Author Archives: Katerina-Despoina Zacharis
Sign the Petition for European Researchers
by EuroScience
Scientists from different European countries describe in this letter that, despite marked heterogeneity in the situation of scientific research in their respective countries, there are strong similarities in the destructive policies being followed. This critical analysis, highlighted in Nature and simultaneously published in a number of newspapers across Europe, is a wake-up call to policy makers to correct their course, and to researchers and citizens to defend the essential role of science in society. This letter can be signed here.
2014 Nobel Prize in Physiology or Medicine
at Nobelprize.org
The Nobel Assembly at Karolinska Institutet has today decided to award
The 2014 Nobel Prize in Physiology or Medicine
with one half to
John O´Keefe
and the other half jointly to
May-Britt Moser and Edvard I. Moser
for their discoveries of cells that constitute a positioning
system in the brain
How do we know where we are? How can we find the way from one place to another? And how can we store this information in such a way that we can immediately find the way the next time we trace the same path? This year´s Nobel Laureates have discovered a positioning system, an “inner GPS” in the brain that makes it possible to orient ourselves in space, demonstrating a cellular basis for higher cognitive function.
In 1971, John O´Keefe discovered the first component of this positioning system. He found that a type of nerve cell in an area of the brain called the hippocampus that was always activated when a rat was at a certain place in a room. Other nerve cells were activated when the rat was at other places. O´Keefe concluded that these “place cells” formed a map of the room.
More than three decades later, in 2005, May-Britt and Edvard Moser discovered another key component of the brain’s positioning system. They identified another type of nerve cell, which they called “grid cells”, that generate a coordinate system and allow for precise positioning and pathfinding. Their subsequent research showed how place and grid cells make it possible to determine position and to navigate.
The discoveries of John O´Keefe, May-Britt Moser and Edvard Moser have solved a problem that has occupied philosophers and scientists for centuries – how does the brain create a map of the space surrounding us and how can we navigate our way through a complex environment?
How do we experience our environment?
The sense of place and the ability to navigate are fundamental to our existence. The sense of place gives a perception of position in the environment. During navigation, it is interlinked with a sense of distance that is based on motion and knowledge of previous positions.
Questions about place and navigation have engaged philosophers and scientists for a long time. More than 200 years ago, the German philosopher Immanuel Kant argued that some mental abilities exist as a priori knowledge, independent of experience. He considered the concept of space as an inbuilt principle of the mind, one through which the world is and must be perceived. With the advent of behavioural psychology in the mid-20th century, these questions could be addressed experimentally. When Edward Tolman examined rats moving through labyrinths, he found that they could learn how to navigate, and proposed that a “cognitive map” formed in the brain allowed them to find their way. But questions still lingered – how would such a map be represented in the brain?
John O´Keefe and the place in space
John O´Keefe was fascinated by the problem of how the brain controls behaviour and decided, in the late 1960s, to attack this question with neurophysiological methods. When recording signals from individual nerve cells in a part of the brain called the hippocampus, in rats moving freely in a room, O’Keefe discovered that certain nerve cells were activated when the animal assumed a particular place in the environment (Figure 1). He could demonstrate that these “place cells” were not merely registering visual input, but were building up an inner map of the environment. O’Keefe concluded that the hippocampus generates numerous maps, represented by the collective activity of place cells that are activated in different environments. Therefore, the memory of an environment can be stored as a specific combination of place cell activities in the hippocampus.
May-Britt and Edvard Moser find the coordinates
May-Britt and Edvard Moser were mapping the connections to the hippocampus in rats moving in a room when they discovered an astonishing pattern of activity in a nearby part of the brain called the entorhinal cortex. Here, certain cells were activated when the rat passed multiple locations arranged in a hexagonal grid (Figure 2). Each of these cells was activated in a unique spatial pattern and collectively these “grid cells” constitute a coordinate system that allows for spatial navigation. Together with other cells of the entorhinal cortex that recognize the direction of the head and the border of the room, they form circuits with the place cells in the hippocampus. This circuitry constitutes a comprehensive positioning system, an inner GPS, in the brain (Figure 3). Continue reading
How to Tour the World’s Greatest Science Labs
Around the globe, physics and astronomy labs—some on mountaintops, others underground—welcome visitors to tour the premises
By Alastair Bland at smithsonian.com
They may be at work pursuing the greatest mysteries of the physical world—yet the men and women who operate the world’s most prestigious physics and astronomy laboratories aren’t necessarily too busy to host guests. Throughout the world, physics and astronomy labs—many of them shimmering like stars in the wake of tremendous discoveries and achievements, some on mountaintops, others underground—welcome visitors to tour the premises, see the equipment, look through the telescopes and ponder just why they almost always make you wear a hardhat.
CERN. It’s the little things in life that really matter to the researchers at CERN, or the European Organization for Nuclear Research. This facility—located near Geneva, Switzerland—has gained superstardom over the last year, after announcing the discovery of what had been a holy grail of physics for decades—sometimes called the “God particle.” First predicted by physicist Peter Higgs in 1964, the then-theoretical particle, which pops from a field that is believed to give other particles their mass—became known as the Higgs boson before more recently assuming its grandiose nickname. CERN’s $10 billion atom smasher, called the Large Hadron Collider, had been at work for several years in its subterranean home in the Alps, beneath the French-Swiss border, colliding protons at high speeds before rendering what seemed to be evidence for the God particle in 2012. After a year of analyzing data, CERN researchers officially announced in March that it was all but certain: They’d captured a handful of real, honest-to-God Higgs bosons (visible only via a peak on a graph of data). Should you be in the charming Swiss countryside this summer, consider taking a guided tour of this most distinguished of the world’s great physics laboratories.
Did you know? CERN’s researchers helped develop the World Wide Web as a way to share data among scientists.
Gran Sasso National Laboratory. Bundle up, say goodbye to the Italian sun and take a tour of the austere bowels of one of the largest underground laboratories in the world. The Gran Sasso National Laboratory welcomes visitors, who get to see some of the world’s finest physicists in action as they work on a variety of experiments. The laboratory is located thousands of feet below ground, beside a freeway tunnel within Gran Sasso e Monti della Laga National Park, and as wolves, deer and foxes in the wild country above chase and gobble each other up in their timeless ways, scientists in the Gran Sasso lab are busy pursuing the puzzles of neutrino physics, supernovas and dark matter. As part of an ongoing joint project, the Gran Sasso lab receives neutrino beams fired from the CERN lab, some 500 miles away. By observing a pattern of oscillations in such beams, protected from interfering particles by rock and water, scientists have been able to prove that neutrinos do have mass. (Still wearing that hardhat, I hope?)
W. M. Keck Observatory. Some of the largest telescopes on Earth stand on the summit of Mauna Kea, the 13,800-foot volcano on the Big Island of Hawaii. These instruments—about eight stories tall and weighing 300 tons each—have allowed researchers to pursue the most vexing of the universe’s questions: How do solar systems form? How fast is the universe expanding? What is its fate? Visitors age 16 and older can tour the site at a fee of $192. The tours last a marathon eight hours and include transportation, dinner, hot drinks and hooded parkas—which few tourists ever even think of packing along to Hawaii. WARNING: The high altitude of the site can pose pressure-related health hazards, and SCUBA divers should not visit the Keck Observatory shortly after any significant time spent underwater.
Stem Cell Reports
Click here to read the current volume
Aims and Scope
Poster «The Ebola Virus»
The Ebola virus and it’s close relative the Marburg virus are members of the Filoviridae family. These viruses are the causative agents of severe hemorrhagic fever, a disease with a fatality rate of up to 90% [12]. The Ebola virus infects mainly the capillary endothelium and several types of immune cells. The symptoms of Ebola infection include maculopapular rash, petechiae, purpura, ecchymoses, dehydration and hematomas [13].
Since Ebola was first described in 1976, there have been several epidemics of this disease. Hundreds of people have died because of Ebola infections, mainly in Zaire, Sudan, Congo and Uganda [14]. In addition, several fatalities have occurred because of accidents in laboratories working with the virus [15]. Currently, a number of scientists claim that terrorists may use Ebola as a biological weapon [14, 16].
In the 3D model presented in this study, Ebola-encoded structures are shown in maroon, and structures from human cells are shown in grey. The Ebola model is based on X-ray analysis, NMR spectroscopy, and general virology data published in the last two decades. Some protein structures were predicted using computational biology techniques, such as molecular modeling.
Harvard Stem Cell Institute (HSCI)
As the largest collaborative of its kind, the Harvard Stem Cell Institute is a unique scientific enterprise — a community of scientists and clinical experts in stem cell science seeking to bring new treatments to the clinic and new life to patients with a wide range of chronic illnesses.
To pursue the promise of stem cell and regenerative biology, in 2004, Harvard created a novel academic home for researchers and students, and a network of stem cell scientists extending from the University to its affiliated hospitals and the biomedical industry. Leveraging this unique environment, Harvard’s program has helped to change the paradigm for biomedical research and education by emphasizing cooperative teams and student participation in cutting-edge science.
The Harvard community consists of the largest concentration of biomedical researchers in the world, which allows us to advance stem cell biology and translational medicine in a way no other single entity can. Stem cell biologists across all the departments, schools, institutes, and affiliated hospitals of Harvard are able to collaborate on a daily basis with scientist-physicians, chemists, bioengineers, experts in business, law, and ethics, in order to develop tomorrow’s treatments and cures today.
LiveScience.com
- Has Earth’s Missing Heat Been Found?
- Zombies and Prosthetic Limbs? The Many Uses of 3D Scanners
- Michael Brown’s Autopsy: What It Can (and Can’t) Tell Us
- Image of the Day
- Cold, Dark and Alive! Life Discovered in Buried Antarctic Lake
- Body Odor and Brain Waves: 5 Cool New ID Technologies
- Get a Death Grip! Why Snakes Don’t Slip When Climbing Trees
- Ancient Toothless Pterosaurs Once Dominated the World’s Skies
- Men Who Make Virginity Pledges Struggle with Sex Once Married
Powers of Ten
Seen by 2,948,333
Powers of Ten takes us on an adventure in magnitudes. Starting at a picnic by the lakeside in Chicago, this famous film transports us to the outer edges of the universe. Every ten seconds we view the starting point from ten times farther out until our own galaxy is visible only a s a speck of light among many others. Returning to Earth with breathtaking speed, we move inward- into the hand of the sleeping picnicker- with ten times more magnification every ten seconds. Our journey ends inside a proton of a carbon atom within a DNA molecule in a white blood cell. POWERS OF TEN © 1977 EAMES OFFICE LLC (Available at www.eamesoffice.com)
Robin Williams’ Death: The Difference Between Depression & Normal Sadness
By Karen Rowan, Health Editor at LiveScience.com
Robin Williams was found dead this afternoon at his home near Tiburon, California, according to the Marin County Sheriff’s Office. The actor and comedian was 63.
Emergency personnel found Williams unconscious and not breathing at 12:00 p.m., local time; he was pronounced dead at 12:02 p.m., according to a news release from the Sheriff’s Office. Authorities are investigating the circumstances of death.
“At this time, the Sheriff’s Office Coroner Division suspects the death to be a suicide due to asphyxia, but a comprehensive investigation must be completed before a final determination is made,” the news release said.
A representative for Williams told Entertainment Weekly, “Robin Williams passed away this morning. He has been battling severe depression of late. This is a tragic and sudden loss. The family respectfully asks for their privacy as they grieve during this very difficult time.”
Major depression is one of the most common mental disorders in the United States, according to the National Institute of Mental Health. In 2012, an estimated 16 million U.S. adults had at least one major depressive episode, or bout of depressive symptoms, in the past year.
But despite how common the illness is, many people do not understand exactly what it means to have depression, and often think of it as being the same as sadness. [5 Myths About Suicide, Debunked]
“Depression is one of the most tragically misunderstood words in the English language,” writes Stephen Ilardi, an associate professor of clinical psychology at the University of Kansas, in a blog post on the Psychology Today website. “When people refer to depression in everyday conversation, they usually have something far less serious in mind,” than what the disorder actually entails. “In fact, the term typically serves as a synonym for mere sadness.”
Here are some facts about depression:
- Although major depression can strike people of any age, the median age at onset is 32.5, according to Washington University School of Medicine in St. Louis.
- Depression is more common in women than in men, according to Washington University.
- Men with depression are more likely than depressed women to abuse alcohol and other substances, according to Jill Goldstein, director of research at the Connors Center for Women’s Health and Gender Biology at Brigham and Women’s Hospital in Boston. Depressed men may also try to mask their sadness by turning to other outlets, such as watching TV, playing sports and working excessively, or engaging in risky behaviors, Goldsetein told Live Science in an interview earlier this year.
- Men’s symptoms of depression may be harder for other people to recognize, and the illness is missed more frequently in men, Goldstein said.
- Men with depression are more likely than women with the condition to commit suicide, Goldstein said. Men with depression may go longer without being diagnosed or treated, and so men may develop a more devastating mental health problem.
- Symptoms of depression extend far beyond feeling sad, and may include: loss of interest and pleasure in normal activities, irritability, agitation or restlessness, lower sex drive, decreased concentration, insomnia or excessive sleeping and chronic fatigue and lethargy, according to Mayo Clinic.