Category Archives: Issues in Science

The Mystery Of How The Zebra Got Its Stripes

Posted on February 1, 2015 by | 4 comments

Why is the sky blue? Why did the cheetah get all the speed? Why do zebras have stripes? These are all questions that we wonder about the world around us. Fortunately scientists are working on answers in regards to zebras and their magnificent stripes.

In the plains of Africa, striping varies regionally. In some areas zebras have thick black and white striping covering their entire body, while in other areas zebras have thin stripes, with some parts of the body having no striping at all. In the past, many ideas have been developed to explain why zebras have stripes and to explain the variation in their stripes. Perhaps their stripes make it difficult for predators to predict their size and speed, therefore protecting them from capture. Perhaps the stripes cause an optical illusion that confuses biting flies in their habitat. Perhaps their stripes evolved for thermoregulation (the process of cooling and heating the body to the correct temperature) or social unity.

Predicted levels of stripe thickness on hind leg (left) and torso stripe definition (right). Image Courtesy of: Royal Society Publishing

Predicted levels of stripe thickness on hind leg (left) and torso stripe definition (right).
Image Courtesy of: Royal Society Publishing

Recent studies have found that the amount of striping on a zebra, and the intensity of that striping can be predicted by the temperature of the environment these zebras are living in. In hotter, drier areas, zebras have thicker stripes. Thinner stripes are seen farther from the tropics, in
slightly cooler areas. This pattern was seen on the torso, with the legs being a bit harder to predict.

This finding supports the thermoregulation hypothesis that states the thicker the stripes on the zebra, the more the heat difference between the black and white stripes. This causes eddies of air that have a cooling effect on the zebra’s body temperature.

Image Courtesy of: Wikimedia Commons

Additionally, a non-contact thermometer gun was used to compare the surface body temperature of zebras with herbivores of approximately the same size in the same area. This non-contact thermometer gun is simply pointed at the animal, and then it takes a reading of the infrared energy emitted by the animal and the animal’s temperature can be determined. It was found that zebras had an average body temperature of 29.2◦C, which was significantly lower than herbivores of the same size with a body temperature of 32.5◦C.

This relationship between temperature and striping patterns on zebras gets us one step closer to determining the functionality of zebra stripes. However, the cause of the correlation between temperature and striping patterns is still not fully understood and further investigation is needed.

Posted by: Alex Ensing

4 Comments

Posted in Issues in Science, Science in the News

Tagged , , , ,

Moving Beyond Silicon: Taking on Moore’s Law with Photonics

Posted on January 26, 2015 by | Leave a comment

“It can’t go on forever. The nature of exponentials is that you push them out and eventually disaster happens”

This stark comment made in 2005 by Gordon E. Moore, a co-founder of Intel, has served as a wakeup call for computer scientists who have known for nearly forty years that mainstream manufacturing processes for computer circuitry will soon become obsolete.

Ever since its original conception in 1965, Moore’s Law has predicted that roughly every two years, the number of transistors put into a computers central processing unit (CPU) will double. Moreover, each time the amount of transistors doubles,  Why should you care about this trend? First, progress in the development of the increasingly intelligent technologies that effect our lives relies heavily on this trend. Insofar as over time, we depend on our computers becoming faster, while simultaneously staying cool, small and economic to operate; so that we can innovate with them.

PPTMooresLawai

Much of human progress, from consumer electronics to medical breakthroughs, relies on the Moore’s Law continuing for the foreseeable future. Credit: Ray Kurzweil and Kurzweil Technologies, Inc. (Wikimedia Commons)

Second, Intel has predicted that as soon as 2021, new strategies for designing computer hardware will need to be implemented or development of exciting new technologies will be stunted dramatically. Consequently, computer scientists have been researching the future of manufacturing the CPU, and the prospects are encouraging.

Optoelectronics_experiment

An electro-optics researcher experiments with routing lasers. Credit: Adelphi Lab Center (Wikimedia Commons)

 

Take for instance, silicon photonics, a development in CPU design that will allow signals to be processed within the computer using lasers which guide photons  rather than traditional electronic circuits which pass information using electrons. Silicon photonics develops computing in two key ways. First, a hybrid silicon laser can be used to encode information using pulses of light and pass the laser through guides to transmit information quickly to other parts of the computer.

2108713905_44d262678d_o

The new technology by IBM allows for electrical signals to combined with the light produced by a laser and create short pulses of light. These pulses can then be routed around the inside of a computer to transmit information at speeds much faster then our modern computers can accomplish today. Credit: ibmchips (Flickr Commons)

 

Second, a laser can be passed through specially designed optical logic gates, made from crystals with a non-linear refractory index, to perform arithmetic and logical operations within the computer’s processing unit at light speed.

5228755628_8a6e249b49_o

By utilizing specially manufacturing crystals, the new technology produced by IBM can create logic gates, the fundamental circuitry that makes decisions inside the CPU, that utilize light rather than the traditional electronic circuity. Not only does this have the benefit of fast-as-light speeds, but the circuitry operates cooler than the modern computer and utilizes far less electricity. Credit: Programmazione.it2010 (Flickr Commons)

 

In December of 2012, IBM announced that it had designed and created a hybrid silicon photonics-electronic chip, and not only that, but they also managed to integrate the monolithic manufacturing process used to make CPUs today.

This breakthrough by IBM in silicon photonics found two key benefits. First, there is the difference in performance. Where traditional CPUs are able to move data around the computer in the mere gigabytes per second, comparatively, tests on the new IBM photonics chip show the speed to be in the terabytes per second. From this capability, IBM has predicted that communication between computers, or between CPUs within a computer, could see a speed increase by a factor of one thousand. Second, because IBM was able to use a similar manufacturing process, that is not too different from the way CPUs are made today, this means that this technology could be offered commercially quickly, cheaply and integrate with current computer hardware almost seamlessly.

So what does this mean for the future of computation? Will silicon photonics contribute to the forthcoming revolution in computer manufacturing? Tell me what you think and stay tuned for part two when I look at developments in new materials that will shape the computers of the future.

For a more detailed breakdown of the silicon photonics, check out the presentation given by the Director of the Institute for Energy Efficiency and Kavli Professor of Nanotechnology at the University of California Santa Barbara, John Bowers. Bower’s presentation at the 2014 European Conference on Optical Communications provides some of the finer details of this exciting new technology in the video below:

YouTube Preview Image

– Corey Wilson

Leave a comment

Posted in Issues in Science

Tagged , , , , , , , ,

Analog vs. Digital Synthesizers – What Are They, and Which Makes Better Music?

Posted on January 26, 2015 by | Leave a comment

In 1983, the music world was shaken by the introduction of a new instrument, the Yamaha DX7. The DX7 was the first digital synthesizer – the first instrument to generate sounds from data – to overcome the challenges of its digital predecessors and experience commercial success. It was both portable and affordable, and it had new features its analog predecessors lacked such as the ability to save sounds in digital memory for later. The DX7 went on to shape the sound of much of the music in the 80s and 90s, and it is credited with bringing about the decline of analog synths.

Analog synthesizers don’t seem to be gone for good, though. Many companies are beginning to make analog synths again. For example, Korg recently reissued its classic MS20 and Dave Smith Instruments recently announced the all-new Prophet 6. Given the advantages of digital instruments, why are companies bothering? Why is there a demand for new analog instruments? The answer lies in the way they generate sound.

Sound is the variation of pressure in the air as perceived by the eardrum. When sound is recorded with an analog system, it is converted into an electrical signal where the height of the sound wave is proportional to signal strength. A stronger signal will model a taller wave. When sound is recorded on a digital system, wave height is recorded as a number. This means analog systems generate and capture sound continuously while digital systems generate and capture sounds in steps. The tiny loss of detail that comes with capturing sound in steps is called “loss”. So digital systems have loss while analog systems are “lossless”. This is also the reason some people prefer analog sounds to digital sounds – they feel that analog instruments sound more smooth and “liquid” because they create sound continuously instead of in steps.

Two important differences and digital signal are bandwidth, defined as the range of frequencies they can capture, and signal-to-noise or S/N ratio, the ratio of the amount of desired sound to unwanted background noise. Analog system bandwidth is constrained by the quality of the circuits used, and digital system bandwidth is constrained by the sampling rate, the speed at which the system measures a sound wave. In recent years, many digital systems have achieved sampling rates high enough to functionally match the quality of analog sounds, causing many to call into question whether it’s even possible to hear a difference between an analog signal and a digital signal of sufficient quality. Will digital ever really kill analog? Only time will tell. I maintain that both are very useful and relevant types of instruments for music production, depending on the type of sound desired. I’ve attached a video with analog and digital synthesizers from the same company played together for comparison. See which one you like more!

– Erik Johnson

YouTube Preview Image

Leave a comment

Posted in Issues in Science

Tagged , ,

A New Hope For Antibiotics

Posted on January 25, 2015 by | Leave a comment

Your body is constantly under attack from millions of pathogens every day and while most of the time the body’s immune system can take care of the invaders there are instances where outside help is needed. This is where antibiotics become useful. But currently problems are arising with the usage of antibiotics, mostly in the form that many current antibiotics are no longer effective against specific species of invading bacteria, these bacteria are termed antibiotic resistant bacteria. The problem of antibiotic resistant bacteria is one that if left unchecked will grow and might contribute to a mass outbreak of dangerous bacteria.

Antibiotics have become a prominent feature of modern health care and are used to fight and inhibit the growth of bacteria that have invaded your body. When the field of antibiotics was first discovered and expanded upon there was little to no general resistance to the antibiotics commonly used in today’s medical practices.

But resistance has grown as microbial mutations and the misuse of antibiotics has selected for dangerous antibiotic resistant bacteria. Bacteria replicate incredibly quickly and due to their methods of replication their genetic code, DNA, there will be a chance for  mutations, random changes to the new DNA produced, in each new generation of bacteria. These mutations can often give bacteria a way of making certain antibiotics useless against them due to how they can change where the antibiotic interacts to interfere with the bacteria. While normally this chance of mutation is low for each bacteria, due to their fast replication rate mutations can  appear quite frequently and cause problems for antibiotic treatments.

The bacteria grown in the petri dish on the left are susceptible to the different antibiotics in the white pills. The bacteria in the right petri dish are resistant to most of the antibiotics in the pills. Image Courtesy of Wikimedia Commons

The bacteria grown in the petri dish on the left are susceptible to the different antibiotics in the white pills. The bacteria in the right petri dish are resistant to most of the antibiotics in the pills; Image courtesy of Wikimedia Commons

These antibiotic resistant bacteria are very dangerous as it is left up to the immune system to fight them and for people that have weaker immune systems this can be dangerous or even lethal.

Some Mycobacterium Tuberculosis bacteria Source: Wikimedia Commons

Bacteria Species Mycobacterium Tuberculosis;  Image courtesy of Wikimedia Commons

While the outlook might look grim for the future of antibiotics there has been a recent study published that reports on finding a new antibiotic, teixobactin, and new possibilities for culturing microorganisms to find new antibiotics. While the discovery of a new antibiotic is an incredible achievement by itself the scientific implications in their tests against two species of bacteria in which they found no resistance to the new antibiotic is massive. In addition to the current lack of resistance to teixobactin the researchers report that the properties of the new antibiotic suggest that resistance is unlikely to develop against it as it acts on a structure of the bacteria that is highly unlikely to change due to its specific functionality of the bacteria’s life cycle.

Teixobactin was found by examining uncultured bacteria. Uncultured bacteria, which are bacteria that have yet to be grown in a lab, make up most of the population of bacteria on the planet and are a huge potential source for future antibiotics. The study reports on developing new ways to successfully culture these previously uncultured bacteria and this is highly significant as it opens doors to discovering more antibiotics that do not have resistance developed against them yet.

With this discovery the research field of antibiotics might be rejuvenated as new populations of bacteria are now able to be grown due to the new methods of culturing previously uncultured bacteria developed in the study. In the future be on the lookout for teixobactin because it might be the answer to a dangerous bacterial infection that affects you.

– Matthew Leupold

Leave a comment

Posted in Biological Sciences, Issues in Science, Science in the News

Tagged , , ,

Living LARGE

Posted on January 25, 2015 by | 1 comment

What do you think of when you hear the phrase “living large”? Well, most of us will think of an individual who is living life to the extreme, maybe spending a ridiculous amount of money or living a very extravagant lifestyle. However, for far too many parents and children in North America, “living large” has a very serious and negative connotation. I am referring to the epidemic of obesity in children in North America. Fortunately, a new study has shown that a program that aims to reduce childhood obesity is working well in the U.S.

The study, “Changes in Body Mass Index Associated With Head Start Participation” focuses on a program funded by the U.S. government for low income households. The Head Start program focuses on health, nutrition, exercise, and early education for the young children. Basically, the program promotes healthy living and provides a well-structured plan to achieve it. The program includes health and nutritional services, such as meal plans, activity outlines, and family counselling.  The study looked at two groups of children, one with a healthy BMI and another who were overweight or obese. The researchers monitored the children’s BMI throughout two academic years. The study led by Dr. Lemung found that children who were obese  and overweight who participated in the program had a significantly healthier BMI by kindergarten than those who were in a primary health care system.

Medical_complications_of_obesity

Complications of Obesity Source: Wikimedia Commons

Furthermore, a recent CBS news article published in January 2015 focused on the obesity epidemic amongst children in the United States. The article states that about a quarter of the children from ages two to five are either obese or overweight. Moreover, it states that as children enter adulthood, obesity seems to follow. Unsurprisingly, this trend is noted to lead to future health risks for the children. The health risks include a higher chance of developing diabetes, heart disease, lung disease, and much more.

Healthy Fruits & Vegetables

Nutritional Food Choices, Source: Flickr Commons

 

Unsurprisingly, young children living large with no plans to improve their health can threaten their future wellbeing. We need to ensure younger generations are able to thrive in the future and not be held back by complications of obesity. Fortunately, programs such as Head Start have shown to prevent and treat obesity at a very young age. In conclusion, more programs and preventative measures for obesity should be implemented around the world. In turn, these type of initiatives will provide a great way to ensure children get a “head start” in living healthy and not LARGE.

Check out the video created by Jessie Deen for more information on childhood obesity and prevention:

YouTube Preview Image

Posted By: Navjit Moore

1 Comment

Posted in Biological Sciences, Issues in Science, Science Communication, Science in the News

Tagged , ,

Will Your Next Friend Be A Computer?

Posted on January 18, 2015 by | Leave a comment

How do you feel if computers know your personality better than your best friends and even your parents? Feeling awful and scared?

A recent study (“Computer-based personality judgments are more accurate than those made by humans”) shows that computers are able to predicate a person’s personality more accurately than one’s friends and family members.

Picture Credit:http://pakseoexpert.com/

By analyzing digital footprint (“likes” on Facebook), a research group at The University of Cambridge suggests that people’s personalities can be predicated automatically and without involving human social-cognitive skills.

In the computer personality judgments study, researchers used a sample of 86,220 volunteers, who filled in the 100-item personality questionnaire through an application called myPersonality project on Facebook and also tracked their Facebook Likes.

The results of analyzing the collected data, researchers realized that the result of the study highly aligned the Big Five theory. (The five factors are openness, conscientiousness, extraversion, agreeableness, and neuroticism.) For example, volunteers with high openness tend to like meditation or TED talks, and participants with high extroversion tend to enjoy partying or dancing.

In order to study the human personality judgments, researchers obtained from participants’ friends on Facebook and asked their friends to give a 10-item version of a personality measure about a given participant.

By comparing with participants’ self reports, the results show that those computer-based models are more accurate than humans in personality judgment.

At the end of the article, researchers concluded that computers gave more accurate  personality report than a person’s friends, partners and even parents.

“In the future, computers could be able to infer our psychological traits and react accordingly, leading to the emergence of emotionally-intelligent and socially skilled machines.”

“In this context, the human-computer interactions depicted in science fiction films such as ‘Her’  (“Her” is a movie which is released in 2013. The film follows Theodore Twombly, a man falls in love with a computer system that speaks with a female voice.) seem to be within our reach.”

—–Wu Youyou

Picture Credits:http://www.gsmnation.com

However, researchers couldn’t deny that privacy concerns came out because computers can collect amount of information about an individual.

“Big Data and machine learning provide accuracy that the human mind has a hard time achieving, as humans tend to give too much weight to one or two examples, or lapse into irrational ways of thinking.”

“We hope that consumers, technology developers, and policy-makers will tackle those challenges by supporting privacy-protecting laws and technologies, and giving the users full control over their digital footprints.”

——Dr. Michal Kosinski

Picture Credits: National Magazine(Canada)

In the age of Big Data, online data mining and tracking activities of users cause a big concern of personal privacy. By tracking a person’s activities online, computers are able to give a suggestion for one’s life decisions, such as choosing activities, career paths and even choosing a romantic partner. However, related laws or policies should be set up to protect users’ privacy.

 

By Xindi Wang

Leave a comment

Posted in Issues in Science, Science in the News

Tagged , , ,

Part of our Brain comes from a Virus!

Posted on January 17, 2015 by | Leave a comment

We all have heard at some point the word “virus” and associated it with words like death, illness, non-living, etc. But let me tell you that in reality, this is not always the case. Have you ever considered that viruses can help us discover new cures for brain diseases?

Just recently, Johan Jakobsson, head of research team at the division for Molecular Neurogenetics at Lund University (Sweden), and his team have concluded an investigation that has been published in Cell Reports. It explains that we have acquired virus DNA through the course of evolution as a consequence of viruses’ replication cycle.

Viruses are classified into families by the Baltimore classification, in which one of the characteristics is type of replication. Let me explain how viruses incorporate their DNA into ours, but first here is a video that will help you understand the process. At the beginning, Wayne Hodgkinson explains how regular transcription works, but near the end, he mentions that certain types of viruses perform the reverse process. That is the key mechanism that some viruses use: reverse transcription.

Explaining the video in simpler words, reverse transcription consists of taking the original genetic material of the virus (RNA strand) and convert it into a “fake” DNA. I am providing a diagram that reflects reverse transcription.

Reverse Transcription Process           Source: Google images

In addition, I have created a simple diagram that explains how some viruses insert their DNA into ours.

Created by Leslie Almeyda         Uploaded from personal computer

For long time ago scientists have been aware that viral DNA is present in our brain, but the former has been considered not useful to us; therefore, it has not had much importance. However, Jakobsson and his team have shown that viral DNA is capable of determining which and when genes are expressed in our brain cells. This is due to the virus’ DNA being integrated in the part of our DNA that controls expression of the “baby nerve cells,” which –when they have “grown up”- will become specialized nerve cells. As he says in a press release, “we believe that the role of retroviruses can contribute to explaining why brain cells in particular are so dynamic and multifaceted in their function.”

Let’s recall that there are many (lethal) diseases that are related to the brain, and unfortunately some of them are still untreatable. Now with the discovery that part of our brain is affected by viral DNA, scientists can look deeper into our brain cells and link our genes expression to viral DNA insertion. In Jakobsson’s words, “I believe that this can lead to new, exciting studies on the diseases of the brain. Currently, when we look for genetic factors linked to various diseases, we usually look for the genes we are familiar with. […] Now we are opening up the possibility of looking at a much larger part of the genetic material which was previously considered unimportant.”

In conclusion, we have observed that some viruses are indeed helpful to us and might even lead us to newer and more efficient treatments to cure a variety of diseases. Thank you viruses!

 

-Leslie Almeyda-

Leave a comment

Posted in Biological Sciences, Issues in Science, Science in the News

Tagged , , ,