Monday, September 10, 2018

MD/PhD Research Experience Essay Example

Application for MD/PhD programs requires three essays:
  1. Personal Statement
  2. MD/PhD Essay (a statement of interest specifically for both MD and PhD degrees)
  3. Research Experience Essay (a detailed description of your research experiences)
I published my MD/PhD Essay as an example for students back in 2014 (link above). Hopefully my research essay will also be a helpful example.

My MD/PhD Research Essay

Prompt: Describe your significant research experiences. In your statement, specify your research supervisor's name and affiliation, the duration of the experience, the nature of the problem studied, and your contributions to the project.

1) Toxicology, Ichthyology, and Marine Ecology Lab
Dr. Sandra Diamond (Ph.D., Zoology, North Carolina State University), Assistant Professor, Texas Tech University
January 2011-Present
1a) Antibiotic Toxicology Project (January 2011-May 2012)
My research with Dr. Diamond began with the examination of an antibiotic, Triclosan, that is included in many personal care products. After use, Triclosan is carried through drains to wastewater treatment plants. While some of the Triclosan is purged from waterways, a significant amount escapes and reaches the oceans. There, it is incorporated into the fatty tissue of benthic organisms, where it interferes with calcium signaling. The widespread distribution of Triclosan is beginning to cause humans to acquire significant levels of Triclosan, especially in breast milk. This could generate antibiotic-resistant bacteria, and may even impede calcium signaling in humans. Our goal is to understand the potential dangers of Triclosan in the environment.
I contributed to this project by working closely alongside a graduate student and constructing a literature matrix on how Triclosan behaves in the ocean. I participated in laboratory experiments, collected data, maintained the laboratory, and helped proofread material for presentations.
For my work, I was acknowledged in "The Effects of Triclosan on Reflex Responses and Anti-Predator Behavior in an Estuarine Fish" (Tiffany L. Hopper-Hedrick and Sandra L. Diamond), a poster that my group presented at the Ecological Society of America.
1b) TTU Shark Team (May 2012-December 2012)
Upon completion of the toxicology project, Dr. Diamond hired me onto the TTU Shark Team, a group seeking to establish multi-national management of shark fisheries in the Gulf of Mexico through a deeper understanding of shark ecology. Historically, the oceans have been overexploited due to advances in technology and competition for resources. Because sharks have long generation times, they are particularly vulnerable. We use geographic information systems and statistical analyses to map out seasonal distributions for fourteen species of sharks.
In this group I contributed to the construction of a literature matrix containing over 800 papers to communicate large-scale trends, such as seasonal distributions. This experience has developed my critical reading skills, increased my general understanding of scientific thought, and prepared me to design an experiment of my own.
1c) TTU/Howard Hughes Medical Institute Affiliated Project (May 2012-Present)
After earning designation as a TTU/Howard Hughes Medical Institute Undergraduate Research Scholar in May of 2012, Dr. Diamond gave me the scientific freedom to design and carry out a research project.
The concentration of carbon dioxide in our atmosphere is increasing, causing the pH of the oceans to lower significantly. In addition, ocean fertilization (the mass addition of nitrogen and phosphorus) is causing algal blooms. Because algae use up oxygen, the dramatic increase in algal populations has resulted in the creation of 'dead zones' in which there is little or no oxygen. My research examines the synergistic effects of acidification and hypoxia on Atlantic Croaker.
I am responsible for designing experiments, writing protocols for acceptance by our Animal Care and Use Committee, collecting data, making decisions concerning our budget, communicating with companies to purchase scientific equipment, and writing a technical paper. Five months ago, I was given the responsibility of organizing and training five undergraduates in our lab to maintain our artificial ocean system while Dr. Diamond was in Australia for two semesters. In addition, an undergraduate researcher worked on a sub-assignment under my project.
I have presented my work in this lab at four conferences: Texas Tech University Health Sciences Center Student Research Week, TTU/Howard Hughes Medical Institute Best and the Brightest: Research Forum, The Texas Chapter of the American Fisheries Society, and Texas Tech University Undergraduate Research Conference. Abstracts for this work have been accepted at the Arkansas Chapter of the American Fisheries Society and the 2013 TTU/Howard Hughes Medical Institute Undergraduate Research Forum.
I was also part of a panel of researchers from TTU for Earth Day at North Ridge Elementary School. At this event, I delivered a presentation on Marine Biology and Environmental Sustainability with an emphasis on mantis shrimp and sharks.

2) Plant Evolution and Ecology Lab
Dr. Dylan Schwilk (Ph.D., Ecology and Evolution, Stanford University), Assistant Professor, Texas Tech University
October 2012-Present
2a) TTU/Howard Hughes Medical Institute Affiliated Project (October 2012-Present)
In Dr. Schwilk’s lab, we are pursuing an understanding of tree ecology in the mountain ranges of Texas. The water transporting vessels (xylem) of trees become clogged, much like arteries in humans, in a process known as drought-induced embolism. Although it is impossible for negative pressures to exist in gaseous systems, this is not the case with liquids. Trees rely on extreme negative tension to pull water to heights much greater than those allowed by adhesion, cohesion, or atmospheric pressure. When trees experience drought conditions, the strength of these tensions increases as the amount of water available to them decreases. This makes the pressure within the xylem so low that water starts to boil, and bubbles form within vessels. Once a certain percentage of the xylem within a branch becomes embolized, it is sacrificed by the tree. My project examines the point at which branches are sacrificed in four oak species.
My reasons for joining Dr. Schwilk’s lab are unique. Normally, TTU/HHMI Scholars work in a single lab due to the expected levels of involvement. However, in October of 2012, one of my fellow scholars, Chris, passed away in an automobile accident. Because the TTU/HHMI Scholars are a tight-knit family, I decided to inherit his project and finish it for him. I invited every TTU/HHMI Scholar to participate in completing his project to help us heal as an organization.
My responsibilities in Dr. Schwilk’s lab include writing, modifying, and developing the protocol for an experiment, training undergraduate researchers and delegating scientific tasks, participating in expeditions to the Davis, Guadalupe, and Chisos Mountains, carrying out laboratory experiments, and recruiting new laboratory members.
I led one trip to Davis Mountains with a single non-scientist assistant to gather data.
An abstract for this work has been accepted for the 2013 TTU/Howard Hughes Medical Institute Undergraduate Research Forum, where I will present our findings in honor of Chris’s memory.
For simultaneously working full-time in the Diamond and Schwilk labs, successfully lobbying for Texas Tech University to continue its support of TTU/HHMI, and organizing and training groups of scholars to participate in Chris’ project, I received the Dr. Richard L. Blanton Endowment for Undergraduate Research.

3) Honors Thesis in Physics and Biology
Dr. Micah Green (Ph.D., Chemical Engineering, Massachusetts Institute of Technology), Assistant Professor, Texas Tech University
January 2012-Present
3a) Honors Thesis as part of the TTU Honors College
I received approval in January of 2012 to conduct an Honors Thesis outside of my major on the fine-tuning of four cosmic parameters in phase space. Normally, students are encouraged to pursue topics related to their undergraduate major when conducting an Honors Thesis. However, I was allowed to proceed with a physics-based inquiry, since I had gained competency in physics and cosmology as a result of personal study.
Over the past hundred years, physicists and cosmologists have started to notice that if certain fundamental characteristics of our universe had been anything other than what they are, the evolution of life in our universe would have been impossible. An example of one of these characteristics, called “parameters”, is the gravitational constant. If the force of gravity had been stronger during the big bang, the exploding matter would have re-condensed into a black hole. Alternatively, if gravity had been weaker during the big bang, there would not have been enough attraction between particles for stars to form, resulting in a universe comprised almost entirely of hydrogen and helium. In either case, the evolution of life in our universe would have been impossible. The general consensus of the scientific community at this point is that many parameters are finely tuned, meaning that miniscule variations in their values would render the universe lifeless.
My Honors Thesis is a review of the current scholarly conversation on the fine tuning of the universe. My primary insight concerns the target of fine tuning. Historically, physicists assumed that the universe needed to be fine-tuned for our form of carbon-based life specifically. As an evolutionary biologist, I know that this is not the case. A universe only needs to maintain a stable environment, contain the essential building blocks for complex molecules, and be expansive enough for origin events to be probable. Once an origin event takes place, natural selection could cause those collections of molecules to evolve in any number of directions. Dr. Green and I conclude that our four target parameters display fine tuning, but to a much lesser degree than has traditionally been accepted.
Because this project serves as an interdisciplinary link between biology and physics, I presented my work at GK-12 Building Bridges: Integrating Math, Science and Engineering on the South Plains. I was also invited to participate in a panel on trans-disciplinary research at this conference.
For my work on this project I received the 2013 Honors College Collaborative Learning Award.

Friday, September 7, 2018

Jesus was stabbed in the stomach

Blood mixed with water flowed out of Jesus' spear wound because he was stabbed in the stomach (probably).

We have almost no detailed information on the location of Jesus' spear wound. However, we do know three things:
1. The spear head must enter the "side", which could mean anywhere on the lateral aspect of Jesus' abdomen or torso.
2. Jesus was elevated on a cross, therefore the spear thrust would have been at an upward angle.
3. Blood mixed with water exited the wound.

There are numerous complicated scenarios in which water could have exited through the wound along with blood--most notably a pleural effusion that built up from a previous injury. These scenarios are less likely because they require an additional hypothesis (that one of the previous injuries caused abnormal fluid buildup in one of Jesus' body cavities, and this was later pierced by the spear).

But there are two situations that do not require an additional hypothesis. There are two locations where "water" builds up under normal circumstances--the stomach (Figure 1) and the bladder.

A spear wound to the bladder is so unlikely that it is hardly worth mentioning*.

A spear wound to the stomach is extremely likely (Figure 1). First, a spear wound that entered Jesus' stomach definitely would have been described as a spear wound "to the side". Second, the elevation of Jesus and the upward angle of the thrust favors a stomach wound (Figure 2). Third, Jesus had fluid in his stomach (beyond the normal gastric acid that is always present):

"28After this, Jesus, knowing that all things had already been accomplished, to fulfill the Scripture, *said, “I am thirsty.” 29 A jar full of sour wine was standing there; so they put a sponge full of the sour wine upon a branch of hyssop and brought it up to His mouth. 30 Therefore when Jesus had received the sour wine, He said, “It is finished!” And He bowed His head and gave up His spirit." (John 19:28-30)

Figure 1. Spear thrust to the stomach. Modified from

The stomach wound scenario is so obvious that I cannot fathom how it isn't widely accepted as the leading hypothesis for Jesus' spear wound.

If Jesus had died from previous injuries, there would have been fluid in his stomach, and the spear would have caused that fluid to mix (at least partially) with blood. If Jesus were alive, the same thing would have happened.

In fact, the stomach would have been hard to miss using an upward thrust to the side of an elevated victim. Check out a horizontal cross-section of the upper abdomen (Figure 2). Because the spear was traveling at an upward angle into an elevated victim, the horizontal plane is especially helpful for illustrating what organs would have been in the way of the spear thrust. The primary target (that definitely would have produced blood mixed with water) is the stomach.

Figure 2. Stomach outlined in green. Modified from

Conversely, at an upward angle, a spear thrust would have difficulty passing directly between two ribs (the more vertical the angle, the harder it would be). This isn't to say that a spear thrust couldn't break ribs (it could), it's just less likely than a stomach wound (which wouldn't have needed to either "thread the needle" or break ribs). This is especially true if the spear had a broad head. And again, the scenarios in which "water" is mixed with blood require additional hypotheses for thorax wounds. A stomach wound scenario does not.

A spear wound to the heart would have released SO MUCH blood  that it is unlikely that observers would have been able to appreciate any "water" coming from the wound, even if fluid had built up somewhere (unless it was a very large amount of fluid--which again requires far more mental gymnastics than a simple stomach wound). Observers definitely would have noted the watery appearance of fluid emanating from a stomach wound.

In conclusion, by far the most likely scenario is that Jesus was stabbed in the stomach.

The bladder-wound scenario
*Because Jesus was elevated on the cross, a spear wound thrust upward would have needed to enter Jesus' leg and travel upward to eventually pierce his bladder, and it would have needed to pass through thick bones to do so. This did not happen.

But the stomach is only on one side!
 True. Only wounds to Jesus' left side fit with this scenario. Similar wounds to the right side of Jesus' body would have hit the liver, which would not have resulted in "water" mixed with blood exiting the wound.

What about hitting both the stomach and the heart?
A spear thrust could go all the way through the stomach and then enter the heart. This definitely would have killed Jesus. However, this scenario is less likely than a simple stomach wound.

Thursday, August 30, 2018

The dehydration of Jesus

This is part 3 of a series I'm writing on the crucifixion from a medical perspective. Check out parts 1 and 2 first if you haven't seen them! Part 1, Part 2

For the purposes of this post, let's assume Jesus survived the crucifixion and the spear wound and was laid in the tomb unconscious. Would dehydration ensure death?

A common popular belief is that people can survive no more than three days without water. This belief is far too simplistic. The actual length of time a person can survive without water depends heavily on the ambient temperature and the activity level of the person. For example, someone would absolutely die if they tried to exercise in the desert for three days straight without water. On the other hand, a person lying in bed sleeping in a cool room would almost certainly survive (unless they had some sort of underlying condition, injury, or blood loss).

Jesus is an interesting case because he is a combination of both of the two examples listed above, and was something of an Olympic-level faster (Luke 4:1-13). Uninjured, Jesus definitely would have survived three days without food or water lying down in a cool tomb.

But Jesus was injured--he was close enough to death that Roman soldiers thought he was dead, and after that they stabbed him.

Let's break down Jesus' hydration status throughout the entire ordeal. (Green for hydration events, red for dehydration events)

The last supper: Jesus was at a healthy hydration level after eating a meal.
Psychogenic hematidrosis (sweating blood): this would have dehydrated him some, but we don't know how much.
Two beatings: these would have involved intense physical exertion and possibly blood loss (but we don't know how much).
Crown of thorns: may have caused bleeding, but it wouldn't have been much.
Carrying the cross: Jesus collapsed en route to the crucifixion site, which indicates that Jesus was probably close to exhaustion at this point--or that he had sustained an injury that made carrying a beam of wood particularly difficult (for example, if he had sprained an ankle). It's also possible that Jesus wasn't physically exhausted, but mentally exhausted at this point (remember, he was distressed enough to sweat blood). At any rate, we don't know how exhausted he was, but he definitely would have been getting dehydrated.
Nails: blood loss from these wounds would not have been substantial, because the nails stayed in the wounds. This would have prevented much blood loss (medical side note--if you ever get, say, stabbed, leave the weapon where it is until you are in the care of a medical professional).
Hanging from the cross: this would have been physically exhausting. I won't go into detail here on why hanging from a cross is exhausting, but we could equate it to running 1 or 2 marathons in a row without a break (depending on how long he was on the cross). This would have severely dehydrated him. Not only was he constantly exerting himself to breath, he was completely exposed to the sun. He would have been sweating like crazy.
Hydration: Jesus received hydration while hanging on the cross (we have one documented instance of this happening). This could have been seen as a merciful gesture, easing his thirst, but it could be seen as equally cruel, as hydration would have prolonged the suffering. Jesus refused to drink wine mixed with myrrh just before his crucifixion (Mark 15:23). However, he accepted sour wine just before passing out:

"28After this, Jesus, knowing that all things had already been accomplished, to fulfill the Scripture, *said, “I am thirsty.” 29 A jar full of sour wine was standing there; so they put a sponge full of the sour wine upon a branch of hyssop and brought it up to His mouth. 30 Therefore when Jesus had received the sour wine, He said, “It is finished!” And He bowed His head and gave up His spirit." (John 19:28-30)

I speculate that over the course of the crucifixion Jesus received multiple drinks of sour wine, but we don't know. The jar of sour wine was present, the sponge was present, the branch of hyssop was present, and it's purpose was specifically to hydrate the victims.

We only know what is included in the text, which is unfortunate. Jesus could have actually been very hydrated if he received many drinks. Keep in mind--just because Jesus refused the drink before his crucifixion doesn't mean that he kept refusing drinks. According to William Lane:

"According to an old tradition, respected women of Jerusalem provided a narcotic drink to those condemned to death in order to decrease their sensitivity to the excruciating pain . . . . When Jesus arrived at Golgotha he was offered . . . wine mixed with myrrh, but he refused it, choosing to endure with full consciousness the sufferings appointed for him (The Gospel of Mark, p. 564)"

So Jesus didn't want to drink the wine mixed with myrrh, but he was happy to drink the sour wine.
We have one documented instance of him stating his thirst and receiving a drink. Based on that I think it is likely that he received drinks whenever he asked for them, which would have actually kept him fairly well hydrated.
Passing out: The fact that Jesus passed out just after receiving a drink means that, most probably, he was very dehydrated. He may have been in hypovolemic shock. We don't know how long he was on the cross after passing out, which would have been an immensely helpful metric for us. If he passed out, and 10 minutes later he was taken down, the drink he had just before passing out wouldn't have been absorbed yet (so it's more likely that he would recover after some time). If he passed out and remained on the cross for several more hours, he was probably flat out dead and we don't even need to have this conversation.
Spear wound: The spear wound could have caused so much blood loss that he died instantly, or avoided all major blood vessels and caused minimal bleeding. It at least bled some (of course it did, it was a spear wound) as documented in the New Testament. This would have caused further dehydration on top of whatever dehydration state Jesus was already in. I discuss the spear wound in depth in this post:

If Jesus was alive after being taken down from the cross and being stabbed, we don't know whether or not he could have survived dehydration in the tomb, because we don't know his baseline level of hydration when he was taken down from the cross.

At best, Jesus received a substantial amount of sour wine, drank just before passing out, was taken down (and stabbed) soon after passing out, and recovered consciousness at some point while lying down in the cool tomb.

At worst, Jesus died of hypovolemic shock before they took him down from the cross.

And that's the problem with this entire endeavor, the more I search down this path. There is simply too much that we don't know. We don't know how bad Jesus' injuries were. We don't know exactly how long he was on the cross. We don't know how hot it was that day. We don't know how many pushups the soldiers could do. We don't know the exact nature and severity of the beatings. We don't know exactly where Jesus was stabbed. There is just so much essential information that we don't have.

But is it possible that Jesus survived (and specific to this post, didn't die of dehydration)? Yes.