College students are closely related to energy drinks. Every night we see students with serious faces, laptops, and 5 hour energies. It seems quite useful. What happens after drinking 5 hour energy? Are there side effects?

First, in general, we know energy drinks contain plenty  of caffeine, sugar, and other chemicals. And we are scared by sensational news like Caffeinated Drink Cited in Reports of 13 Deaths. And we continue to drink and get good grades. What is really going on??????

This study conducted by Marczinski Cecile raises meaningful points. “Participants (n=14) completed a three-session study where they received the energy shot, a placebo control, and no drink. Following dose administration, participants completed subjective Profile of Mood States ratings hourly for 6 hours. Participants also repeatedly completed a behavioral control task (the cued go/no-go task) and provided blood pressure and pulse rate readings at each hour. The results turns out that consumption of the energy shot did improve subjective state, as measured by increased ratings of vigor and decreased ratings of fatigue. However, the energy shot did not alter objective performance, which worsened over time. Importantly, the energy shot elevated both systolic and diastolic blood pressure.”

The study is designed perfectly. The double blinded trial with placebo control shows the most direct effects of the energy drink. However, the sample size of 14 is too small to rule out the possibility of happening by chance. So I find another study conducted by David Apotov to further confirm the results.

David predicts that the energy drinks will have effects on blood pressure, heart rate, heart rhythm irregularity, and brain activity. Involved more than 100 participants, David also conducted double blinded trial with placebo control, and he got the following results.

The charts are quite clear. With no doubts,

the regular 5- Hour Energy drink showed a trend towards a significant increase in systolic blood pressure and  a trend towards a significant increase in heart rhythm irregularity energy drinks do something to hour body which may be potential risks of our health. The companies always claims that a regular amount will not hurt. However, who can define regular for everyone. And with true stories like this one: Anais Fournier, 14-Year-Old Girl, Dies After Drinking 2 Energy Drink. We have to reconsider should we continue to drink energy drinks.

Using the risk measurement method in Andrew’s class, we may get the answer that it is less possible to die from energy drinks than marry Kim Kardashian. However, health problems can be progressive. It is different from car crash. It is true that only 1 in a million people die from energy drinks, but if we count the number of people who have bad body reaction after drinking five our energy, will that be 9 in 10? At least people will get dizzy after more than 20 hours awake.

As for my personal opinion. I do not recommend energy drinks. First, there must be some side effects, and I think everyone knows that. But humans always assume themselves are the lucky ones, so they overlook those implicit potential risk to their health. And second,  no matter what is inside the little bottle, it didn’t give you real energy. 5 year energy only stimulates you to stay up and consume your own energy. Where the extra energy comes from? Can we avoid making up for overconsumption of our own energy? Most of us can easily get the answers. But ignores them and keep hurting our own bodies. Stop that, try to be responsible to your health!!

As a freshman at penn state, I always find myself overwhelming and desire more time. Da Vinci sleep schedule (also called polyphasic sleep schedule, which means sleeping multiple short times a day) is a concept that may help. So I research it and get the following results.

According to business insider, “Rumors credit the success of various famous thinkers, like Leonardo Da Vinci, Thomas Edison, and Nikola Tesla, to polyphasic sleep cycles. The first well-documented sleep dissident, however, was architect, inventor, and philosopher Buckminster Fuller. Fuller experimented with polyphasic sleep throughout the mid-1900s and supposedly coined the Dymaxion sleep schedule. The Dymaxion requires 30-minute naps every six hours, for a total of two hours of sleep per day. In his book, “BuckyWorks,” J. Baldwin writes that Fuller achieved enormous success with his unusual sleeping habits, and his ability to fall asleep within 30 seconds wowed people.

One theory supporting these alternate sleep schedules suggests that human evolution favored polyphasic sleep. A 2007 report from the Journal of Sleep Research found that the majority of animals sleep on polyphasic schedules, and they theorize humans probably wouldn’t have evolved differently.”

The video above is a study performed by Stampi. His participant lived in a polyphasic sleep schedule for 49 days, and he successfully saved 5 hours a day with no obvious side effect observed.

A field study on 99 sailors on a ship gives reliable fact. “Most sailors spontaneously adopted multiple nap sleep-wake schedules and adapted without major difficulties to such polyphasic patterns,” the researchers indicate, “Race performance correlated negatively and significantly with mean sleep episode period and total sleep time. Best performance results were obtained by those sleeping for periods of between 20 min and 1 h and for a total of 4.5 to 5.5h of sleep per day.” Finally, the researchers conclude polyphasic sleep a “promising and feasible schedule.”

However, I found it is really difficult, nearly unrealistic to switch to a polyphasic schedule.  In the last month, I tried my own polyphasic sleep schedule to save time. I sleep 4 to 6 periods a day, and the total sleep time is roughly 4 hours a day for 19 days. Some realistic problems happen during the time. First, it is extremely difficult to wake up, and sometimes I cannot hear the alarming. Second, after each nap, I can focus only in a short time, after an hour I cannot focus well and start looking forward to next sleeping period. Third, after some events, like sport exercise, it is not that easy to follow the schedule, because I am too excited to sleep. And during the process, side effects on me are obvious. I got a sore waist and an aching back. The back pain is very serious and I cannot work or sit. I have to lay down for a while to relieve it. And I feel despondent all day, cannot take interests in anything. One interesting thing that I want to mention is that, in the last 3 days of my polyphasic sleep experience, I do not set alarms to wake me up. And the result is that I still sleep 4 to 6 periods a day, but the total sleep time rises to 12 hours, and even more. But surprisingly, I still feel tired and despondent all day, and after that 3 days, I gave up.

In fact, no study has been done to show long term impacts of polyphasic sleep. As for my experience, I don’t think polyphasic sleep is a wise choice. It does nothing to me but disorder my biological clock. I hope further study can give us a definite answer. Nullify the theory or give us a science-tested feasible schedule.

Stampi. C (1989). Polyphasic sleep strategies improve prolonged sustained performance: A field study on 99 sailors. Word and Stress, 3 (1), 41-55.

Bottle juice is increasingly popular today. People in our generations will choose to buy a bottle of orange juice rather than peel an orange. Even if juice culture is prevalent, and advertisement contains words like healthy, fresh, 100% seem plausible, can juice fully replace fruit. Here comes some opinions of professional nutritionist.

Nutritionist  Marisa Moore claims that juice can be counted as a kind of serving of fruit. However, it pales because of the loss of fiber content and satiety. Dominique Adair raises the points that bottled juice sometimes contain additional artificial sugar and other ingredients and there is no much nutrition at all. Dr. Kelly Traver says that liquid calories are not as filling as calories from solid food, so you can easily go over your calorie threshold when you drink fruit juice.

Summarized their points, three things cause juice not a good substitute, removal of fiber, additional ingredients, and more calories. So let’s analyze what causes this loss.

I am very familiar with bottled juice industry because my cousin works for a juice company. So I would analyze the nutrition of juice compared to fruit from the perspective of producing process.

First, I have to clarify the points that we are not talking about juice drinks, which contains only 20 or 30 percent of juice in the beverage, we are talking about those with “100% juice label”.

First kind of juice is so called long life juice, a kind of concentrated juice. It can lasts 9 to 12 months and are cheapest juice. The sanitation method is classic and simple—heating. The juice is heating to 135 degree. And then water is extracted from the juice and the concentrated juice in preserved for reconstitution (add the water and sugar back). In the heating process the juice loses many nutrition, and in the when the company reconstitute the concentrated juice to bottled juice, they will add additional sugar and other ingredients to guarantee the flavor.

The other kind is chilled juice, which adopts the pasteurization method (like most milk). This methods do preserve most nutrition of juice. But most chilled juice is still concentrated juice, which means they cannot avoid additional sugar and ingredients in the reconstitution process.

The final kind is chilled juice adopted the High Pressure Processing (HPP) method. The most expensive way, and of course the best way. It preserve all the nutrition, and it is not concentrated.

Daillyburn.com gives the following explanation.

Similar to standard pasteurization methods that use heat, HPP neutralizes molecules that cause juice to spoil faster. “Pressure doesn’t damage the product,” says Professor V.M. Balasubramaniam of the Food Science and Technology Department at Ohio State University, explaining that HPP is especially effective in retaining the nutrients, flavor or texture of a product. Dr. Dallas Hoover, Professor of Food Science at University of Delaware and a spokesperson at the Institute of Food Technologists, agrees. “It really doesn’t break bonds or compounds,” he says of HPP, noting that antioxidants and vitamin C will not be significantly reduced.

According to Balasubramaniam, HPP has been used in the United States since the mid-90s, when companies began using intense pressure (sometimes up to 120,000 pounds per square inch, or 10 times greater than the pressure at the bottom of the deepest ocean) to preserve guacamole, vegetable purees, meats and seafood. And in the past seven years, juice companies have learned how to harness HPP for their own products.

To conclude, to answer the first question in the title, obviously most nutritionists told us juice cannot fully replace fresh fruit, but they also admit it is a kind of serving of fruit. So if we want to buy such a serving of fruit, check the label, and determine which kind of juice it is. Without doubt, you have to pay more money for nutrition. HPP juice is 5 to 6 times more expensive than the traditional long life juice. Make your choice.

Last week, my friends and I shared our first impressions of each other in an afternoon tea talk. I was surprised that their comments are quite accurate. And they told me one of their major judging method is my social network page. So I was wondering, does what we you say in social network really indicate who we are?

According to Scientific American, Dr. Pennebaker gives a logical potential explanation.

“It is how an author expresses his or her thoughts that reveals character, asserts social psychologist James W. Pennebaker of the University of Texas at Austin. When people try to present themselves a certain way, they tend to select what they think are appropriate nouns and verbs, but they are unlikely to control their use of articles and pronouns. These small words create the style of a text, which is less subject to conscious manipulation.

Pennebaker’s statistical analyses have shown that these small words may hint at the healing progress of patients and give us insight into the personalities and changing ideals of public figures, from political candidates to terrorists. “Virtually no one in psychology has realized that low-level words can give clues to large-scale behaviors,” says Pennebaker.

A STUDY performed by Karolina S further confirms the conclusion. The researchers hypothesized that “the language used by liberals emphasizes their perception of uniqueness, contains more swear words, more anxiety-related words and more feeling-related words than conservatives’ language. Conversely, we predicted that the language of conservatives emphasizes group membership and contains more references to achievement and religion than liberal language.” Then they analyzed more than 10,000 followers of 3 Democratic Party Twitter accounts and 3 Republican Party Twitter accounts. And concluded that twitter words do relate to people’s personalities and offline behaviors.

The number of participants involved in the study is big enough, so it is unlikely to be happen by chance. It seems like that we get really strong evidence to the original hypothesis. However, there are some potential problems that I concern. First, twitter language sometimes do not express one’s own thoughts. Since twitter is an open platform that everyone can read your word, people sometimes tend to pretend a certain figure in twitter, especially on political issues. Absolutely apolitical person like my sister would say something quite Democratic to raise awareness and gather likes in her Facebook page. The Crack gives The 7 Most Obnoxious Fake Personalities on the Internet. I just wonder whether this will be a third variable that affect the results. Second, for people who use a language as a second language, I think things will change a lot. It is really difficult to erase all the culture clues of a person’s mother language. And for language speaker that are less proficient, conveying a right sentence is far more important, they don’t care about the word they use.

To conclude, no matter how much a person pretend, he or she cannot say something that they don’t know. Thus, at least the social network page shows a person’s knowledge specializations and interested domains. And it represents a person’s own ideas or what a person think is good idea. Back to the beginning, this information definitely will help us know a totally new person. By the way, remember this, when somebody is talking about profound scientific research in Twitter, most possibly he would be a science major student, or, a super-clever SC200 student (all of us), or both.

I am always fascinated by the sweet smile of my younger brother. I watched him born and grown up. His smile can always me feel happy, because I think that is an expression of recognition and love. Is that true? What do infants mean when they smile? Thus I tried to look for researches that can explain that.

Dr. Daniel Messinger is an associate professor of psychology and pediatrics at the University of Miami. In Just the fact baby he divided infants smile into 4 stages.

For infants from 0 to 1 months, they smile instinctively. The action is described as “occur while the baby is drowsy or during REM stages of sleep. And for 1 to 2 months infants, they smile to respond to circumstantial stimulation, auditory stimulation first, and then visual ones. Baby learn to have face to face interaction when they are 4 to 6 months. “They are learning to regulate emotions and the joy may be too intense,” says Dr. Messinger. And when they are 6 to 12 months, babies can make different kinds of smile, and are able to express the extent of their joy, and babies can sophisticatedly use smiling as a regular communication method.

“Some research shows that they smile most often as they’re falling asleep and waking up,” says Alan Fogel, Ph.D., professor of psychology at the University of Utah in Salt Lake City and author of Infancy: Infant, Family and Society. “Those times are probably inherently pleasurable for babies, and their good feelings seem to create a smile.” (Cited from Parent)

From the two studies mentioned above, It seems like that smiling of babies is rather a spontaneous action or a method to express joy in communication. However, the latest study shows that actually babies smile for some purposes. They always expect you to smile back to them.

According to the study published on Plos, Infants Time Their Smiles to Make Their Moms Smile, and they try to minimize the time they smile and maximize the time their mother do.

“Thirteen infant-mother dyads were observed in weekly face-to-face interactions between the ages of 4 and 17 weeks [8]. Mothers provided written informed consent, and the Purdue University Institutional Review Board approved all procedures. For each of the 13 dyads we computed the probability of 4 hypothetical goals separately for each agent (mother and infant): (1) maximize the time of mother smiling / infant smiling (simultaneous smiling), (2) maximize the time of mother smiling / infant not smiling, (3) maximize the time of mother not smiling / infant smiling, and (4) maximize the time of mother not smiling / infant not smiling. The basic logic of how we computed these probabilities follows the four steps described in the introduction. For instance, in the case of determining the probability of each goal for the infant, we perform the following steps: (1) fit a predictive model of mother’s smiling behavior, (2) hypothesize a particular goal for the infant, (3) compute the optimal smile timing for the infant to realize that goal as well as possible, and (4) determine how well the optimal smile timing fits the empirically observed smile timing. “

And the results are indicated by the figure below. Babies want their mother to smile, but not themselves, when their mothers expect mutual smiling.

However, the most interesting part of the study is that to further validate the results, the researchers designed a sophisticated child-like robot, named Diego-San, simulating face to face interaction with adults. And the robots smile for a period of 3 minutes following the control strategies below:

“1- Infant: The robot smiled using the control policy synthesized from the inverse optimal control analysis of infant smile behavior described in the previous section.

2- Replay: The robot smiles were locked to the timing of the smiles generated during the session with the previous participant using the Infant controller. Notably, there was no contingency between the participant’s smiling and Diego-San’s smiling.

3- Mirror: In this condition Diego-San always matched his smile to that of the participant, as if he were a “smile mirror”.

4 Infant Plus: The smile timing of this controller was identical to Infant with the modification that Diego-San was more likely to modulate his expression to be the same as the participant (elevated probability of matching of 50% per second). This controller was designed to test the effect on the participants of increasing the contingency of the robot’s smiling to the participants’ smiling (as compared to the Infant controller).”

The results come out that “the robot maximized the amount of adult-only smiling just as infants had maximized mother-only smiling”, which confirms the original hypothesis.

The study is convincing. Control theory methods are applied, and the mathematical analysis is rigorous. But the most interesting part of the study, the robot simulation part, has many uncertain things. I would question the effectiveness of the robot. All human simulation designs are based on what we have already know. If we don’t know when and why an infant smile, how could we design a program to simulate his or her reactions. Even if we assume the hypothesis is right, and perform the robot simulation for a probability test, I don’t think there is a computer program that can fully replace a human brain. However, I think the robot-human interaction program is a good try, and if one day there is a perfect copy of human brain appeared in computer, which means we digitalize human brains, it is not far from Artificial Intelligence.

People love and hate spicy food. Those who love it, regard food without chilli as tasteless; when those who hate it, choose to stay hungry rather than eating and crying in the same time. Today, I am going to talk about the effect to our body of eating spicy food.

Long time ago people have noticed the question, Published in September 21st, 1983 on the New York Times, Jane Brody analyzed the effects of spicy seasonings on human body. Jane verified capsicum peppers’ effect of stimulating appetite, and pointed out capsicum peppers contain large amount of Vitamin C, Vitamin A, potassium and some iron and protein. She finally described spicy seasonings as “a tastebud- stimulating alternative to salt, the abuse of which can increase the risk of developing high blood pressure.”

However, the latest research performed by Jun lv and Lu qi, professors at Harvard School of Public Health, indicated that a daily habit of eating spicy food is actually good for our health. Their research was finally published in the British Medical Journal [Jun Lv et al, Consumption of spicy foods and total and cause specific mortality: population based cohort study]”

Scientific American summarizes the study perfectly, “ The researchers enrolled nearly half a million Chinese volunteers, aged 30 to 79. They quizzed them on their affinity for fiery foods, and followed each study subject for an average of seven years. During that time, more than 20,000 of the subjects died. But after controlling for factors like smoking history and income, the scientists found that the risk of death was 10 percent lower in those who ate spicy food a couple times a week, compared with those who abstained. And daily chili eaters, like Lu, had a 14 percent lower risk of dying. That figure held true for both men and women. And yes, while it is a relatively modest effect, Lu says to keep in mind: we’re just talking about chilies here. “It’s not medicine.”

Now, let’s analyze the research. Obviously, we can rule out reverse causation easily. The number of participants is big enough, and they are random, so it is not possible that the difference happens by chance. The evidence is quite strong. But the researchers only give very weak “potential mechanisms”, which includes “the bioaccessibility and bioavailability of bioactive ingredients and nutrients of spicy foods”. Thus we cannot conclude there is a causation, and I strongly think that there is a third variable that influenced the result.

The research was done in my home country China, and I knew that Chinese doctors will always warn their patients not eating spicy food when they are sick. And in China, rather than antibiotic medicine, people are more likely to have Chinese medicine which a mixture of extractions from different kinds of plants. Because many ingredients of Chinese Medicine have a conflict with capsicum pepper.  (we say eating the medicine and pepper together breaks of the harmony of Qi in body). And for people who get sick really often, it may change his or her eating habit. More than that, it is not rare that when people stay up to work late, or experience a hangover, they will not eat spicy food. Therefore, I think it may be that people who do not eat spicy food originally have a low resistance to illness or have bad living styles, so people who do eat spicy food often are originally not as healthy as those who eat spicy food daily, which caused the difference of their longevity.

They study is interesting and shows strong correlation. However, researchers cannot explain the mechanism and there is potential third variable effect. In fact, different nations have different eating cultures, and the eating habits of people in different nations, races, ages change a lot. Deliberately change your eating habits may not benefit as expected. The funny fact is that many friends tell me that they will rather die than eating spicy food every day, because they cannot stand the stimulation. But for people who are able to stand spicy seasonings, add more spicy food to your recipe will do nothing negative. Just try it, and it may help.

In hot summer, mosquitos bother many people every night, leading to a poor night’s sleep and swelling and itching of skin. We have heard many stories of mosquitos, such as “ only female mosquitos bite human” and “ mosquitos prefer to bite one blood type rather than the other.” Are these stories true? What is really going on when mosquitos bite humans.

about.com gives a quite informative explanation. It proves that “Only the female mosquito feeds on humans, and she needs a blood meal in order to produce eggs. During a feeding, the female mosquito bites the human skin, and injects saliva. The saliva contains various proteins that prevent the blood from clotting, as well as proteins that keep the blood flowing into the mosquito’s mouth.

Also, about.com attributes the swelling and itching of our skin to allergy. “Many of the mosquito saliva proteins can cause immune reactions, including allergic reactions. Typically, however, most people have a variety of reactions to mosquito bites, and the symptoms change over time, depending on the amount of bites a person received. These reactions can include both immediate and delayed swelling and itching around the bite area. These reactions tend to decrease in frequency after being bitten by mosquitoes over many years. Generally, people with the above described reactions are not diagnosed as being mosquito allergic.”

Thus, that’s what going on inside our body when mosquitos bite us. The following image could help us how to alleviate the swelling.

Sources: http://allergies.about.com/od/insectallergies/a/mosquitoallergy.htm
http://www.dailymail.co.uk/health/article-2998662/Why-people-attract-mosquitoes-Genes-blood-type-beer-drinking-blame.html

Water is necessary for life. Every mother teaches her kid to drink at least 8 glass of water a day. However, does the temperature of water matter? Hot water, warm water, cold water, iced water, how will our bodies react to them?

Born and grown up in China, I am taught to drink warm water. In the theories of Chinese medicine, the food we eat every day not only provides energy, but also regulates the balance of “Yin” and “Yang” in our body, which can be understood as the harmony of our body. Yang food, such as beef, oyster, alcohol beverage, and green onion, usually contains high calories, protein, fat and sodium, and are recommended to eat in winter; on the opposite, Yin food, such as crab, beancurd, and cold drinks, cools and moistens our body. Because modern people drink many cold beverage and beer, thus as for water, people are recommended to drink 50-70 degrees’ water for everyday’s drink. Actually, it is difficult to see iced water in China.

However, there is a totally different scene in the united states. No matter summer or winter, morning or night, in restaurants or at home, Americans drink iced water. In Chinese medical theory, it is horrible. So, does iced work hurt Americans?

Actually, the question is quite controversial in the United States.

Some people believe that iced water is not a problem, because American’s eat most high calories and fat in their meal. So they have extra energy to warm up the cold water.

Some voices claim that drinking iced water harm and give such a explanation, “when cold water hits the stomach, the body is forced to use energy in order to warm up that liquid inside your body to match that of the body’s natural temperature. This robs your body of the energy it needs to properly process what you have ingested. Instead of working to extract all the foods nutrients, your digestive system is instead working on regulating the temperature of the cold drink.”

Source: Why cold water is bad to you

But in Snopes, people call it rumor, and explain that “when you drink cold water, it is entering a system that self regulates to keep its core temperature within about half a degree, or around 37 c (98.6 f). ( For those that are wondering, typical oral temperature readings should be slightly cooler at 36.8c (96.2f)). From the time the water first comes into contact with your body, the heat transfer will begin to warm it up, and it will equalize within a few minutes.”

Even though we cannot find a 100% percent right answer for the question, we can choose the way that suit ourselves best. Asian students drinking warm water their whole life do not need to force themselves to drink iced water, and American student do not have to force them to drink warm water for ant unclear health reason. The truth is that if our bodies feel good, that is good. Just choose the way you body says the best.

Hello, everyone in the SC200 class. My name is Yang Siyuan, and I am from China. I am excited to learn and discuss interesting science with you guys.
I did not choose a science major because that is not my interest. Since middle school time, I feel boring, exhausted, and sleepy when learning chemistry and biology(physics is Ok). However, I like to learn the development and controvesy of science, know interesting science facts, and link science with everyday life (I succeed only a few times due to my poor science knowledge). Thus I choose this course. I really desire to make friends with people with a different culture, plz commented me if you are interested.

Some interesting facts I think related to this course.