Gonadal histology in the self-fertilizing hermaphroditic fish Rivulus marmoratus (Pisces, Cyprinodontidae)

1992 ◽  
Vol 70 (12) ◽  
pp. 2338-2347 ◽  
Author(s):  
Cristina G. Soto ◽  
John F. Leatherland ◽  
David L. G. Noakes
Keyword(s):  
Testicular Tissue ◽  
Gonadal Development ◽  
Rivulus Marmoratus ◽  
Gonadal Histology ◽  
Electron Microscopy Analysis ◽  
Microscopic Studies ◽  
Microscopy Analysis ◽  
Primary Male ◽  
Gonadal Structure

In nature, most individuals of Rivulus marmoratus are reportedly self-fertilizing hermaphrodites. A few rare individuals are males, but females have never been found in the field or laboratory. We describe the gonadal histology of this unique fish, mainly on the basis of light-microscopic studies with some elaboration by electron microscopy. Analysis of gonadal structure and the characterization of the stages of spermatogenesis and oogenesis allowed us to categorize functional gender and to construct the probable sequence of gonadal development in mature individuals. In our laboratory, some hermaphrodites underwent ovarian regression and testicular proliferation to become secondary males. One individual also developed as a primary male. However, the type of male could generally not be distinguished. Testicular tissue composed only a small portion (less than 10%) of the gonad of most hermaphrodites.

Synthesis and Characterization of Fibrous Bimetallic CuPt Nanoparticles

2016 ◽  
Vol 1 ◽  
Author(s):  
Elvy Rahmi
Keyword(s):  
Indium Tin Oxide ◽  
Lattice Mismatch ◽  
Fibrous Structure ◽  
Transfer Reactions ◽  
Individual Element ◽  
Key Factor ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis ◽  
Charge Transfer Reactions

<p>This paper reports a facile methode for the synthesis of fibrous bimetallic CuPt Nanoparticles (CuPt NPs) using the liquid phase deposition methods deposited directly on an indium-tin oxide (ITO) substrate. The electron microscopy analysis result shows that CuPt NPs, constructed by networked-nanorod of diameter ca. 3.5 nm and length approximately 5.5 to 6.5 nm, exhibits a quasi spherical morphology and fibrous structure with diameter approximately 196±98 nm. The differences of individual element miscibility and the effect of lattice-mismatch between Pt and Cu is the key factor for the formation of fibrous structure. XPS analysis indicated that the fibrous bimetallic CuPt NPs feature metallic properties with highly reactive surface. This may increase the charge-transfer reactions in catalytic, electrochemistry and sensors application.</p><p> </p>

New GroEL-like chaperonin of bacteriophage OBP Pseudomonas fluorescens suppresses thermal protein aggregation in an ATP-dependent manner

2016 ◽  
Vol 473 (15) ◽  
pp. 2383-2393 ◽  
Author(s):  
Pavel I. Semenyuk ◽  
Victor N. Orlov ◽  
Olga S. Sokolova ◽  
Lidia P. Kurochkina
Keyword(s):  
Pseudomonas Fluorescens ◽  
Functional Characterization ◽  
Dependent Manner ◽  
Double Ring ◽  
Protein Inactivation ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis ◽  
Ring Architecture

Recently, we discovered and studied the first virus-encoded chaperonin of bacteriophage EL Pseudomonas aeruginosa, gene product (gp) 146. In the present study, we performed bioinformatics analysis of currently predicted GroEL-like proteins encoded by phage genomes in comparison with cellular and mitochondrial chaperonins. Putative phage chaperonins share a low similarity and do not form a monophyletic group; nevertheless, they are closer to bacterial chaperonins in the phylogenetic tree. Experimental investigation of putative GroEL-like chaperonin proteins has been continued by physicochemical and functional characterization of gp246 encoded by the genome of Pseudomonas fluorescens bacteriophage OBP. Unlike the more usual double-ring architecture of chaperonins, including the EL gp146, the recombinant gp246 produced by Escherichia coli cells has been purified as a single heptameric ring. It possesses ATPase activity and does not require a co-chaperonin for its function. In vitro experiments demonstrated that gp246 is able to suppress the thermal protein inactivation and aggregation in an ATP-dependent manner, thus indicating chaperonin function. Single-particle electron microscopy analysis revealed the different conformational states of OBP chaperonin, depending on the bound nucleotide.

Production and characterization of titanium and iron oxide nano-sized thin films

2001 ◽  
Vol 16 (6) ◽  
pp. 1559-1564 ◽  
Author(s):  
E. Comini ◽  
G. Sberveglieri ◽  
M. Ferroni ◽  
V. Guidi ◽  
C. Frigeri ◽  
...  
Keyword(s):  
Thin Films ◽  
Iron Oxide ◽  
Gas Sensing ◽  
Iron Concentration ◽  
Radio Frequency Sputtering ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis ◽  
Reproducible Method

We present a simple and reproducible method to obtain TiO2 and Fe2O3 mixed-oxide thin films by reactive radio-frequency sputtering. The influence of iron concentration on the structural properties of the layers has been studied. Structural characterization, carried out by electron microscopy analysis, allowed one to correlate the inhibition of the grain growth of titania to the presence of iron oxide and to its segregation at grain boundaries. This behavior should be ascribed to a superficial-tension phenomenon. As a possible application of these thin films, we have investigated the gas-sensing properties toward CO, with particular focus on the role of Fe. The layers were capable to sense CO down to the level requested for environmental monitoring.

scholarly journals Power Generation: Feedstock for High-Value Sulfate Minerals

Minerals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 188
Author(s):  
Lucian C. Staicu ◽  
Tomasz Bajda ◽  
Lukasz Drewniak ◽  
Laurent Charlet
Keyword(s):  
Metal Removal ◽  
Cost Benefit Analysis ◽  
Cost Benefit ◽  
Raw Material ◽  
Flue Gas Desulfurization ◽  
X Ray Diffraction ◽  
Electron Microscopy Analysis ◽  
One Step ◽  
Microscopy Analysis

Coal-fired power facilities generate a polymetallic effluent (Flue Gas Desulfurization—FGD) rich in sulfate. FGD effluents may be considered an important secondary resource. This paper investigates the recovery of sulfate as barite (BaSO4), a mineral with high commercial value and a critical raw material. Using equimolar BaCl2, >99% desulfurization of an FGD effluent produced by a coal-fired power plant operating in central Poland was achieved, yielding up to 16.5 kg high purity barite m−3. The recovered barite was characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric (TGA), scanning electron microscopy analysis (SEM), surface properties (PZC), density, and chemical stability (TCLP), and was compared with a commercial reference material. Barite recovery also led to the reduction in concentration of Al (86%), Cu (52%), K (69%), Mo (62%), Se (40%), Sr (91%), and U (75%) initially present in the FGD effluent. TCLP results indicate the entrapment and the stabilization of ~70% Se and ~90% Al in the barite structure. Based on this dataset, an in-depth characterization of the recovered barite is presented, and the removal mechanism of the elements is discussed. The study also provides a preliminary cost benefit analysis of the process. To our best knowledge, this is the first work showing barite recovery and metal removal from FGD effluents using a one-step process.

SYNTHESIS AND CHARACTERIZATION OF HG-BASED SUPERCONDUCTING THIN FILMS PRODUCED STARTING FROM LASER-DEPOSITED PRECURSORS

2000 ◽  
Vol 14 (25n27) ◽  
pp. 2731-2736 ◽  
Author(s):  
M. BINDI ◽  
F. FUSO ◽  
N. PUCCINI ◽  
E. ARIMONDO ◽  
A. TAMPIERI ◽  
...  
Keyword(s):  
Thin Films ◽  
Laser Deposition ◽  
Precursor Film ◽  
Superconducting Thin Films ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electron Microscopy Analysis ◽  
Zero Resistance ◽  
Microscopy Analysis

Correctly c-axis oriented HgBa 2 CaCu 2 O 6+δ thin films have been produced on (100) MgO single crystal substrates and characterized. Pulsed laser deposition has been exploited to deposit Hg-free Re-doped precursor which then underwent synthesis in evacuated and sealed quartz tubes. X-ray diffraction pattern of the precursor target shows the expected composition of oxides. Scanning electron microscopy analysis have been performed on the surface of the precursor film. Hg-1212 films have been analyzed by θ-2θ Bragg-Brentano X-ray diffractometry. The patterns show little contributions in composition of Hg-1223 phase. The films exhibit a transition temperature >120 K with zero-resistance at around 115 K.

scholarly journals Further Characterization of Equine Foamy Virus Reveals Unusual Features among the Foamy Viruses

2002 ◽  
Vol 76 (14) ◽  
pp. 7220-7227 ◽  
Author(s):  
Charles-Henri Lecellier ◽  
Manuel Neves ◽  
Marie-Lou Giron ◽  
Joelle Tobaly-Tapiero ◽  
Ali Saïb
Keyword(s):  
Equine Infectious Anemia Virus ◽  
Foamy Virus ◽  
Nucleotide Sequence Analysis ◽  
Donor And Acceptor ◽  
Foamy Viruses ◽  
Electron Microscopy Analysis ◽  
Equine Infectious Anemia ◽  
Microscopy Analysis ◽  
Anemia Virus

ABSTRACT Foamy viruses (FVs) are nonpathogenic, widely spread complex retroviruses which have been isolated in nonhuman primates, cattle, cats, and more recently in horses. The equine foamy virus (EFV) was isolated from healthy horses and was characterized by molecular cloning and nucleotide sequence analysis. Here, to further characterize this new FV isolate, the location of the transcriptional cap and poly(A) addition sites as well as the main splice donor and acceptor sites were determined, demonstrating the existence of the specific subgenomic pol mRNA, one specific feature of FVs. Moreover, similar to what has been described for the human foamy virus (HFV), the prototype of FVs, a replication-defective EFV genome was identified during persistent infection. At the protein level, the use of specific antibodies allowed us to determine the size and the subcellular localization of EFV Gag, Env, and Tas, the viral transactivators. While EFV Gag was detected in both the cytoplasm and the nucleus, EFV Env mainly localized in the Golgi complex, in contrast to HFV Env, which is sequestered in the endoplasmic reticulum. In addition, electron microscopy analysis demonstrated that EFV budding occurs at the plasma membrane and not intracellularly, as is the case for primate FVs. Interestingly, EFV Tas was detected both in the nucleus and the cytoplasm of Tas-transfected cells, in contrast to the strict nuclear localization of other FV Tas but similar to the equine infectious anemia virus Tat gene product. Taken together, our results reveal that this new FV isolate exhibits remarkable features among FVs, bringing new insights into the biology of these unconventional retroviruses.

scholarly journals Molecular, Ultrastructural, and Biological Characterization of Pennsylvania Isolates of Plum pox virus

2011 ◽  
Vol 101 (5) ◽  
pp. 627-636 ◽  
Author(s):  
William L. Schneider ◽  
Vernon D. Damsteegt ◽  
Fred E. Gildow ◽  
Andrew L. Stone ◽  
Diana J. Sherman ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Host Range ◽  
The United States ◽  
Plum Pox Virus ◽  
Biological Characterization ◽  
Multiple Introductions ◽  
Aphis Spiraecola ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis

Plum pox virus (PPV) was identified in Pennsylvania in 1999. The outbreak was limited to a four-county region in southern Pennsylvania. Initial serological and molecular characterization indicated that the isolates in Pennsylvania belong to the D strain of PPV. The Pennsylvania isolates were characterized by sequence analysis, electron microscopy, host range, and vector transmission to determine how these isolates related to their previously studied European counterparts. Genetically, Pennsylvania (PPV-Penn) isolates were more closely related to each other than to any other PPV-D strains, and isolates from the United States, Canada, and Chile were more closely related to each other than to European isolates. The PPV-Penn isolates exist as two clades, suggesting the possibility of multiple introductions. Electron microscopy analysis of PPV-Penn isolates, including cytopathological studies, indicated that the virions were similar to other Potyvirus spp. PPV-Penn isolates had a herbaceous host range similar to that of European D isolates. There were distinct differences in the transmission efficiencies of the two PPV-Penn isolates using Myzus persicae and Aphis spiraecola as vectors; however, both PPV-Penn isolates were transmitted by M. persicae more efficiently than a European D isolate but less efficiently than a European M isolate.

scholarly journals Synthesis and mechanical characterization of a non-woven nanofiber by the electrospinning technique

DYNA ◽  
2019 ◽  
Vol 86 (209) ◽  
pp. 64-72
Author(s):  
Edwin Edgardo Espinel Blanco ◽  
Nelson Escobar-Mora ◽  
Lina Marcela Hoyos-Palacio ◽  
Martin Fabián Sarmiento-Gaviria
Keyword(s):  
Electron Microscopy ◽  
Mechanical Characterization ◽  
Average Diameter ◽  
Electrospinning Technique ◽  
Acid Ratio ◽  
Nanostructured Polymer ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis ◽  
Scanning Electron

A non-woven nanofiber or polymeric cover is synthesized with nylon-6 as the base polymeric material. Different acid relationships (formic/acetic) were tested in the electrospinning equipment, until defining by macroscopic observations and SEM Scanning Electron Microscopy analysis the adequate acid ratio 3:2 and the average diameter of the nanofibers in 350nm, defining the parameters to operate the electrospinning. According to ASTM D 882 standard, the Tensile Strength was calculated for stresses applied horizontally and vertically to the direction of the nanofibers. With the standards ASTM D 7490 and ASTM G-15 the wettability was determined by measuring the contact angle, finding that it has hydrophilic properties with high wettability, adhesiveness and surface energy. Nanostructured polymer covers can be used for biological isolation in health care areas, as a protective barrier to control the spread of infections. 

scholarly journals Highly Loaded Cellulose/Poly (butylene succinate) Sustainable Composites for Woody-Like Advanced Materials Application

Molecules ◽  
2019 ◽  
Vol 25 (1) ◽  
pp. 121 ◽  
Author(s):  
Oskars Platnieks ◽  
Sergejs Gaidukovs ◽  
Anda Barkane ◽  
Gerda Gaidukova ◽  
Liga Grase ◽  
...  
Keyword(s):  
Fold Increase ◽  
Advanced Materials ◽  
Butylene Succinate ◽  
Alkyl Chains ◽  
Uniform Dispersion ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis ◽  
Polymeric Diphenylmethane Diisocyanate ◽  
Polymer Crystallinity

We report the manufacturing and characterization of poly (butylene succinate) (PBS) and micro cellulose (MCC) woody-like composites. These composites can be applied as a sustainable woody-like composite alternative to conventional fossil polymer-based wood-plastic composites (WPC). The PBS/MCC composites were prepared by using a melt blending of 70 wt% of MCC processed from bleached softwood. MCC was modified to enhance dispersion and compatibility by way of carbodiimide (CDI), polyhydroxy amides (PHA), alkyl ester (EST), (3-Aminopropyl) trimethoxysilane (APTMS), maleic acid anhydride (MAH), and polymeric diphenylmethane diisocyanate (PMDI). The addition of filler into PBS led to a 4.5-fold improvement of Young’s modulus E for the MCC composite, in comparison to neat PBS. The 1.6-fold increase of E was obtained for CDI modified composition in comparison to the unmodified MCC composite. At room temperature, the storage modulus E′ was found to improve by almost 4-fold for the APTMS composite. The EST composite showed a pronounced enhancement in viscoelasticity properties due to the introduction of flexible long alkyl chains in comparison to other compositions. The glass transition temperature was directly affected by the composition and its value was −15 °C for PBS, −30 °C for EST, and −10 °C for MAH composites. FTIR indicated the generation of strong bonding between the polymer and cellulose components in the composite. Scanning electron microscopy analysis evidenced the agglomeration of the MCC in the PBS/MCC composites. PMDI, APTMS, and CDI composites were characterized by the uniform dispersion of MCC particles and a decrease of polymer crystallinity. MCC chemical modification induced the enhancement of the thermal stability of MCC composites.

scholarly journals Synthesis and Characterization of Fibrous Bimetallic CuPt Nanoparticles

2016 ◽  
Vol 1 (1) ◽  
Author(s):  
Elvy Rahmi
Keyword(s):  
Indium Tin Oxide ◽  
Lattice Mismatch ◽  
Fibrous Structure ◽  
Transfer Reactions ◽  
Individual Element ◽  
Key Factor ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis ◽  
Charge Transfer Reactions

<p>This paper reports a facile methode for the synthesis of fibrous bimetallic CuPt Nanoparticles (CuPt NPs) using the liquid phase deposition methods deposited directly on an indium-tin oxide (ITO) substrate. The electron microscopy analysis result shows that CuPt NPs, constructed by networked-nanorod of diameter ca. 3.5 nm and length approximately 5.5 to 6.5 nm, exhibits a quasi spherical morphology and fibrous structure with diameter approximately 196±98 nm. The differences of individual element miscibility and the effect of lattice-mismatch between Pt and Cu is the key factor for the formation of fibrous structure. XPS analysis indicated that the fibrous bimetallic CuPt NPs feature metallic properties with highly reactive surface. This may increase the charge-transfer reactions in catalytic, electrochemistry and sensors application.</p><p> </p>

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