Monday, August 26, 2013

On working in Food Service

As I've mentioned here before, I spent the last year and change working as a server at a small restaurant in my college town. I originally took this job thinking I would wind up having more time to blog, but that turned out not to be the case. In a given week I'd spend between 40-50 hours at the restaurant, mostly working double shifts. I'd show up at 10:30 am, have a break for about an hour and a half in the middle of the day, and then leave work anywhere between 9 and 10 pm. Between work and applying to graduate school, I had very little time and energy leftover to devote to my blog. However it all paid off because I'm starting graduate school and actually saved up some money to be able to go.

If I could do it again, I think I'd do everything the same way. Maybe I'd put my foot down a little harder about the number of hours I worked, but to be honest, I loved working in the restaurant. It had its ups and downs like any job, but at least it was never boring and I wasn't just sitting in front of a computer screen all day. I had fun, I met some great people, and learned so much about work and life. I also learned how little people understand the service industry. It may not have anything to do with science, but I wanted to write two lists. The first about what food service taught me, the second about what patrons should know about food service.

What Food Service taught me:

  1. Patience. Someone is angry with the way their food turned out and wants to spend 10 minutes (i.e. forever in restaurant time) telling you everything that's wrong with it. A customer thinks he's ready to order but spends another five minutes hemming and hawing over the menu while you're trapped there. Just breathe, keep your cool, and wait and listen. The world will keep spinning.
  2. Multi-tasking. There's an ass in every chair and everyone needs something. Run table 1's food, on your way back grab table 5's check and ask how table 6 is doing. Run table 5's check and then stop by table 8 on the way back to take their order. Boom. Efficiency.
  3. Kill 'em with kindness. From the moment table 6 walked in you could see they were trouble. Maybe they were fighting in the car on the way to the restaurant. Maybe they've had a bad day and want to take it out on someone. Either way, if you walk up to them with a big friendly smile and a helpful disposition, you're going to save yourself a lot of grief, and if you're lucky they'll leave happier than when they came in.
  4. The squeaky wheel gets the grease. Customers who are vocal with their needs, comments, and complaints will get more focused service. HOWEVER. Customers who are vocal with their needs comments and complaints and are POLITE, PATIENT, AND KIND to their server get the best service. More on that later.
  5. Attitude is everything. The best attitude is positive, self-confident, but always willing to learn. The worst attitude is to think you don't need to learn anything new.
  6. Taking criticism is an important life skill. When taking criticism about yourself it's important to a. lower your defenses, and b. listen. When someone is telling you that you did something wrong, it's easy to hide behind your intentions. However intentions don't affect the world, actions do. So when someone is telling you how to do something better, even if they're yelling it at you in frustration, listen.
  7. Don't take everything personally. When you wait tables in a college town, you get a lot of bad tips, even when your service is great. When you wait tables anywhere, you get a lot of rude customers. People don't always say please, thank you, or even treat you like a human being when you're in the service industry. It doesn't take long for most servers to learn to not sweat the small stuff.
Things customers should consider when eating out:
  1. The minimum wage for servers in most of the US is $2.13 per hour. Servers literally make their living off of your tips, so don't be stingy. Even if your service was terrible you should at least tip 15%. Most servers aren't hired without experience and are therefore at least competent at their jobs, and chances are if they messed up it was just a goof or it wasn't even their fault (something went wrong in the kitchen or elsewhere.) After all, we all goof up at our jobs, but few of our jobs will pay us less when we make a mistake or two.
  2. Servers do not keep every penny of their tips. Most restaurants have a lot of support staff. Bussers, food runners, hosts, bartenders etc. that help the servers during the rush. Most restaurants also have a system where the servers must give away a portion of their tips to the support staff every night. This can mean that the server ends up walking home with only 60-70% of their tips. Moreover, tip-outs are usually calculated based off the server's sales, not their tips. So if you don't tip at all, then the 2% of your bill that goes to support staff that would normally come out of your tip comes out of the server's pocket instead. In other words, if you don't tip then your server essentially has to pay out the support staff themselves, and your server basically just paid for you to eat at their table.
  3. If you are vegan, gluten-free, or allergic to anything, tell your server BEFORE you order anything, and be honest. I can't tell you how many times I had a table order a vegetarian appetizer only to ask me, as they were eating their app, what was vegan on the menu. That puts me in an awkward spot. Do I tell them that the appetizer they're raving about has egg in it? Do I let it slide? I can't read your mind, you have to tell me before you order that you're vegan. When it comes to allergies, it pays to be honest. It's astonishing how many times people will insist they have allergies to something when they just don't like it or are avoiding it for diet reasons (ahem, gluten.) Just be honest. Servers actually want to make you happy. It's our job. If you want to avoid the gluten in the breading on the chicken, fine. But don't tell me you're severely gluten intolerant and then ask me for soy sauce (which is full of gluten.)
  4. If you have any time constraints, tell the host when you arrive. Then tell your server when you sit down. Five minutes before you have to catch your movie is not the time to tell me that you need your to-go boxes and check NOW. However, if you tell me ahead of time, I can be honest with you about what will come out quickest from the kitchen, and I can bring your check out with your food. Similarly, if you are in a rush, do not expect your ticket to be jumped to the front of the line. That is not fair to the other customers and you are not your server's one and only priority, either. If you are in a huge rush then consider fast food.
  5. If, for whatever reason, you have a problem with your food, let me know immediately. This is where the squeaky wheel gets the grease. If you tell me at the end of your meal that you hated your food, well there's not much I can do about it then. But if you just had a couple bites and it's too spicy, not spicy enough, too cold, or you just don't care for it, let me know as soon as you can. But I cannot stress enough how important it is to be polite and patient when alerting your server to any issues with your food. If you simply say "excuse me, but my food is cold, could you please heat it up for me?" Or, "I just don't care for dish, would it be possible for me to order something else?" you are going to get wayyyyyyyyyyyy better service than if you say "this is disgusting" with a big old frown. As servers, we get it, you come in with an expectation and when those expectations are not met, it's frustrating. But it's our job to make you happy, and we want you to be happy so help us to help you. Be polite, be understanding that if you order something else it might take a little bit for it to come out. My mother always said, "you catch more flies with honey than with vinegar."
  6. Whenever you eat out, take a look around the restaurant. Are they really busy? How many employees can you spot walking around? Knowing these questions can really help. On occasion I worked solo shifts at my restaurant. I was the only server, there was no host or busser. It amazed me how little people were aware of that and thus expected the service to be perfect. If you see 10 other tables and only one person working, then you can expect that your service is going to be a little slower. Restaurants are run by humans, after all.

Monday, August 12, 2013

Megalo-debacle: Did Discovery Really Commit a Faux-Pas?

For over two decades, Shark Week on Discovery Channel has been raising awareness of one of the ocean's most mysterious and powerful predators. Discovery originally started Shark Week with the purpose to dispel myths about the dangers of sharks, and to heighten the public's respect for the creatures. However, this year, many fans have felt outraged that Discovery may be straying further away from the original purpose of Shark Week. This year, Discovery unveiled the faux-documentary, Megalodon: The Monster Shark That Lives.

Megalodon, for the record, are definitely, absolutely extinct. They were super-sized sharks that once roamed the oceans some 2 million years ago.

Relative size of Megalodon (red and grey) vs. human. Source.

The Discovery special, on the other hand, suggested an alternative. Megalodon still roams the oceans, somewhere off the coast of South Africa. The documentary looked and seemed like any other documentary about real life events (however fantastic.) It convinced 70% of viewers that Megalodon could still live today. However, it was all fake. If you blinked you may have missed the disclaimers posted in small print:
"None of the institutions or agencies that appear in the film are affiliated with it in any way, nor have approved its contents."
"Though certain events and characters in this film have been dramatized, sightings of [the Megaladon,] 'Submarine' continue to this day."
"Megalodon was a real shark. Legends of giant sharks persist all over the world. There is still debate about what they may be."
These disclaimers appeared and disappeared quickly. Even if you had time to read them, they were still vague and beat around the bush. Nowhere do any of them directly say, "none of what you are viewing is based in fact."

It didn't take long for the blogosphere to ignite in outrage over the "documentary." Actor Wil Wheaton demanded Discovery apologize for misleading their audience. Popular science communicator, Christie Wilcox, wrote an open letter expressing her disappointment and anger with the direction Discovery has chosen to take with this year's Shark Week. Fans and scientists took to twitter to express their frustration. However, Discovery has stood by its documentary. Shark Week executive producer, Michael Sorensen, released this statement:
With a whole week of Shark Week Programming ahead of us, we wanted to explore the possibilities of Megalodon. It's one of the most debated shark discussions of all time, "can Megalodon exist today?" It's the ultimate Shark Week Fantasy. The stories have been out there for years and with 95 percent of the ocean unexplored, who really knows?
This statement is even more misleading. Asking "can Megalodon exist?" is not the same as asking, "does Megalodon exist?" which was the question the documentary was really asking.

When I first heard that the documentary was fake, I posted a link to Christie Wilcox's open letter on my facebook. It got several shares and comments from my friends who were as upset and disappointed as I was. Eventually my sister chimed in with a point that stopped me dead in my self-righteous tracks.
Maybe I'm missing something because I haven't seen [the show] but I'm not sure why it's generating this level of outrage. Annoyance, sure. Disappointment, totally fine. But that article is way over the top. They made a fake documentary and weren't so forthcoming with the "fake" bit (intentionally, I'm sure). They had 70% of viewers going for a minute there. Seems like that was probably the point right? They probably counted on the outrage from the science community to make their disclaimer for them. Success on all counts! Plus anyone who wasn't already aware now knows Shark Week has kicked off. I think expectations that Discovery is anything but a TV channel with a marketing plan are kind of off.
I think my sister, Laura, makes a lot of good points here and raises many important questions. First off: what responsibility does a TV channel have to present facts? They made the disclaimers, however vague and however quickly. And, as Laura pointed out, if there was anyone who missed the disclaimers, they certainly know now that the documentary was fake. Do we really have the right to be outraged? Are we, the "science community," just personally offended that Shark Week no longer meets our standards for good educational television? Or does Discovery have an obligation to uphold the original purpose and message of Shark Week from 26 years ago? I want to hear your thoughts. Discuss!

Monday, June 3, 2013

Getting Sprung: The Biological Underpinnings of Spring Fever

This article is being published here with permission from The Synapse. It originally appeared in the Spring 2013 edition of The Synapse at Oberlin College.

Before I was a student at Oberlin, the phrase “Spring Fever” meant little to me. However, once I matriculated the seasons grew more palpable. Perhaps it was the daily hikes around campus, but something about the air seemed to penetrate deeper into my skin. I felt especially vulnerable to the mood swings of Ohioan weather. I dealt with winter by resigning to it.

On the auspicious day when the clouds surrendered to sunshine and warmth, I was thrust out of my hibernation by the delicate savor of flowers and fresh grass. The sun filled me with a restless energy that invited me to skip class, sit out on North Quad, and look for four-leaf clovers with a friend. I partied later into the night and struggled to fall asleep as the birds chirped in the early morning. Over time, it became clear to me that many students are stricken with this same “fever” come spring. A particularly bright-eyed friend became especially reanimated in spring, proclaiming he was “solar powered.”

Talk to any Obie long enough and eventually you will learn the unique way that the seasonal changes in sunshine and warmth affect them. Their explanations range from the transformation of the monotonous winter grey into bright blue skies, longer days, warmer air, and a pleasant scent of renewal. But is there a more deep-seated biological rationale for such changes in mood and behavior? Is Spring Fever merely a social construct or is it an artifact of evolution?

“I would not be surprised if there was a biological imperative to go out and have fun in the spring,” muses Zachary Weil, an assistant professor at the Wexner Medical Center of Ohio State University. Weil, who studies seasonal changes in behavior and physiology in animals, speculates that the drive to get vitamin D from sunlight has something to do with Spring Fever. When the ultraviolet wavelengths in sunlight strike the skin, they stimulate light-reactive chemicals to synthesize vitamin D. The increased production of vitamin D in sunnier months may improve both physical and emotional health.

Overall, the scientific literature on Spring Fever is sparse. Just as it is impossible to appreciate light without darkness, scientists find it useful to study what drags us down in the winter, and to assume that the alleviation of those factors causes us to bounce back in the spring.

Melatonin, affectionately known as the hormone of darkness, is associated with seasonal changes in mood, behavior, and health. The pineal gland in the brain modulates the production of melatonin based on light levels. When light enters the eye, it stimulates neurons that connect to hypothalamus which tells the pineal gland to stop producing melatonin. However, if the pineal gland remained in darkness, it would modulate melatonin cyclically, approximately 10-hours-on, 14-hours-off. According to Weil, the pineal gland can sometimes “think” it is in darkness during the day.

“We're not aware of this consciously—because our eyes adjust so quickly—but the lights inside our offices and homes are orders of magnitude dimmer than the lights outside.” Sunlight, says Weil, is around 10,000 times brighter than incandescent and fluorescent bulbs. “People in northern climates that might go to work before the sun comes up and leave work after the sun goes down may never be exposed to the level of sunlight that's necessary to turn down our melatonin production.” Fathom the brain as an ancient machine responding to archaic devices such as the eyes and ears and it is conceivable that the brain may interpret this situation as perpetual darkness.

Conversely, once the days begin to lengthen and people are exposed to more morning sunlight, the brain produces melatonin for shorter intervals. The difference in melatonin production in the winter versus the spring is the predominant rationale for the prevalence of winter depression, or Seasonal Affective Disorder (SAD) in northern latitudes. Melatonin's effect on mood and behavior is complicated, though. Even though longer periods of melatonin production have been associated with SAD, melatonin can also be used as a treatment for people suffering from winter depression. Experimental therapies have shown that depending on when the dose is given, in conjunction with the patient's natural sleep-wake cycle, melatonin can actually help regulate the circadian rhythm and relieve depression. In general, melatonin production that begins in the evening and stops in the early morning helps most people combat the winter doldrums, which mimics a springtime daylight cycle.

For Obies though, nothing competes with actual sunshine and warm air. Fourth-year Nicole's* fondest spring memory happened in the last few days of her first year. Having just pulled three consecutive all-nighters to finish a paper, she shifted her focus to an attractive classmate. “I remember running into him at Stevie, [the school dining hall] but even inside Stevie it smelled like spring.” Emboldened by the triumph of having just completed her freshman year, she decided to catch up with him later that night at a party. “I remember walking back home with him, and I don't know, there was just something in the air.”

Things fizzled out between Nicole and her spring fling, but her experience remains an idyllic memory of springtime in Oberlin. “I was totally giddy and euphoric. It was a very spring collegiate freshman year experience.” Nicole's experience is one of many similar ones from several students I interviewed about their experiences of springtime in Oberlin. Some ancient vestige of biology springs from the increase in vitamin D, the decrease in melatonin, mixed with end-of-the-year excitement to foster delight among the students.

*Name has been changed to protect the student's privacy.

Monday, April 29, 2013

MDMA, "Drugs Live," and a life update.

It's been a while.

Last summer, I became inspired to write an article about the potential benefits of the club drug, MDMA, otherwise known as Ecstasy or Molly. The blog post got turned into an article for my alma mater's science magazine, The Synapse, and was published a few months ago. With permission, I am cross-posting it here.

A quick life update for anyone who is interested will be at the bottom of this post.

In Europe and the United States, the drug known as ecstasy is the magic bullet that loosens the inhibitions of many dancers at all-night dance parties known as “raves.” Ecstasy—or “Molly” in its allegedly purer form—is a psychedelic drug with a signature high that produces an intense sensory experience coupled with feelings of euphoria and closeness with others. However, ecstasy's tendency to raise body temperatures and dehydrate users in over-packed, sweltering clubs creates a dangerous situation that troubles parents and politicians alike.

Though ecstasy has been the culprit behind some tragic deaths since its popularization in the mid-eighties, death and injury from ecstasy are relatively rare compared to other drugs scheduled I or II by the DEA. The number of emergency room visits per year resulting from the use of ecstasy are tens of thousands fewer than those due to the use of cocaine, heroin, and marijuana. Every year, the number of deaths from ecstasy are miniscule relative to tobacco- and alcohol-related deaths. Some experts believe that MDMA, the primary chemical constituent behind the ecstasy high, isn't the real danger of ecstasy. Instead, they believe that it is the crowded, hot dance floors combined with the effects of the many other substances ecstasy is famously adulterated with that puts users in danger.

Despite the risks, MDMA's signature high has not only beguiled party-goers. The drug has also intrigued many scientists with its potential therapeutic benefits. In hushed sessions behind closed doors, therapists in the seventies and eighties began to explore the drug's ability to release patients from painful emotions attached to traumatic experiences and to strengthen the therapist-patient alliance. Although the anecdotal evidence was in favor of MDMA as a therapeutic drug, no placebo-controlled clinical trials had been performed by 1985, which was when MDMA was on the table for scheduling by the DEA. Due to the lack of clinical data, and MDMA's perceived dangers in the club scene, the drug was labeled as Schedule 1: a harmful drug with no medical benefits. All research on the therapeutic effects of ecstasy were halted for the next two and a half decades.

Nevertheless, MDMA has only become more ubiquitous among young people since 1985, and the cries to research the actual effects of MDMA on the human body have gradually swelled to a dull roar. However, the US and British governments have little to no precedent for funding studies on MDMA in humans. In 2010, Channel 4 in London endowed Professors David Nutt and Val Curran with funding to begin the first fMRI study of MDMA's effects in the human brain. The results of the study were broadcast live in a TV special called Drugs Live: The Ecstasy Trial late last September.

In the trials, conducted in September 2011, 25 volunteers came in for testing twice. Each time a volunteer came in, they received either an 83 milligram dose of MDMA or a placebo. The study was double-blind, so neither the administrators nor the subjects knew which drug they were getting. 30 minutes after they took the pill, the volunteers entered a fMRI scanner, where they were monitored for 90 minutes while answering questions about their subjective experiences. Throughout this process, volunteers were also asked to recall positive and negative memories from their lives. After the volunteers came out of the scanner, they performed a task in which they rated the trustworthiness of various faces, testing their feelings of closeness with others.

Drugs Live features the experiences of five volunteers: an ordained priest, an ex-soldier, a journalist, an actor, and a former member of Parliament. The show itself consists of clips of the five volunteers' trials on ecstasy, interviews with them and members of the audience, a debate between David Nutt and his loudest dissenter, Andrew Parrott, short videos of recreational MDMA users out dancing or just enjoying a night in with friends, and a video of an illegal therapy session with MDMA. The program is punctuated by fleeting explanations of the results of the study, described by Nutt and host Jon Snow with the aid of a giant, plastic brain with flashing lights indicative of the various structures within.

The first major discovery presented in episode 1 is MDMA's effects on the neural circuit between the posterior cingulate cortex and the prefrontal cortex. This circuit is known to become overactive in people suffering from anxiety disorders and depression, and is believed to lead to the excessive rumination characteristic of mood disorders. Normally, the two nuclei fire in sync with one another, but MDMA releases a deluge of serotonin and causes the two nuclei to start firing out of line, hushing the circuit between them and alleviating anxiety, which leads to the characteristic euphoria of the drug.

After a clip showing a therapy session, in which a woman talks through her feelings towards her recently deceased, abusive father, Nutt walks toward the giant brain to explain how MDMA is helping this woman work through her traumatic memories. When a person recalls a traumatic memory, there is an activation of the amygdala and the prefrontal cortical region. According to Nutt, the prefrontal cortical region modulates the emotions associated with a particular memory, and MDMA works to dampen the firing of that region. Without the chatter of the emotional overlay, patients are better equipped to engage with and process those memories, making MDMA a particularly exciting potential therapy for post traumatic stress disorder.

Though the program opened with a claim of being politics-free, “unvarnished science,” many viewers felt that Drugs Live was more of a “pro-drugs” circus than a lucid exposition of the science behind MDMA. Indeed, there was little discussion of the negative aspects of MDMA, including the “Tuesday blues” experienced by one volunteer in the study and the overall negative experience the ex-soldier had during the trials. There was also little air time for the debate between Nutt, Curran, and Parrott, which some viewers with a scientific background were particularly interested in.

Perhaps the positive bias in Drugs Live is unsurprising to those who know David Nutt for famously suggesting that drugs like cannabis, ecstasy, and LSD were less dangerous than alcohol and tobacco while on the Advisory Council on the Misuse of Drugs. His comments were largely responsible for his subsequent firing from the Council.

Regardless of Nutt's personal opinions on illicit substances, the study performed in Drugs Live is still an exciting contribution to a sparse body of research on the effects of MDMA in humans. Many other studies on MDMA are funded by government agencies such as the National Institute on Drug Abuse (NIDA). These studies tend to be performed on animals with the intention of finding the harmful neurological effects of MDMA. Such studies have shown significant depletion of neurons that produce serotonin that lasts for years after a single round of MDMA administration. However, these single doses are given intravenously over the course of three or four days. Critics say such dosages are not representative of how the drug would be administered in therapy (a low dose taken orally once or twice in a patient's lifetime), nor do they reflect how most recreational users take ecstasy (taken orally once or twice a month.)

Studies on humans are often relegated to surveying cognitive faculties in recreational users of ecstasy, using hair and urine drug tests to determine what sorts of drugs subjects have been taking. There are many criticisms of these studies as well, many citing poor control for subjects who have taken ecstasy in combination with other drugs or alcohol. However, these studies still show many deficits in memory, as well as higher levels of anxiety in current and former ecstasy users. Theseresults foster skepticism for the therapeutic benefits of MDMA.

A viewer watching Drugs Live likely wouldn't catch the troublesome findings of such research on MDMA just from watching the few short minutes where Andrew Parrott attempted to explain it. This was one of many issues that commenters brought up about Drugs Live after it aired. Some criticized Channel 4 for not giving enough credit to its viewers for being able to hold their attention on scientific facts for more than a few seconds. It seemed as though the content of Drugs Live wasn't much different from that of ecstasy found on the street: very little though potent science adulterated with an abundance of questionable filler.

Life update: For anyone who is wondering what I've been up to this past year, I'm still writing! I have also been working a lot waiting tables to save up for graduate school. I will be beginning the science communication graduate program at University of California Santa Cruz in the fall. In addition, I have been writing for The Synapse, and I will be posting my newest article once it comes out in print!

Wednesday, June 13, 2012

The Unsung Scientist, Louis-Antoine Ranvier

To many who read this blog, Notes of Ranvier is a title that probably evokes no thoughts of science or history. There is a backstory to the name, however, and a reason why I chose it as the title.

Notes of Ranvier is meant to be a play on words referring to the nodes of Ranvier, anatomical structures in certain types of neurons that have a myelin sheath. Every neuron has a long projection called an axon that transmits electrical signals to other neurons. Around the axons of some neurons is the myelin sheath, a fatty tissue that insulates the axon like plastic around a copper wire. Electricity can't travel though myelin, so there are even gaps between the sheath where the neuron is exposed and electrical currents can be propagated down the axon. These gaps were discovered by French scientist, Louis-Antoine Ranvier (pronounced rahn-vee-yeh), and thus bear his name as Ranvier's nodes or the nodes of Ranvier.

When you learn about Ranvier's nodes in class, not a lot of attention is paid to how they were discovered or why they have Ranvier's name instead of some other scientist. The treatment of the subject is far more along the lines of, "these exist, this is what they do, moving on." But the question still gnaws, who was Ranvier? How did he find these nodes, and how did he figure out what they do?

Ranvier was a histologist in 19th century France. Histology is the study of organic tissues, employing techniques such as staining and preserving tissues and examining them under a microscope to better understand their anatomy and physiology. When you looked at slides of cells dividing in high school biology, you were performing histology.

While histology and microscopy are so common today that even small children learn how to use microscopes in class, the microscope was renounced by many French scientists and doctors in the 19th century. The dismissal of the microscope was largely related to the dismissal of the cell. Even as late as the 1800's, the theory of the cell being the building block for all living things was still pretty far-fetched to many scholars. This idea known as cell theory, was hotly debated for centuries. But in the latter half of the tumult was Ranvier holed away in his laboratory, with his icepick of a microscope, diligently scratching and scraping on the surface of physiology.

From the time Ranvier was born in 1835 to the peak of his career, histology began to make a sea change in the eyes of French scholars. Histologists were developing newer and more advanced techniques for preserving and staining samples. Ranvier saw the merits of histology for studying anatomy and physiology. In particular, he valued the scrupulousness involved in preparing tissues for histological examination which allowed him to reveal the nodes between myelin sheaths and determine their function.

For a long time it was known that myelin sheaths existed and that they were made up of fatty cells. The cells were and still are called Schwann, after the scientist who identified them. Ranvier wanted to better understand how cells insulated by myelin sheaths were able to exchange nutrients (such as oxygen and ions) with the blood since carmine tissue stains demonstrated that such nutrients could not penetrate through Schwann cells. Closer examination with different chemicals and a more exacting technique revealed the nodes pictured below.
Ranvier's Nodes (e). Image from Barbara, J (2007). Originally from Ranvier, 1878.
Ranvier wasn't finished there. He still wanted to know whether the nodes really were the site for nutrient exchange between the neuron and the capillary. Around the neurons in your body is a small sheet of connective tissue that protects them from mechanical damage. Ranvier destroyed this tissue, and then poured water onto the exposed nerves of living animals. This caused the Schwann cells to swell and expand to cover the nodes. The result? A loss of neuron function and paralysis. Ranvier correctly deduced that the nodes were important for the conduction of signals through neurons.

Ranvier went on to develop some of the first legitimate theories on nerve cell degeneration with his experiments on myelin. Meanwhile, furious debate raged on about the nature of cells and their contributions to the function of the human body. Ranvier, all the while, was only interested in facts and improving his histological techniques. His mentality led to many great discoveries in his life, some of which contributed to our modern understanding of neurophysiology.

He was a man truly deserving of respect and admiration, and his approach to his work should be an inspiration to scientists and science writers alike.

Bracegirdle, B. The History of Histology: A Review of Sources. (1977) Hist. Sci., 15:77-101

Barbara, J. Louis Ranvier (1835-1922): The Contribution of Microscopy to Physiology and the Renewal of French General Anatomy. (2007). Journal of the History of Neurosciences, 16:413-431.

Tuesday, May 15, 2012

Ranvier Returns

Hey everyone! I just wanted to write this to explain my absence.

In the last few weeks I left my job at the lab and decided to move back home to Ohio. I did this because I wanted more time to focus on what I really want to do, which is to write about science. The first step in that process, after the move, was to attend the science writer's workshop in Santa Fe, NM. I learned a lot there and came home feeling renewed and inspired. If you are reading this and are interested in getting into science writing yourself, I highly recommend you click that link above and apply to go to the workshop next year.

Over the next year I would like to write a lot more, but hopefully write for publications as well as here on this blog. So I'll be coming back with actual stories and new posts soon! I'm hoping to revise some of my older posts to make them better, too. If you want to stay up to date with me, follow me on twitter @NotesOfRanvier. I'll also be making a page on Facebook soon, too. So be on the look out!

Here are some photos from Santa Fe:

At the School for Advanced Research 
Prickly Pear Margaritas -- Yum!
I'm not really sure who this lady is or what she was doing but she looked cool so I took a picture.

More Notes of Ranvier soon.

Tuesday, March 13, 2012

Salty Penguins Filter Salt Out Their Nose

The Venture Brothers season 1, episode 5, via [adult swim]

Why yes, penguins do have an organ that converts sea water into fresh water! Except it's not an organ, it's a gland. And it doesn't directly convert sea water to fresh water, it filters salt from the blood.

Hm, maybe I should start from the beginning.

First of all, this organ/gland/whatever that Dean is talking about is called the supraorbital gland, and it's something all marine birds have. Basically any mammal or bird that is going to have to drink sea water to quench thirst is going to need this gland.

Normally, salt that we ingest is absorbed into the blood stream, filtered out by the kidneys, and secreted in urine. However, the penguin's small kidneys can only filter out enough salt to create urine that's about 1/3 the concentration of sea water. If the blood is still too salty, then water must be taken from other tissues to dilute it, and this quickly leads to dehydration.

Penguins have a very high salt load because they drink sea water to quench thirst and eat a lot of salty foods like crustaceans. Located above the nose, in between the eyes, the supraorbital gland lends a helping hand. Both the kidney and supraorbital gland filter salt from the blood in a process called counter-current exchange.

The blood flowing along the gland and the fluid within the gland flow counter, or in opposite directions to one another. One of the principles of osmosis is that molecules will move from fluids with high concentrations of solutes (in this case, salt) to fluids with lower concentrations. I.e. they move down their concentration gradient. So salt leaves blood and goes to the relatively less salty fluid in the duct. Since the blood and the duct fluid are moving in opposite directions, the blood will always remain saltier than the duct fluid, therefore a concentration gradient will be maintained, and the salt will always flow out the blood to the fluid in the duct.

Still confused? There's a pretty great diagram here. For the more verbally inclined, here's a metaphor: Imagine the blood stream and the fluid stream are two trains moving parallel to each other in opposite directions (I promise this won't involve any math). Every car in the "blood" train is full of (rather salty) people, and every car in the fluid train is empty. As the trains meet, the first two cars of each train will be facing each other, and the people from the blood train (with great nimbleness) will jump from the blood train to the fluid train, until the first car in the fluid train is full. Then as the the trains continue to pass, people will continue to jump from the blood train and fill all the cars in the fluid train. People will not jump back onto the blood train from the fluid train because remember, they're going in opposite directions. So as the people that jumped on the first car of the fluid train keep going, they're passing the full cars of the blood train going in the other direction.

What would happen if the blood and the fluid were running in the same direction? That would be called concurrent exchange. The salt would still move from the blood, but quickly the concentrations of salt within the blood and the fluid would become the same and there wouldn't be any net gain or loss of salt in either the blood or the fluid. Pretend those trains are now running in the same direction, and people jump onto the fluid train, but then they see open space in the blood train and jump back. Since there will always be space in both the fluid and the blood trains, and they keep running along next to each other, passengers will keep jumping back and forth.

This diagram illustrates the difference between concurrent (top) and counter-current (bottom) exchange. Blue, in this case, would indicate low salinity, and red would indicate high salinity. As for the percentages, there is never "near 100%" absorption of salt from the bloodstream, as that would be as deadly as having too much salt. So take the percentages with a grain of salt.
From Wikimedia commons

The result is a fluid that is actually saltier than sea water. It flows from the gland and is excreted through the nasal passages. Penguins will often look like they have runny noses, but it's really this salty substance coming out their noses. You could, supposedly, say that they pee out their nose, but that would take away some of the mystique from the magestic emperor penguin, wouldn't it?

Immature jokes aside, this gland allows penguins to consume massive amounts of salt, and still be healthy. Considering how high sodium intake contributes to heart disease, maybe penguins could unlock the biotechnology of the future to allow us to have our salt cake and eat it, too!

John Sparks & Tony Soper. (1987). Penguins. Facts on File, Inc. 460 Park Avenue South, New York, NY.