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3-D Printers Make Custom Medical Implants

 

The team comprised of doctoral students and research faculty from Louisiana Tech’s biomedical engineering and nanosystems engineering programs collaborated to create filament extruders that can make medical-quality Read more →

3D printing filaments. Creating these filaments, which have specialized properties for drug delivery, is a new concept that can result in smart drug delivering medical implants or catheters.

“After identifying the usefulness of the 3D printers, we realized there was an opportunity for rapid prototyping using this fabrication method,” said Jeffery Weisman, a doctoral student in Louisiana Tech’s biomedical engineering program. “Through the addition of nanoparticles and/or other additives, this technology becomes much more viable using a common 3D printing material that is already biocompatible. The material can be loaded with antibiotics or other medicinal compounds, and the implant can be naturally broken down by the body over time.”

According to Weisman, personalized medicine and patient specific medication regiments is a current trend in healthcare. He says this new method of creating medically compatible 3D printing filaments will offer hospital pharmacists and physicians a novel way to deliver drugs and treat illness.

“One of the greatest benefits of this technology is that it can be done using any consumer printer and can be used anywhere in the world,” Weisman said.

Weisman, who works out of a lab directed by Dr. David K. Mills, professor of biological sciences and biomedical engineering, partnered with Connor Nicholson, a doctoral candidate in nanosystems engineering and member of a lab operated by Dr. Chester Wilson, associate professor of electrical and nanosystems engineering, to develop the technology in collaboration with Mills. The group also worked with Extrusionbot, LLC of Phoenix, Arizona, who provided important materials support throughout the development and testing process.

“We had been working on several applications of 3D printing,” said Mills. “Several students in my lab including Jeff and Connor, who was a guest researcher from Dr. Wilson’s lab, had been working with colleagues for some time. I sent an email to them and asked them the question, ‘Do you think it would be possible to print antibiotic beads using some kind of PMMA or other absorbable material?’”

From that point, the technology evolved and has become a highly innovative approach to overcoming many of the limitations encountered in current drug delivery systems. Most of today’s antibiotic implants, or “beads,” are made out of bone cements which have to be hand-mixed by a surgeon during a surgical procedure and contain toxic carcinogenic substances. These beads, which are actually a type of Plexiglas, do not break down in the body and require additional surgery for removal. Weisman and his team’s custom 3D print filaments can be made of bioplastics which can be resorbed by the body to avoid the need for additional surgery.

The nature of the 3D printing process developed at Louisiana Tech allows for the creation of partially hollow beads that provide for a greater surface area and increased drug delivery and control. Localized treatment with the 3D printed antibiotic beads also avoids large systemic drug dosages that are toxic and can cause damage to a patient’s liver and kidneys.

“Currently, embedding of additives in plastic requires industrial-scale facilities to ensure proper dispersion throughout the extruded plastic,” explains Mills. “Our method enables dispersion on a tabletop scale, allowing researchers to easily customize additives to the desired levels. There are not even any industrial processes for antibiotics or special drug delivery as injection molding currently focuses more on colorants and cosmetic properties.”

“It is truly novel and a worldwide first to be 3D printing custom devices with antibiotics and chemotherapeutics.”

The team said the environment at Louisiana Tech played a large role in this project making the progress it has, in a relatively short period of time. “The project has been able to advance to this point because of the support of and easy access to interdisciplinary facilities and outstanding faculty such as Drs. Mills, Wilson and [Dr. Mark] DeCoster,” said Weisman. “They and their labs have been crucial in taking cell culture and chemotherapeutic related aspects of this project to the next level”

“It is important to continue support of this research and to help bring Louisiana Tech to the forefront of rapid prototyping designs that will have impacts on a national scale.”

Everything you need to know about the Ebola virus

Where does Ebola come from?

Everything you need to know about the Ebola virus

The first known incidents of the Ebola virus were in 1976. There were two simultaneous outbreaks in Nzara in Sudan and Yambuku in Zaire (now the Democratic Republic of Congo). The name of the Ebola river near Yambuku was given to the new epidemic.

Outbreaks have mainly occured in remote villages in Central and West Africa, close to tropical rainforests.

In the current outbreak, which began in March 2014, more than 1,000 people have died in West Africa, mainly in Guinea, Sierra Leone and Liberia.

Ebola is described by Read more →

the World Health organisation (WHO) as “one of the most virulent viral diseases known to humankind.”

There are five distinct species of Ebola and the survival rate ranges from 25 to 90%.

There is no licensed vaccine for Ebola although several are currently being tested.

 

How is the Ebola virus transmitted?

 

  • Ebola is passed to humans through close contact with the blood or bodily fluids of infected animals. Fruit bats, monkeys and chimpanzees can all carry the virus.
  • Ebola then spreads through human-to-human transmission, again from contact with blood or bodily fluids.
  • Burial ceremonies where mourners touch the body of the dead person can also spread the disease.
  • The incubation period (the time from infection to the onset of symptoms) is between two to 21 days.
  • People remain infectious as long as their blood and secretions contain the virus.

 

What are the symptoms?

 

Initial symptoms include the sudden onset of a high fever, muscle pain, general weakness, headache and sore throat.

Further symptoms include vomiting, diarrhoea, rashes, damage to the kidney and liver function.

In some cases symptoms can include both internal and external bleeding.

There is no known cure or vaccine for Ebola.

 

How can the virus be prevented?

 

  • Routinely cleaning and disinfecting farms to inactivate the virus.
  • Animals should be handled with gloves and protective clothing. Meat should be thoroughly cooked before eating.
  • If an outbreak is suspected in animals, the premises should be quarantined and infected animals culled.
  • Avoiding physical contact with people infected with Ebola and protective clothing must be worn.
  • Washing hands after visiting patients in hospital, or after taking care of those infected at home.
  • Inform the authorities when a community is affected so containment measures can be taken.
  • Ebola victims should be buried quickly and safely, with no direct contact with the corpse.

 

What is being done to treat it?

 

Several vaccines are being tested, but none have been approved for clinical use.

One of the untested drugs, Zmapp, has been used on two American missionaries who are said to be improving. It was also given to a Spanish priest who later died. Its effectiveness is unknown but the WHO has ruled its use ethical in the circumstances.

Severely ill patients require intensive supportive care. Patients are frequently dehydrated and require oral rehydration with solutions containing electrolytes or intravenous fluids.

Stocks of Zmapp, which was developed by an American pharmaceutical company, have been sent to West Africa. The company says it has given the treatment free of charge.

Canada has also sent around 1000 doses of an experimental drug developed by government laboratories. It has previously shown promising results in animals but has never been tested on humans.

 

 

 

Source: euronews

 

 

 

Why global warming is taking a break

Global warming is currently taking a break: whereas global temperatures rose drastically into the late 1990s, the global average temperature has risen only slightly since 1998 — surprising, considering scientific climate models predicted considerable warming due to rising greenhouse gas emissions. Climate sceptics used this apparent contradiction to question climate change per se — or at least the harm potential caused by Read more →

greenhouse gases — as well as the validity of the climate models. Meanwhile, the majority of climate researchers continued to emphasise that the short-term ‘warming hiatus’ could largely be explained on the basis of current scientific understanding and did not contradict longer term warming.

Researchers have been looking into the possible causes of the warming hiatus over the past few years. For the first time, Reto Knutti, Professor of Climate Physics at ETH Zurich, has systematically examined all current hypotheses together with a colleague. In a study published in the latest issue of the journal Nature Geoscience, the researchers conclude that two important factors are equally responsible for the hiatus.

El Niño warmed Earth

One of the important reasons is natural climate fluctuations, of which the weather phenomena El Niño and La Niña in the Pacific are the most important and well known. “1998 was a strong El Niño year, which is why it was so warm that year,” says Knutti. In contrast, the counter-phenomenon La Niña has made the past few years cooler than they would otherwise have been.

Although climate models generally take such fluctuations into account, it is impossible to predict the year in which these phenomena will emerge, says the climate physicist. To clarify, he uses the stock market as an analogy: “When pension funds invest the pension capital in shares, they expect to generate a profit in the long term.” At the same time, they are aware that their investments are exposed to price fluctuations and that performance can also be negative in the short term. However, what finance specialists and climate scientists and their models are not able to predict is when exactly a short-term economic downturn or a La Niña year will occur.

Longer solar cycles

According to the study, the second important reason for the warming hiatus is that solar irradiance has been weaker than predicted in the past few years. This is because the identified fluctuations in the intensity of solar irradiance are unusual at present: whereas the so-called sunspot cycles each lasted eleven years in the past, for unknown reasons the last period of weak solar irradiance lasted 13 years. Furthermore, several volcanic eruptions, such as Eyjafjallajökull in Iceland in 2010, have increased the concentration of floating particles (aerosol) in the atmosphere, which has further weakened the solar irradiance arriving at Earth’s surface.

The scientists drew their conclusions from corrective calculations of climate models. In all climate simulations, they looked for periods in which the El Niño/La Niña patterns corresponded to the measured data from the years 1997 to 2012. With a combination of over 20 periods found, they were able to arrive at a realistic estimate of the influence of El Niño and La Niña. They also retroactively applied in the model calculations the actual measured values for solar activity and aerosol concentration in Earth’s atmosphere. Model calculations corrected in this way match the measured temperature data much more closely.

Incomplete measured data

The discrepancy between the climate models and measured data over the past 16 years cannot solely be attributed to the fact that these models predict too  much warming, says Knutti. The interpretation of the official measured data should also be critically scrutinised. According to Knutti, measured data is likely to be too low, since the global average temperature is only estimated using values obtained from weather stations on the ground, and these do not exist everywhere on Earth. From satellite data, for example, scientists know that the Arctic region in particular has become warmer over the past years, but because there are no weather stations in that area, there are measurements that show strong upward fluctuations. As a result, the specified average temperature is too low.

Last year, British and Canadian researchers proposed an alternative temperature curve with higher values, in which they incorporated estimated temperatures from satellite data for regions with no weather stations. If the model data is corrected downwards, as suggested by the ETH researchers, and the measurement data is corrected upwards, as suggested by the British and Canadian researchers, then the model and actual observations are very similar.

Warming to recommence

Despite the warming hiatus, Knutti is convinced there is no reason to doubt either the existing calculations for the climate activity of greenhouse gases or the latest climate models. “Short-term climate fluctuations can easily be explained. They do not alter the fact that the climate will become considerably warmer in the long term as a result of greenhouse gas emissions,” says Knutti. He believes that global warming will recommence as soon as solar activity, aerosol concentrations in the atmosphere and weather phenomena such as El Niño naturally start returning to the values of previous decades.

Student develops solar-powered lens that purifies polluted water

 

water-lens

Named a water lens, this device has been designed for communities in developing countries to very Read more →

easily and quickly treat their water before using it. The device is made from inexpensive and commonly found materials, such as wood and plastic sheeting, and can heat a litre of water to between 54 and 65 degrees Celsius (130 and 150 degrees Fahrenheit) in a little over an hour. During this time, it will destroy 99.9 percent of bacteria and pathogens in the water.

“The water lens could have a huge impact in developing countries,” said developer Deshawn Henry, a University at Buffalo engineering student, in a press release. “Millions of people die every year from diseases and pathogens found in unclean water, and they can’t help it because that’s all they have. Either they drink it or they die.”

The lens is constructed by pulling a plastic sheet covered with water over a wooden frame. The frame holds a small container of water underneath the plastic lens, which has been lined up with a focal point created by a concentrated ray of sunlight. Because the Sun moves across the sky throughout the day, the water container needs to be manually shifted to ensure it remains in line with the focal point.

In developing the water lens, Henry had to figure out how altering the thickness of the plastic sheet and the volume of water over the sheet would affect its efficiency. He found that adding more water to the lens made it more efficient, because larger areas of water transmitted more energy from sunlight. But larger areas of water required thicker sheets of plastic, which consumed more energy from from light, therefore lowering the lens’ efficiency.

Henry managed to find the happy medium between the two, reporting that, “a 0.7-millimetre sheet could efficiently heat the container while supporting eight litres of water, but any more and the sheet could potentially break”.

The next step for the water lens is for Henry to develop an even bigger version. According to Phys.org, a family of five would need a lens at least three times the size of the current water lens, which has been designed to heat one litre of water at a time.

Don’t panic – an asteroid is not set to wipe out the Earth in 2880

earth-near

 

Originating at the Telegraph and replicated by various other news outlets last week, the story that asteroid 1950 DA is set to wipe out life on Earth in 2880 was inspired by recent research that examined how rapidly this asteroid rotates.

Conducted by Read more →

researchers at the University of Tennessee in the US, the results of the study did little to suggest that the well-known asteroid’s chances of hitting the Earth had in any way increased, but the team did find something rather remarkable about the way it’s been spinning as it makes its way around its orbital path. According to Phil Plait at Slate:

“The asteroid spins so quickly that it should fly apart! You might think of asteroids as solid, monolithic chunks of rock, but we know that some are “rubble piles”, collections of smaller rocks held together presumably by their own gravity. They probably started out solid, but repeated collisions over the eons have riddled them with cracks, so they are more like gigantic bags of shattered rock.”

Discovered in 1950, Asteroid 1950 DA is a rubble pile, and it’s rotating so quickly that a ‘day’ on this asteroid lasts about two Earth hours. An object that’s spinning so fast – especially an object that’s made up of a bunch of smaller objects – should fly apart, but for some reason 1950 DA remains intact, and scientists aren’t entirely sure why.

This new research, published in Nature, seeks to explain the phenomenon, suggesting that a concept known as the van der Waals force could be in play. The van der Waals force describes the effects of an electrostatic charge that occurs between molecules, and it’s often used to explain how geckos stick themselves so effortlessly to walls and ceilings. Where asteroid 1950 DA is concerned, the tiny force of momentum that’s created by the infrared photons it emits when it’s warm could, over many years, affect how it rotates, and where its orbital path leads.

Which ties into what makes 1950 DA interesting to news outlets who love a good asteroid scare. In 2002, asteroid 1950 DA had the highest ‘Palermo rating’ – a scale used by astronomers to rate an object’s chance of impact – of all known near-Earth objects, and since then it’s become somewhat of a poster-child for alarmist space news. Near-Earth objects, or NEOs, are registered as such if their orbits take them within a relatively close distance to Earth, and by “relatively”, we mean on the cosmic scale.

To put this in perspective: “Looking over the next few decades, a typical pass [for 1950 DA] is tens of millions of kilometres away, with some as close as five million kilometres – which is still more than 10 times farther away than the Moon!” says Plait at Slate. “Still, that’s in our neighbourhood, which is one of the reasons this asteroid is studied so well. It gets close enough that we can get a decent look at it when it passes.”

But could it impact the Earth? Plait says yes, but some force would need to alter its orbital path in order for this to happen, and that’s an extremely difficult, if not impossible, thing to predict.But as Plait points out, we do have measurements of its orbital behaviour stretching back to 1950, which means we have a better idea of the asteroid’s future movements than we do for any other known asteroid.

Last year, scientists mapped out their predictions for 1950 DA based on these measurements, and after accounting for all the small effects that could change its orbital path over many years, they’ve come up with their figure. ”They found that the probability of an impact in 2880 is about 2.48 x 10-4, which is about 1 in 4000,”  says Plait. “That’s really small.”

Looks like we’re probably going to be okay after all.

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