Category Archives: Biological Sciences

Usage of mathematics for an understanding of how the brain functions

Posted on April 5, 2018 by | Leave a comment

When a tree falls in the middle of a forest and nobody heard it falling, can it be considered as a sound? Well, to answer this question, mathematics can guide us to understand how our vision and hearing works.

Priscilla Greenwood, a mathematicians and  Lawrence Ward, a neuroscientist at the University of British Columbia worked together on a research that explains how we perceive the things that occur around us as a part of our brain receives signals. Based on the enough patterns of the signals that occur when we use our senses, it is possible for a computer to imitate a real brain.

A part of our brain that lights up when we perceive things around us
Photo Credit: Flickr

To understand the pattern of the signals that our brains receive, we first need to encounter the shape of a Mexican hat, which is a shape of a tiny area of nerves that changes when we see an image. The pointy part of the diagram below shows the area of focus where the nerves respond the most and the dented area represents the area that we mostly ignore when encountering an image. In other words, as we pay more attention to a specific area, we automatically pay less attention to other areas.

A diagram of the Mexican Hat.
Image from https://commons.wikimedia.org/wiki/Category:Spontaneous_symmetry_breaking#/media/File:Mexican_hat_potential_polar.svg

We had the opportunity to interview Dr. Ward about the research for the better understanding of the concepts. Dr. Ward elaborated more on the activity of the tiny neurons in our brains in patterns, which matches with a shape of sombrero (similar to the Mexican hat shape). Listen to the explanation of their research in the following podcast.

Podcast credit: Kang Zhihao

Why did they choose the Mexican hat equation particularly to explain how we perceive the randomness of things? It is because it is a most suitable way to describe the aspects of brain activity and the pairing of the neurons and to calculate how we perceive sights around us. In the video below, Dr. Ward describes how a form of wave  of neural activity exist in our brain that varies according to the level of activity based on the activity of our senses.

Video Credit: Huanxin Zhang, https://www.youtube.com/watch?v=rHORreeISC4&feature=youtu.be

What can we do with the information from this research? The important findings of this study may help us to construct a model that has a similar level of intelligence that a real brain consists. Also, the mathematics can be applied to recreate brain simulations possibly in the future, but the real brain still outlasts the machines. The answer to the question that was asked in the beginning, is that in order for us to hear the tree that falls in the middle of the forest depends on how high can the Mexican hat of our brain be.

-Group 5: Aaron yen, Zhihao Kang, Huanxin Zhang, Victoria Park 

Video credit:

o Pattern Dynamics of Reaction Diffusion Equation: ak0amay Published on Oct 10, 2015 o Brain model: Growing a Brain Pattern: Particle Skull, Published on Jul 9, 2014 o What Are Brain Waves?: MinuteEarth, Published on Nov 7, 2017 o The brain waves when noised involved: Relaxing White Noise, Published on Feb 10, 2015 o Brain patterns in math: École polytechnique fédérale de Lausanne (EPFL), Published on Jun 12, 2017 Thanks to Dr. Janet Ochola and Dr. Andrew Trites for guidance and advice during the project. Thanks to Dr. Priscilla Greenwood for the insight and Dr. Lawrence Ward for the explanations.

Audio credit:

The background musics are public domain and licensed from y.qq.com

 

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Posted in Biological Sciences, Issues in Science, Outreach Project, Science Communication, Science Communicators, Science in News

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Tackling Cancer: Organogels to the Rescue

Posted on April 4, 2018 by | Leave a comment

“Cancer” —  a word that brings fear among the public because ‘incurable’ is what first comes to mind. Drug industries and researchers have spent countless hours to develop a cure against this fatal disease. However, due to rapid advancements in science, what if we are inching closer towards a solution on eliminating cancer? Would that put the public more at ease? To this day, only a handful of cancers are curable such as prostate cancer, thyroid cancer, testicular cancer, and breast cancer. A recently discovered structure called an organogel offers an attractive approach in helping to combat cancer.

Source: Image of organogel, provided by Dr. Roy van der Meel

What are organogels?

Organogels act as a delivery system that carry drug particles, protect the drug particles, and make their way to cancer cells where it releases the drug contents. Drugs often contain small particles that bind and interfere with proteins made by virus and cancer cells. These particles are called small interfering ribonucleic acid (siRNA). RNA is present in all living cells where it has a role in controlling protein synthesis. Upon binding of siRNA to its target (cancer cells/viruses), the production of harmful proteins from cancer cells in our body will be stopped. Preventing harmful protein production will prevent cancer from forming in our bodies and eventually killing cancer cells. This is the general basis of how pharmaceutical drugs work.

We had the chance to interview Dr. Roy Van der Meel, a postdoctoral research fellow at UBC. In his research, Dr. Van der Meel and his colleagues showed that the use of organogels is very efficient against harmful cells. He found that organogels were able to locate and bind to cancer cells, and successfully release its contents. To learn more about this technique and its impact in the world, view the video below.

 

What makes organogels so special?

What sets the organogel technique apart from others is that organogels are able to bind to deep tissues within our bodies that are difficult to access. Furthermore, use of organogels contain less severe side effects compared to other methods such as chemotherapy , radiotherapy and surgery. Organogels are biodegradable. This means the body is able to successfully break down the components of the organogel, which minimizes the amount of harm on the body.

Even though this technique has many advantages, there are a few challenges and limitations that accompany it. The small interfering RNA (siRNA)  can be easily damaged by physiological factors in the body which makes it difficult to successfully deliver siRNA to the targeted tissue. Furthermore, injection of organogels is minimally invasive but can have side effects such as short lifetime of siRNA, low renewal efficiency of siRNA, and harming body tissues.

Moving forward into the future

The discoveries and findings in the study provide a basis for the technique of organogels, which still has room to grow. The newly developed technique provides a platform for future research on cancer therapy. Listen to the podcast below to find out more on how this technique can be implemented in the future!

Source: BenSound

Group 1: Aron Ha, Simranjit Singh, Cyndi Yan, Yuuki Shibutani

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Stephen Hawking and the ALS disease

Dr Stephen Hawking Physics professor and author at Cambridge University

Less than a week ago, beloved cosmologist and theoretical physicist Stephen Hawking, science’s brightest star, died at the age of 76 in the morning on Mar.14. His brilliance and persistence has inspired people around the world. People who are not specialist in physics may have not heard of his four laws of black hole mechanics or the Hawking radiation, but often have heard of his courageous story and lifelong battle with the amyotrophic lateral sclerosis disease (ALS).

While studying at Oxford, the young Stephen Hawking was diagnosed with ALS – a disease that causes death of neurons and gradually paralyses voluntary muscles – at the age of 21, in 1963. The doctor gave him a life expectancy of less than three years, but Stephen Hawking have defied the odds and coped with the daunting disease for over half a century. He spent 30 years as mathematics professors at the University of Cambridge, published the world-renowned The Universe in a Nutshell and A Briefer History of Time, which introduced cutting edge findings in theoretical physics to millions of readers. While Lou Gehrig and other people that suffer from ALS usually succumb in less than ten years, why has Hawking beat the odds and lived with the formidable disease?

Illustration of a normal nerve structure (left) and an ALS affected nerve cell (right)

Amyotrophic lateral sclerosis is a highly variable disorder and can be classified a few different ways: by where the motor neuron is first affected, and by how fast the disease progresses. Hawking was an outlier, the neurons that control the diaphragm and swallowing muscle are not severely deteriorated, that means breathing muscle functions properly, malnutrition and dehydration which are often found in other cases would not be seen on Hawking.

The disorder progression also tends to be slower in people with onset at less than 40 years old, the reason behind this remains unknown. Hawking’s case is very similar to juvenile amyotrophic lateral sclerosis, which progresses very slowly and have a life expectancy of more than 30 years. And like his mind, Hawking’s illness seems to be singular. Hawking’s longevity is partly due to the excellent care that he received, and more importantly – the biology of his form of the neurodegenerative disease. Stephen Hawking’s case is a unique example of the variability of the disease, he not only gives hope to patient who also suffer from the ALS disease, but also inspires millions for his determination to fight against the odds.

Stephen Hawking’s contribution to physics and cosmology will live in the annals of science forever.

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Posted on March 19, 2018 by in Biological Sciences, Science Communicators, Science in News

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Negative effects on the brain caused by recreational marijuana

Posted on March 19, 2018 by | 2 comments

Marijuana is one of the three main forms of cannabis (a kind of drug affecting mental activity, behaviour, or perception). It is made from the cannabis plants’ leaves and dried flowers.

cannabis / image from Quick GuideUnderstanding Medical Marijuana

 In all the products of cannabis, marijuana is the least powerful. It is always smoked or even made into eatable products such as marijuana ice cream.

marijuana ice cream /image from Dr Greenlove

Therefore, some teenagers think that the marijuana can not hurt them and some of them even think that using marijuana allows them to be relaxed and settle down and improve their concentration. However, the fact is that recreational marijuana-use by youth can cause negative effects on the brain and daily performance.

 

 

 

The Risky Chemical in Marijuana

The delta-9-tetrahydro-cannabinol (THC), a main chemical in marijuana, is risky for biological systems in the brain.

The chemical formula of THC/ image from Evidence for God from Science

THC affects the cerebellum and the basal ganglia. The cerebellum is the area of the brain which controls balance and coordination. The basal ganglia are the parts of the brain which are helpful for controlling movement. These effects impact performance in some activities, such as sports and driving.

THC and the brain/ image from Collegiate Times

So the THC in marijuana can influences on the cerebellum and the basal ganglia in the brain. Even though THC can affect our brain, the bad thing is that THC percentage in marijuana experienced a dramatical increase from early 1990’s to 2013, which is from 3.73% t0 10%.

 

The Influence on Memory

In teens, the part of the brain for emotion is developed well, while the part of the brain for judgment still not mature. Smith with other researches found in 2001 that in people who use marijuana everyday for about three years, the hippocampus (a region in brain, is related to long-term memory) looked strange.

image from SlidePlayer

The greater differences in shape of the hippocampus, the poorer performance on memory assessment. In a  long-term memory test,  young adults who have never used marijuana scored 18% better compared to heavy marijuana-use youths. So if young people use marijuana, their memory would be affected negatively because of the brain chemistry and brain structure impairment.

In conclusion, recreational marijuana is harmful to the brain if youth uses it, especially when marijuana-use is high potency and long-term.

image from Depositphotos

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