Depositional processes in the distal part of a large alluvial fan's feeder channel in Himalayan foothills, India

Most industrial and academic geologists are familiar with the beautiful red and orange cathodoluminescence colours produced by carbonate minerals in an optical microscope with a cold cathode electron gun attached. The cement stratigraphies interpreted from colour photographs have been widely used to determine the post depositional processes which have modified sedimentary rock textures.However to study quartzose materials high electron densities and kV's are necessary to stimulate sufficient emission. A scanning electron microscope with an optical collection system and monochromator provides an adequate tool and gives the advantage of providing secondary and backscattered electron imaging as well as elemental analysis and distribution mapping via standard EDS/WDS facilities.It has been known that the incorporation of many elements modify the characteristics of the CL emissions from geological materials. They do this by taking up positions between the valence and conduction band thus providing sites to assist in the recombination of electron hole pairs.

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Differentiation Processes of the Ocellar Retina of the Honeybee (Apis Mellifera L.)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100159692 ◽

1990 ◽

Vol 48 (3) ◽

pp. 430-431

Author(s):

Maria Anna Pabst

Keyword(s):

Apis Mellifera ◽

Distal Part ◽

Cell Layer ◽

Single Layer ◽

Photoreceptor Cells ◽

Distal Segment ◽

Compound Eyes ◽

Thin Sections ◽

Ultrastructural Studies ◽

Adult Worker

In addition to the compound eyes, honeybees have three dorsal ocelli on the vertex of the head. Each ocellus has about 800 elongated photoreceptor cells. They are paired and the distal segment of each pair bears densely packed microvilli forming together a platelike fused rhabdom. Beneath a common cuticular lens a single layer of corneagenous cells is present.Ultrastructural studies were made of the retina of praepupae, different pupal stages and adult worker bees by thin sections and freeze-etch preparations. In praepupae the ocellar anlage consists of a conical group of epidermal cells that differentiate to photoreceptor cells, glial cells and corneagenous cells. Some photoreceptor cells are already paired and show disarrayed microvilli with circularly ordered filaments inside. In ocelli of 2-day-old pupae, when a retinogenous and a lentinogenous cell layer can be clearly distinguished, cell membranes of the distal part of two photoreceptor cells begin to interdigitate with each other and so start to form the definitive microvilli. At the beginning the microvilli often occupy the whole width of the developing rhabdom (Fig. 1).

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Review for "Fine‐grained gravity flow deposits and their depositional processes: A case study from the Cretaceous Nenjiang Formation, Songliao Basin, NE China"

10.1002/gj.4017/v2/review2 ◽

2020 ◽

Keyword(s):

Songliao Basin ◽

Gravity Flow ◽

Fine Grained ◽

Depositional Processes

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18F-Deoxyglucose PET for the staging of oesophageal cancer

Nuklearmedizin ◽

10.1055/s-0038-1625303 ◽

2003 ◽

Vol 42 (03) ◽

pp. 90-93 ◽

Cited By ~ 9

Author(s):

N. Döbert ◽

O. Rieker ◽

W. Kneist ◽

St. Mose ◽

A. Teising ◽

...

Keyword(s):

Oesophageal Cancer ◽

Squamous Cell ◽

Distal Part ◽

Standard Uptake Value ◽

Squamous Cell Carcinomas ◽

Tumour Grading ◽

Positron Emission ◽

Group A ◽

The Mean ◽

Drop Outs

SummaryAim: Evaluation of the influence of histopathologic sub-types and grading of primaries of oesophageal cancer, relative to their size and location, on the uptake of 18F-deoxyglucose (FDG) as measured by positron emission tomography (PET). Methods: 50 consecutive patients were evaluated. There were four drop-outs due to previous surgical and/or chemotherapeutical treatments and thus in 46 patients (28 squamous cell carcinomas and 18 adenocarcinomas) a pretherapeutic PET evalution of the primary including a standard uptake value (SUV) was obtained. In 42 cases data on tumour grading were available also. Results: Squamous cell carcinomas (SCC) were in 7/13/8 cases located in the proximal, medial and distal part of the oesophagus, respectively the grading was Gx in 3, G 2 in 12, G2-3 in 7, and G3 in 6 cases. The SUVmax showed a mean of 6.5 ± 2.8 (range 1.7-13.5). Adenocarcinomas (ACA) were located in the medial oesophagus in two cases and otherwise in its distal parts. Grading was Gx in one, G2 in 4, G2-3 in 3, G3 in 3, G3-4 in 3, and G4 in one case. The mean SUVmax was 5.2 ± 3.2 (range 1-13.6) and this was not significantly different from the SCC. Concerning the tumour grading there was a slight, statistically not relevant trend towards higher SUVmax in more dedifferentiated cancer. Discussion: SCC and ACA of the oesophagus show no relevant differences in the FDG-uptake. While there was a significant variability of tumour uptake in the overall study group, a correlation of SUV and tumour grading was not found.

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Lithostratigraphy of the Kweekvlei Formation (Witteberg Group), Cape Supergroup

South African Journal of Geology ◽

10.25131/gssajg.120.3.421 ◽

2017 ◽

Vol 120 (3) ◽

pp. 421-432 ◽

Cited By ~ 2

Author(s):

C. Browning ◽

M. Reid

Keyword(s):

South Africa ◽

Transition Zone ◽

Distal Part ◽

Vascular Plant ◽

Trace Fossil ◽

Plant Debris ◽

Lower Carboniferous ◽

Fossil Assemblage ◽

Low Diversity ◽

Storm Wave

AbstractThe Lower Carboniferous, probably Tournaisian, Kweekvlei Formation is part of the Witteberg Group (Cape Supergroup) of South Africa. Together with the overlying Floriskraal Formation, it forms an upward-coarsening succession within the Lake Mentz Subgroup. Sedimentary features of the Kweekvlei Formation suggest deposition in a storm-wave dominated marine setting, within the storm-influenced, distal part of an offshore transition zone environment. This predominantly argillaceous formation preserves a low diversity trace fossil assemblage. Reworked vascular plant debris (including the problematic genus Praeramunculus sp.) and a shark spine have been reported for the Kweekvlei Formation. There are no known stratigraphic equivalents in South Africa.

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A New Species of Rhacophorus Genus (Amphibia: Anura: Rhacophoridae: Rhacophorinae) from Van Ban District, Lao Cai Province, Northern Vietnam

Russian Journal of Herpetology ◽

10.30906/1026-2296-2019-26-6-325-334 ◽

2019 ◽

Vol 26 (6) ◽

pp. 325-334

Author(s):

Ivan I. Kropachev ◽

Nikolai L. Orlov ◽

Hoa Thi Ninh ◽

Tao Thien Nguyen

Keyword(s):

New Species ◽

Distal Part ◽

Slender Body ◽

Northern Vietnam ◽

Lao Cai ◽

Lower Ratio ◽

A New Species ◽

Green Triangle ◽

Brown Color

We describe a new species of the Rhacophorus genus, which differs from all species known in Asia by the combination of characters. It strongly differs also from small and middle-sized species of Rhacophorus sensu lato: Rhacophorus calcaneus Smith, 1924, Leptomantis cyanopunctatus (Manthey et Steiof, 1998), Rhacophorus hoabinhensis Nguyen, Pham, Nguyen, Ninh et Ziegler, 2017, Rhacophorus hoanglienensis Orlov, Lathrop, Murphy et Ho, 2001, Zhangixalus jarujini (Matsui et Panha, 2006), Rhacophorus laoshan Mo, Jiang, Xie et Ohler, 2008, Rhacophorus pardalis Günther, 1858, Rhacophorus rhodopus Liu et Hu, 1960, Rhacophorus robertingeri Orlov, Poyarkov, Vassilieva, Ananjeva, Nguyen, Sang, and Geissler, 2012, Leptomantis robinsonii (Boulenger, 1903), Rhacophorus spelaeus Orlov, Gnophanxay, Phimminith, and Phomphoumy, 2010, Rhacophorus translineatus Wu, 1977, Rhacophorus turpes Smith, 1940, Rhacophorus vampyrus Rowley, Le, Thi, Stuart et Hoang, 2010, Rhacophorus viridimaculatus Ostroshabov, Orlov et Nguyen, 2013 by having brown color with two green dorsolateral stripes starting at the groin level and connecting through the distal part of eyelid with green triangle on the head, slender body and head, lower ratio HW/HL 0.86, lower HW/SVL 0.28 and lower ratio HL/SVL 0.32.

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