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A good violin depends not only on the expertise of the violin maker, but also on the quality of the wood that is used.

Swiss wood researcher

has succeeded in modifying the wood for a violin through treatment with special fungi

making it sound indistinguishably similar to a Stradivarius

discovered two species of fungi

which decay Norway spruce and sycamore – the two important kinds of wood used for violin making – to such an extent that their tonal quality is improved

Normally fungi reduce the density of the wood, but at the same time they unfortunately reduce the speed with which the sound waves travel through the wood

unique feature of these fungi is that they gradually degrade the cell walls, thus inducing a thinning of the walls

, a stiff scaffold structure remains via which the sound waves can still travel directly

the wood remains just as resistant to strain as before the fungal treatment

Before the wood is further processed to a violin, it is treated with ethylene oxide gas. "No fungus can survive that

mycowood (wood treated with wood decay fungi

on September 7, 2012 in

reported on his research and gave a preview of what his wood treatment method could mean, particularly for young violinists

In 2009 the violins were played in a blind, behind-the-curtain test versus a genuine Stradivarius from 1711

Both the jury of experts and the majority of the audience thought that the mycowood violin that Schwarze had treated with fungi for nine months was the actual Strad

Currently Professor Schwarze is working on an interdisciplinary project to develop a quality-controlled treatment for violin wood, with successful, reliable and reproducible results

cessful implementation of biotechnological methods for treating soundboard wood could in the future give young musicians the opportunity to play on a violin with the sound quality of an expensive – and for most musicians unaffordable – Stradivarius

Imagine going to the doctor for your aching knees

what if your doctor could actually listen to your body, monitoring the way your knees sound as they bend and flex

an instrument called a Surface Forces Apparatus (SFA), a device that measures the adhesion and friction forces between surfaces—in this case cartilage, the pad of tissue that covers the ends of bones at a joint.

degeneration of cartilage is the most common cause of osteoarthritis: The pads wear away, leaving bone grinding against bone

researchers found is that it isn't just any kind of friction that leads to the irreversible wear and tear on the material

currently believed that a high-friction force, or 'coefficient of friction,' is the primary factor in surface wear and damage

found is that this is not the case

The critical feature is not a high-friction force, but what is known as "stick-slip" friction, or, sometimes, "stiction."

Both are characterized by surfaces that initially stick together, and then accelerate away quickly once the static friction force is overcome

With stick-slip friction, the surfaces eventually pull slightly apart and slide across each other, stick again, and pull apart, causing jerky movements.

That's when things get damaged microscopically

Stick-slip is a common phenomenon. It is responsible for everything from computer hard drive crashes and automobile failures, to squeaking doors and music

same thing happens with a violin string

Even if you're pulling the bow steadily, it's moving in hundreds or thousands of little jerks per second, which determine the sound you hear

Each little jerk, no matter how submicroscopic, is an impact, and over time the accumulation of these impacts can deform surfaces, causing irreparable damage—first microscopically, then growing to macroscopic

it's not easy to tell the difference between types of friction at the microscopic level

Smooth-sliding joints might feel the same as those undergoing stiction, or the even more harmful stick-slip, especially in the early stages of arthritis

when measured with an ultra-sensitive and high-resolution instrument like the SFA, each type of friction revealed its own characteristic profile

Smooth-sliding joints yielded an almost smooth constant line (friction force or friction trace

with stiction showed up as a peak, as the "sticking" was being overcome, followed by a relatively smooth line

stick-slip shows the jagged saw-tooth profile of two surfaces repeatedly pulling apart, sticking, and pulling apart again

these measurements could be recorded by placing an acoustic or electric sensing device around joints, giving a signal similar to an EKG.

this could be a good way to measure and diagnose damage to the cartilage

to measure the progression, or even the early detection of symptoms related to arthritis

Early detection of conditions like arthritis has been a priority for many years

the functioning of joints is more complicated

scientists will continue their work by studying synovial fluid—the lubricating fluid between two cartilage surfaces in joints

plays a major role in whether or not the surfaces wear and tear, and the synergistic roles of the different molecules (proteins, lipids, and polymers

all involved in lubricating and preventing damage to our joints.

a number of directions to take, both fundamental and practical

it looks as if we need to focus our research on finding ways to prevent stick-slip motion, rather than lowering the friction force

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