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Challenges

We are attempting to classify and count the different subspecies of WBC in multi-cell images using morphological features. This is a challenging and ongoing problem explored by many independent researchers, and there is no standard solution. While shape and feature recognition is easy to humans, it is one of the most researched topics in machine learning. Most methods divide the process into two subsystems, segmentation and classification.

Past methods

Segmentation

We must segment each cell image into the nucleus and cell body in order to extract features. The first problem is cell isolation. Most researchers cropped the individual cells manually due to the difficulty in isolating overlapping circles (WBCs and red blood cells) which can be seen in Figure 1. Several methods for segmentation have been explored in the literature.

Overlapping Blood Smear.

Figure 1. Overlapping can be seen between RBCs and WBCs.

Green channel filtering is a common way to isolate WBCs in colored blood smear images. Red blood cells (RBCs) and white blood cells separate into two distinct peaks in this space (with number of pixels on the y axis and color value, 0 to 255 on the x axis). The white blood cells have more green content. Furthermore, the WBC nuclei also differ slightly from the cytoplasm in green content. [1] However, this method requires extremely consistent and high quality images due to the subtleties associated with the different cells’ green channel content.

Grayscale images and thresholding can also be used to separate the RBCs, WBCs, and WBC nuclei. WBC cell bodies appear much darker than RBCs, and WBC nuclei appear darker than cell bodies. Several thresholds can be used to differentiate between the cells. [2] For example, in “White Blood Cell Segmentation Using Morphological Operators and Scale-Space Analysis,” a hard-coded threshold was used to isolate the first seed. Then, another equation was used to improve the gradient extracted. This was repeated for 10 iterations. [3]This method requires the images to be high resolution, because blur and graininess can cause individual areas of darker or lighter spots.

Some researchers use a combination of both common methods in order to obtain the best results. They first localize the nuclei using color analysis, and then threshold for finer boundaries. [1]

Past classification methods

We found that many research articles used both morphological and texture features for classification. These are based mostly on nucleus shape. Recall that the subtypes of WBCs have lobed nuclei which differ between the types. In the literature, monocytes are the most difficult to classify, often mistaken lymphocytes and neutrophils.

Most research papers implement at least ten features. These features must differ significantly between the cell types. They include a variety of area, perimeter, and color characteristics. The papers that used colored images have more features than grayscale due to the differences in color content as mentioned above. Below are example categories that have been explored.

    Intensity and color based features

  • Mean and variance of color distances for cell, cytoplasm, and nucleus

    Texture based features

  • Contrast of cytoplasm and nucleus
  • Homogenicity of cytoplasm and nucleus
  • Entropy of cytoplasm and nucleus

    Shape based features

  • Area of cell and nucleus
  • Ratio of nucleus area over cell area and perimeter length
  • Nucleus shape features
  • Number of nuclei

Common classification methods include k-nearest neighbors, learning vector quantization, Multi-layer perceptrons, and support vector machine (SVM). These are pattern recognition algorithms, which makes sense for this application. We found that the most successful paper, which used 57 features in total from all three categories above, had an accuracy of 91% for SVM. [3]

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Automatic white blood cell classification using svm and neural networks. OpenStax CNX. Dec 16, 2015 Download for free at http://legacy.cnx.org/content/col11924/1.5
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