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It's Official: Voyager 1 Is Now In Interstellar Space - 0 views

  • NASA says the most distant human made object — the Voyager 1 spacecraft — is in interstellar space
  • It actually made the transition about a year ago
  • there is a bit of an argument on the semantics of whether Voyager 1 is still inside or outside of our Solar System
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  • it is not farther out than the Oort Cloud
  • it will take 300 more years reach the Oort cloud and the spacecraft is closer to our Sun than any other star
  • the plasma environment Voyager 1 now travels through has definitely changed from what comes from our Sun to the plasma that is present in the space between stars.
  • debate
  • There’s also been a
  • between the latest various science papers and their authors
  • Scientists thought that when the spacecraft had crossed over into interstellar space, the magnetic field direction would change
  • that didn’t happen
  • scientists determined they needed to look at the properties of the plasma instead
  • The Sun’s heliosphere is filled with ionized plasma from the Sun
  • Outside that bubble, the plasma comes from the explosions of other stars millions of years ago
  • The main tell-tail difference is the interstellar plasma is denser.
  • the real instrument that was designed to make the measurements on the plasma quit working in the 1980’s
  • Instead they used the plasma wave instrument, located on the 10-meter long antennas on Voyager 1 and
  • from the Sun
  • a massive Coronal Mass Ejection
  • The antennas have radio receivers at the ends – “like the rabbit ears on old television sets
  • The CME erupted from the Sun in March 2012, and eventually arrived at Voyager 1′s location 13 months later, in April 2013
  • Because of the CME, the plasma around the spacecraft began to vibrate like a violin string
  • The pitch of the oscillations helped scientists determine the density of the plasma
  • the particular oscillations meant the spacecraft was bathed in plasma more than 40 times denser than what they had encountered in the outer layer of the heliosphere
  • The plasma wave science team reviewed its data and found an earlier, fainter set of oscillations in October and November 2012 from other CMEs
  • extrapolation of measured plasma densities from both events, the team determined Voyager 1 first entered interstellar space in August 2012
  • certainly in a new region at the edge of the solar system where things are changing rapidly
  • not yet able to say that Voyager 1 has entered interstellar space
  • the data are changing in ways that the team didn’t expect
  • after further review, the Voyager team generally accepts the August 2012 date as the date of interstellar arrival
  • The charged particle and plasma changes were what would have been expected during a crossing of the heliopause
  • expect the fields and particles science instruments on Voyager will continue to send back data through at least 2020
  • , it was first questioned in August of 2012, with more speculation in December 2012, then in March of 2013
  • Then about a month ago
  • Voyager 2, launched before Voyager 1, is the longest continuously operated spacecraft
  • emitted signals are currently very dim, at about 23 watts — the power of a refrigerator light bulb
  • Voyager mission controllers still talk to or receive data from Voyager 1 and Voyager 2 every day
  • planetary alignment that only happens every 176 years enabled the two spacecraft to join together to reach all the outer planets in a 12 year time period
  • By the time the signals get to Earth, they are a fraction of a billion-billionth of a watt
  • Data from Voyager 1′s instruments are transmitted to Earth typically at 160 bits per second
  • signal from Voyager 1 takes about 17 hours to travel to Earth.
  • After the data are transmitted to JPL and processed by the science teams, Voyager data are made publicly available
  • Scientists do not know when Voyager 1 will reach the undisturbed part of interstellar space where there is no influence from our Sun
  • They also are not certain when Voyager 2 is expected to cross into interstellar space, but they believe it is not very far behind.
  • While Voyager 1 will keep going, we will not always be able to communicate with it, as we do now
  • In 2025 all instruments will be turned off, and the science team will be able to operate the spacecraft for about 10 years after that to just get engineering data
  • In the year 40,272 AD, Voyager 1 will come within 1.7 light years of an obscure star in the constellation Ursa Minor
Mars Base

Desert Farming Experiment Yields First Results | Science/AAAS | News - 0 views

  • A project to “green” desert areas with an innovative mix of technologies—producing food, biofuel, clean water, energy, and salt
  • A pilot plant built by the Sahara Forest Project (SFP) produced 75 kilograms of vegetables per square meter in three crops annually, comparable to commercial farms in Europe, while consuming only sunlight and seawate
  • The heart of the SFP concept is a specially designed greenhouse. At one end, salt water is trickled over a gridlike curtain so that the prevailing wind blows the resulting cool, moist air over the plants inside
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  • This cooling effect allowed the
  • facility to grow three crops per year, even in the scorching summer
  • At the other end of the greenhouse is a network of pipes with cold seawater running through them
  • Some of the moisture in the air condenses on the pipes and is collected, providing a source of fresh water
  • One of the surprising side effects of such a seawater greenhouse, seen during early experiments, is that cool moist air leaking out of it encourages other plants to grow spontaneously outside
  • Qatar plant took advantage of that effect to grow crops around the greenhouse, including barley and salad rocket (arugula), as well as useful desert plants
  • The pilot plant accentuated this exterior cooling with more “evaporative hedges” that reduced air temperatures by up to 10°C.
  • The third key element of the SFP facility is a concentrated solar power plant
  • This uses mirrors in the shape of a parabolic trough to heat a fluid flowing through a pipe at its focus. The heated fluid then boils water, and the steam drives a turbine to generate power
  • the plant has electricity to run its control systems and pumps and can use any excess to desalinate water for irrigating the plants
  • The fact that this small greenhouse produced such good yields,
  • suggests that a commercial plant—with possibly four crops a year—could do even better
Mars Base

SpaceX Aborts Thanksgiving Rocket Launch Due to Engine Trouble | Space.com - 0 views

  • SpaceX's Falcon 9 rocket fired its engines and was moments away from liftoff from Cape Canaveral
  • but the commercial booster aborted the launch after computers detected the engines were too slow building up thrust.
  • Engineers raced to understand and resolve the problem, but they could not get comfortable enough to attempt the launch again
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  • Officials had not announced a new target launch date
  • SpaceX was targeting liftoff of the 22-story rocket at 5:39 p.m. EST (2239 GMT) Thursday, aiming to achieve the first Thanksgiving Day launch from Florida's Space Coast since 1959
  • The launch was pushed back to Thursday after multiple technical problems thwarted an initial launch attempt Monday
  • The rocket's mission is to place the SES 8 television broadcasting satellite into orbit
  • e highest altitude ever achieved by a SpaceX launch.
  • the flight is critical to SpaceX's future in the commercial launch market, in which it competes against stalwart launch vehicles from Europe and Russia to haul large telecommunications satellites into orbit.
  • The Falcon 9 pressurized its propellant tanks, switched to internal power and ignited its nine Merlin 1D first stage engines a few seconds before the appointed launch time
  • the Falcon 9's computer-controlled countdown sequencer recognized a problem and called off the launch
  • As engineers continued to study the problem, SpaceX elected to restart the countdown to preserve a chance to launch Thursday
  • Ultimately, however, SpaceX said they could not get comfortable with the issue in time and ordered another hold with less than a minute left in the day's second countdown.
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Update on Space Station Cooling System | NASA - 0 views

  • Dec. 11, 2013
  • the pump module on one of the space station’s two external cooling loops automatically shut down when it reached pre-set temperature limits
  • These loops circulate ammonia outside the station to keep both internal and external equipment cool
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  • suspect a flow control valve actually inside the pump module itself might not be functioning correctly
  • At no time was the crew or the station itself in any danger
  • ground teams did work to move certain electrical systems over to the second loop
  • Some non-critical systems have been powered down inside the Harmony node, the Kibo laboratory and the Columbus laboratory
Mars Base

How Our Brain Balances Old and New Skills - 0 views

  • To learn new motor skills, the brain must be plastic: able to rapidly change the strengths of connections between neurons, forming new patterns that accomplish a particular task
  • if the brain were too plastic, previously learned skills would be lost too easily.
  • A new computational model developed by MIT neuroscientists explains how the brain maintains the balance between plasticity and stability
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  • and how it can learn very similar tasks without interference between them.
  • The key
  • is that neurons are constantly changing their connections with other neurons
  • not all of the changes are functionally relevant - they simply allow the brain to explore many possible ways to execute a certain skill, such as a new tennis stroke
  • As the brain learns a new motor skill, neurons form circuits that can produce the desired output
  • according to this theory
  • As the brain explores different solutions, neurons can become specialized for specific tasks
  • brain is always trying to find the configurations that balance everything so you can do two tasks, or three tasks, or however many you're learning
  • Perfection is usually not achieved on the first try, so feedback from each effort helps the brain to find better solutions
  • complications arise when the brain is trying to learn many different skills at once
  • Because the same distributed network controls related motor tasks, new modifications to existing patterns can interfere with previously learned skills.
  • particularly tricky when you're learning very similar things
  • such as two different tennis strokes
  • computer chip,
  • instructions for each task would be stored in a different location on the chip.
  • the brain is not organized like a computer chip. Instead, it is massively parallel and highly connected - each neuron connects to, on average, about 10,000 other neurons
  • That connectivity offers an advantage, however, because it allows the brain to test out so many possible solutions to achieve combinations of tasks
  • neurons
  • have a very low signal to noise ratio, meaning that they receive about as much useless information as useful input from their neighbors
  • The constant changes in these connections,
  • researchers call hyperplasticity
  • balanced by another inherent trait of
  • Most models of neural activity don't include noise, but the MIT team says noise is a critical element of the brain's learning ability
  • This model helps to explain how the brain can learn new things without unlearning previously acquired skills
  • the paper shows is that, counterintuitively, if you have neural networks and they have a high level of random noise, that actually helps instead of hindering the stability problem
  • Without noise, the brain's hyperplasticity would overwrite existing memories too easily
  • low plasticity would not allow any new skills to be learned, because the tiny changes in connectivity would be drowned out by all of the inherent noise
  • The constantly changing connections explain why skills can be forgotten unless they are practiced often, especially if they overlap with other routinely performed tasks
  • skills such as riding a bicycle, which is not very similar to other common skills, are retained more easily
  • Once you've learned something, if it doesn't overlap or intersect with other skills, you will forget it but so slowly that it's essentially permanent
  • researchers are now investigating whether this type of model could also explain how the brain forms memories of events, as well as motor skills
Mars Base

Large Hadron Collider team announces beginning of restart - 0 views

  • scientists working at CERN's Large Hadron Collider (LHC) facility has reported
  • that the process of restarting the massive experimental mechanism has begun
  • though it won't finish until sometime next year
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  • will have to be restarted in pieces to ensure that each is operating properly before the next can be brought online
  • the facility is in the process of an upgrade, which has been in the planning stages for several years and will include upgrades to several pieces and parts of the facility that support the LHC as well as the main accelerator itself
  • The team recognized that the facility had begun to suffer from diminishing returns
  • many parts could be improved due to the development of new technology and improvements on old ways of doing things.
  • the team has successfully restarted the part they call the source—the piece of equipment responsible for stripping electrons off of hydrogen atoms for use in producing protons.
  • Next up the team plans to fire up Linac2, an accelerator whose job it is to give protons their initial push
  • After that a booster will be started that will be used to push the protons even faster
  • For the LHC to be used in its proper context, it must receive protons that are already moving exceedingly fast.
  • Team members have made much of the complete upgrade to the control system
  • that integrates all of the systems and which of course will be central to a successful reboot.
  • In addition to swapping out parts for new and improved technology, technicians will also be replacing worn cables or other minor but necessary components
  • If all goes well, the LHC should be ready and back in business sometime early next year.
Mars Base

April 22 - Today in Science History - Scientists born on April 22nd, died, and events - 0 views

  • Surgery book
  • In 1575, printing of Ambroise Paré's book Oeuvres Complètes (Complete Works) was finished, but its publication was opposed by establishment physicians. His previous texts on surgery had popularized a new way to treat gunshot wounds without cauterisation, reintroduced the ligature in amputation, and improved midwifery techniques. These many writings were gathered together in this one new volume, which spread his teachings throughout the world. It remained in print for a century and ran to thirteen editions. He wrote in French instead of Latin with practical, common sense so that many barber-surgeons, who (like Paré) were unable to interpret Latin, had access to medical knowledge otherwise unavailable from Latin texts
Mars Base

April 16 - Today in Science History - Scientists born on April 16th, died, and events - 0 views

  •  First woman to fly across English Channel
  • In 1912, American aviator Harriet Quimby became the first female pilot to fly across the English Channel. She left England in a 50-hp monoplane lent to her by Louis Blériot. She headed for France in a plane she had never flown before and a compass she had just learned how to use. Despite poor visibility and fog, Quimby landed 59 minutes later near Hardelot, France. Upon landing, she was greeted by the local residents, but the Titanic sinking just days earlier, limited reporting of Quimby's achievement in the world press. She died the same year, on 1 Jul 1912, when she lost control of her plane at a flying exhibition near Quincy, Mass. She was the first American woman to become a licensed pilot, but her career as a pilot lasted a mere 11 months.
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June 25 - Today in Science History - Scientists born on June 25th, died, and events - 0 views

  • Space station Mir accident
  • In 1997, the space-station Mir suffered a near-fatal mishap when a Progress ferry being docked via remote control by Russian cosmonaut Vasily Tsibliyev accidentally rammed into the Spektr science module, putting a hole in the pressure vessel and damaging its solar arrays beyond use. To salvage the station, which consisted of a core, a connecting node, and five science modules, crew members severed electrical and data connections between Spektr and the rest of the station and then sealed off the module. They saved the station but lost about half of their electrical power
Mars Base

An Autonomous, Self-Steering Robo-Cane, And Other Co-Robots to Come | Popular Science - 0 views

  • National Robotics Initiative, a federal program that aims to push the development of co-robots, or bots that work alongside—and occasionally inside—humans
  • NRI is a panoply of loosely-related ideas, few of which are photogenic
  • But this research is worth a closer look
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  • the bots that could become part of our lives, in our own lifetimes, won’t look like Boston Dynamics’ Atlas, or NASA’s (and GM’s) Robonaut 2. Chances are, they’ll look a lot more like a walking stick, with a bunch of stuff bolted onto it.
  • a navigation-aid,
  • the robotic cane being developed by the University of Arkansas at Little Rock acts as a kind of seeing-eye walking stick
  • It maps the user’s path with a vision and 3D camera, and picks out stairways, low overhangs, and other features of interest to the visually-impaired
  • the bot will be able to verbally warn or guide the operator, speaking through a Bluetooth earpiece (and possibly through tactile feedback), it will also be able to perform limited steering maneuvers
  • . “In navaid mode, the device's roller tip is activated, and may drive the cane and point it towards the desired direction of travel
  • The six-degree-of-freedom roller isn’t driving the operator, but making suggestions, and can be toggled on and off by switching between navaid and white cane modes
  • robots designed by companies like iRobot can already drive themselves around indoors with a minimum of collisions
  • problems of obstacle detection and avoidance are far from licked
  • The margin of failure for a robot cane has to be vanishingly small, and that level of accuracy could also benefit systems that aren’t attached to humans
  • the co-robotic cane was co-funded for a three-year period by the National Institute of Biomedical Imaging and Bioengineering (NIBIB) and the National Eye Institute (NEI), both of which are part of NIH
  • One of the new projects funded by NSF is an effort to make robots that can better read the emotional needs of Parkinson’s sufferers, specifically those whose faces have been significantly paralyzed
  • In order to serve as mediators between victims of “facial masking” and their caregivers
  • the project aims to “develop a robotic architecture endowed with moral emotional control mechanisms, abstract moral reasoning, and a theory of mind that allow corobots to be sensitive to human affective and ethical demands
  • whether it will be an existing system, or a new one
  • is unclear
  • one of the project’s collaborators is
  • the famous (or infamous, depending on your perspective) roboticist who proposed the use of so-called “ethical governors” for autonomous military robots
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Researchers identify brain cells responsible for keeping us awake - 0 views

  • Bright light makes it easier to stay awake
  • Very bright light not only arouses us but is known to have antidepressant effects.
  • Bright light makes it easier to stay awake.
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  • dark rooms can make us sleepy.
  • researchers at UCLA have identified the group of neurons that mediates whether light arouses us — or not
  • the cells necessary for a light-induced arousal response are located in the hypothalamus
  • an area at the base of the brain responsible for, among other things, control of the autonomic nervous system, body temperature, hunger, thirst, fatigue — and sleep.
  • the activity of hypocretin neurons in their WT littermates was maximized when working for positive rewards during the light phase, but the cells were not activated when performing the same tasks in the dark phase.
  • These cells release a neurotransmitter called hypocretin
  • This current finding explains prior work in humans that found that narcoleptics lack the arousing response to light, unlike other equally sleepy individuals
  • researchers examined the behavioral capabilities of mice that had their hypocretin genetically "knocked-out" (KO mice) and compared them with the activities of normal, wild-type mice (WT) that still had their hypocretin neurons
  • they found that the KO mice were only deficient at working for positive rewards during the light phase
  • During the dark phase, however, these mice learned at the same rate as their WT littermates and were completely unimpaired in working for the same rewards
  • This same UCLA research group earlier determined that the loss of hypocretin was responsible for narcolepsy and the sleepiness associated with Parkinson's disease
  • findings suggest that administering hypocretin and boosting the function of hypocretin cells will increase the light-induced arousal response
  • Conversely, blocking their function by administering hypocretin receptor blockers will reduce this response and thereby induce sleep
  • implications for treating sleep disorders as well as depression
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Dragon V2: SpaceX's Next Generation Manned Spacecraft | SpaceX - 0 views

  • The vehicle holds seats for 7 passengers, and includes an Environmental Control and Life Support System (ECLSS) that provides a comfortable environment for crewmembers
  • Dragon V2’s robust thermal protection system is capable of lunar missions, in addition to flights to and from Earth orbit
Mars Base

International Cometary Explorer - Wikipedia, the free encyclopedia - 0 views

  • Original mission: International Sun/Earth Explorer 3 (ISEE-3)
  • to investigate solar-terrestrial relationships at the outermost boundaries of the Earth's magnetosphere
  • to examine in detail the structure of the solar wind near the Earth and the shock wave that forms the interface between the solar wind and Earth's magnetosphere
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  • investigate motions of and mechanisms operating in the plasma sheets
  • continue the investigation of cosmic rays and solar flare emissions in the interplanetary region near 1 AU
  • Second mission: International Cometary Explorer
  • On June 10, 1982, after completing its original mission, ISEE-3 was repurposed. It was renamed the International Cometary Explorer (ICE)
  • The primary scientific objective of ICE was to study the interaction between the solar wind and a cometary atmosphere
  • a series of lunar orbits over the next 15 months. Its last and closest pass over the Moon, on December 22, 1983, was a mere 119.4 km above the Moon's surface. By the beginning of 1984, ICE was in heliocentric orbit
  • Giacobini-Zinner encounter
  • on a trajectory intercepting that of Comet Giacobini-Zinner.
  • On 11 September 1985, the craft passed through the plasma tail of Comet Giacobini-Zinner
  • ICE carried no cameras. It instead carried instruments for measurements of energetic particles, waves, plasmas, and fields
  • Halley encounter
  • transited between the Sun and Comet Halley in late March 1986, when other spacecraft
  • were in the vicinity of Comet Halley
  • ICE flew through the tail
  • Heliospheric mission
  • mission was approved by NASA in 1991
  • consisting of investigations of coronal mass ejections in coordination with ground-based observations
  • End of mission
  • On May 5, 1997, NASA ended the ICE mission, and ordered the probe shut down, with only a carrier signal left operating
  • Further contact
  • In 1999, NASA made brief contact with ICE to verify its carrier signal. On September 18, 2008
  • NASA, with the help of KinetX, located ICE using the Deep Space Network after discovering that it had not been powered off after the 1999 contact
  • status check revealed that all but one of its 13 experiments were still functioning, and it still has enough propellant
  • Reboot effort
  • A team webpage said, "We intend to contact the ISEE-3 (International Sun-Earth Explorer) spacecraft, command it to fire its engine and enter an orbit near Earth, and then resume its original mission...If we are successful we intend to facilitate the sharing and interpretation of all of the new data ISEE-3 sends back via crowd sourcing."
  • Sometime after NASA's interest in the ICE waned
  • A team of engineers, programmers, and scientists
  • realized that the spacecraft might be steered to pass close to another comet
  • began to study the feasibility and challenges involved
  • On May 15, 2014, the project reached its crowdfunding goal
  • which will cover the costs of writing the software to communicate with the probe, searching through the NASA archives for the information needed to control the spacecraft, and buying time on the dish antennas
  • The project then set a 'stretch' goal of $150,000
  • The project members are working on deadline: if they get the spacecraft to change its orbit by late May or early June 2014, it can use the Moon's gravity to get back into a useful halo orbit.
  • Earlier in 2014, officials with the Goddard Space Flight Center had said that the Deep Space Network equipment necessary to transmit signals to the spacecraft had been decommissioned in 1999, and that replacing it was not economically feasible
  • oject members obtained the needed hardware (power amplifier, modulator/demodulator[12]), and installed it on the 305-meter Arecibo dish antenna on May 19, 2014
  • Although NASA is not funding the project, it made advisors available and gave approval to try to establish contact
  • On May 21, 2014, NASA announced that it had signed a Non-Reimbursable Space Act Agreement with the ISEE-3 Reboot Project
  • "This is the first time NASA has worked such an agreement for use of a spacecraft the agency is no longer using or ever planned to use again," officials said
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April 3 - Today in Science History - Scientists born on April 3rd, died, and events - 0 views

  • First cell phone call
  • In 1973, the first portable phone call was placed by inventor Martin Cooper. The phone was 10 inches in height, 3 inches deep and an inch-and-a-half wide and weighed 30-oz. Since then, cell phones have shrunk to a mere palm-size weighing 4-oz, and are used by a billion people around the world. Cooper's first ''shoebox'' phone replaced a car phone of the time that weighed more than 30 pounds and cost thousands of dollars. A car phone owner had to drill a hole in his car to install the antenna and most of the phone sat in the trunk. A control unit with a handset was placed inside the car
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Reversal of type 1 diabetes in mice may eventually help humans - 0 views

  • Investigators at the University of Cincinnati (UC) have found a therapy that reverses new onset Type 1 diabetes in mouse models and may advance efforts in combating the disease among humans.
  • Type 1 diabetes is usually diagnosed in children and young adults and affects about 5 percent of all people with diabetes
  • . In Type 1 diabetes, the body does not produce sufficient insulin, which is central to glucose metabolism: without insulin, blood glucose rises
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  • There is no cure for Type 1 diabetes though it can be controlled with insulin therapy
  • by using an antibody to stimulate a specific molecule in the innate immune system we can reverse—with a high rate of success—new onset diabetes in mice that have already developed the symptoms of diabetes
  • The cause of this reversal is a preservation of the endocrine pancreatic beta cells that produce insulin
  • These cells are preserved from the autoimmune attack which is the hallmark of Type 1 diabetes
  • The key to reversing Type 1 diabetes in mice,
  • is catching the disease at its onset, which is typically within a very short time window
  • The time frame would be longer in humans, but it is still a relatively short time from new onset to end-stage Type 1 diabetes
  • Ridgway says this approach differs from most in combating Type 1 diabetes because his team's therapies in mice do not directly interact with T-cells
  • treatment of autoimmunity has often been directed at suppressing an over-zealous adaptive immune response by eliminating auto-reactive T-cells
  • In Type 1 diabetes, autoimmunity causes the body's T-cells to attack its insulin-producing beta cells.
  • targeting a different part of the immune system
  • There are two arms of the immune system.
  • respond to many different antigens
  • The innate system tends to have a stereotypical response. We are targeting a receptor that is found mostly on the innate immune cells, such as dendritic cells.
  • Additional study will be required, but the therapy may hold promise because one agonistic anti-TLR4 agent is already FDA approved and others are under development
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