Thursday, January 22, 2015

Even Snow Creatures Want to Read

A bit of Winter Term whimsy... this snow creature appeared recently at the science library northeast corner, perfectly poised for over the shoulder reading.  Carmen Azevado seems unfazed by the scrutiny.

Thursday, January 15, 2015

Student and Faculty publications in Neuroscience and Geology

New publications from Oberlin students and faculty, as indexed in Web of Science:

Leslie, William R. (OC’15), Kristopher B. Karnauskas, and Jan H. Witting. 2014. The equatorial undercurrent and TAO sampling bias from a decade at SEA (vol 31, pg 2015, 2014). Journal of Atmospheric and Oceanic Technology 31 (12) (DEC): 2871-. [Oberlin users, access this through JournalFinder]

Goldfarb, Stephanie; Naomi E. Leonard; Patrick Simen, Assistant Professor Neuroscience; Carlos H. Caicedo-Nunez; and Philip Holmes. 2014. A comparative study of dift diffusion and linear ballistic accumulator models in a reward maximization perceptual choice task. Frontiers in Neuroscience 8 (AUG 5): 148.

Karsilar, Hakan; Patrick Simen, Assistant Professor Neuroscience; Samantha Papadakis (OC’15); and Fuat Balci. 2014. Speed accuracy trade-off under response deadlines. Frontiers in Neuroscience 8 (AUG 15): 248.

"Frontiers is a community-oriented open-access academic publisher and research network."  About Frontiers.

Friday, January 09, 2015

Open Access article: Elrod, et al., on organic aerosol components.

A new publication from the Elrod laboratory, as indexed in Web of Science: 

atmospheric-chemistry-and-physics.net/ 

Birdsall, Adam W. ’14; Miner, Corina R. ’15; Mael, Liora E. ’16; Elrod, Matthew J., Professor of Chemistry.
Mechanistic study of secondary organic aerosol components formed from nucleophilic addition reactions of methacrylic acid epoxide.

ATMOSPHERIC CHEMISTRY AND PHYSICS, 14 (23):12951-12964;  2014.   www.atmos-chem-phys.net/14/12951/2014/  Open access

Saturday, December 13, 2014

Misuse of "study drugs" can be harmful

In the media, there are many reports of college students misusing prescription drugs to enhance their ability to study; see, for example, WebMD, CNN and the New York Times.

As we move into finals week, some readers may be planning on using study drugs to help their grades. For these readers I want you to understand how these drugs affect your body and why you may want to refrain from using them if you have other medical conditions. Whether you plan on using study drugs or not, I hope that you find this information interesting and that you will be able to use some of the Science Library’s resources to learn more about them. 

Structure of Amphetamine (Adderall)
Source: Wikimedia Commons
What are study drugs?
Study drugs are substances taken to increase mental functions such as attention, concentration, alertness, memory, motivation, planning, and decision-making. The most widely used are stimulants such as methylphenidate (Ritalin, Concerta), amphetamine (Adderall), and modafinil (Provigil). These medications are widely prescribed because they are useful for controlling symptoms of attention deficit hyperactivity disorder (ADHD) (methylphenidate, amphetamine) or excessive daytime sleepiness associated with narcolepsy and other sleep disorders (modafinil, amphetamine, methylphenidate). (1)

In the last two decades, there has been a dramatic increase in stimulant prescriptions, probably due to increased awareness and diagnosis of these disorders. This has led to greater availability of these drugs for people that were not prescribed them. (2)

How do they act?
They act similarly to a family of key brain neurotransmitters called monoamines, which include norepinephrine and dopamine, by enhancing their effects. The increase in their effects can induce a feeling of euphoria when stimulants are taken nonmedically. This can lead to addiction and abuse of these drugs. (2)

Stimulants also increase the action of the sympathetic nervous system; increasing blood pressure and heart rate, constricting blood vessels, increasing blood glucose, and opening up breathing passages. (2)

Problems with study drugs:
Stimulants increase alertness, attention, and energy, as well as elevate blood pressure, heart rate, and respiration. However, withdrawal can result in symptoms that are opposite to the positive effects, including fatigue, depression, and disturbed sleep. Abuse of stimulants can lead to feelings of hostility, paranoia, and psychosis. High doses can result in dangerously high body temperature and irregular heartbeat as well. Additionally, there is the potential for cardiovascular failure or seizures with abuse of stimulants. (1)

Study drugs can interact with other medications you are taking or with pre-existing medical conditions. Do not mix stimulants and over the counter cold medicines that contain decongestants, because combining these substances can cause dangerously high blood pressure or irregular heart rhythms. (2)  If you are getting sick during finals week and taking medicine, you should avoid taking stimulants.

Do not use stimulants like Adderall if you have glaucoma, severe anxiety, heart problems, or a family history of muscles twitches or Tourette’s syndrome. You should also avoid using them if you have taken a monoamine oxidase (MAO) inhibitor in the past two weeks because a dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, phenelzine, rasagiline, selegiline, and tranylcypromine (3).

Additionally, there is limited and inconsistent evidence to support the pro-cognitive effects of these drugs in healthy, non-sleep-deprived individuals, though they are often perceived that way by those who are taking them (4).

If you want to know more:

Search SciFinderPubMed, or Web of Science; try keywords such as nootropics, amphetamines, academic doping or cognitive enhancing drugs.  You may want to start by filtering for reviews. If you want a more general overview, try a subject search in OBIS on substance abuse.  Here are two useful reference sources:

Substance abuse: a reference handbook / David E. Newton
Santa Barbara, Calif. : ABC-CLIO, c2010

Psychopharmacology : drugs, the brain, and behavior, 2nd ed  / Jerrold S. Meyer, Linda F. Quenzer
Sunderland, Mass. : Sinauer Associates, c2013

If you want assistance, come to the science library reference desk and we can help you search.
Sources:
  1. Steiner H., Van Waes V. Addiction-related gene regulation: risks of exposure to cognitive enhancers vs. other psychostimulants. Prog Neurobiol. 2013 Jan;100:60-80. doi: 10.1016/j.pneurobio.2012.10.001. Epub 2012 Oct 17.
  2. http://www.drugabuse.gov/publications/research-reports/prescription-drugs/stimulants
  3. http://www.drugs.com/adderall.html
  4. Hildt E, Lieb K, Franke AG. Life context of pharmacological academic performance enhancement among university students – a qualitative approach.BMC Medical Ethics 2014;15:23. doi:10.1186/1472-6939-15-23.
Contributed by James Medina, Science Library Student Reference Assistant

Friday, December 05, 2014

All About Caffeine

Finals are coming up soon! How much do you know about how all that coffee you’re drinking is affecting your body? 

What is caffeine?
Caffeine is a bitter white crystalline alkaloid that acts as stimulant and a mild diuretic. It is found in the beans, leaves, and fruits of more than 60 plants. In these tissues it serves as a pesticide, killing or paralyzing insects that feed on them.(2)
commons.wikimedia.org

Where does it come from?
Major sources of caffeine for human consumption come from coffee, tea, and cocoa. Guarana, kola nuts, and yerba mate are also cultivated for use as sources of caffeine in energy drinks and snacks.(2)

Who consumes caffeine and how much do they have?
Caffeine is the most widely consumed stimulant in the world. Adults in the US consume an average of about 300 mg of caffeine a day, and 80% of adults in the US consume caffeine in the form of coffee or tea on a daily basis.(2) 97% of the total caffeine consumed comes from beverages, and coffee accounts for the majority of these beverages.(4) An average adult in the US consumes about 3.3 9oz cups of coffee per day.(1) 

What does it do?
Average doses (85-250 mg, the equivalent of 1-3 cups of coffee) can result in feelings of alertness, decreased fatigue, and eased flow of thought.  High doses (250-500 mg) can result in restlessness, nervousness, insomnia, and tremors.(3) 
At very high doses, caffeine can cause seizures and cardiovascular instability.  Overdosing on caffeine is difficult because a fatal dose in adults, 10g, is over 20x what most people consume in a day.(3)  With that in mind, the FDA still recommends that the average daily intake of caffeine for adults should be less than 500 mg per day.(2)

How quickly does it act, and for how long?
After being ingested, caffeine is rapidly absorbed. It is detectable in the blood after only 5 minutes and reaches its peak levels after 30-60 minutes.  The half life varies from person to person, but generally is about 5-8 hours, meaning that in 5-8 hours only half the caffeine you ingested will remain in your system. If you are a tobacco smoker however, it is cleared from your body more quickly.(3)

How does it work?
The nucleoside adenosine plays many roles in your body, one of which is to promote sleep and suppress wakefulness.(3) Caffeine acts as an adenosine antagonist, binding to adenosine receptors and preventing adenosine from binding to the receptor.(5) This results in the opposite action of adenosine, causing your blood vessels to dilate and your central nervous system to be stimulated.(3)

Caffeine also induces the release of signaling molecules such as norepinephrine and epinephrine, increasing heart rate and blood vessel dilation, as well as increasing oxygen absorbance at the lungs.  It can also induce a number of metabolic changes, increasing blood sugar and blood filtration at the kidney. It also increases the amount of acid in your stomach and increases the movement of food through your digestive tract.(3)

How can this help you as a student?
Doses of caffeine over 100mg reliably produce beneficial effects for reaction time, sustained attention tasks, alertness, mood, and wakefulness.  Additionally, glucose has synergistic effects with caffeine, benefiting sustained attention and verbal memory.(6)

Chronic low doses of caffeine have been shown to prevent learning and memory impairment in animal models of Alzheimer’s disease.(5) However, this has not yet been reported in humans. 

If you want to know more:
Search SciFinder, PubMed, or Web of Science for information about caffeine; you may want to start by filtering for reviews. If you want a more general overview, try a subject search in OBIS on caffeine.  If you want assistance, come to the science library reference desk and we can help you search.  Here are a few recommended titles:


Sources:
  1. National Coffee Drinking Trends 2010, National Coffee Association
  2. Food and Drug Administration 2010 Caffeine Report
  3. http://emedicine.medscape.com/article/821863-overview#a0101
  4. Laszlo SP. Caffeine Intake By the U.S. Population. US Food and Drug Administration.
  5. J Alzheimers Dis. 2010;20 Suppl 1:S3-15. doi: 10.3233/JAD-2010-1379. Caffeine and adenosine. Ribeiro JA(1), Sebastião AM.
  6. Hum Psychopharmacol. 2010 Jun-Jul;25(4):310-7. doi: 10.1002/hup.1115. Effects of caffeine and glucose, alone and combined, on cognitive performance. Adan A(1), Serra-Grabulosa JM.


Contributed by: James Medina, Science Library Student Reference Assistant

Monday, December 01, 2014

What do you know about Ebola?

The most recent Ebola outbreak has gained international attention and aroused much fear due to the severity and ease of contraction of the virus.  The infection and mortality rates in Liberia, Guinea, and Sierra Leone are startlingly high and have caused immense stress not only on the health care system but also on the social and economic health of the countries. 


Ebola virus graphic, courtesy of the Center for Disease Control
The virus can be contracted through contact with blood, secretions, organs, and other bodily fluids of someone who has been infected, alive or deceased, as well as materials these fluids have contacted.  In the principally affected countries, women are at higher risk of contraction due to the cultural and societal expectations of caring for the sick and dead.  Despite having contact with infected people, people may not realize they are infected until treatment is ineffective due to the late onset of symptoms and denial.  

The primary indications of contraction are similar to other diseases: fever, headache, and muscle pain; in later stages vomiting, stomach pain, and unexpected bleeding and bruising are common.  The basic screening method is fever detection, but the accuracy is not reliable because the onset of symptoms after infection is anywhere between 2 and 21 days.  Because of the delayed onset and the tendency for people to lie about their activities and whereabouts during a trip to a country with high prevalence of the virus, airport screenings have been minimally effective in preventing the spread of Ebola to other countries. 

Prevention is as simple as avoiding contact with infected people and spaces, but this can prove to be incredibly difficult when the prevalence is high and people do not know they are infected.  This also causes stigma against people who were infected and have recovered; family, friends, and neighbors do not want to come into contact with them. 

Fear of contraction has also led to economic disruption: people are not leaving their homes to work or purchase goods, which has severely affected the national economies in Guinea, Liberia, and Sierra Leone.  In addition, closed borders and abandoned farms are driving up food costs, limiting access to food for people in rural areas in particular and leading to potential starvation.  Exports have also been largely halted, adding stress to the depletion of the economy by the priority for emergency funding.  

The educational systems have also been severely affected; schools have been closed, compounding an already stressed system especially for girls who only more recently started attending school.  Further delay of progress may lead to even higher dropout rates and may cause literacy rates to decline. 

Despite the widespread and disastrous effects of Ebola, a vaccine is still in the developing phases.  It has taken a “crisis”, and one that affects many more countries, to push scientists and their financial supporters to explore drugs and vaccines for the virus. 

International aid has been steady since the outbreak became serious, but it raises many concerns.  By sending money and doctors, foreigners are upholding the power dynamic already present in the post-colonial (neocolonial) countries.  While aid is necessary to support the limited resources of the affected countries health care systems, Western medicine is upheld as superior and essential for progress.

The Ebola outbreak has caused international discussion and action, and will hopefully be resolved in a way that will benefit the people and countries most severely affected.
Contributed by:  Carmen Azevedo, Science Library Student Reference Assistant

Black holes, Nanoparticles, Cocrystal formation, and Phylogenetic signals: new publications from Oberlin authors

Names of Oberlin faculty and students are indicated in bold text:

Arzoumanian, Z., A. Brazier, S. Burke-Spolaor, S. J. Chamberlin, S. Chatterjee, J. M. Cordes, P. B. Demorest, et al., including Daniel R. Stinebring, Professor of Physics. 2014. Gravitational waves from individual supermassive black hole binaries in circular orbits: Limits from the North American Nanohertz Observatory for gravitational waves. Astrophysical Journal 794 (2) (OCT 20): 141.  [access at iopscience.com]
Astrophysical Journal 794 (2), fig. 6

Krycka, K. L., J. A. Borchers, R. A. Booth, Yumi Ijiri, Professor of Physics, K. Hasz, J. J. Rhyne, and S. A. Majetich. 2014. Origin of surface canting within Fe3O4 nanoparticles. Physical Review Letters 113 (14) (OCT 2): 147203. [access at aps.org]

Mandala, Venkata S., OC '15, Sarel J. Loewus, OC '16, and Manish A. Mehta, Professor of Chemistry. 2014. Monitoring cocrystal formation via in situ solid-state NMR. Journal of Physical Chemistry Letters 5 (19) (OCT 2): 3340-4. [access at pubs.acs.com]

Straub, Shannon C. K., Michael J. Moore, Associate Professor of Biology, Pamela S. Soltis, Douglas E. Soltis, Aaron Liston, and Tatyana Livshultz. 2014. Phylogenetic signal detection from an ancient rapid radiation: Effects of noise reduction, long-branch attraction, and model selection in crown clade apocynaceae. Molecular Phylogenetics and Evolution 80 (NOV): 169-85. [access at sciencedirect.com]

Wednesday, November 12, 2014

Neuroprosthetics featured in The Scientist

From The Scientist: Neuroprosthetics a fascinating look at advances in devices that "supplant or supplement the input and/or output of the nervous system."

By Eric C. Leuthardt, Jarod L. Roland and Wilson Z. Ray
"For decades, researchers have eyed neuroprosthetics as ways to bypass neural deficits caused by disease, or even to augment existing function for improved performance. Today, several different types of surgical brain implants are being tested for their ability to restore some level of function in patients with severe sensory or motor disabilities."
Two books accessible in the Springer electronic book collection provide context and background:

Operative neuromodulation  / edited by D.E. Sakas, B.A. Simpson, and E.S. Krames. Springer, c2007.

Springer handbook of medical technology  / edited by Rüdiger Kramme, Klaus-Peter Hoffmann, Robert S. Pozos.  Springer, c2011

Browse the contents of this journal in the OhioLINK EJC for a more extensive reading of these exciting developments:
Neuromodulation: Technology at the Neural Interface