It is starting to be that time of year at Penn State when everyone is getting sick. Not a minute goes by in a lecture hall without hearing someone coughing or blowing their nose. But why is everyone getting sick at the same time? And how? Also, what are ways we can prevent this?

First, why do people get sick? People get sick when their immune system is weakened. This occurs when germs that contain the cold/flu virus get into our system. According to the U.S. National Library of Medicine; when something infects our body- like viruses that causes the common cold- our body recognizes the antigens. Antigens are found on the surface of these cells, and our immune system recognizes that these are unfamiliar to our body. This then causes the immune system to react. The U.S. National Library of Medicine cites the first line of defense of the immune system- the innate/nonspecific immunity. The innate/nonspecific immunity includes coughing, tears, mucus, skin, fevers and stomach acid. This is the immune systems first line of defense as it is the body’s attempt to prevent antigens from further breaching one’s body. This causes what we think of as symptoms when we get a cold. A runny/stuffy nose, a cough, or fever. It causes what we constantly hear during lectures, people constantly coughing or blowing their nose. It’s the immune system’s first line of defense to these viruses entering our body.

But doesn’t it seem like everyone is getting sick at the same time? When I first got to school, I was in good health and felt fine. But then around mid-September is when I started to feel a cold coming on and when I began to notice the constant coughing occurring in classrooms. It seems that everyone at Penn State gets sick at the same time. When thinking about this, I thought of some common factors that affects every student: lack of sleep and stress-  these are both common factors that at one time or another affects students at Penn State. But how do they effect our immune system and make all Penn State students seem to get sick at the same time?

College students face a lot of stress. We all know it. There are weeks where you have multiple tests in a row on top of other organizations you’re involved in, and a job, and a social life. At times its overwhelming. In a meta-analysis, performed by Suzanne C. Segerstrom and Gregory E. Miller, of over 300 studies there is a link between stress and the strength of the immune system. Segerstrom and Miller categorized the type of stress that most plagues college students as brief naturalistic stressors. This meta-analysis found that these brief naturalistic stressors affect the student’s immune system by decreasing the number of natural killer cells which are used to fight off viruses- like the common cold. It was also consistent in the study that long term stress caused the reduction in function of a person’s immune system. This could explain why everyone at Penn State seems to get sick at the same time. It all seems to happen at the first rounds of exams are approaching- which also means lots of stress. However, I know that I do not seem to every fully recover from being sick until I go home for Thanksgiving Break or Christmas Break. This relates to the fact that the longer a person is stressed- the more of a negative impact on their immune system. The fact that everyone at Penn State gets sick around the same time can be related to their stress levels that are having a negative impact on their immune system.

Another of my proposed common factors of all students that could lead all students to getting sick at the same time was lack of sleep. As college students, we do not get the recommended eight to nine hours of sleep every night. It’s a good night if we get six hours. Why so much lack of sleep? Between studying and self inflicted lack of sleep- going to parties or binge watching Netflix- students do not get enough sleep on a regular basis. In a study conducted at Carnegie Mellon University, researchers asked a sample of 153 people to self report: length of sleep, quality of sleep, and how rested they felt. The researchers put nasal drops containing the flu virus into the participants. The study then found that those with self reported poor sleep efficiency were more likely to contract the virus than other participants- it also controlled for multiple factors like BMI, age, race, sec, and other factors. However, there are no mechanism found in this experiment. However, from the class example of smoking and lung cancer- where there is still no known biological mechanism. It is thought that lack of sleep hurts your immune system as there are not as many natural killer cells- similar to the effect of stress on the immune system. And there is an increase of pro-inflammatory cytokines which is one of the producers of fever- a symptom of the common cold. As with the example of smoking and lung cancer, there are enough studies that link the immune system and quality of sleep together that one believes that they are connected even though we do not know the biological mechanism. I would say that it is safe to assume that if you want to maintain a healthy immune system, you would get an efficient and minimum of 8 hours of sleep, especially if you wanted to avoid the Penn State plague!

So what does this mean? It means that we can infer that the reason all Penn State students are getting sick at the same time is because of constant stress from exams and lack of sleep from being college students. This is my own conclusion made from personal experience (anecdote observation) but can also be proved through science. The effects of stress and sleep on student’s immune systems can be done through a meta-analysis of studies. Scientist conducted these studies for stress and concluded that the stress from tests has a negative impact on your immune system. I think there should be a meta-analysis of studies for lack of sleep on students as well. Also, there are enough students throughout the world that I propose a large sample study be conducted. I propose that it would be observational, participants would answer survey questions about their amount of sleep and their level of course work and also track the amount of times that they have gotten sick in the year. This study would be observational- therefore we would not be able to find a mechanism. However, like the observational studies done on the effect of smoking on people through their life time- this could potentially produce results that help us understand why students are so prone to things like ‘The Penn State Plague’ and why it effects the campus as a whole at the same times. I think that this is important because as someone who is year after year affected by the Penn State plague, I want to prevent it. Also, I think that everyone would benefit if we are not constantly hearing the coughing and sneezing throughout a lecture hall every 2 seconds.

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A new study proposes that people who smoke marijuana daily have a lower percentage of body fat. The study observed a sample of adults 18-26 years old and observed them again six years later. In these observations, the researchers measured BMIs and amount of marijuana used. The study concludes women who smoked marijuana everyday had a 3.1% lower BMI and men who smoked everyday had a 2.7% lower BMI in contrast to those who did not smoke everyday.

Does daily marijuana use help weight loss?

In class we learned that correlation is not causation. Just because the study shows a correlation between smoking marijuana everyday and a lower body fat percentage- does not mean that they are related. The study does not cite any mechanism that result in marijuana causing a lower body fat percentage. However, the study does control for confounding/third variables that would effect the correlation. According to the study, they controlled for diet, exercise, and alcohol drinking habits.

The study took place over a period of time, six years. As we learned in class this helps reduce the factor of random chance in the study. However, since the study was observational random chance cannot be entirely ruled out. Also, the study shows correlation between daily marijuana smoking and lower BMI’s but this can be explained different ways. Direct causality, a person smokes marijuana everyday this then causes them to have a lower BMI. Reverse causality, there is something about have a lower BMI that causes a person to smoke marijuana everyday. Confounding or third variables, smoking marijuana daily and lower BMI are not causally related but effected by something else. For example income: a person smokes a lot of marijuana this then causes them to have little extra money which in turns causes them to eat less and have a lower BMI. Another scenario is socioeconomic factor:  people from lower income areas have lower BMIs as they have less food because lower income areas are more at risk for gang activity they have a larger likeliness of being exposed to marijuana and smoking everyday. Another third/confounding variable is culture: people who grow up in a hippie lifestyle home are more likely to smoke as it is apart of the culture, they are also more likely to have lower BMI’s because they are more likely to be vegetarians as both are norms of the culture. Since there is no mechanism found in the study- any of these correlations could be feasible to explain the relationship between lower BMIs and smoking marijuana daily.

Does smoking marijuana daily lead to weight loss?

This study involved a lot of the concepts that we have spoken about in class. It was a longitudinal study. We talked about how this reduces random chance- but does not rule it out. The study’s outcome shows a link between marijuana and BMI but there is not evidence for a mechanism that would explain how marijuana effects BMI therefor we cannot be sure it is marijuana causing the lower BMI, the lower BMI causing daily marijuana smoking, or another confounding variable causing both. The study controlled for factors that may effect the outcome- this increases validity of the results. However, because this is a correlation (as we learned in class) there are still options for reverse causality and random chance to explain why there is a link. Overall, I would not recommend smoking marijuana everyday as a weight loss tactic as there is not found mechanism.

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The ‘Five Second Rule’ is a rule that many people grew up following. It is the idea that if one drops food on the ground it is still safe to eat if it is picked up within five seconds of dropping it because there would not have been enough time for bacteria to transfer on to the food. Researchers at Rutgers have investigated the validity of this rule.

Should you follow the 5 second rule?

The researchers investigated the Five Second Rule by using four types of food (watermelon, bread, bread and butter, and gummy candy) dropped on four different surfaces (stainless steel, tile, wood, and carpet). According to the study, they used the bacteria Enterobacter aerogenes.It does not cause disease but is closely related to Salmonella. The study also varied the amount of time that the food was dropped on the surface. The varied times were one second, five seconds, 30 seconds, and 300 seconds.

Donald Schaffner, the conductor of the experiment, cites moisture as one of the factors that most affected the transfer of bacteria from the different surfaces on to the different foods. This is seen in watermelon, which had the highest amount of bacteria transfer, and gummy candy, which had the lowest amount of bacteria transfer. Why is this? Bacteria move with the help of flagella or pilli. Flagella is a long tail structure that moves around to propel the bacteria and pilli cover the bacteria and pull the bacteria forward. The presence of moisture aids the movement of bacteria. Another factor was the length of contact, the longer the food was left on the surface the more contaminated it was with bacteria. The surface that the food ‘fell’ on in the experiment was another factor that affected amount of bacteria. According to Schaffner, carpet had a lower amount of bacteria transferred then tile and stainless steel, and wood varied.

Flagella, one method that bacteria uses in order to move.

The results of this study are based off of 20 trials of 128 scenarios. In class, we learned that not all data is equal. Data has a stronger inference when it is a properly designed experiment and has an even stronger inference when it is a good experiment with good field observation or evidence of mechanism. This experiment has strong inference because there are multiple trials. Since there are multiple trials, if they all yield similar results this proves the validity of the outcomes. This experiment had 20 trials making the results of the experiment valid as it was a fairly designed experiment. The repeat of trials helps reduce random chance, although it is always still a factor.

I know that I drop food all of the time and then debate whether it is safe to eat or not. This article proves that depending on the food or surface your food may be safe to eat if it is picked up in a short amount of time. However, if your food has moisture and has fallen on carpet or stainless steel- it is safer to not eat the food. If it is a gummy candy falling on a carpet- it is pretty safe to eat. However, this experiment makes me think about the number of bacteria that can be on your food when you drop it. Five second rule or not- its always better to be safe than sorry with food poisoning.

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For more information on how bacteria move click here.

The use of embryonic stem cells has been a topic of hot debate over the years. It is controversial because in order to retrieve the embryonic stem cells- the embryo is destroyed. Nonetheless, research into the use of embryonic stem cells has continued over the years. This research has continued because of the potential of embryonic stem cells as they have the ability to become any cell in the human body. As a result of this ability, embryonic stem cells are being researched for their potential in curing cancer, spinal cord injury, diabetes, and other diseases/injuries that do not yet have a cure.

Kreck Medical Center of USC is one of the many researchers in the field of embryonic stem cells. Kreck recently performed a study in which inserted embryonic stem cells into a paralyzed man. This man has since regained motion in his hands and arms. According to the study, the embryonic stem cells are transformed into spinal and brain cord cells, oligodendrocyte progenitor. The function of oligodendrocyte progenitor cells is to support nerve cells. In the lab, the dose of these cells was seen to improve various functions that are important to nerve impulse. This improvement is what helped the paralyzed man regain function in his hands and arms.

Dr. Lui, the head of the research team, showing the patient’s spinal cord injury.

This study is important because there is no known way to cure a spinal cord. Once an accident that injures one’s spinal cord happens- that person is paralyzed for life. This incidence of a man regaining function in his arms and hands- as he was paralyzed from the neck down- is a huge step in finding a way to heal spinal cord injuries. Gaining this function is the difference between living a life entirely dependent on a caregiver and being able to be independent and do basic functions of day to day life. This man was just 21 years old. Imagine being 21 years old and going from being completely independent to needed a caregiver to do something as basic as comb your hair. This study has made a huge impact in this man’s life after injury.

Over the summer I interned for the not-for-profit organization, Paralyzed Veterans of America. During my internship I went to the National Veteran’s Wheelchair Games. At these Games, I interacted with many paralyzed Veterans. These interactions have made me realize how much we take for granted. For a lot of these Veterans, they have to depend on a caregiver to basic things like eat- an action able bodied people do not think twice about. When I saw this study it resonated with me as I thought of how many lives this could improve. This study is the first step into continuing embryonic stem cell research and advancing to completely regaining function in one’s whole body. I’m excited to see in the future the advance the science community makes in healing spinal cord injuries. Also, to see embryonic stem cells at work healing the spinal cord and whether spinal cord pre-injury and post-injury would look identical or would resemble something else, but is still functioning? The advancements the science community is making with embryonic stem cells is fascinating as there are so many potential benefits that can occur for people who at one time did not have any hope for a cure- just treatments.

Advertisement for the National Veterans Wheelchair Games that I attended and met many paralyzed veterans.

Image Credit:
image one: https://www.sciencedaily.com/releases/2016/09/160907082248.htm
image two: http://www.saltlakecity.va.gov/36th_NVWG_Comes_to_SLC.asp

Link to the study.

Hi everyone, my name is Isobel Hoang. I am a sophomore business major from Northern Virginia. I’m taking Science 200 because I needed a science general education course. I choose Science 200 because it’s wide breadth of topics enticed me as it seemed to be more interesting than a class that focused on the specifics of one topic. Science 200 also appealed to me because it is geared towards non-Science majors.

I am not planning on being a Science major because I have never liked science in the past. Growing up, my science teachers never made the subject interesting. The only interesting days in science was when the teacher would play a video. Videos like Bill Nye and the Magic School Bus became the only interesting thing about the subject. In high school, the Science teachers made the class tedious and filled with busy work. This increased my dislike for the subject and my inclination to not be a Science major.

Bill Nye (above) the savior of science in elementary school.

If you are like me, and miss Bill Nye being the only thing about science that you enjoy- then go to this link here. It will take you to Bill Nye’s website where he has videos uploaded. You can take a walk down memory lane and watch some of his recent science experiments.