress Report ◽  
Galactic Centre ◽  
Low Latitude ◽  
The Third ◽  
Introductory Lecture ◽  
Centre Region

In the course of several 21-cm observing programmes being carried out by the Leiden Observatory with the 25-meter telescope at Dwingeloo, a fairly complete, though inhomogeneous, survey of the regionl11= 0° to 66° at low galactic latitudes is becoming available. The essential data on this survey are presented in Table 1. Oort (1967) has given a preliminary report on the first and third investigations. The third is discussed briefly by Kerr in his introductory lecture on the galactic centre region (Paper 42). Burton (1966) has published provisional results of the fifth investigation, and I have discussed the sixth in Paper 19. All of the observations listed in the table have been completed, but we plan to extend investigation 3 to a much finer grid of positions.

The orbit of Pluto over a long interval of time

1966 ◽  
Vol 25 ◽  
pp. 227-229 ◽  
Author(s):  
D. Brouwer
Keyword(s):  
Periodic Orbit ◽  
Numerical Integration ◽  
Restricted Problem ◽  
Three Dimensional ◽  
The Third ◽  
Circular Restricted Problem ◽  
Resonance Relation

The paper presents a summary of the results obtained by C. J. Cohen and E. C. Hubbard, who established by numerical integration that a resonance relation exists between the orbits of Neptune and Pluto. The problem may be explored further by approximating the motion of Pluto by that of a particle with negligible mass in the three-dimensional (circular) restricted problem. The mass of Pluto and the eccentricity of Neptune's orbit are ignored in this approximation. Significant features of the problem appear to be the presence of two critical arguments and the possibility that the orbit may be related to a periodic orbit of the third kind.

Monte Carlo Algorithms for Moments of Transition Arrays

1988 ◽  
Vol 102 ◽  
pp. 79-81
Author(s):  
A. Goldberg ◽  
S.D. Bloom
Keyword(s):  
Monte Carlo ◽  
State Vector ◽  
Basis Vector ◽  
Collective State ◽  
Dispersion Characteristics ◽  
Dipole Strength ◽  
The Third ◽  
Monte Carlo Algorithms ◽  
Third Moment ◽  
Very High

AbstractClosed expressions for the first, second, and (in some cases) the third moment of atomic transition arrays now exist. Recently a method has been developed for getting to very high moments (up to the 12th and beyond) in cases where a “collective” state-vector (i.e. a state-vector containing the entire electric dipole strength) can be created from each eigenstate in the parent configuration. Both of these approaches give exact results. Herein we describe astatistical(or Monte Carlo) approach which requires onlyonerepresentative state-vector |RV> for the entire parent manifold to get estimates of transition moments of high order. The representation is achieved through the random amplitudes associated with each basis vector making up |RV>. This also gives rise to the dispersion characterizing the method, which has been applied to a system (in the M shell) with≈250,000 lines where we have calculated up to the 5th moment. It turns out that the dispersion in the moments decreases with the size of the manifold, making its application to very big systems statistically advantageous. A discussion of the method and these dispersion characteristics will be presented.

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