Histochemistry and ultrastructure of Campuloclinium chlorolepis (Asteraceae) tuberous roots accumulating fructan: evidences of functions other than reserve carbohydrate

2011 ◽  
Vol 59 (1) ◽  
pp. 46 ◽  
Author(s):  
Divina A. A. Vilhalva ◽  
Angelo L. Cortelazzo ◽  
A. L. Maria Angela M. Carvalho ◽  
Rita de Cássia L. Figueiredo-Ribeiro
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Performance ◽  
Anion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Cortical Tissue ◽  
Tuberous Roots ◽  
Polarised Light ◽  
Reserve Carbohydrate ◽  
Scanning Electron

Campuloclinium chlorolepis (Baker), an herbaceous species of the Cerrado, accumulates inulin-type fructans in the tuberous roots. Plants were collected in the Cerrado and the roots analysed using light and scanning electron microscopy. The presence of fructans was assessed by specific stain reactions and by high performance anion exchange chromatography. Here, we report the localisation of protein, phenols and neutral polysaccharides in the tuberous roots after staining with different dyes generally used in cytochemical analyses. Results showed the presence of fructans inside and outside cells from all tissues of tuberous roots with the exception of the epidermis. When visualised by scanning electron microscopy, globular bodies consistent with typical inulin spherocrystals were clearly detected under polarised light. These globular bodies varied in size according to location, being smaller in the cortical tissue and larger in the central cylinder. The localisation of fructans outside the cell in several tissues of the tuberous roots clearly shown by histochemical and ultrastructural analyses lead to the hypothesis of interaction of fructose polymers with cell membrane and possibly their role in membrane stabilisation in plants subjected to stressing environmental conditions.

The bright future of digital imaging in scanning electron microscopy

1993 ◽  
Vol 51 ◽  
pp. 768-769
Author(s):  
M. T. Postek ◽  
A. E. Vladar
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Digital Imaging ◽  
High Speed ◽  
High Performance ◽  
Mass Storage ◽  
Analog To Digital ◽  
Central Processing ◽  
Digital Imaging Technology ◽  
Scanning Electron

One of the major advancements applied to scanning electron microscopy (SEM) during the past 10 years has been the development and application of digital imaging technology. Advancements in technology, notably the availability of less expensive, high-density memory chips and the development of high speed analog-to-digital converters, mass storage and high performance central processing units have fostered this revolution. Today, most modern SEM instruments have digital electronics as a standard feature. These instruments, generally have 8 bit or 256 gray levels with, at least, 512 × 512 pixel density operating at TV rate. In addition, current slow-scan commercial frame-grabber cards, directly applicable to the SEM, can have upwards of 12-14 bit lateral resolution permitting image acquisition at 4096 × 4096 resolution or greater. The two major categories of SEM systems to which digital technology have been applied are:In the analog SEM system the scan generator is normally operated in an analog manner and the image is displayed in an analog or "slow scan" mode.

scholarly journals Boosting the Adhesivity of π-Conjugated Polymers by Embedding Platinum Acetylides towards High-Performance Thermoelectric Composites

Polymers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 593 ◽  
Author(s):  
Tao Wan ◽  
Xiaojun Yin ◽  
Chengjun Pan ◽  
Danqing Liu ◽  
Xiaoyan Zhou ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Conjugated Polymers ◽  
High Performance ◽  
Single Walled Carbon Nanotubes ◽  
Strong Interactions ◽  
Transmission Electron ◽  
Higher Power ◽  
Walled Carbon Nanotubes ◽  
Scanning Electron

Single-walled carbon nanotubes (SWCNTs) incorporated with π-conjugated polymers, have proven to be an effective approach in the production of advanced thermoelectric composites. However, the studied polymers are mainly limited to scanty conventional conductive polymers, and their performances still remain to be improved. Herein, a new planar moiety of platinum acetylide in the π-conjugated system is introduced to enhance the intermolecular interaction with the SWCNTs via π–π and d–π interactions, which is crucial in regulating the thermoelectric performances of SWCNT-based composites. As expected, SWCNT composites based on the platinum acetylides embedded polymers displayed a higher power factor (130.7 ± 3.8 μW·m−1·K−2) at ambient temperature than those without platinum acetylides (59.5 ± 0.7 μW·m−1·K−2) under the same conditions. Moreover, the strong interactions between the platinum acetylide-based polymers and the SWCNTs are confirmed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) measurements.

scholarly journals The Bright Future of Digital Imaging in Scanning Electron Microscopy

1994 ◽  
Vol 2 (4) ◽  
pp. 19-20 ◽  
Author(s):  
M.T. Postek ◽  
A.E. Vladar
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Digital Imaging ◽  
High Speed ◽  
High Performance ◽  
Mass Storage ◽  
Analog To Digital ◽  
Central Processing ◽  
Digital Imaging Technology ◽  
Scanning Electron

One of the major advancements applied to scanning electron microscopy (SEM) during the past 10 years has been the development and application of digital imaging technology. Advancements in technology, notably the availability of less expensive, high-density memory chips and the development of high speed analog-to-digital converters, mass storage and high performance central processing units have fostered this revolution. Today, most modern SEM instruments have digital electronics as a standard feature. These instruments, generally have 8 bit or 256 gray levels with, at least, 512 X 512 pixel density operating at TV rate. In addition, current slow-scan commercial frame-grabber cards, directly applicable to the SEM, can have upwards of 12-14 bit lateral resolution permitting image acquisition at 4096 X 4096 resolution or greater.

scholarly journals Synthesis and Characterization Molecularly Imprinted Polymers for Analysis of Dimethylamylamine Using Acrylamide as Monomer Functional

2018 ◽  
pp. 76-84
Author(s):  
Saeful Amin ◽  
Sophi Damayanti ◽  
Slamet Ibrahim
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Size Structure ◽  
Imprinted Polymer ◽  
Morphological Form ◽  
Molecularly Imprinted ◽  
Scanning Electron

A selective separation techniques with Molecularly Imprinted Polymer (MIP) for High-Performance Liquid Chromatography (HPLC) has been developed for the assay of Dimethylamylamine (DMAA) doping compounds. Molecular imprinted polymer (MIP) is a technique to produce a polymer having the cavity due to the disposal of the templates, in which the cavity serves to recognize the molecules of the same size, structure, chemical and physical properties. The selectivity and affinity of the templates itself will increase, while the concentration value is increasing. MIP is made by DMAA as template, acrylamide as functional monomer, ethylene glycol dimethacrylate (EGDMA) as cross linking, azobisisobutyronitrile (AIBN) as the initiator and chloroform as a porogen solvent; using bulk method. The aim of research are conduct the MIP for the DMAA compound analysis, then the formed MIP is characterized by using Fourier Transform Infra Red (FTIR) and Scanning Electron Microscopy (SEM) to find out the polymer complexes formed and the morphological form of the MIP. The MIP formed then was analyzed by using High-Performance Liquid Chromatography (HPLC) to know the amount of the DMAA, the adsorption capacity, and the adsorption condition found in the MIP. The result of analysis on the content of DMAA in the MIP by using UV-Vis Spectrophotometer is 1.957 mg. Scanning Electron Microscopy (SEM) shows that the MIP has irregular and rough morphological structure; while the NIP has irregular morphology structures and smooth surfaces shape

High resolution Scanning Electron Microscopy

1989 ◽  
Vol 47 ◽  
pp. 6-7
Author(s):  
David C. Joy
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Resolution ◽  
High Performance ◽  
Secondary Electron ◽  
Wide Energy Range ◽  
Wide Energy ◽  
Electron Microscopes ◽  
Electron Imaging ◽  
Scanning Electron

High resolution scanning electron microscopy is still a relatively new and unfamiliar concept because in the early days of the SEM it was expected, that secondary electron imaging would be limited to a resolution of between 5 and 10nm at best. Now, however, because of improvements in instrumentation and technique based on advances in the understanding of electron beam interactions with solids current SEMs can demonstrate spatial resolutions below 1nm, rivaling those obtained by transmission instruments.High performance scanning electron microscopes always incorporate two advanced items of instrumentation. Firstly they use field emission guns (FEGs). The high brightness, low energy spread, and small source size of the FEG makes it possible to produce an electron probe of sub-nanometer size which contains sufficient current for secondary electron imaging (i.e 10-12 amps or more) and which can maintain this performance over a wide energy range (3 to 30keV). Secondly, the new high performance instruments place the specimen within a high excitation, immersion, probe forming lens.

scholarly journals Remineralization Potential of Three Tooth Pastes on Enamel Caries

2017 ◽  
Vol 5 (5) ◽  
pp. 664-666 ◽  
Author(s):  
Rajnish K. Singhal ◽  
Balwant Rai
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
In Vitro Study ◽  
Fluoride Content ◽  
Significant Difference ◽  
Polarised Light ◽  
New Formulation ◽  
Scanning Electron

BACKGROUND: Different formulations of dentifrices exist in the market. Usually, single toothpaste is used by all family members including children. There is a big concern of fluoride ingestion with the toothpaste containing high fluoride content in children. Recently, new toothpaste (including toothpaste) with remineralization potential without fluoride content has been formulated.AIM: There is an urgent need to compare remineralization potential of this new formulation with the exiting dentifrices. Therefore, the present study has been undertaken to assess and compare the remineralization potential of three dentifrices with different compositions on artificially induced carious lesions in vitro by using scanning electron microscopy and polarised light microscopy.MATERIALS AND METHODS: The present in vitro study was conducted on 21 healthy extracted primary central incisor teeth surfaces, which were divided into three groups and were treated by three different dentifrices. Artificial demineralization was followed by remineralization using dentifrice slurry as per the group distribution. All the samples were studied for remineralization by using scanning electron microscopy and polarised light microscopy. Data were analysed using SPSS version 11 software.RESULTS: A significant difference was found between the remineralization potential of  incudent toothpaste and other toothpaste groups based on the analysis of polarised light microscopy and stereomicroscope. The remineralizing ability of  incudent toothpaste for artificial enamel lesions was found to be significantly higher than that of Colgate® and Crest toothpaste.CONCLUSIONS: The limitations of this study include, being a short term study, low sample size and in vitro experiment.  incudent toothpaste has exhibited a higher remineralizing potential as compared to fluoride based toothpaste in our study.

Comparison of Scanning Electron Microscopy and Light Microscopy for the Diagnosis of Early Stages of Brown Rot Wood Decay

IAWA Journal ◽  
1993 ◽  
Vol 14 (3) ◽  
pp. 219-226 ◽  
Author(s):  
W. Wayne Wilcox
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
Cell Walls ◽  
Wood Decay ◽  
Brown Rot ◽  
Early Stages ◽  
Polarised Light ◽  
Scanning Electron

As part of a larger study of the microscopical characteristics useful in diagnosing early stages of decay, an opportunity was created to compare the ability of light microscopy (LM) and scanning electron microscopy (SEM) to image these features. Although most features could be imaged by both technologies, imaging was much easier in the SEM because it was being used at the low end of its resolution and magnification capability while the LM was near the high end of its limitations. One important feature which could not be imaged in SEM was the earliest attack on the cell walls, a feature which was visible under polarised light in the LM.

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