Sapindaceous flowers from the Middle Eocene Princeton chert (Allenby Formation) of British Columbia, Canada

1990 ◽  
Vol 68 (9) ◽  
pp. 2025-2034 ◽  
Author(s):  
Diane M. Erwin ◽  
Ruth A. Stockey
Keyword(s):  
British Columbia ◽  
Key Words ◽  
Developmental Stages ◽  
Middle Eocene ◽  
Anther Wall

Seventeen small, staminate flowers, 3.0–4.5 mm long × 1.0–1.5 mm wide, representing two developmental stages of the same type of flower have been recovered from the Middle Eocene Princeton chert locality of British Columbia. Some specimens are immature buds with overlapping perianth parts enclosing the stamens; others represent mature flowers with an open perianth. Flowers are pedicellate with a small flat receptacle bearing a perianth of at least three sepals and up to four petals. Five specimens show a three- to four-lobed rudimentary pistil surrounded by an intrastaminal nectary disk. The 10 stamens are included or barely exserted with nonconnate filaments, 1.2–2.0 mm long, attached by a slender connective to large dithecal anthers up to about 0.9 mm long that open by longitudinal slits. The anther wall is represented by a palisadelike endothecium composed of cells that are thick-walled and radially elongated relative to the long axis of the anther. Abundant in situ pollen is semitectate–columellate, tricolporate, subprolate to prolate, and prominently striated with equatorially bridged colpi. This fossil combines flower and pollen characteristics similar to those of the Sapindaceae, resembling most closely the tribe Dodonaeeae. Key words: Sapindales, Dodonaeeae, Tertiary, permineralization, flowers, pollen.

A fossil flower with in situ Pistillipollenites from the Eocene of British Columbia

1988 ◽  
Vol 66 (2) ◽  
pp. 313-318 ◽  
Author(s):  
Ruth A. Stockey ◽  
Steven R. Manchester
Keyword(s):  
British Columbia ◽  
Convergent Evolution ◽  
Middle Eocene ◽  
New Taxon ◽  
Floral Structure ◽  
Ubisch Bodies ◽  
Spherical Hollow

A single actinomorphic flower has been found in the Horsefly Mine Top Section (Middle Eocene) of British Columbia. The flower, 2.1 cm in diameter, has six sepals, probably a superior ovary, and six stamens, one opposite each sepal. The pollen is morphologically identical with that of the dispersed grain of Pistillipollenites macgregorii Rouse. Grains, 22 μm in diameter, have numerous gemmae supported by columellae and a finer ornamentation of nanoverrucae. The grains are triporate with gemmae around apertures. Spherical hollow Ubisch bodies indicative of a secretory tapetum underlie remains of tapetal membranes. The floral structure of this new taxon, Pistillipollianthus wilsonii gen. et sp. nov., is distinctly different from the only other Pistillipollenites-producing flower described from the Eocene of Texas. The current study indicates that Pistillipollenites grains identified in sediments from the Cretaceous to the Eocene probably represent pollen from different angiosperm families, and it adds to the evidence that this type of gemmate grain may have evolved several times through convergent evolution.

An example of a peat flow near Prince Rupert, British Columbia

1985 ◽  
Vol 22 (2) ◽  
pp. 246-249 ◽  
Author(s):  
O. Hungr ◽  
S. G. Evans
Keyword(s):  
British Columbia ◽  
Moisture Content ◽  
Key Words ◽  
East Coast ◽  
High Potential ◽  
The World ◽  
Undrained Loading ◽  
Potential Mobility

Peat flows, bog flows, or bog bursts consist of a rapid downhill movement of masses of saturated peat. Although this process has been documented from peatlands in other parts of the world, the slope movement described here is the first to be reported from Canadian peatlands. The peat flow took place on the east coast of Kaien Island, near Prince Rupert, British Columbia, and was initiated by a slump in a peat spoil pile. It involved the sudden mobilization of a strip of in situ peat 210 m long and approximately 20 m wide. The peat was fibrous, rich in roots, and had a moisture content of approximately 240%. The flow demonstrates the high potential mobility of natural peat covers and the role of undrained loading in effecting movement of slopes as low as 5°. Key words: peat, flow slide, peat flow, northeast British Columbia.

Anatomically preserved plants from the Middle Eocene (Allenby Formation) of British Columbia

1977 ◽  
Vol 55 (14) ◽  
pp. 1984-1990 ◽  
Author(s):  
James F. Basinger ◽  
Gar W. Rothwell
Keyword(s):  
British Columbia ◽  
Plant Material ◽  
Developmental Stages ◽  
Middle Eocene ◽  
Vegetative Organs ◽  
Preliminary Examination ◽  
Early Tertiary ◽  
Plant Remains

Well preserved, permineralized plant material from the Middle Eocene, Allenby Formation of British Columbia provides the basis for this description of an extensive Tertiary flora. The flora comprises a diverse assemblage of abundant plant remains in a chert matrix which outcrops south of Princeton, B.C., Canada. Preliminary examination of this material reveals numerous fertile and vegetative organs of angiosperms, conifers, ferns, bryophytes, and fungi, most of which represent presently unknown taxa. Initial studies indicate that we are dealing with the most diverse Eocene permineralization flora ever discovered. Superb anatomical preservation, including developmental stages of various organs, characterize many of the taxa and promise to significantly increase our knowledge of early Tertiary plants.

Correlated Studies of Cellular Interactions Using TEM, Freeze Etching, and SEM

1974 ◽  
Vol 32 ◽  
pp. 320-321
Author(s):  
J. P. Revel
Keyword(s):  
Developmental Stages ◽  
Three Dimensional ◽  
Cell Movement ◽  
Cellular Interactions ◽  
Serial Sections ◽  
Cell Sheets ◽  
Freeze Etching ◽  
Early Developmental

Movement of individual cells or of cell sheets and complex patterns of folding play a prominent role in the early developmental stages of the embryo. Our understanding of these processes is based on three- dimensional reconstructions laboriously prepared from serial sections, and from autoradiographic and other studies. Many concepts have also evolved from extrapolation of investigations of cell movement carried out in vitro. The scanning electron microscope now allows us to examine some of these events in situ. It is possible to prepare dissections of embryos and even of tissues of adult animals which reveal existing relationships between various structures more readily than used to be possible vithout an SEM.

Efficiency of diagnosis and treatment non-invasive and microinvasive sgamous cell cervical cancer

2020 ◽  
pp. 71-74
Author(s):  
M.M. Melnyk ◽  
◽  
S.V. Nespradko ◽  
I.V. Goncharuk ◽  
M.V. Marchenko ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Key Words ◽  
National Cancer Institute ◽  
Reproductive Function ◽  
Diagnosis And Treatment ◽  
Non Invasive ◽  
Corpus Uteri ◽  
Complex Program ◽  
Early Cervical Cancer

The objective: analyse the effectiveness of diagnosis and treatment for early cervical cancer. Materials and methods. Analysed 107 cases of women’s disease on CIN ІІІ, cancer in situ, they were on treatment in National cancer institute and Kyiv dictrict cancer dispensary from 2010 till 2015 years. Results. Diagnosed percent relapse CIN ІІІ, cancer in situ contain 4.57% uninvasive and invasive form – 0.94%. Conclusion. According diagnostic CIN ІІ and CIN ІІІ is recommended to do treatment conization and dynamic dispensary observation. Are making complex program of infection HPV16, 18. In appering of margins resection some elements of tumor after wider conization by forms of cancer in situ. Many of expansive burns in cervical glands, in making of reproductive function, going disease (nodel leiomyoma of corpus uteri etc). In perspective is accept the notion of looking after and screening research of considering infection HPV16, 18 on CIN І, CIN ІІ. Key words: cervical cancer, сancer in situ, CIN І–ІІІ, diagnostic, treatment, conization.

scholarly journals Identification, Expression and Evolution of Short-Chain Dehydrogenases/Reductases in Nile Tilapia (Oreochromis niloticus)

2021 ◽  
Vol 22 (8) ◽  
pp. 4201
Author(s):  
Shuai Zhang ◽  
Lang Xie ◽  
Shuqing Zheng ◽  
Baoyue Lu ◽  
Wenjing Tao ◽  
...  
Keyword(s):  
Transcriptome Analysis ◽  
Tandem Duplication ◽  
Developmental Stages ◽  
Short Chain ◽  
Sexually Dimorphic ◽  
Physiological Processes ◽  
Genome Wide ◽  
Nile Tilapia Oreochromis Niloticus ◽  
Tandem Duplications

The short-chain dehydrogenases/reductases (SDR) superfamily is involved in multiple physiological processes. In this study, genome-wide identification and comprehensive analysis of SDR superfamily were carried out in 29 animal species based on the latest genome databases. Overall, the number of SDR genes in animals increased with whole genome duplication (WGD), suggesting the expansion of SDRs during evolution, especially in 3R-WGD and polyploidization of teleosts. Phylogenetic analysis indicated that vertebrates SDRs were clustered into five categories: classical, extended, undefined, atypical, and complex. Moreover, tandem duplication of hpgd-a, rdh8b and dhrs13 was observed in teleosts analyzed. Additionally, tandem duplications of dhrs11-a, dhrs7a, hsd11b1b, and cbr1-a were observed in all cichlids analyzed, and tandem duplication of rdh10-b was observed in tilapiines. Transcriptome analysis of adult fish revealed that 93 SDRs were expressed in more than one tissue and 5 in one tissue only. Transcriptome analysis of gonads from different developmental stages showed that expression of 17 SDRs were sexually dimorphic with 11 higher in ovary and 6 higher in testis. The sexually dimorphic expressions of these SDRs were confirmed by in situ hybridization (ISH) and qPCR, indicating their possible roles in steroidogenesis and gonadal differentiation. Taken together, the identification and the expression data obtained in this study contribute to a better understanding of SDR superfamily evolution and functions in teleosts.

Fossil Mosses from the Bisaccate Zone of the Mid-Eocene Allenby Formation, British Columbia

1974 ◽  
Vol 11 (3) ◽  
pp. 409-421 ◽  
Author(s):  
Marian Kuc
Keyword(s):  
British Columbia ◽  
Middle Eocene ◽  
Plant Tissues ◽  
Plant Remains ◽  
Lake Bottom ◽  
White Colour

New fossil taxa (Ditrichites fylesi, Muscites maycocki, M. ritchiei, Palaeohypnum jovet-asti and P. steerei); unnamed moss and moss-like fossils, detrital fragments of various plant tissues, and paleobotanical evidence of the bisaccate zone are described from the Middle Eocene Allenby Formation near Princeton, British Columbia. These remains occur in laminated, tuffaceous, silty and pyroclastic shale, deposited under lacustrine conditions.Detailed examination of the various laminae indicates that beds of white colour and composed of coarser silt grains are poor in fossils and could be related to periods of decreasing bioproduction; less silty and darker coloured beds are rich in macro- and microfossils and could be related to periods of extensive bioproduction. The rock features, lamination, and distribution of macrofossils indicate the slow and undisturbed accumulation of plant remains on a lake bottom.

Production of uredinia and telia by stalactiform blister rust in British Columbia

1993 ◽  
Vol 71 (3) ◽  
pp. 519-521 ◽  
Author(s):  
B. J. van der Kamp
Keyword(s):  
British Columbia ◽  
Life Cycle ◽  
Key Words ◽  
Alternate Host ◽  
Alternate Hosts ◽  
Blister Rust ◽  
Dry Areas ◽  
Do So

Records of uredinia and telia production on the alternate hosts of Cronartium coleosporioides in British Columbia and inoculation of Castilleja miniata with aeciospores collected from various locations showed that rust isolates from dry areas of the interior of British Columbia do not produce uredinia and may have lost the ability to do so. Collections from somewhat wetter areas produced uredinia or mixtures of uredinia and telia immediately following aeciospore inoculations, and field collections from such areas in June commonly had mixtures of uredinia and telia. Loss of the uredinial stage may be a response to climates that are often unsuitable for the spread or survival of the rust on the alternate host. Key words: stalactiform rust, uredinia, telia, rust life cycle.

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