scholarly journals Morphological characterization of the gonads of bullfrog tadpoles (Lithobates catesbeianus)

2015 ◽  
Vol 32 (04) ◽  
pp. 245-252 ◽  
Author(s):  
G. Rizzi ◽  
E. Silva-Zacarin ◽  
C. Oliveira ◽  
M. Costa ◽  
R. Salla ◽  
...  
Keyword(s):  
Light Microscopy ◽  
Acridine Orange ◽  
Morphological Study ◽  
Gonadal Development ◽  
Morphological Characterization ◽  
Lithobates Catesbeianus ◽  
Secondary Spermatocyte ◽  
Gosner Stage

Abstract Introduction: This work describes various aspects of early gonadal development of female and male in pre-metamorphic tadpoles (Lithobates catesbeianus) at Gosner stage 25. Materials and Methods: Ovaries and testicles were prepared for routine light microscopy for morphological study and for acridine orange technique fluroescent microscopy for observation of RNA cytoplasm activity. Results: The results showed that female gonads at Gosner stage 25 predominated primary and secondary oogonias, as well as primary, secondary and tertiary oocytes. The developing testicle presented primary spermatogonia (I or A) and secondary spermatogonia (II or B), and as well as primary and secondary spermatocyte. All this cell phases were morphologically characterized and the cell sizes measured. In pre-metamorphic testes the somniferous duct are not developed and the vasa deferentia is opened. Conclusion: At this point, it was possible differentiate ovary from testes does not for the gonadal cells, but for the general anatomy of the organs, being the ovary a spheroid structure and the testicle an elongated tubule.

Fine Structure of Pollen Walls in Lychnis Alba and the Presence of Silicon

1973 ◽  
Vol 31 ◽  
pp. 470-471
Author(s):  
Richard E. Crang
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
Light Microscopy ◽  
Elemental Composition ◽  
Organic Compounds ◽  
Morphological Characterization ◽  
Flowering Plants ◽  
X Ray ◽  
Inorganic Composition

Acid resistant components of the pollen wall and tapetal membrane in flowering plants have long been known to be composed of sporopollenin—a highly resistant mixture of organic compounds. Recent light microscopy and cytochemical analyses have led to the recognition that additional organic compounds comprise a significant part of these anther structures. However, comparatively little consideration has been given to the inorganic composition of the pollen exine and the morphologically similar tapetal membrane. Electron microscopy allows the morphological characterization of components and, when coupled with energy dispersive x-ray analysis, offers the opportunity to characterize elemental composition.

Morphological Characterization of Mycobacteriophage R1

1974 ◽  
Vol 32 ◽  
pp. 254-255
Author(s):  
B. L. Soloff ◽  
T. A. Rado
Keyword(s):  
Carbon Source ◽  
Stationary Phase ◽  
Growth Phase ◽  
Minimal Medium ◽  
Morphological Characterization ◽  
Logarithmic Growth Phase ◽  
Complete Lysis ◽  
Lysogenic Culture ◽  
Logarithmic Growth

Mycobacteriophage R1 was originally isolated from a lysogenic culture of M. butyricum. The virus was propagated on a leucine-requiring derivative of M. smegmatis, 607 leu−, isolated by nitrosoguanidine mutagenesis of typestrain ATCC 607. Growth was accomplished in a minimal medium containing glycerol and glucose as carbon source and enriched by the addition of 80 μg/ ml L-leucine. Bacteria in early logarithmic growth phase were infected with virus at a multiplicity of 5, and incubated with aeration for 8 hours. The partially lysed suspension was diluted 1:10 in growth medium and incubated for a further 8 hours. This permitted stationary phase cells to re-enter logarithmic growth and resulted in complete lysis of the culture.

Characterization of submicrometer fluid Inclusions in minerals by Analytical/Transmission Electron Microscopy and electron diffraction

1990 ◽  
Vol 48 (4) ◽  
pp. 424-424
Author(s):  
George Guthrie ◽  
David Veblen
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Electron Microscope ◽  
Electron Diffraction ◽  
Light Microscopy ◽  
Fluid Inclusions ◽  
Energy Dispersive Spectrometer ◽  
Analytical Transmission Electron Microscopy ◽  
Transmission Electron

The nature of a geologic fluid can often be inferred from fluid-filled cavities (generally <100 μm in size) that are trapped during the growth of a mineral. A variety of techniques enables the fluids and daughter crystals (any solid precipitated from the trapped fluid) to be identified from cavities greater than a few micrometers. Many minerals, however, contain fluid inclusions smaller than a micrometer. Though inclusions this small are difficult or impossible to study by conventional techniques, they are ideally suited for study by analytical/ transmission electron microscopy (A/TEM) and electron diffraction. We have used this technique to study fluid inclusions and daughter crystals in diamond and feldspar.Inclusion-rich samples of diamond and feldspar were ion-thinned to electron transparency and examined with a Philips 420T electron microscope (120 keV) equipped with an EDAX beryllium-windowed energy dispersive spectrometer. Thin edges of the sample were perforated in areas that appeared in light microscopy to be populated densely with inclusions. In a few cases, the perforations were bound polygonal sides to which crystals (structurally and compositionally different from the host mineral) were attached (Figure 1).

Morphological Characterization of Rhinacanthus Species of Sri Lanka

Planta Medica ◽  
2010 ◽  
Vol 76 (05) ◽  
Author(s):  
APPR Amarasinghe ◽  
RP Karunagoda ◽  
DSA Wijesundara
Keyword(s):  
Sri Lanka ◽  
Morphological Characterization

Density and morphological characterization of bacteria in integrated and exclusive production systems

2020 ◽  
Vol 13 (11) ◽  
pp. 1
Author(s):  
A. R. B. Zanco ◽  
A. Ferreira ◽  
G. C. M. Berber ◽  
E. N. Gonzaga ◽  
D. C. C. Sabino
Keyword(s):  
Bacterial Community ◽  
Rainy Season ◽  
Production Systems ◽  
Cropping System ◽  
Morphological Characterization ◽  
Native Forest ◽  
Exclusive Production ◽  
Colony Forming Units

The different integrated production systems can directly interfere with its bacterial community. The present study aimed to assess density, bacterial diversity and the influence of dry and rainy season in different integrated and an exclusive production system. The fallow and a native forest area was assessed to. Samples were collected in 2012 March and September. The isolation were carried out into Petri dishes containing DYGS medium. The number of colony forming units (CFU) was counted after 48 hours and. The bacterial density ranged between 106 and 107 CFU g-1 soil. The crop system affected the dynamics of the bacterial community only in the rainy season. The rainy season showed greater density of total bacteria when compared to the dry period regardless of the cropping system. The dendrograms with 80 % similarity showed thirteen and fourteen groups in the rainy and dry seasons. Isolates with the capacity to solubilize phosphate in vitro were obtained from all areas in the two seasons, but this feature has been prevalent in bacteria isolated during the rainy season

Characterization of Antibacterial-Producing Endophytic Fungi of Syzygiumpolyanthum Leaves

2020 ◽  
Vol 20 (4) ◽  
pp. 448-454
Author(s):  
Rahmita Burhamzah ◽  
Gemini Alam ◽  
Herlina Rante
Keyword(s):  
Molecular Characterization ◽  
Endophytic Fungi ◽  
Morphological Characterization ◽  
Test Method ◽  
Analysis Method ◽  
Nitrogen Base ◽  
Rdna Genes ◽  
Antibacterial Screening ◽  
Planting Method

Background: Endophytic fungi live in plants’ tissue and can produce the same bioactive compounds as its host plant produces. Syzygiumpolyanthum leaves have known to be one of the antibacterial compound producers. Aim and Objective: This study aimed to characterize morphologically, microscopically, and molecularly the antibacterial-producing endophytic fungi of Syzygiumpolyanthum leaves. Methods: The isolation of endophytic fungi was done by fragment planting method on PDA medium. The antibacterial screening was performed using the antagonistic test as the first screening followed by the disc diffusion test method. The morphological characterization was based on isolate’s mycelia color, growth pattern, margin, and surface texture of the colony, while the microscopic characterization was based on its hyphae characteristics. The molecular characterization of the isolate was done by nitrogen base sequence analysis method on nucleotide constituent of ITS rDNA genes of the isolate. Results: The results found that isolate DF1 has antibacterial activity against E.coli, S.aureus, P.acne, and P.aeruginosa, with the greatest inhibition at 10% concentration of broth fermentation extract on S.aureus with a diameter of inhibition of 13.77 mm. Conclusion: Based on macroscopic, microscopic, and molecular characterization, DF1 isolate is similar to Ceriporialacerate.

scholarly journals Microscopic Image Segmentation and Morphological Characterization of Novel Chitosan/Silica Nanoparticle/Nisin Films Using Antimicrobial Technique for Blueberry Preservation

Membranes ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 303
Author(s):  
Rokayya Sami ◽  
Schahrazad Soltane ◽  
Mahmoud Helal
Keyword(s):  
Ph Value ◽  
Silica Nanoparticle ◽  
Morphological Characterization ◽  
Aerobic Bacteria ◽  
Nano Materials ◽  
Elongation At Break ◽  
Stable Suspension ◽  
Average Size ◽  
Material Ductility

In the current work, the characterization of novel chitosan/silica nanoparticle/nisin films with the addition of nisin as an antimicrobial technique for blueberry preservation during storage is investigated. Chitosan/Silica Nanoparticle/N (CH-SN-N) films presented a stable suspension as the surface loads (45.9 mV) and the distribution was considered broad (0.62). The result shows that the pH value was increased gradually with the addition of nisin to 4.12, while the turbidity was the highest at 0.39. The content of the insoluble matter and contact angle were the highest for the Chitosan/Silica Nanoparticle (CH-SN) film at 5.68%. The use of nano-materials in chitosan films decreased the material ductility, reduced the tensile strength and elongation-at-break of the membrane. The coated blueberries with Chitosan/Silica Nanoparticle/N films reported the lowest microbial contamination counts at 2.82 log CFU/g followed by Chitosan/Silica Nanoparticle at 3.73 and 3.58 log CFU/g for the aerobic bacteria, molds, and yeasts population, respectively. It was observed that (CH) film extracted 94 regions with an average size of 449.10, at the same time (CH-SN) film extracted 169 regions with an average size of 130.53. The (CH-SN-N) film presented the best result at 5.19%. It could be observed that the size of the total region of the fruit for the (CH) case was the smallest (1663 pixels), which implied that the fruit lost moisture content. As a conclusion, (CH-SN-N) film is recommended for blueberry preservation to prolong the shelf-life during storage.

scholarly journals Morphological characterization of the Apis mellifera drones in the Southern Urals

2020 ◽  
Vol 604 ◽  
pp. 012030
Author(s):  
N R Gazizova ◽  
A G Mannapov ◽  
V N Sattarov ◽  
V G Semenov ◽  
A I Skvortsov ◽  
...  
Keyword(s):  
Apis Mellifera ◽  
Southern Urals ◽  
Morphological Characterization ◽  
The Southern Urals
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