Groundhog Day 2018: Probability in perspective

Posted on January 30, 2018 by Lana Ruck

This Friday will be the 132nd official Groundhog Day in the United States. Celebrated in Canada, Germany, and the U.S., the holiday derives from a long-standing German-Dutch tradition, which we’ve been officially recording since 1886. The basic idea: if a groundhog emerges from his hole and sees his shadow, winter will last for six more weeks, but if he sees no shadow, an early spring is on the way.

Why are we discussing this arguably adorable tradition on a science blog, you ask? Although there’s much we can learn about the tradition (and lots of lore!), Groundhog Day is our post topic this week because it’s a great way to explore the basic concepts of probability. Scientists use probability theory every day in their research, most notably, to make sure that the phenomena we are studying are not due to random chance. Probabilities can be complex, but even in their simplest form — as is the case with Groundhog Day — the questions we can answer using probability theory are often quite interesting. (more…)

How researchers use sequencing techniques for social science research

Posted on January 23, 2018 by Brittany Hood

Have you ever wondered why or how researchers categorize people into different groups? Of course, there are specific types of groups you might first think of, such as differentiating people by race, gender, income level, marital status, and education. However, there are a variety of other types of groups that researchers might find interesting that you may not be aware of. For instance, some researchers are interested in studying people based on patterns of their activities over a span of time. An example of this would be if a researcher was interested in studying the differences between types of offenders. For example, each time they were: 1) expelled or suspended from school, 2) arrested, 3) convicted, and 4) incarcerated. There are other variables a researcher might also find to be important: periods of 1) homelessness, 2) unemployment, 3) graduation from high school and 4) marriage.

DNA strand comprised of people — DNA strand.

This might seem like a very daunting task: to categorize people based on all the possible sequences of events that happened in their lives. And it is. However, researchers have tried to find more efficient methods of categorizing people into groups. One relatively newer method of determining groups uses a computer program to examine how many different sequences of events across time exist in a sample of subjects. This method is called sequence analysis. Sequence analysis for social science research had its origins in the study of evolutionary patterns and modes of descent of DNA molecules, initially (and still) carried out by biologists. However, social scientists have co-opted this method for social sequence analysis, in which they study patterns of events. The use of this term in this blog post, therefore, refers specifically to identifying patterns of events based on their classification into different categories and the specific ordering of the events. [1] (more…)

GPS: Not just for finding the closest pizza place

Posted on January 16, 2018 by Anna Jessee

A screenshot of a GPS navigation app on a mobile device. The screenshot shows a map of the IU Bloomington campus. — A GPS screenshot from my phone, showing my location as a blue dot at the Geological Sciences building.

How exactly does your “Maps” app know exactly where you are, any time of day? The “little blue dot” on your phone tells you where you are as the result of billions of dollars invested in the Global Positioning System (GPS), a network of 27 satellites currently orbiting the Earth. Each satellite sends microwaves constantly, containing information about their location and the time the wave is sent. Your phone detects these waves with a tiny antenna, and its GPS chip calculates the amount of time it took for the waves to reach it; knowing that the waves travel at nearly the speed of light, it calculates how far away your phone is from the satellite. By doing this using four or more satellites, it displays the “little blue dot” on your screen that moves as you do, a fairly accurate estimate of your phone’s location. Pretty amazing, right? (1) (more…)

When human eyes are needed

Posted on January 9, 2018 by Jennifer Sieben

In a world that looks more and more like a science fiction novel, it can be tempting to assume that a computer program or code can do all your tedious work for you. Algorithms suggest videos you might like to to watch on YouTube, plan your road trips to visit friends, and can even frost a cake you ordered for your sister’s birthday with a picture of her face in the center. It doesn’t seem like a leap of faith to assume they can help make astronomical research easier as well.

It should be simple for an algorithm to sort images of blurry dots. But when those dots are galaxies larger than our own, some of which are previously undetected because of how far away they are, it can be hard to train a computer program. Instead, my collaborators and I must visually inspect hundreds of dots and blobs in our images, trying to see if any of them are worth examining in more detail. (more…)

Working with pyrophoric materials in lab: An intro to preventing explosions

Posted on January 2, 2018 by Josey E. Topolski

Chemistry labs typically contain a number of potential hazards ranging from chemicals to lasers and beyond. Pyrophoric materials are among the most dangerous, as they spontaneously and violently ignite when exposed to mere water, or even air! Dealing with pyrophoric materials safely requires significantly more protection than that offered by traditional safety attire like eye protection and lab coats. As a chemistry doctoral student at Indiana University, I work with pyrophoric materials all the time and I have not once created a catastrophically destructive fireball.

To better understand how can we can prevent pyrophoric disasters, we first need to understand what causes them. Pyrophoric materials ignite spontaneously when exposed to water or air. The probability of this reaction increases exponentially with the amount of exposed surface area, which makes pyrophoric materials in the form of small filings or fine powder particularly risky. Their dramatic reactivity can be traced back to the material’s desire to be oxidized or lose electrons. Many pyrophoric elements are alkali metals, which lie in group one of the periodic table. These metals have one more electron than their preceding, very stable, noble gas which has a stable electron configuration. For example, sodium (Na), an alkali metal, has one more electron than neon (Ne), a noble gas. This lone, unpaired electron is what makes sodium very reactive. (more…)

Business as usual? On scientific progress in the public sphere.

Posted on December 26, 2017 by Lana Ruck

If you’ve ever taken a basic science class, you‘ve probably heard of the scientific method. Maybe you’ve even designed, conducted, and reflected upon your own experiment–inside or outside of the classroom. One thing you may be unfamiliar with, however, is how the millions of experiments done by scientists, students, and citizens get added together into a coherent body of knowledge on a topic. In other words, how does science actually progress? (more…)

The process of science and politics and the risks to education

Posted on December 19, 2017 by Briana K. Whitaker and Chris ChoGlueck

As recently as Thursday of last week, two different versions of a tax reform bill were working their way through a reconciliation committee comprised of House Representatives and Senators. The House version of the tax reform bill had called for changes to the tax code that would have dramatically affected the personal finances of graduate students in the United States. On Friday, Congress released their reconciled version, which removed this change and will likely be voted on today. This cycle of sequential bill releases by both branches of Congress, their subsequent votes, reconciliation, and final vote before passage is a common political process on Capitol Hill. But, how does this political process relate to graduate education and the scientific process more broadly? (more…)

FoREM: Bringing modern research to the physics classroom

Posted on December 12, 2017 by Guest Contributor

The author is ScIU guest writer Corrine Deegan, a graduate student in IU’s Department of Physics.

What do you remember the most from your pre-college physics lessons? Perhaps you learned something about how every action has an equal and opposite reaction, or perhaps you were lucky enough to be shocked by a Van der Graaf generator. Upon discovering that I study physics, most people generally have one of two key responses: they either recount some typically negative story from their high school physics class or insist that anyone who studies physics must be brilliant. For better or worse, these reactions are generally constant across age groups.

While these reactions are generally not positive, it is nearly impossible to blame the students when the traditional teaching methods leave much to be desired. Introductory physics courses are often taught following the same unfortunate series of events: first, we are made to memorize the right equation and then we are confused when the problem is not identical to a homework problem whose solution is already known. In addition, courses at the introductory level must cover the less glamorous fundamentals of the discipline, which admittedly can be somewhat of a bore to anyone expecting the levitating magnets or lasers seen in the media. To improve the perception that physics is boring and/or impossible, we need to connect the basics of the subject to current research and familiar technology. And professors like Dr. Babak Seradjeh are doing just that. (more…)

Two-faced particles can solve a drug delivery dilemma

Posted on December 5, 2017 by Kimberly McCoy

How do you get foreign molecules in the body to fly under the radar of the immune system while at the same time engineer them to interact directly with immune system cells? When designing a drug, scientists walk a fine line between getting the body to notice a drug and not marking it as an invader. Researchers at Indiana University have developed particles that can do both.

A study from this year has shown that a Janus particle — a double-sided nanosphere named after the two-faced Roman God Janus — can split the two jobs between the two sides.

Janus particles are a few hundred times thinner than the thickness of your fingernail, so it’s not surprising that they are difficult to make. How do you preferentially coat only half of a uniform sphere? Imagine adding a dump truck of feathers to a bunch of bouncing soccer balls coated in molasses – the soccer balls would get completely coated with the feathers, the same way sticky particles floating in water get completely coated with a small molecule. If, however, you had a way to pack all of the soccer balls on the floor, so that the feathers couldn’t get to the bottom side, then you could coat half of each ball with the feathers leaving the other side still sticky. (more…)

Criminal offending in mentally ill populations

Posted on November 28, 2017 by Brittany Hood

A word cloud in cold colors of words such as attitude, depression, treatment, worried, therapy, mental health and clinical. — Common words associated with mental illness (CC0 Creative Commons).

There are currently more individuals diagnosed with severe mental illness (SMI) in jails and prisons in the United States than in hospitals [1]. Deinstitutionalization (explained in the next paragraph), changes in sentencing policy, the war against drugs and mass incarceration have all contributed to the dramatic increase in the number of mentally ill who are incarcerated [2]. Severe mental illnesses such as schizophrenia, bipolar disorder, major depressive disorder and borderline personality disorder affect one in five adults at some point in their lives [3]. Of those, approximately three in ten people have interactions with the criminal justice system [4] resulting in one million SMI individuals detained per year [5].

Deinstitutionalization began in 1955, it is the process of replacing long-stay psychiatric hospitals with mental health services for individuals diagnosed with a mental disorder or developmental disability. As a result, individuals were forced to use private mental health services to get treatment. However, not everyone had access to private insurance, and after being forced out of hospitals, with limited access to treatment, many previous patients were forced to live on the street or ended up in jail or prison. (more…)