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Subliminal Perception: Just How Fast Is The Brain? - Neuroskeptic. Why Are Women Stripy? In the awesome YouTube video below by Veritasium, Derek Muller explains why women are stripy.

Why Are Women Stripy?

I won’t give too much away, but I’ll briefly introduce the topic of epigenetics for those who don’t know much about it. Epigenetics refers to changes gene activity that occurs without alterations to the DNA sequence itself. Epigenetic modifications can switch genes on or off and determine which particular proteins are produced in different cells of the body. Epigenetics is essential since all of the cells in your body possess the same DNA sequence, but different types of cell require different proteins to be produced. It is these changes in gene expression that are therefore responsible for the different types of cell found in the body, or cell specialization. There are a few different ways to silence genes, for example DNA methylation. Breakthrough therapy allows four paraplegic men to voluntarily move their legs. Four young men who have been paralyzed for years achieved groundbreaking progress—moving their legs—as a result of epidural electrical stimulation of the spinal cord, an international team of life scientists reports today in the medical journal Brain.

Breakthrough therapy allows four paraplegic men to voluntarily move their legs

The study, conducted by researchers from the University of Louisville, UCLA and the Pavlov Institute of Physiology, was funded in part by the Christopher and Dana Reeve Foundation and the National Institutes of Health. All four participants were classified as suffering from chronic, motor complete spinal cord injuries and were unable to move their lower extremities prior to the implantation of an epidural stimulator. The stimulator delivers a continuous electrical current to the participants' lower spinal cords, mimicking signals the brain normally transmits to initiate movement.

Ultra-Sharp Images of Cells, Made Using Fluorescent DNA - Wired Science. This ultrasharp image uses a new method to simultaneously resolve microtubules (green), mitochondria (purple), Golgi apparatus (red), and peroxisomes (yellow) from a single human cell.

Ultra-Sharp Images of Cells, Made Using Fluorescent DNA - Wired Science

The scale bar is 5 microns. Image: Maier Avendano/Wyss Institute. Sea otter, dolphin, and penguin behavior: Your favorite animals are jerks. Pandoravirus: Missing link discovered between viruses and cells. With the discovery of Mimivirus ten years ago and, more recently, Megavirus chilensis[1], researchers thought they had reached the farthest corners of the viral world in terms of size and genetic complexity.

Pandoravirus: Missing link discovered between viruses and cells

With a diameter in the region of a micrometer and a genome incorporating more than 1,100 genes, these giant viruses, which infect amoebas of the Acanthamoeba genus, had already largely encroached on areas previously thought to be the exclusive domain of bacteria. For the sake of comparison, common viruses such as the influenza or AIDS viruses only contain around ten genes each. In the article published in Science, the researchers announced they had discovered two new giant viruses: Biologists Home in on Tiger Stripes and Turing Patterns [Slide Show] From Simons Science News (find original story here).

Biologists Home in on Tiger Stripes and Turing Patterns [Slide Show]

In 1952, Alan Turing, a British mathematician best known for his work on code-breaking and artificial intelligence, was convicted of engaging in homosexual acts and sentenced to chemical castration. Amid that personal drama, he still found the time to publish a visionary paper on the mathematics of regularly repeating patterns in nature, which could be applied to the stripes on tigers and zebra fish, the spots on leopards and the spacing in rows of alligator teeth, to name a few.

Now, more than 60 years later, biologists are uncovering evidence of the patterning mechanisms that Turing proposed in his paper, prompting a resurgence of interest in them, with the potential to shed light on such developmental questions as how genes ultimately make a hand. Human hearing beats sound’s uncertainty limit, makes MP3s sound worse. Modern audio compression algorithms rely on observations about auditory perceptions.

Human hearing beats sound’s uncertainty limit, makes MP3s sound worse

For instance, we know that a low-frequency tone can render a higher tone inaudible. Neverending DNA and Immortal Worms. Extrasensory Perception - Plants. Cell circuits remember their history: Engineers design new synthetic biology circuits that combine memory and logic. MIT engineers have created genetic circuits in bacterial cells that not only perform logic functions, but also remember the results, which are encoded in the cell's DNA and passed on for dozens of generations.

Cell circuits remember their history: Engineers design new synthetic biology circuits that combine memory and logic

The circuits, described in the Feb. 10 online edition of Nature Biotechnology, could be used as long-term environmental sensors, efficient controls for biomanufacturing, or to program stem cells to differentiate into other cell types. "Almost all of the previous work in synthetic biology that we're aware of has either focused on logic components or on memory modules that just encode memory.

We think complex computation will involve combining both logic and memory, and that's why we built this particular framework to do so," says Timothy Lu, an MIT assistant professor of electrical engineering and computer science and biological engineering and senior author of the Nature Biotechnology paper. Cilia. This Is What a Virus Infecting a Cell Looks Like. XVIVO.

Origin of life: Hypothesis traces first protocells back to emergence of cell membrane bioenergetics. Birds Hold Funerals for Their Dead. Funerals by definition are ceremonies honoring a dead person, but researchers have just observed what appears to be the avian version of a funeral.

Birds Hold Funerals for Their Dead

NEWS: Modern Birds Are Really Baby Dinosaurs Teresa Iglesias and colleagues studied the western scrub jay and discovered that when one bird dies, the others do not just ignore the body. Multiple jays often fly down to gather around the deceased. Future - Science & Environment - Will we ever… photosynthesise like plants? The discovery that some animals have found ways to feed off the Sun’s energy has led to the intriguing idea that humans could one day create solar-powered nourishment.

Future - Science & Environment - Will we ever… photosynthesise like plants?

Humans have to grow, hunt, and gather food, but many living things aren’t so constrained. Plants, algae and many species of bacteria can make their own sustenance through the process of photosynthesis. They harness sunlight to drive the chemical reactions in their bodies that produce sugars. Could humans ever do something similar? Jawless fish purges 20 percent of its genome from most cells. Not all of our cells have the same genome.

Jawless fish purges 20 percent of its genome from most cells

A few cell types, mostly immune cells, undergo a programmed deletion of small sections of DNA, and so don't end up with the genome that started in the fertilized egg that ultimately produced them. But most cells in the body end up with the same genome, which is one of the reasons it's possible to convert many of them back to stem cells. That said, most specialized adult tissues don't need all the genes they inherit. In fact, activating the unneeded genes—turning on liver enzymes in a muscle cell, for example—would generally be harmful. How your body beats the heat. Culture Connoisseur Badge Culture Connoisseurs consistently offer thought-provoking, timely comments on the arts, lifestyle and entertainment.

More about badges | Request a badge. Scientists find missing evolutionary link using tiny fungus crystal. The crystal structure of a molecule from a primitive fungus has served as a time machine to show researchers more about the evolution of life from the simple to the complex. By studying the three-dimensional version of the fungus protein bound to an RNA molecule, scientists from Purdue University and the University of Texas at Austin have been able to visualize how life progressed from an early self-replicating molecule that also performed chemical reactions to one in which proteins assumed some of the work. "Now we can see how RNA progressed to share functions with proteins," said Alan Lambowitz, director of the University of Texas Institute for Cellular and Molecular Biology. "This was a critical missing step. " The crystal structure of an RNA molecule bound to a protein was used by Purdue and University of Texas at Austin researchers to study a stage of evolution.

Japanese scientists use particle accelerator to create salt-resistant rice. Ant Death Spiral. The Single Theory That Could Explain Emergence, Organisation And The Origin of Life. Evolutionary conundrum of the day: Single-celled organisms kill themselves. Single-celled organisms, such as this green algae, kill themselves. Life-like cells are made of metal - life - 14 September 2011. Paul Snelgrove: A census of the ocean. Neuroscience News, Videos, Reviews and Gossip - io9. A mitosis mystery solved: How chromosomes align perfectly in a dividing cell. To solve a mystery, sometimes a great detective need only study the clues in front of him. Like Agatha Christie's Hercule Poirot and Arthur Conan Doyle's Sherlock Holmes, Tomomi Kiyomitsu used his keen powers of observation to solve a puzzle that had mystified researchers for years: in a cell undergoing mitotic cell division, what internal signals cause its chromosomes to align on a center axis?

Mike deGruy: Hooked by an octopus. Craig Venter is on the verge of creating synthetic life. Evolution of complexity recreated using 'molecular time travel' Much of what living cells do is carried out by "molecular machines" -- physical complexes of specialized proteins working together to carry out some biological function. Drew Berry: Animations of unseeable biology. Shot of young stem cells makes rapidly aging mice live much longer and healthier, researchers report. Mice bred to age too quickly seemed to have sipped from the fountain of youth after scientists at the University of Pittsburgh School of Medicine injected them with stem cell-like progenitor cells derived from the muscle of young, healthy animals.

Instead of becoming infirm and dying early as untreated mice did, animals that got the stem/progenitor cells improved their health and lived two to three times longer than expected, according to findings published in the Jan. 3 edition of Nature Communications. Inside the mind of the octopus. Annie Murphy Paul: What we learn before we're born. 29+ Evidences for Macroevolution: Part 1. Martin Hanczyc: The line between life and not-life. 01.12.2009 - Mice without key enzyme eat without becoming obese, new study finds. By Sarah Yang, Media Relations | 12 January 2009. Christoph Adami: Finding life we can't imagine.

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Zombie Virus Drives Caterpillars To An Explosive Death.