Category Archives: Uncategorized

Microplastics: A Pollution Worse than Plastic?

Posted on November 10, 2018 by | 3 comments

Source: Providence Trade

As detrimental as this photo looks, today’s plastic pollution is unfortunately not limited to these plastic bags and bottles that line the ocean surfaces. Recently, plastic has begun to affect ecosystems and species in ways we did not ever imagine; in the form of microplastics.

What are Microplastics?

Microplastics are small, barely visible pieces of plastic that ultimately enter and pollute our oceans, streams, rivers, soil and air. They can enter our environment from a variety of sources including cosmetics, textiles and industrial settings, or simply from the plastics we pollute each day. According to a recent study done by researchers in Japan, the abundance of microplastics within the world’s oceans has raised growing concerns amongst environmentalists globally due to their detrimental effects on ecosystems and living organisms, including humans. Unfortunately, due to the small size of microplastics, ranging from 5mm to the diameter of a red blood cell, it is difficult to report the exact amount found in our oceans. Researchers estimate that with around 300 million metric tons of plastic produced each year, trillions of degraded plastic bits may be lurking in the environment, largely unseen.

Source: Andrea Thompson via Scientific American

Microplastics in our ecosystem and in our bodies:

Source: Dr. Marcus Eriksen of Gyres Institute

Since microplastics are, as the name suggests, microscopic, they can be ingested by a wide variety of creatures, including plankton (the basis of the marine food chain). Real harm can be done if microplastics in fish and other species move from their gut into the bloodstream and other organs. A study done by Mark Browne shows physical signs of damage, as the particles jabbing and rubbing against organ walls can cause inflammation, while leaching of hazardous chemicals cause liver damage. These hazards can disrupt the immune functions, growth and reproduction of organisms. Even if individual species do not seem to suffer, their ingestion of microplastics can have a ripple effect when they accumulate within a food chain, as another study shows how the fish do not necessarily excrete the microplastics once ingested.

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Not only are these microplastics found in wildlife species, according to a recent study, we actually ingest them everyday. In addition to being present in packaged food and bottled water they are found in tap water and even in the air we breathe, making it virtually impossible to avoid them.

According to Browne’s research, the amount of microplastics in lakes and soils alone could rival the more than 15 trillion tons of particles thought to be floating on the ocean surface. Before we can make any progress on curbing this pollution, we must first understand how much is concentrated in which places, where exactly it is coming from, and how it is moving around.

For more information listen to this interview done by Kate Nielson from the National Oceanic and Atmospheric Atmosphere:

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The Importance of Sleep

Posted on October 8, 2018 by | 4 comments

Why Do We Need to Sleep?

While not many may know why we need to sleep, most of us do know at some level that sleeping makes us recover the weariness from the previous day or days. Researchers have now shown that sleeping helps us retain information processed in the day time, restore and grow muscles, repair tissues, and even synthesize hormones. However, we still do not know the mechanisms behind much of these known effects of sleep.

A Question Unanswered?

For the past decades, scientist have explored this topic over several aspects. Despite this, it has been difficult to answer this question thoroughly with just one single theory. Instead, sleep patterns can be explained through several sleep theories.

Theories of Sleep

Inactivity theory

One of the earliest theories for sleep, which bases its idea from animal evolution theory.  The theory suggests that inactivity at night serves as a survival function that would keep them out of harms’ way. This is especially the case of animals who would rely heavily on their day time visions. These animals would avoid accidents from happening during night times, for example, trespassing into predatory zones. However, this does not explain why some vision-based animals or humans sleep during the day time.

Restorative Theories

A long held believe is that sleep in some way restores what is lost in the body while we were awake. Sleep provides an opportunity for our body to repair and rejuvenate itself. It is shown that for animals that are completely deprived of sleep loses all immune functions and die within a couple of weeks. This result further supports that some of the major restorative functions like the repair of muscles, protein synthesis, and growth hormone release only occur during sleep.

On its brain and cognitive aspect, the neurons in our brain produces a type of by-product in our brain called adenosine. The build up of these adenosine is thought to be one contributing factor for why we get tired and drowsy. This reaction in our brain is thought to promote the drowsiness while we are awake. When we sleep, our brain has a chance to clear the adenosine from our neuro-system; and when we have enough sleep and wake up, we would feel more alerted with low level of adenosine in the brain.

 Environmental-Cue Theory

This theory involves the internal clock of your body, where the body is in sync with certain cues in the environment. The different light intensities that you receive during day and night are the cues that makes you feel awake or drowsy.For example, light signals received through your eyes transmit a neuro signal to a special area of your brain that it is daytime. This area of the brain helps align your body clock with periods of the day and night. Your body releases chemicals in a daily rhythm, which your body clock controls. When it gets dark, your body releases a hormone called melatonin, which signals your body that it’s time to prepare for sleep, and it helps you feel drowsy. Exposure to bright artificial light (TV screen, computer screen, cell phone etc.) in the late evening can disrupt this process, making it hard to fall asleep. As the sun rises, your body releases a hormone called the cortisol, which naturally prepares your body to wake up.

source: Division of Sleep Medicine at Harvard Medical School

Recommended hours of sleep for each age group:

The amount of sleep you need each day will change over the course of your life, but irregular sleep habits and long-term sleep loss will affect your health in the long run. Certain medical conditions are associated with sleep disorder or deficiency . For example:

  • high blood pressure
  • attention-deficit hyperactivity disorder (ADHD)
  • heart failure
  • obesity

Hence, it is necessary to maintain a healthy sleep pattern.  Although sleep needs vary from person to person, the chart below shows general recommendations for different age groups:

source: National Sleep Foundation

The goal of learning sleep patterns is to better understand the importance of sleeps and enjoy its health benefits. Hope everyone can get enough sleep, because it is vital for us in the future. If you have any sleep theories that you would like to share or anything you just want to share, please comment below!

By: Robin Yuyang Wei

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Does Not Wearing Glasses Mean Contact Lenses for Life?

Posted on October 8, 2018 by | 5 comments

“Why don’t you try contact lenses,” my optometrist offered when I told him I hated my glasses. This is a more common situation than not. I hated spending $200 on glasses each time I wanted to change my style, which is already on the lower end of the price range. Similarly, getting contacts would mean spending up to $1200 a year! Thus, are contact lenses the only solution to glasses?

NO!

A pair of stylish glasses.                                        Credit: Max Pixel

I am sure you have heard of the term myopia and presbyopia or even astigmatism. These are all different types of refractive errors; a condition where the shape of your eye does not bend light properly. With the introduction of refractive surgery, the eye care scene grew drastically with new methods to correct refractive errors through changing the eye’s structures.

Where to Start?

Like any medical procedure, you will arrive for your initial consultation. Your visit will likely begin with the careful investigation of your medical history and countless tests to assess your eye. Then your doctor will discuss the different procedures you are a candidate for. Two of these are LASIK and PRK.

What is LASIK?

Laser-assisted in situ keratomileusis or more commonly known as LASIK, is the most well-known refractive surgery technique.  By using a laser, ophthalmologists form a thin flap in the cornea – a transparent dome covering the outermost layer of the eye – making the removal of a specific amount of corneal tissue possible, before refolding the flap into its original position. This alters the eye’s ability to focus light.

The basic steps on the LASIK procedure.   Credit: Andrearchy LASIK

 

What is PRK?

Do you enjoy sports or just have a very active lifestyle in general? If so, another type of refractive surgery called photorefractive keratectomy (PRK) is perfect for you. In contrast to LASIK, where instead of creating a corneal flap that can become dislodged with intense movement, the doctor will remove the corneal epithelial, which will allow a laser to reshape the deeper cornea.

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Am I Free From Corrective Lenses Now?

It would be pointless if your surgery does not improve your eyesight at all. That’s money down the drain! With any of the procedures, most people end up with 20/40 vision or better. Thus, you can leave your fashionable glasses at home!

Snellen chart to help determine visual acuity.
Credit: Wikimedia Commons

Laser Correction Sounds Exciting, but Scary!

Unfortunately, there are inherent risks and potential side effects. Over time your eyesight will deteriorate and you might one day need glasses again to see properly. As for the immediate side effects of surgery, there is the rare chance of going blind, but in the hands of an expert surgeon the probability is 1 in 5 million. Instead, the possibility of chronic dry eyes is more worrisome. Thus, as you begin your journey remember to save up some money in advance for artificial tears!

By: Jodie Xie

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